bluuebunny/crossref_metadata_2025 huggingface dataset:
Chiral separation of β‐blockers by MEEKC using neutral microemulsion: Analysis of separation mechanism and further elucidation of resolution equation
Authors: Hu Shao‐Qiang , Lü Wen‐Juan , Ma Yan‐Hua , Hu Qin , Dong Li‐Jun , Chen Xing‐Guo
Published: October 2012

Based on the investigation of the effect of microemulsion charge on the chiral separation, a new chiral separation method with MEEKC employing neutral microemulsion was established. The method used a microemulsion containing 3.0% (w/v) neutral surfactant Tween 20 and 0.8% (w/v, 30 mM) dibutyl l‐tartrate in 40 mM sodium tetraborate buffer to separate the enantiomers of β‐blockers. The effect of major parameters on the chiral separation was investigated. The applied voltage had little effect on the resolution, but the chiral separation could be improved by suppressing the EOF. Nine racemic β‐blockers obtained relatively good enantioseparation after appropriate concentrations of tetradecyl trimethyl ammonium bromide were added into the microemulsion to suppress the EOF. These results were explained based on the analysis of the separation mechanism of the method and deduced separation equations. The resolution equation of the method was further elucidated. It was found that the fourth term in the resolution equation, an additional term compared to the conventional resolution equation for column chromatography, represents the ratio of the relative movement distance between the analyte and microemulsion droplets relative to the effective capillary length. It can be regarded as a correction for the effective capillary length. These findings are significant for the development of the theory of MEEKC and the development of new chiral MEEKC method.
Simultaneous determination of acidic and basic drugs using dual hollow fibre electromembrane extraction combined with CE
Authors: Tabani Hadi , Fakhari Ali Reza , Shahsavani Abolfath
Published: October 2012

The simultaneous extraction of acidic and basic drugs from biological samples is a significant challenge for sample preparation. A novel and efficient method named dual hollow fibre electromembrane extraction combined with CE was applied for the simultaneous extraction and preconcentration of acidic and basic drugs in a single step. Under applied potential of 40 V during the extraction, ibuprofen as an acidic drug and thebaine as a basic drug migrated from a 4 mL aqueous sample solution at neutral pH into 20 μL of each basic (pH 12.5) and acidic (pH 2.0) acceptor phase, respectively; 1‐octanol and 2‐nitrophenyl octyl ether were immobilised in the pores of anodic and cathodic hollow fibres as supported liquid membranes, respectively. A Box–Behnken design and the response surface methodology were used for the optimisation of different parameters on the extraction efficiency. Under the optimised conditions, the enrichment factors were between 150 and 170 and also the LODs ranged from 3 to 7 ng/mL in different samples. The method was reproducible so that intra‐ and inter‐day RSDs% (n = 5) were less than 5.9%. Finally, the method was successfully applied for the simultaneous extraction and determination of acidic and basic drugs from plasma and urine samples.
Application of ionic liquid as additive in determination of three β‐agonists by capillary electrophoresis with amperometric detection
Authors: Li Libo , Du Hongwei , Yu Huan , Xu Lei , You Tianyan
Published: October 2012

CE coupled with amperometric detection method was developed using ionic liquid 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMImBF4) as additive for the simultaneous detection of clenbuterol (CLB), terbutaline (TER), and ractopamine (RAC) in feed. The effects of detection potential, concentration of EMImBF4, pH, and concentration of the running buffer, separation voltage as well as injection time on the separation and detection of these three β‐agonists were investigated in detail. Under the optimum conditions: the detection potential at 1.05 V, 50 mmol/L Tris‐HAc at pH 8.0 with 0.6% (v/v) EMImBF4, electrokinetic injection 6 s at 16 kV and separation voltage at 16 kV, a baseline separation for these three analytes could be achieved within 11 min. Introduction of EMImBF4 into the running buffer resulted in significant improvement in separation selectivity and enhancement in peak currents for those β‐agonists, especially for TER and RAC, which could not be separated in the running buffer without additive. The method exhibited wide linear range with LOD (S/N = 3) of 2, 1, and 2 nmol/L for CLB, TER, and RAC, respectively. The precision was determined in both intraday (n = 5) and interday (n = 3) assays, and the RSDs for both migration time and peak current were less than 6%. The proposed method was also applied to analyze β‐agonists in feed sample.
Implications of global climate change for natural resource damage assessment, restoration, and rehabilitation
Authors: Rohr Jason R. , Johnson Philip , Hickey Christopher W. , Helm Roger C. , Fritz Alyce , Brasfield Sandra
Published: October 2012

Various international and national regulations hold polluters liable for the cleanup of released hazardous substances and the restoration/rehabilitation of natural resources to preincident baseline conditions, a process often referred to as natural resource damage assessment and restoration (NRDAR). Here, we, the authors, describe how global climate change (GCC) will challenge each of the steps of NRDAR processes and offer eight recommendations to improve these processes in light of GCC. First, we call for a better understanding of the net effects of GCC and contaminants on natural resources. Second, we urge facilities and environmental managers to plan for GCC-related factors that are expected to increase the probability of contaminant releases. Third, we suggest re-evaluating definitions of baseline and reference conditions given that GCC will alter both their trajectories and variability. Fourth, we encourage long-term monitoring to improve the quantification of baseline conditions that will change as climate changes. This will enhance the accuracy of injury assessments, the effectiveness of restoration, and the detection of early warning signs that ecosystems are approaching tipping points. Fifth, in response to or anticipation of GCC, restoration projects may need to be conducted in areas distant from the site of injury or focused on functionally equivalent natural resources; thus, community involvement in NRDAR processes will be increasingly important. Sixth, we promote using NRDAR restoration projects as opportunities to mitigate GCC-related impacts. Seventh, we recommend adaptive management approaches to NRDAR processes and communication of successes and failures widely. Finally, we recommend focusing on managing the stressors that might be exacerbated by GCC, such as pollution and habitat loss, because there is a long history of successfully mitigating these stressors, which can be more easily managed on local scales than climate change. We believe that adoption of these recommendations will lead to a more efficacious NRDAR process, despite the challenges posed by climate change. Environ. Toxicol. Chem. 2013;32:93–101. © 2012 SETAC
Attention modulates the dorsal striatum response to love stimuli
Authors: Langeslag Sandra J. E. , van der Veen Frederik M. , Röder Christian H.
Published: October 2012

In previous functional magnetic resonance imaging (fMRI) studies concerning romantic love, several brain regions including the caudate and putamen have consistently been found to be more responsive to beloved‐related than control stimuli. In those studies, infatuated individuals were typically instructed to passively view the stimuli or to think of the viewed person. In the current study, we examined how the instruction to attend to, or ignore the beloved modulates the response of these brain areas. Infatuated individuals performed an oddball task in which pictures of their beloved and friend served as targets and distractors. The dorsal striatum showed greater activation for the beloved than friend, but only when they were targets. The dorsal striatum actually tended to show less activation for the beloved than the friend when they were distractors. The longer the love and relationship duration, the smaller the response of the dorsal striatum to beloved‐distractor stimuli was. We interpret our findings in terms of reinforcement learning. By virtue of using a cognitive task with a full factorial design, we show that the dorsal striatum is not activated by beloved‐related information per se, but only by beloved‐related information that is attended. Hum Brain Mapp 35:503–512, 2014. © 2012 Wiley Periodicals, Inc.
Synthesis of 15‐, 16‐, and 17‐Membered Bis‐C‐Pivot Macrocycles Consisting of N2O2 Donor‐Type Crown Ethers and Dialkyl Phosphonates
Authors: Koçak Selen Bilge , Üçkardeş Hale
Published: October 2012

Bis‐C‐pivot macrocycles containing aminophosphonate functions (5–10) have been synthesized and characterized by elemental analysis, FTIR, MS, 1D 1H, 13C and 31P NMR, and 2D HETCOR techniques. The phosphorylation reaction of dibenzo‐bis‐imino crown ethers (1–4) with dimethyl and diethyl phosphite used here has the potential to provide bis‐C‐pivot macrocycles (5–10), which possess two stereogenic C‐centers giving rise to diastereoisomers (meso and racemic). Detailed spectral assignments for the meso and racemic forms of the compounds are reported on the basis of chemical shifts, signal intensities, spin–spin coupling constants, and splitting patterns. The bis‐C‐pivot macrocycles (5–10) may serve as a potential new class of supramolecular host molecules.
Monetary crisis: A 2012 update
Authors: Wolf Fran , Tackett James A.
Published: October 2012

The authors of this article, both professors of finance, have taken a new look at the ongoing monetary crisis. The trends they see are very sobering. They predict that 2012 will be viewed as a pivotal point in history—when rational business planning, based on macroeconomic trends and data, became nearly impossible. The normal business cycle has been replaced by a sustained pattern of high unemployment and abnormally slow growth—combined with a lurking threat of either a full‐blown depression or hyperinflation. And political gridlock in Washington and Europe means governments cannot develop a long‐term solution. To help companies safely navigate these choppy seas, the authors carefully evaluate what is knowable, what businesses should expect, and what should be done. © 2012 Wiley Periodicals, Inc.
Treasurers under investigation
Authors: Shapiro David
Published: October 2012

Questionable actions by treasurers lie at the heart of many financial scandals and investigations. Cash and liquid assets—a primary concern of treasurers—have inherently high risk. So it is not surprising that the risks of treasury fraud and mismanagement require special design, monitoring, and auditing—all with continuous diligence. The author takes a look at some recent cases where treasurers have been under investigation, and reveals insights about how to prevent such disasters. © 2012 Wiley Periodicals, Inc.
Excess corporate cash: Follow the money
Authors: Le Guyader Louis P.
Published: October 2012

American corporations reportedly hold in excess of $1.7 trillion in cash as of July 2012. Can the broader concept of liquidity help us understand the current situation better? Since no benchmarks exist to de‐termine excess liquidity on a corporate balance sheet, why do balance sheets still make most investors and analysts believe that corporations are holding too much cash? And the author makes a surprising revelation: Much of the cash buildup is concentrated in only 10 companies. © 2012 Wiley Periodicals, Inc.
Cash and fraud: A destructive alliance revisited
Authors: Burnett Royce D. , Margolis Donna M. , Elder Jennifer H.
Published: October 2012

By all accounts, today's business environment is a “perfect storm” for fraud. Today's economic climate places more emphasis on success—no matter how it is achieved. Many business leaders and managers begin to rationalize away any wrongdoings as completely appropriate. And computer technology has often made fraud easier. As a result of all this, self‐serving and inappropriate decisions may now routinely be made without any without fear of scrutiny. In layman's terms, this is a workable definition of fraud. The authors of this article take a close look at this troubling situation and discuss what to do about it. © 2012 Wiley Periodicals, Inc.
Executive briefing: Effective asset management
Authors: Edwards James B.
Published: October 2012

This briefing discusses the fundamental principles of effective asset management. The author provides a strategic framework that companies can use to better manage their assets. © 2012 Wiley Periodicals, Inc.
Kinetic study of in situ normal and AGET atom transfer radical copolymerization of n–butyl acrylate and styrene: Effect of nanoclay loading and catalyst concentration
Authors: Ahmadian‐Alam Leila , Haddadi‐Asl Vahid , Hatami Leila , Roghani‐Mamaqani Hossein , Salami‐Kalajahi Mehdi
Published: October 2012

The effect of clay nanolayers and catalyst concentration on the kinetics of atom transfer radical copolymerization of styrene and butyl acrylate initiated by activators generated by electron transfer (AGET initiation system) or an alkyl halide (normal initiation system) was studied. Monomer conversion was studied by attenuated total reflection–Fourier transform infrared spectroscopy, and also proton nuclear magnetic resonance (1H NMR) spectroscopy was utilized to evaluate the heterogeneity in the composition of poly(styrene‐co‐butyl acrylate) chains. A decrease in the copolymerization rate of styrene and butyl acrylate in the presence of clay platelets was observed since clay layers confine the accessibility of monomer and growing radical chains. Considering the linear first‐order kinetics of the polymerization, successful AGET and normal atom transfer radical polymerization (ATRP) in the presence of clay nanolayers were carried out. Consequently, poly(styrene‐co‐butyl acrylate) chains with narrow molecular weight distribution and low polydispersity indices (1.13–1.15) were obtained. The linearity of ln([M]0/[M]) versus time and molecular weight distribution against conversion plots indicates that the proportion of propagating radicals is almost constant during the polymerization, which is the result of insignificant contribution of termination and transfer reactions. Controlled synthesis of poly(styrene‐co‐butyl acrylate)/clay is implemented with the diminishing catalyst concentration of copper(I) bromide/N,N,N′,N′′,N′′‐pentamethyl diethylene triamine without affecting the copolymerization rate of normal ATRP. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 789–799, 2012
Tailored Optical Microsystems for Photonic Applications
Authors: Forrer Martin , Gisler Thomas
Published: October 2012

Innovation in applications such as white‐light illumination, fluorescence excitation and industrial metrology strongly relies on the availability of compact optical microsystems with application‐driven and integrated photonic functions of the diode laser. In these optical microsystems multiple lasers and photonic functions are used to obtain the desired results by the combination of specific advantages of diode lasers. Optical microsystem technology allows to target specific applications by joining various optical functions of diode lasers, such as combining multiple wavelengths into free‐space or fiber‐coupled outputs or driving by analog or digital electronic signals from external sources.
The use of DDAVP in children with bleeding disorders
Authors: Ben‐Ami Tal , Revel‐Vilk Shoshana
Published: October 2012

Desmopressin (1‐deamino‐8‐D‐arginine vasopressin, DDAVP) has been used in children with von Willebrand disease (VWD) and Hemophilia A for almost 35 years. This treatment has substantially lowered the number of children exposed to human plasma derived products, with a good safety profile, and at very low cost. The response to DDAVP has been shown to be associated with age, baseline factor level, and genetic mutations. A DDAVP challenge test is recommended. DDAVP has also been used to prevent and treat bleeding episodes in children with platelet function defects and other disorders associated with bleeding tendency. Pediatr Blood Cancer 2012; 60: S41–S43. © 2012 Wiley Periodicals, Inc.
What we have learned from inherited platelet disorders
Authors: Israels Sara J. , Rand Margaret L.
Published: October 2012

Identifying the molecular basis of inherited platelet disorders has contributed to our understanding of normal platelet physiology. Many of these conditions are rare, but close observation of clinical and laboratory phenotype, and subsequent identification of the abnormal protein and mutated gene, have provided us with unique opportunities to examine specific aspects of platelet biogenesis and function. Phenotype–genotype association studies are providing a detailed understanding of the structure and function of platelet membrane receptors, the biogenesis and release of platelet granules, and the assembly of the cytoskeleton. Genetic polymorphisms contributing to decreased or increased platelet adhesion and activation may translate into increased clinical risks for bleeding or thrombosis. More recently, genome wide association studies have identified new genes contributing to the variation in normal platelet function. Pediatr Blood Cancer 2012; 60: S2–S7. © 2012 Wiley Periodicals, Inc.
Ultrasonic Nebulisation Extraction: Extraction Column Coupled with Liquid Phase Microextraction for Analysis of the Volatile Organic Compounds in Foeniculum vulgare Mill. as a Model
Authors: Yu Cui , Yang Jinjuan , Wang Yeqiang , Wei Hongmin , Zhang Hanqi , Shi Yuhua
Published: October 2012

Introduction

As the concentrations of the volatile organic compounds are always low and their matrix is complex, it is necessary to pre‐concentrate the volatile organic compounds before analysis. Ultrasonic nebulisation extraction with a self‐made extraction column coupled with liquid phase microextraction is developed for the extraction of active constituents from spices.

Objective

To develop an environmentally compatible extraction technique for the preparation and analysis of the volatile organic compounds from spices.

Method

The sample is placed into the nebulisation vessel of a nebulisation humidifier and a purging gas is blown through the vessel continuously. When the nebuliser is switched on, a ultrasonic fountain is formed by ultrasonic vibration and the target analytes are transferred from the sample solution to the vapour phase and then concentrated on the extraction solvent in the extraction column. After extraction for 3 min and allowed to stand upright for 5 min, the extract is analysed by GC and GC–MS. Different methods of comparison can then be carried out.

Results

Optimum conditions were found to be: 30 μL of n‐tetradecane as the extraction solvent, a flow rate for the purging gas of 40 mL/min, a purging time of 3 min and a standing time was 5 min. The contents of constituents in the extract obtained by the proposed method were close to those obtained by hydrodistillation (HD). Moreover, the proposed method achieves higher enrichment efficiency.

Conclusion

A method was developed for the extraction of volatile organic compounds from spices. The study has shown that it is a fast and environmentally sustainable technique. Copyright © 2012 John Wiley & Sons, Ltd.
A flexible docking approach for prediction of T cell receptor–peptide–MHC complexes
Authors: Pierce Brian G. , Weng Zhiping
Published: October 2012

T cell receptors (TCRs) are immune proteins that specifically bind to antigenic molecules, which are often foreign peptides presented by major histocompatibility complex proteins (pMHCs), playing a key role in the cellular immune response. To advance our understanding and modeling of this dynamic immunological event, we assembled a protein–protein docking benchmark consisting of 20 structures of crystallized TCR/pMHC complexes for which unbound structures exist for both TCR and pMHC. We used our benchmark to compare predictive performance using several flexible and rigid backbone TCR/pMHC docking protocols. Our flexible TCR docking algorithm, TCRFlexDock, improved predictive success over the fixed backbone protocol, leading to near‐native predictions for 80% of the TCR/pMHC cases among the top 10 models, and 100% of the cases in the top 30 models. We then applied TCRFlexDock to predict the two distinct docking modes recently described for a single TCR bound to two different antigens, and tested several protein modeling scoring functions for prediction of TCR/pMHC binding affinities. This algorithm and benchmark should enable future efforts to predict, and design of uncharacterized TCR/pMHC complexes.
Structural stratification of Sr1 − xCaxRuO3 thin films: Influence of aging process
Authors: Młynarczyk Marcin , Szot Krzysztof , Poppe Ulrich , Breuer Uwe , Mi Shaobo , Psiuk Bronisław , Görlich Edward A. , Tomala Krzysztof , Waser Rainer
Published: October 2012

Epitaxial Sr1 − xCaxRuO3 thin films were grown on SrTiO3 and LaAlO3 substrates with use of high pressure dc‐sputtering. A number of complementary methods: X‐ray diffraction (XRD), Rutherford backscattering (RBS), high resolution transmission electron microscopy (HRTEM), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), atomic force microscopy (AFM), and X‐ray photoemission spectroscopy (XPS) was used to characterize both in‐depth and lateral structure features.

Fully strained thin films were obtained with a tetragonal lattice cell pronouncedly elongated in an out‐of‐plane direction, independent on details of deposition conditions. Growth types varied from a single layer‐by‐layer two‐dimensional (2D) mode to three‐dimensional (3D) spiral precipitations of different size. Interface layer between the substrate and the thin film as well as its surface suffer from considerable deviations from nominal stoichiometry, basically resulting from Ru deficiency. Samples stored under normal conditions undergo further compositional change of the surface region. The process of aging, extended over several days, involves incorporation of water and carbon dioxide present in an ambient atmosphere and a subsequent surface reconstruction. For samples deposited on SrTiO3 the valence band is indicative of a metallic character of the sample interior regardless of Ca content. The heterogeneous in‐depth profile of the thin films is extremely important in fabrication of nanodevices, especially those based on ultrathin layers.

magnified image

Examination summary of Sr0.8Ca0.2RuO3 thin films, deposited on SrTiO3, methods used and essential conclusions.
Recent progress in the understanding of exciton dynamics within phosphorescent OLEDs
Authors: Reineke Sebastian , Baldo Marc A.
Published: October 2012

Excited states of organic molecules (excitons) are the heart of any organic electroluminescent device. They mediate the conversion of injected charges – electrons and holes – into photons. Phosphorescent emission originating from triplet excitons is especially important, as it is to date the only general route to enable unity charge‐to‐photon conversion efficiencies. In this paper, we discuss the key aspects of excitons, following the excited state lifecycle. First, we review fundamentals of singlet and triplet exciton formation in organic semiconductors, followed by a discussion of concepts that aim to alter the singlet‐to‐triplet formation rates to enable higher electroluminescence yields in the fluorescence manifold. Subsequently, we focus on the exciton distribution within the organic semiconductor material during its lifetime. The processes involved ultimately determine organic light‐emitting diode (OLED) performance and are especially key in the development of concepts for white emission, where precise balance of the exciton between different emitter species control the emitted color. We close this paper with discussion of non‐linear effects at high excitation levels that, to date, limit the high brightness efficiency of phosphorescent OLEDs.
Optical study of defects in nano‐diamond films grown in linear antenna microwave plasma CVD from H2/CH4/CO2 gas mixture
Authors: Varga M. , Remes Z. , Babchenko O. , Kromka A.
Published: October 2012

We present the study on optical quality of nanocrystalline diamond (NCD) films with submicron grain size grown from H2/CH4/CO2 gas mixture on alkali‐free borosilicate glass substrates using the commercially available large area linear antenna pulsed microwave plasma chemical vapor deposition (CVD) system. The NCD films were characterized by Raman spectroscopy, atomic force microscopy, and scanning electron microscopy. The NCD layers are optically transparent and show low optical scattering. The defect states measured by photo‐thermal deflection spectroscopy (PDS) and dual beam photocurrent spectroscopy (DBPS) are dominated by the non‐diamond carbon phases localized at grain boundaries with the characteristic shape of the optical absorption spectrum and the photo‐ionization threshold in a near infrared region. The sp2‐related defect density increases for samples grown at higher pressure. From DBPS we estimate the concentration of substitutional nitrogen to be below 10 ppm. The optimized NCD layers show the photoionization threshold in UV region above 5 eV and a broad exponential tail below 5 eV.
Extending the Shelf Life of Victoria Table Grapes by High Permeability and Fungicide Packaging at Room Temperature
Authors: Xu Wencai , Li Dongli , Fu Yabo , Liu Zunzhong , Wang Yajun , Yu Xuemei , Shang Wei
Published: October 2012

Grapes are one of the most delicious fruits in the world, but normally, they only have a short shelf life at room temperature, a result of their susceptibility to body water loss and grey mould infection. In this study, we developed an active packaging film (APF), which has a sandwich structure with outer and inner layers made of zeolite‐modified low‐density polyethylene (LDPE) with fungicide additives between the two layers. The APF has high permeability for oxygen and is capable of continuously releasing low‐concentration sulfur dioxide over 48 days. The grape storage experiments showed that the shelf life of Victoria table grapes packaged in these APF‐made bags at room temperature was extended to 18 days, compared with 14 days for conventional LDPE packaging and 10 days for unpackaged grapes. At 18 days' storage in APF packaging bags, water loss, berry shatter and berry decay were less than 0.5%, 3% and 5%, respectively, whereas the total soluble solid content and firmness changed only slightly. Copyright © 2012 John Wiley & Sons, Ltd.
Theoretical investigation of gas phase ethanol–(water)n(n= 1–5) clusters and comparison with gas phase pure water clusters (water)n(n= 2–6)
Authors: Han Guangzhan , Ding Yanli , Qian Ping , Zhang Chao , Song Wei
Published: October 2012

Various properties (such as optimal structures, structural parameters, hydrogen bonds, natural bond orbital charge distributions, binding energies, electron densities at hydrogen bond critical points, cooperative effects, and so on) of gas phase ethanol–(water)n(n= 1–5) clusters with the change in the number of water molecules have been systematically explored at the MP2/aug‐cc‐pVTZ//MP2/6‐311++G(d,p) computational level. The study of optimal structures shows that the most stable ethanol‐water heterodimer is the one where exists one primary hydrogen bond (OH…O) and one secondary hydrogen bond (CH …O) simultaneously. The cyclic geometric pattern formed by the primary hydrogen bonds, where all the molecules are proton acceptor and proton donor simultaneously, is the most stable configuration for ethanol–(water)n(n= 2–4) clusters, and a transition from two‐dimensional cyclic to three‐dimensional structures occurs atn= 5. At the same time, the cluster stability seems to correlate with the number of primary hydrogen bonds, because the secondary hydrogen bond was extremely weaker than the primary hydrogen bond. Furthermore, the comparison of cooperative effects between ethanol–water clusters and gas phase pure water clusters has been analyzed from two aspects. First of all, for the cyclic structure, the cooperative effect in the former is slightly stronger than that of the latter with the increasing of water molecules. Second, for the ethanol–(water)5and (water)6structure, the cooperative effect in the former is also correspondingly stronger than that of the latter except for the ethanol–(water)5book structure. © 2012 Wiley Periodicals, Inc.
Epigenetic change detection and pattern recognition via Bayesian hierarchical hidden Markov models
Authors: Wang Xinlei , Zang Miao , Xiao Guanghua
Published: October 2012

Epigenetics is the study of changes to the genome that can switch genes on or off and determine which proteins are transcribed without altering the DNA sequence. Recently, epigenetic changes have been linked to the development and progression of disease such as psychiatric disorders. High‐throughput epigenetic experiments have enabled researchers to measure genome‐wide epigenetic profiles and yield data consisting of intensity ratios of immunoprecipitation versus reference samples. The intensity ratios can provide a view of genomic regions where protein binding occur under one experimental condition and further allow us to detect epigenetic alterations through comparison between two different conditions. However, such experiments can be expensive, with only a few replicates available. Moreover, epigenetic data are often spatially correlated with high noise levels. In this paper, we develop a Bayesian hierarchical model, combined with hidden Markov processes with four states for modeling spatial dependence, to detect genomic sites with epigenetic changes from two‐sample experiments with paired internal control. One attractive feature of the proposed method is that the four states of the hidden Markov process have well‐defined biological meanings and allow us to directly call the change patterns based on the corresponding posterior probabilities. In contrast, none of existing methods can offer this advantage. In addition, the proposed method offers great power in statistical inference by spatial smoothing (via hidden Markov modeling) and information pooling (via hierarchical modeling). Both simulation studies and real data analysis in a cocaine addiction study illustrate the reliability and success of this method. Copyright © 2012 John Wiley & Sons, Ltd.
Separation Membranes Constructed from Inorganic Nanofibers by Filtration Technique
Authors: Yu Qing , Mao Yiyin , Peng Xinsheng
Published: October 2012

Nanofibrous materials have been extensively investigated and used as building blocks for various nanodevices, due to their unique one‐dimensional structures. Recently, novel membranes constructed by using nanofibers have been reported by various techniques. Here, we will give a critical review of our recent research on the general solution processed unique sub‐3 nm thin metal hydroxide nanofibers and their application for constructing ultrathin separation membranes via filtration technique. The superior separation performances of these membranes hold the promising future for pressure‐driven membrane separation processes.
Fetal fraction in maternal plasma cell‐free DNA at 11–13 weeks' gestation: relation to maternal and fetal characteristics
Authors: Ashoor G. , Syngelaki A. , Poon L. C. Y. , Rezende J. C. , Nicolaides K. H.
Published: October 2012

Objective

To examine the possible effects of maternal and fetal characteristics on the fetal fraction in maternal plasma cell‐free (cf) DNA at 11–13 weeks' gestation and estimate the proportion of pregnancies at high risk of non‐invasive prenatal testing (NIPT) failure because the fetal fraction is less than 4%.

Methods

In 1949 singleton pregnancies at 11–13 weeks' gestation cf‐DNA was extracted from maternal plasma. Chromosome‐selective sequencing of non‐polymorphic and polymorphic loci, where fetal alleles differ from maternal alleles, was used to determine the proportion of cf‐DNA that was of fetal origin. Multivariable regression analysis was used to determine significant predictors of the fetal fraction among maternal and fetal characteristics.

Results

The fetal fraction decreased with increased maternal weight, it was lower in women of Afro‐Caribbean origin than in Caucasians and increased with fetal crown–rump length, serum pregnancy‐associated plasma protein‐A, serum free β‐human chorionic gonadotropin, smoking and trisomy 21 karyotype. The median fetal fraction was 10.0% (interquartile range, 7.8–13.0%) and this decreased with maternal weight from 11.7% at 60 kg to 3.9% at 160 kg. The estimated proportion with fetal fraction below 4% increased with maternal weight from 0.7% at 60 kg to 7.1% at 100 kg and 51.1% at 160 kg.

Conclusions

Fetal fraction in maternal plasma cf‐DNA is affected by maternal and fetal characteristics.Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Plastie pénoscrotale pour volumineux éléphantiasis des organes génitaux externes : à propos d’un cas à la clinique universitaire d’urologie-andrologie de Cotonou
Authors: Gandaho I. , Avakoudjo J. , Hounnasso P. -P. , Hodonou F. , Akpo C.
Published: October 2012

Bien qu’ayant été par le passé une zone d’endémie filarienne, les séquelles de la filariose lymphatique deviennent de plus en plus rares au Bénin. Nous rapportons un cas de volumineux éléphantiasis pénoscrotal pris en charge à la clinique universitaire d’urologie-andrologie de Cotonou. Il a été réalisé une plastie pénoscrotale par réduction volumétrique et reconstitution scrotale par deux lambeaux latéraux. Les résultats après un recul de six mois sont satisfaisants.
A Walk in Customers’ Shoes: How Attentional Bias Modification Affects Ownership of Integrity-violating Social Media Posts
Authors: van Laer Tom , de Ruyter Ko , Cox David
Published: October 2012

The number of social media posts that expose company integrity violations has increased dramatically. In response, some companies empower employees to respond to customer blogs, which requires employees to recognize the customer's perspective. We show that attentional bias modification can be used to prime employees of two global Fortune 100 companies with a self-sufficiency or empathy bias. The results indicate that narrative transportation, or the extent to which employees mentally enter the world evoked by a customer's story, mediates the effect of attentional bias on two relevant psychological ownership dimensions: acknowledgment of responsibility and willingness to respond. Participants with a self-sufficiency bias neither acknowledge responsibility nor want to respond. However, participants primed with an empathy bias take responsibility for the customer's case and respond to the integrity violation. We find evidence for two boundary conditions of this effect: (1) it strengthens when the employee perceives the customer's financial vulnerability as high and (2) it weakens when the customer is impolite in the blog post.
Metabolomics approach for predicting response to neoadjuvant chemotherapy for breast cancer
Authors: Wei Siwei , Liu Lingyan , Zhang Jian , Bowers Jeremiah , Gowda G.A. Nagana , Seeger Harald , Fehm Tanja , Neubauer Hans J. , Vogel Ulrich , Clare Susan E. , Raftery Daniel
Published: October 2012

Breast cancer is a clinically heterogeneous disease, which necessitates a variety of treatments and leads to different outcomes. As an example, only some women will benefit from chemotherapy. Identifying patients who will respond to chemotherapy and thereby improve their long‐term survival has important implications to treatment protocols and outcomes, while identifying non responders may enable these patients to avail themselves of other investigational approaches or other potentially effective treatments. In this study, serum metabolite profiling was performed to identify potential biomarker candidates that can predict response to neoadjuvant chemotherapy for breast cancer. Metabolic profiles of serum from patients with complete (n = 8), partial (n = 14) and no response (n = 6) to chemotherapy were studied using a combination of nuclear magnetic resonance (NMR) spectroscopy, liquid chromatography–mass spectrometry (LC–MS) and statistical analysis methods. The concentrations of four metabolites, three (threonine, isoleucine, glutamine) from NMR and one (linolenic acid) from LC–MS were significantly different when comparing response to chemotherapy. A prediction model developed by combining NMR and MS derived metabolites correctly identified 80% of the patients whose tumors did not show complete response to chemotherapy. These results show promise for larger studies that could result in more personalized treatment protocols for breast cancer patients.
TYPES OF MARRIAGES, POPULATION STRUCTURE AND GENETIC DISEASE
Authors: MACHADO T. M. B. , BOMFIM T. F. , SOUZA L. V. , SOARES N. , SANTOS F. L. , ACOSTA A. X. , ABE-SANDES K.
Published: October 2012

A high occurrence rate of consanguineous marriages may favour the onset and increased frequency of autosomal recessive diseases in a population. The population of Monte Santo, Bahia, Brazil, has a high frequency of rare genetic diseases such as mucopolysaccharidosis type VI, whose observed frequency in this population is 1:5000, while the incidence of this disease recorded in other regions of the world varies from 1:43,261 in Turkey to 1:1,505,160 in Switzerland. To verify the influence of consanguineous marriage on the increased frequency of observed genetic diseases in this population, the population structure and frequency of different types of marriage during different time periods were evaluated. A total of 9765 marriages were found in an analysis of parish marriage records from the city. Over three periods, 1860–1895, 1950–1961 and 1975–2010, the inbreeding rates were 37.1%, 13.2% and 4.2% respectively. Although there was a high rate of inbreeding, endogamic marriages were the dominant marriage type in all three periods. In the most recent period, there was an increase in the number of exogamous marriages and those among immigrants, but most of these occurred among individuals from cities that neighbour Monte Santo. The low rate of migration and high frequency of endogamic and consanguineous marriages show that growth of this population is predominantly internal and could explain the occurrence, and increase in frequency, of recessive genetic diseases in the city.
Impact of genetic risk assessment on nutrition-related lifestyle behaviours
Authors: Vernarelli Jacqueline A.
Published: October 2012

Genetic susceptibility testing for common complex disease is a practice that is currently in clinical use. There are two types of gene mutations, and therefore, two varieties of genotype testing: deterministic and susceptibility. As the term suggests, deterministic genes determine whether or not a person will develop a given trait in Mendelian fashion, such as Huntington's disease. Genotype screening for such deterministic mutations has existed for decades, and is commonly used in routine medical practice. In recent years, the sequencing of the human genome has identified several ‘susceptibility genes’ or genes with incomplete penetrance. Mutations in these genes may increase disease susceptibility, but are not causative for disease. Genetic susceptibility testing allows unaffected individuals to obtain risk information for a variety of common complex diseases and health conditions including Alzheimer's disease (AD), CVD, cancer and diabetes. The availability of genetic susceptibility testing has increased over the past decade, and several studies are now focusing on the impact that genetic testing has on health and other lifestyle behaviours related to nutrition. The aim of this paper is to review the literature and evaluate what, if any, impact genetic risk assessment has on behaviours related to nutrition and physical activity. This paper summarises seven clinical studies that evaluated the impact of disclosing genetic risk information for disease on nutrition-related health behaviour changes. Of these seven studies, only three studies reported that health behaviour change was influenced by genotype disclosure.
Neurocognitive Late Effects of Pediatric Brain Tumors of the Posterior Fossa: A Quantitative Review
Authors: Robinson Kristen E. , Fraley Claire E. , Pearson Matthew M. , Kuttesch John F. , Compas Bruce E.
Published: October 2012

Deficits in neurocognitive functioning are an important area of late effects in survivors of pediatric brain tumors; however, a quantitative analysis of the magnitude of these deficits in survivors of brain tumors of the posterior fossa has not been conducted. Despite tumor locations in the posterior regions of the brain, individual studies have documented deficits in a variety of domains, reflective of impairment in other brain regions. The current study provides a comprehensive meta-analysis of literature on neurocognitive late effects found in survivors of posterior fossa tumors. Results indicated significant deficits in both specific and broad indices of neurocognitive functioning, and the overall magnitude of effects across domains ranged from medium to large (g= −0.62 to −1.69) with a large mean overall effect size (g= −1.03). Moderator analyses indicated significantly greater effects for survivors diagnosed at a younger age and those who received radiation therapy. These findings underscore the importance of monitoring neurocognitive late effects in survivors of pediatric brain tumors of the posterior fossa, as well as the need for more consistent consideration of demographic, diagnostic, and treatment-related variables to allow for examination of factors that moderate these deficits. (JINS, 2012,19, 1–10)
Prospective Memory and Antiretroviral Medication Non-Adherence in HIV: An Analysis of Ongoing Task Delay Length Using the Memory for Intentions Screening Test
Authors: Poquette Amelia J. , Moore David J. , Gouaux Ben , Morgan Erin E. , Grant Igor , Woods Steven Paul ,   The HNRP Group
Published: October 2012

Using multi-process framework by McDaniel and Einstein (2000), the current study examined whether the length of prospective memory (PM) delay intervals as measured by the 2- and 15-min subscales of the Memory for Intentions Screening Test (MIST) have differential predictive value for antiretroviral (ARV) adherence. Participants included 74 HIV-infected individuals whose ARV adherence was tracked with an electronic monitoring system. Participants were classified as “adherent” (n = 49) or “non-adherent” (n = 25) based on recorded pill bottle openings of ≥90% of prescribed doses over 30 days. An adherence group by MIST delay interval interaction was observed, such that non-adherent participants had worse performance on the 15-min, but not 2-min delay PM MIST subscales. The observed MIST 15-min delay effects were significantly more pronounced on time- versus event-cued PM trials. Long-delay time-based PM was predictive of non-adherence independent of demographics, mood state, self-reported adherence, and general cognitive functioning. Findings from this clinical study indicate that ARV non-adherence may be particularly associated with deficits in strategic cue monitoring over longer PM delays, which may inform interventions to improve adherence among persons living with HIV infection. (JINS, 2012, 18, 1–7)
Microscopy and Microanalysis of Hematological Parameters in Common Carp, Cyprinus carpio, Inhabiting a Polluted Lake in North East India
Authors: Massar Bashida , Dey Sudip , Barua R. , Dutta K.
Published: October 2012

Optical and scanning electron microscopy (SEM) of red blood cells (RBCs) of common carp, Cyprinus carpio, inhabiting a polluted lake in Northeast India revealed a number of abnormalities. About 7% of the RBC showed the presence of a micronucleus, besides the presence of some bi-nucleated and abnormally shaped nuclei. RBCs, white blood cells, and hemoglobin content were found to be reduced significantly as compared to the control. SEM showed the presence of spherocytes, early stages of echinocytes, cytoplasmic blebbing, erythrocytes with contraction from one side, abnormal shape of erythrocytes (hexagonal/pentagonal/tetragonal), development of lobopodial projections, cell rupture, membrane internalization, and formation of ring-shaped RBC. Energy dispersive X-ray spectroscopy (EDS) showed the presence of a considerable percentage of silicon and lead in erythrocytes of the fish collected from the polluted lake, in contrast to a negligible concentration of the two elements in control fish. Significance of the study in relation to fish health in a polluted body of water and the importance of SEM, EDS, and light microscopy in utilizing hematological parameters as pollution indicators are discussed.
Spectral features of lightning‐induced ion cyclotron waves at low latitudes: DEMETER observations and simulation
Authors: Shklyar D. R. , Storey L. R. O. , Chum J. , Jiříček F. , Němec F. , Parrot M. , Santolik O. , Titova E. E.
Published: October 2012

We use a comprehensive analysis of 6‐component ELF wave data from the DEMETER satellite to study proton whistlers, placing emphasis on low‐latitude events originating from lightning strokes in the hemisphere opposite to the hemisphere of observation. In this case, the formation of proton whistlers does not involve mode conversion caused by a strong mode coupling at a crossover frequency, although a polarization reversal remains an important element in formation of the phenomenon. DEMETER measurements of the six electromagnetic field components in the frequency band below 1000 Hz make it possible to determine not only the dynamic spectrum, but also the wave polarization, the wave normal angle, and the normalized parallel component of the Poynting vector. This permits us to address fine features of proton whistlers, in particular, we show that the deviation of the upper cutoff frequency from the equatorial cyclotron frequency is related to the Doppler shift. Experimental study of proton whistlers is supplemented by an investigation of ion cyclotron wave propagation in a multicomponent magnetoplasma and by numerical modeling of spectrograms, both in the frame of geometrical optics.
Structure of the subduction system in southern Peru from seismic array data
Authors: Phillips Kristin , Clayton Robert W. , Davis Paul , Tavera Hernando , Guy Richard , Skinner Steven , Stubailo Igor , Audin Laurence , Aguilar Victor
Published: October 2012

The subduction zone in southern Peru is imaged using converted phases from teleseismic P, PP, and PKP waves and Pwave tomography using local and teleseismic events with a linear array of 50 broadband seismic stations spanning 300 km from the coast to near Lake Titicaca. The slab dips at 30° and can be observed to a depth of over 200 km. The Moho is seen as a continuous interface along the profile, and the crustal thickness in the back‐arc region (the Altiplano) is 75 km thick, which is sufficient to isostatically support the Andes, as evidenced by the gravity. The shallow crust has zones of negative impedance at a depth of 20 km, which is likely the result of volcanism. At the midcrustal level of 40 km, there is a continuous structure with a positive impedance contrast, which we interpret as the western extent of the Brazilian Craton as it underthrusts to the west.Vp/Vs ratios estimated from receiver function stacks show average values for this region with a few areas of elevated Vp/Vs near the volcanic arc and at a few points in the Altiplano. The results support a model of crustal thickening in which the margin crust is underthrust by the Brazilian Shield.