bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proteins with Highly Similar Native Folds Can Show Vastly Dissimilar Folding Behavior When Desolvated
Authors: Schennach Moritz , Breuker Kathrin 
Published: November 2013

AbstractProteins can be exposed to vastly different environments such as the cytosol or membranes, but the delicate balance between external factors and intrinsic determinants of protein structure, stability, and folding is only poorly understood. Here we used electron capture dissociation to study horse and tuna heart Cytochromes c in the complete absence of solvent. The significantly different stability of their highly similar native folds after transfer into the gas phase, and their strikingly different folding behavior in the gas phase, can be rationalized on the basis of electrostatic interactions such as salt bridges. In the absence of hydrophobic bonding, protein folding is far slower and more complex than in solution.
Absorption, metabolism, and excretion of fermented orange juice (poly)phenols in rats
Authors: Escudero‐López Blanca , Calani Luca , Fernández‐Pachón María‐Soledad , Ortega Ángeles , Brighenti Furio , Crozier Alan , Del Rio Daniele 
Published: November 2013

AbstractTwo milliliters of a fermented, pasteurized orange juice containing ∼1% alcohol and 2.3 μmol of (poly)phenolic compounds was fed to rats by gavage after which plasma and urine collected over a 36 h period were analyzed by UHPLC‐mass spectrometry. The main constituents in the juice were hesperetin and naringenin‐O‐glycosides, apigenin‐6,8‐C‐diglucoside, and ferulic acid‐4′‐O‐glucoside. Plasma contained seven flavanone glucuronides, with the principal metabolites, naringenin‐7‐O‐glucuronide, naringenin‐4′‐O‐glucuronide, and an isosakuranetin‐O‐glucuronide, peaking 6 h after intake at concentrations of ∼10 nmol/L. Urinary excretion of four hesperetin glucuronides was equivalent to 0.28% of intake while that of the two naringenin glucuronides was 2.8% of intake. The plasma and urine data suggest that while some absorption occurred in the small intestine, the main site of uptake was the colon. Urine also contained dihydroferulic acid‐4'‐O‐glucuronide and dihydroferulic acid‐4′‐O‐sulfate which were excreted in quantities corresponding to 48.2% of the ingested ferulic acid‐4′‐glucoside. This indicates that the hydroxycinnamate is much more bioavailable than the flavanones in the rat model. Conversion of the ferulic acid glucoside to the dihydroferulic acid metabolites involves the action of colonic microbial glycosidases and reductases/hydrogenases followed by postabsorption phase II metabolism before renal excretion. © 2013 BioFactors, 40(3):327–335, 2014
The single‐crystal NMR experiment: An experimentalist's guide: Part II: Data analysis and assignment of symmetry‐related tensors
Authors: Kennedy Michael A. , Ellis Paul D. 
Published: November 2013

AbstractExplicit expressions needed for the extraction of the chemical shielding tensor from the angle‐dependent chemical shifts are derived for orthogonal and off‐angle probe experiments. Assignment of symmetry‐related chemical shielding tensors via 1) a semi‐empirical method and 2) angle‐dependent line‐widths due to heteronuclear dipolar couplings are discussed.
Phase Transition for the Speed of the Biased Random Walk on the Supercritical Percolation Cluster
Authors: Fribergh Alexander , Hammond Alan 
Published: November 2013

We prove the sharpness of the phase transition for the speed in biased random walk on the supercritical percolation cluster on ℤd. That is, for each d ≥ 2, and for any supercritical parameter p > pc, we prove the existence of a critical strength for the bias such that below this value the speed is positive, and above the value it is zero. We identify the value of the critical bias explicitly, and in the subballistic regime, we find the polynomial order of the distance moved by the particle. Each of these conclusions is obtained by investigating the geometry of the traps that are most effective at delaying the walk.A key element in proving our results is to understand that, on large scales, the particle trajectory is essentially one‐dimensional; we prove such a dynamic renormalization statement in a much stronger form than was previously known. © 2013 Wiley Periodicals, Inc.
Epithelial invasion outcompetes hypha development during Candida albicans infection as revealed by an image‐based systems biology approach
Authors: Mech Franziska , Wilson Duncan , Lehnert Teresa , Hube Bernhard , Thilo Figge Marc 
Published: November 2013

AbstractCandida albicans is the most common opportunistic fungal pathogen of the human mucosal flora, frequently causing infections. The fungus is responsible for invasive infections in immunocompromised patients that can lead to sepsis. The yeast to hypha transition and invasion of host‐tissue represent major determinants in the switch from benign colonizer to invasive pathogen. A comprehensive understanding of the infection process requires analyses at the quantitative level. Utilizing fluorescence microscopy with differential staining, we obtained images of C. albicans undergoing epithelial invasion during a time course of 6 h. An image‐based systems biology approach, combining image analysis and mathematical modeling, was applied to quantify the kinetics of hyphae development, hyphal elongation, and epithelial invasion. The automated image analysis facilitates high‐throughput screening and provided quantities that allow for the time‐resolved characterization of the morphological and invasive state of fungal cells. The interpretation of these data was supported by two mathematical models, a kinetic growth model and a kinetic transition model, that were developed using differential equations. The kinetic growth model describes the increase in hyphal length and revealed that hyphae undergo mass invasion of epithelial cells following primary hypha formation. We also provide evidence that epithelial cells stimulate the production of secondary hyphae by C. albicans. Based on the kinetic transition model, the route of invasion was quantified in the state space of non‐invasive and invasive fungal cells depending on their number of hyphae. This analysis revealed that the initiation of hyphae formation represents an ultimate commitment to invasive growth and suggests that in vivo, the yeast to hypha transition must be under exquisitely tight negative regulation to avoid the transition from commensal to pathogen invading the epithelium. © 2013 International Society for Advancement of Cytometry
Phenotypic divergence in reproductive traits of a moth population experiencing a phenological shift
Authors: Santos Helena M. , Paiva Maria‐Rosa , Rocha Susana , Kerdelhué Carole , Branco Manuela 
Published: November 2013

AbstractAllochrony that is reproductive isolation by time may further lead to divergence of reproductive adaptive traits in response to different environmental pressures over time. A unique “summer” population of the pine processionary moth Thaumetopoea pityocampa, reproductively isolated from the typical winter populations by allochronic differentiation, is here analyzed. This allochronically shifted population reproduces in the spring and develops in the summer, whereas “winter” populations reproduce in the late summer and have winter larval development. Both summer and winter populations coexist in the same pine stands, yet they face different climatic pressures as their active stages are present in different seasons. The occurrence of significant differences between the reproductive traits of the summer population and the typical winter populations (either sympatric or allopatric) is thus hypothesized. Female fecundity, egg size, egg covering, and egg parasitism were analyzed showing that the egg load was lower and that egg size was higher in the summer population than in all the studied winter populations. The scales that cover the egg batches of T. pityocampa differed significantly between populations in shape and color, resulting in a looser and darker covering in the summer population. The single specialist egg parasitoid species of this moth was almost missing in the summer population, and the overall parasitism rates were lower than in the winter population. Results suggest the occurrence of phenotypic differentiation between the summer population and the typical T. pityocampa winter populations for the life‐history traits studied. This work provides an insight into how ecological divergence may follow the process of allochronic reproductive isolation.
Nanoscaled Bismuth Oxido Clusters: Probing Factors of Structure Formation and Photocatalytic Activity
Authors: Schlesinger Maik , Weber Marcus , Rüffer Tobias , Lang Heinrich , Mehring Michael 
Published: November 2013

AbstractHydrolysis of bismuth(III) nitrate in the presence of sodium benzoate (NaOBz) in dimethyl sulfoxide (DMSO) gave the bismuth oxido cluster [{Bi38O45(NO3)20(OBz)4(DMSO)24}·4DMSO][{Bi38O45(NO3)24(DMSO)26}·4DMSO] (1), which crystallizes in the monoclinic space group P21/c with cell parameters of a = 35.8728(12) Å, b = 20.2750(5) Å, c = 34.8624(11) Å, and β = 111.797(4)°. The asymmetric unit contains two crystallographically independent bismuth oxido clusters of different composition. Because of the distinct structural relationship of this type of bismuth oxido clusters with the photocatalytically active polymorph β‐Bi2O3, colloidal suspensions of nanoscaled 1 as well as colloids composed of the recently reported clusters [Bi6O4(OH)4(NO3)6]·H2O (2), [{Bi38O45(NO3)24(DMSO)26}·2DMSO][{Bi38O45(NO3)24(DMSO)24}·0.5DMSO] (3), and [Bi38O45(OMc)24(DMSO)9]·2DMSO·7H2O (4) were probed for their photocatalytic activity. The bismuth oxido cluster 3 decomposes more than 85 % of a 1 × 10–5 M aqueous solution of rhodamine B (RhB) under visible‐light irradiation within 150 min. Colloids of such clusters might serve as model compounds for indirect photodegradation processes of organic contaminants at the metal oxide surface.
The interactive effects of chytrid fungus, pesticides, and exposure timing on gray treefrog (Hyla versicolor) larvae
Authors: Hanlon Shane M. , Parris Matthew J. 
Published: November 2013

Abstract

Aquatic organisms are often exposed to a wide variety of perturbations in nature, including pathogens and chemical contaminants. Despite the co-occurrence of these 2 stressors, few studies have examined the effects of chemical contaminants on host–pathogen dynamics. The authors tested the individual and combined effects on gray treefrog (Hyla versicolor) tadpoles of 2 commonly used pesticides (Roundup® and Sevin®) and the pathogenic fungus Batrachochytrium dendrobatidis (Bd). A fully factorial design was used, and tadpoles were exposed to Bd, Roundup, or Sevin alone, or a combination of Bd and either pesticide at 3 points during larval development (early, mid, late). It was predicted that pesticides would mediate the effect of Bd on tadpoles and reduce the likelihood of negative consequences of infection and that timing of exposure would influence these effects. Tadpoles exposed to Bd at the mid point experienced higher survival through metamorphosis than those exposed to Bd at the early or late points, while tadpoles exposed to Sevin at the early point experienced reduced survival compared with those exposed to Roundup or no-pesticide control at the same exposure point. Roundup ameliorated the effects of Bd on survival compared with tadpoles exposed to Bd alone, while there was no interactive effect of Sevin on survival. In addition, Sevin reduced mass of new metamorphs compared with Roundup and reduced snout–vent length compared with all other treatments. The present study supports the hypothesis that pesticides can mitigate the effects of Bd on amphibian hosts and that such effects may depend on the timing of exposure. Environ Toxicol Chem 2014;33:216–222. © 2013 SETAC
A protocol for metering data pseudonymization in smart grids
Authors: Rottondi Cristina , Mauri Giulia , Verticale Giacomo 
Published: November 2013

AbstractA tradeoff between data collection needs and user privacy is of paramount importance in the Smart Grid. This paper proposes a pseudonymization protocol for data gathered by the Smart Metres, which relies on a network infrastructure and a dedicated set of nodes, called privacy preserving nodes. The network privacy is enforced by a separation of duties; the privacy preserving nodes perform data pseudonymization without having access to the measurements, which are masked by means of a secret sharing scheme, while the entities accessing the data recover and relate the plain measurements generated by the same metre along a time window of finite duration but have no access to the metre identities. The paper also provides an evaluation of the security and of the performance of the protocol, comparing it to the two alternative encryption techniques, which mask the measurements by means of the Chaum mixing scheme or of an identity‐based proxy re‐encryption scheme. Copyright © 2013 John Wiley & Sons, Ltd.
The role of small cell technology in future Smart City applications
Authors: Cimmino Antonio , Pecorella Tommaso , Fantacci Romano , Granelli Fabrizio , Rahman Talha Faizur , Sacchi Claudio , Carlini Camillo , Harsh Piyush 
Published: November 2013

ABSTRACTMeeting citizens’ requirements economically and efficiently is the most important objective of Smart Cities. As a matter of fact, they are considered a key concept both for future Internet and information and communications technology. It is expected that a wide range of services will be made available for residential users (e.g. intelligent transportation systems, e‐government, e‐banking, e‐commerce and smart management of energy demand), public administration entities, public safety and civil protection agencies and so on with increased quality, lower costs and reduced environmental impact. In order to achieve these ambitious objectives, new technologies should be developed such as non‐invasive sensing, highly parallel processing, smart grids and mobile broadband communications. This paper considers the communication aspects of Smart City applications, specifically, the role of the latest developments of Long‐Term Evolution‐Advanced standard, which forecast the increase of broadband coverage by means of small cells. We shall demonstrate that the novel concept of small cell fully meets the emerging communication and networking requirements of future Smart Cities. To this aim, a feasible network architecture for future Smart Cities, based on small cells, will be discussed in the framework of a future smarter and user‐centric perspective of forthcoming 4G mobile technologies. Copyright © 2013 John Wiley & Sons, Ltd.
7‐Halogeno‐2‐Vinylfluorenes and Related Compounds
Authors: Berkovic S. 
Published: November 2013

AbstractAcetylation of 2‐fluoro and 2‐chlorofluorene attacks the 7‐position. Thus, 2‐fluoro‐, 2‐chloro‐ and also 2‐bromo‐7‐vinylfluorene have been prepared. Analogously 4‐fluoro‐and 4‐bromo‐1‐vinylnaphthalene have been synthesized.
A Study on Salmonella Asparaginase
Authors: Kott Y. 
Published: November 2013

Abstractα‐N‐methyl DL‐asparagine was rapidly hydrolyzed by Sal. carmel and Sal. hadar preparations. Higher alkyl derivatives were not hydrolyzed and inhibited L‐asparagine hydrolysis.N (β DL‐aspartyl) methyl amine was not attacked by the enzymatic preparations and inhibited competitively the hydrolysis of L‐asparagine. Similarly, higher β‐N‐alkyl derivatives of asparagine were not hydrolyzed and inhibited L‐asparagine hydrolysis, although to a less extent. D‐asparagine was not hydrolyzed and inhibited competitively the cleavage of L‐asparagine.Zn+ +, Mg+ +, Cu+ + inhibited the enzyme action, while Br−, Cl−, I−, NO3− had no influence on L‐asparagine hydrolysis.
Synthesis of DL‐o‐Trimethylsilyl Phenylalanine
Authors: Gertner D. , Shenhar A. , Zilkha A. 
Published: November 2013

AbstractDL‐o‐Trimethylsilyl phenylalanine was prepared by condensation of o‐trimethylsilyl benzylbromide with diethylformamidomalonate, followed by mild hydrolysis, decarboxylation and deformylation. Its N‐carboxyanhydride was obtained on reaction of the amino acid with phosgene and was polymerized.
The Iodination of Borazines
Authors: Muszkat K.A. , Kirson B. 
Published: November 2013

AbstractN‐Trimethyl‐ and N‐triphenylborazines were iodinated by elemental iodine giving B‐mono‐, B‐di‐ and B‐triiodo‐N‐trimethylborazines and B‐mono‐ and B‐di‐iodo‐N‐triphenylborazines. Borazine itself, however, yields on iodination a non‐volatile product whose structure is discussed. A possible mechanism for the iodination reaction is considered. The charge transfer complex of N‐triphenylborazine and iodine is described.
Polar Effects in the Homoallylic Rearrangement of Arylcyclopropylcarbinols
Authors: Sarel S. , Breuer E. , Ertag Sh. , Salamon R. 
Published: November 2013

AbstractThe synthesis of some p‐substituted phenylmethylcyclopropylcarbinols of the structure (I) is herein reported. Dehydration of the cyclopropylcarbinols by means of acetic anhydride yielded mixtures of α‐cyclopropylstyrenes (V) and 4‐arylpent‐3‐enyl acetates (VI) the ratio of which depended on both the polar characteristics of the substituent X and on reaction conditions. The relative order of the effect of substitution in the phenyl group on V/VI ratio is Cl > H > CH3 > OCH3. The data presented being interpreted in terms of stability of the cyclopropylbenzylium ions (III). The more stable carbonium ions (III or IV) would favor the formation of rearranged products (VI) whereas the less stable would favor the production of V.
Separation of Lithium by Ion Exchange Chromatography
Authors: Ratner R. , Ludmer Z. 
Published: November 2013

AbstractSmall amounts of lithium were separated from large amounts of sodium, potassium, calcium and magnesium ions. The separation was performed by a cation exchange chromatographic method. Amberlite IR‐120 was used as cation exchanger and a mixture of methanol (9 volumes)‐hydrochloric acid (1 volume) was employed as eluent. The separation was quantitative, lithium was eluted first and the effluents containing lithium were free from other cations. In the effluent, lithium was determined by a flame photometric procedure.
4‐Fluoroindole and Derivatives
Authors: Bentov M. , Pelchowicz Z. , Levy A. 
Published: November 2013

Abstract4‐Fluoroindole(VIII) has been prepared by a five‐step synthesis from 2‐fluoro‐6‐nitrotoluene (III). (VIII) has been converted into a number of N,N‐dialkylated 4‐fluorotryptamines.
Synthesis of 5‐and 6‐Halogenoindoles from Indoline
Authors: Ikan R. , Hoffmann E. , Bergmann E. D. , Galun A. 
Published: November 2013

AbstractFor the preparation of 5‐ and 6‐chloro‐ and ‐fluoro‐indoles, methods based on the nitration of indoline have been elaborated.
Spot Test Differentiation of o‐Cresol and 1‐Naphthol from their Isomers
Authors: Feigl F. , Yariv S. 
Published: November 2013

AbstractThe differentiation of o‐cresol and 1‐naphthol from their isomers can be based on their behavior towards ceric salts and the extractibility with ether of the colored reaction products formed. The pertinent spot test procedures are described.
Specific and Sensitive Reactions with the Aid of Montmorillonite II: Pyrocatechol and its Derivatives
Authors: Yariv S. , Bodenheimer W. 
Published: November 2013

AbstractNon chelated phenolic complexes with Fe(III) which are known to form in aqueous solution are not sorbed on montmorillonite. Pyrocatechol which does form a chelate with Fe(III) is absorbed and can therefore be identified in the presence of isomers. Other aromatic compounds with two hydroxy groups in ortho position and esters and ethers of pyrocatechol and its derivatives have also been studied. A sensitive and selective spot test for the identification of pyrocatechol and its derivatives has been worked out.
Organometallic‐Clay Complexes. Part V. Fe(III)‐Pyrocatechol
Authors: Yariv S. , Bodenheimer W. , Heller L. 
Published: November 2013

AbstractThe simultaneous sorption of Fe(III) and pyrocatechol by montmorillonite from aqueous solution at various pH values and the sorption of pyrocatechol by Fe(III) saturated montmorillonite was investigated by chemical and differential thermal analysis and by X‐ray methods. It was inferred that a cationic complex is formed in interlamellar space with an Fe(III): pyrocatechol ratio of 1:1. This differs from the anionic 1:2 and 1:3 complexes previously isolated in the solid state.
Structural Relationship Between Two Polymorphic Forms of β‐Naphthol
Authors: Coppens P. , Heairfield I. 
Published: November 2013

AbstractThe metastable modification of β‐naphthol is shown to be isomorphous with naphthalene. This implies that its crystal structure is disordered, the center of symmetry being statistical. The structures of the metastable and the stable form are rather similar but the phase transformation requires a 180° rotation of about half of the molecules in the crystal.
A Quick and Precise Heterometric Microdetermination of Vanadium with 5,7‐Dibromo‐8‐Hydroxyquinoline
Authors: Bobtelsky M. , Gancz M. 
Published: November 2013

AbstractA heterometric study was made of the reaction between vanadium and 5,7‐dibromo‐8‐hydroxy‐quinolin. A method is presented for the determination of 0.2 mg V+5 in 20 ml aqueous solution which can be carried out within 10 minutes. The analysed solution may generally contain over 95 mol % Ca, Mg, Zn, Ni, Co, Cd, Cr, NaCl, NH4NO3, (NH4)2SO4, citrate, arsenate and tartrate, and over 70 mol % A1, Pb, U, Zr, Th.The error is about 1%
Spectrochemical Determination of Boron and Strontium in Reactor Waters
Authors: Schoenfeld I. 
Published: November 2013

AbstractAn adaptation of the copper spark excitation method of spectrochemical analysis is presented for the determination of boron and strontium in reactor waters. The Intensities of the analytical lines BII‐3451.41A and SrII‐4077.714A were determined photometrically and related to the concentrations of B and Sr.The method covers the ranges 5 × 10−7 to 7.5 × 10−6% and 2.5 × 10−7 to 5 × 10−6% for B and Sr respectively. The method was extended to lower concentrations by five superimposed exposures (the limits of detection then being 10−7% for B and 5 × 10−8% for Sr), and it can be extended even further, when necessary, by use of a greater concentration factor and/or mote superimposed exposures. The method is simple and rapid, and yet adequately sensitive and precise. The coefficients of variation for single determinations of B and St content are about 10% and 14% respectively.
The Preparation and Properties of Some Halomethylpyrimidines
Authors: Ashani Y. , Cohen S. 
Published: November 2013

AbstractHalogen reactivity in various 5‐halomethylpyrimidines is ascribed to mesomeric electron transfer from the ring to the halomethyl group. In the more stable 6‐halomethylpyrimidines, electron abstraction from the ring is of an inductive nature. These effects are reflected in differences in the dissociation constants of corresponding members of the two series.
Reactivators of Inhibited Acetylcholinesterase. I. the Preparation and Properties of 4‐Hydroxyminomethyl‐1‐Methylpyrimidinium Iodide
Authors: Ashani Y. , Edery H. , Zahavy J. , Künberg W. , Cohen Sasson 
Published: November 2013

Abstract4‐Hydroximinomethyl‐pyrimidine (VIII) has been prepared from 4‐methylpyrimidine (III) by nitrosation or, more preferably, by the Ortoleva‐King procedure. The oxime VIII has a syn configuration and yields, upon alkylation with iodomethane, 4‐hydroximinomethyl‐1‐methyl‐pyrimidinium iodide (IX). The latter proved to be a reactivator of phosphorylated acetylcholine esterase in vitro. In combination with low doses of atropine it also protected mice against organophosphate intoxication.