Can film be considered to have infinite resolution as opposed to digital sensors?

Question: Camera sensors have an specific number of cells,and their resolution depends on this amount of cells. But film does not have this "units" of sensible material; So, does the size of the particles of the film's light reacting coatings determine its resolution, or can it be said that film has an infinite resolution?
Comment: Actually, nowadays high-end digital cameras have better resolution than film.
Comment: @MichaelBorgwardt - that depends on the film in question. We're nowhere near Kodak Technical Pan yet, for instance, and only just within spitting distance of Ektar 25. Whether or not anyone *needs*, or needs to deal with, half-gigabyte full-frame 35mm raw files, though, is another question.
Comment: Look up the tech specs on some films and you will see they have a resolution rating, usually expressed in lines/mm. For example, the very fine grained Kodak Panatomic-X is rated around 200 lines/mm if I remember right, but this comes at the expense of sensitivity. However, if your lens can't resolve that, then in effect the film has infinite resolution in that application. This is why Pan-X or one of its close relatives was often used to measure lens resolution.
Comment: Further Reference: See the film "Blowup" by Michelangelo Antonioni. :-)
Comment: we also need to remember that lenses don't have infinite resolution, either. So even if the film or sensor had infinite detail, the image sent to it through the lens won't.
Answer: No, you cannot say it has infinite resolution, despite what CSI may have people believe :)
A film particle puts limits on how fine details can be resolved. It gets complicated though because film has grains of different sizes. Every frame is composed of grains of different sises and they are intermixed. Larger particles are more sensitive to light and used to render details in shadow areas while smaller grains are for keeping details in highlights.
Film would not really work if all grains would be the same size.
Comment: and to complicate matters further, the actual grain size doesn't say everything, grain shape and distribution also matter.
Comment: [Here's a microscopic photo](http://static.photo.net/attachments/bboard/00R/00RSSV-87517584.jpg) of a normal photo where you can see the grains.
Answer: The size of light reactive particles (grains) certainly is a major factor in a film's resolution, and it definitely can be said that film does not have infinite resolution.
The resolution of film and digital sensors is generally specified in the same way, by it's modular transfer function. And the photo-site count of a sensor (i.e. number of pixels) just serves as an approximation of it's actual resolution.
Answer: On most digital cameras, if one cranks the ISO up to maximum, one will nominally have the same resolution as at a lower ISO setting, but the picture will have a lot more noise (parts of the picture which appear lighter or darker than they should).  Such noise will make it harder, or in some cases impossible, to observe all of the fine details in a picture.  The only digital cameras which do not have this behavior are those which restrict the range of ISO settings below the point where noise would become a problem.
Film can generally be thought of as having no hard resolution limit beyond the fact that it has a certain amount of noise; the more one magnifies the image on the film, the more apparent this noise will become, to the point that it may dominate everything else.  Much as reducing the ISO setting of a digital camera can reduce noise, likewise with selecting a lower ISO film.  If one has a certain amount of tolerance for noise, one can for a given kind of film and set of exposure conditions, define the maximum resolution where the noise would remain tolerable.  The more noise one can tolerate, the higher the "usable" resolution.
There are, of course, some hard physical limits to the resolution of film, but most film is not used anywhere near those limits.  Further, because film--unlike digital camera sensors--contains a somewhat random arrangement of light-sensitive molecules, it does not exhibit the aliasing problems that can sometimes digital cameras.  If a digital camera is focused on a wall which is placed at a distance so that each pixel represents one inch, and the wall is painted with alternating 0.8" black and white stripes, the picture may (given perfect focus and perfect optics) show alternating four-pixel wide stripes of 60% gray and 40% gray.  Such phenomena are not a factor when using film, since it lacks the regular arrangement of light-sensing molecules.  If a film camera were to take a picture of such a wall, any particular part of the film showing a white stripe would have a higher probability of being dark (assuming negative film) than the areas exposed to dark stripe.


Does the Skirmish class feat substitute Sneak Attack for the purpose of prerequisites?

Question: In several other forums and guides I have read that Skirmish can be used to substitute Sneak Attack for the purpose of prerequisites of feats. However I cannot find anything in the rules about this. Is it true that Skirmish substitutes Sneak Attack in said case and where do the rules state this?
Comment: Can you link to one or more of these guides?
Comment: Indeed, it's hard to prove a negative, and I would like to believe it to be the case that Wizards did make such a statement - can you share the source(s) that led you to this question?
Comment: It appears here and there, it is never founded however. One is found in the Scout Handbook here: http://rpgbot.net/dnd35/characters/classes/scout/ When you go to the feats section, it is stated in the "Craven" feat.
Answer: After looking through Complete Scoundrel, I found something that specifically states that Skirmish does not count as Sneak Attack for feat prerequisites:
Complete Scoundrel p.71/72

Although the skirmish class feature of a scout (Complete Adventurer) doesn't count as sneak attack for the purpose of qualifying for feats, a scout with the Swift Ambusher feat (page 81) can combine sneak attack and skirmish extra damage for the purpose of qualifying for ambush feats. Even with this feat, a scout can't sacrifice skirmish bonus damage to gain the benefit
  of an ambush feat.
Answer: It appears that people (likely including me ⌐.⌐) are unconsciously expanding the rules about sneak attack and sudden strike in Complete Adventurer and Complete Scoundrel to also include skirmish. For reference, those rules:
Complete Adventurer pg. 8

Sudden Strike and Sneak Attack
For the purpose of qualifying for feats, prestige classes, and similar options that require a minimum number of sneak attack extra damage dice, treat the ninja's sudden strike ability as the equivalent of sneak attack.

This sidebar appears in the section on the ninja, about sudden strike. The scout section does not have any corresponding sidebar about skirmish.
Complete Scoundrel repeats this statement in a sidebar on page 25 entitled "Skirmish and Sudden Strike," where these two class features are reprinted since they are used in Complete Scoundrel prestige classes. The skirmish section, however, again does not indicate any such correspondence between skirmish and sneak attack.
Finally, Rules Compendium does not seem to repeat this rule at all, and refers to skirmish only in the section on precision damage, which does not address qualifying for anything, just how precision damage works.
So it looks like people are just unconsciously expanding the rules for sneak attack and sudden strike to include skirmish as well. And I think they are right to do so—skirmish and sudden strike are both inferior forms of precision damage, so it makes sense that options available to sneak attack would also be available to them. Skirmish's damage is extremely low, and it could really use the benefit.
Comment: I see your reasoning and I too would like it to be so, but here's why I think it shouldn't apply. Skirmish and Sudden Strike both appear in CS and CA but only Sudden Strike is connected to Sneak Attack, because - I believe - the trigger conditions are similar apart from flanking. They could have also connected Skirmish, but they didn't. Skirmish is different and much easier to trigger, especially with ranged weapons.
Comment: @TheQ Skirmish is definitely not easier than sneak stack, and really not easier than sudden strike unless *Complete Champion* is also in play (which would have been impossible when published). Precision damage relies on applying it many times in a turn—skirmish cannot do that without some way to move and full-attack in the same turn. And then even if you do, the damage is a lot less. Balance is definitely not a good reason to deny skirmish those options.
Comment: True, I didn't consider full attacks.


An example of autocorrelation in residuals causing misinterpretation

Question: I'm looking for an example of time series data where a regression of y~x has autocorrelation in the residuals that leads to misinterpreting the model. This is for a class demonstration where I would ideally show them the results of an OLS model and the results of a GLS model with an appropriate correlation structure and explain the differences in the coefficients and their standard errors. Any examples out there that folks have used?
Comment: Note that if the disturbances are autocorrelated, the estimates of OLS coefficients are still consistent, only the standard errors are not correct.
Answer: Chapter 5 in this textbook:

Heij, De Boer, Franses, Kloek and Van Dijk (2004)
  Econometric Methods with Applications in Business and Economics.
  Oxford University Press

uses two examples to illustrate how to test and interpret the presence of autocorrelation in the residuals from the classical regression model. Below I summarize the idea of these  examples.
As you mention that it is for a class demonstration, I would recommend you the software gretl. It contains several data sets
from textbooks in Econometrics as well as the necessary tools to reproduce most of the examples on those textbooks. You can check the data sets that are available here. If you have any of these textbooks you will probably find there an example that is suited for your purposes.

The first of the examples mentioned before uses economic time series data (interest and bond rates, available here). The authors explain that the presence of autocorrelation in the residuals of a static regression of changes in the bond rate on changes in Treasury Bill rates suggests that the model is not correctly specified. As it often happens with economic data, some of the dynamics is not captured by a static model. A possible reason is that adjustments to deviations from an equilibrium relationship among the variables may take more than one period. Upon this interpretation, a dynamic model with one lag of the dependent and explanatory variables is fitted and tested against the static model.
The second example uses cross-section data (income and consumption of food in 48 households of comparable size, available here). A model for  expenditure as a linear function of total consumption and average household size is fitted. Then the authors show that Breusch and Godfrey test suggests the presence of autocorrelation. Similarly to the other example, this result is interpreted as a misspecification of the model. In the context of cross-section data adding lags of variables does not make much sense. The authors propose instead a non-linear relationship among the variables, which is fitted through non-linear least squares.
Answer: The following not only answers the OP's question about a data set that requires more than a simple OLS solution BUT also answers more general questions (unasked by the OP) regarding other possible deficiencies of OLS When applied to time series data. I use AUTOBOX here ( a piece of software I have helped develop) but one could use any software that can incorporate user-specified predictors while identifying an appropriatw arima structure and the need for any necessary unspecified dummy variables reflecting unspecified deterministic changes in the data. For a simpler problem set (less complicated solution required) just use the first 68 values.
TIME SERIES DATA
In http://www.autobox.com/stack/yaffe.xlsx we have 134 months of data ( Y first then  X) . The OLS solution is here  with model statistics  . The acf of the residuals suggest model inadequacy   . The actual/fit and forecast graph is here  suggesting clumps of non-zero residuals.  The actual plot of these questionable residuals is here   A comprehensive approach GLS suggests not only suggests the existence/presence of auto-correlative structure but the impact of a level shift, seasonal pulse and some one-time only pulses in addition to a lag/delayed effect of the user-specified  predictor variable X. Here is the GLS model and here  with final model statistics here  . The plot of the acf of the residuals appears to suggest model sufficiency  with residual plot  and a respectable looking actual . fit and forecast graph . Note that a GLS soultion not only deals with off-diagonal effects but possible variance change effects (not seen in this example) AND non-constancy in the expected error term (found in this example by the inclusion of a level shift and a seasonal pulse and a few one-time anomalies. Here is the plot of the acf for the errors from this model  suggsting sufficiency.


Frequency Analysis Character Distribution Data

Question: Is there a location I can download character distributions for frequency analysis used in decryption attempt validation? I am specifically interested in ASCII value [32, 126] frequency distribution for plain English language text. This would imply case-sensitivity and include punctuation. I'm not concerned with data formats.
Comment: You might have to take some larger body (the standard term is 'corpus', such as [BYU's Corpus of Contemporary American English](http://corpus.byu.edu/coca/) and reduce it yourself.  Most focus on words & phrases, so might not have all of the punctuation and such that you're asking for.
Answer: Second try: Google Ngram Viewer contains raw counts of 1-, 2-, ...-grams of text, retrieved from its book scanning endeavor. The section 1-grams contains counts of the occurence of lettres, numbers and even punctuation. They are provided as tab-separated value files, so the frequencies should be derivable with modest scripting efforts.
Found via Wikipedia article Text corpus.
Answer: What about the (frequency analysis) article's first link to Letter frequency (Wikipedia)? It lists letter distribution for English and other languages, all properly sourced:
<code>Letter   Relfreq
----------------
e        12.702%
t         9.056%
a         8.167%
o         7.507%
i         6.966%
n         6.749%
s         6.327%
...
</code>
Comment: @FreshPrinceOfSO these table only deal with a case-insensitive alphabet, while the question asks for ASCII frequencies, so at least lower-/uppercase letters, numbers and punctuation should be included. This is what I tried to address in my second answer.
Comment: I was looking for all ASCII values [0,127] or at least printable ASCII values [32,126].
Comment: @awashburn Why can't you manually convert them?


Making sure only one of electric shower or instantaneous hot water heater can operate at once

Question: I'm completing the renovation of an annex. The annex shares the mains supply with the main house which has a single phase connection rated as max 90A. I'd like to fit an electric shower (9.8kW) and an instantaneous electric water heater (9.5kW) into the annex; giving a combined draw of ~80A. Clearly using any other power hungry device in either the annex or main house (eg kettle, oven etc) would then take me over 90A. I thought that a possible solution is to only allow the instantaneous water heater to draw power if the shower isn't operating. Is anyone aware of any product which would cut power to the water heater if the shower is in use so that the max draw would be reduced or any other cunning solution (other than ripping out the shower and water heater)
Comment: A relay can do what you want.
Comment: @SolarMike thanks a relay would work, but I'm not sure what would power the coil of the relay. Any thoughts?
Answer: Why do you need two?
In Europe, some showers have their own, on-board, built-in on-demand water heater just for the shower. This is called an "electric shower".
Which begs the question of why you need two on-demand water heaters, since you are already installing one for the whole house.  Simply using the one would solve the power problem.
Or, if your issue is that the shower and kitchen are distant from each other, and you don't want the long delay, then OK, we have to hunker down and have two heaters, and must solve the electrical problem.  But then, again, why a heater dedicated to the shower?  Why not a whole-bathroom heater so you can serve the sink also?
A relay would need to be current-activated
There's an easy electronics approach with a gadget called a reed relay, which placed next to a high current wire will engage.  It needs 10 ampere-turns to operate, typically, and you'd have ~40A going through that wire, so merely orienting the reed relay correctly should get the job done. Essentially, drawing current on the shower heater would throw the relay and knock out the other heater (I presume you'd want it that way).
However, the challenge here is doing this with mains-rated equipment acceptable to your jurisdiction. It's not as simple as "raid the electronics parts bin" since the equipment must be mains rated.
Comment: @JPhi1618 that's definitely how I would do it, but low-voltage isn't a common thing in Europe, so there isn't the handy HVAC/doorbell parts bin to raid.
Comment: from electrical equipment suppliers (but they they mainly seem to have current sensing relays).  also, current operated relays are used in some motor starting circuits, but I'm not sure where to buy those ones.   also combining an AC potential (voltage operated) relay with a current transformer could make a current relay.
Comment: The reed relay could operate the coil of a mains rated relay using low voltage.  So you could raid the parts bin and be compliant a little easier.
Comment: thanks both for the advice. I think a reed switch operating a mains relay sounds like a suitable solution.
Comment: current relays are are available off the shelf.
Comment: @Jasen do you mean, from electronics suppliers with the RU component rating? Or electrical equipment suppliers with the UL equipment listing?
Comment: [This](https://www.grainger.com/product/DAYTON-Current-Sensing-Relay-1EJF6) would be an example, but would need to be used with an external CT as it only provides a 0-5A range. [This](https://www.se.com/ww/en/product/A9C15908/cds---single-phase-load-shedding-contactor---2-channels/?range=836-acti9-cds) would be an integrated option with timing and everything.
Answer: What you need is a shower priority unit
Various types are available for two or three showers, with or without ladder or first-come-first-served priority. Made by Garo and available from larger electrical merchants in the UK and Ireland.
Comment: Wow, great product. Say, could you buy some of those for us Yanks... Like about a million? They'd be just the ticket for countless EVSE installations..
Answer: Current-activated relays are available from industrial automation houses.  They can be purchased with variable or fixed operating current setpoints (the current at which the relay contacts close). It is unlikely that you can find one that is capable of switching the full current of your load, so you will need a current activated relay controlling a single phase contactor that is rated for your full load.
You will need to find a current activated relay that has a DPST or DPDT relay at its output, because you will be wiring your contactor to the NC (normally closed) contacts of the relay.  This will allow your water heater to run when there is no current flowing to your shower heater, and will disconnect your water heater when there is current flowing to your shower.
The current controlled relay, contactor, and 24VAC transformer (if necessary) will need to be mounted in an approved box.  Do you know however, that if you are shower heater cycles on and off rapidly for whatever reason, this will cause the whole system to cycle rapidly, which may reduce the life of your other water heater.
I'm happy to add a schematic if you want to pursue this route.
Comment: I'm happy with circuit, the only difficulty is finding components that are designed for the current I'm dealing with at a sensible price - but I'm sure I'll get there.
Answer: A very simple manual solution is a dual-throw switch. These are often disguised under names like 3-way switch, interlock, generator transfer switch, selector switch, or changeover switch. The common terminal would be connected to the power source; the electric shower and the electric water heater would each connect to one of the switched terminals. A person could then select either of the two loads by throwing the switch. The solution could be embellished slightly by using a pair of relays to control the mains power. The relays could be chosen with mains-voltage coils or low voltage coils. In the latter case one might choose a 5 volt DC coil and power it with a USB charger adapter.
An automated solution could be built around relays with the addition of some control circuit. This could be as simple as a one-shot timer: push a button to select the electric shower; it remains energized for some fixed number of minutes and then power is automatically switched back to the electric water heater. Or the automatic control could be made more complex. For example both relays could normally be closed until a load is sensed (with a current transformer, a reed switch, a Hall effect sensor, etc) and the "other" relay could be switched off while the load remains active.
Comment: Yeah, a 3-way switch would suffice, since this is probably Euro single-phase, but at 40A flow the wires must be enormous and so must be the switch - more like, contactor!  Of course if it's 2-phase or 3-phase then the 3-way gets a whole lot more complicated.
Answer: There are many manufacturers for these power switches, named priority/interlock/selector switch, shower change over switch, load shedding switch, Lastabwurfrelais etc.,  e.g. Garo, Eaton, ABB, Siemens, Eberle, Doepke, Hager.
Searching might be a problem because of these many names.
Another aspect is saving money and energy: A dedicated shower heater (tankless or with tank) can be combined with a counterflow heat exchanger. That way a huge amount of energy and money can be saved, some 25 to 45 % in practice. Some of the mentioned devices do only cut the low priority device if a certain (adjustable) current is measured, so some parallel use might be possible .
The electronic tank less heaters must be suited for the higher inlet water temperatures coming from the heat exchanger (20-30 degree Celsius), which might be restricted since the power electric elements like triacs or IGBTs are cooled by the incoming water.
There are many DIY instructions for simple inexpensive easy-to-build shower heat exchangers, f.e.
https://m.youtube.com/watch?v=ZKrPT0_vSug
The use of a central electric water heater in combination with local water heaters can help to optimize the integration of modern systems like heat pumps, which rely on small temperature differences in order to get a  high cooefficient of performance COP.
This water may be warm enough for dish washing or hand washing, but for the shower an "afterburner" can be used.
So the use of heat exchangers with local electric water heaters is highly recommended - if not to say it should be mandatory.
Comment: thanks for the search terms - very useful. The heater exchanger ideas are food for thought. Thanks again


Should I attach both my bank account statements for Schengen visa?

Question: I am planning to apply for a Tourist Schengen Visa Application (Hungary) from Azerbaijan.
I have a question regarding my bank statement.
I am self-employed, I have a registered software company, my clients are online, they pay me on Webmoney wallet.
Then Webmoney transfers the funds to me on my personal bank account (1).
After that, I transfer my funds and accumulate them to my other bank account (2).
I have Income tax papers and returns, my question is do I need to give both of the accounts statements ?
My bank account (2) is where most of my funds get accumulated and I was planning to show that statement. Would this suffice ?
Answer: Well, You should show both of your account's statements. and describe all this situation in the Cover letter in detail.


MTG Multiplayer—Card Control and Losing the Game

Question: I just need a bit of rules clarification that I'm confused about. If I Donate an enchantment to an opponent in a multiplayer game, and then lose the game myself, does the enchantment leave play with me or does it remain under the control of my opponent until they lose or the game ends?
Answer: When you leave a multiplayer game, all cards and permanents you own, including the ones that other players control, leave the game. Specifically, this means that the enchantment you Donated will leave the game. The relevant rule is 800.4a:

When a player leaves the game, all objects (see rule 109) owned by that player leave the game and any effects which give that player control of any objects or players end. Then, if that player controlled any objects on the stack not represented by cards, those objects cease to exist. Then, if there are any objects still controlled by that player, those objects are exiled.


Globally defined integral curves on the tangent bundle

Question: Let $(M,g)$ be a riemannian manifold and $TM$ its tangent bundle. We know that if, for instance, $M$ is compact, any integral curve of any vector field on $M$ can be defined in the whole $R$ and not just locally. A similar result exists for left invariant vector fields on Lie groups. We know also that if $M$ is complete as a metric space, then it is geodesically complete, i.e. for any $p \in M$ and for any $u \in T_pM$, there exists a geodesic through $p$ in the direction defined by $u$, defined in the whole real axis (geodesics are integral curves of the geodesic spray, which is a vector field of the tangent bundle). I am interested in formulating some suitable assumption for $TM$ that allows to extend each integral curve of $TM$ in the whole real axis ($TM$ is not compact except of some trivial cases). This is because I would like to study global solutions of second order ODEs on riemannian manifolds (which are integral curves of second order vector fields, i.e. vector fields of the tangent bundle) So I need to put a property on the tangent bundle which (almost) directly implies that each integral curve of the tangent bundle can be defined globally. Any idea?
Comment: Is the word bounded perhaps missing from the first paragraph? There are incomplete vectorfieds on R... also any manifold admits a complete metric.
Comment: What do you mean by integral curve of $TM$? We can talk about integral curves of vectorfields and what vectorfield do you have in mind?
Comment: I mean an integral curve of some vector field in the tangent bundle. I have a second order ODE in the manifold $M$ and I am able to write it as a first order ODE in $TM$, so its solution is an integral curve of the vector field in $TM$, that can be represented locally in a way obtained directly by the second order ODE. The problem is that I have no idea how exactly this vector field looks like, so I need an assumption for $TM$, which provides that we can extend each integral curve of each vector field of $TM$ until infinity.
Answer: There is no assumption on $TM$ that will do the trick for all vector fields, as you can embed the example of Poitr Hajlasz into $TM$. However there is the result that any vectorfield that is bounded w.r.t. a complete Riemannian metric will have complete integral curves (I think this is in Hirsch' differential topology book). The metric on $M$ defines one on $TM$ So you can check it w.r.t. to that metric.
Comment: I don't understand how the previous example can be extended for $TM$. Could you write some more details?
Comment: Just writeit out in a chart and extend it by zero using a bumpfunction


Why is iTunes photo sync showing separate event for each photo?

Question: I am syncing photos through iTunes to my iphone but I am seeing 40 events with the same date show in the Events selector. The same photos are included within a single event in iPhoto. How can i get iTunes to see these events as one?
Answer: I have same problem with iphoto latest version 9.4.2. At genius bar nobody know a solution. Genius talked to Cupertino, they know about the problem, we have to wait for an update for iphoto software.  I tried using "iphoto library manager" software (not apple) to recover the iphoto library. Apparently problem was solved in itunes, but iphoto became very slow and i came back to normal iphoto library.
In itunes events have a date as a name and each contains few pics, some of them have been deleted from the iphoto library but still in those strangfe events, maybe as a miniature.
Somebody can help?
Deleting ipod photo cache non solution, unfortunately.


What is a term for someone who always forgets about his favours?

Question: If you ask someone for a little favour, e.g. to close his door whenever he's listening to loud music or television, but this person keeps "forgetting" this, always. What is a term to describe this kind of person?
Comment: My word choice might be a *thoughtless* person.
Comment: When you asked them to do this, did they agree to do it at the time or did they ignore or discount the request from the start?
Comment: They agreed upon doing it whenever they would turn on loud music. But then always forget it afterwards (nomatter how often you keep asking them.)
Comment: I feel that the situation you describe is one thing, and "someone who always forgets about his favours" is something entirely different, at least the way I'd understand that definition. If he's not closing that door, then there simply don't exist any "his favours" to forget, there have been no favours done by anyone. "Forgetting about favours" would mean something like ignoring favours you've done *for them* and not reciprocating; but the situation you're describing is simply "not keeping promises". I.e., there would be *different* answers/terms for the 'body' of your question and the title.
Answer: There are many words that can be used; that person could be forgetful, or that person could be discourteous. It depends on if you want emphasize the cause or the effect.

discourteous
  (adj.)
  showing rudeness and a lack of consideration for other people
absentminded
  (adj.)
  (of a person or a person's behavior or manner) having or showing a habitually forgetful or inattentive disposition

My thesaurus lists these promising synonyms for absentminded:

distracted, preoccupied, inattentive
Comment: Also "inconsiderate", similar to discourteous.
Answer: Maybe it's just me but I read the title and content of this question differently. I agree with @user3169 about "inconsiderate" as an answer to the content, but as for "someone who always forgets about his favours" a word that comes to mind is "ingrate". An ingrate is "an ungrateful person".
Answer: Depending on whether the person was forgetting through malice or absentmindedness, I'd describe them as either inconsiderate, or forgetful/absentminded.


Cocktail shaker - silver plate but black on the inside

Question: I picked up a 1920s, silver-plated cocktail shaker from the op-shop.  It is super fabulous.  However, the inside is all black.  Is it safe to make and serve cocktails from this shaker?  What should I use to clean it??
Thanks  xx  irene
Comment: Could you post the shaker photo onto the question?
Comment: I would also like to see a picture, without one we would only be able to hap-hazardly guess.
Answer: Yes, it's safe.
Silver tarnishes easily, particularly in contact with sulfur-containing foods, particularly egg. The tarnish is not hazardous, and can be cleaned off with silver polish or with DIY chemistry like in Tetsujin's answer. Black tarnish doesn't form readily on its own, so if you're not planning on using eggs in your cocktails then cleaning off the existing tarnish will likely last you a while (it'll be bright silver initially, but will quickly tarnish to a dull greyish silver). However, it can also be ignored (which was apparently the approach taken by the previous owner).
Comment: Thanks!  I appreciate you taking the time to answer my question.  Regards, rene
Answer: Cheap & cheerful trick...

Break your shaker down into its separate components.
Use your washing-up bowl.
Get 30cm or so of aluminium kitchen foil, & get it to sit in the bottom of the bowl. Doesn't matter of you have to crinkle it but don't screw it into a ball.
Drop in your silver.
Add half a packet or so of bicarbonate of soda.
Fill with very hot water - from the kettle, ideally, just off the boil. Deeper than your shaker size Yup, it's going to be hot, be careful. Use gloves & a wooden spatula for manipulation. Give it a good stir.
Push it round for a couple of seconds with the spatula until it stops fizzing.
If it's particularly ornate, you might have to use a toothbrush, but you really shouldn't need to.
Remove clean shaker, discard now black foil.
Repeat if necessary.

It can smell a bit eggy & can taint the bowl, so if you've got a large 'glass' [pyrex etc] heat-resistant bowl that can stand boiling water [be very careful] that may be a better choice , but the washing up bowl can be bleached out if the smell lingers.
Comment: Thank-you, I shall try this once I get home in a few weeks.  I shall try to post some pics of the shaker. (i'm not very tech)  I appreciate you taking the time to respond to my query.  Regards, rene.


Is it possible to skip verification of blockchain data when using bitcoin core?

Question: Because I need bitcoin core client only for JSON-RPC requests. Will I need pruned initialization or normal initialization of bitcoin core client for successfully running such requests? (I guess client software does full verification in both modes, just avoids storing of blocks in former mode.) From what I understand if I prune the block data, It will only store around 2GB of data on my local system. However, I am not sure if I need nth block data using JSON-RPC call, which can be any block from beginning itself, will my pruned client get it from the main chain with the help of its peers? I just wanna save my bandwidth and also wanna use JSON-RPC feature. I am really confused. Any help will be appreciated.
Answer:
I just wanna save my bandwidth

Running a node in pruned mode will not save you bandwidth during the initial block download (sync), you still need to download all blocks and validate them, even if you don't store them longer term (pruning lowers disk space requirements). You can fine-tune your data upload limits in the bitcoin.conf file though.
Most RPC calls will work with a pruned node, some will not though. From a quick search for some examples, see:
https://github.com/bitcoin/bitcoin/blob/v0.11.0/doc/release-notes.md#block-file-pruning
https://github.com/bitcoin/bitcoin/blob/v0.12.0/doc/release-notes.md#wallet-pruning
Comment: Getblock could work by asking other peers, but simply isn't implemented in Bitcoin Core. Getrawtransaction cannot work, as the P2P protocol has no mechanism for querying a single transaction - it'd need to download all blocks over again just to find the transaction you want.
Comment: Links suggests getblock and getrawtransaction won't work in pruned mode. Why would it be like that? Why doesn't it ask its connected peers to share the required block data? It should download the block at the time of getblock command time.


How do I use the Organizational Browser in My Site

Question: I want to have an overview of all users within my organization, including pictures. Pictures and business information is available on the my sites, however an overview is not possible. Probably because there is no organizational sturcture implemented in our Active Directory. How can I get an overview of all users?
Answer: You will either have to implement it in AD, or you can set the manager property for each user profile in SP.
Comment: Okay. How do I set the manager property. I have been searching for it but wasn't able to find it.
Comment: Go to your user profile service application.  Then click on manage user profiles.  Find a profile, and then click the dropdown and edit profile.  Find the manager field, and choose someone in people picker control.  If you have a lot of users (more than say 10 or 20), I would code this in c# or powershell.


What is the purpose of the 20 XRP cost to start a wallet?

Question: Does the money stay in the wallet or is it used to pay for something?
If it's used to pay, who does it go to?
If it stays in the wallet, am I allowed to take it out and drain the wallet later without any consequences?
Answer: Unlike a bitcoin receiving address, a funded Ripple wallet is a real thing on the ledger that has properties. This has advantages and disadvantages, but one of the disadvantages is that there's a cost associated with having one. To cover the costs imposed on the network, the XRP Ledger has a "base reserve" that is XRP that is not spendable or transferrable. You can use the reserve to pay transaction fees and, if the reserve drops, you can transfer out XRP to the new reserve level.
Some of the advantages of this scheme include:
The ability to change the key protecting an account without changing the receiving address.
The ability to configure an account for multisign and change the keys, signers, or quorum, again all without changing the receiving address.
Addresses can configure what assets they're willing to accept as payment and payments to them can automatically route through intermediary assets to find the cheapest path.
Accounts can place offers to trade one asset for another on a distributed exchange that follows deterministic rules.
The reserve goes up (currently by 5 XRP) for every additional object an account owns in the ledger (such as a trust line, offer, or escrow). You can reduce your reserve by eliminating these objects, but current rules do not allow the base reserve to ever be transferred or spent -- it covers the cost associated with recording the fact that the account has already performed certain transactions and without this recording, those transactions could potentially be replayed.
Comment: What dos this statement mean in the post above "The reserve goes up (currently by 5 XRP) for every additional object an account owns in the ledger (such as a trust line, offer, or escrow)" Dos this mean you loose more than 20 Ripple when sending somewhere ? It is not clear what a additional object is / trust line ? Thankyou if you are able to clarify
Comment: You never really lose anything, It's just XRP that can't be transferred, though it can be used to pay transaction fees. So if you have three offers on the books, your reserve would be 35 XRP, and if you had 50 XRP, you could only transfer or trade 15 XRP.
Answer: In order to activate the wallet, you need to send 20 XRP to it. You don't lose this money in any way, it's yours to use after you get 20 XRP. Note that you can send 20 XRP over multiple transactions, but you're wallet will show a balance of 0 XRP until all transactions are confirmed. Then the true balance of the wallet will show up.
You can go below 20 XRP anytime, but your wallet will become temporarily disabled. This means you cannot send any more transactions from that wallet. You would need to send it more XRP to reactivate it.
This is analogous to a bank account with a minimum deposit. This documentation goes more in-depth about the purpose of the threshold.
Comment: You can send transactions from a wallet whose balance is below its reserve. You just can't spend or transfer out XRP.


Gaussian Mixture Model of Solar Data(Power in kW)

Question: Gaussian Mixture Model in Matlab( More likely that it will be a combination of 2 normal distribution or Beta distribution)
Let's say I have a collection of data that I want to model using Probability distributions. I'll call my data "yearly_data" and a frequency distribution is attached below and as it can be seen, it has 2 peaks therefore it cannot be modelled using a single Gaussian so it has to be a Gaussian mixture model. I want to be able to fit and produce a PDF of the model. How can I do this? I am more interested in how this is done in Matlab so if you can't help with Matlab then don't answer the question. Explanation of theory behind it will also be useful. Please provide a sample code
Answer: You can try this
https://de.mathworks.com/help/stats/gmdistribution-class.html?requestedDomain=www.mathworks.com
and this explanation
https://youtu.be/Rkl30Fr2S38


Do published Android apps pay for open source libraries they are using?

Question: If an android app is using an external library for instance like (Retrofit, EventBus, or GSON), does it have to pay for its service once that same app is published in the Google Play Store (Goes live)?
Answer: This would depend on the licence terms of each individual library. For Retrofit for example, I quickly found this: https://github.com/square/retrofit/blob/master/LICENSE.txt which is the Apache licence. It imposes conditions on how you use it, but it doesn't mention that you have to pay the contributors. Other packages may be different - you need to look at each one separately.
Comment: Looks like each library will have a license.txt file that contains permissions on how much of allowance you have in that library usage as far as commercial usage and other right.


Using iPhone as iPod touch

Question: I am trying to use an old iPhone 3GS as an iPod touch.  I left in the old sim card and connected it to iTunes but it will not activate.
Comment: What happens after you connect the phone to iTunes? Is there an error message? Do you start any commands through iTunes?
Answer: This should work, but might not be ideal - get a pay-as-you-go (i.e., non-contract) SIM with a small amount of credit on it (I suppose not everyone has them lying around) and activate it with that (it needs to be on the same network that the phone is locked to) and then disable all the 'phone' functions. It should then function just fine.
Comment: I don't think this will help the original poster if he isn't from the UK...
Comment: Same applies for other countries, just different currencies :)
Answer: Per Apple's support documentation you'll need to activate the device using a SIM from another activated iPhone to activate the device. If you don't have access to another SIM card you could consider taking the device to an Apple store, or a mobile vendor that carries iPhones. If you don't have access to either of those, as a last resort you could download Redsn0w and activate the device without a SIM. The last method is not supported by Apple, but will accomplish your task.
Comment: So you can't activate an iPhone with just any SIM card?
Comment: I'm not able to test this, and Apple doesn't list that as an option. If someone knows otherwise, please comment or edit my answer.
Answer: If you remove the cellular service attached to a Sim card in an iPhone, it will continue to work Foley with only one small exception:

phone calls, SMS and cellular data will clearly be off so you can't use any of those functions
You will want to leave the Sim card inside since it is part of the self activation if you restore the iOS.  At that point the phone will receive Bluetooth and Wi-Fi and work like it was in airplane mode and you turned those two radios on solely.

The cellular radio will still be active for emergency 911 calls, and you will want to turn off the radios in areas of low coverage because the device will be using a lot of energy to transmit and keep in touch with distance out hours just as if you had maintained service.

Using iPhone as iPod touch


iMessage log in Problem

Question: This is the error I am getting at the moment when I try to log into iMessage. The same error occured when using FaceTime. I can use my appleID for the Appstore.
Do you know what I can do about this?
Comment: It could be that Apple's servers are bogged down because of the WWDC and release of new OS's to developers. I'm not seeing any system outages, though. I would try again later. https://www.apple.com/support/systemstatus/
Answer: This is a commmon problem with Hackintosh'ed computers. Is the computer you are using with OSX genuine?
Wether it is a real Mac device or not, the steps to fix this should be very similar. Here is a very long thread describing each step to fix this in great detail.
To start off, I would make sure that your Apple ID is verified. You can check the 'Verified' status of your AppleID by logging into AppleID's online management.
Comment: thank you for the reply. The Hardware is real mac and the software as well, as far as I know. I have turned off system integrety protection as the only modification to the normal OS X. Where can I find the verified status? I logged in but cant find it.

iMessage log in Problem


setting external monitor blind. laptopscreen broke

Question: my laptop screen is fully broken cracked all over so i cant see anything at all but i believe the computer still thinks the screen works so when i plug in an external monitor nothing happens because i cant go to the control panel and work the necessary settings. any advice im working standard old version of vista, cheers.
Answer: use Fn in combination with the corresponding function key to toggle displays.
Answer: A lot of systems will send the laptop screen to the external screen automatically when you shut the laptop screen.
Attach external keyboard and/or mouse and see if this will work for you.
Answer: Turn the computer on with the external monitor plugged in. It should automatically use it.
If that doesn't work, check your keyboard, it might have a function key that allows toggling between the internal and externel displays. What laptop is it?
Answer: We're really going to need to know the laptop model if booting the laptop with the external monitor attached does not work.
(I should also point out, that some external monitors do not show all of the bootup screens. You may not see BIOS screens or even the Vista loading screens. You may not see an image up to the login screen.)
On my Lenovo Thinkpad, the Fn key combination is Fn+F7


Why doesn't Stack Exchange support 2-factor authentication (2FA)?

Question: Why doesn't Stack Exchange support 2-factor authentication (2FA)? If I put this in as a feature-request, will the powers that be consider it?
Comment: @RobertHarvey No. It's useful on an account-by-account basis. If any given person is worried about someone else guessing/obtaining their password, they could enable 2FA for their account to reduce that risk. For example, staff/moderators might be worried about someone breaking into their accounts and going on a privilege-misuse spree. 2FA on their accounts would prevent that, without requiring every normal user to have it.
Comment: It's 2019, can this be revisited? The accepted answer isn't a true solution for the reasons mentioned in the comments.
Comment: It is very embarrassing that SO doesn't support 2FA. I would even expect it to fully support MFA!
Comment: I agree with the comments above. It is very strange that a programming-focussed website does not provides a 2-factor authentication log-in method. I am confident that many programming-minded people on StackOverflow will start using 2FA when available (or promoted).

Moreover, as this post has been closed about 6(!) years ago, it would be great for StackOverflow to reconsider the request for 2FA.

Besides my remarks, I also have a question - how much 'interest' (or upvotes) should this post have in order to make it worthwile for StackOverflow to consider 2FA again?
Comment: In a world increasingly full of breaches and cyber security concerns, I'm at a loss for why Stack Overflow, a *programming-focused* Q&A site, doesn't concern itself enough with said security to implement a 2FA solution that doesn't rely on some 3rd party account linking. It outright looks bad in 2021 IMO, and is less and less excusable as the feature increasingly becomes standard fare on every other major platform out there. It's time for this to be formally revisited.
Comment: A hacked email and a password reset - then your account is lost even when you have 2FA on the other logins.

We have U2F nowadays - at least we should have TOTP 2FA on stackexchange.
Please take it up again - thanks
Comment: The purpose of two-factor authentication is to verify that you are who you say you are to the system.  Wouldn't you have to force everyone to use it for it to have any value?
Answer: The alternative to Martijn Pieters' answer has just been mentioned on uber-meta:

So, over the last couple of weeks, I built a bare-bones two-factor authentication system for Stack Exchange OpenID.
...
Before we ship this feature, we probably want to finish at least the site login/integration and SMS stuff. [...] Your input will help us determine whether to continue with the project or shelve it.

So if you want to use Stack Exchange OpenID and would like to have two-factor authentication for that, you should head over there and let folks know.
Comment: I don't think 2FA is something you implement only if there is sufficient interest. You implement it if there there are significant security vulnerabilities to be addressed by implementing it. I believe there are, in this age of stolen identity databases and guessable passwords. It's the responsible thing to do, IME. And using a third party isn't sufficient on its own, since many folks don't like to tie accounts together on disparate services.
Comment: There wasn't enough interest in the project to continue with it, so it's been shelved. Sorry to everyone who was in support of it. :-(
Comment: As of late May 2015, the linked page has been edited to add **We've decided that we won't be working on this project. Sorry to all the people who were in favour of it.** at the top.
Comment: I also agree that it's a matter of responsibility with one's users, not a matter of popularity. FIDO may never become popular as it requires buying a hardware device. Still, it's the current best solution for authentication. Using OpenID isn't an alternative, as one of FIDO's features is precisely privacy, so that our accounts on multiple services aren't tied together. IMHO one of the reasons OpenID is bad is because its base functionality relies on the main company knowing all the services and portals we're using it to login.
Answer: Stack Exchange supports GitHub, Google and Facebook logins, all three of which support 2-factor authentication.
Just use one of those for your login and enable 2FA there.
The Stack Exchange 'native' login does not support 2FA at this time.
Comment: I'm downvoting this exactly for the reasons `theory` gave under the other answer: "And using a third party isn't sufficient on its own, since many folks don't like to tie accounts together on disparate services."
Comment: That's good. I suppose it's quite popular, although I don't use it. I wish they'd add 2FA to "email logins".
Comment: I'm downvoting this because I don't use Facebook or Google due to privacy concerns, and prefer keeping all logins isolated.
Comment: -1 because if you distrust both Google and Facebook you are left with inferior account security which is pretty embarrassing for a site network with this scope and focus.
Comment: @OliverWeichhold: sorry you feel that way, but those are the only options you can use *right now*. I note you do appear to trust GitHub, which is one of the supported options.
Comment: @BhaveshDiwan: that's fine, but for people that do want to use such accounts it provides a solution *now*, rather than having to wait for Stack Exchange to revert their decision (in May 2015) not to work on this feature.
Comment: Am I correct in understanding that the recommendation is to delete the email login and require only Google or GitHub login? There are some challenges with logging in to add additional accounts this way, if you separate those accounts in different browser profiles. I personally think it's very odd that Stack Exchange "outsources" its login security to other platforms.


Connecting RDBMS using Embark

Question: Can someone please explain,  How can we configure SQL database for e.g. MySQL using Embark framework and How do we configure this in application.
Comment: It seems to me that this question may be a bit off-topic. Have you asked the question in Embark gitter? The questions on this stackexchange should be more focused specifically on Ethereum. I know Embark is Ethereum related, but the question is really about Embark, not Ethereum. Welcome, though, I see this is your first question.
Comment: @amit-kumar-kashyap please explain more your use case
Comment: Thanks. We want to make some financial transactions which we can store in the blockchain and can be verified later whenever required. Since blockchain is not suitable to store huge data and we also want to store all meta information of the transactions for e.g user name, address, phone number, bank account details other transaction details in SQL so that we can query and search by any keyword in the meta information.
Answer: There is nothing connecting Embark dapps to any type of database. Your best bet would be to treat connecting to a database as a separate application.

Connecting RDBMS using Embark


Rearrangement considerations in feasibility of SN1 in given reactants

Question: I have been asked to compare the feasibility of Unimolecular Nucleophilic Substitution ($\mathrm{S_N1}$) in the following question.

I have received instruction that the reaction will be feasible only in the first compound (which results in a 3° stable carbocation) since 1-chloro-1-methylcyclopropane is angle strained and the resulting carbocation in this case will be unstable.
However, if we consider the possibility of hydride rearrangement in the second molecule, after formation of the carbocation, the following rearrangement should stabilise the carbocation formed, through the delocalisation of sigma electron pair as is seen in the case of cyclopropyl methyl carbocations.

Where exactly am I going wrong?
Comment: Related: https://chemistry.stackexchange.com/q/19090
Answer: The proposed rearrangement would produce a primary carbocation which, relatively lacking in hyperconjugation, is itself unstable.  The proposed rearrangement therefore is not really plausible.
The "instruction" that the highly strained 1-methyl-cyclopropyl cation cannot be formed may be wrong anyway.  This paper reports a substituted cyclopropyl cation as an intermediate in a reaction between a more complex chlorocyclopropane and an alcohol.


V-brake arms too far apart

Question:
I ordered a bicycle, it came with a front wheel detached. I took the v-brake noodle out to loosen the v-brake arms to let the wheel through. However, I cannot get the v-brakes aligned properly. The right arm is waay too much away from the rim. Even if I move the arm with my hand, it doesn't touch the rim (so it doesn't seem like it's just a matter of cable tension. Is there some way to move the arm closer?
Comment: By the way, just in case it's not obvious: The fork should be rotated 180° so that the brake is facing forwards.
Comment: Since brakes are safety relevant parts please ask somebody who is competent with bike to assist you.
Comment: Can you get a picture with it pushed in by hand as far as it will go? Have a good look for what's stopping the movement, especially around the return spring.  It should be easy to push the arm in far enough by hand
Comment: As @Carel notes, new bikes shipped in cartons need some final assembly/adjustments that are safety relevant. Brakes, handlebar/fork/stem and even seatpost need some knowledge. Best is to have someone who knows what they are doing take a look, but even a "how to finish assembling a shipped bike" video on youtube would be a big help.
Comment: Thanks! I was told that elsewhere too, I am not used to assembling a bike so it wasn't obvious for me but I fixed it now.
Answer: I can see one metal spacer between the rubber part of the pad and the brake arm.
V-brake pads use a set of spherical washers which sit on each side of the arm to allow the pad angle to be adjusted.
The typical correctly-assembled order would look like:

pad
spacer
concave washer (flat towards pad)
convex washer (bump side sits in the "bowl" of the concave washer, flat side against brake arm)
brake arm
convex washer (flat side against brake arm)
concave washer (bowl side against bump)
thin washer
nut

Some pads use two different thicknesses of concave washer, so you'd skip 2 and use the thicker washer at 3. See step 2 of these instructions: https://si.shimano.com/pdfs/si/SI-8JF0A-002-ENG.pdf
Comment: I can see both a concave and a convex washer between the pad and the brake arm. poorly aligned, but present.
Answer: There seems to be several issues:

Firstly, the pad position on the right arm looks a bit off. Release the pad nut, and adjust the pad to be perpendicular to the rim while pushing the arm with your hand against the spring so that the arm is close to the rim. Then, while continuing to push the arm, tighten the pad nut. Repeat with left pad if it's off too.
Secondly, the cable seems loose. Rotate the barrel adjuster counterclockwise (usually at the lever) a bit. Put the noodle in the left arm, and compress both arms with your hand so they touch the rim. Tighten the cable using the cable anchor bolt. You should now have a brake that continuously touches the rims. Not very useful as it drags with no clearance.
Thirdly, adjust the barrel adjuster. Rotate it a bit clockwise to release tension. This creates clearance at the brakes.
Comment: That's why I've asked for a photo with it pressed in by hand.  To me the wording doesn't suggest a misaligned pad is stopping the arm
Comment: The cable isn't even connected at the moment.  The OP seems to be saying the arm can't get close enough whatever they do
Comment: Yep, and I suppose the pad position is the cause of the arm not being able to be close to the rim. However, for a working brake the cable needs to be attached too.
Comment: -1 for not mentioning the incorrectly assembled fork. Despite being noted by others in the comments the answer is ambiguous between left and right without mentioning the correct fork set up. While the technique of adjusting the cable at the pinch bolt with a loose barrel adjuster and pads touching rims is a good one, there the answer errs in that it doesn't take into account the obvious inexperience of the OP, and to achieve good results doing this, the barrel adjuster needs to be damn near all the way out, not just "a bit" ccw at the beginning & omits the 1-2mm pad-rim gap as the goal.

V-brake arms too far apart


Atmospheric Conditions leading to different colorations

Question: What kind of atmosphere would a planet need to alter the color of the sun and moon? I know this is rather broad, but I know that a certain gas in our atmosphere colors the sky blue, and gives the sun a yellow tint.
So, what kind of gases, and how much of them, would be required to alter the coloration of the sun to red?
Answer: This is actually a common event right here on earth. You don't need to alter the actual chemistry of your atmosphere for this, you just need to have lots of particulates in the atmosphere. On earth this is usually caused by smoke from wildfires or volcanoes, or by dust storms.
If there's a reason you can't rely on particulates for this, then you'd need to have an atmosphere consisting of significantly heavier elements than ours does, which by extension would require MUCH higher pressures and temperatures, so if this is a planet that humans are supposed to be able to live and breathe on without safety equipment, I'm not sure that'll work for you.
Comment: That's very helpful. I was hoping there might be an alternative way, rather than relying on particles. In the world itself, a person from our Earth is able to be twice as strong, and weigh half as much as a person from that world.
Comment: Do persons from our Earth need to be able to breathe this atmosphere?
Comment: Yes. The main character is of our world.
Comment: Ok, then particulates are REALLY the only viable option. Anything else that would create the 'red sun' light scatter you're describing would render the atmosphere extremely hostile to your protagonist.
Answer: in researching a similar question for my own stories, I found argon has the coloration I was looking for, while still being a common enough element in our own atmosphere to facilitate human habitation. it isn't really the atmosphere that has the color anyway. Like the depth of the ocean and the algae living there on you get green water Ie. much of the Atlantic ocean, and blue water, much of the pacific ocean, though there are exceptions to the rule. it's really the depth of the ocean(s) that give the color attributes the farther down the floor of the ocean is, the darker the color of the water over it. So to is the atmosphere. the air is clear, what we attribute as color is actually the light refraction of deep space through our atmosphere. this can be seen on the surface depending on the altitude of the land mass. those at or below sea level have more intense colors of sky whereas higher altitudes have paler colored skies. Hope this helps.
Comment: If I may, what kind of coloration were you looking for?
But, I do find this helpful. Is there anything that could really create what I'm looking for without compromising the setting too much? There are many deep forests, high mounts, and expansive hills in this world, a condensed Europe if you will.
Comment: my color will be light lavender to the deepest violet at twilight. I chose argon because it was already in our atmosphere. Krypton, and yes there is such a gas, is almost pure white, while neon is red, https://en.wikipedia.org/wiki/File:Atmosphere_gas_proportions.svg here's a list. also, I figured a little extra shouldn't effect human too much, if I don't alter the other ratios of gasses too much. I just looked up atmosphere then follow the trail from there. I knew I wanted a purple sky though! :-) sadly I wasn't the first to have the idea though
Comment: Almost all ideas are already taken, it's the author's job to make it their own. Thanks for the help, I think I'll play a little bit with the atmosphere. Do you know what might happen if there is high Neon levels in the atmosphere and high energy is pushed through the air... say, like lightning?
Comment: I'm sorry I couldn't say. I'm not a scientist :-)
Comment: That's cool. I just learned today that it could possibly create an Aurora. If an Aurora is just energized neon I believe.


Can She-Hulk's hair be cut?

Question: Marvel Comics writer Fred Van Lente just asked via Twitter if She-Hulk has ever had short hair. This got me to wondering if the indestructible She-Hulk's hair can even be cut. Can her hair be cut? And if it can be cut, has an artist ever depicted her as having short hair in the main Marvel Universe (or any other parallel universe)?
Comment: @OghmaOsiris Don't forget to include pictures of Superman's mid-90s mullet in the question. Yikes!
Comment: I'm totally stealing this to write a question about Superman... lol
Answer: As far as I know, neither the Hulk nor She-Hulk are indestructible. They're simply very, very tough. She-Hulk #57 shows that she received a blood transfusion directly from the Hulk. This suggests that a tough enough needle can pierce the Hulk's skin.

Similarly, one might imagine that their hair is tough but not indestructible. And as to the original question, I was able to find images of alternate Shulkies with short hair.
According to pictures on the Marvel Wiki, the She-Hulk from Earth-12 has short hair.

So does the She-Hulk from Earth-23884.

And to address one of the comments, her hairdo as Jennifer Walters appears to be independent of her hairdo as She-Hulk. So cutting her hair in her non-Hulk form wouldn't shorten her She-Hulk hair.
Comment: But Rickey! I wanna play in the club tonight!
Comment: It would probably be easier for She-Hulk to cut her hair when in Jennifer Walters form.
Comment: The picture you are referencing was not a direct transformation image. It was just a splash page so it would not be an adequate representation of the issue. The artist was simply comparing the two to show the variance of size between the two.
Comment: I'd assume the needle that was used on the Hulk is adamantium.
Comment: One of these links is broken, and the images don't have an issue attached.
Answer: Hulk Hair
Why this is a more difficult problem than you think
The problem with the premise of the Hulk and hair starts with the question of how he becomes the Hulk in the first place. Our hair is actually not very tough or very durable, relatively speaking. It is made of a delicate substance similar to our fingernails, hair and skin called keratin. Keretin is little more than a decorative element on the human body and is vulnerable to the environment. Hair is brittle, fragile and easily destroyed. Not so for the enhanced bodies of the Hulk or She-Hulk. For purposes of this article it is assumed I am talking about the Hulk but most of what I will outline for him, will apply to her as well.
Since it is not explained (scientifically speaking) the nature of the Hulk's incredible resistance to damage, we are forced to suppose he has several potential avenues to explain his durability. These are my theories, not the Marvel Universe's (which makes no true explanation of his powers despite what you see in the Marvel Handbook.)
a) His molecular structure, while similar to ours is some sort of organic analogue comprised of a similar substance to our own bodies, but it allows him to be denser, stronger and more resistant to injury. This means all of his cells are stronger and more resilient because at the atomic and molecular level, they are denser structures which comprise his tissues.
This density however, does not seem to extend to his non-altered form, so we have to assume the trigger mechanism and energy source is the part that remains unexplained. (Using the rules of the Marvel Universe, he would have to be like many of their mutants, tapping an alternative dimensional energy source to power his transformation into the Hulk, but it has never been discussed as such. This would be similar to Havoc, Cyclops, Sunfire, or Banshee, whose bodies could not possibly contain the fantastic energies they project as blasts of force, radiation, radiant energy or sonic energy.)
The Hulk's molecular and cellular structures must still resemble skin and hair but would be more like chitin (the material that makes up the protective exoskeletons of insects). While that would make the hulk far more durable than a normal human, it would also make him less flexible, since on humans, thick keratin can be found in fingernails and should be noticeable if the Hulk's skin appeared to suddenly resemble fingernail materials. Whatever he is, he is far more flexible than chitin or keratin is. So he must gain molecular density without sacrificing flexibility or a sense of tactile awareness.
b) A supplement to the superdense molecular structure option could be that the Hulk's body behaves more like a form of energized memory material. Since his powers always radiate gamma radiation, it could be possible his physical atoms are expanded by that radiation pulse. Like a memory plastic, he would expand in size and resistance to injury would increase as the structures comprising his cells would take on a more rigid and damage resistant form. This would explain the Hulk's nearly limitless power, since he would be a localized version of Cyclops' or Havoc's power of extra-dimensional energy, bound within the Hulk's body. This would also mean he releases that energy unconsciously, and at its most powerfully in his enraged state.
It does not explain where his extra mass comes from, but theoretically, if he is creating radiation from an unknown source, he could also be converting that same radiation into mass, since matter is merely localized energy. This would explain his muscularity, and similarity in appearance to his or her baseline form, since the expansion would only add to what was already there. This expansion and toughening would also explain why their haircuts would remain similar and how their hair survives attacks like flamethrowers or explosions. Its molecular toughness would be significantly increased.
c) The last component would be their regenerative process. This process would be related to the massive cellular density, the energized molecular plastic nature of his bones and musculature and linked to his energy source, and matter-creation properties, he would have an incredibly fast rate of regeneration, as his body's plastic nature would seek to restore the original template as quickly as possible. If his energy rate were high enough, it would appear to most onlookers that he did not actually take damage. Only attacks that could dampen his internal energy would have any long term chance of harming him.
This would also explain why in his lesser forms, such as Mr. Fixit, the Hulk was seen to be able to bleed since that form did not seem to have the high levels of energy available to the green or enraged Hulk thus reducing the energy to mass conversion needed to maintain his Hulk state.
The original energy required to perform this transformation is still unknown, but it is unlikely that the gamma radiation explosion Banner was exposed to did little more than activate a latent process or potential already within his DNA and able to be transferred to the She-Hulk through a blood transfusion, since, she as a relative, must have also possessed a similar potential for energy to mass conversion, superdense molecularization of her bodily tissues and bodily functions. The transformations into the Hulk or She-Hulk must still make their bodies only more effective and efficient versions of our own bodies, since they still have to eat, breathe and it is assumed, excrete.
She-hulk does not seem to have the enraged state but her cellular structure seems more stable and does not seem to require a downgrade to recharge. She has been known to remain in her Hulk state, even when unconscious.
In fights, neither Hulk is ever seen without hair even during intense battles using flamethrowers, explosives or even with powerful enemies such as the Harpy, Iron Man or even cosmic beings such as the Silver Surfer or Warlock. This means their hair has the same superhuman resistance due to its molecular structure, but is far more durable than our same keratin based hair would be in the face of similar threats.
As to haircuts, I imagine, the baseline body is the template, so any haircuts or hair styles would transfer to the superhuman form. Likely, any damage sustained unless a connection to their power source prevented it's regeneration would be immediate and instantaneous.
Disclaimer: As this document is written with my own opinions and is not affiliated with Marvel Comics, the ideas therein are mine and mine alone. I am certain Marvel will not put this much energy into deciding why the Hulk never needs a haircut or for that matter whether his hair is ever effected by anything. The same way those purple pants are never atomized when attacked by anything.
Answer: Her hair isn't indestructible, it's simply a lot harder than normal hair.
The implication (regarding haircuts) is that she just goes through an awful lot of pairs of scissors.
She-Hulk: Ceremony v1 #1
Comment: IIRC this story element is what made Byrne leave the book. http://goodcomics.comicbookresources.com/2013/08/16/comic-book-legends-revealed-432/2/
Comment: @VBartilucci - He seemed to have real problems with the character. The "skipping" episode was an especially low moment.
Comment: The "Skipping" episode was a callback to a joke in the lettercol several issues before. There's a general consensus that it was a quick way to kill four pages.

John's done gags like that before. See also the Assistant Editor's Month issue of Alpha Flight featuring a fight between Snowbird and a snow-demon in a blizzard.  Several pages of bare white panels with nothing but word ballons and sound effects.
Comment: @VBartilucci - Here's a Wayback Machine version of your link. Interesting story. https://web.archive.org/web/20160502231656/http://goodcomics.comicbookresources.com/2013/08/16/comic-book-legends-revealed-432/2/
Comment: Current link to the page from @VBartilucci's comment: https://www.cbr.com/comic-book-legends-revealed-432/

Can She-Hulk's hair be cut?


Alpha clipping mask for a PNG file in Illustrator?

Question: So let's call my PNG image layer Z. I have group A of layers that is behind my layer Z and group B of layers that in front of my layer Z. Now, I want to create a clipping mask to apply it to group A of layers using layer Z silhoutte, how can I do that? In Photoshop it's very easy, you simply click with left button of mouse while holding CTRL on a PNG file with alpha channel and it automatically selects the silhoutte of the image, and then you can use that selection on another layer. But how can you do the same thing in Illustrator?
Answer: Illustrator is a Vector program.
You will need to have a path in the shape you desire and then you can use that as the clipping path bounds.

I would recommend either manually tracing it, or if it's a good quality silhouette you could get away with autotrace in Illustrator.
Answer: In Illustrator, you can use the opacity of a raster image as a mask.
In my example, ill use stars as the group of vector layers, and this transparent image of a cat as the mask/silhouette.

Now we can use this cat as-is for the mask, but it won't look great. I would recommend using photoshop to turn it into a black and white image, or if you just want the silohuette, play with the levels.

In the Opacity menu of the Control or Appearance tabs, click the button that says "Make Mask"
Your menu should now look like the right-hand side.

In the opacity menu, there are now two boxes. One shows the image, the other shows the mask. If you've used masks in photoshop this should be very familiar. Click on the mask square, and paste in your mask image. You may need to move the mask image around, but eventually you should get a result somewhat like the product below.

As you can see, the b&w mask has more detail, but gets lost in a busy background like the stars. The mask with increased contrast paints a more defined edge, but loses all detail.


Disneyland Discount on Paris Visite Pass?

Question: On Paris Visite Pass, there is 20% discount on Disneyland 1 day/2 parks ticket. But if I purchase the ticket online how can I get the discounted ticket using the Paris Visite pass?
Answer: I looked everywhere but couldn't find a really clear answer. I do think however, that you have to buy the ticket at the park and cannot buy online. This source for the same discount, but last year indicates:

The Disney ticket money-off deal is until 7th November 2013 on presentation of a valid Paris Visit Travel Pass at the Disney Parks ticket desk.

I found the same for 2012, so it's probable it will still be the same now.
Comment: thanks for your reply.
I am searching for this answer for so many days but didn't find any. I also emailed Disney land Official website and reply was that "We are unable to reply you regarding this" :P


Removing a video from camera roll

Question: I want to delete a video from my camera roll. Will it still exist in some kind of backup? This video was not uploaded to the cloud or the photo stream.
Answer: No.
Videos deleted from the camera roll are permanently gone from your phone. Even if you had your phone backed up to iCloud, your storage profile would update, after the video was deleted, so that the video would be removed from the cloud as well.
You will have to manually backup the video onto your computer, or email it to yourself before deleting it if you want it saved.

Removing a video from camera roll


Can not update to Safari 5.1 in Lion

Question: I have updated from Snow Leopard to Lion with Safari Version 5.0.5.
Now I can not update to Safari 5.1. There is no update in the Software Updater, and on the apple-download page, I only found a Safari 5.1 for Snow Leopard. When executing it, there is an error message, that it is for 10.6 only ().
Any idea how to get full screen browsing?
Comment: Lion ships with Safari 5.1. There's no need to update to it, you should already have it. To confirm click on Safari in the Menu and then "About Safari"
Comment: Just to state the obvious, therefore not an answer: Safari 5.1 was one of the update packages issued recently via the Software Update. The idea at Apple probably was to up-to-date your Mac before installing the Lion...
Comment: I have Safari 5.0.5 on Lion, so it seems not to ship with 5.1! I guess I did not update to 5.1 on Snow Leopard. Is there way to do it now? I've seen comments of people going back to Snow Leopard, update Safari to 5.1, then going to Lion. That seems to painful to me.
Answer: This helped: https://discussions.apple.com/message/15753211#15753211

Can not update to Safari 5.1 in Lion


Using mutual authentication, should I still worry about message integrity and replay attack?

Question: I'm trying to secure a REST API, our situation is that every client connecting to this API will also have a certificate signed by our own CA. Because of this, I think we can use the client certificate as an authentication mechanism, and install our root certificate on the webserver for verification and then use mutual authentication through HTTPS. We intend to do this with nginx so it's as simple as requiring nginx to have client verification on. However, I'm unclear about whether I should still timestamp and sign each request, should I still worry about message integrity and replay attack? Is there anything other attacks I should guard against?
Answer: As SSL ensures that the communication channel is secure from both tampering and snooping, there is no need to do more to ensure message replay and integrity.
This assumes that you are doing a secure authentication by validating the client cert, making sure it hasn't been revoked and isn't expired, is matched to the correct user, etc...
Answer: Yes, you can use the certs for mutual authentication. This would get you integrity checking, authentication, and encryption in transit for free, as long as the certificate is validated on each connection.
However, when you say protect against replay attacks, at the application level, you should still perform the necessary checks for replaying of messages.
Comment: Can you elaborate more on performing checks for message replay?


What is a ground loop and how does a common ground reduce video noise?

Question: To reduce video noise, it is often recommended to add a common ground between VTX and camera to avoid ground loops. What is a ground loop, how does it add video noise and how can a common ground negate its effects. Thanks.
Answer: If enough current flows and two ground pads are far enough apart, there might be a voltage difference between them because of the resistance in the PCB:s traces. That's called a ground loop.
As for why that causes noise; if the camera and the VTX have different reference points, a signal sent from the camera won't be received correctly by the VTX, and since a PAL or NTSC (The types of video that is used for analog FPV systems) signals use less than one volt, even a small in potential can cause video noise that will appear as horizontal bars moving vertically.
Here is an some more information if you would like to read more about it
Comment: Excellent, thank you for that explanation
Comment: No problem. I'd be happy if you marked this as the answer if you think it is!
Comment: I'm going to leave this question open for a little longer to invite more answers, however I feel that you have explained it very well so will be happy to mark this as the answer shortly. Thanks!


Blog Module for Sitecore 9

Question: Installing WeBlog latest version with Sitecore 9 is breaking Sitecore instance. Are there any other blog module which can work with Sitecore 9 and SXA? Thank you,
Comment: Hi @NabilOrfali , Have you managed to upgrade the WeBlog module to be compatible with Sitecore 9?
Comment: We've just finished upgrading WeBlog to Sitecore 9 and made it work with SOLR. Doing some QA right now, and I will be checking in the upgraded code to GitHub in a few days for everybody to use. Please reach out for any questions.
Answer: You can build a blog on top of SXA
I've created a step by step tutorial how to do it here
Here are default renderings that can be used on blog.

To display posts on homepage you could use Page List or Search Results

If you need comments there are FB comments, Disqus
Screenshots come from XA.Reference site. If you are not sure how to configure them, install it and play.
Comment: How to create a folder structure (year/month) for blog posts under 'blog root'?
Comment: Read this section of my blog post. https://alan-null.github.io/2017/12/sxa-blog#blog-base-partial-design
Comment: When creating new blog posts under blog home, The content tree creates time and date folder structure. Is there a way to only create year and month only? I followed exact steps but content tree has four different folder before blog post entry (ex: 03 -> 05 -> 19 -> 34 -> blog post1)
Comment: https://alan-null.github.io/2017/12/sxa-blog#faq -> How I can change URL slug
Answer: WeBlog is an open source repository so one solution for having a Sitecore 9 version of the WeBlog module is for you to fork it and update it to Sitecore 9. This will help you and also the community who already use WeBlog!
Otherwise, as Alan mentions, SXA is a great solution for this.

Blog Module for Sitecore 9


Google Analytics account transfer

Question: Is there a way to transfer Google Analytics account from one account holder to another?  The original account holder was managing the site via MCC.  That person is no longer associated with the website and would like to bring analytics control inhouse. Any ideas?
Answer: Instructions for doing this are buried in seemingly-unrelated documentation for merging Apps accounts. Give that a shot. I'll leave the specifics over there, as it may change at some point, but the overview is:

Add access for a new user.
Make them an admin.
Log in as them and delete the previous admin.

Google Analytics account transfer


Re fermentation

Question: I have 2, 6 gallon carboys, one apple & the other peach. The apple is bubbling really good, the peach not at all from what I have seen.
Can/should I add more yeast or sugar to kick start it?
Comment: We're gonna need a lot more information before we can assess what the problem is.  Is this a cider?  If so, what's your ingredients, what did you use for yeast?  What was your original gravity?  What was your process for extracting the juice?  How long have they been fermenting for.  The more thorough you are with your question, the better the odds are you'll get the answer you need.  Right now we'd just be guessing blindly.
Comment: I am new to this so I did not know about gravity. The mix is about two weeks now.
Comment: Again, I am new to this home brewing, I did not take a original gravity reading, but am going to do so tonight after getting the tool to do so. The ingredents used where sugar, peaches and a fruit yeast, we got the yeast at a local home brew supply shop. We placed the peaches into our buckets and let sit, per what we read. We then squeeze it through a chees cloth, it has been sitting like that almost two weeks now.  The apple wine we are trying to make, we started this about a week ago. That jug is perking away quite nice.
Comment: How much sugar and peaches did you add?  What kind of sugar and peaches did you use (if you have URLs to where we can read about them, all the better)?  Did you press/juice them?  Are they sitting in the carboy whole/sliced?  What is the exact provider and strand of yeast used (again, URLs would be helpful).  Again, the more detailed information you can provide regarding your ingredients, and the steps taken (step-by-step is ideal), the better we'll be able to help.
Comment: And definitely check the gravity when you get whichever tool you go with for measuring.  While there's insufficient information thus far to do anything other than speculate, there is always the possibility that it has fermented all the way already, however much it could.
Comment: @RLB do you have the exact bill of fermentables, water volumes, boil times (if any), etc? Maybe we could help you make an assumption about your original gravity?
Answer: When you say bubble are you meaning the airlock? It could be an issue with the seal of the carboy. Sometimes there is a leak in the seal so the brew is "bubbling" (this happens with the CO2 escaping when the alcohol is being produced) but you just cant see it in the airlock. As the others say we will need more information to solve the issue for you but you can always try the brew and see if you can taste alcohol or just off fruit.
Comment: I agree - if you gently push the lid of the bucket, or squeeze the container, do you see bubbles in the airlock? if not then you have a leak somewhere.

Re fermentation


Anim Zemiros is highly anthropomorphic; how come we sing it in public?

Question: Shir HaKovod - Anim Zemiros. This is amazingly anthropomorphic and all that without even once the word כביכול  (= as if such a thing could be true). Admittedly the references come from texts such as Shir HaShirim but to make a poem from it, how come it's allowed?
Comment: Well, some customs don't sing it.
Comment: AY check the left column on the page after the one you linked to. The language there is pretty harsh but I actually remember some harsher language only I can't recall the source (although I do remember it was the Maharal)
Comment: I have heard that the question of whether or not to say this prayer has been around for quite a while. Have a look a what the Maharal has to say on the subject here ספר נתיבות עולם א - נתיב העבודה - פרק י"ב.
Comment: @DavidPerlman I found the perek at http://www.hebrewbooks.org/pdfpager.aspx?req=14202&st=%D7%A9%D7%99%D7%A8+%D7%94%D7%9B%D7%91%D7%95%D7%93&pgnum=117 Could you be more speciifc about the part I should read please?
Comment: @DavidPerlman Thank you; most interesting. Maharal is talking about the Shir Hayichud (not the Shir HaKovod) - although the same applies. His point (IMHO) is about excessive praise at the wrong time not about anthropomorphism.
Comment: @DoubleAA - The Lubavitch custom is not to say it; I don't think this is true in all Chasidic sects but perhaps it's from the writings of the Ari that it shouldn't be recited? He was famous for not reciting any piyutim except those from certain Rishonim.
Answer: The poet makes it very clear, before launching into these descriptions, that they are not literal:

אֲסַפְּרָה כְבודְךָ וְלא רְאִיתִיךָ. אֲדַמְּךָ אֲכַנְּךָ וְלא יְדַעְתִּיךָ:
בְּיַד נְבִיאֶיךָ בְּסוד עֲבָדֶיךָ. דִּמִּיתָ הֲדַר כְּבוד הודֶךָ:
גְּדֻלָּתְךָ וּגְבוּרָתֶךָ. כִּנּוּ לְתוקֶף פְּעֻלָּתֶךָ:
דִּמּוּ אותְךָ וְלא כְּפִי יֶשְׁךָ. וַיַּשְׁווּךָ לְפִי מַעֲשיךָ:
הִמְשִׁילוּךָ בְּרוב חֶזְיונות. הִנְּךָ אֶחָד בְּכָל דִּמְיונות:
I shall relate Your glory, though I see You not; I shall allegorize You, I shall describe You, though I know You not.
Through the hand of Your prophets, through the counsel of Your servants; You allegorized the splendrous glory of Your power.
Your greatness and Your strength, they described the might of Your works.
They allegorized You, but not according to Your reality, and they portrayed You according to your deeds.
They symbolized You in many varied visions; yet You are a Unity containing all the allegories.

(Hebrew text of lines 5 - 9 copy/pasted from Sefaria. English Translation from the Artscroll Siddur.)
That sounds to me like five lines of "כביכול ."
Comment: The Koren/Sacks translation rhymes in English. 100x cooler IMO.
Comment: @DoubleAA, If you want to edit in the K/S translation, assuming it doesn't water down the point I'm getting at here, feel free to.
Answer: I think there's no problem using anthropomorphic images if:-

You are using only whatever already is said in ktuvim by neviim.
You do not take it seriously as literal description. (like you say the "Shemesh shak'a" though you know it has not, it just hidden from your eyes currently)
Comment: Boris. Agree (1). My point is about (2). Is there not a big danger in saying these things out loud so everyone can hear them and maybe (ch"v) be mistaken?
Comment: קהל: דִּמּוּ אוֹתְךָ וְלֹא כְּפִי יֶשְׁךָ, וַיְשַׁוּוּךָ לְפִי מַעֲשֶׂיךָ
חזן: הִמְשִׁילוּךָ בְּרֹב חֶזְיוֹנוֹת, הִנְּךָ אֶחָד בְּכָל דִּמְיוֹנוֹת
Sorry for English description but it goes more or like that:- "They described you but not as you are, and imagined you only only by your deeds". "Compared you in all their visions but you are the one in'em all."  Cat it be more clear that author does not mean to take the comparison literally. if there's danger of misunderstanding that  should be not said. But that is true for anything including the even some parts of humash.


Chemical equilibrium and stoichiometry

Question: In reactions that go until the end the stoichiometric number indicates the exact amounts of reactants and products you will get. However, this is not the case in equilibrium reactions and you will get a different amounts (concentrations) than what exhibits the stoichiometric numbers.
$$\ce{Na + Cl -> NaCl}$$
You will get in the end 1 mole of NaCl from 1 mole of Na and one mole of Cl.
$$\ce{2SO3<=>2SO2 + O2}$$
In equilibrium you will not get 1 molar of $\ce{O2}$ and 2 molar of $\ce{SO2}$ from 2 molar of $\ce{SO3}$.
Then what do the stoichiometric numbers indicate in equilibrium?
Comment: They indicate that for each mole of O2 you will get two moles of SO2.
Comment: This is true because the stoichiometric coefficients tell you so. Yes, you might get totally different molar concentrations. But whatever they might be, the concentration of SO2 will be twice that of O2.
Comment: How is it true? You will get totally different mollar concentrations based on Kc. I can't catch the issue exactly.
Answer: Let us take the example of your equation:
$$\ce{2SO3<=>2SO2 + O2}$$
The stoichiometric coefficients represent two facts:

If 2 mole $\ce{SO3}$ reacts, it will give 2 mole $\ce{SO2}$ and 1 mole $\ce{O2}$ but one needs to remember here that all of the 2 moles will not react. But the number of moles that do dissociate, give products in the above ratio i.e. if initially have 2 moles of $\ce{SO3}$ and degree of dissociation is 50%, then we will have 1 mole of $\ce{SO3}$ reacting to give 1 mole of $\ce{SO2}$ and half mole of $\ce{O2}$
The stoichiometric coefficients also provide the powers to which the concentrations of each compound will be raised to in the expression for equilibrium constant $$K_\mathrm c = \frac{[\ce{SO2}]^2[\ce{O2}]}{[\ce{SO3}]^2}$$
Comment: OK thanks. The soft spot is that not all the reactants dissociate however the stoichiometric coefficients do represent the rations between the substances.

Chemical equilibrium and stoichiometry


Send push notification to mobile from lightning app

Question: Is it possible to send a push message from a salesforce lightning app? For instance suppose a record has been created and I want a push notification in my mobile phone. I am fairly new at this and have no idea where to start so any help would be appreciated.
Answer: Actually, the question is about sending push notification from a Lightning app. The provided link is for native and hybrid mobile apps (not Lightning apps or Lightning pages).
To clarify, Lightning framework by itself does NOT provide any support for push notifications. You will need to wrap your Lightning pages into a hybrid application and use an approach such as Apex triggers to generate push notifications for mobile clients.
Below is an example which shows a push notification being generated when a case is updated (pure Apex code, no Lightning)
<code>trigger caseAlert on Case (after update) {

    for(Case cs : Trigger.New)
    {
        // Instantiating a notification
        Messaging.PushNotification msg =
            new Messaging.PushNotification();

        // Assembling the necessary payload parameters for Apple.
        // Apple params are:
        // (<alert text>,<alert sound>,<badge count>,
        // <free-form data>)
        // This example doesn't use badge count or free-form data.
        // The number of notifications that haven't been acted
        // upon by the intended recipient is best calculated
        // at the time of the push. This timing helps
        // ensure accuracy across multiple target devices.
        Map<String, Object> payload =
            Messaging.PushNotificationPayload.apple(
                'Case ' + cs.CaseNumber + ' status changed to: '
                + cs.Status, '', null, null);

        // Adding the assembled payload to the notification
        msg.setPayload(payload);

        // Getting recipient users
        String userId1 = cs.OwnerId;
        String userId2 = cs.LastModifiedById;

        // Adding recipient users to list
        Set<String> users = new Set<String>();
        users.add(userId1);
        users.add(userId2);

        // Sending the notification to the specified app and users.
        // Here we specify the API name of the connected app.
        msg.send('Test_App', users);
    }
}
</code>
Answer: Yes, Yes it is.
There are two ways of doing this. First, is to use the Marketing Cloud's JB4A SDK for either Android or IOS. The second is to use the core platform's push notification features.
I suspect, since you've not mentioned the Marketing Cloud that you're wanting to use core features. Here's some documentation on how to do that:
https://developer.salesforce.com/docs/atlas.en-us.pushImplGuide.meta/pushImplGuide/pns_registration_process.htm


Blender command line open template

Question: Hi and thanks for reading.
I'm newbie and have problem to solve with Blender.
We have a upper level app which will open a template of Blender with a button in GUI (for make difference startup file and userpref file).
But I can't found in docs that argument for open template file so I'm asking community for help if this option is possible, if not hope anyone can help me Python script option for this problem.
Thanks again!
Comment: What do you mean by template? Is it just a blend file you want to open?
Comment: I'm just copy from docs: "Application templates are a feature that allows you to define a re-usable configuration that can be selected to replace the default configuration, without requiring a separate Blender installation or overwriting your personal settings."
Answer: There is no CLI option to choose which application templates is open at startup, you need to use python to tell blender to open one of the templates.
You need to call the bpy.ops.wm.read_homefile() operator, using --python-expr in the CLI arguments should be enough -
blender --python-expr "import bpy; bpy.ops.wm.read_homefile(app_template='usertemplate')"

Blender command line open template


troubleshooting Finder (and disk access?) speeds — Dropbox extension problems?

Question: I am on Yosemite 10.10.3, though in the public beta program (which now is in sync with releases). I am also in the Dropbox beta, now on 3.5.58, for what it's worth.
File access is curiously slow now. It could be a hardware issue, like the old spinning HDD dying in my MBP. That said, things often stall when Save or Open dialog boxes open up, and more often than not the Dropbox extension crashes afterwards.
Displaying the contents of folders is also slow, in the dialog boxes or Finder windows themselves, like in this question.
How should one start diagnosing such an issue?
I understand I could forget the Dropbox beta. I could also talk to them. But this has been crashing ever since Yosemite went to public beta testing, and no update to the OS nor Dropbox ever fixed this. The Dropbox beta is not that far ahead from the release anyway.
Is there anything to check here other than a reinstall or even a migration to a new mac?
I regularly run Onyx, so everything what it would do (incl. permission repairs) has been done recently. That said, Onyx's hardware check regularly complains about the disk, which needs to repaired after booting from the recovery disk. I don't know why this is recurring. Esp. as the problem is usually the disk size being off by a little.
[I'd paste screenshots of Disk Utility from booting into internet recovery, but they do not upload. Here are two links to them on Dropbox.]
I checked system.log, and saw no I/O errors, though most of my log is filled with these lines every second:
Apr 23 15:07:23 dhcp-7-125 com.apple.xpc.launchd[1] (com.apple.photostream-agent[92911]): LaunchServices returned a bundle URL that does not match with the LoginItem's known association.
Apr 23 15:07:23 dhcp-7-125 com.apple.xpc.launchd[1] (com.apple.photostream-agent): Service only ran for 0 seconds. Pushing respawn out by 10 seconds.
Apr 23 15:07:23 dhcp-7-125.nber.org com.apple.usbmuxd[49806]: HandleUSBMuxDictionary client 0x100608890-duet/NULL using library 1.2.5, running usbmuxd-344.6
Apr 23 15:07:23 dhcp-7-125.nber.org com.apple.usbmuxd[49806]: MuxTCPInputSCE received RST for 0x11-b22be791bfd836141f0489b3045fe82d713378b2@0xfd120000:2345->0x100608890-duet/NULL:33702: handleConnectResult: failure - 61

If this can be related to the Dropbox issues, here is another extension crash report from this morning. (Too large to show here, link is to a txt on Dropbox.) I've been sending these to Apple since last summer or so, neither OS X updates or Dropbox betas and releases seem to have fixed the issue.
Answer: Kill the service from terminal:
$ launchctl remove com.apple.photostream-agent

Then go into Apple / System Preferences... and check your iCloud settings. Often this is caused if iCloud photos or disk is on, but the Photos app has sharing off.