Human ancestor reproduction after chromosome fusion

Question: I read somewhere that human chromosome 2 is the result of 2 primate chromosomes fusing together somewhere along our evolutionary journey. This is why we have 23 chromosomes while other primates have 24. My question is this: for the first ancestor whose chromosomes fused to have 23 chromosomes instead of 24, how did he reproduce? Don't offspring receive half of their genetic makeup from each parent, so if one parent has 23 chromosomes and the other has 24, how would that work? I know that there have been animals with different chromosome counts being bred together, but the offspring typically have issues and are sterile, so even if the difference in chromosome count was not a problem, wouldn't the offspring between an organism with 23 chromosomes and one with 24 be infertile, thus leading to the end of animals with 23 chromosomes? Would there have to be two organisms of different genders experiencing the same chromosome fusion at the same time in order to avoid this problem? I'm just a bit confused as to how this would work exactly.
Comment: Related: [Polymorphism in number of chromosomes?](https://biology.stackexchange.com/questions/59826/polymorphism-in-number-of-chromosomes)
Answer: Strangely enough we actually do have an answer for that.
There are a several examples of individuals who are born with two chromosomes fused together in all their cells.
We even have a few examples where these fused chromosome is in a diploid state, ie all instances of that chromosome are fused in the individual. Such individuals come from families in small isolated villages that are very inbred.
Chromosome number does not prevent fertility but it does reduce it in heterozygous state as it is now harder to get correct chromosome distribution during meiosis and thus fewer functional gametes are made. However in terms of function, as all genes are present in a somatic cell in the correct number, function is usually normal and the individual is alive.
If the population is inbred, it is possible to get an egg and a sperm that carry the same fused chromosome to meet. In which case you get a diploid individual with fused chromosomes. Fertility is now restored. And in an inbred population, a homozygote individual for the fused chromosome can meet another similar individual, and have offspring who are fully fertile.
AS you can imagine, over time there is a selection pressure for the population to separate. The homozygous state (be it fused or unfused chromosome) is more fertile that the heterozygous state.
So to put it short, chromosome fusion does not kill a cell. All gene are still present. However in the heterozygous state, where both fused and unfused chromosomes are present, fertility is dramatically reduced BUT is none zero. Fertility is restored in a homozygous state when an individual is diploid for either fused or unfused chromosomes. In small isolated populations, inbreeding allows for the emergence of diploid individuals which can reproduce with each other
http://genetics.thetech.org/original_news/news124
Answer:
My question is this: for the first ancestor whose chromosomes fused to
  have 23 chromosomes instead of 24, how did he reproduce?

He or she reproduced the same way people today with balanced Robertsonian translactions reproduce.  During meiosis I, the separated chromosomes line up with the fused one, so the resultant cell gets either the replicated fused chromosome, or the replicated separate chromosomes.  Then meiosis proceeds as usual, with half the gametes having the fused chromosome, and half having the two separate chromsomes.  The fused chromosome has just about all the information the two separate ones have, so the gametes with the fused chromosome can go one to make a organism with all the required genetic information.


Choices before birth

Question: Before we are born, do we pick who our parents, guides, and rebbaim in life will be?
Answer: Before a person is born, Hashem decides his or her basic life circumstances: whether they will be poor or rich, strong or weak, etc. The only thing that's not decided, and is up to the person themselves, is whether they will be righteous or not (Niddah 16b).
"Who one's parents are," then, clearly falls into the category of things that Hashem determines in advance.
"Who one's guides, etc., are" may be more of a gray area. Suppose that Hashem decides that one person should be born into an Ashkenazic family in America, and another into a Sephardic family in Israel. It is indeed more likely that each of them will have different teachers and halachic authorities, but it's not carved in stone; each of them may consciously choose a different path in Jewish life than what they were born into (or even, G-d forbid, abandon Judaism altogether).
Comment: To add to Alex: the Gemara says (Pesachim 54b) that we don't know what kind of job will be best for us; we have to figure that out on our own.  Similarly, Rabbi Aryeh Kaplan in his book on marriage writes that the "bashert" (before you're born, a Heavenly voice says so-and-so should be your wife)  is the most-likely person for you, assuming he and she take the most likely choices in life.  But either of you can use free will and choose to drastically change your life, at which point you get a new "bashert."
Comment: @Shalom: With regards to Bashert, see my answer here for a listing of the different opinions about a bashert: http://judaism.stackexchange.com/a/8125/603
Answer: No. In fact we fight with Hashem not to send us at all.
Comment: "Fight" is a strong term, maybe, but Avos 4:22 (4:29 in some editions) does say that "against your will you are born," and Bartenura there explains that the neshamah is in fact taken forcibly from On High and placed into the womb.
Comment: What is your source?
Comment: Yes, but that does not tell us whether or not we have choice where we end up when we get here other than that we are forced to come.

Choices before birth


In any major key, what Roman Numerals indicate the major, minor, and diminished chords?

Question: I was wondering what the Roman Numerals are. I though it was I,III, V, for major key but that was not it.
Answer: Major keys use the one major (I) the four major (IV) and the five major (V).  When forming chords (triads) using the notes available in a diatonic major key (7 possible notes) the one, four and five chords end up being major, the two, three, and six chords minor and the seventh diminished.
It is common to use an "uppercase" Roman Numeral to represent major chords (I, IV, V) and lower case to indicate minor (ii, iii, vi) and the little ° for diminished (vii°).  But I have seen it represented differently so that is not a hard and fast rule about how to denote major versus minor.  It is a hard and fast rule that the I, IV and V chords in any diatonic major key will be major and the only major chords that can be formed from the notes in that key.
Here is a chart showing the chords for all the major keys.  The T and S at the top of this chart are for Tone (T) and Semitone (S) and shows that in a major key the intervals between notes in a diatonic major scale are - tone, tone, semitone, tone, tone, tone semitone. Also referred to as whole, whole, half, etc.  (steps).
Answer: The Roman Numerals that indicate major, minor, and diminished are the same in any kind of key and all keys will have seven possible Roman Numerals from 1 to 7 one for each scale degree. The specifics for the quality of the chords are as follows:

A major chord will always be represented by an upper case Roman Numeral I.E. : I, II, III, IV, V, VI, VII are all major.
A minor chord will always be represented by an lower case Roman Numeral I.E. : i, ii, iii, iv, v, vi, vii are all minor.
A diminished chord will always be represented by an lower case Roman Numeral and a circle. I.E. : i°, ii°, iii°, iv°, v°, vi°, vii° are all diminished.
An augmented chord will always be represented by an upper case Roman Numeral I.E. : I+, II+, III+, IV+, V+, VI+, VII+ are all augmented.

So let's look at the key of C major and the chords natrually built from it.  Because we naturally get the chord C, Dm, Em, F, G, Am, and Bdim, we end up with the Roman Numerals I, ii, iii, IV, V, vi, and vii°.
For more information about this, you can view the lessons about Roman Numerals on musictheoy.net which go a little more in depth on this topic, but covers the same points.
Answer: People usually use

capital letters for major chords, like I,IV and V
lower case for minor chords like ii,iii,vi
lower case with diminished symbol for diminished chords, like viiø (for half diminished ones) and vii° for diminished ones.

But, I have seen people symbolizing the minor chords with capital letters as well.
Answer: Shevliaskovic already explained the roman numerals in a key, but let me explain the "1-3-5" you mentioned in your post, because this is a different concept.
1-3-5 are the note intervals used to create a major chord from the major scale.
For example, take the C major scale:
C-D-E-F-G-A-B-(C)
1-2-3-4-5-6-7-(1)

If you take the notes labeled 1-3-5 from the C major scale you get C-E-G, which is a C major chord.
This process is also called "stacking 3rds" because the notes are a 3rd apart. You can apply this process to each note in the major scale to build different the chords from the scale.
Move to the next number and take the notes labeled 2-4-6 you get D-F-A which is a D minor chord.
If you continue this process for all the notes, you get:
1-3-5 = C-E-G = C major chord
2-4-6 = D-F-A = D minor chord
3-5-7 = E-G-B = E minor chord
4-6-1 = F-A-C = F major chord (note the wrap around back to "1" here)
5-7-2 = G-B-D = G major chord
6-1-3 = A-C-E = A minor chord
7-2-4 = B-D-F = B diminished chord

Now, if you look at the pattern of chords created here, you get:
C major  D minor  E minor  F major  G major  A minor  B diminished

Notice the order of the major, minor, and diminished chords.
Maj min min Maj Maj min dim

Now apply the roman numeral convention that Shevliaskovic mentioned to this pattern and you get:
I ii iii IV V vi vii°

We've come full circle right back to the roman numeral pattern. :) So while the "1-3-5" note intervals and the "I IV V" roman numerals are different concepts they are also closely related.
Answer: The simple and straightforward answer is that there are seven triad chords built on the major scale. They are:
I ii iii IV V vi vii°
The chords numbered one, four, and five are major chords.
The chords numbered two, three and six are minor chords.
The chord numbered seven is a diminished chord.


How to do a good remote presentation?

Question: Due to COVID-19, I'm working from home, and I'm going to give a presentation from home. I wonder if some of good practices when giving presentation directly are still good? For example: do not put too many words in the slides => but now the audiences only have the slides to stare at, should I put more words?
Comment: One big difference with in-person presentations is that it is harder for you to judge whether the audience have understood you, because you can not see their faces and reaction, and even if you can the reactions are often delayed a bit. So one piece of advice is to ask regularly if there are any questions and if everything is clear, especially after explaining a concept that is important for understanding the rest of the presentation.
Comment: Practice with your technology to make sure you have the bugs worked out (e.g., your microphone sounds good, you know how to do things without fumbling, etc.)
Answer: Differences between a real in-person and a remote presentation are quite many, but the main key points of keeping an audience engaged remain the same. Assuming the audience can access the slides somewhere before or after the presentation, I would suggest to have pictorial representations of main concepts - use schematic diagrams and small bullet point sentences to assist them. Play around with bold fonts and highlight colours for texts, but not too much of any of these. There are many other good practices for giving a scientific and technical presentation, do perform a google search and find your preferred ones.
For a remote session, it is best to choose a platform where you can share your screen and keeping your video on, which actually adds a real feel to the presentation for the audience. It is good to have a plain background and silent environment as much as possible. If you choose a virtual background, make sure the software platform has had enough practice with it so that it can recognize between you and the background without patches of your face disappearing in the background. Structure your words more like a conversation and less like a monologue because even though the audience might be the best in this field, it is easy to zone out in such a session, so it is best to put in elements that attract attention and makes your talk easy to follow. Also, remember to number your slides/equations, etc so that they are easy to refer to.
Also, keep track of the time, if there is a chair or convener, probably they will give warnings, otherwise time yourself and don't rush or be overly slow, try to keep a steady tempo. A neutral tone is also a strong requirement for remote sessions because if your audience is spread across the planet, you don't want to come across as either a rude person or a bore.
I remember the speakers from remote sessions whose talks were natural and didn't seem too rehearsed and plastic. In the end, the content matters the most, but it is always pleasant to see it presented in an easier way - just like in a good paper.
Answer: No, I'm pretty sure that more words to stare (squint) at aren't going to be a big winner. If you can't switch back and forth between yourself and your material in a seamless way, then send them the materials prior to the presentation and refer to them as you go. Number them, perhaps to make reference easy.
But some sort of screen splitting software would be better, perhaps.
And assure that there is room/time for questions and an effective way to answer them.
And attend to what is seen in the background as you speak and make sure that you don't get interruptions from people/pets as you go.
Answer: May not be relevant for your situation, but I had added audio to my ppt presentations for building excel models using the Solver.
The students can work on the example in parallel, pause it as needed and, perhaps, mute me as needed :)
Feedback was good, as my students were in all the world's time zones so one single presentation was not going to cut it.

How to do a good remote presentation?


Why does my WIFI turn off randomly?

Question: I am using a government ZTE Qlink phone and the WIFI randomly turns itself off. I have too many contacts to perform a factory reset! I need help figuring it out!
Comment: Does it lose connection? Or the adapter actually turns off?
Answer: Practically all mobile phones are using the Google Contacts app to manage your contacts. They create a backup of your contacts to the Google, and continuously synchronizing with it. This is why you can see the same contacts on all your Android devices (if you have multiple).
If not this is the case on your phone, you need only to install the Google Contacts app.
If you don't want to share your contacts with the Google, there are also many third-party apps to save them to other cloud services, or to your own machine. You can find them quickly with Google searches :-)
Having your contacts saved with an app, your contact list will survive a factory reset. Note, there is a high chance, that it won't fix your problem. In my experience, such sudden wifi disconnections root probably in the bad hardware/driver, or in some overloading of your device by the recently hugely grown apps. If you have no better option, it surely worths a try.
Answer: Which phone are you using? Go to Settings -> About Phone and check for system updates. If an update is available, do it right away.
If the problem still persists, then you should try to reset your phone.
If you are worried about losing your contacts, then you don't need to worry. On an Android device, your contacts are already been synced with google service. You can even check your contacts on the https://contacts.google.com .
Many other free contact backup apps are also available on the Internet. So you can backup your contacts/sms/call_logs and everything else to external card and then restore them any time.

Why does my WIFI turn off randomly?


1099-INT shows '0' even though I received some interest

Question: Throughout the year I see little additions to my checking account for interest.  These are pretty small.  When I received my 1099-INT, all values were $0.00.  Is this a mistake, or did I just receive to little interest to be mentioned?
Comment: Did you receive less than $10 in interest? Less than $1?
Answer: If you earned interest from an institution/account then you will have to put it on the appropriate tax form or worksheet.  If the amount is small < $10 the bank/institution does not have to send you a 1099-Int but you still have to report it.
My credit union sends me a 1099-INT for each sub-account, even if that account doesn't reach that $10 limit, becasue the total is > $10. This means that they can send you one if the amount is < $10.
I am surprised that a 1099-INT was issued with an interest earned of $0.00. In light of the fact that you earned some small amount of interest, that means that their computer made a mistake. I would contact them. Maybe everybody is getting one that says zero. Maybe only you.
You should look at the monthly statements or log into the banks website and calculate the interest yourself. Sometimes they have a copy of the 1099-INT on line, sometimes they have a place which lists the amount of interest earned during the year.
Answer: In the Creative Solutions tax preparation software interest totals less than $5 at least used to be rounded down to zero and not even entered on the form. Between $5 and $10 rounded up to $10. I asked the CPAs, one of which had worked in product support for the company that produced Creative Solutions and I was told amounts that small were considered immaterial.
It's true that doesn't explain for sure your situation. Only your bank can tell for sure. But it's possible similar reasoning was used. I had a bank account with positive but close to zero interest and I didn't even get a 1099 for at least one year.
Comment: The IRS website linked here doesn't say anything about about a limit to interest being taxable or not, only a limit ($10) on whether it's required to be reported via a 1099-INT form.  https://www.irs.gov/taxtopics/tc403
Comment: The IRS requires all interest income to be reported (even if it's less than $10).  Also, the question being asked isn't whether to report this, but whether there is an error on the form.
Comment: Nearly all dollar amounts entered on any IRS form get rounded to the nearest $1.00, never $10.00.  That results in values less than $0.49 being non-reportable because they round to $0   It sounds like your memory has misplaced a decimal point, but otherwise the practice of rounding and ignoring interest that rounds to zero seems accurate.
Comment: Have a reference for that? The professional tax preparation software I have used ignored interest if it was less than ten dollars. I asked why and the response from the CPAs was the IRS didn't require amounts that small to be reported.
Comment: https://money.stackexchange.com/questions/75390/if-i-earned-less-than-10-in-interest-from-my-bank-account-do-i-need-to-report Most voted answer contains a cite that, yes, you do need to report interest income even if it's less than $10.


On proving the zero-one-law for first order logic

Question: I'm trying to understand the proof of the zero-one-law for first order logic as provided in (Ebbinghaus-Flum, 1995). It goes as follows:
Let $\tau$ be a relational signature. Let $r\in\mathbb{N}$, then $\Delta_{r+1}=\{\phi(v_1,\ldots,v_r,v_{r+1})\mid\phi\text{ has the form }R\bar x\text{, where }R\in\tau\text{ and where }v_{r+1}\text{ occurs in }\bar x\}$. For $\Phi\subseteq\Delta_{r+1}$, we say the extension axiom of $\Phi$ is:
$$\chi_\Phi=\forall v_1\ldots\forall v_r(\bigwedge_{1\leq i<j\leq r}v_i\neq v_j\rightarrow \exists v_{r+1}(\bigwedge_{1\leq i\leq r} v_i\neq v_{r+1}\wedge\bigwedge_{\phi\in\Phi}\phi\wedge\bigwedge_{\phi\in\Phi^c}\neg\phi)).$$
Now they prove
Lemma. Any extension axiom $\chi_{\Phi}$ holds in almost all finite structures, i.e. $l(\chi_\Phi)=\lim_{n\rightarrow\infty} \frac{L_n(\chi_\Phi)}{L_n(\tau)}=\lim_{n\rightarrow\infty}\frac{|\{\mathcal{A}\mid\mathcal A\models\chi_\Phi\wedge|A|=\{1,\ldots,n\}\}|}{|\{\mathcal A\mid|A|=\{1,\ldots,n\}\}|}=1$.
Proof. Given $\Phi$. For any tuple $a_1,\ldots,a_r$ of distinct elements in a structure $\mathcal A$ and any further object $a$ let $\delta$ be the probability that $a_1,\ldots,a_r,a$ satisfies $\Phi\cup\{\neg\phi\mid \phi\in\Phi^c\}$, when adding $a$ to $\mathcal A$ as a new element and randomly fixing the truth values of $R\bar b$ for any $R\in\tau$ and any sequence $\bar b$ in $A\cup\{a\}$ containing $a$. Clearly, if $c$ is the number of subsets of $\Delta_{r+1}$, $\delta=\frac1c$.
Until here I understand everything, but I don't understand the following derivation:
$$l_n(\neg\chi_\Phi)=l_n(\exists v_1\ldots\exists v_r(\ldots))\leq n^r(\tfrac{c-1}c)^{n-r}=n^r(1-\delta)^{n-r}.$$
I don't understand where the expression just after the inequality comes from, could someone explain this?
Update. I have found this article, in which they seem to prove a special case of the lemma above (see the proof of Lemma 0.3, (b) $\Rightarrow$ (c)). I'm still not fully able to make the generalisation to this case, could someone explain this?
Update II. By replacing $\frac1{2^2k}$ by $\frac1c$ in the above article, and thinking some more about the arguments in 1. and 2., I have been able to prove the lemma.
Update III. The replacement part in my last update wasn't really clear to me at that moment. I now have been able to fully prove it: Since we can choose our relations arbitrarily, for a relation $R\in\tau$ and a sequence of variables $\bar x$ of the right size, the probability of $R\bar x$ to hold equals $\tfrac12$.  So in total there are
$$\left(\dfrac12\right)^{\|\Delta_{r+1}\|}$$
sequences $v_1,\ldots,v_r,v_{r+1}$ in $\{1,\ldots,n\}$ that realise $\psi_\Phi$. If now $c$ is the amount of subsets of $\Delta_{r+1}$, then $c=2^{\|\Delta_{r+1}\|}$, and filling that in in my original proof, finally proves the lemma.
Answer: For the record, this lemma is proved in the lecture notes of Martin Otto on Finite Model Theory. I find it clear, short and self-contained.


What's the best way to bulk add or import categories?

Question: I'd like to import a long list of categories into ExpressionEngine and create new categories. Is there an easy way to do this, either via add-on, or some handy PHP code?
Answer: Use DataGrab -- http://devot-ee.com/add-ons/datagrab -- and import with a spreadsheet. If you have only one level for categories, it's super easy. If you have category levels or categories with same name, it's a little more complicated.
If you have levels, your spreadsheet (csv is best, IMO) can be created safely following these steps.

In EE, create the first top-level category. Note its cat_id.
Export the exp_categories table from your database (or create a spreadsheet with the exact same columns as that table).
Add a new row for a new category (best to keep it in order for sanity's sake). If the next category is a child of the first category your entered in EE, make sure to the parent category's id as this category's parent_id. Also, this category would have a cat_id one number higher than the first one you created.
Keep adding rows like that.

If you have categories with the same name, make sure to give them a unique cat_url_title.
Comment: I have datagrab, and as far as I can tell, you can only import categories as part of importing an entry. So, I guess I could import one entry that had all the categories I wanted to import, and then delete that entry... but even then, it seems pretty limited, and doesn't do parents, category groups, etc.
Comment: Or really you could skip datagrab and just import the updated spreadsheet directly to the database. Just export that table in .csv format first.
Comment: Fair enough -- a CSV import does seem like a pretty straightforward way, even if it does require a lot of DB knowledge to be able to use it :)


Cracked porcelain shower repair

Question: I live in Greece and have a very traditional house.I can't yet find a replacement porcelain shower tray the same dimensions. The original is cracked in several places but not leaking. I was thinking of covering it with a glue, a foundation and tiles or painting it with something that might stick??? Any ideas until I find a new one?
Porcelain on concrete maybe Anyhow, very thick and heavy dimensions: 70cm wide x 65 deep x inside height 12 and outside 18.
Comment: Hello, and welcome to Home Improvement. This is probably going to be opinion-based, but perhaps a picture or some more information would help. And, you should probably [take our tour](//diy.stackexchange.com/tour) so you'll know how best to participate here.
Comment: If it is cracked I suppose that it is porcelain (china) all the way through? Or is it porcelain on cast iron?
Comment: Thanks for the reply. I'm going to try to upload a photo. It's definitely not cast iron. Porcelain on concrete maybe Anyhow, very thick and heavy dimensions: 70cm wide x 65 deep x inside height 12 and outside 18.
Comment: If you can't find a replacement you might pull out the broken one and replace it with tiles.
Comment: Thanks, I was starting to think that way, but have recently found a smaller square shower tray (not as nice as the old one) haven't installed it yet, but hope the issue is closed.
Answer: Thanks for your input. No it doesn't leak "yet". I've tried the repair kit which I had to get posted here indirectly as there are restrictions on liquids sent through the post to Greece. It chipped off again and doesn't work on hairline cracks. I do airbnb renting, so not so nice for guests to see it bodged up. I would like to find another but it's about 25 years old, so a bit vintage. I've just made a wooden palette to stand on (suggestion of a friend), so hope guests don't peak underneath.
Answer:
Does it leak? If not, why fix it?
You can look for a porcelain repair kit. I swear I saw one years ago. Found some on  Amazon US. Surely you have an Amazon that can ship to you right?
Fill with white or clear silicone?
Would Amazon have a size you need?

No matter what fix you use, I believe you will still see a crack, but you will see a fixed crack.

Cracked porcelain shower repair


Submitting multiple websites to search engines

Question: There are many services that submit your website to multiple search engines. Are there any that allow you to easily submit multiple websites to multiple search engines?
Answer: I don't know of any, however, you will be putting different information each time you submit a site, so it's kind of a non-question. I mean, you have to type out all the information for each site so it makes no difference if you submit one at a time or all at once.
To be honest, you don't need to submit your site to any search engines; it's generally regarded as a waste of time. All you need is at least one link (not nofollow) to your site, and the search engines will find and index it just fine. You can also cross-link your sites if they are relevant to each other.
Comment: They will, but it could take a while for them to get to the link that takes them to your site.  If you need traffic fast, there's certainly nothing wrong with raising a flag to grab some attention.
Comment: @Kaji: If you have no links to your site there is no way you'll be "getting traffic fast". Submitting your site may get you indexed a little quicker but it probably won't make much difference.
Comment: I agree with DG. However, I just wanted to ensure my sites get listed in search engines before I get time to build links. (Want to avoid cross-linking my own sites for now).  There are simple ways/workarounds to do it and "paying" to submit to search engines is definitely a no-no.
Answer: Intuit's WebListings service will get you submitted to about a hundred different search engines.  It's primarily intended for businesses with a local presence, but it's also a way to get some great coverage with minimal effort.  Granted, it has to be purchased separately for each site you're using it to submit, so it might not be the most effective solution for someone with several sites, but it'll get the job done well for a single site.


Can a supernova make a new star?

Question: Today I was wondering with a friend about the birth of a star. So we know that stars are born from a nebula, but the residue of a dead star (like a supernova) is itself a nebula. So can a star be born from this nebula?
Comment: Where do you think most of the oxygen in your lungs came from? Or are you specifically asking whether 1 supernova remnant alone can give birth to new stars?
Comment: @WayfaringStranger Of course this can't happen. That's why I was trying to clarify what the question actually was. The simple answer is no. *A* supernova cannot "make a new star". But new born stars contain material produced by many supernovae. The question certainly isn't about triggering.
Comment: @RobJeffries for that to happen, you'd have to have sufficient material around to stop the explosive debris in it's tracks while it was still compact enough to self-gravitate. That, or a powerful interstellar magnetic bottle set up. Given supernova debris initial multi-thousand kps dispersion, that's just not likely.
Answer: This idea has been around for decades, so I'm not sure who first came up with it. Here's a reasonably sourced article on the involvement of supernova in solar system formation:Exploding Star May Have Sparked Formation of Our Solar System

The shock wave from an exploding star likely helped trigger the formation of our solar system, according to a new 3D computer model, researchers say.
  The solar system is thought to have coalesced from a giant rotating cloud of gas and dust known as the solar nebula about 4.6 billion years ago. For decades, scientists have suspected a star explosion called a supernova helped trigger our solar system's formation. In particular, the shock wave from the explosion is thought to have compressed parts of the nebula, causing these regions to collapse.
  According to this theory, the shock wave would have injected material from the exploding star into the solar nebula.

So yes, material from supernova can end up triggering the formation of new suns, and material from supernova do end up mixed in with the nebular material that makes the new stars.
Comment: In a universe where the star that went supernova is the *only* object, perhaps the ejected material would eventually slow, self gravitate, and form another, highly metallic star. Unless of course there's already a black hole or neutron star waiting to capture the material. There are other complications as well: Types of Supernova: https://en.wikipedia.org/wiki/Supernova#Type_I  In the context of a normal galaxy, supernova remnants are going to be dispersed by attraction to other gravitational bodies long before any secondary star has a chance to form from the original material.
Comment: So if an explosion will not find any new nebula, there could be a new star?

Can a supernova make a new star?


When creating a multisite, the sub-folders option is not available

Question: I have an existing Wordpress site, albeit just a skeletal one with a single page. I decided to enable multisites on it and dutifully followed the simple directions for doing so. However, when I reached the "Create A Network of Wordpress Sites" dialog under "Addresses of Sites in your Network", only the "Sub-domains" option was enabled; the "Sub-folders" option was disabled with an explanation something like 'You can't use sub-folders in an existing site.'  I found this peculiar because any site would have to exist before initiating the Multisite creation process, and so what made mine different? Any help would be appreciated.
Answer: From the Codex article Before You Create A Network:

You cannot choose Sub-directory Install (for a path-based network) if your existing WordPress installation has been set up for more than a month, due to issues with existing permalinks.

The easiest solution is to export your existing site (if it's got content you want to preserve), install a fresh WordPress Multisite installation, and then import your existing content into the new site.
Answer: Subfolder MultiSites are only allowed when you don't have any user-created content. That is because if you have pretty permalinks enabled, the subfolders could conflict with the slugs of existing Posts, Pages, or other content types. So if you chose, for example, /coolstuff/ as your first subsite but you already had a Post with a slug of /coolstuff/, WP would not know whether you wanted to show the subsite homepage or the parent site's Post.
If you just have a skeletal site with one Page, and you want a subfolder MultiSite, create a brand-new WP install and enable MultiSite. Then either copy and paste the Page, or you can export/import it.


Places offering samatha retreats / training

Question: I'm looking for a place to train in samatha. I want to master jhana and time is not an issue. I can also do volunteer work in exchange for training. Any recommendations?
Comment: Where are you located and how far are you willing to travel?
Answer: There is Pa-auk Forest Monastery in Myanmar (Burma). A good friend just spent a year there. He did a fair amount of research before settling for Myanmar and he also spent months in a temple in Thailand beforehand. According to him, various monks from Korea as well as Sri Lanka, etc. go to Myanmar thinking that qualified Dharma teachers are difficult to come by in their countries. It seems likes "The place to be." He also said that "Most practitioners require between three and eight years of dedicated effort to obtain the full set of jhanas."
I do not know much about Pa-Auk though. For instance, I do not know whether they train lay people as well.
Answer: If you are interested in coming to Ontario, Canada, this place - Tisarana Buddhist Monastery in Perth, Ontario, is the place for you. You can stay up to 3 months. You do not have to pay anything, but may have to do some volunteer work every other day. If you call them, it will be a person like you who will answer and give you all necessary details.  It is near Ottawa – the Capital City of Canada. I was there just two months ago. They have a very good library. Any bhikku will be of help to you while there. You can take a look into their FB Page too, if you like - as it will give you a better idea.
The monastery is a residence for Buddhist monks and those who wish to train as Buddhist monks. Presently there are 20 monks, and 4 'anagaarika's (trainee monks). It is a retreat for those  interested who may visit for varying periods of time.


Are there any options for connecting into main stack for venting branch below waterline?

Question: Are there any options for connecting into main stack for venting branch below waterline? Could I go up for a few feet with a with a wye join and then come back down? The reason for trying to come up with a solution to this is that I dont have access to the pipe above the waterline and the toilet connection and I'm trying to avoid running another pipe on the side of the house just to get venting for the basement bathroom.
Answer: The short answer is: No.
However, there are some other alternative solutions to avoid running another pipe outside the house you should consider:
Studor Vents
As N R stated, you can can use what are called 'air admittance valves' or 'Studor Vents' which are essentially just an air 'check valve' that allows the air to go into a pipe and is suppose to stop it from going back out of the pipe (so you don't smell swear gas).  The problem with these is that they don't always close unless there is a significant back flow of air, which is why they aren't always legal to use.

Chicago Vents
Alternatively, it seems unlikely  to me that you would have no other fixtures on the same floor that are already vented.  Consider running horizontally.  If your horizontal access to a vent would require you to go below run the vent piping below the wet line to you can use what is called a "Chicago Vent"
Answer: Unfortunately, wet venting in a waste stack is not allowed when a toilet is draining to the stack.  You have to vent from above the toilet.  Does your locality allow air admittance valves?  If you just need a vent for a laundry sink or something similar, you could go with that.


Is there a way to run Perl code from inside Excel and have it return a hash?

Question: I am trying to run some Perl code from Excel. If I try to pass something to the script using the shell command I am not able to return a value. I figure that if I am able to run the script in as a com module or something like that I might be able to get back a value, array or hash from the script. Does anyone know if this is possible? and if so How? Any help would be appreciated.
Answer: I am curious what is your desired result ... I mean do yo need to run a Perl script from Excel? Is it possible you could run it outside of Excel and get the same result?
If so, you could export the rows you need to perform whatever functionality the script is to do and then generate another spreadsheet using the following modules:
CPAN -> Spreadsheet::ParseExcel
CPAN -> Spreadsheet::WriteExcel
Answer: In the Perl script, write the desired return value to a temporary output file. In VB, wait until the Perl script process is complete, then open and parse the contents of that file. You could let VB choose the name of the temporary file and hand that name to the Perl script as a command line argument or an environment variable.


Getting up to date with the new features of c#

Question: I have just discovered that i need to start looking for a new job.  I have been working in basic features of c# 3.0 and i was never give the chances to play around with c# 4.0.
What is the best way to get up to date with all the new features in the framework?
Answer: The best way is the way that works for you. Are you the sort of person who learns how to do a task:

by trying to do the task
by reading about the task
by being tutored one-on-one by an expert in the task
by listening to lectures about the task
something else

?
We don't know how you learn, so we cannot answer the question. How do you learn best? It makes no sense at all to recommend a book to read if you're the sort of person who hates learning things from books but loves learning things by doing them.
Answer: all or any of following would help.

Read blogs
Read books
watch videos on msdn
Read SO discussions
Answer: Read the blogs, books, tutorials, watch videos, try sample applications and work at home. Once you've mastered the new features of .NET 4.0 you will have arguments to convince managers to give you the chance to migrate.
Answer: The MSDN latest news feed IMHO is a very good starting point to discover new features, the RSS is here:
http://go.microsoft.com/fwlink/?linkid=84795&clcid=409
Above this I check a lot of blogs, such as:
http://encosia.com/
http://weblogs.asp.net/scottgu/
Answer: Unlike the past couple of relases of C#, the new features this time are scattered all over. Pick some area that you think will really map into your career, like the parallel computing enhancements, or dynamic language support. If you've been doing a lot with generics, pick up the covariance and contravariance; they'll help a lot in some situations. I understand Expression support is improved as well; if you're a LINQ addict, you can probably do fun stuff with Expressions and expanding LINQ or writing your own query provider. If you work with COM, then look into the optional and named parameters.  Many possibilities.
Answer: If you have a gmail account, set up the associated Reader and add C# blog feeds. That is my wat of keeping up to date. Of course it would not to hurt to read the blogs as well.


if two arduinos are connected by I2C and one of them is using an ethernet shield, does that grant both of them access to the internet?

Question: i have two arduino mega and they send data to each other by an I2C connection. But one of those arduinos is connected to an ethernet shield which allows it to send data to a web server. Being both connected does that mean that they both can send or access the web server. Sorry if any ambiguity was found but I didnt find a better way to ask this question.
Answer: I2C does not automatically share resources between two connected devices. You would not be able to share an Internet connection from a Mega connected via I2C to another Mega which has an Ethernet shield.
However, you could write code for both Megas that implements a two-way communication in which the non-shield Mega sends requests or commands to the one with the Shield, and then passes that data back to the non-shield Mega.
However, you, as the coder, would be responsible for designing such a protocol and implementing it. It would be quite a task probably.
Comment: Thank you my friend, this couldn't be answered better.
Answer: It can but only if the one with the shield allows it (it acts like a router).
The only way for the arduino without the shield can communicate with the internet if it can send a message to the one with the shield and it will forward that message and return the replies back.


Unable to use in the same application a QWebPage twice

Question: I'm trying to create a little web server that loads, using webkit, an URL to extract some data from the web page (eg: title, images sizes...).
I'm using PyQt4 to access from python to webkit. For each request, I'm creating a QThread that:
- creates an QWebPage object,
- run an event loop
- when the loading of the webpage has finished (loadFinished signal), some code extracts data from the mainFrame of the QWebPage and kills the QThread
This works very well the first time, the web page is loaded, included all its resources (CSS, images).
The second time I ask the server to load an url, the web page is loaded, but none of its resources (no css, no images). So when I try to retrieve image sizes, all size are set to 0,0.
Here is some code snipset:

# The QThread responsible of loading the WebPage
class WebKitThread(QThread):
    def __init__(self, url):
        QThread.__init__(self)
        self.url = url
        self.start()
    def run(self):
        self.webkitParser = WebKitParser(self.url)
        self.exec_()

class WebKitParser(QWebPage):
    def __init__(self, url, parent=None):
        QWebPage.__init__(self, parent )
        self.loadFinished.connect(self._loadFinished)
        self.mainFrame().load(QUrl(url))

    def _loadFinished(self, result):
        self.computePageProperties()
        QThread.currentThread().exit()

    def computePageProperties(self):
        # Some custom code that reads title, image size...
        self.computedTitle=XXXXXXXX

The calling code (that respond to the HTTP request) is executing:

t = WebKitThread(url)
t.wait()
# do some stuff with properties of WebKitParser
print t.webkitParser.computedTitle
Answer: I've managed to fix the issue: creating the QWebPage in the GUI thread (the thread of QApplication event loop) fixes the issue.
It seems the second time a QWebPage is used, it tries to access to the browser cache (even if it has been disabled by configuration). But if the first QWebPage was not created in the main GUI thread, the cache is somewhat misconfigured and not usable.
To create the QWebPage in the main GUI thread I'm using a custom QEvent (QEvent of type User) that triggers QWebPage initialization and result fetching.


how to optimization magento 2.2.1 site?

Question: buddy:
   Recently i build a new magento 2.2.1 vesion site, but i feel it running very slow! I first contact the magento 2.0 vesion, so i have many things need to study.
   Now I want to know how to optimization the magento 2.0 vesion? I have via google to search the methods, but i don't found the good methods. Maybe i'm not intelligence, so i need your help or advice?
   Thank you very much!
Comment: can you provide site link I will check and provide a solution for performance
Comment: How slow is it for you? My configuration is apache on Ubuntu, PHP 7.1 with opcache + xdebug, Magento 2.2-dev in developer mode with generated static content and compiled DI. The homepage loading takes about 2secs, the slowest page is checkout page - takes about 7secs. I don't use Varnish, Redis, etc. for developing and the Magento app is pretty fast.
Comment: Hi, Rma:This is my site supwatch.com    maybe you can found some questoin! thank you very much!
Answer: Magento is fairly slow to begin with and requires a fair amount of resources.
"Magento 2 is not slow. It simply requires you to do proper tuning of your environment before it is working as it was designed to work." - Jisse@Yireo (https://www.yireo.com/blog/1842-best-performance-for-magento-2-development)
I've used the below on sites and they seem to be performing a lot better:
I would strongly recommend the use of Varnish on Magento 2 as it comes built in with the system - http://devdocs.magento.com/guides/v2.2/config-guide/varnish/config-varnish.html
Any 3rd party modules you have installed require a full review to find any cacheable="false" flags within XML on a block as this invalidates the entire page and not just that individual block, more info -
 http://devdocs.magento.com/guides/v2.2/extension-dev-guide/cache/page-caching.html
Setting up Redis for Session/Cache storage is also a benefit and doesn't take - http://devdocs.magento.com/guides/v2.2/config-guide/redis/config-redis.html
Lastly, don't flush/clear your cache every time you make a change! It forces Magento to re-generate all of that data. If you make a config change then only clear the Configuration cache. Any product changes you make should automatically send a purge request for that page in Varnish once setup thus avoiding performing full cache flushes on the FPC cache.
Edit - Further suggestions:
You can try installing https://github.com/magehost/performance-dashboard to get a performance dashboard on your site and can help you in setting up Magento 2 in an ideal way
Put your site through https://run.mage.coach/ and see what it comes back with, suggests performance benefits for you to implement.
Comment: Hi, Matt: This a great advice. I have see it . Thank you very much!
Comment: Hi @nextion, glad it helped! I've amended my answer with a few more resources that might help you.
Answer: By default Magento it's pretty robust and needs a lot of resources.
A first step in optimising Magento could be using Redis for page caching and session storage.
More information about this can be found in the official docs.
http://devdocs.magento.com/guides/v2.0/config-guide/redis/config-redis.html
Good Luck.
Answer: For deferring JS use a below extension.
https://marketplace.magento.com/bitware-speedenginedeferjs.html

how to optimization magento 2.2.1 site?


Some apps I'm finding only on iTunes, isn't there a way to buy in directly on my iPhone/iPod touch?

Question: Some apps (e.g. Angry Birds) I'm finding only on iTunes, isn't there a way to buy in directly on my iPhone/iPod touch?
Answer: It is very likely that the iTunes store in your country (Brazil after your profile) does not have all the apps from the US AppStore. Developers can choose if they want to make their app available in all or just some countries. Since the website of Apple shows the content of the US AppStore by default it might have led you to believe that you can buy the app with your account.
Comment: +1 Stores are country-based. This has caused a huge uproar, for example, in the Canada store because you can't get the French-language Scrabble as it's only available on the iTunes France store.
Answer: If @Andris got your problem right then, if you live in Brazil, you have the same problem I have. :-)
I mitigate it having a second account in the US Store. That allows me to download free stuff that is only available there (games and music apps like Shazam), and when I wish to buy an app I buy an iTunes Gift Card in eBay.
Another solution is moving your account to the argentinian store, which has a more "relaxed" policy and allows apps that doesn't appear in the brazilian store. I've never tried that, but I was told that you can create an account there with a credit card that has a billing address in Brazil. That is not accepted in the US and UK stores, for example.
Comment: Nice tip about the iTunes Gift Card.
Comment: There's one more thing to Brazil app store quite unique to most of the rest of the world stores... Games are forbidden. The only games you see in there are cleverly not categorized as such. I know this because the company I'm working on had this exact problem releasing its game in Brazil plus about 3 other countries.
Comment: There isn't even a Games category in the brazilian store. It's a shame.
Answer: Have you checked that you are logged in with the same account in both stores? Itunes sometimes doesn't have all apps available in all regions and you can have more than one account in the same library. If you are not logged in with the same account, I'd suggest you do login with the same account in both devices.
Comment: The answer above has it right.
Comment: I never logged in to iTunes, I use linux, I just saw in the website.


The task of interpreting the Word of God - The Pope

Question: CCC Article 2, 100 (Page 35):
"The task of interpreting the Word of God authentically has been entrusted solely to the Magisterium of the Church, that is, to the Pope and to the bishops in communion with him."
What exactly does this mean?  What does interpreting the Word of God imply?
Answer: This means that the Magisterium of the Church is used to specify to the People of God and to the world how, exactly, the Word is to be applied to our daily lives:

The Roman Pontiff and the bishops are "authentic teachers, that is, teachers endowed with the authority of Christ, who preach the faith to the people entrusted to them, the faith to be believed and put into practice." The ordinary and universal Magisterium of the Pope and the bishops in communion with him teach the faithful the truth to believe, the charity to practice, the beatitude to hope for.

(Catechism of the Catholic Church paragraph 2034; the quote is from Lumen Gentium, section 25.)
This echoes and explicates paragraph 890 of the Catechism:

The mission of the Magisterium is linked to the definitive nature of the covenant established by God with his people in Christ. It is this Magisterium's task to preserve God's people from deviations and defections and to guarantee them the objective possibility of professing the true faith without error. Thus, the pastoral duty of the Magisterium is aimed at seeing to it that the People of God abides in the truth that liberates.

In other words, it is the task—the pastoral duty—of the Pope and the other bishops in communion with him to watch over their flocks, to ensure that what the People of God believe and practice is in accord with the Word of God as it appears in the depositum fidei, the "deposit of faith" given us by God through Jesus and the Holy Spirit. To do so, they must pray and think over what the Word means, and what it implies for Catholic life, so that they can pass on appropriate beliefs, practices, and teachings to the Church. This is the "interpretation" mentioned in the Catechism.
Comment: Importantly, it expressly forbids a lay person from offering direct explication and interpretation of scripture, limiting that ability (gifting) only to bishops. Technically, not even a priest can offer direct interpretation and can only teach what the bishops teach as opposed to the Protestant concept that ordinary people can understand, explicate and debate what the authors (and Author) of scripture teach.
Comment: As something of an aside, it's interesting to observe that the infamous "Galileo Affair" was not a science/church conflict but, primarily, Galileo conflicted with the Catholic church because he offered alternate interpretations of scriptures that were at the time taken to mean the Earth was stationary at the center of the universe (that and he ridiculed the Pope with one of his "fictional" characters in a thinly veiled manner, which was just bad politics).
Comment: @LawrenceDol Good point - even theologians don't have that ability, though the Catechism says that the Magisterium is exercised "*with the help of* the works of theologians and spiritual authors" (para 2033). Let me see how I can add that in.
Comment: @LawrenceDol, and now slowly we can see that Galileo was wrong and the church was right. https://www.youtube.com/watch?v=p8cBvMCucTg
Comment: @Grasper: Well, I think I'll not wait with bated breath on *The Principle*; and I am an unabashed (old Earth) creationist. I think the entire philosophical premise, that being there is some requirement that we be at the physical center of creation, is deeply flawed.
Comment: "Importantly, it expressly forbids a lay person from offering direct explication and interpretation of scripture, limiting that ability (gifting) only to bishops."


Which European country sent the most slaves to the Americas?

Question: I'm asking for a history project; I have searched online, but have been unable to find an answer.
Comment: You should explain what you are looking for. Is the country defined as A) the country receiving (buying) the slaves? B) the nationality of the ship? C) the nationality of the captain of the ship? D) the country owning the factory in Africa?
Comment: Writing a question in a title is courteous; it demonstrates clarity and focus, communicates what you want to know, and helps readers find questions they want to research.
Comment: "Sending" is the act of dispatching something (somebody) on its way. So your question means "which body in Africa* dispatched most slaves to the Americas". Which is not the same thing at all as who transported them or who owned the ships or who crewed the ships or who received them at the other end. *I assume you mean Africa?
Comment: Writing a question in a title is a terrible practise. It shows a total lack of respect for people reading your question.
Comment: @SJuan76 Your (A) is obviously wrong: why would somebody write "send" if they meant "receive"? (C) seems completely irrelevant.
Comment: I think there's a fundamental problem with the question, in that it assumes the slave trade was run by nations, instead of by individuals & companies.
Answer: Portuguese ships carried more slaves to the Americas than any other flag carrier, but the numbers cited include Brazilian carriers
Although the time periods for the two sources cited are different, both include the years when the large majority of slaves were transported
Number of slaves Embarked (E) & Disembarked (D), 1501 to 1866

Portugal / Brazil    (E) 5.85 million, (D) 5.10 million Note: Brazil only became independent in 1822, by which time  the numbers embarked / disembarked were 4.34 million / 3.82 million
Britain              (E) 3.26 million, (D) 2.73 million
France               (E) 1.65 million, (D) 1.38 million
Spain / Uruguay      (E) 1.06 million, (D) 0.88 million
Netherlands          (E) 0.55 million, (D) 0.48 million

This (older) source gives different numbers, but the top two flag carriers are the same.
Number of Slaves Transported by each European Country, 1440 to 1870

Portugal / Brazil    4.65 million
Britain              2.60 million
Spain / Cuba         1.60 million
France               1.25 million
Netherlands          0.50 million
Comment: @RonJohn Hitchhikers?
Comment: @RonJohn We only brought the pregnant women accross the ocean
Answer: Wikipedia has a table of Destination of enslaved Africans (1519–1867):
<code>Destination                                           Percentage
British mainland North America                             3.7%
British Leeward Islands                                    3.2%
British Windward Islands and Trinidad (British 1797–1867)  3.8%
Jamaica (Spanish 1519–1655, British 1655–1867)            11.2%
Barbados (British)                                         5.1%
The Guianas (British, Dutch, French)                       4.2%
French Windward Islands                                    3.1%
Saint-Domingue (French)                                    8.2%
Spanish mainland North and South America                   4.4%
Spanish Caribbean islands                                  8.2%
Dutch Caribbean islands                                    1.3%
Northeast Brazil (Portuguese)                              9.3%
Bahia, Brazil (Portuguese)                                10.7%
Southeast Brazil (Portuguese)                             21.1%
Elsewhere in the Americas                                  1.1%
Africa                                                     1.4%
</code>
So... Portugal then?
Comment: Hm. Portuguese as destination is on thing, but who sailed the ships? The Spanish, the British, the French?
Comment: I thought that each colonial power (more or less) had their own ships & African bases. Did the Portuguese not have ships?


Modal form with CTools opened in several different pages

Question: I have a working module which opens a modal form with CTools. However, I must use the URL example.com/mymodule/page . There the module creates the link which opens the modal window with the form. How can I use the link in other pages? I have tried to just put the link and it does not work, it redirects to the page of the link (example.com/mymodule/nojs/) instead of opening the modal window.
Comment: The Anchror tag needs some special classes, and the modal JS needs to be added to the page first. Also, the page should return valid Ajax commands instead of raw HTML or render array.
Comment: I have added in template.tpl.php the following: ctools_include('modal');ctools_modal_add_js(); and the source code lists the same css and javascript. The ahref has the modal classes. But still it doesn't work. What makes me crazy is that it doesn't even open a popup.
Comment: What do you mean ahref has modal classes? What classes exactly? I think it should be `ctools-use-modal` plus the modal theme name. Also, check the `Drupal.ajax` in Firebug DOM inspector. you should see the href value of the link there if Ajax is set correctly.
Comment: It is exactly that class ctools-use-modal. I thought I understood the process. I click on the link, as it is modal and has the class jQuery sees as modal, instead of redirecting, opens a new window in modal form, and when the URL is called, Drupal makes the Ajax call to retrieve the form. So I simply put the link in another page and it does not work, even it does not open in modal, which is the most absurd thing.
Comment: This is unfortunately not the case. Modal JS scans the page (works as a JS behavior, so it's called on document ready event AND after an Ajax call) for the matching links and registers the Ajax object in Drupal.ajax. Adding or removing the class later in a particular anchor tag will not make a difference because Ajax functionality is already bound to it. Are you adding the class to anchor tags using JS? Can you see Drupal.ajax stuff?
Comment: I am adding the complete URL link in the page--*.tpl.php. I can see Ajax because I have a pager which is using Ajax and is working. I am going to see the difference at low level with Firebug as you suggest and will report back. Thanks a lot for your patience.
Answer: I have finally solved the problem and now everything works: the modal window, the form and the submit, sending the email in final step. The problem was that the raw URL included the class ctools-use-modal-processed and apparently that simple css was making it not work. Now more or less understand the process, thank you for your help, it has been very valuable.


How should (currency) tags be defined?

Question: I haven't looked too much at the tags in use, but noticed an inconsistency in the currency tags for this question -- 'usd' and 'british-pound'. I thought I'd create a meta question to discuss.
Comment: in addition to what Robert mentioned, you can also flag for moderator attention and we'll have a look!
Answer: Did one of the other stack exchanges use both the abbreviation and the name as the tag like this:
usd-us-dollar,  gbp-british-pound, etc.
Comment: I just established a new tag 'cad-canadian-dollar' here:  http://money.stackexchange.com/questions/5558/where-can-i-open-a-bank-account-in-canadian-dollars-in-the-us ... we should change the other currency tags over time to match.
Comment: +1.  Those have the advantage of being keyword rich.  There might be a length limitation on some obscure ones, but the major ones all probably fit.
Comment: I've changed USD and GBP to the new style tag, and added a couple of more synonyms (noticed you had at least a couple there already.)
Comment: Just added eur-euro and a synonym from euro to eur-euro.
Answer: It looks like the tags have already been edited. What are your suggested changes?
Any user with 200+ reputation can edit tags. Since you do not yet have sufficient reputation, you can make your requests here (as you did) or comment on the individual posts.
Comment: He can also flag for moderator attention with only 15 rep.
Answer: Currencies have standard names (usd, gbp, etc.) so maybe standardize on them and alias other names ("us-dollar", "british-pound", "uk-pound") to them?

How should (currency) tags be defined?


Data Loader updates Date Value incorrectly

Question: I am loading data into Salesforce using data loader,  After loading data I found that all the data value in Salesforce is updated with one day less.
i.e if my csv had date value 2016/08/31 , In Salesforce it got updated with 2016/08/30.
My PC is in IST time zone and my Salesforce instance belongs to EST timezone and the user credentials Timezone used in data loader is '(GMT-04:00) Eastern Daylight Time (America/New_York)'.
Please let me know what went wrong.
Thanks,
Indrasen.
Comment: I'd -1 this for lack of research because the answer was ascertained via a simple googling ...but I'd also +1 this for the inclusion of relevant details about the 3 separate time zones. In the end, I still downvoted because this question has [been asked, and answered, before](http://salesforce.stackexchange.com/questions/8010/apex-data-loader-is-loading-previous-date?rq=1) (it's the second result in the related questions for me at time of writing). I will say that the answer on this question is better.
Answer: From Salesforce help
Why do date fields import incorrectly when I use the Data Loader?
When importing date fields using the Data Loader, sometimes dates import incorrectly because the Data Loader converts the date specified in the imported .csv file to GMT. If your machine's time zone isn't GMT or if your machine's clock adjusts for daylight savings time (DST), your dates may be off by a day.
To prevent the Data Loader from adjusting the date when it converts to GMT, directly change the format of cells containing dates to reflect the native time zone.

Open your .csv file in Microsoft® Excel®.
In each cell in which you entered dates, add hour data to represent the  native time zone. For example, if the date is June 9, 2011 and the time zone is GMT+8,enter June 9, 2011 8:00. Excel will reformat this to 6/9/2011 8:00.
Right-click the cell in which you entered dates, and click Format
    Cells.
Click Number | Custom.
In Type, enter yyyy-mm-ddThh:mm:ss.sssZ. For example, if the cell was 6/9/2011
    8:00, it's now 2011–06–09T08:00:00.00Z.

From Knowledge Article
How can I ensure my dates are correct when loading with the Data Loader?
When loading data into date fields such as Opportunity Close Date using the Data Loader, the date displayed in the application is sometimes one day earlier than the date in the file.
The reason for this is that fields such as Close Date are actually date/time fields.  When a date is loaded without specifying the time, the time is defaulted to 00:00 - midnight.  When another user is in a time zone which is behind the current user's time zone, the date will show on the previous day.  For example:
20 August 2008 00:00 in Paris is 19 August 2008 23:00 in London
Similar issues can arise when daylight savings time begins or ends.
Two simple solutions to this are:
1) Specify a time as well as a date when loading dates using the Data Loader.
or
2) Switch your PC's time zone to Hawaiian time before starting up the Data Loader.

From Knowledge Article
"Date" and "Date Time" format in Data Loader and API
Data Loader can have have trouble importing changes to the "Date" and "Date Time" Data Type fields when your CSV file import doesn't use specific formatting or correspond with your org's time zone settings.
Here's the correct formatting to use so you can avoid errors and frustration:
"Date" field acceptable formats
YYYY-MM-DD
YYYY-MM-DD hh:mm:ss
YYYY-MM-DD hh:mm:ss
YYYY-MM-DDThh:mm:ssZ
YYYY-MM-DDThh:mm:ss.sssZ
"Date Time" field acceptable formats
YYYY-MM-DD hh:mm:ss
YYYY-MM-DDThh:mm:ssZ
YYYY-MM-DDThh:mm:ss.sssZ
Example scenarios
Scenario: If your org's time zone is set as "China/Taiwan time zone GMT+8":
"Date" and Data Loader time zone is GMT+0, GMT, or blank
Your example data in your import spreadsheet can be either:
2011-01-10
2011-01-10 00:00:00
2011-01-10T00:00:00Z
2011-01-10T00:00:00.000Z
"Date" and Data Loader time zone is GMT+8
Your example data in your import spreadsheet must be either:
  2011-01-10 08:00:00
2011-01-10T08:00:00Z
2011-01-10T08:00:00.000Z
Note: If you set the hh:mm:ss to 00:00:00, the Import Date data in Salesforce will display the previous day ('2011-01-09' instead of '2011-01-10').
"Date Time" and Data Loader time zone is GMT+8
Your example data in your import spreadsheet must be either one of the below options in order to have the Date Time display exactly what you imported in spreadsheet:
2011-01-10 XX:XX:XX
2011-01-10TXX:XX:XXZ
2011-01-10TXX:XX:XX.XXXZ
Additional information about these formats
XX:XX:XX or XX:XX:XX.XXX stands for the variable time you key in.
The "T" in these strings indicates the beginning of the time element.
"Z" is a special GMT designation.
This information is only applicable for the latest version of the Data Loader
Comment: I was about to post the same thing. For what it's worth, Salesforce could stand to be a lot more clear about when this issue can occur. The first article mentions the local machine time, while the second article mentions org default time. From the OP's description, it would appear that the timezone setting for the user and the org default time zone are both ignored when using Data Loader.
Answer: Rather than changing all of your csv data, try to go into the settings of Apex Data Loader and change the timezone to GMT
Answer: Try using 'America/Los_Angeles' timezone for data loader as i also got the same issue but then i changed timezone as'America/Los_Angeles' and then data is inserted correctly
Answer: I encountered a similar problem with date appearing a day ahead after the change from GMT to British Summer Time. I believe this may be due to the date selection in Excel.
In Excel, highlight the date column and right-click.
Select Format Cells... and select Number and Date
Rather than select the first type that looks right for your Language (Location), the description at the bottom explains that "date formats that begin with an asterisk respond to changes in regional date and time settings that are specified for the operating system".
Make sure you use a Type without an asterisk. See image below:


What is the simplest way to write data to CartoDB using Python?

Question: I'm trying to write a function in Python that will use the CartoDB API to write data to one of my tables. Does anyone have a simple example that shows how to do this that I can use to start?
Answer: Writing data through the API is pretty simple. Here is the most basic,

Suppose we have two variables already, how you get them is up to you,

username = 'cartodb-user-name'
apikey = 'MY-CARTODB-API-KEY'

Next, lets create an INSERT statement to use

insert = "INSERT INTO my_table_name (the_geom, measure) VALUES (CDB_LatLng(43, -120), 22.0)"

Create the URL endpoint for our account API

url = "https://%s.cartodb.com/api/v1/sql" % username

Create an object containing the parameters of our request

params = {
    'api_key' : apikey, # our account apikey, don't share!
    'q'       : insert  # our insert statement above
}

Send the request using urllib2

req = urllib2.Request(url, urllib.urlencode(params))
response = urllib2.urlopen(req)

SETUP: You should have a couple libraries imported in your python script
import urllib
import urllib2

BONUS: Batch inserts are wayyyy better than single line inserts.
Here is an example of a multi-row (3) insert strategy. I use an array to initially store all my row values. Each row value is a comma delimited list, wrapped in parentheses and stored to the array,
rows = [
    "(CDB_LatLng(10, 10), 1.0)",
    "(CDB_LatLng(20, 12), 1.4)",
    "(CDB_LatLng(30, 14), 1.2)"
]

insert = "INSERT INTO my_table_name (the_geom, measure) (VALUES %s)" % ','.join(rows)

Using this, I've wrapped all 3 rows into a single http request. It works faster all around and is highly recommended. From personal experience 100-250 rows at a time works really well.
Comment: @mapbaker's comment below is true too! i could have swapped out a bunch of this for the cartodb library, just figured i'd go raw in this case
Answer: There is a python library for CartoDB... I think it would work with the SQL API.
Answer: Here's an example script that I wrote a while back. It basically implements what andrewxhill wrote above, but uses the "requests" library instead of urllib.
It batches together inserts to do 1000 at a time, then uses the API to do the inserts.
lasbbox2cartodb.py
The script loops over a set of Lidar files in subdirectories, and inserts the bounding boxes for the lidar files into CartoDB.


How can I play Dying Light in Germany?

Question: The game is not available for sale here, and CD keys apparently will not activate on steam from this region. Could I activate a key on the steam website using Hola Unblocker, or would the gam refuse to download after being added to my account like Wolfenstein the New Order? Is there anything else I can do (that doesn't involve a vpn), or am I just going to have to import the PS4 version?
Comment: For what it's worth, owning the game isn't illegal here as it hasn't been banned. It just hasn't been offered for sale.
Comment: I think it's possible to have someone outside germany buy it and save it as steam trade and send it to your stealm account but i'm not a 100% sure though
Comment: Although I sympathize, I think this question might be against the rules of Arqade
Answer: As this game is not prohibited to run in Germany, you can ask someone from a country where it is available to gift or trade it to you. You can then accept the gift and play it normally. This is an intentional loop hole in Steam and works with any Game that does not have the prohibitedToRunInCountries or onlyallowrunincountries flags on it's config, like seen here. This flag prevents you from playing the game while being connected with a German IP.
The advantage of a Gift is that you do not break the Steam Subscriber Agreement, which you do when activating such a game via a Proxy/VPN.
However, be advised that the developer could change his opinion anytime, but I have never actually encountered that and Techland has left the loop hole open for us with Dead Island 1+2 too. with DI1 it was even possible to activate imported Game Keys.
Source of knowledge: I own nearly every Game on Steam I have as uncut version, gifted by an american friend, e.g. South Park.

How can I play Dying Light in Germany?


What does the ATR72-600 MFD System display look like?

Question: I'm curious how MFD System display looks in real life in ATR72-600, especially electrical mode. I've found three different images showing it, but they seems to be ambiguous. Last one attached comes from FCOM, two others from other docs. Which one is closest to real life? Buses symbols should be as rounded corner rectangles or simple one? States (like "OFF", "SHED") should be out or inside rectangles? Maybe it depends on software version or some specal mode? Maybe someone has real life photos showing it? Any info is highly appreciated.
Comment: Two "black" images come from "User guide for Engineers" from Thales Avionics, last one as i said from FCOM.
Answer: For me, it looks like the first picture is something like a screenshot. It looks real. (A bit blurred and pixelated)
The second one looks like a graphic made in a graphics program. There can be small deviations from the original screen design, because it's only for informational purposes.
The third one is a black/white graphic that is made for printing (in the FCOM). I think it should be showing the real MFD quite close to reality because pilots must see it as in real life. But this saves printer color and has more contrast.
I am pretty sure, the first one is a real screenshot. It shows commonalities with the drawing in the FCOM and it looks real.
Answer: Two actual photos of the electrical systems pages (AC and DC respectively). Hope it helps.
Comment: Sorry for being late. Thanks for these priceless photos! Right now everything is much more clear and i could move forward with work ;).


How to properly do dua?

Question: I would just get on my knees and just start asking, but I have been told that I have to send blessings to the prophet (pbuh) or it won't be valid.
That I should thank Allah swt first then bless the prophet (pbuh), confess a sin and then start asking.
I just feel like I been making dua wrong.
Answer: As a hint what you are describing are AFAIK the recommendations of ibn Qayyim al Jawziyah (well i haven't heard of confess a sin in those, but the rest was included) I only heard them in a khotba or maybe maw'idah, i have not read them so maybe I missed a point. But one point in your list is missing you should be sitting or kneeing in the direction of the qiblah.
First of all dua' is something between you and your creator, so if it comes from the heart you may have done it well and be aware that dua' is worship.

But as in dua' we are addressing Allah to ask HIM something it would be nice and more "polite" to start by praising HIM and being thankful to him, this is based on the hadith from Musnad al-Imam Ahmad which especially hanbali and salafi scholars seem to put a strong emphasize on, even if it seems to have some weaknesses:

"Every important word or matter that does not being with remembrance of Allah is maimed." (see here a fatwa on the qualification)

But it in this case it is supported by the Quran (7:180) which is recommending to ask and invoke Allah with his beautiful or best names. And ahadith like here in jami' at-Tirmidhi or in sunan abi Dawod.

There's a also an other Hadith from at-Tabarani's awsat where we are strongly recommended to send blessings to our beloved Messenger (peace be upon him):

Every du'aa' is kept back until you send blessings upon the Prophet (peace and blessings of Allaah be upon him

There's a hadith recommending to face the qibla quoted in sahih Muslim and jami' at-Tirmdihi.
Raising hands is also recommended (see also how here).
If one asks Allah he should be certain of being answered.
Asking frequently and shouldn't get tired of asking or seek a hasty response. A believer should ask his Creator for whatever he wants or comes in mind of the good things in this life and the Hereafter. He should also be firm in his du'aa.
One should ask beseeching, with humility, hope and fear. As Allah said (7:55)

Call upon your Lord in humility and privately; indeed, He does not like transgressors.

There are also ahadith recommending to repeat the dua' three times, others who say that a dua' wouldn't be accepted from a person who eats haram (that means who earns haram and feed himself and his family from this earnings), and as the verse above seem to show one should Ask Allah privately.
For more details read this fatwa.
And Allah knows best!
Answer: It is "Mostahab" to begin Duaa by praising Allah, then pray upon the Prophet, peace be upon him, then to ask what you wish:

The Messenger of Allah (ﷺ) heard someone supplicating after his prayer
without praising Allah and without supplicating Allah for the Prophet
(ﷺ). With regard to him, the Messenger of Allah (ﷺ) said, "This man
rushed." Then he called him and said, "When any one of you have
performed Salat (prayer) and wants to supplicate, let him praise Allah
first then glorify Him in the beginning and then he should supplicate
Allah for me. Then he may supplicate for whatever he likes." [Abu
Dawud and At-Tirmidhi].

Also Umar bin Al-Khattab narrated:

"Indeed the supplication stops between the heavens and the earth.
Nothing of it is raised up until you send Salat upon your Prophet."
Jami` at-Tirmidhi 486

Allah knows you did not know this before, so I hope your previous Duaa is OK.

How to properly do dua?


Self-interest leading to the public interest via the invisible hand?- Adam Smith

Question: Adam Smith argued that the pursuit of self-interest will lead to the public interest - the public good - by the mechanism of the invisible hand. Does this argument hold only for a perfect economic system and in a business context? Does this mean we should focus only on self-interest in doing our jobs and activities ?
Comment: I don't think Smiths view of economics can be understood without reference to his theory of moral sympathies as outlined in his book *The Theory of Moral Sentiments*.
Comment: @ Geoffrey Thomas. It is nice to see you again here
Comment: @Mozibur Ullah. I absolutely agree and my answer involves essential reference to TMS.
Comment: @xyzabc. Thanks - glad to be back and to see another question from you. Best - GT
Comment: @GeoffreyThomas: I had noticed, and that's why I upvoted it. Great answer. ;-).
Comment: @Mozibur Ullah. Much appreciated. Best - Geoff
Comment: @Philip Klöcking. Thanks for the presentational changes. Much appreciated : GT
Comment: Weisskopf wrote an interesting book (within the capitalist realm),a university library or good public library would have it:  Walter Weisskopf, Alienation and Economics, E.P. Dutton, NY (1971).
Comment: 1970s stuff:  Letter exchange: http://www.nybooks.com/articles/1974/03/21/alliance-with-galbraith/
Answer: Smith is writing in the context of a capitalist market economy. He makes three major claims :
▻ THE GENERAL ECONOMIC CLAIM
The basic idea is that if each individual pursues his or her own interest, without regard to the public interest, the 'invisible hand' of the free market will promote the public interest. This appears a paradox. Let's see how Smith tries to remove the paradox :

'As every individual, therefore, endeavours as much as he can both to employ his capital in the support of domestic industry, and so to direct that industry that its produce may be of the greatest value, every individual necessarily labours to render the annual revenue of the society as great as he can. He generally,
indeed, neither intends to promote the public interest, nor knows how much he is promoting it. By preferring the support of domestic to that of foreign industry, he intends only his own security; and by directing that industry in such a manner as its produce may be the greatest value, he intends only his own gain, and he is in this, as in many other cases, led by an invisible hand to promote an end which was no part of his intention.' (Wealth of Nations, 1776, IV.ii.9)

So, for instance, if I pursue only my own economic interests, investing my capital in a free market, I will prosper only if I produce goods and services that consumers want. I reap the economic rewards and this is all that matters to me but the public interest is served. I have to employ my capital efficiently in order to make a profit; this is in the public interest as much as the resulting profits are in my own. The 'invisible hand' is just the mechanism of a free market.
Smith can also be less abstract and more homely in talking about the promotion of the public interest by the pursuit of self-interest:

'It is not from the benevolence of the butcher, the brewer, or the baker, that we expect our dinner, but from their regard to their own interest. We address ourselves, not to their humanity but to their self-love, and never talk to them of our own necessities but of their advantages. (WN I.ii.2)

In a free market the butcher, the brewer and the baker are business from self-interest but they will fail unless they provide quality goods at competitive prices - this promotes the public interest.
I am not presenting the situation in a sophisticated economy but trying simply to convey Smith's basic point. We'll see next how he complicates the picture.
▻ EXCEPTIONS TO THE GENERAL ECONOMIC CLAIM
Smith distinguishes three economic classes : (a) labourers, (b) landlords, and (c) manufacturers and merchants. He is doubtful whether the invisible hand argument works very effectively in the case of manufacturers and merchants :

'The interests of this third order [those who live by profit], therefore, has not the connection with the general interest of society as that of the other two [labourers and landlords]. . . . The proposal of any new law or regulation of commerce which comes from this order [those who live by profit], ought always to be listened to with great precaution, and ought never to be adopted till after
having been long and carefully examined, not only with the most scrupulous, but with the most suspicious attention. It comes from an order of men, whose interest is never exactly the same with that of the publick, who have generally an interest to deceive and even to oppress the publick, and who accordingly have, upon many occasions, both deceived and oppressed it. (WN I.xi.)

Smith offers an explanation for why the self-interest/ public interest equation readily fails in the case of merchants and manufacturers but to go into this would take us into economic analysis. The main text is WN I.xi. Suffice to say that for whatever reason Smith does not think there is an automatic interlock between the pursuit of self-interest and the promotion of the public interest across the piece.
▻ THE MORALITY OF SELF-INTEREST
Smith does not promote a morality of self-interest. He does not endorse the pursuit of self-interest in general. Self-interest serves a particular purpose in the context of economic activity, and even there only under free market conditions and with a cautious eye kept on merchants and manufacturers. The pursuit of self-interest is morally neutral. Smith invokes a doctrine of 'natural liberty' to block any automatic right of the state or society to interfere with it as such. But his view of the moral life as set out in 'The Theory of Moral Sentiments'.
Smith regarded viewed sympathy as the foundation of virtue. In his ethical theory he is not concerned with the promotion of the public interest. The virtues are to be pursued for their own sake; and the central moral virtues derive from sympathy (a concept he took over and re-worked from David Hume). Sympathy is the root of beneficence (altruism or concern for the interests of others), self-command ('propriety') and justice. Where his economic theory uses the metaphor of the invisible hand, his ethical theory employs that of the impartial spectator :

'We either approve or disapprove of the conduct of another man according as we feel that, when we bring his case home to ourselves, we either can or cannot entirely sympathize with the sentiments and motives which directed it. And, in the same manner, we either approve or disapprove of our own conduct, according as we feel that, when we place ourselves in the situation of another man, and view it, as it were, with his eyes and from his station, we either can or cannot entirely enter into and sympathize with the sentiments and motives which influenced it. We can never survey our own sentiments and motives, we can never form any judgment concerning them; unless we remove ourselves, as it were, from our own natural station, and endeavour to view them as at a certain distance from us... We endeavour to examine our own conduct as we imagine any other fair and impartial spectator would examine it. If, upon placing ourselves in his situation, we thoroughly enter into all the passions and motives which influenced it, we approve of it, by sympathy with the approbation of this supposed equitable judge. If otherwise, we enter into his disapprobation, and condemn it.' (Smith, TMS, 1759, III.1.2).

It is clear that there is no necessary coincidence between self-interest and the judgements of the impartial spectator. Whatever role Smith assigns to self-interest in the economic realm, it is not self-interest but sympathy adjudicated by the impartial spectator that dominates - to an extent does, and totally should - in the moral life.
Comment: Bear in mind that "any new law or regulation of commerce" itself alters that presumption of a free market, by giving some government agent the power to substitute his decision for the choices made by countless buyers and sellers in the marketplace.  The government has the power to compel a transaction in which one party (or more) will leave with less value (by his standards) than he began, but in a free marketplace, no transactions can occur unless all parties believe they benefit.  Thus, regulation confined to the punishment of force and fraud means the sum of all transactions benefit all.
Comment: @Monty Harder. Thank you for this comment. I don't think it runs counter to anything I say but it does make very clear a connexion, which I didn't make explicit, between new laws and regulations originating in the interests of 'this third order' and interference in the freedom of the market. I appreciate your drawing out the connexion so lucidly and cogently. Best - GT
Answer: Modern economic theory, especially game theory, provides many examples where the pursuit of self-interest leads to outcomes that are suboptimal from the perspective of the public interest.  The paradigmatic example is the Tragedy of the Commons, in which each individual, driven by self-interest, overuses the common resource, whereas everyone could have been better off if everyone had used it less.  Overfishing is a good modern example, as are many other examples involving the environment.  (Note that these are still business contexts.) In such cases, it is sometimes possible to realign the individual's incentives with the public interest via Pigouvian taxes.  But modern economic theory certainly doesn't support the blanket statement that the public interest is always best served by everyone pursuing their self-interest.


Is there a word or phrase to describe a person who doesn't want to engage in serious conversation with you?

Question: Something less roguish than "imp" or "wag." I'm thinking about a person who is perhaps a bit sullen or in need of some levity. The word or phrase would be better if it expressed how this person feels rather than labelling the type of person they are. Maybe a type of sentiment.
Comment: Have you considered that maybe the problem is you and not him?
Comment: I feel like it depends on the situation... maybe a boy is shy to talk to an attractive woman... maybe an employee is afraid to talk to his superior... maybe a liberal hates talking to conservatives...
Answer: Aloof.
adjective
not friendly or forthcoming; cool and distant.
conspicuously uninvolved and uninterested, typically through distaste.
http://www.dictionary.com/browse/aloof
Answer: What about diffident or one of its synonyms?

modest or shy because of a lack of self-confidence.
a diffident youth
late Middle English (in the sense 'lacking confidence or trust in someone or something'): from Latin diffident- 'failing in trust', from the verb diffidere, from dis- (expressing reversal) + fidere 'to trust'.
synonyms:  shy, bashful, modest, self-effacing, unassuming, unpresuming, humble, meek, unconfident, unassertive, timid, timorous, shrinking, reserved, withdrawn, introverted, inhibited; insecure, self-doubting, doubtful, wary, unsure, apprehensive, uncertain, hesitant, nervous, reluctant, fearful; self-conscious, ill at ease, ashamed, abashed, embarrassed, shamefaced, sheepish; mim; (informal) mousy — From Google Dictionary
Answer: My word shall be unforthcoming.
 It is carried by 4/5 dictionaries:

Collins English Dictionary
  adjective
not inclined to talk
  about something ⇒ she was unforthcoming about her past
Example
  sentences containing 'unforthcoming'

He sat at a small table,
  earphones and headset on the surface before him, an unforthcoming
  expression on his face. Smith, Evelyn E MISS MELVILLE REGRETS
He was
  an affable chap, though unforthcoming on personal matters. Fraser,
  Anthea THE GOSPEL MAKERS
Comment: Large chunks of quoted material should be placed inside block quote formatting. Also, it's easier to read posts if they are formatted using tools like italics, line breaks and bullets. I've edited your post to break up the solid paragraph.
Answer: withdrawn
From M-W:

socially detached and unresponsive :  exhibiting withdrawal :
introverted
Examples of withdrawn in a sentence:
He became more withdrawn after his
brother's death.
She was withdrawn as a child but is now more
outgoing.
Answer: There is an idiom common in AmE, in a funk (or a blue funk)

(chiefly North American) A state of depression:
  I sat absorbed in my own blue funk

Oxford Dictionaries Online
It tends to be used for a transitory condition rather than a chronic depression.
Answer: This person is down in the dumps.  It is usually a temporary condition,   for example:

I don't want to think about anything serious.  It's been raining for
  three straight days, my cat is sick, and I am down in the dumps.

down in the dumps, From The Free Dictionary:

unhappy. She's down in the dumps because all her friends are out of
  town.......
Also, down in the mouth. Discouraged, depressed, or sad, as in She's
  been down in the dumps ever since she lost the match, or What's wrong
  with him? He's so down in the mouth about everything. The noun dumps
  has been used for "a state of depression" since the early 1500s, and
  down in the mouth, alluding to the downturned corners of the mouth as
  a sign of misery, dates from the mid-1600s.


Is there a specific relation between sideslip angle and yaw rate OR how sideslip angle depend on yaw rate?

Question: Since, yaw rate is controlled via rudder and sideslip angle can also be controlled by rudder, I want to know if there is any dependence of sideslip angle on yaw rate in fly by wire aircraft as I am working on the SAS design of a/c lateral/directional dynamics?
Comment: Your question seems to be unclear with respect to its purpose. It might help if we knew what you are trying to find out. Can you describe your question a different way? I am assuming that you know what a sideslip is normally used to accomplish.
Comment: one is a rate and the other is an angle. are you asking about the relationship of a velocity w.r.t. a distance?
Comment: Hii...I am asking the relation in terms of direction ( +ve  or -ve). i.e. how  does positive/negative yaw rate relate to +ve/-ve sideslip angle?
Answer:
Since, yaw rate is controlled via rudder

No, yaw is controller by many things, and rudder is there mainly to compensate for them to keep the plane flying nose-forward.
The usual way to make a control system is that you control (with a PID controller):

Move elevator to target vertical (plane coordinates) acceleration.
Move ailerons to target roll rate.
Move rudder to target zero lateral (plane coordinates) acceleration. Lateral acceleration is measured by the ball in traditional cockpit.

Note that each axis is basically independent and rudder is only used to eliminate side-slip, which is proportional to the lateral acceleration unless you have asymmetric thrust or drag—and I have not heard of a FBW that would automatically correct for those conditions.
When flying with auto-pilot, the auto-pilot sets vertical speed target from altitude error and vertical acceleration from vertical speed error for the pitch and it sets roll from heading error and roll rate from roll error for roll axis. Autopilots don't set lateral acceleation targets at all—that is always zero.
That is why auto-land has much lower cross-wind limit—autopilot does not handle rudder, so it can't de-crab.
Answer: Sideslip angle β is the "sideways" angle of attack of the aircraft body. In a given time span, sideslip angle is the integrated signal of yaw rate, which is the integrated signal of yaw acceleration, which follows from the yawing moment and the inertia. This is the case in any aircraft, fly-by-wire or conventional control.
$r_{dot}$ = $M_β$ / $I_Z$
r = $∫$ $r_{dot}$ dt
$β$ = $∫$ r dt
Sideslip is an aerodynamic entity defined relative to air velocity (body axes), while inertial entities are defined in earth axes. A transformation matrix describes the relationship of the two axes systems. For flight behaviour the body axes form the frame of reference: a sudden side wind changes initial side slip angle at the start of our time interval, plus the moments acting upon the aircraft.
Comment: This answer is only correct under specific conditions (e.g. no wind) which you might want to spell out. As it is it is rather incomplete.
Comment: @koyovis Sideslip angle can change by windshear with no change in yaw when viewed from an earth frame of reference (which is where sideslip is most useful).
Comment: Meaning - Newton's law is incomplete?
Comment: Ah now I see what Peter means :)
Answer: No, there is no specific or dependent relationship between sideslip angle and yaw rate.
A momentary yaw rate can result in a slip, but a sustained sideslip maneuver will involve a zero yaw rate. Note that a yaw rate is a measurement of rotational velocity while a slip angle is a measurement of relative position.
Consider a momentary yaw rate brought about by rudder deflection with the wings held level. That momentary yaw rate will result in a slip of some angle (which angle will depend on a number of factors including but not limited to amplitude and duration of yaw rate), but to sustain a sideslip will necessarily require a zero yaw rate. That is to say, to fly in a sustained sideslip maneuver—as opposed to a slipping turn—the angular difference between the relative wind and aircraft's longitudinal axis must be maintained with a zero yaw rate.
While yaw rate or angle can be controlled by rudder, there are several other forces or control inputs that can affect or control yaw rate or angle. As one example, consider an asymmetrical thrust scenario involving a sustained sideslip and zero yaw rate. In that scenario, rudder input opposite the direction of the sideslip may be required to maintain the sideslip.
Comment: @Jonathan Walters Ok got that there is no specific relation but as you said " ...but to sustain that sideslip will necessarily require a zero yaw rate." How is it true in case of an uncoordinated turn, as it may have a constant yaw rate but still some sideslip angle.
Comment: @Swati As a maneuver, a [sideslip](https://en.wikipedia.org/wiki/Slip_(aerodynamics)#Sideslip) generally refers to an established slip with sideways movement and no rotation rate about the vertical axis. The terms `slip`, `sideslip`, and `forward-slip` are sometimes used interchangeably and I understand they can be confusing. You seem to be referring to a slipping turn which will involve a slip as well as rotation about the vertical axis.


How to install 7zip to extract rar files

Question: How do I install 7zip through Terminal to extract rar files?
Answer: I don't know why would you like specifically 7-zip's binary to extract RAR, but here we go:
To unrar files with... unrar:
sudo apt-get install unrar-free
unrar e some.rar

To extract rar files with 7-zip:
sudo apt-get install p7zip-full
7z x some.rar

e and x mean extract obviously.
Comment: instead of using zip, tar, unrar, etc. we could use the same tool (7z) with the same interface for all of them
Answer: You may use p7zip. And you can install p7Zip using command : sudo apt-get install p7zip.
To extract RAR archives, you'll need to install package "p7zip-rar", too.
Install it using : sudo apt-get install p7zip-rar
Or you can get it done in single command : sudo apt-get install p7zip p7zip-rar
Read p7zip manual for more information: man p7zip
Comment: Post-bounty note: This was the only answer that correctly mentioned the required package for 7zip to be able to extract rar files. `p7zip-rar` depends on `p7zip-full`, but the reverse is *not* true as assumed by other answers when bounty was started.
Answer: Use the following command to Install 7Zip:
$ sudo apt-get install p7zip-full

Extract files using 7zip:
$ 7z e example.zip

(Or use the x option instead of e to preserve file paths).
Compress files using 7zip:
$ 7z a compress.zip

For more information, visit the reference
Comment: I didn't come right with the accepted answer. This worked spot-on.


Make Woocommerce breadcrumbs show up using functions.php file

Question: I updated my Woocommerce site to version 3.4.5 and the breadcrumbs disappeared. I didn't make any changes to the site except the update to Woocommerce right after updating to the newest WP 4.9.8 version. I've tried many different potential solutions I found online using the function, add_filter & add_action calls, but none have worked so far. Everything I've seen has been to make changes or make the breadcrumbs invisible. I want to leave them styled just as they were before the update (which was the default), but have them show up on the catalog and single product pages again. I think I can do this in the functions.php file of my theme, but I'm pretty new to php and nothing I've tried has forced them to show up. When I view the code via the browser I can't even find a class for breadcrumbs or anything currently, but the single product page within the new Woocommerce update looks just like the one from the version I updated from.
Any help is seriously appreciated -- thanks!
Answer: Does your single-product.php contain this?
<code><?php
    /**
     * woocommerce_before_main_content hook.
     *
     * @hooked woocommerce_output_content_wrapper - 10 (outputs opening divs for the content)
     * @hooked woocommerce_breadcrumb - 20
     */
    do_action( 'woocommerce_before_main_content' );
?>
</code>
Comment: Yes it does contain that.
Comment: Please advise with site link so people can help you further.