bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Semen Study around and Away from Gold Mine Area
Authors: Prasad S.B. , Skandhan K.P. , Sing G.
Published: January 2012

Gold was first detected in human semen in 1981. The entry of gold into semen was hypothesized through food items. Earlier reports identified gold in semen as important for good quality of semen. The infertility rate could be low around gold mine area when compared to other places. The aim of the study was to verify this. Towards this, the quality of human semen around a gold mine (Kolar, India) was evaluated and compared to that from a place which was 2000 km away from a gold mine (Jamnagar, India). A total number of 254 semen samples from Kolar and 437 from Jamnagar were evaluated. The fertility rate was higher in Kolar region. The semen samples studied for both places showed that the semen quality was superior in Kolar gold field area.
Crafting Experience:
Authors: Freeman-Moir John
Published: January 2012

In different yet resonating ways both William Morris and John Dewey turned their attention to utopian experience as everyday making and doing. Dewey developed a holistic analysis of human action that contains intimations of utopia as well as a critique of fractured experience. Morris is well known for his vivid picture of utopia as life lived artfully. Comparisons have been noted between Morris and Dewey but not explored in detail. This article looks at Morris’s view of utopian experience from the perspective of Dewey’s pragmatist understanding of action, habit, and artful experience. It is argued that the craft of experience is an idea central to the utopian thinking of Morris and Dewey.
Identifying Functional Annotation for Noncoding Genomic Sequences
Authors: Mortlock Douglas P. , Pregizer Steven
Published: January 2012

The recent success of genome‐wide association studies has generated a trove of biologically significant variants implicated in human disease. However, many, if not most, of these variants fall in noncoding regions that have traditionally lacked much functional annotation. New data sets and tools allow for a more detailed assessment of potential importance of noncoding genetic variants. An overview of types of regulatory annotation that are currently available, and approaches to analyzing this data are provided with emphasis on usage of the UCSC genome browser. Curr. Protoc. Hum. Genet. 72:1.10.1‐1.10.10 © 2012 by John Wiley & Sons, Inc.
Disliked Music can be Better for Performance than Liked Music
Authors: Perham Nick , Sykora Martinne
Published: January 2012

Although liked music is known to improve performance through boosting one's mood and arousal, both liked music and disliked music impair serial recall performance. Given that the key acoustical feature of this impairment is the acoustical variation, it is possible that some music may contain less acoustical variation and so produce less impairment. In this situation, unliked, unfamiliar music could be better for performance than liked, familiar music. This study tested this by asking participants to serially recall eight‐item lists in either quiet, liked or disliked music conditions. Results showed that performance was significantly poorer in both music conditions compared with quiet. More importantly, performance in the liked music condition was significantly poorer than in the disliked music condition. These findings provide further illustration of the irrelevant sound effect and limitations of the impact of liked music on cognition. Copyright © 2012 John Wiley & Sons, Ltd.
On Homogeneous Gold/Palladium Catalytic Systems
Authors: Hashmi A. Stephen K. , Lothschütz Christian , Döpp René , Ackermann Martin , De Buck Becker Janosc , Rudolph Matthias , Scholz Christian , Rominger Frank
Published: January 2012

Two substrates containing an aryl iodide and an allenoate ester were prepared and the gold‐induced cycloisomerisation to vinylgold(I) species and their proto‐deauration as well as the intramolecular palladium‐catalysed cross‐coupling reactions were investigated. Switching to catalytic amounts of gold and palladium and stoichiometric amounts of silver did indeed furnish the product of a cycloisomerisation/intramolecular cross‐coupling. Control experiments revealed that silver cannot substitute for gold or palladium in these reactions, but a different palladium catalyst in a different oxidation state also afforded the cycloisomerisation/intramolecular cross‐coupling products in only slightly reduced yields. By ICP analysis the palladium was shown to contain gold only at the sub‐ppm level. This shows how carefully results obtained with such systems have to be interpreted. Then a series of allylic and benzylic o‐alkynylbenzoates were investigated in gold‐ and palladium‐catalysed reactions. For esters of benzyl alcohol and cinnamyl alcohol no palladium co‐catalyst was needed for the conversion. All reagents were thoroughly checked for palladium traces by ICP analysis in order to thoroughly exclude a gold/palladium co‐catalysis. Optimisation of the gold complex, counter ion and solvent showed that gold(I) isonitrile pre‐catalysts and silver triflate as activator in dioxane are suitable to convert a number of substrates with aryl, alkyl and even cyclopropyl substituents. Crossover experiments proved an intermolecular allyl transfer.
Application of a Recombinant Escherichia coli Whole‐Cell Catalyst Expressing Hydroxynitrile Lyase and Nitrilase Activities in Ionic Liquids for the Production of (S)‐Mandelic Acid and (S)‐Mandeloamide
Authors: Baum Stefanie , van Rantwijk Fred , Stolz Andreas
Published: January 2012

The conversion of benzaldehyde and cyanide into mandelic acid and mandeloamide by a recombinant Escherichia coli strain which simultaneously expressed an (S)‐hydroxynitrile lyase (oxynitrilase) from cassava (Manihot esculenta) and an arylacetonitrilase from Pseudomonas fluorescens EBC191 was studied. Benzaldehyde exhibited a pronounced inhibitory effect on the nitrilase activity in concentrations ≥25 mM. Therefore, it was tested if two‐phase systems consisting of a buffered aqueous phase and the ionic liquid 1‐butyl‐1‐pyrrolidinium bis(trifluoromethanesulfonyl)imide (BMpl NTf2) or 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMim PF6) could be used for the intended biotransformation. The distribution coefficients of the substrates, intermediates and products of the reaction were determined and it was found that BMpl NTf2 and BMim PF6 were highly efficient as substrate reservoirs for benzaldehyde. The recombinant E. coli strain was active in the presence of BMpl NTf2 or BMim PF6 phases and converted benzaldehyde and cyanide into mandelic acid and mandeloamide. The two‐phase systems allowed the conversion of benzaldehyde dissolved in the ionic liquids to a concentration of 700 mM with product yields (=sum of mandelic acid and mandeloamide) of 87–100%. The cells were slightly more effective in the presence of BMpl NTf2 than in the presence of BMim PF6. In both two‐phase systems benzaldehyde and cyanide were converted into (S)‐mandeloamide and (S)‐mandelic acid with enantiomeric excesses ≥94%. The recombinant E. coli cells formed, in the two‐phase systems with ionic liquids and increased substrate concentrations, higher relative amounts of mandeloamide than in a purely aqueous system with lower substrate concentrations.
Evolutionary Catalyst Screening: Iridium‐Catalyzed Imine Hydrogenation
Authors: Kluwer Alexander M. , Detz Remko J. , Abiri Zohar , van der Burg Alida M. , Reek Joost N. H.
Published: January 2012

A high throughput catalyst screening is presented employing an evolutionary approach. The method comprises the optimization of initial leads by subjecting the catalysts to iterative rounds of optimization, including structural elaboration of the ligands by creating new focused libraries. Highly modular supramolecular ligands, robotized synthesis combined by high throughput experimentation creates a platform for fast catalyst development. An illustrative example for the asymmetric hydrogenation of cyclic 2,3,3‐trimethyl‐3H‐indole using iridium catalysts is presented. The kinetic investigation of the best catalyst yields an unusual second order in iridium, first order in hydrogen and zeroth order in substrate. Under optimized reaction conditions a TOF of 100 mol mol−1 h−1 with 96% ee could be obtained with the best catalyst. A full catalyst screening and kinetic study was conducted within a three‐week time‐frame.
Dimerization of Terminal Arylalkynes in Aqueous Medium by Ruthenium and Acid Promoted (RAP) Catalysis: Acetate‐ Assisted (sp)C(sp2)C Bond Formation
Authors: Coniglio Alessandra , Bassetti Mauro , García‐Garrido Sergio E. , Gimeno José
Published: January 2012

The hexamethylbenzene ruthenium(II) dimer [{RuCl(μ‐Cl)(η6‐C6Me6)}]2 (5 mol%), tested among a series of ruthenium(II) and ruthenium(IV) complexes, represents an efficient precatalyst source for the dimerization of terminal arylalkynes ArCCH [Ar=C6H5, 3,4,5‐(OMe)3C6H2, 4‐MeOC6H4, 2‐MeOC6H4, 4‐MeC6H4, 2,4,5‐Me3C6H2, 4‐BrC6H4, 4‐ClC6H4, 4‐FC6H4, 4‐HC(O)C6H4, 4‐CH2CHC6H4, 3‐NCC6H4, 4‐O2NC6H4, 4‐EtO2C‐(CH2)3OC6H4, 4‐HO(CH2CH2O)3C6H4, 3‐HO(CH2CH2O)3‐C6H4] in acetic acid/water mixture (1:1, v/v). The reactions proceed for 24 h at room temperature under heterogeneous conditions and afford the dimeric enyne derivatives (E)‐ArCHCHCCAr in high yields and stereoselectivity. The preformed acetato complex [RuCl(η6‐C6Me6)(κ2‐OAc)] catalyzes the dimerization of phenylacetylene under analogous conditions, with rapid substrate conversion. The presence of cosolvents of acetic acid different from water reduces dramatically the efficiency and selectivity of the reaction. The aqueous medium facilitates the activation stage of the precatalyst by assisting the splitting of the ruthenium dimer. The addition or generation in situ of acetate salts results in shorter reactions times (0.5–3 h) and excellent yields, due to the rapid formation of active acetato complexes. Circumstantial evidence indicates that the π‐bound alkyne molecule is activated by intramolecular proton abstraction. This is currently the most efficient, E‐selective and wide‐scope catalytic system for the alkyne dimerization reaction in protic aqueous media.
Palladium(II)/Copper Halide/Solvent Combination for Selective Intramolecular Domino Reactions of Indolecarboxylic Acid Allylamides: An Unprecedented Arylation/Esterification Sequence
Authors: Broggini Gianluigi , Barbera Vincenzina , Beccalli Egle M. , Borsini Elena , Galli Simona , Lanza Giuseppe , Zecchi Gaetano
Published: January 2012

Intramolecular oxidative palladium‐catalyzed reactions of indolylallylamides in the presence of the couple bis(acetonitrile) palladium dichloride and copper(II) halide are described. Starting from 2‐ and 3‐indolylallylamides and involving in both cases the C‐3 position of the indole nucleus, variously substituted β‐carbolinones were obtained by arylation/halogenation, arylation/esterification or arylation/carboalkoxylation processes. On the other hand, an unusual aminohalogenation/halogenation sequence performed on 2‐indolylallylamides gave rise to pyrazino[1,2‐a]indole products. The carboesterification process is the result of an unknown path that involves the DMF or DMA used as solvent. The outcome of the reactions of the 3‐indolylallylamides arises from a totally selective 1,2‐migration of the acyl group on the supposed spiro intermediates formed from the nucleophilic attack of the C‐3 indole position.
Kinetic and thermodynamic measurements for the facile property prediction of diels–alder‐conjugated material behavior
Authors: Koehler Kenneth Christopher , Durackova Andrea , Kloxin Christopher J. , Bowman Christopher N.
Published: January 2012

The Diels–Alder (DA) reaction between maleimide and furan moieties possessing various substitutions was performed as a means for developing predictive capabilities for temperature and conversion‐dependent material properties in networks comprised of DA moieties. Using HNMR spectroscopy, the reactions of maleimide‐ and furan‐containing molecules further functionalized with carboxylic acids were monitored to ascertain the impact that substitutional changes had on the thermodynamic and kinetic behavior of the DA reaction. The reaction rate and equilibrium conversion of the furan and maleimide increased when the carboxylic acid functional group directly connected to the furan ring was moved from the two to the three position. When an aliphatic two‐carbon spacer was used, such that the π‐electrons of the carboxylic acid and furan were no longer conjugated, the reaction rate increased further. We also report the reactivity effect on the distance between the carboxylic acid functional group and the maleimide, which yielded little impact on the reaction rate but exhibited increased equilibrium conversion with increasing distance. Additionally, the impact on the kinetic and thermodynamic properties of coupling the carboxylic acid to another molecule, tert‐butyl glycine, was also determined. When the carboxylic acid was coupled to an amine, the DA reaction between the furan and maleimide was generally found to have similar kinetic and thermodynamic behavior as compared to their uncoupled, carboxylic acid equivalents. Thus, the characterized and tabulated kinetic and thermodynamic data presented herein enables the prediction of a broad set of temperature‐dependent chemical and material properties. Finally, we discuss practical limitations and nuances of the DA reaction, such as the potential for the maleimide to ring‐open in aqueous media via hydrolysis. © 2012 American Institute of Chemical Engineers AIChE J, 2012
Identification of nonlinear parameter varying systems with missing output data
Authors: Deng Jing , Huang Biao
Published: January 2012

An identification of nonlinear parameter varying systems using particle filter under the framework of the expectation‐maximizaiton (EM) algorithm is described. In chemical industries, processes are often designed to perform tasks under various operating conditions. To circumvent the modeling difficulties rendered by multiple operating conditions and the transitions between different working points, the EM algorithm, which iteratively increases the likelihood function, is applied. Meanwhile the missing output data problem which is common in real industry is also considered in this work. Particle filters are adopted to deal with the computation of expectation functions. The efficiency of the proposed method is illustrated through simulated examples and a pilot‐scale experiment. © 2012 American Institute of Chemical Engineers AIChE J, 2012
Elastic liquid jet impaction on a high‐speed moving surface
Authors: Keshavarz B. , Green S. I. , Eadie D. T.
Published: January 2012

In the railroad industry a friction‐modifying non‐Newtonian liquid, showing elastic behavior, may be applied to the rail in the form of a liquid jet. The interaction of this elastic liquid jet and the moving surface—specifically whether it splashes or adheres without splash—is important in this industrial application. Twelve different elastic liquids with widely varying relaxation times were tested to isolate the effect of elasticity from other fluid properties. Using high‐speed imaging, the interaction between the impinging jet and the moving surface could be captured and analyzed. Although similar to Newtonian jets, for which the Reynolds number plays a major role, the Deborah number was also salient to the splash of elastic liquids. At the elevated Weber numbers of the testing, the Weber number had a much smaller impact on splash than did the Reynolds or Deborah numbers. The ratio of the surface velocity to the jet velocity has only a small effect on the splash. © 2012 American Institute of Chemical Engineers AIChE J, 2012
Flame spray pyrolysis synthesis and aerosol deposition of nanoparticle films
Authors: Tricoli Antonio , Elmøe Tobias D.
Published: January 2012

The assembly of nanoparticle films by flame spray pyrolysis (FSP) synthesis and deposition on temperature‐controlled substrates (323–723 K) was investigated for several application‐relevant conditions. An exemplary SnO2 nanoparticle aerosol was generated by FSP and its properties (e.g., particle size distribution), and deposition dynamics were studied in details aiming to a simple correlation between process settings and film growth rate. At high precursor concentrations (0.05–0.5·mol/L), typically used for FSP synthesis, the nanoparticles agglomerated rapidly in the aerosol leading to large (>100 nm) fractal‐like structures with low diffusivity. As a result, thermophoresis was confirmed as the dominant nanoparticle deposition mechanism down to small (≈40 K) temperature differences (ΔT) between the aerosol and the substrate surface. For moderate‐high ΔT (>120 K), thermal equilibrium was rapidly obtained yielding a constant thermophoretic flux and film growth rate. A model was developed to predict the nanoparticle deposition rates by FSP synthesis at moderate‐high ΔT that does not require detailed analysis of the aerosol composition. Comparison with previous studies having similar nozzle geometries showed that the deposition rates of FSP‐made aerosols can be reasonably well predicted for various materials and flame conditions. © 2012 American Institute of Chemical Engineers AIChE J, 2012
Inaccuracy of self‐reported low sodium diet
Authors: Gerber Linda M. , Mann Samuel J.
Published: January 2012

Objectives:

This study evaluates how often the self‐report of a low sodium (Na) intake is reflected by a low 24‐h urinary sodium excretion and examines the influence of incomplete urinary collections on this comparison.

Methods:

In a study in which 24‐h urine collections were obtained for measurement of Na and creatinine excretion, 120 participants were asked whether their Na intake was low, medium, or high. A 24‐h urine collection was considered complete if creatinine excretion was ≥20 mg/kg in men or ≥15 mg/kg in women, and incomplete if below those amounts. The kappa statistic was computed to assess the level of agreement between 24‐h Na excretion, dichotomized at 100 meq and self‐report responses.

Results:

Agreement between self‐reported and actual Na excretion was poor. The kappa statistic was 0.18 for the total sample, 0.04 for complete collectors, and 0.51 for incomplete collectors, respectively. Overall, 24‐h Na excretion exceeded 100 meq among 75% of those reporting an average or high Na intake, but it also exceeded 100 meq among 57% of those reporting a low sodium intake. Further, among those reporting a low sodium intake, Na excretion exceeded 100 meq in 80% of those who submitted a complete collection, but in only 29% of those who submitted an incomplete collection.

Conclusions:

These findings suggest that many individuals who report a low salt diet actually excrete ≥100 meq/day. Na intake is also frequently underestimated because many 24‐h urine collections are incomplete. Am. J. Hum. Biol., 2012. © 2012 Wiley Periodicals, Inc.
Synthesis and characterization of diethanolamine‐containing glass ionomer cement
Authors: Yang Xin , Ma Guiping , Nie Jun
Published: January 2012

In this study, glycidyl methacrylate (GMA) diethanolamine was synthesized and incorporated into polyacid main chains, which would be used for glass ionomer cements (GICs). The polymer was prepared by the free radical polymerization of acrylic acid and itaconic acid with readily synthesized GMA diethanolamine. Effects of molecular weight, polymer content in the liquid composition, powder/liquid ratio, and aging on compressive strength and diametral tensile strength were investigated. Working and setting time, water sorption and solubility (Wsl), pH value of the immersed solution, and microhardness were also measured. The experimental GICs had comparable mechanical properties to Fuji II GICs while exhibiting less Wsl and high hydrophilicity. The results suggested that the experimental GICs held promise as biocompatible and workable cement for application. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of PEG‐graft‐quaternized chitosan and cationic polymeric liposomes for drug delivery
Authors: Liang Xiaofei , Sun Yanming , Duan Yourong , Cheng Yingsheng
Published: January 2012

Poly(ethylene glycol) grafted octadecyl quaternized carboxymethyl chitosan (PEG‐g‐OQC) copolymers were synthesized to both improve the biocompatibility of OQC and form PEGylated cationic polymeric liposomes (CPLs), which composed of the mixture of OQC, cholesterol, and PEG‐g‐OQC. Structure of the copolymers was characterized by using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H‐NMR), and X‐ray diffraction (XRD). The methyl tetrazolium (MTT) assay with L929 cell lines confirmed that PEGylation can decrease the cytotoxicity of OQC. PEGylated CPL nanoparticles (NPs) can be prepared by adding different weight ratio of PEG‐g‐OQC in the mixture. Paclitaxel was successfully incorporated into PEGylated CPLs with high drug encapsulating efficiency (>90%) and drug loading capacity (>15%). Physical stability experiment showed that paclitaxel‐loaded PEGylated CPLs was stable with little change of particle size and size distribution in the condition of freeze‐dried by adding mannitol or in high temperature and high pressure. Power or reagent of drug‐loaded PEGylated CPLs showed a slow steady release profile for paclitaxel. These results show that PEG‐g‐OQC and CPLs have potential application as a drug delivery vehicle. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
A green, chemoselective, and efficient protocol for Paal–Knorr pyrrole and bispyrrole synthesis using biodegradable polymeric catalyst PEG‐SO3H in water
Authors: Ali Jafari Abbas , Amini Sakineh , Tamaddon Fatemah
Published: January 2012

In water and in the presence of 1 mol % of Poly(ethylene glycol)‐bounded sulfonic acid, amines undergo smooth condensation with 2,5‐hexadione at room temperature to afford the corresponding pyrroles in good to excellent yields. The sole products were solidified as the reaction proceeded and separated by simple filtration. In addition, bispyrroles were synthesized in excellent yields via this eco‐friendly protocol. The method is easy, simple, cost‐effective, chemoselective, and environmentally benign that introduces a beautiful example of click chemistry in water. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Where do the progenitors of millisecond pulsars come from?
Authors: Taani A. , Zhang C.M. , Al‐Wardat M. , Zhao Y.H.
Published: January 2012

Observations of a large population of millisecond pulsars (MSPs) show a wide divergence in the orbital periods (from approximately hours to a few months). In the standard view, low‐mass X‐ray binaries (LMXBs) are considered as progenitors for some MSPs during the recycling process. We present a systematic study that combines different types of compact objects in binaries such as cataclysmic variables (CVs), LMXBs, and MSPs. We plot them together in the so called Corbet diagram. Larger and different samples are needed to better constrain the result as a function of the environment and formations. A scale diagram showing the distribution of MSPs for different orbital periods and the aspects for their progenitors relying on accretion induced collapse (AIC) of white dwarfs in binaries. Thus massive CVs (M ≥ 1.1 M⊙) can play a vital role on binary evolution, as well as of the physical processes involved in the formation and evolution of neutron stars and their magnetic fields, and could turn into binary MSPs with different scales of orbital periods; this effect can be explained by the AIC process. This scenario also suggests that some fraction of isolated MSPs in the Galactic disk could be formed through the same channel, forming the contribution of some CVs to the single‐degenerate progenitors of Type Ia supernova. Furthermore, we have refined the statistical distribution and evolution by using updated data. This implies that the significant studies of compact objects in binary systems can benefit from the Corbet diagram.Observations of a large population of millisecond pulsars (MSPs) show a wide divergence in the orbital periods (from approximately hours to a few months). In the standard view, low‐mass X‐ray binaries (LMXBs) are considered as progenitors for some MSPs during the recycling process. We present a systematic study that combines different types of compact objects in binaries such as cataclysmic variables (CVs), LMXBs, and MSPs. We plot them together in the so called Corbet diagram. Larger and different samples are needed to better constrain the result as a function of the environment and formations. A scale diagram showing the distribution of MSPs for different orbital periods and the aspects for their progenitors re
Verification of Reynolds stress parameterizations from simulations
Authors: Snellman J.E. , Brandenburg A. , Käpylä P.J. , Mantere M.J.
Published: January 2012

We determine the timescales associated with turbulent decay and isotropization in closure models using anisotropically forced and freely decaying turbulence simulations and study the applicability of these models. We compare the results from anisotropically forced three‐dimensional numerical simulations with the predictions of the closure models and obtain the turbulent timescales mentioned above as functions of the Reynolds number. In a second set of simulations, turning the forcing off enables us to study the validity of the closures in freely decaying turbulence. Both types of experiments suggest that the timescale of turbulent decay converges to a constant value at higher Reynolds numbers. Furthermore, the relative importance of isotropization is found to be about 2.5 times larger at higher Reynolds numbers than in the more viscous regime (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Deep sequencing study of the MTHFR gene to identify variants associated with myelomeningocele
Authors: Aneji Chiamaka N. , Northrup Hope , Sing Au Kit
Published: January 2012

INTRODUCTION: Neural tube defects (NTDs) are congenital anomalies caused by a combination of genetic and environmental influences. A defect below the head region resulting in protuberance of meninges and nervous tissue is termed myelomeningocele (MM). MM, the most common NTD compatible with survival, occurs in approximately 1 in 1000 births worldwide. Maternal preconceptional and periconceptional folate supplementation reduces the risk of NTDs by up to 70%. A key enzyme in folate metabolism is 5, 10‐methylene‐tetrahydrofolate reductase (MTHFR). OBJECTIVES: Sequence the 12 exons of the MTHFR gene among 96 subjects with MM to identify variants potentially contributing to the disease trait. METHODS: Exons were amplified by polymerase chain reaction, and the products were sequenced with the Sanger method to reveal sequence variants compared to MTHFR reference sequences. Association of variants was examined by Fisher's test. RESULTS: A novel variant c.171+3G>T was identified in intron 1 in one affected subject. The variant was not found in the subject's unaffected mother's DNA, and the unaffected father's DNA was unavailable. We found significant differences in allele frequencies for seven SNPs in MM subjects compared with ethnically matched reference populations reported in the single nucleotide polymorphism database. CONCLUSION: We identified a novel variant c.171+3G>T in the MTHFR gene that potentially affects splicing in an affected subject. In addition, we observed five SNPs (rs13306561, rs2274976, rs2066462, rs12121543, and rs1476413) in the MTHFR gene not previously shown to associate with MM. The current study provides additional evidence that multiple variations in the MTHFR gene are associated with MM. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Scavenging of hydroxyl radical by catecholamines
Authors: Kładna Aleksandra , Berczyński Paweł , Kruk Irena , Michalska Teresa , Aboul‐Enein Hassan Y.
Published: January 2012

The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH•) and hydroxyl radial (HO•). The CATs examined were found to inhibit the ESR signal intensity of DPPH• in a dose‐dependent manner over the range 0.1–2.5 mmol/L in the following order: NA > A > I > D, with IC50 = 0.30 ± 0.03 for noradrenaline and IC50 = 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5‐dimethyl‐1‐pyrroline N‐oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (kr) of CATs with HO• were found to be in the order of 109 L/mol/s, and the kr value for noradrenaline was the highest (kr = 8.4 × 109 L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62–73% at 1 mmol/L concentration and 79–89% at 2 mmol/L concentration) from a Fenton‐like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. Copyright © 2012 John Wiley & Sons, Ltd.
Distinct structural and optical regimes in natural silk spinning
Authors: Holland Chris , O'Neil Kathy , Vollrath Fritz , Dicko Cedric
Published: January 2012

This study investigates the relationship between birefringence and mechanical properties in the dragline silk of the gold orb weaving spider Nephila edulis. Using a custom birefringence‐tensile testing device, we probed the orientation and water‐induced swelling of fibers spun at variety of drawing rates ranging from 0.003 to 400 mm s−1. Our results indicate that based upon drawing rate, silk fibers fall into three distinct regimes each with characteristic orientation and swelling properties. Further investigation using in situ tensile testing reveals interactions between a fiber's drawing speed, mechanical properties, and orientation that support previous model predictions. We propose that simultaneous birefringence‐tensile testing provides a unique and readily accessible insight into the structural behavior of this interesting and important biomaterial. © 2011 Wiley Periodicals, Inc. Biopolymers 97: 368–373, 2012.
Critical polyelectrolyte adsorption under confinement: Planar slit, cylindrical pore, and spherical cavity
Authors: Cherstvy A. G.
Published: January 2012

We explore the properties of adsorption of flexible polyelectrolyte chains in confined spaces between the oppositely charged surfaces in three basic geometries. A method of approximate uniformly valid solutions for the Green function equation for the eigenfunctions of polymer density distributions is developed to rationalize the critical adsorption conditions. The same approach was implemented in our recent study for the “inverse” problem of polyelectrolyte adsorption onto a planar surface, and on the outer surface of rod‐like and spherical obstacles. For the three adsorption geometries investigated, the theory yields simple scaling relations for the minimal surface charge density that triggers the chain adsorption, as a function of the Debye screening length and surface curvature. The encapsulation of polyelectrolytes is governed by interplay of the electrostatic attraction energy toward the adsorbing surface and entropic repulsion of the chain squeezed into a thin slit or small cavities. Under the conditions of surface‐mediated confinement, substantially larger polymer linear charge densities are required to adsorb a polyelectrolyte inside a charged spherical cavity, relative to a cylindrical pore and to a planar slit (at the same interfacial surface charge density). Possible biological implications are discussed briefly in the end. © 2012 Wiley Periodicals, Inc. Biopolymers 97: 311–317, 2012.
Systematic review and meta-analysis of the effect of North American working hours restrictions on mortality and morbidity in surgical patients
Authors: Jamal M H , Doi S A R , Rousseau M , Edwards M , Rao C , Barendregt J J , Snell L , Meterissian S
Published: January 2012

Background

Short duty hours, imposed by the Accreditation Council of Graduate Medical Education (ACGME) regulations, have been claimed to be associated with loss of continuity of care among surgical patients, leading to a potentially increased risk of adverse surgical outcomes. This systematic review and meta-analysis assessed the strength of associations between duty hour restrictions and morbidity and mortality of various surgical procedures.

Methods

MEDLINE, Embase, BIOSIS Previews®, the Education Resources Information Center and the Cochrane Central Register of Controlled Trials (January 2000 to September 2009) were searched, and reports screened to identify comparative studies of mortality and morbidity before and after the introduction of ACGME regulation periods. Random-effects (RE) and quality-effects (QE) meta-analyses were performed to determine the risk of morbidity or death associated with long duty hours compared with shorter duty hours. Results are presented as odds ratio (OR) with 95 per cent confidence interval.

Results

A total of 19 data sets (10 articles), including 730 648 subjects in the mortality studies and 64 346 in the morbidity studies, were analysed. Long duty hours were associated with a non-significantly increased risk of death compared with shorter duty hours (OR 1·28, 0·94 to 1·73). There was no difference in morbidity between the two groups (OR 1·03, 0·67 to 1·57). Mortality associations were generally stronger for general surgery, more recent studies and higher-quality studies. Heterogeneity was evident among the studies included.

Conclusion

The reduction in working hours has not affected patient care negatively in terms of demonstrable differences in morbidity and mortality. However, it cannot be distinguished whether this effect is actually due to a non-detrimental effect of the reduction in working hours or whether any such detriment is offset by continually improving patient care and increased surgical supervision.
Superficially porous particles columns for super fast HPLC separations
Authors: Ali Imran , AL‐Othman Zeid A. , Al‐Za'abi Mohammed
Published: January 2012

Superficially porous silica particles columns (SPSPCs) are manufactured by different companies. The most common have the brand names Halo, Ascentis Express and Kinetex. These columns provide super fast, sharp peaks and moderate sample loading and back pressure. These are available in different chemistries such as C8, C18, RP Amide and Hilic. Normally, the silica gel particles have 2.7 and 1.7 µm total and inner solid core diameters with 0.5 µm thick outer porous layer, 90 Å pore size and 150 m2/g surface area. They have been used for the separation and identification of low and high molecular weight compounds. The present article describes the state of the art of superficially porous silica particles based columns with special emphasis on their structures, mechanisms of separation, applications and comparison. Copyright © 2012 John Wiley & Sons, Ltd.
Information flow control of component‐based distributed systems
Authors: Sfaxi Lilia , Abdellatif Takoua , Robbana Riadh , Lakhnech Yassine
Published: January 2012

Noninterference is a strong security policy that enforces confidentiality and integrity. Many solutions are proposed in the state of the art for verifying this policy in programs, but few tools are proposed to implement it. In this paper, we define a high‐level model called Component Information Flow, and we develop the tools that simplify distributed secure system development and deployment.

The developer focuses on developing the functional part of his or her system and defines his or her system security properties by using a high‐level configuration. When this configuration is validated, that is, no security leak is detected, the system security code is generated. To validate and demonstrate the effectiveness of our approach, we apply the Component Information Flow tools to a classical Web service use case. Copyright © 2012 John Wiley & Sons, Ltd.
The color of langatate crystals and its relationship with composition and optical properties
Authors: Kuz'micheva G. M. , Kaurova I. A. , Rybakov V. B. , Khasanov S. S. , Cousson A. , Zaharko O. , Domoroschina E. N. , Dubovsky A. B.
Published: January 2012

Langatate crystals grown by the Czochralski method in 〈0001〉 and 〈01$ \bar 1 $1〉 directions both without subsequent annealing (from colorless to orange crystals) and with vacuum (colorless and pale‐green crystals) and air (orange crystal) annealing have been investigated by neutron diffraction, X‐ray diffraction and optical spectroscopy. The main types of point defects were compared with absorption bands: oxygen vacancies ‐ VO•• (0.35‐0.36 µm), the vacancies in the lanthanum position ‐ VLa‴ (0.29‐0.30 µm); the absorption band at 0.48‐0.49 µm is typical for the colored samples. The relationship between the X color coordinate (red component) and the oxygen contents has been obtained. The green color of the sample annealed in vacuum is due to the presence of Ta+3 ions in the La(Ta3+,Ga)O3 phase that has the structural and geometric agreement with langatate structure. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
More tractable average error rate expression for the Nth best relay selection scheme of DF relaying over Rayleigh fading channels
Authors: Ko K. , Woo C.
Published: January 2012

In this paper, we derive another exact average error rate expression for the Nth best decode‐and‐forward relay systems over Rayleigh fading channels. On the basis of error‐events at relay nodes, the Nth best relay's selection probability is expressed as a more tractable form in which the number of summations and the length of each summation are specified. Then, exact average error performance metrics are obtained as two well‐known forms. The first is expressed with a moment generating function, and the other is presented as a closed form. Simulation results are finally presented to validate that the derived analytical expression can be a general frame work covering all Rayleigh fading channel conditions. Copyright © 2012 John Wiley & Sons, Ltd.
Synthetic Studies of Sesquiterpenes with the Dunniane Skeleton
Authors: Parés Sònia , Alibés Ramon , Figueredo Marta , Font Josep , Parella Teodor
Published: January 2012

The first synthetic approach to the entire carbon skeleton of the sesquiterpenes dunniane and cumacrene has been developed. The sequence features a [2+2] photochemical reaction of a chiral 2(5H)‐furanone with ethylene to form the cyclobutane, a Meyer–Schuster‐type rearrangement of an α‐acetylenic alcohol to an α,β‐unsaturated aldehyde, and a microwave‐assisted Diels–Alder reaction of an elaborated dienamine with methyl acrylate to construct the six‐membered ring with the desired 1,4‐substitution pattern.
Bayesian Methods for Ion Selective Electrodes
Authors: Dillingham Peter W. , Radu Tanja , Diamond Dermot , Radu Aleksandar , McGraw Christina M.
Published: January 2012

With the increasing use of ion‐selective electrodes in environmental and health applications, it is important to know the precision of estimated concentrations. A Bayesian model for non‐linear calibration is introduced which provides estimates of measurement precision by incorporating uncertainty in calibration parameters and inherent random noise in emf response. The analysis of lead in 17 soil samples demonstrates that large gains in precision are possible when calibrations are extended to include multiple electrodes and standard addition data. The results highlight the need for improved calibration and routine use of standard addition as ion selective electrodes become increasingly popular for demanding, real world applications.
Dehydrogenase‐Based Reagentless Biosensors: Electrochemically Assisted Deposition of Sol‐Gel Thin Films on Functionalized Carbon Nanotubes
Authors: Wang Zhijie , Etienne Mathieu , Pöller Sascha , Schuhmann Wolfgang , Kohring Gert‐Wieland , Mamane Victor , Walcarius Alain
Published: January 2012

Multiwalled carbon nanotubes (MWCNT) have been functionalized, for the electrocatalytic detection of NADH, by microwave treatment, electrochemical deposition of poly(methylene green) or wrapping with an Os‐complex modified polymer. Sol‐gel thin films have been then electrodeposited on the carbon nanotube layers for co‐immobilization of D‐sorbitol dehydrogenase and diaphorase when necessary and NAD+ via covalent linkage using glycidoxypropyltrimethoxysilane. The comparison of these systems shows that the electrodeposited sol‐gel matrix can significantly affect the operational behavior of functionalized MWCNT. Only MWCNT wrapped with the Os‐complex modified polymer and covered with a sol‐gel biocomposite allowed the electrochemical detection of D‐sorbitol in a reagentless configuration.
ITO Electrode Modified by α‐K6[P2W18O62] Hybrid Nanofibers for Nitrite Determination
Authors: Cao Fei , Guo Shu , Ma Huiyan , Gong Jian
Published: January 2012

A promising nitrite sensor based on one‐dimensional polyoxometalate hybrid nanofibers was prepared and developed by electrospinning of a mixture of poly(vinyl alcohol) and α‐K6[P2W18O62]⋅14H2O (P2W18) onto the surface of an indium tin oxide (ITO) electrode. After thermal crosslinking, the P2W18 hybrid nanofibers are insoluble in aqueous solutions even after a period of 24 hours, which ensures the electrochemical stability of the P2W18 hybrid nanofiber‐modified ITO electrode. The cyclic voltammetry results have demonstrated that the P2W18 hybrid nanofiber‐modified ITO electrode exhibits excellent electrocatalytic activity toward the reduction of nitrite in acidic solutions. Additionally, long‐term stability and reproducibility have been observed.
ON THE USES OF ROUTINE PATIENT‐REPORTED HEALTH OUTCOME DATA
Authors: Smith Peter C. , Street Andrew D.
Published: January 2012

It has long been standard practice to ask patients in clinical trials about their health status, but the practice is now being extended to patients receiving treatment on a routine basis. In this paper, we examine four types of analyses that these health data might inform: comparisons of alternative treatments for the same condition, of health care providers, of changes in performance over time and of treatments of different types of condition. Analytical challenges arise because counterfactuals cannot be observed and because health status cannot be measured continuously. The implications of these challenges and the ability to meet them vary according to the comparative exercise. We argue that, provided with a sufficient number of health status measures for each patient and proper risk adjustment, health status measurement has great potential to inform the first three types of comparison. However, we believe that it is not yet possible to use such data to make secure comparative judgements about the outcomes from treatment for different types of condition. Copyright © 2012 John Wiley & Sons, Ltd.
Chemokine Cxcl9 attenuates liver fibrosis-associated angiogenesis in mice
Authors: Sahin Hacer , Borkham-Kamphorst Erawan , Kuppe Christoph , Zaldivar Mirko Moreno , Grouls Christoph , Al-samman Muhammad , Nellen Andreas , Schmitz Petra , Heinrichs Daniel , Berres Marie-Luise , Doleschel Dennis , Scholten David , Weiskirchen Ralf , Moeller Marcus J. , Kiessling Fabian , Trautwein Christian , Wasmuth Hermann E.
Published: January 2012

Recent data suggest that the chemokine receptor CXCR3 is functionally involved in fibroproliferative disorders, including liver fibrosis. Neoangiogenesis is an important pathophysiological feature of liver scarring, but a functional role of angiostatic CXCR3 chemokines in this process is unclear. We therefore investigated neoangiogenesis in carbon tetrachloride (CCl4)-induced liver fibrosis in

Cxcr3

−/− and wildtype mice by histological, molecular, and functional imaging methods. Furthermore, we assessed the direct role of vascular endothelial growth factor (VEGF) overexpression on liver angiogenesis and the fibroproliferative response using a Tet-inducible bitransgenic mouse model. The feasibility of attenuation of angiogenesis and associated liver fibrosis by therapeutic treatment with the angiostatic chemokine Cxcl9 was systematically analyzed

in vitro

and

in vivo

. The results demonstrate that fibrosis progression in

Cxcr3

−/− mice was strongly linked to enhanced neoangiogenesis and VEGF/VEGFR2 expression compared with wildtype littermates. Systemic VEGF overexpression led to a fibrogenic response within the liver and was associated with a significantly increased Cxcl9 expression.

In vitro

, Cxcl9 displayed strong antiproliferative and antimigratory effects on VEGF-stimulated endothelial cells and stellate cells by way of reduced VEGFR2 (KDR), phospholipase Cγ (PLCγ), and extracellular signal-regulated kinase (ERK) phosphorylation, identifying this chemokine as a direct counter-regulatory molecule of VEGF signaling within the liver. Accordingly, systemic administration of Cxcl9 led to a strong attenuation of neoangiogenesis and experimental liver fibrosis

in vivo

.

Conclusion:

The results identify direct angiostatic and antifibrotic effects of the Cxcr3 ligand Cxcl9 in a model of experimental liver fibrosis. The amelioration of liver damage by systemic application of Cxcl9 might offer a novel therapeutic approach for chronic liver diseases associated with increased neoangiogenesis. (Hepatology 2012)
The Developmental Origin of Metacognition
Authors: Brinck Ingar , Liljenfors Rikard
Published: January 2012

We explain metacognition as a management of cognitive resources that does not necessitate algorithmic strategies or metarepresentation. When pragmatic, world‐directed actions cannot reduce the distance to the goal, agents engage in epistemic action directed at cognition. Such actions often are physical and involve other people, and so are open to observation. Taking a dynamic systems approach to development, we suggest that implicit and perceptual metacognition emerges from dyadic reciprocal interaction. Early intersubjectivity allows infants to internalize and construct rudimentary strategies for monitoring and control of their own and others' cognitions by emotion and attention. The functions of initiating, maintaining, and achieving turns make proto‐conversation a productive platform for developing metacognition. It enables caregiver and infant to create shared routines for epistemic actions that permit training of metacognitive skills. The adult is of double epistemic use to the infant—as a teacher that comments on and corrects the infant's efforts, and as the infant's cognitive resource in its own right. Copyright © 2012 John Wiley & Sons, Ltd.
The mitochondrial permeability transition pore provides a key to the diagnosis and treatment of traumatic brain injury
Authors: Veech Richard L. , Valeri C. Robert , VanItallie Theodore B.
Published: January 2012

The pathological consequences of traumatic head injury result largely from the opening of the mitochondrial permeability transition pore (mPTP). The mPTP opens due to a decrease in brain phosphorylation energy resulting in a further decrease in brain ATP production and a measurable increase in brain heat generation and temperature. The increase in brain temperature can be measured transcranially by near infrared spectroscopy which can be used to diagnose traumatic brain injury (TBI) and to monitor treatment. Effective therapy of TBI can be achieved by closure of the mPTP by administration of cyclosporine A or by oral administration of ketone body esters. While ketosis has previously been known to prevent damage from TBI, the availability of oral ketone esters presents the first practical modality of achieving therapeutic levels of ketone bodies. © 2012 IUBMB Life, 2012