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Preparation of MWCNTs/PB Composite Material Modified Electrode with Vapor-surface Sol-gel Deposition

A novel amperometric biosensor was fabricated by incorporation of MWCNTs/PB composite material modified gold electrode with a vapor deposition method.The modified electrode showed excellent catalytic activity for hydrogen peroxide,which combined the merits of the synergic catalysis effects of PB and MWCNTs.In addition,glucose oxidase(GOD) was immobilized on MWCNTs/PB modified electrode,and the glucose biosensor exhibited fast response time and high sensitivity.This method could widen the application area of sol-gel and provided a commendable model system for research the synergic catalysis effects.

In this paper, a modeling and simulation method for planar interdigitated ruthenium oxide MEMS supercapacitor was proposed based on the electrochemical reaction mechanism of supercapacitor. The study simulated the planar interdigitated ruthenium oxide MEMS super capacitor using Comsol software. The highly accurate charge and discharge curves of the super capacitor, electric potential distribution graph and the concentration distribution graph were got through simulation. The effects of two structure-parameters were discussed in the research.

eng_Latn

Composite Substrates for GaN Growth

This work reports on the development of composite substrates, realised using the Smart Cut™ technology. A thin film of monocrystalline SiC or Si is transferred onto polycrystalline SiC. Those composite substrates can be prepared for 4” size and over as well. GaN layers are grown onto the above substrates in order to demonstrate that they can be used for the fabrication of GaN high electron mobility transistor (HEMT) devices. The epitaxial nitride layers have been grown successfully and exhibit state of the art GaN HEMTs grown on silicon in terms of crystal and electrical properties.

ABSTRACTIn the present study, a new organoclay adsorbent for the adsorption of isoniazid (INH) was produced with the modification of bentonite using green chemistry approach. Glycine was used for t...

eng_Latn

Degradation of Single‐Layer and Few‐Layer Graphene by Neutrophil Myeloperoxidase

Biodegradability of graphene is one of the fundamental parameters determining the fate of this material in vivo. Two types of aqueous dispersible graphene, corresponding to single-layer (SLG) and few-layer graphene (FLG), devoid of either chemical functionalization or stabilizing surfactants, were subjected to biodegradation by human myeloperoxidase (hMPO) mediated catalysis. Graphene biodegradation was also studied in the presence of activated, degranulating human neutrophils. The degradation of both FLG and SLG sheets was confirmed by Raman spectroscopy and electron microscopy analyses, leading to the conclusion that highly dispersed pristine graphene is not biopersistent.

Abstract The moving parts of any mechanism and machine parts are always subjected to a significant wear due to the development of friction. It is utmost important aspect to address the wear problems in present environment. But the complexity goes on increasing to replace the worn out parts if they are very precision. Technology advancement in surface engineering ensures the minimum surface wear with the introduction of polycrystalline nano nickel coating. In this study, tribological behavior of the nano nickel coating developed through pulsed electro deposition technique has been investigated. The nano structured coated specimen were admitted for pin and disc method of wear testing. The nature of wear has been examined over the surface of the specimen through Atomic Force Microscope (AFM) in order to validate the prior results. The results yielded from pin and disc and AFM registered the negligible deviations.

eng_Latn

Studies on electro-conductive yarns prepared by in situ chemical and electrochemical polymerization of pyrrole

This work deals with preparation, characterization, and performance of electro-conductive yarns prepared by in situ chemical and electrochemical polymerization of pyrrole. Box-Behnken design in conjunction with response surface analysis has been used to study the electrochemical polymerization process. The effect of electrochemical process parameters on the electrical resistivity has been reported. Further, the electrical and electromechanical behaviour of the electro-conductive yarns thus produced has also been reported. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The photopyroelectric method in a non contact detection configuration is proposed to study water migration in starch sheets. This allows the exchange of humidity between the moist atmosphere and the starch sample during the experiment. The sensitivity for the total water content measurement was about 0.3%. A theoretical model was developed, taking into account a continuous depth profile of humidity in the starch sample. A water profile in the material and its evolution in time were evidenced when exposing one side of the sample to a humid atmosphere.

eng_Latn

Ionizing-radiation-resistant polycarbonate resin composition, and molded product comprising same

A polycarbonate resin composition of the present invention comprises: a polycarbonate resin; a polyalkylene glycol; an epoxy ester compound containing an ester group and an epoxy group; and a halogenated polycarbonate oligomer. The polycarbonate resin composition has excellent discoloration resistance, color, hydrolysis resistance, flame retardancy and the like even after being irradiated with ionizing radiation.

In this paper, a modeling and simulation method for planar interdigitated ruthenium oxide MEMS supercapacitor was proposed based on the electrochemical reaction mechanism of supercapacitor. The study simulated the planar interdigitated ruthenium oxide MEMS super capacitor using Comsol software. The highly accurate charge and discharge curves of the super capacitor, electric potential distribution graph and the concentration distribution graph were got through simulation. The effects of two structure-parameters were discussed in the research.

eng_Latn

Investigation of the analyticity of dissipative–dispersive systems via a semigroup method

Abstract In this work, we study the analyticity of Kuramoto–Sivashinsky type equations and related systems by exploring the applicability of the semigroup method, which was developed in Collet et al. [5] . We establish the analyticity, with respect to the spatial variable in a strip around the real axis, for a variety of dissipative–dispersive systems, which possess universal attractors. We also provide lower bounds for the width of the strip of analyticity.

Abstract Herein we report the facile synthesis of freestanding silver dendrite (AgD)/graphene oxide (GO) composite membranes, and demonstrate their use as an efficient and robust substrate with large-area uniformity and good reproducibility for surface-enhanced Raman scattering (SERS) applications. The as-prepared composite membranes exhibit excellent sensitivity for detecting rhodamine 6G and 5,5′-dithiobis-(2-nitrobenzoic acid). The results suggest that AgD/GO nanocomposite membrane holds great promise as a high-performance SERS substrate for plasmonic sensing applications.

eng_Latn

Depolarizing field in temperature-graded ferroelectrics from an atomistic viewpoint

An atomistic approach for computing the depolarizing, or internal, electric field in materials with inhomogeneous polarization is developed. Application of the approach for studying the depolarizing fields in technologically important (Ba0.7Sr0.3)TiO3 ferroelectric alloy with temperature gradients has revealed the intrinsic features of these fields as well as their role in the establishment of polarization gradients. It is found that the depolarizing fields are inhomogeneous and can be tailored to yield both zero and non-vanishing potential drops. Such findings could pave the way to unusual thermoelectric materials, photovoltaics and locally conducting materials, all of which are at the frontier of current research.

Delipidation of liver homogenates, using an organic solvent system which does not denature proteins, increases measurable ferritin by 25-33%, compared to ferritin concentrations by standard heat supernatant assays. When applied to polyacrylamide gradient gels, lipid-associated ferritin does not enter the gel but after delipidation, this ferritin co-migrates with cytosolic ferritin and with purified liver ferritin. The biological significance of the association of ferritin with lipid has yet to be examined.

eng_Latn

Neurobiological actions of cysteamine.

Somatostatin (SS)-related peptides act within discrete brain regions to inhibit adrenal epinephrine (E) secretion, to prevent hypothermia, and to produce hyperthermia. Depletion of brain concentrations of these SS-related peptides using cysteamine (CSH) or central administration of an SS receptor antagonist increases adrenal E secretion and impairs thermoregulation. These actions of CSH and the SS receptor antagonist are reversed by administration of SS into the central nervous system. These results support the hypothesis that endogenous brain SS-related peptides are involved in the regulation of adrenal E secretion and thermoregulation.

The Ni-SiC nano-composite coatings were prepared on the ring of stainless steel by using of high frequency pulse electroplating. Orthogonal experiment was used to study optimal dosage of the dispersant. The effect of some factors, such as current density, pH value, temperature , addition agent and so on, were studied. The characterization of Ni-SiC nano-composite coatings were studied by wear test. The effect of pulse frequency and the SiC concentration in the electrolyte on the wear resistance of Ni-SiC nano-composite coatings were studied. The morphology of the nano-composite coatings in wear test before and after were analyzed by SEM and the metaloscope photographs. The results show that Ni-SiC nano-composite coatings of high frequency pulse electroforming have better performance of wear resistance.

eng_Latn

Experimental study on viscosities of TiO_2-H_2O nanofluids

Four different concentration TiO2-H2O nanofluids with 20 nm TiO2 were prepared with supersonic oscillator through appending hydrophilic dispersant into deionized water.The viscosities of TiO2-H2O nanofluids and deionized water were measured at different temperatures.The results showed that the viscosities of nanofluids increased apparently compared to the deionized water.And the viscosities varied inversely with the temperature of the TiO2-H2O mixture system.The results also demonstrated that the TiO2-H2O nanofluids were Newtonian fluids.

A method for predicting organic compound volatilization rates under turbulent liquid and gas conditions is developed. The reference compounds are classified according to their physico-chemical properties. The mass transfer coefficient (K(OL)) ratios for organic solutes to the reference compounds are constant for a wide range of environmental conditions, including liquid or air turbulence, or both at once. The obtained results indicate that when the environmental conditions are the same the determination of the volatilization rates is strongly dependent on the solute properties and the chemical structure. The presented method can more effectively estimate the volatilization rates of the solutes than the traditional one under various environmental conditions especially for low volatility solutes. The advantages and disadvantages of the traditional method are also discussed.

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Preparation of PZT thin films on stainless steel using electrochemical reduction

Abstract PZT perovskite films which were strongly adhered to stainless steel were prepared by electrochemical reduction in solutions containing TiO 2+ , ZrO 2+ , and Pb 2+ ions. The composition of the PZT films was easily controlled by the composition in the solution and the applied cathodic potential during the electrolysis. Heat treatment at 600°C was necessary for crystallization, because the as-deposited oxide films were amorphous. Pb was deposited as a metal, while Zr and Ti were deposited as oxides and/or hydroxides during the electrolysis. The average of the dielectric constants of the PZT films prepared by the present method was more than 500.

Objective To study the best extracting technology of Compound Taizishen Granule prescription.Methods The total polysaccharides and total saponins were determined by UV spectrophotometer.With the content of total polysaccharides and total saponins as comprehensive indexes,orthogonal test was applied to investigation of the water addition,extraction time,and extraction times for optimizing the best extracting technology.Results The best extracting technology was using 10 times the amount of water,extracting 3 times and 1.5 h per time.Conclusion The extraction technology is safe and effective,which can be used as extraction for Compound Taizishen Granule prescription.

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Fluorescence Determination of Merucury(II) Using a Thymine Aptamer

A label-free thymine-rich sequence and a molecular beacon were synthesized to construct a highly sensitive and selective fluorescence probe for the determination of mercury(II). The aptamer of the thymine-rich sequence selectively bonded with mercury(II) with an accompanying change in the fluorescence intensity of the molecular beacon due to the higher affinity of the aptamer with mercury(II). The limit of detection was 12.7 nanomolar, and a linear relationship was obtained between the fluorescence and mercury(II) concentrations up to 1 micromolar. The assay was highly selective for the mercury(II) and not significantly affected by other metal ions.

Abstract In the application of some polymers as track detectors, the attention should be paid to the fact that the track recording properties of these polymers are changed under the influence of certain parameters, such as the electromagnetic radiations and environmental conditions. In this work the etching effects of 60Co gamma irradiated CR-39 polycarbonate have been studied. For deeper study of the structural changes in CR-39, the FTIR and UV–visible spectra have been analyzed. The FTIR spectra shows considerable changes due to the gamma exposure. The contribution of degradation mechanism is discussed.

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A theoretical and experimental study of the waveform in potentiometric stripping analysis with a rotating mercury-film electrode-the reversible case.

Abstract The potential-time transient in potentiometric stripping analysis with a rotating mercury-film electrode is simulated digitally by means of the finite-difference Cranck-Nicolson method. Good agreement with experimental results is obtained. The relations between peak shape and signal duration for reversible analyte systems are discussed, and it is shown that severe peak overlap gives rise to distortions of the composite signal.

Plutonium metal scrap, oxide, and other residues are processed at Rocky Flats using both pyrochemical and aqueous methods. The pyrochemical processes currently in production include electrorefining, fluorination, hydriding, molten salt extraction (MSE), calcination, and reduction operations. Aqueous processing and waste-treatment methods involve nitric acid dissolution, ion exchange, solvent extraction, and precipitation techniques. An overview of the chemistry involved in these operations will be given. Research in progress to improve these operations, or develop new processes, will also be presented.

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ROS and NF-kappa B are involved in upregulation of IL-8 in A549 cells exposed to multi-walled carbon nanotubes

Fujian Province for Young Scientific Researchers, China [2008173097]; Ministry of Science and Technology, China [2006CB93300]

In this paper, a modeling and simulation method for planar interdigitated ruthenium oxide MEMS supercapacitor was proposed based on the electrochemical reaction mechanism of supercapacitor. The study simulated the planar interdigitated ruthenium oxide MEMS super capacitor using Comsol software. The highly accurate charge and discharge curves of the super capacitor, electric potential distribution graph and the concentration distribution graph were got through simulation. The effects of two structure-parameters were discussed in the research.

eng_Latn

Efficient and Chemoselective Deoxygenation of Amine N-Oxides Using Polymethylhydrosiloxane

Deoxygenation of aromatic and aliphatic amine N-oxides to the corresponding amines is achieved under mild conditions. The reagent combination employed for this transformation is polymethylhydrosiloxane (PMHS) in the presence of either tetrakis (triphenylphosphine) palladium (0) [Pd(PPh 3 ) 4 ], titanium (IV) isopropoxide [Ti(i-PrO) 4 ] or palladium on carbon (Pd/C).

Abstract Production anti-scorpion serum fraction requires washing water containing important quantities of (NH4)2SO4. This study presents a combination of the ultrafiltration and the electrodialysis to recover this salt. The application of ceramic ultrafiltration membrane has helped to reduce pollution due to organic matter by completely retained the proteins with an apparent rejection coefficient close to unity. The optimum hydrodynamic parameters such as the average transmembrane pressure and tangential flow rate were determined for ultrafiltration cell. The combination of the UF with the ED allowed concentrating the NH 4 SO 4 salt with a recovery yield of about 74%.

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ELECTROCHEMICAL POLYMERIZATION OF PYRROLE ON Ni-ELECTRODE AND THE THERMAL BEHAVIOR OF POLYPYRROLE

Pyrrole(PY) was electrochemically polymerized on Ni electrode by using Et4N(TsO) as electrolyte in ethyleneglycol/acetonitrile solvent with constant current or constant voltage. The electrical conductivity is around 10 s/cm. TGA results show that the film is stable under 300℃. Results of elemental analysis, FTIR, SEM are also reported.

The photopyroelectric method in a non contact detection configuration is proposed to study water migration in starch sheets. This allows the exchange of humidity between the moist atmosphere and the starch sample during the experiment. The sensitivity for the total water content measurement was about 0.3%. A theoretical model was developed, taking into account a continuous depth profile of humidity in the starch sample. A water profile in the material and its evolution in time were evidenced when exposing one side of the sample to a humid atmosphere.

yue_Hant

Compounds and their preparation and use in the synthesis of the racetam Bois

The present application provides a compound of formula IV and II. The present application also provides for the synthesis of compounds of formula II and use of racetam Bois synthetic methods. The present application relates to the method the raw material is readily available and cheap, can be prepared with high optical purity Bois racetam.

In this paper, a modeling and simulation method for planar interdigitated ruthenium oxide MEMS supercapacitor was proposed based on the electrochemical reaction mechanism of supercapacitor. The study simulated the planar interdigitated ruthenium oxide MEMS super capacitor using Comsol software. The highly accurate charge and discharge curves of the super capacitor, electric potential distribution graph and the concentration distribution graph were got through simulation. The effects of two structure-parameters were discussed in the research.

eng_Latn

Batch Supercritical Hydrothermal Synthesis of CeO2 Nanoparticles

CeO2 nanoparticles with diameter of about 5 nm were prepared by batch supercritical hydrothermal synthesis method at 390 °C without additional treatment. It was found that the characteristics of products depended on the pH value, reactant concentration (C0), and reaction temperature. The reaction time and coexisting cations (Li+, Na+ and K+) had little effect on the size and morphology of CeO2 particles. Uniform CeO2 nanoparticles were synthesized at 390 °C, pH = 9 and C0 = 0.06 M. The mechanism for batch supercritical hydrothermal synthesis of CeO2 nanoparticles is discussed.

Objective To study the best extracting technology of Compound Taizishen Granule prescription.Methods The total polysaccharides and total saponins were determined by UV spectrophotometer.With the content of total polysaccharides and total saponins as comprehensive indexes,orthogonal test was applied to investigation of the water addition,extraction time,and extraction times for optimizing the best extracting technology.Results The best extracting technology was using 10 times the amount of water,extracting 3 times and 1.5 h per time.Conclusion The extraction technology is safe and effective,which can be used as extraction for Compound Taizishen Granule prescription.

eng_Latn

Influence of three mechanical bileaflet prosthetic valve designs on the three-dimensional flow field inside a simulated aorta

Dynamic particle image velocimetry study of the aortic flow field of contemporary mechanical bileaflet prostheses

Polymer Nanocomposites—A Comparison between Carbon Nanotubes, Graphene, and Clay as Nanofillers

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Study Finds Dietary Link to Risk of Eye Disorder

Certain kinds of carbohydrates may play a role in the development of age-related macular degeneration, a new study suggests.

If you think you spend too much time stuck in front of a computer screen, spare a thought for bleary eyed gamer Eric Furrer.

kor_Hang

Beta carotene pills may not save vision

Carrots, rich in beta carotene, long have been thought to sharpen eyesight, but a new study suggests that beta carotene pills are powerless against a common type of vision loss among older people.

Our brains can turn down our ability to see to help them listen even harder to music and complex sounds, say experts.

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Where are green eyes most common?

There is no green pigment in green eyes; like the color of blue eyes, it is an optical illusion; its appearance is caused by the combination of an amber or light brown pigmentation of the stroma, given by a low or moderate concentration of melanin, with the blue tone imparted by the Rayleigh scattering of the reflected light. Green eyes are most common in Northern and Central Europe. They can also be found in Southern Europe, West Asia, Central Asia, and South Asia. In Iceland, 89% of women and 87% of men have either blue or green eye color. A study of Icelandic and Dutch adults found green eyes to be much more prevalent in women than in men. Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry, about 16%.

English is used as a second language in parts of Southern Europe. As a primary language, however, English has only a small presence in Southern Europe, only in Gibraltar (alongside Spanish) and Malta (secondary to Maltese).

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Impact of pigment dispersion on trabecular meshwork cells

Purpose ::: Dysfunction of the trabecular meshwork (TM) in pigmentary glaucoma contributes to increased aqueous humor outflow resistance and intraocular pressure. In this study, we investigated the effect of pigment dispersion on trabecular meshwork cells.

Key message ::: Distributional patterns of pectin and hemicellulose epitopes in the phloem of four hardwoods vary between cell types including sieve tube elements, companion cells, parenchyma and sclerenchyma and between tree species.

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do dietary supplements(like claraxon)improve vision?

No.\n\nThe FDA is just releasing a massive study of various supplements, and almost none of them work. This one seems less plausible than most. What about vision would be related to a supplement? Your body supplies your eyes with what they need, we evolved that way.

Go to www.naturalcures.com. There, you can either join the site (with a fee) or find the information concerning the newsletter.\n\nAlso, have you read the books? That is another way to support.

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of upto 10 Tb/in 2 . It uniquely differs from other proposed next-generation architectures because of its reliance on sophisticated two-dimensional signal processing algorithms. Recently, a number of contributions have been made in the development of read-channel models and detectors for TDMR systems. In this paper, we provide a detailed review on all important readchannel models under consideration. Our discussion focuses on the purpose of each of these models, placing a special emphasis on the suitability of the Voronoi model for the purpose of designing detectors. We also propose several detection schemes for TDMR based on the Voronoi model and present some numerical results.

We introduce a family of planar regions, called Aztec diamonds, and study tilings of these regions by dominoes. Our main result is that the Aztec diamond of order n has exactly 2n(n+1)/2 domino tilings. In this, the first half of a two-part paper, we give two proofs of this formula. The first proof exploits a connection between domino tilings and the alternating-sign matrices of Mills, Robbins, and Rumsey. In particular, a domino tiling of an Aztec diamond corresponds to a compatible pair of alternating-sign matrices. The second proof of our formula uses monotone triangles, which constitute another form taken by alternating-sign matricess by assigning each monotone triangle a suitable weight, we can count domino tilings of an Aztec diamond.

MLL1 regulates circadian promoters by depositing H3K4 trimethyl marks, whose levels are also modulated by the NAD+-dependent deacetylase SIRT1. SIRT1 is now shown to promote circadian deacetylation of MLL1, thus affecting MLL1's methyltransferase activity.

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Uncovering the Mechanisms of Shrimp Innate Immune Response by RNA Interference

Because of the importance of shrimp in world aquaculture, there is much interest in understanding their immune system in order to improve their resistance to pathogenic microorganisms. An effective tool in studying genes involved in the immune response in shrimp is RNA interference (RNAi). RNAi, first recognized as an antiviral response against RNA viruses, is a cellular mechanism that is triggered by double-stranded RNAs and results in the degradation of homologous genes. In this review, we describe the current studies of genes in shrimp that employed RNAi technology to elucidate or confirm their functions. We also review the potential of RNAi to elicit antiviral response in shrimp.

We study the Radiation-Induced Mismatch Enhancement (RIME) in 65 nm CMOS SRAM block designed for space applications. X-ray and heavy ion irradiation increase the number of non-rewriting cells.

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Detection of small non-coding RNAs.

Gene expression is regulated at several levels in plants, and one of the most recently discovered regulatory layers involve short RNAs. Short RNAs are produced through several pathways and target either mRNAs or genomic DNA. Different classes of short RNAs have slightly different sizes and detection of their accumulation is an important step in validating and studying non-coding short RNAs. Northern blotting is routinely used to detect short RNAs because it gives information about both the amount and size of the analysed short RNAs. Choice of the right RNA extraction protocol is crucial when short RNAs are being studied, because several routinely used commercial RNA extraction kits do not yield any short RNAs. This chapter describes optimised RNA extraction methods, which give good yields of short RNAs, and separation, transfer and hybridisation protocols to study the accumulation of short RNAs.

A technique, whereby the radiation patterns of large size reflector antennas can be approximated by computers using a moment method without excessive computer time or memory, is described. Computational time increases only linearly with antenna size. There is no limit on the minimum reflector size (a single wire reflector can be analyzed). An example is discussed showing the radiation patterns of a truncated parabolic reflector excited by feeds displaced from the parabola focus.

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Stable expression of the chlorocatechol dioxygenase gene from Ralstonia eutropha NH9 in hybrid poplar cells.

The cbnA gene encoding chlorocatechol dioxygenase from the soil bacterium Ralstonia eutropha NH9 under the control of a modified cauliflower mosaic virus 35S promoter was introduced into a hybrid poplar (Populus tremula x P. tremuloides). Integration of the cbnA gene in transgenic poplar was confirmed by PCR and genomic Southern blot analysis. Expression of the cbnA gene was analyzed by Western blot analysis. Transgenic poplar calli efficiently converted 3-chlorocatechol to 2-chloro-cis,cis-muconate.

The lake sediments have registered the information of palaeoclimate and palaeoenvironment in the lake itself and the regional scale. This also leads to a complexity in study of the palaeolimnology by all kinds of proxies. How to purify these proxies to indicate the palaeoclimate has become a problem to be solved. Most of the proxies can qualitively identify the percentage of allochthonous and autochthonous organic components, e.g. δ13corg CD/TC. The model introduced in this note has provided a method of quantitatively calculating the amount of allochthonous organic carbon. As for determination of regulating parameters, i.e. A1 and As, further work is still in need.

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RNA editing: new insights into the storage and expression of genetic information.

Kinetoplastid flagellates, and possibly other parasites and viruses, have evolved a novel form of gene regulation at different phases of their life cycle by 'editing' their own RNA transcripts. This article discusses the significance of the process and proposes a hypothesis to explain how it may be done.

We study the Radiation-Induced Mismatch Enhancement (RIME) in 65 nm CMOS SRAM block designed for space applications. X-ray and heavy ion irradiation increase the number of non-rewriting cells.

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A simple procedure for the purification of yeast phenylalanine transfer RNA

Abstract For the past several years we have been attempting to study the secondary and tertiary structure of tRNAs + by means of chemical probes. In the course of this work it became necessary to obtain a highly purified species of tRNA. For two reasons we chose to purify yeast Phenylalanine tRNA. The nucleotide sequence of this molecule has been completely worked out ( RajBhandary and Chang [1968] ). Secondly, a simple and highly effective partial purification of this species has been obtained by Gillam et al. (1967) on benzoylated DEAE cellulose. In this communication we report the use of BD-cellulose to complete the purification of tRNA Phe .

Introduction A successful fi rst structure refi nement of lysozyme [1] already proved the value of standard XRPD laboratory instruments for protein structure research. In this contribution we will present new measurements and crystallographic analysis results of insulin and insulin derivatives performed on data from a PANalytical X’Pert PRO diffractometer used in different confi gurations. We additionally demonstrate that even fast measurements on a 96 well plate as used for polymorph screening purposes, result in high quality data, which is suitable for automatic crystallographic analysis like indexing [2] and LeBail [3] fi tting.

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A Double-Blind Study of the Effect of Ribonucleic Acid in Senile Brain Disease

A double-blind study to test the effect of orally administered ribonucleic acid upon the course of senile and arteriosclerotic brain disease failed to confirm the positive findings of other investigators. The authors conclude that RNA administered in this form does not appear to bring about improvement or reversal of senile brain disease.

It all clicks into place: A potent telomere-targeting small molecule has been identified by using the copper-free 1,3-dipolar cycloaddition of a series of alkyne and azide building blocks catalyzed by a non-Watson-Crick DNA secondary structure (see picture). This method rapidly identifies, otherwise unanticipated, potent small-molecule probes to selectively target a given RNA or DNA.

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CRISPR-Cas systems in bacteria and archaea: versatile small RNAs for adaptive defense and regulation.

CRISPR/Cas, the Immune System of Bacteria and Archaea

bim and lean interactions from the bim capability maturity model perspective : a case study .

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is RNA interference considered gmo

Abstract. The potential hazards posed by RNA interference (RNAi)–based pesticides and genetically modified crops to nontarget organisms include off-target gene silencing, silencing the target gene in unintended organisms, immune stimulation, and saturation of the RNAi machinery. new peer-reviewed paper in the journal Bioscience draws attention to potential hazards on nontarget species of pesticides and GMOs made with RNA-interference (RNAi) gene-silencing techniques.

RNAi Overview. RNA interference (RNAi) is a relatively new technology that is revolutionizing the way that researchers study mammalian gene expression. RNAi has had significant impact on the ease, speed, and specificity with which the loss of gene function analysis can be done in mammalian cells and animal models.

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This study addresses not only influence and selection of friends as sources of similarity in alcohol use, but also peer processes leading drinkers to be chosen as friends more often than non-drinkers, which increases the number of adolescents subject to their influence. Analyses apply a stochastic actor-based model to friendship networks assessed five times from 6(th) through 9(th) grades for 50 grade cohort networks in Iowa and Pennsylvania, which include 13,214 individuals. Results show definite influence and selection for similarity in alcohol use, as well as reciprocal influences between drinking and frequently being chosen as a friend. These findings suggest that adolescents view alcohol use as an attractive, high status activity and that friendships expose adolescents to opportunities for drinking. Language: en

Researchers have become increasingly interested in disentangling selection and influence processes. This literature review provides context for the special issue on network–behavior dynamics. It brings together important conceptual, methodological, and empirical contributions focusing on longitudinal social network modeling. First, an overview of mechanisms underlying selection and influence is given. After a description of the shortcomings of previous studies in this area, the stochastic actor-based model is sketched; this is used in this special issue to examine network–behavior dynamics. The preconditions for such analyses are discussed, as are common model specification issues. Next, recent empirical advances in research on adolescence are discussed, focusing on new insights into moderating effects, initiation of behaviors, time heterogeneity, mediation effects, and negative ties.

Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights.

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Analysis of Influencing Factors of Network Public Opinion Based on ISM

The purpose of this paper is to analyze the factors which influence the development of network public opinion.Interpretative structural modeling(ISM) was introduced into the analysis of the factors.The paper the attainable matrix,divides the matrix into several grades and parts,and sets up the harmoniousness structural mode.The ISM model can visually reflect the hierarchical relationship between various influencing factors,and provide the scientific basis for analyzing he public opinion more objective and comprehensive.

This article is the second of two parts. The first one was published in the issue no 2 of this same journal. The preseni study uses the dependency index and the youth ratio to describe the aging process both at regional and municipal levels. Our data show a yet moderate aging process in (he region. with an uneven distribution throughout the different municipalities.

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Family, kin, and the quest for community: A study of three social networks in early-modern Italy

The article probes seventeenth-century occupational and marriage data from three parishes in the Savoyard domains for isomorphisms with processes of collective mobilization. Analyzed as directed graphs, networks of marriage alliance display widely differing patterns in standard graph measurements and Regular Equivalence blockmodelling across the three parishes. Channeling flows of material and symbolic exchange conducive to different forms of political action, these network variations are in turn the outcome of unbalanced access by local kin groupings to vital resources.

National teams of students who participated in 2012 Erasmus Intensive Program ’Library, Information and Cultural Management – Academic Summer School’ were asked to do researches on public libraries on Facebook in their countries. In the paper some of the results are presented and discussed.

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Mobile phone use among Alcoholics Anonymous members: new sites for recovery

This article reports on a line of research exploring mobile phone use in the recovery efforts of Alcoholics Anonymous (AA) members. A preliminary investigation indicated that many individuals in AA have come to rely on the mobile phone for both instrumental and expressive recovery-related interactions. This article reports on follow-up initiatives to assess whether and how these forms of use are linked to its perceived value and explores more deeply how the technology is used in these ways. Using both quantitative and qualitative approaches, the study found that expressive use of the mobile phone made a particularly meaningful contribution to the perceived value of the technology as a tool for recovery. In addition, it uncovered ways that AA members are using mobile communication for social support and to stay connected with others in the program. The discussion offers implications of the findings and directions for future research.

This document describes the Namespace Identifier (NID) for Uniform ::: Resource Namespace (URN) resources published by the Open Mobile ::: Alliance (OMA). OMA defines and manages resources that utilize this ::: URN name model. Management activities for these and other resource ::: types are provided by the Open Mobile Naming Authority (OMNA). This ::: memo provides information for the Internet community.

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Why Lonely People Get Sick More Often

New research suggests that social isolation alters the immune system at the genetic level, raising the risk of serious disease. Oh, and the definition of loneliness might surprise you.

Researchers are using Facebook habits to study how tastes and values affect the formation of social relationships.

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Study Accuses Belgium of Collaborating

A government-backed report released Tuesday blamed Belgian authorities and the ruling elite for collaborating with the Nazi persecution of Jews during World War II.Comment

Researchers are using Facebook habits to study how tastes and values affect the formation of social relationships.

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Social norms and self-presentation on social network sites: Profile work in action

Unpacking "privacy" for a networked world

Parameter study and design of wide-band widescan dual-polarized tapered slot antenna arrays

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Musical Training as a Framework for Brain Plasticity: Behavior, Function, and Structure

When the brain plays music: auditory–motor interactions in music perception and production

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

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Spectral Efficiency of MIMO Millimeter-Wave Links with Single-Carrier Modulation for 5G Networks

Tractable Model for Rate in Self-Backhauled Millimeter Wave Cellular Networks

The Effect of Social Media on Student ’ s Engagement and Collaboration : a case study of University of Venda using Facebook

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The anatomy of a large-scale social search engine

What do people ask their social networks, and why?: a survey study of status message q&a behavior

Motivations for social networking at work

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Understanding Usages and Affordances of Enterprise Social Networks: A Sociomaterial Perspective

enterprise social media : definition , history , and prospects for the study of social technologies in organizations .

Multidisciplinary optimization of servodrives for robot manipulators

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2 cognitive - behavioral theory .

Virtual Reality Exposure Therapy

data mining and social web semantics : a case study on the use of hashtags and memes in online social networks .

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A comparative study of three social networking websites

MySpace and Facebook: Applying the Uses and Gratifications Theory to Exploring Friend-Networking Sites

m-TSNE: A Framework for Visualizing High-Dimensional Multivariate Time Series

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Image classification using the web graph

Automatic Detection of Human Nudes

"Snapchat is more personal": An exploratory study on Snapchat behaviors and young adult interpersonal relationships

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Teen Study: Social Media Is Positive Experience

A study by the Pew Research Center's Internet and American Life Project reveals what teens think about the online experience. While bullying on social media sites like Facebook gets a lot of news coverage, most teens think social networks are a friendly place for them.

Many school-age kids have long since traded in their rocking horses and jump ropes for digital play. Commentator David Kushner describes why he thinks the Webkinz Web site is preparing children for life in a "virtualized society."

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Credibility and usefulness of health information on Facebook: a survey study with U.S. college students

Perceived usefulness, perceived ease of use, and user acceptance of information technology

Metal-Induced Oxidative Stress and Plant Mitochondria

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The evolution of social ties online: A longitudinal study in a massively multiplayer online game

The Scientific Research Potential of Virtual Worlds

A face(book) in the crowd: social Searching vs. social browsing

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How Envy Influences SNS Intentions to Use

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

it ' s written on your face : detecting affective states from facial expressions while learning computer programming .

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User Migration in Online Social Networks: A Case Study on Reddit During a Period of Community Unrest

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

The Network Paradigm in Organizational Research: A Review and Typology

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" novel aspects coming from the directionality of online relationships : a case study of twitter " by haewoon kwak , changhyun lee , hosung park , hyunwoo chun and sue moon with ching - man au yeung as coordinator .

Too Much of a Good Thing? The Relationship Between Number of Friends and Interpersonal Impressions on Facebook

Bromelain: An Overview

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Links between Adolescents' Deep and Surface Learning Approaches, Problematic Internet Use, and Fear of Missing Out (FoMO)

the moderator - mediator variable distinction in social psychological research : conceptual , strategic , and statistical considerations .

Congenital macrodactyly: a clinical study.

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tourists ' attachment processes and behavioral changes in social media : persuasion and reference group influence perspective .

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

Corneal Higher-order Aberrations and Visual Improvement Following Corneal Transplantation in Treating Herpes Simplex Keratitis.

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Enriching in-person encounters through social media: A study on family connectedness for the elderly

Connection strategies: Social capital implications of Facebook-enabled communication practices

Feature Diagrams and Logics: There and Back Again

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effects on jealousy and relationship happiness .

social capital , self - esteem , and use of online social network sites : a longitudinal analysis .

Genotoxicity assessment of soil contamination: a case study from Farakka coal-fired power plant in eastern India

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The impact of social media use on academic performance among university students: a pilot study

Social networking: Communication revolution or evolution?

A face(book) in the crowd: social Searching vs. social browsing

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Instagram addiction and the Big Five of personality: The mediating role of self-liking

Association between Facebook addiction, self-esteem and life satisfaction: A cross-sectional study

Problematic Use of Social Network Sites: The Interactive Relationship Between Gratifications Sought and Privacy Concerns

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the effect of social network sites on adolescents ' social and academic development : current theories and controversies .

Social Consequences of the Internet for Adolescents: A Decade of Research

Clavibacter michiganensis subsp. michiganensis strains virulence and genetic diversity. a first study in Argentina

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Friending, IMing, and Hanging Out Face-to-Face: Overlap in Adolescents' Online and Offline Social Networks

A longitudinal study of the relation between adolescent boys and girls' computer use with friends and friendship quality: Support for the social compensation or the rich-get-richer hypothesis?

Parameter Sharing Deep Deterministic Policy Gradient for Cooperative Multi-agent Reinforcement Learning

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The effects of technostress and switching stress on discontinued use of social networking services: a study of Facebook use

user acceptance of computer technology : a comparison of two theoretical models * .

Distributed Cooperative Control of DC Microgrids

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is facebook affecting workplace productivity

According to a new survey by work force solutions provider Kelly Services, more than half of workers say social media is negatively affecting workplace productivity, with 57 percent believing that mixing personal and professional connections through social media has the potential to cause problems.he study also shows a number of employees are using their personal social media accounts to talk about company business. Nearly 15 percent of the employees surveyed think it is okay to share opinions about work with friends and colleagues on social media.

There are two effects that I want to talk about. Facebook Has a Negative Impact on the Concentration of Students, about 70-75 percent of high school students are falling behind in class because they spend many hours on Facebook.Therefore, it leads to lack of time to studying or concentration on school work.tudents watch adult movie on Facebook-As Facebook becomes popular, there are more users uploading a lot of music videos that was over 18. The problem is that on Facebook there are many middle school students around 8-9 years old always playing around, so the chance that they would watch adult videos is very high.

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Enriching in-person encounters through social media: A study on family connectedness for the elderly

Connection strategies: Social capital implications of Facebook-enabled communication practices

FromDaDy: Spreading Aircraft Trajectories Across Views to Support Iterative Queries

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Trends in online social networking: adolescent use of MySpace over time

The need to belong: Desire for interpersonal attachments as a fundamental human motivation.

aging changes of the midfacial fat compartments : a computed tomographic study .

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Credibility and usefulness of health information on Facebook: a survey study with U.S. college students

Perceived usefulness, perceived ease of use, and user acceptance of information technology

“Mask-Bot 2i”: An active customisable robotic head with interchangeable face

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Adoption of Social Media and the Quality of Life of Older Adults

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

The perceptions towards mobile services: an empirical analysis of the role of use facilitators

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"Was It Something I Said?" "No, It Was Something You Posted!" A Study of the Spiral of Silence Theory in Social Media Contexts

Social Media Use for News and Individuals' Social Capital, Civic Engagement and Political Participation

Mental health professionals’ attitudes towards mental illness: professional and cultural factors in the INTER NOS study

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Adoption of Social Media and the Quality of Life of Older Adults

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

Direct NMR observation and pKa determination of the Asp102 side chain in a serine protease.

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Analysis of personal information security behavior and awareness

Information revelation and internet privacy concerns on social network sites: a case study of facebook

An Interface Model for Parallel Components

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Studying Organizations on Instagram

Pictures Speak Louder than Words: Motivations for Using Instagram

Cultural difference in motivations for using social network sites: A comparative study of American and Korean college students

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Journal of Personality and Social Psychology: Attitudes and social cognition.

there is nothing so theoretical as a good method .

A comparative study of three social networking websites

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The reciprocal effects of social network site use and the disposition for self-disclosure: A longitudinal study

Social cognitive theory of mass communication

Spectrum sharing scenarios and resulting technical requirements for 5G systems

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average time someone spends on social media

Americans aged 18-64 who use social networks say they spend an average of 3.2 hours per day doing so, according to new research released by Ipsos Open Thinking Exchange (OTX).

The biggest increase has been among young adults, with time spent online almost tripling from 10 hours and 24 minutes each week in 2005 to 27 hours and 36 minutes in 2014. In total, the average adult spends more than 20 hours online a week, which includes time spent on the internet at work. Meanwhile the average person spends 2.5 hours every week “online while on the move” - away from their home, work or place of study. This is a five-fold increase from 2005, when the figure was just 30 minutes.

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A new type of attack on message authentication codes (MACs) is introduced which takes advantage of possible weaknesses in interfaces to hardware security modules. In particular, if a module does not fix the degree of MAC truncation employed, then potentially serious attacks are possible.

Modern trains rely on balises (communication beacons) located on the track to provide location information as they traverse a rail network. Balises, such as those conforming to the Eurobalise standard, were not designed with security in mind and are thus vulnerable to cyber attacks targeting data availability, integrity, or authenticity. In this work, we discuss data integrity threats to balise transmission modules and use high-fidelity simulation to study the risks posed by data integrity attacks. To mitigate such risk, we propose a practical two-layer solution: at the device level, we design a lightweight and low-cost cryptographic solution to protect the integrity of the location information; at the system layer, we devise a secure hybrid train speed controller to mitigate the impact under various attacks. Our simulation results demonstrate the effectiveness of our proposed solutions.

ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system...

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Physical Layer Security in Two-tier Heterogeneous Cellular Networks over Nakagami Channel during Uplink Phase

In this paper, we study the connection and secrecy performance under two-tier cellular network during uplink phase, where both large-scale factor (path propagation loss) and small-scale factor (Nakagami fading) are considered., which are beyond the scope of the existing works. Analytical expressions of network connection and secrecy probabilities are derived., which are validated through Monte Carlo simulations. Numerical results reveal that the theoretical expressions of connection and secrecy probabilities are in good agreement with simulation results. Moreover, simulation results demonstrate that larger $m$ value, which means stronger LOS component, leads to a worse connection performance, but a better secrecy secrecy performance.

This paper studies the secure multiterminal source coding problem with actions. In particular, one main encoder observes an independent and identically distributed (i.i.d.) source Xn and wishes to compress this source lossyly to the decoder. Another encoder observes the source Yn and wants to compress this source losslessly to the decoder. A passive eavesdropper having access to the side information Zn can observe the information bits sent by the main encoder. In this scenario, the decoder is allowed to choose actions affecting the correlated source Yn and the side information Zn. For this problem, we characterize the optimal rate-distortion-cost-leakage region for a discrete memoryless setting.

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An enhanced SOS architecture for DDoS attack defense using active network technology

After a long time study of DDoS attack, we find that the secure overlay services (SOS) architecture is one of the best ways to protect our service. There is no other reason but the ability to provide reliable communication between authorized clients and a protected target under on-going DDoS attacks. The SOS architecture defines a set of overlay nodes, arranged in four function groups, that controls access to the protected target. Although, the architecture is novel and works well under simple congestion based attacks, we observe that when the attacker uses the same malicious traffic raid on the SOS nodes with some kind of sleight, the SOS system cannot respond to this kind of trick and somehow it has already threatened the reliability of the SOS. We propose a scheme to enhance the SOS against intelligent DDoS attacks, both from the mechanisms and the detection algorithm.

In this article we will show you how to carry out the water charging system,used in LAN,including it's main structure,designing conception as well as the key technology to solve several problems we met.We emphasized the way to realize a Client/Server structured MIS based on DB.Finally we will tell you how to carry out this system,which is developed in C++Builder IDE,in detail.

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Activation-Induced Cytidine Deaminase Expression in Gastric Cancer

Helicobacter pylori increases the risk of gastric cancer development and triggers aberrant expression of activation-induced cytidine deaminase (AID). The goal of the present study w

The pervasive usage of the Internet has made secure group communications a significant issue. Conference-key agreement protocols provide secure group communications with lower computational cost. Providing key agreements and updates of dynamic groups in an efficient manner is a significant challenge for conference-key agreement protocols. Auxiliary key agreement operations are needed to solve the challenge. In this paper, we propose an improved conference-key agreement protocol, called Dynamic Conference-Key Agreement Protocol, that consists of Initial Conference-Key Agreement Protocol and Auxiliary Conference-Key Agreement operations. Dynamic Conference-Key Agreement Protocol has operations to handle dynamic groups. The proposed protocol has better fault correction and provides the same security level with the existing ones. Copyright © 2014 John Wiley & Sons, Ltd.

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A Fault Detection Scheme Based on Self-Clustering Nodes Sets for Wireless Sensor Networks

In this paper, we present a fault detection scheme based on self-clustering nodes sets for wireless sensor networks. In WSN, sensors' measurements are spatially related, and fault nodes can be detected by local comparisons. We firstly cluster nodes into several sets by the similarity of nodes' measurements using self-clustering algorithm. Nodes in the several top large-scale sets are mainly credible. Then we set credible nodes' status as healthy, and run the adjacent nodes comparing algorithm. Faulty sensor nodes can be identified by the comparisons between neighbor nodes and dissemination of the decision made at each node. Time redundancy is used to tolerate transient faults in sensing and communication. Simulation results show that the fault detection accuracy is kept high and the false alarm rate is kept low, even when 35% of the sensor nodes are faulty.

We propose a framework for examining trust in the storage stack based on different levels of trustworthiness present across different channels of information flow. We focus on corruption in one of the channels, the data channel and as a case study, we apply type-aware corruption techniques to examine Windows NTFS behavior when on-disk pointers are corrupted. We find that NTFS does not verify on-disk pointers thoroughly before using them and that even established error handling techniques like replication are often used ineffectively. Our study indicates the need to more carefully examine how trust is managed within modern file systems.

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Caravan: Providing location privacy for vanet

An Efficient System for Non-transferable Anonymous Credentials with Optional Anonymity Revocation

A large-scale study of programming languages and code quality in GitHub

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Forensic carving of network packets and associated data structures

End-System Optimizations for High-Speed TCP

remembrance of data passed : a study of disk sanitization practices .

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MILS virtualization for Integrated Modular Avionics

an empirical study into the security exposure to hosts of hostile virtualized environments tavis .

ipv6 over low - power wireless personal area networks ( 6lowpans ) : overview , assumptions , problem statement , and goals .

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A testbed for secure and robust SCADA systems

Security issues in SCADA networks

perineal nodular induration ( " biker ' s nodule " ) : report of two cases with fine - needle aspiration cytology and immunohistochemical study .

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Pileus: protecting user resources from vulnerable cloud services

A lattice model of secure information flow

Comparing VR and non-VR driving simulations: An experimental user study

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Cold Boot Attacks are Still Hot: Security Analysis of Memory Scramblers in Modern Processors

Clearing the clouds: a study of emerging scale-out workloads on modern hardware

Combining visual and acoustic features for audio classification tasks

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Benzoyl Fluorides as Fluorination Reagents: Reconstruction of Acyl Fluorides via Reversible Acyl C–F Bond Cleavage/Formation in Palladium Catalysis

This report describes the formation of value-added acyl fluorides by means of palladium-catalyzed acyl-exchange reactions between acyl fluorides and acid anhydrides. This method allows using a simple and commercially available acyl fluoride, benzoyl fluoride, as the fluoride source for the easy and efficient preparation of a variety of more complex acyl fluorides. The results of this study suggest that this reaction proceeds via a reversible acyl C–F bond cleavage/formation at the palladium center.

In this work we have examined a series of 25 different Fischer carbene complexes of the type (CO)5CrC(X)R with X = H, OH, OCH3, NH2, and NHCH3 and R = H, CH3, CHCH2, Ph, and C⋮CH, to analyze the influence of each substituent on the molecular structure and bonding of these complexes. Energy and charge decomposition analysis of the interaction between the chromium pentacarbonyl and the carbene fragments reveal that for the metal−carbene bond donation is quantitatively more important than back-donation. However, it is the back-donation rather than donation that correlates with most geometrical and electronic parameters of the complexes studied. The reasons for the larger influence of back-donation on the molecular structure of Fischer carbene complexes are discussed.

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Theoretical study of hexaphosphabenzene and its valence isomers. Is cyclic P6 stable

Abstract Ab initio calculations show that the cyclic aromatic structure (hexaphosphabenzene) is a minimum on the P 6 potential energy surface, and is kinetically stable to its unimolecular destruction. In contrast to the N 6 analogue, hexaphosphabenzene lies very close in energy to its valence P 6 isomers. This interesting difference between P 6 and N 6 is analyzed in terms of energy components.

Zinc enolates derived from substituted 1-aryl-2,2-dibromoalkanones react with 3-acetyl-6-bromochromen-2-one to give 1a-acetyl-1-alkyl-1-aroyl-6-bromo-1a,7b-dihydro-1H-cyclopropa[c]chromen-2-ones as a single stereoisomer.

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Morphological study of chain-extended growth in polyethylene: 3. Annealing of solution-grown lamellae

Abstract Solution-grown lamellae of three commercial polyethylenes of differing molecular weight ranges have been annealed on substrates at high pressures. The polymers transform to the new high-pressure phase before melting but the new lamellar thicknesses reached remain much below those found for the bulk material. Electron diffraction patterns support the identification of the new phase as hexagonal and it is concluded that the effects of annealing polyethylene in an unusual context are close to those which would have been produced by local melting followed by rapid recrystallization.

Abstract Asymmetric total synthesis of small ring macrolide stagonolide-E has been described in this communication. The main highlight of our synthetic strategy is the application of ME-DKR (metal enzyme combo dynamic kinetic resolution) reaction, asymmetric reduction with Noyori’s BINAL-H reagent system, stereoselective cross metathesis, and RCM (ring closing metathesis) reaction at a late stage enables us to achieve the synthesis of the target molecule in an efficient way.

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Spectroscopic study of carbenes in low-temperature matrices

The review surveys and gives a systematic account of the literature data on the IR and UV spectroscopic studies on carbenes in low-temperature matrices. The methods of generation and isolation of carbenes in inert matrices at temperatures around 10 K are examined. The possibility of applying the data obtained to the study of the structure of carbenes and to the determination of the mechanisms of reactions involving them is demonstrated. The bibliography includes 67 references.

Chemosensory devices with self organized structures and artificial receptors are developed for a wide field of applications. Supramolecular hosts, highly ordered liquid crystal phases and even Langmuir Blodgett films are promising recognition elements. Cage compounds such as tert- butyl-calix[n]arene show high preorganization due to their rigid walls and form highly symmetrical cavities suitable for host guest inclusion of analytes. Disturbance of the highly ordered cholesteric and nematic phases influences the optical and dielectric properties of these materials.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

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Thienoquinolizidinones. Synthesis and rearrangement into new piperidino[1,2-a][1,3] or [1,4]diazepinones fused to a thiophene ring

A convenient route to thienoquinolizidinones is described starting from ethyl pipecolinate and suitable halogenomethylthiophenes or 3-chloromethylbenzothiophene. The Schmidt reaction and the Beckmann rearrangement of oximes of these ketones led to piperidino[1,2-a] [1,3] or [1,4]diazepines fused to a thiophene ring

The results of comparative kinetic study of the miniemulsion controlled radical polymerization of styrene in the presence of reversible chain transfer agents (benzyl dithiobenzoate and polystyrene dithiobenzoate) and bulk polymerization of similar systems are presented. The influence of the reactant nature and dithiobenzoate concentration of the kinetics of the process is discussed.

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Base-catalyzed isomerization of 3-methyl-3-norcarene epoxides

A study was made of the isomerization of the trans- and cis-3,4-epoxy~3-methylnorcaranes by Et2NLi in ether and t-BuOK in pyridine. The action of both bases on the trans-epoxide gives comparable amounts of 4α-hydroxy-3-methyl-2-norcarene and 3α-hydroxy-3-methyl-4-norcarene. In the reactions of the cis-epoxide the composition of the reaction mixture depends on the employed reagent: in the presence of Et2NLi the main product is 4β-hydroxy-3-methylnorcarane, while with t-BuOK it is 3β-hydroxy-3-methyl-4-norcarene.

A description is given of a paramagnetic center produced in single crystals of iodic acid, HIO3, when irradiated at room temperature with either x or γ rays. This center is interpreted as neutral iodine atoms, I0, trapped in the crystal. ESR studies indicate four different trapping sites that are related by the crystal symmetry. The g values, the hfs tensor, and the quadrupole interaction tensor are presented and discussed.

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Synthesis and properties of novel 9,10-di(naphthalen-2-yl)anthracene derivatives

Abstract Three novel molecules were designed and synthesized based on a known compound 9,10-di(naphthalen-2-yl)anthracene (MADN). To broaden the π-conjugated system, three units with different electronegativity were introduced and connected to the C-2 position of MADN by vinyl unit. The Suzuki reaction, the Wittig reaction, and the Heck reaction were employed to synthesize these compounds. MADN is a well-known anthracene derivative which has been widely used as blue emitter. All these results indicate that these novel MADN derivatives could be some kind of potential materials for OLEDs.

A detailed theoretical study of the mechanism and energetics of an organocatalysis based on C=N activation by halogen-bonding is presented for the hydrocyanation of N-benzylidenemethylamine. The calculations at the level of scalar-relativistic gradient-corrected density functional theory give an insight in this catalytic concept and provide information on the characteristics of four different monodentate catalyst candidates acting as halogen-bond donors during the reaction.

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The Polymerization of Silacyclopentene and -pentane Derivatives

The polymerization of 1,1,3-trimethyl-1-silacyclopentene-3 (I), 1-methyl-, 1-allyl-1,1-diallyl-1-silacyclopentenes and -pentanes with aluminum chloride was carried out. By means of an IR spectroscopic analysis of the resulting polymers, it was established that not only ring opening but also vinyl polymerization due to the C–C double bond occur in this polymerization. Attempts to polymerize I with other catalysts, such as BF3·OEt2, AIBN, KOH, and a Ziegler catalyst, were unsuccessful.

Abstract Both fibroin-based and sericin-based biomaterials have been studying extensively due to their wide applications, however the extraction of either fibroin or sericin protein is extremely complicated. Here we prepare the protein solution directly from alive silkworms instead of extracting proteins from silkworm silk. The protein solution and the polyvinyl alcohol solution are mixed in different weight ratios to produce silkworm-based silk fibers, which have many special properties like high mechanical strength and good wetting property. The new production has potential applications as a new textile fabric or a new bio-inspired material.

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Dynamic 1H NMR spectroscopic study of the restricted SN rotation in aryl-N-(arylsulfonyl)-N-(triphenylphosphoranylidene)imidocarbamates

Abstract Dynamic 1 H NMR (500 MHz) investigation of aryl- N -(arylsulfonyl)- N -(triphenylphosphoranylidene)imidocarbamates in CDCl 3 , CD 3 COCD 3 , and CD 3 OD at the temperature range of 183–298 K is reported. The observed free energy barriers (almost 12 kcal mol −1 ) are attributed to conformational isomerization about the N S bond and these barriers show very little solvent dependence.

New synthetic approaches to the preparation of 2-(trifluoromethyl)indole and 2-amino-3-(trifluoromethyl)quinoline have been developed. In both cases, conditions of the Leimgruber-Batcho synthesis of indoles were used in the key step.

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An expedient synthesis of 3-acyltetramic acids of the melophlin family from α-aminoesters and immobilized Ph3PCCO

Abstract The naturally occurring 3-acyltetramic acids (3-acylpyrrolidine-2,4-diones) melophlin A, B, C and G were prepared in few steps from α-aminoesters or their hydrochlorides by cyclization with Ph 3 PCCO under mild conditions. The employment of immobilized, polystyrene-bound ylide greatly simplifies the removal of by-product Ph 3 PO and of other impurities. Various 3-acylation methods were assessed.

This paper deals with the behaviour of hydrolyse d Polyacrylamide solutions in the presence of chromium III. First, using potentiometry and spectroscopy, we study the complexation between chromium III and sodium acetate used as a low molecular weight model for the polymer. Then the same methods are applied to investigate the polymer—Cr(III) complexation and the results are discussed in conjunction with the nature of the physical states of the systems. Finally, we perform rheological measurements in the sol—gel transition regime in a range where the number of crosslinking points can be calculated unambiguously.

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Efficient construction of the oxatricyclo[6.3.1.0(0,0)]dodecane core of komaroviquinone using a cyclization/cycloaddition cascade of a rhodium carbenoid intermediate.

The rhodium(II)-catalyzed cyclization/cycloaddition cascade of a o-carbomethoxyaryl diazo dione is described as a potential route to the oxatricyclo[6.3.1.0(0,0)]dodecane substructure of the icetexane diterpene komaroviquinone. The initially formed carbonyl ylide dipole prefers to cyclize to an epoxide at 25 degrees C but can be induced to undergo cycloaddition across the tethered pi-bond at higher temperatures. [reaction: see text]

The aim of this paper is first to introduce and study Rota-Baxter cosystems and bisystems as generalization of Rota-Baxter coalgebras and bialgebras, respectively, with various examples. The second purpose is to provide an alternative definition of covariant bialgebras via coderivations. Furthermore, we consider coquasitriangular covariant bialgebras which are generalization of coquasitriangular infinitesimal bialgebras, coassociative Yang-Baxter pairs, coassociative Yang-Baxter equation, double coalgebras and dendriform coalgebras. We study some of their properties and relationships with Rota-Baxter cosystems and bisystems.

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Structure of the blue forms of bisphthalocyanines of rare-earth elements

Using electron spectroscopy, X-ray photoelectron spectroscopy, and ESR spectroscopy, the blue forms of bisphthalocyanines of rare-earth elements were found to have structures of sandwich-type complexes with isoelectronic phthalocyanine ligands linked with tetravalent metal ions, [Pc2−Ln4+Pc2−]0. A comparative spectral and electrochemical study of the blue and green forms oftert-butyl-substituted bisphthalocyanines was carried out for almost the whole series of rare-earth metals. Lutetium octa(perfluoro-tert-butyl)- and perchlorobisphthalocyanines were synthesized for the first time.

Two comparative synthetic routes to new enantiomeric C 2 -symmetric Boc-protected biaziridinyls from tartaric ester were studied. Simplicity, high enantiomeric purity and high chemical yield of the target compound characterize the proposed methods. Also, unprotected biaziridinyl was synthesized and fully characterized.

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Tuning the chemoselective hydrogenation of aromatic ketones, aromatic aldehydes and quinolines catalyzed by phosphine functionalized ionic liquid stabilized ruthenium nanoparticles

Ruthenium nanoparticles (Ru NPs) stabilized by phosphine-functionalized ionic liquids (PFILs) were synthesized in an imidazolium-based ionic liquid using H2 as a reductant. Characterization showed well-dispersed particles of about 2.2 nm (TEM) and confirmed the PFIL stabilization of the Ru NPs (NMR). The Ru NPs stabilized by PFILs exhibited excellent activity and switchable chemoselectivity in the heterogeneous selective hydrogenation of aromatic ketones, aromatic aldehydes and quinolines under mild conditions.

A study was carried out on the separation of active anthraquinone ingredient in Chinese rhubarb using High-Speed Countercurrent Chromatography with acid-base accommodationt. Trifluoroacetic acid (TFA) was used as the retaining acid and ammonia liquor as the eluent base. The solvent system was n-hexane-acetic ester-methanol-water (ratio by volume was 9 ∶1 ∶5 ∶5). The separative product was confirmed as five pure anthraquinone of Chinese rhubarb by High Performance Liquid Chromatography (HPLC).

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1H-NMR study of the inclusion processes for α- and γ-cyclodextrin with fenbufen†

1H-NMR spectra of aqueous solutions of fenbufen and two cyclodextrins (α- or γ-cyclodextrin, respectively) mixtures confirm the formation of an inclusion complex if γ-cyclodextrin is used, whereas in the case of α-cyclodextrin no inclusion complex was obtained. The stoichiometry of the fenbufen/γ-cyclodextrin complex is of the [2:1] type. The geometry of this supramolecular architecture was established through MM+ molecular mechanics calculations. © 2005 Wiley Periodicals, Inc. Biopolymers 77: 361–367, 2005

The compounds reduced are given in the table in order of increasing empirical formulas. Compounds with the same empirical formula are arranged in order of increasing number of rings in the molecule, and compounds with the same number of rings in order of increasing number of substituents. In the case of complex reaction products, the structural formula is given only for that part of the molecule in which changes took place during Birch reduction. Tetrahydrofuran used as an auxiliary solvent is denoted in the table by THF.

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Sc(OTf)3 as Efficient Catalyst for Aryl C-Glycoside Synthesis

s: Sc(OTf) 3 was found to be an efficient catalyst for the C-glycosylation of phenols. Reactions of various functionalized phenols and glycosyl acetates, including an azido-bearing one, are achieved by using a catalytic amount of Sc(OTf) 3 (10 mol % for neutral sugars or 50 mol% for an azido sugar) under mild conditions.

We have used IR spectroscopy to study the reaction between L-cysteine and dimethyl sulfoxide in aqueous medium. We have found that reaction occurs with formation of an insoluble product, which we have identified. We show that oxidation of L-cysteine by dimethyl sulfoxide can occur at an appreciable rate under mild conditions, with formation of L-cystine, dimethyl sulfide, and water.

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Solvent polarity effects on hyperfine couplings of cyclohexadienyl-type radicals

In this study muon-spin rotation (μSR) serves as a tool for sensitive monitoring of the environment of muoniated radicals in isotropic liquids. A systematic investigation of the behaviour of the hyperfine coupling constants of cyclohexadienyl-type radicals is performed, and it is found that they are in linear dependence on solvent polarity, with certain deviations. These deviations are discussed in detail. It is found that with increasing length of the hydroxyalkyl substituent group the perturbation of the phenyl ring becomes smaller.

Polyurethanes are synthesized using three different hydroxyalkylated cardanol–formaldehyde resins, diphenylmethane diisocyanate (MDI), and a commercial polyol (PPG-2000). These polyurethanes are found to be tough and crosslinked. A polyurethane prepared using a higher mole ratio of cardanol/formaldehyde of hydroxyalkylated cardanol–formaldehyde resin is found to possess better thermal and mechanical properties than the polyurethane prepared from a lower mole ratio. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 284–288, 2005

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