bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of chelating polymer sorbents by using the S methodology
Authors: Pestov Alexander V. , Slepukhin Pavel A. , Yatluk Yury G. , Charushin Valery N. , Chupakhin Oleg N.
Published: January 2012

The article describes a new synthetic approach to modify the structure of phenol‐formaldehyde and resorcinol‐formaldehyde resins, which enables one to functionalize a polymer matrix by using the S (nucleophilic aromatic substitution of hydrogen) methodology. Direct heteroarylation of phenol (resorcinol) fragments in polymer chains with 1,2,4‐triazine derivatives illustrates a new synthetic method in the polymer chemistry. The feature of this methodology is that it provides an opportunity to accomplish direct one‐pot polymer transformations by incorporating of rather complicated chelating groups through the displacement of hydrogen in phenol moieties. It has been shown that in order to obtain chemically modified polymers on the basis of phenol‐formaldehyde and resorcinol‐formaldehyde resins with a high degree of substitution with chelating units, a polymer matrix has to react with 3‐(pyridin‐2′‐yl)‐1,2,4‐triazin‐5(2H)‐one. Also, it has been found that polymer sorbents with a high selectivity can be obtained by using the template method. Targeted synthesis of model compounds, as structural units of the chelating polymers, and elucidation of the structure of their complexes with copper (II) ions have shown that the most plausible type of coordination is formation of the bridge 1 : 1 complexes of the α,α′‐bipyridinyl type. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Artificial neural networks modeling of electrospinning of polyethylene oxide from aqueous acid acetic solution
Authors: Mirzaei Esmaeil , Amani Amir , Sarkar Saeed , Saber Reza , Mohammadyani Dariush , Faridi‐Majidi Reza
Published: January 2012

The artificial neural networks (ANNs) were used to provide a model for investigating the relationships of the electrospinning parameters with the diameter of polyethylene oxide (PEO) nanofibers from acid acetic aqueous solution. The effects of four parameters including PEO concentration, acetic acid concentration, applied voltage, and temperature of the electrospinning media on the nanofibers mean diameter were investigated. To train, test, and valid the model, three datasets of the input variables with random values were prepared and the mean diameters obtained were taken as the output for the network. The datasets were analyzed by ANNs software and the correlation coefficient, R‐squared (R2), between the predicted values of the nanofibers mean diameter and actual amount were obtained. The results demonstrate the capability of the ANNs model for predicting the nanofibers diameter. The 3‐D plots generated from the model show complex and nonlinear relationships between the parameters and nanofibers diameter. From the model, increasing the PEO concentration above a critical point leads to a sharp increase in the nanofibers mean diameter. The effects of applied voltage and temperature are mainly dependent on the PEO concentration. The acetic acid concentration, in general shows a direct relation with the nanofibers mean diameter. The plots also show that to produce nanofibers with the lowest diameter, both the PEO concentration and AcOH concentration should be at lowest values regardless the applied voltage and temperature. In contrast, highest nanofibers diameters are obtained when the PEO concentration and AcOH concentration are at their high values. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Efficient expression of the anti‐AahI' scorpion toxin nanobody under a new functional form in a Pichia pastoris system
Authors: Ezzine Aymen , M'Hirsi el Adab Sonia , Bouhaouala‐Zahar Balkiss , Hmila Issam , Baciou Laura , Marzouki Mohamed Najib
Published: January 2012

Most large‐scale microbial production of recombinant proteins are based on Escherichia coli, yeasts, or filamentous fungi systems. Using eukaryotic hosts, antibody fragments are generally expressed by targeting to the secretory pathway. This enables not only efficient disulfide bond formation but also secretion of soluble and correctly folded product. For this goal, a recombinant vector was constructed to produce a single‐domain antibody (NbAahI′22) directed against AahI′ scorpion toxin using the methylotrophic yeast Pichia pastoris. The corresponding complementary DNA was cloned under control of the alcohol oxidase promoter in frame with the Saccharomyces α‐factor secretion signal and then transferred to P. pastoris cell strain X‐33. Using Western blot, we detected the expression of the recombinant NbAahI′22 exclusively in the culture medium. Targeting to the histidine label, the secreted nanobody was easily purified on nickel–nitrilotriacetic acid resin and then tested in enzyme‐linked immunosorbent assay. Interestingly, the production level of the NbAahI′22 in its new glycosylated form reached more than sixfold that obtained in E. coli. These findings give more evidence for the utilization of P. pastoris as a heterologous expression system.
Working towards a risk prediction model for neural tube defects
Authors: Agopian A.J. , Lupo Philip J. , Tinker Sarah C. , Canfield Mark A. , Mitchell Laura E. ,   and the National Birth Defects Prevention Study
Published: January 2012

BACKGROUND Several risk factors have been consistently associated with neural tube defects (NTDs). However, the predictive ability of these risk factors in combination has not been evaluated. METHODS To assess the predictive ability of established risk factors for NTDs, we built predictive models using data from the National Birth Defects Prevention Study, which is a large, population‐based study of nonsyndromic birth defects. Cases with spina bifida or anencephaly, or both (n = 1239), and controls (n = 8494) were randomly divided into separate training (75% of cases and controls) and validation (remaining 25%) samples. Multivariable logistic regression models were constructed with the training samples. The predictive ability of these models was evaluated in the validation samples by assessing the area under the receiver operator characteristic curves. An ordinal predictive risk index was also constructed and evaluated. In addition, the ability of classification and regression tree (CART) analysis to identify subgroups of women at increased risk for NTDs in offspring was evaluated. RESULTSThe predictive ability of the multivariable models was poor (area under the receiver operating curve: 0.55 for spina bifida only, 0.59 for anencephaly only, and 0.56 for anencephaly and spina bifida combined). The predictive abilities of the ordinal risk indexes and CART models were also low. CONCLUSION Current established risk factors for NTDs are insufficient for population‐level prediction of a women's risk for having affected offspring. Identification of genetic risk factors and novel nongenetic risk factors will be critical to establishing models, with good predictive ability, for NTDs. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Agreement between self‐report and prescription data in medical records for pregnant women
Authors: Sarangarm Preeyaporn , Young Bonnie , Rayburn William , Jaiswal Pallavi , Dodd Melanie , Phelan Sharon , Bakhireva Ludmila
Published: January 2012

BACKGROUND Clinical teratology studies often rely on patient reports of medication use in pregnancy with or without other sources of information. Electronic medical records (EMRs), administrative databases, pharmacy dispensing records, drug registries, and patients' self‐reports are all widely used sources of information to assess potential teratogenic effect of medications. The objective of this study was to assess comparability of self‐reported and prescription medication data in EMRs for the most common therapeutic classes. METHODS The study population included 404 pregnant women prospectively recruited from five prenatal care clinics affiliated with the University of New Mexico. Self‐reported information on prescription medications taken since the last menstrual period (LMP) was obtained by semistructured interviews in either English or Spanish. For validation purposes, EMRs were reviewed to abstract information on medications prescribed between the LMP and the date of the interview. Agreement was estimated by calculating a kappa (κ) coefficient, sensitivity, and specificity. RESULTS In this sample of socially‐disadvantaged (i.e., 67.9% high school education or less, 48.5% no health insurance), predominantly Latina (80.4%) pregnant women, antibiotics and antidiabetic agents were the most prevalent therapeutic classes. The agreement between the two sources substantially varied by therapeutic class, with the highest level of agreement seen among antidiabetic and thyroid medications (κ ≥0.8) and the lowest among opioid analgesics (κ = 0.35). CONCLUSIONS Results indicate a high concordance between self‐report and prescription data for therapeutic classes used chronically, while poor agreement was observed for medications used intermittently, on an 'as needed” basis, or in short courses. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
High‐throughput method for the analysis of venlafaxine in pharmaceutical formulations and biological fluids, using a tris(2,2′‐bipyridyl) ruthenium(II)–peroxydisulphate chemiluminescence system in a two‐chip device
Authors: Al Lawati Haider A. J. , Varma Gouri B. , Suliman Fakhr Eldin O.
Published: January 2012

A simple, rapid and sensitive chemiluminescent (CL) method for the assay of venlafaxine (VEN) in pharmaceutical formulations and serum samples by a two‐chip device is proposed. The method is based on the reaction of this drug with a tris(2,2′‐bipyridyl) ruthenium(II)–peroxydisulphate CL system. The optimum chemical conditions for CL emission were investigated. The calibration graph was linear for the concentration range 0.02–8.0 µg/mL. The detection and quantification limits were found to be 0.006 and 0.018 µg/mL, respectively, while the relative standard deviation (RSD) was <2.0%. The present CL procedure was applied to the determination of VEN in pharmaceutical formulations and serum samples; the recovery levels were in the range 96.5–101.2%. The results suggest that the method is unaffected by the presence of common formulation excipients found in these samples. Copyright © 2012 John Wiley & Sons, Ltd.
Dual effects of phloretin on aflatoxin B1 metabolism: Activation and detoxification of aflatoxin B1
Authors: Gao Shang Shang , Chen Xiao Yan , Zhu Ri Zhe , Choi Byung‐Min , Kim Sun Jun , Kim Bok‐Ryang
Published: January 2012

Typically, chemopreventive agents involve either induction of phase II detoxifying enzymes and/or inhibition of cytochrome P450 enzymes (CYPs) that are required for the activation of procarcinogens. In this study, we investigated the protective effects of phloretin against aflatoxin B1 (AFB1) activation to the ultimate carcinogenic intermediate, AFB1‐8, 9‐epoxide (AFBO), and its subsequent detoxification. Phloretin markedly inhibited formation of the epoxide with human liver microsomes in a dose‐dependent manner. Phloretin also inhibited the activities of nifedipine oxidation and ethoxyresorufin O‐deethylase (EROD) in human liver microsomes. These data show that phloretin strongly inhibits CYP1A2 and CYP3A4 activities, which are involved in the activation of AFB1. Phloretin increased glutathione S‐transferase (GST) activity of alpha mouse liver 12 (AML 12) cells in a dose‐dependent manner. GST activity toward AFBO in cell lysates treated with 20 μM phloretin was 23‐fold that of untreated control cell lysates. The expression of GSTA3, GSTA4, GSTM1, GSTP1 and GSTT1 was induced by phloretin in a dose‐dependent manner in AML 12 cells. GSTP1, GSTM1, and GSTT1 were able to significantly increase the conjugation of AFBO with glutathione. Concurrently, induction of the GST isozyme genes was partially associated with the Nrf2/ARE pathway. Taken together, the results demonstrate that phloretin has a strong chemopreventive effect against AFB1 through its inhibitory effect on CYP1A2, CYP3A4, and its inductive effect on GST activity.
Use of high‐gradient magnetic fishing for reducing proteolysis during fermentation
Authors: Maury Trine L. , Ottow Kim E. , Brask Jesper , Villadsen John , Hobley Timothy J.
Published: January 2012

Proteolysis during fermentation may have a severe impact on the yield and quality of a secreted product. In the current study, we demonstrate the use of high‐gradient magnetic fishing (HGMF) as an efficient alternative to the more conventional methods of preventing proteolytic degradation. Bacitracin‐linked magnetic affinity adsorbents were employed directly in a fermenter during Bacillus licheniformis cultivation to remove trace amounts of unwanted proteases. The constructed magnetic adsorbents had excellent, highly specific binding characteristics in the fermentation broth (Kd = 1.94 micromolar; Qmax = 222.8 mg/g), which obeyed the Langmuir isotherm and had rapid binding kinetics (equilibrium in <300 s). When applied directly in shake‐flask cultures or in a 1‐L fermenter and then removed by HGMF, the degradation of the model protein bovine serum albumin was stopped. The adsorbents could be recycled and reused during the same fermentation to remove freshly produced proteases, extending the life of the model protein in the fermenter. HGMF may provide an efficient method of stabilizing heterologous proteins produced in cultivation processes.
Comparative pharmacokinetics of prim‐O‐glucosylcimifugin and cimifugin by liquid chromatography–mass spectrometry after oral administration of Radix Saposhnikoviae extract, cimifugin monomer solution and prim‐O‐glucosylcimifugin monomer solution to rats
Authors: Li Yueyue , Zhao Liang , Zhang Hai , Jia Jing , Lv Lei , Zhou Guichen , Chai Yifeng , Zhang Guoqing
Published: January 2012

A sensitive and reliable liquid chromatography–mass spectrometry method has been developed and validated for simultaneous determination of cimifugin and prim‐O‐glucosylcimifugin in rat plasma after oral administration of Radix Saposhnikoviae (RS) extract, prim‐O‐glucosylcimifugin monomer solution and cimifugin monomer solution. Plasma samples were pretreated by protein precipitation with acetonitrile containing the internal standards puerarin and daidzein. LC separation was achieved on a Zorbax SB‐C18 column (150 × 4.6 mm i.d., 5 µm) with 0.1% formic acid in water and methanol by isocratic elution. The detection was carried out in select‐ion‐monitoring mode with a positive electrospray ionization interface. The fully validated method was successfully applied to the pharmacokinetic study of the analytes in rats. A bimodal phenomenon appeared in the concentration–time curve of prim‐O‐glucosylcimifugin and cimifugin after oral administration of RS extract. Prim‐O‐glucosylcimifugin mainly transformed to cimifugin when it was absorbed into blood. Both absorption and elimination of cimifugin after oral administration of RS were longer than after administration of single cimifugin. The pharmacokinetic parameters (AUC0–t, AUC0–∞ and t1/2) of prim‐O‐glucosylcimifugin and cimifugin by giving cimifugin monomer solution, prim‐O‐glucosylcimifugin monomer solution and RS extract had significant differences (P < 0.05). Copyright © 2012 John Wiley & Sons, Ltd.
Simultaneous determination of zolazepam and tiletamine in dog plasma by liquid chromatography coupled to a tandem mass spectrometry
Authors: Noh Kyeumhan , Kim Kil‐Soo , Ahn Byoungki , Archimbault Pillippe , Oh Tae‐Ho , Kang Wonku
Published: January 2012

A mixture of tiletamine, a dissociative anesthetic, and zolazepam, a minor tranquilizer, has been widely used as an anesthetic or an immobilizing agent in a variety of animal species. However, interestingly, their pharmacokinetic behaviors have been published only in polar bears and pigs. In this study, we introduce a sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for determining the two drugs in dog plasma. After simple protein precipitation with acetonitrile including midazolam (internal standard), the analytes were chromatographed on a reversed‐phase column with a mobile phase of 10 mmammonium acetate aqueous solution and acetonitrile (1:4, v/v). The accuracy and precision of the assay were in accordance with FDA regulations for the validation of bioanalytical methods. This method was used to measure the concentrations of zolazepam and tiletamine in plasma after a single intramuscular 10 mg dose of each in beagle dogs. Copyright © 2012 John Wiley & Sons, Ltd.
First isolation of disubstituted cis‐5,6‐dihydro‐1,10‐phenanthrolines. lipase‐mediated resolution of cis‐ and trans‐phenoxy alcohol isomers and assignment of absolute stereochemistry via cd and nmr spectroscopy
Authors: Kohler Lars , Schoffers Elke , Driscoll Erin , Zeller Matthias , Schmiesing Carla
Published: January 2012

5,6‐Dihydro‐1,10‐phenanthrolines can display axial and central chirality. In conjunction with the ligating properties of the diimino moiety, this class of compounds is of great interest to applications in supramolecular chemistry. We report the first preparation of cis‐5,6‐dihydro‐1,10‐phenanthroline derivatives by reacting triphenyl borate with the corresponding epoxide precursor. We found that solvent and temperature choice determined the stereoselectivity of the epoxide opening giving rise to the cis (14:1 dr) or trans (99:1 dr) product. Racemates of each stereoisomeric mixture, cis‐ and trans‐phenoxy alcohol, were separated via highly enantioselective transesterifications with lipase PSCI from Burkholderia cepacia (97% ee, E > 200). Stereochemical assignments were carried out using CD and X‐ray analyses in conjunction with NMR studies of α‐methoxy‐α‐(trifluoromethyl)phenylacetic acid and α‐methoxyphenylacetic acid esters. Chirality, 2012. © 2012 Wiley Periodicals, Inc.
A secured, automated, and dynamic end‐to‐end service level negotiation
Authors: Chalouf M. A. , Krief F.
Published: January 2012

Today, the emerging new services like voice over IP and video on demand require some guarantees in terms of QoS. These services can be accessed using wireless technologies, such as Wi‐Fi or WiMAX (Worldwide Interoperability for Microwave Access). This may make the service delivery vulnerable to security attacks because of the open medium on which wireless technologies are based. Thus, in addition to QoS level, security level must also be guaranteed for the provided services. In this paper, we present the service level negotiation protocol, which ensures a dynamic negotiation of a service level covering both QoS and security. Moreover, the negotiation flow itself could be the target of some malicious attacks. Indeed, these attacks can aim to degrade the service level (QoS and / or security) or to make an entity, which is involved in a negotiation, unavailable, etc. Thus, the objective of this paper is to study the security of the flow corresponding to the negotiation provided by service level negotiation protocol. In fact, the security required by this flow will be provided through the use of three different mechanisms: Web services security, secure sockets layer, and IP security protocol. Because these security mechanisms may have an impact on the negotiation protocol performances, we will also evaluate this impact to adopt the security solution that allows minimizing it. Copyright © 2012 John Wiley & Sons, Ltd.
Combat Experiences, Pre‐Deployment Training, and Outcome of Exposure Therapy for Post‐Traumatic Stress Disorder in Operation Enduring Freedom/Operation Iraqi Freedom Veterans
Authors: Price Matthew , Gros Daniel F. , Strachan Martha , Ruggiero Kenneth J. , Acierno Ron
Published: January 2012

The association between exposure to multiple potentially traumatic events (PTEs) and subsequent increased risk of post‐traumatic stress disorder (PTSD) is well established. However, less is known about the relation between exposure to numerous PTEs, as is typical with military service, and treatment outcome. Furthermore, there has been little research examining military specific protective factors, such as pre‐deployment preparedness, on PTSD treatment response. The current study investigated combat exposure and potential moderators of treatment outcome for exposure therapy in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) veterans with PTSD. One hundred and eleven OEF/OIF veterans diagnosed with PTSD participated in 8 weeks of exposure therapy. Results indicated that increased combat exposure was associated with a reduced rate of change in PTSD symptoms but not depression symptoms. These findings were consistent across two measures of combat exposure. There was preliminary support for the moderating effect of pre‐deployment preparedness on the association between combat exposure and treatment response. Together, these findings suggest that increased combat exposure is associated with poor treatment response in veterans with PTSD; however, this can be reduced by elevated pre‐deployment preparedness. Copyright © 2012 John Wiley & Sons, Ltd.

Key Practitioner Message

Increased combat exposure is associated with poorer treatment response.

Pre‐deployment training is associated with improved treatment response.

PTSD interventions should account for the frequency of combat in military personnel.
Molecular Dynamics Simulations for the Shear Viscosity of the One‐Component Plasma
Authors: Mithen J. P. , Daligault J. , Gregori G.
Published: January 2012

We discuss two methods for determining the shear viscosity of a fluid of particles with Yukawa interaction potential (a one‐component plasma). Both methods are based on computing the equilibrium dynamics using large‐scale molecular dynamics (MD) simulations. Our MD results illustrate that the hydrodynamic method for computing the shear viscosity is feasible and therefore complements the more widely used method based on the Green‐Kubo relation. We expect that in the future our shear viscosity calculations will be used to assist with the interpretation and analysis of x‐ray scattering experiments, which could in principle measure this fundamental dynamical quantity (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strong‐Coupling Theory for a Polarizable Planar Colloid
Authors: Šamaj L. , Trizac E.
Published: January 2012

We propose a strong‐coupling analysis of a polarizable planar interface, in the spirit of a recently introduced Wigner‐Crystal formulation. The system is made up of two moieties: a semi‐infinite medium (z < 0) with permittivity ε ′ while the other half space in z > 0 is occupied by a solution with permittivity ε, and mobile counter‐ions (no added electrolyte). The interface at z = 0 bears a uniform surface charge. The counter‐ion density profile is worked out explicitly for both repulsive and attractive dielectric image cases (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasma Polarization Around Dust Particle in an External Electric Field
Authors: Sukhinin G.I. , Fedoseev A.V. , Khokhlov R.O. , Suslov S.Yu.
Published: January 2012

The effect of plasma polarization around a negatively charged dust particle is investigated with the help of Monte Carlo simulation of ion trajectories in the electric field of the dust particle and an external electric field. The induced dipole moment of such a system was estimated in a wide range of dust particle and plasma parameters. It is shown that the dipole moment is very large, and has a non‐monotonous dependence on the external electric field. For a small external electric field, it weakly depends on the charge of the dust particle. The dipole moment reduces with the decrease of ion mean free path (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of Ionization in the Interaction of Strong Laser Fields with Dense Nanoplasmas
Authors: Hilse P. , Bornath Th. , Moll M. , Schlanges M. , Truong N. X. , Göde S. , Tiggesbäumker J. , Meiwes‐Broer K.‐H.
Published: January 2012

Different experimental methods to maximize the yield of highly charged ions in silver and xenon clusters interacting with intense and ultra‐short optical laser pulses are discussed. Theoretically, the interaction of strong laser fields with clusters is investigated within the nanoplasma model. The time evolution of the laser intensity has been parametrized. The free optimization of the parameters with a genetic algorithm is an effective but expensive tool to control the plasma dynamics. Comparison is given to the parametric control method in which pulse separation and relative intensity ratio of double‐pulses are varied. This method delivers in the case of silver and xenon clusters pulses quite close to the optimal pulse shape (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Short History of Phase Transitions in Ionic Fluids
Authors: Schröer W.
Published: January 2012

The paper reviews the development of theory and experiments concerning the nature of the critical point in ionic fluids. Because of the long‐range nature of the Coulomb interactions the possibility of mean‐field critical behaviour was discussed as a possibility. Although some experiments supported mean‐field criticality, simulations on the model fluid of charged hard spheres and later experiments on ionic solutions have shown that phase transition of ionic systems belong to the Ising universality class like phase transitions in non‐ionic fluids. Experiments concerning the crossover from Ising to mean field‐behaviour are discussed as well as systematic differences between the phase behaviour predicted for the model fluid of charged hard spheres and that observed in ionic solutions (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dysphagia in severe anorexia nervosa: A case report
Authors: Holmes Samantha R.M. , Gudridge Tricia A. , Gaudiani Jennifer L. , Mehler Philip S.
Published: January 2012

Objective:

The purpose of this case report is to increase awareness among clinicians that oropharyngeal dysphagia occurs in patients with severe anorexia nervosa, placing them at risk for aspiration and impeding nutritional rehabilitation.

Method:

We describe a patient with severe anorexia nervosa who manifested symptoms of dysphagia, with resultant aspiration pneumonia, at the time of her admission for medical stabilization.

Results:

The speech pathology team administered dysphagia therapy, using neuromuscular electrical stimulation (NMES) in conjunction with swallowing therapy. Following the course of dysphagia treatment intervention, the patient was able to tolerate an oral diet with improved swallowing function and no ongoing aspiration.

Discussion:

Patients with severe anorexia nervosa should be screened for possible dysphagia. NMES in the treatment of dysphagia in patients with anorexia nervosa may reduce the need for enteral feeds and prolonged hospitalization. © 2012 by Wiley Periodicals, Inc. Int J Eat Disord 2012.
Developmental patterns and family predictors of adolescent weight concerns: A replication and extension
Authors: Lam Chun Bun , McHale Susan M.
Published: January 2012

Objective:

We examined how weight concerns changed across adolescence and whether within‐person changes in parent–adolescent relationships were longitudinally linked to within‐person changes in adolescent weight concerns.

Method:

Participants were mothers, fathers, and the two eldest adolescent siblings from 201 families. Adolescents rated their weight concerns on five occasions across 7 years. Parents rated their acceptance of and conflict with their adolescents, and adolescents rated their depressive symptoms, a year prior to each weight concern measurement.

Results:

Although girls' weight concerns increased from early to late adolescence and then leveled off, boys' weight concerns remained relatively unchanged. Moreover, controlling for adolescents' depressive symptoms, when mothers reported less acceptance of and fathers reported more conflict with their adolescents than usual, adolescents reported more weight concerns than usual in the following year.

Discussion:

Findings highlight the vulnerability of adolescents and the role of both mothers and fathers in the etiology of weight‐related problems. © 2012 by Wiley Periodicals, Inc. Int J Eat Disord 2012.
Graphitic Carbon Nanocapsules: Scaled Preparation, Formation Mechanism, and Use as an Excellent Support for Methanol Electro‐oxidation
Authors: Wang Lei , Tian Chungui , Zhang Hongxing , Fu Honggang
Published: January 2012

Graphitic carbon nanocapsules (GCNs) with high crystallinity and a large specific surface area (SSA) have been prepared in high yield by a solid‐state pyrolysis route using a polyacrylic weak‐base anion‐exchange resin (PAWBA) as the carbon source. A possible mechanism for the formation of the GCNs is proposed based on a series of experiments, including TG, FTIR, Raman, and TEM analyses, as well as on the structure of PAWBA: The catalytic iron particles are surrounded by the active carbon atoms derived from PAWBA during the pyrolytic process, which then escape from thecarbon nanocapsules as the pyrolytic temperature is further increased to finally yield the GCNs. The synthesized GCNs were used as an excellent support of platinumnanoparticles (3–5 nm) for methanol electro‐oxidation. The Pt/GCN electrocatalyst exhibited a higher catalytic activity and better durability towards methanol electro‐oxidation than Pt/C (Vulcan XC‐72R support) and commercial Pt/C(JM) catalysts. The current density of the Pt/GCN catalyst for methanol electro‐oxidation is as high as 275 A/g Pt, whereas for the Pt/C and Pt/C(JM) catalysts the values are only 190 and 184 A/g Pt, respectively.
Polynuclear Copper(I) Complexes with Chelating Bis‐ and Tris‐N‐Heterocyclic Carbene Ligands: Catalytic Activity in Nitrene and Carbene Transfer Reactions
Authors: Tubaro Cristina , Biffis Andrea , Gava Riccardo , Scattolin Elena , Volpe Andrea , Basato Marino , Díaz‐Requejo M. Mar , Perez Pedro J.
Published: January 2012

Di‐ and trinuclear complexes of copper(I) bearing bis‐ or tris‐N‐heterocyclic carbene ligands have been prepared and evaluated as catalysts in nitrene transfer reactions from PhI=NTs to unsaturated and saturated substrates (olefin aziridination and C–H bond amidation) and carbene transfer reactions from diazo compounds to olefins. The complexes exhibited moderate‐to‐high catalytic activity in both processes. The tosylamidation of C–H bonds, previously unreported with a NHC‐containing copper catalyst, was promoted by the dinuclear complexes.
Rab25 increases cellular ATP and glycogen stores protecting cancer cells from bioenergetic stress
Authors: Cheng Kwai Wa , Agarwal Roshan , Mitra Shreya , Lee Ju‐Seog , Carey Mark , Gray Joe W. , Mills Gordon B.
Published: January 2012

Cancer cells are metabolically stressed during tumour progression due to limited tumour vascularity and resultant nutrient, growth factor and oxygen deficiency that can induce cell death and inhibit tumour growth. We demonstrate that Rab25, a small GTPase involved in endosomal recycling, that is genomically amplified in multiple tumour lineages, is a key regulator of cellular bioenergetics and autophagy. RAB25 enhanced survival during nutrient stress by preventing apoptosis and autophagy via binding and activating AKT leading to increased glucose uptake and improved cellular bioenergetics. Unexpectedly, Rab25 induced the accumulation of glycogen in epithelial cancer cells, a process not previously identified. Strikingly, an increase in basal ATP levels combined with AKT‐dependent increases in glucose uptake and glycogen storage allowed maintenance of ATP levels during bioenergetic stress. The clinical relevance of these findings was validated by the ability of a Rab25‐dependent expression profile enriched for bioenergetics targets to identify patients with a poor prognosis. Thus, Rab25 is an unexpected regulator of cellular bioenergetics implicated as a useful biomarker and potential therapeutic target.
How does growth temperature affect cadmium toxicity measured on different life history traits in the soil nematode Caenorhabditis elegans?
Authors: Nørhave Nils J. , Spurgeon David , Svendsen Claus , Cedergreen Nina
Published: January 2012

Environmental factors, in particular temperature, have been shown to affect the toxicity of chemicals. In the present study the authors exposed the nematode Caenorhabditis elegans to five concentrations of Cd (2, 4, 6, 8, and 10 mg Cd/L agar) at four constant temperatures (11, 15, 18, and 21°C) and monitored survival and reproduction on a daily basis. Data were incorporated in a population matrix model to determine the population growth rate (PGR). An additional experiment at 15 and 20°C and 0, 1, 5, and 10 mg Cd/L was performed to include growth measurements in order to relate changes in reproduction to resource allocations between investments in growth and reproduction. The impacts of Cd on PGR increased with increasing temperature, shifting the median effective concentration (EC50) for PGR from 11.6 ± 5.4 and 9.2 ± 1.3 at 11°C and 15°C, to 2.1 ± 0.1 and 1.7 ± 0.4 at 18°C and 21°C. Cadmium and temperature decreased growth rates, but Cd also increased maturation times and decreased final body size. It is hypothesized that Cd toxicity leads to a decrease in nutrient assimilation and that this “chemical anorexia” is more severe at high temperatures, where energy demands for growth and reproduction are the highest. Environ. Toxicol. Chem. 2012;31:787–793. © 2012 SETAC
A moving mesh algorithm for aero‐thermo‐mechanical modelling in turbomachinery
Authors: Amirante D. , Hills N.J. , Barnes C.J.
Published: January 2012

This paper describes the development of a mesh deformation method used for aero‐thermo‐mechanical coupling of turbo‐engine components. The method is based on the nonlinear solution of an elastic medium analogy, solved using finite element discretisation and modified to let the boundary nodes be free to slide over the deflected surfaces. This sliding technique relies on a B‐spline reconstruction of the moving boundary and increases the robustness of the method in situations where the boundary deflection field presents significant gradients or large relative motion between two distinct boundaries. The performance of the method is illustrated with the application to an interstage cavity of a turbine assembly, subjected to the deformations computed by a coupled thermo‐mechanical analysis of the engine component. Copyright © 2011 John Wiley & Sons, Ltd.
Subjective memory complaints in general practice predicts future dementia: a 4‐year follow‐up study
Authors: Waldorff Frans Boch , Siersma Volkert , Vogel Asmus , Waldemar Gunhild
Published: January 2012

Objective

Many older patients in general practice have subjective memory complaints (SMC); however, not all share this information with their general practitioner (GP). The association between SMC and future cognitive decline or dementia is not clear, especially in a general practice population. The aim of this study was to determine the risk for receiving a subsequent hospital‐based dementia diagnosis on the basis of patients' reports of SMC in a primary care setting.

Methods

Prospective cohort survey with 4‐year register‐based follow‐up in general practice. All 17 practices with a total of 24 GPs working in the inner district of Copenhagen municipality, Denmark. A total of 40 865 patients were listed, and 2934 were 65 years or older. Cox proportional hazard models were used to examine the influence of risk factors for hospital‐based dementia diagnosis.

Results

A total of 758 non‐nursing home residents aged 65 years and older consulted their GP in October and November 2002, and, when asked, 177 (24%) reported memory problems, and 50 (6.6%) received a hospital‐based dementia diagnosis within the 4‐years follow‐up. SMC had an adjusted Hazard Ratio (HR) of 2.27 for subsequent dementia diagnosis. Other statistical significant covariates were Mini Mental State Examination < 24 (HR 3.97), age (HR 2.73 for 75–84 years and HR 3.75 for 85+ years) and receiving home care (HR 3.24)

Conclusions

This study indicates that the presence of SMC in an older general practice population is a significant independent predictor for subsequent hospital‐based dementia diagnosis. Thus, the GP could consider inquiring for memory complaints to identify vulnerable older patients. Copyright © 2012 John Wiley & Sons, Ltd.
GABAergic contributions to gating, timing, and phase precession of hippocampal neuronal activity during theta oscillations
Authors: Cutsuridis Vassilis , Hasselmo Michael
Published: January 2012

Successful spatial exploration requires gating, storage, and retrieval of spatial memories in the correct order. The hippocampus is known to play an important role in the temporal organization of spatial information. Temporally ordered spatial memories are encoded and retrieved by the firing rate and phase of hippocampal pyramidal cells and inhibitory interneurons with respect to ongoing network theta oscillations paced by intra‐ and extrahippocampal areas. Much is known about the anatomical, physiological, and molecular characteristics as well as the connectivity and synaptic properties of various cell types in the hippocampal microcircuits, but how these detailed properties of individual neurons give rise to temporal organization of spatial memories remains unclear. We present a model of the hippocampal CA1 microcircuit based on observed biophysical properties of pyramidal cells and six types of inhibitory interneurons: axo‐axonic, basket, bistratistified, neurogliaform, ivy, and oriens lacunosum‐moleculare cells. The model simulates a virtual rat running on a linear track. Excitatory transient inputs come from the entorhinal cortex (EC) and the CA3 Schaffer collaterals and impinge on both the pyramidal cells and inhibitory interneurons, whereas inhibitory inputs from the medial septum impinge only on the inhibitory interneurons. Dopamine operates as a gate‐keeper modulating the spatial memory flow to the PC distal dendrites in a frequency‐dependent manner. A mechanism for spike‐timing‐dependent plasticity in distal and proximal PC dendrites consisting of three calcium detectors, which responds to the instantaneous calcium level and its time course in the dendrite, is used to model the plasticity effects. The model simulates the timing of firing of different hippocampal cell types relative to theta oscillations, and proposes functional roles for the different classes of the hippocampal and septal inhibitory interneurons in the correct ordering of spatial memories as well as in the generation and maintenance of theta phase precession of pyramidal cells (place cells) in CA1. The model leads to a number of experimentally testable predictions that may lead to a better understanding of the biophysical computations in the hippocampus and medial septum. © 2012 Wiley Periodicals, Inc.
Investigation into the daily precipitation variability in the Yangtze River Delta, China
Authors: Sang Yan‐Fang , Wang Zhonggen , Li Zongli , Liu Changming , Liu Xiaojie
Published: January 2012

In this article, by using the daily precipitation data measured at 58 meteorological stations, spatial and temporal variability of daily precipitation including zero rainfall values (called “precipitation”) and without zero rainfall values (called “rain”) and four precipitation extrema (P0, P20, P50, and P100 representing the daily precipitation with the magnitude smaller than 0.1 mm, bigger than 20 mm, 50 mm, and 100 mm per day, respectively) in the Yangtze River Delta (YRD) during 1958–2007 were analyzed, and the effects of urbanization were further investigated. Results indicate that (i) differing from the downward trends in 1958–1985, daily precipitation and rain in 1986–2007 show slowly downward trends in the mid YRD but show upward trends in the northern and southern YRD. (ii) Spatial and temporal variability of the rain is more complex than daily precipitation. Both of them become smaller but show more obvious fluctuations in 1986–2007. (iii) Urbanizations cause not only the urban rainfall island problem but also more obvious fluctuations of rain intensity in the mid YRD, reflecting more uncertainty of daily precipitation variability. (iv) Urbanizations have little effects on the variability of P0 and P100 but cause notable increases of P20 and P50. (v) The spatial variability of daily precipitation and precipitation extrema in 1958–1985 clearly shows a breakpoint at 30°20′N latitude, but the breakpoint disappears afterward because of the effects of urbanization. Copyright © 2012 John Wiley & Sons, Ltd.
Modelling the rainfall–runoff process of the Mara River basin using the Soil and Water Assessment Tool
Authors: Dessu Shimelis Behailu , Melesse Assefa M.
Published: January 2012

The delicate balance between human utilization and sustaining its pristine biodiversity in the Mara River basin (MRB) is being threatened because of the expansion of agriculture, deforestation, human settlement, erosion and sedimentation and extreme flow events. This study assessed the applicability of the Soil and Water Assessment Tool (SWAT) model for long‐term rainfall–runoff simulation in MRB. The possibilities of combining/extending gage rainfall data with satellite rainfall estimates were investigated. Monthly satellite rainfall estimates not only overestimated but also lacked the variability of observed rainfall to substitute gage rainfall in model simulation. Uncertainties related to the quality and availability of input data were addressed. Sensitivity and uncertainty analysis was reported for alternative model components and hydrologic parameters used in SWAT. Mean sensitivity indices of SWAT parameters in MRB varied with and without observed discharge data. The manual assessment of individual parameters indicated heterogeneous response among sub‐basins of MRB. SWAT was calibrated and validated with 10 years of discharge data at Bomet (Nyangores River), Mulot (Amala River) and Mara Mines (Mara River) stations. Model performance varied from satisfactory at Mara Mines to fair at Bomet and weak at Mulot. The (Nash–Sutcliff efficiency, coefficient of determination) results of calibration and validation at Mara Mines were (0.68, 0.69) and (0.43, 0.44), respectively. Two years of moving time window and flow frequency analysis showed that SWAT performance in MRB heavily relied on quality and abundance of discharge data. Given the 5.5% area contribution of Amala sub‐basin as well as uncertainty and scarcity of input data, SWAT has the potential to simulate the rainfall runoff process in the MRB. Copyright © 2012 John Wiley & Sons, Ltd.
“First‐Principles” kinetic monte carlo simulations revisited: CO oxidation over RuO2(110)
Authors: Hess Franziska , Farkas Attila , Seitsonen Ari P. , Over Herbert
Published: January 2012

First principles‐based kinetic Monte Carlo (kMC) simulations are performed for the CO oxidation on RuO2(110) under steady‐state reaction conditions. The simulations include a set of elementary reaction steps with activation energies taken from three different ab initio density functional theory studies. Critical comparison of the simulation results reveals that already small variations in the activation energies lead to distinctly different reaction scenarios on the surface, even to the point where the dominating elementary reaction step is substituted by another one. For a critical assessment of the chosen energy parameters, it is not sufficient to compare kMC simulations only to experimental turnover frequency (TOF) as a function of the reactant feed ratio. More appropriate benchmarks for kMC simulations are the actual distribution of reactants on the catalyst's surface during steady‐state reaction, as determined by in situ infrared spectroscopy and in situ scanning tunneling microscopy, and the temperature dependence of TOF in the from of Arrhenius plots. © 2012 Wiley Periodicals, Inc.
Decrement of cellulose recalcitrance by treatment with ionic liquid (1‐ethyl‐3‐methylimidazolium acetate) as a strategy to enhance enzymatic hydrolysis
Authors: Xiros Charilaos , Vafiadi Christina , Topakas Evangelos , Christakopoulos Paul
Published: January 2012

BACKGROUND: The high crystallinity of cellulose underlies the recalcitrance that this polymer presents in enzymatic degradation. Thus, a pre‐treatment step is applied in most bioconversion processes. Treatments with ionic liquids are considered an emerging pre‐treatment technology, owing to their high efficiency in solvating cellulose, over molecular solvent systems.

RESULTS: Crystalline cellulose with and without ionic liquid (1‐ethyl‐3‐methylimidazolium acetate) treatment, both commercially available, were used as substrates in enzymatic hydrolysis reactions using the earlier evaluated cellulolytic system of Fusarium oxysporum. The in situ removal of the hydrolysate during reactions enhanced the reaction rate as well as the overall glucose production. Ionic liquid treatment significantly decreased cellulose crystallinity and enhanced bioconversion yields and rates. The effects of cellulose structural changes during treatment on hydrolysis rate were investigated and the recalcitrance constants were determined.

CONCLUSION: The study showed that ionic liquid‐treated cellulose became more homogeneous and more easily degradable than the untreated cellulose, a conclusion that was expressed mathematically by the difference in the recalcitrance constants for the two substrates. It was concluded that glucose production from ionic liquid‐treated cellulose could achieve very high conversion yields in consolidated bioprocesses or during simultaneous saccharification and fermentation. Copyright © 2012 Society of Chemical Industry
Kinetic study on biphasic recognition chiral extraction for separation of α‐cyclohexyl‐mandelic acid enantiomers
Authors: Tang Kewen , Li Hongjian , Zhang Panliang
Published: January 2012

BACKGROUND: Chiral solvent extraction is a potentially attractive chiral separation technique. It is essential to know the intrinsic complexation kinetics for selection, design and operation of reactive extraction equipment and for reliable scale‐up. The objective of this research is to study the kinetics of biphasic recognition chiral extraction of α‐cyclohexyl‐mandelic acid (α‐CHMA) enantiomers using a modified Lewis cell.

RESULTS: The experimental results demonstrate that the extraction reaction kinetics is fast, and the reactions are first order with respect to α‐CHMA and second order with respect to D‐IBTA, with forward rate constants of 6.54 × 10−4 mol−2 m6 s−1 for S‐α‐CHMA and 6.84 × 10−4 mol−2 m6 s−1 for R‐α‐CHMA. With increase of HP‐β‐CD concentration in aqueous phase, enantioselectivity increases, while the overall mass transfer coefficients decrease.

CONCLUSIONS: Sufficient enantioselectivity and fast kinetics of extraction can be obtained in the BRCE system at HP‐β‐CD concentration of 0.1 mol L−1 and D‐IBTA concentration of 0.2 mol L−1. These data will be useful in the design of extraction processes. Copyright © 2012 Society of Chemical Industry
Facial vein aneurysm associated with sialadenitis
Authors: Ilica Ahmet Turan , Senturk Senem , Kertmen Mustafa , Bukte Yasar , Bilici Aslan , Atasoy Mehmet Mahir
Published: January 2012

A 20 year‐old man presented with pain and swelling of the left submandibular area. Neck sonography revealed enlargement of the submandibular gland, coarsening of its echotexture with a few calculi and a multiloculated cystic lesion. Doppler sonography revealed venous flow within the cystic lesion and aneurysmal dilatation of the adjacent facial vein. CT angiography confirmed the facial vein aneurysm. We hypothesize that inflammation of the gland had weakened the wall of the adjacent facial vein, causing aneurysmal dilatation. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012