bluuebunny/crossref_metadata_2025_split huggingface dataset:
Verification of Reynolds stress parameterizations from simulations
Authors: Snellman J.E. , Brandenburg A. , Käpylä P.J. , Mantere M.J. 
Published: January 2012

AbstractWe 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

AbstractINTRODUCTION: 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

ABSTRACTThe 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

AbstractThis 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

AbstractWe 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

Abstract

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

ABSTRACTSuperficially 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

SUMMARYNoninterference 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

AbstractLangatate 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

SUMMARYIn 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

AbstractThe 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

AbstractWith 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

AbstractMultiwalled 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

AbstractA 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

ABSTRACTIt 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

Abstract

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 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

AbstractThe 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
Increased new bone formation with a surface magnesium‐incorporated deproteinized porcine bone substitute in rabbit calvarial defects
Authors: Park Jin‐Woo , Ko Hyuk‐Jin , Jang Je‐Hee , Kang Hochang , Suh Jo‐Young 
Published: January 2012

AbstractThis study investigated the effects of magnesium ion (Mg) incorporation into the surface of deproteinized porcine cancellous bone in the bone healing of rabbit calvarial defects with the expectation of utilizing the integrin–ligand binding enhancement effect of Mg, and compared its bone healing capacity with that of untreated porcine cancellous bone and deproteinized bovine bone (Bio‐Oss). Hydrothermal treatment was performed to produce Mg‐incorporated porcine bone using an alkaline Mg‐containing solution. The surface morphology and chemical composition of the samples were investigated using scanning electron microscopy, energy‐dispersive X‐ray spectrometry, and X‐ray photoelectron spectroscopy. Defects 7 mm in diameter were created in the calvaria of 14 adult male New Zealand White rabbits and were filled with (1) untreated porcine bone (PB), (2) Bio‐Oss, and (3) Mg‐containing porcine bone (MG). The percentage of newly formed bone (NB%) was evaluated histomorphometrically at 2 and 4 weeks after implantation. Hydrothermal treatment resulted in a Mg‐containing surface in porcine bone covered with nanostructures ∼100 nm in size. The MG group supported better new bone formation compared with the other groups. Osteoconductive new bone formation was observed in the central defect area in the MG group at an early healing time‐point. Histomorphometric analysis revealed significantly greater NB% in the MG group when compared with the untreated PB and Bio‐Oss groups at 4 weeks (p < 0.05). The Mg‐incorporated porcine bone with surface nanostructures achieved rapid new bone formation in the osseous defects of rabbit calvaria compared with untreated xenografts of porcine and bovine origin. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.