bluuebunny/crossref_metadata_2025 huggingface dataset:
One‐Pot Glycosylations in the Synthesis of Human Milk Oligosaccharides
Authors: Arboe Jennum Camilla , Hauch Fenger Thomas , Bruun Linda M. , Madsen Robert
Published: April 2014

Human milk oligosaccharides contain a well‐defined core structure that makes them interesting synthetic targets for one‐pot glycosylation strategies. In this investigation, a one‐pot procedure was studied in which a galactose thioglycoside is coupled chemoselectively to a phthalimide‐protected glucosamine thioglycoside, and the resulting disaccharide is then coupled to the 3′‐position in lactose. Very high yields of the tetrasaccharide product can be obtained when a protected lactosamine thioglycoside is formed in the first coupling. In contrast, it was not possible to extend the one‐pot process to the synthesis of the corresponding 3″‐linked structures, due to an inefficient synthesis of the lacto‐N‐biose thioglycoside in the first glycosylation. This is explained by the reactivity difference between the 3‐ and 4‐positions in phthalimide‐protected glucosamine. The one‐pot procedure has been applied in an efficient synthesis of the pentasaccharide lacto‐N‐neofucopentaose I, which is composed of N‐acetyllactosamine, lactose, and fucose. On the other hand, a stepwise approach was found to be the preferred synthetic pathway for preparation of the isomeric lacto‐N‐fucopentaose I, which contains a lacto‐N‐biose moiety.
Swine manure char as an adsorbent for mitigation of p‐cresol
Authors: Fitzgerald Sterling , Kolar Praveen , Classen John , Boyette Mike , Das Lalitendu
Published: April 2014

There is a significant interest in synthesizing inexpensive adsorbents for mitigating pollutants emitted from animal agriculture industry such as p‐cresol. Biochar, a byproduct obtained from thermochemical biomass processing is one such source of adsorbent materials. However, presently there is not enough quantitative information on adsorption of p‐cresol on biochar. Hence, the goal of this research is to investigate swine manure char as an inexpensive adsorbent for removal of p‐cresol from an aqueous system. Swine manure was gasified for 15 min at 704°C to obtain gasified manure char. The char was characterized using physical and chemical techniques. Batch experiments were performed in duplicates at 25°C, 35°C, and 45°C to determine the adsorption isotherms and kinetics. Results indicated that gasification enhanced surface area and acid value of manure from 11.42 ± 0.20 to 49.12 ± 0.79 m2 g−1 and 7.81 ± 0.05 to 8.57 ± 0.01, respectively. The enhanced basicity of the resultant char promoted chemisorption of p‐cresol on char surface with maximum adsorption capacities of 7.63 mg g−1 (25°C), 14.99 mg g−1 (35°C), and 14.84 mg g−1 (45°C). Langmuir and Freundlich models suggested that adsorption of p‐cresol on char was favorable. Kinetic analysis of the data also confirmed chemisorption of p‐cresol while the analysis of transport processes suggested that internal diffusion of p‐cresol within the pores was the rate‐limiting step. Use of biochar as an adsorbent for p‐cresol will add value to gasification byproducts and simultaneously reduce water and air pollution associated with swine farming operations. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 125–131, 2015
Improved conservative level set method
Authors: Zhao Lanhao , Bai Xin , Li Tongchun , Williams J. J. R.
Published: April 2014

The standard level set (LS) method can capture the interface smoothly and gives accurate normal vectors but suffers from an excessive amount of mass gain/loss. The conservative LS method exhibits excellent mass conservation properties, but the result is usually contaminated by inaccurate interface normal vectors. To address this problem, the improved conservative LS method is proposed to capture the interface smoothly with excellent mass conservation properties. The improvement of the method lies in that the surface normal is computed from a signed distance function, which is also advected and reinitialized in the flow fields, instead of using the Heaviside function. The proposed method is implemented by implicit two‐step Taylor–Galerkin approximation within the finite element context. The approach is validated with the well‐known benchmark problems and is found out to be highly reliable and accurate. Copyright © 2014 John Wiley & Sons, Ltd.
The Effects of Disaggregation on Forecasting Nonstationary Time Series
Authors: Poncela Pilar , García‐Ferrer Antonio
Published: April 2014

This paper focuses on the effects of disaggregation on forecast accuracy for nonstationary time series using dynamic factor models. We compare the forecasts obtained directly from the aggregated series based on its univariate model with the aggregation of the forecasts obtained for each component of the aggregate. Within this framework (first obtain the forecasts for the component series and then aggregate the forecasts), we try two different approaches: (i) generate forecasts from the multivariate dynamic factor model and (ii) generate the forecasts from univariate models for each component of the aggregate. In this regard, we provide analytical conditions for the equality of forecasts.

The results are applied to quarterly gross domestic product (GDP) data of several European countries of the euro area and to their aggregated GDP. This will be compared to the prediction obtained directly from modeling and forecasting the aggregate GDP of these European countries. In particular, we would like to check whether long‐run relationships between the levels of the components are useful for improving the forecasting accuracy of the aggregate growth rate. We will make forecasts at the country level and then pool them to obtain the forecast of the aggregate. The empirical analysis suggests that forecasts built by aggregating the country‐specific models are more accurate than forecasts constructed using the aggregated data. Copyright © 2014 John Wiley & Sons, Ltd.
Theoretical Investigation of Waste Heat Recovery from an IC Engine Using Vapor Absorption Refrigeration System and Thermoelectric Converter
Authors: Sonthalia Ankit , Reddy Somesh , Kumar C. Ramesh , Kamani Keval
Published: April 2014

This study proposes the preliminary simulation of a single cylinder spark ignition engine with waste heat recovery system. To harvest waste heat energy from the engine exhaust a thermoelectric generator coupled to a vapor absorption refrigeration (VAR) system was proposed in this simulation work. Parametric simulation of engine, thermoelectric generator and VAR using thermodynamic relations was carried out in MATLAB – Simulink software. An attempt has been made mathematically to integrate engine, thermoelectric generator and VAR system to study the effect of engine load, speed, equivalence ratio on thermoelectric output and coefficient of performance (COP) of a VAR system. In this study, the VAR system runs by taking heat energy from the exhaust gas and the electric power produced by a thermoelectric generator was utilized to run the pump of the refrigeration system. It was found that COP of the absorption refrigeration system depends on engine load, speed and air fuel equivalence ratio. The study also reveals that about 10% to 15% of the total exhaust energy can be harvested using this system.
The function of wisdom dimensions in ego‐identity development among Chinese university students
Authors: Bang Hyeyoung , Zhou Yuchun
Published: April 2014

This study investigates the relationship between wisdom and ego‐identity among university students in China. Using Marcia's ego‐identity statuses and Ardelt's wisdom dimensions as the theoretical and conceptual framework, the study investigates 356 university students in China. After exploratory and confirmatory factor analyses, four factors from wisdom and five factors from ego‐identity were retrieved. A structural equation model was then conducted to analyse the relationships. The findings were: (1) among wisdom dimensions, cognitive, and reflective wisdom, especially perspective‐taking best predicted achievement, (2) all three dimensions of wisdom predicted moratorium, but reflective wisdom was the most pronounced predictor, (3) all three dimensions of wisdom predicted diffusion, but resentment items from reflective wisdom were the most pronounced predictors, and (4) gender was a significant predictor of ego‐identity achievement and diffusion. These findings suggest that efforts to build reflective wisdom might contribute to healthier ego‐identity formation.
Clinical translation of animal models of treatment relapse
Authors: Pritchard Duncan , Hoerger Marguerite , Mace F. Charles , Penney Heather , Harris Brian
Published: April 2014

Behavioral Momentum Theory (BMT) has inspired animal models of treatment relapse. We translated the models of reinstatement and resurgence into clinical procedures to test whether relapse tests would replicate behavior pattern found in basic research. Following multiple schedule baseline reinforcement of a 16‐year‐old male's problem behavior at equal rates by two therapists, treatment was introduced using a variable‐interval, variable‐time (VI VT) schedule arrangement with therapists delivering reinforcers at different rates. Despite the differing rates of VI VT reinforcers, the treatment produced comparable reductions in problem behavior. Following successful treatment, the two therapists discontinued treatment and resumed reinforcement of problem behavior at equal rates that constituted a reinstatement of baseline conditions. As predicted by BMT, reinstatement resulted in an immediate return of high rates of problem behavior but was 2.6 times higher for the therapist using the higher rate VI VT treatment. A second treatment phase was implemented followed by a test of resurgence in a single extended extinction session conducted separately for each therapist. The unequal VI VT treatment rates by therapists resulted in 2.1 times greater responding in the resurgence test for the therapist who implemented the higher rate VI VT procedure. These results are consistent with basic research studies and BMT.
Immunocytological detection of salivary mucins (MUC5B) on the mucosal pellicle lining human epithelial buccal cells
Authors: Morzel Martine , Siying Tai , Brignot Hélène , Lherminier Jeannine
Published: April 2014

The mucosal pellicle is defined as the protein film adsorbed onto oral mucosa. This study aimed at characterizing the ultrastructure of human epithelial buccal cells and localizing salivary mucins MUC5B, a major constituent of the mucosal pellicle. Cells were sampled from the buccal surface and prepared for Transmission Electron Microscopy using high‐pressure freezing/cryosubstitution followed by immunogold labelling of MUC5B. Morphologically, cells were visualized as typical cells of the superficial layer of a squamous nonkeratinized epithelium with a partly degraded plasma membrane. The outer surface of the plasma membrane was lined with a biological material of medium electron density. MUC5B were detected in the extracellular space, and particularly in the vicinity of the plasma membrane, sometimes onto fibrils protruding from the membrane. This area was, therefore, considered as constituting the mucosal pellicle, which appeared as a mixed film of both salivary and epithelial components. The distribution of gold particles suggested that the surface of the pellicle was not uniform, and that the film thickness could reach up to 100 nm. This work showed the feasibility of visualizing and characterizing the mucosal pellicle directly on human epithelial buccal cells sampled in a noninvasive manner. Microsc. Res. Tech. 77:453–457, 2014. © 2014 Wiley Periodicals, Inc.
Development and validation of a recurrent Clostridium difficile risk‐prediction model
Authors: Zilberberg Marya D. , Reske Kimberly , Olsen Margaret , Yan Yan , Dubberke Erik R.
Published: April 2014

BACKGROUND

Recurrent Clostridium difficile infection (rCDI) affects 10% to 25% of patients with initial CDI (iCDI). Initiation of new therapies that reduce recurrences rests on identifying patients at high risk for rCDI at iCDI onset.

OBJECTIVE

To develop a predictive model for rCDI based on factors present at iCDI onset.

DESIGN

Retrospective cohort study.

SETTING

Large urban academic medical center.

PATIENTS

All adult patients with an inpatient iCDI from January 1, 2003 to December 31, 2009.

INTERVENTION

None.

MEASUREMENTS

Positive toxin assay for C difficile with no C difficile infection in the previous 60 days constituted iCDI. Repeat positive toxin within 42 days of stopping iCDI treatment defined rCDI. Three demographic, 13 chronic, and 12 acute disease characteristics, and 7 processes of care prior to or at the onset of iCDI, were assessed for association with rCDI. A logistic regression model to identify predictors for rCDI was developed and cross‐validated.

RESULTS

Among the 4196 patients enrolled, 425 (10.1%) developed rCDI. Six factors (case status as community‐onset healthcare‐associated, ≥2 hospitalizations in the prior 60 days, new gastric acid suppression, fluoroquinolone and high‐risk antibiotic use at the onset of iCDI, age) predicted rCDI in multivariate analyses, whereas intensive care unit stay appeared protective. The model achieved moderate discrimination (C statistic 0.643) and calibration (Brier score 0.089). Its negative predictive value was 90% or higher across a wide range of risk.

CONCLUSIONS

Among patients hospitalized with rCDI, multiple factors present at the onset of iCDI increased the risk for rCDI. Recognizing patients at high‐risk for rCDI can help clinicians tailor early treatment and prevention. Journal of Hospital Medicine 2014;9:418–423. © 2014 Society of Hospital Medicine
Registration of in vivo prostate MRI and pseudo‐whole mount histology using Local Affine Transformations guided by Internal Structures (LATIS)
Authors: Kalavagunta Chaitanya , Zhou Xiangmin , Schmechel Stephen C. , Metzger Gregory J.
Published: April 2014

Purpose

To present a novel registration approach called LATIS (Local Affine Transformation guided by Internal Structures) for coregistering post prostatectomy pseudo‐whole mount (PWM) pathological sections with in vivo MRI (magnetic resonance imaging) images.

Materials and Methods

Thirty‐five patients with biopsy‐proven prostate cancer were imaged at 3T with an endorectal coil. Excised prostate specimens underwent quarter mount step‐section pathologic processing, digitization, annotation, and assembly into a PWM. Manually annotated macro‐structures on both pathology and MRI were used to assist registration using a relaxed local affine transformation approximation. Registration accuracy was assessed by calculation of the Dice similarity coefficient (DSC) between transformed and target capsule masks and least‐square distance between transformed and target landmark positions.

Results

LATIS registration resulted in a DSC value of 0.991 ± 0.004 and registration accuracy of 1.54 ± 0.64 mm based on identified landmarks common to both datasets. Image registration performed without the use of internal structures led to an 87% increase in landmark‐based registration error. Derived transformation matrices were used to map regions of pathologically defined disease to MRI.

Conclusion

LATIS was used to successfully coregister digital pathology with in vivo MRI to facilitate improved correlative studies between pathologically identified features of prostate cancer and multiparametric MRI. J. Magn. Reson. Imaging 2015;41:1104–1114. © 2014 Wiley Periodicals, Inc.
Numerical optimization of a waveguide transition using finite element beam propagation
Authors: Dörfler Willy , Findeisen Stefan
Published: April 2014

We consider a waveguide with principal guiding direction for which the beam propagation method is applicable. A simulation method based on an FEM for Maxwell's equation with 3D Nedelec elements is developed. The power loss of the waveguide is minimized by varying a finite number of shape parameters. We validate the method by comparing our findings to some published results. Copyright © 2014 John Wiley & Sons, Ltd.
Changes in macrophage phenotype and induction of epithelial‐to‐mesenchymal transition genes following acute Achilles tenotomy and repair
Authors: Sugg Kristoffer B. , Lubardic Jovan , Gumucio Jonathan P. , Mendias Christopher L.
Published: April 2014

Tendon injuries occur frequently in physically active individuals, but the clinical outcomes for these injuries can be poor. In many injured tissues the repair process is orchestrated by two types of cells, macrophages and fibroblasts. Macrophages, which have both pro‐inflammatory (M1) and anti‐inflammatory (M2) phenotypes, can directly participate in tissue remodeling and direct the response of other cells through the secretion of cytokines and growth factors. In many organ systems, epithelial cells can trans‐differentiate into fibroblasts, which can then regenerate damaged ECM. This process is triggered via activation of epithelial‐to‐mesenchymal transition (EMT) signaling programs. Most tendons are surrounded by sheets of epithelial cells, and these tissue layers could provide a source of fibroblasts to repair injured tendons. To gain greater insight into the biology of tendon repair, we performed a tenotomy and repair in Achilles tendons of adult rats and determined changes in macrophage phenotype, and ECM‐ and EMT‐related genes over a 4‐week time course. The results from this study suggest that changes in macrophage phenotype and activation of EMT‐related programs likely contribute to the degradation and subsequent repair of injured tendon tissue. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:944–951, 2014.
Anger: Cause or Consequence of Posttraumatic Stress? A Prospective Study of Dutch Soldiers
Authors: Lommen Miriam J. J. , Engelhard Iris M. , van de Schoot Rens , van den Hout Marcel A.
Published: April 2014

Many studies have shown that individuals with posttraumatic stress disorder (PTSD) experience more anger over time and across situations (i.e., trait anger) than trauma‐exposed individuals without PTSD. There is a lack of prospective research, however, that considers anger levels before trauma exposure. The aim of this study was to prospectively assess the relationship between trait anger and PTSD symptoms, with several known risk factors, including baseline symptoms, neuroticism, and stressor severity in the model. Participants were 249 Dutch soldiers tested approximately 2 months before and approximately 2 months and 9 months after their deployment to Afghanistan. Trait anger and PTSD symptom severity were measured at all assessments. Structural equation modeling including cross‐lagged effects showed that higher trait anger before deployment predicted higher PTSD symptoms 2 months after deployment (β = .36), with stressor severity and baseline symptoms in the model, but not with neuroticism in the model. Trait anger at 2 months postdeployment did not predict PTSD symptom severity at 9 months, and PTSD symptom severity 2 months postdeployment did not predict subsequent trait anger scores. Findings suggest that trait anger may be a pretrauma vulnerability factor for PTSD symptoms, but does not add variance beyond the effect of neuroticism.
Synthesis and Characterization of Homopolymers Bearing Acid‐Cleavable Cationic Side‐Chains for pH‐Modulated Release of DNA
Authors: Xu Zhangyan , Lai Junping , Tang Rupei , Ji Weihang , Wang Rui , Wang Jun , Wang Chun
Published: April 2014

A new type of homopolymers, PMAOE, bearing acid‐cleavable cationic side‐chains is synthesized and characterized. PMAOE is obtained via free radical polymerization, and they could efficiently bind and condense plasmid DNA at neutral pH. The strength of DNA binding is dependent on the length of PMAOE chains. NMR analysis reveals that hydrolysis of the ortho ester group of PMAOE follows an exocyclic mechanism and the rate of hydrolysis is much accelerated at mildly acidic pH, leading to accelerated disruption of polyplexes and release of DNA in mildly acidic environment. PMAOE is not toxic to cultured NIH 3T3 and COS‐7 cells measured by MTT. This study demonstrates a unique mechanism of achieving pH‐modulated binding and release of DNA from polymers with potential applications for gene delivery.
Controlled Synthesis and Self‐Assembly of Dopamine‐Containing Copolymer for Honeycomb‐Like Porous Hybrid Particles
Authors: Wang Jinling , Zhu Hui , Chen Gaojian , Hu Zhijun , Weng Yuyan , Wang Xinbo , Zhang Weidong
Published: April 2014

Dopamine‐containing monomers, N‐3,4‐dihydroxybenzenethyl methacrylamide (DMA) and dimethylaminoethyl methacrylate (DMAEMA), are successfully copolymerized in a well‐controlled manner via ambient temperature single‐electron transfer initiation and propagation through the radical addition fragmentation chain transfer (SET‐RAFT) method. The controlled behaviors of the copolymerization are confirmed by the first‐order kinetic plots, the linear relationships between molecular weights, and the monomer conversions while keeping relatively narrow molecular weight distribution (Mw/Mn ≤ 1.45). Moreover, biomimetic self‐assembly of poly(N‐3,4‐dihydroxybenzenethyl methacrylamide‐co‐dimethylaminoethyl methacrylate) PDMA‐co‐PDMAEMA and inorganic particles are employed to prepare tunable honeycomb‐like porous hybrid particles (HPHPs) by regulating the predesigned chemical composition. In addition, the inorganic sacrificial templates are successfully selective etched for the formation of porous organic materials.

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Free‐Standing, Single‐Bilayer‐Thick Polymeric Nanosheets via Spatially Confined Polymerization
Authors: Qin Haili , Wang Dong , Xiong Xiong , Jin Jian
Published: April 2014

Polymeric nanosheets organized by molecular building blocks bearing specifically oriented reactive groups provide abundant and versatile strategies for tailoring structure and chemical functionality periodically over extended length scales that complement graphene. Here we report the bulk synthesis of free‐standing polymeric nanosheets via spatially confined polymerization from an elaborate 2D supramolecular system composed of two liquid‐crystalline lamellar bilayer membranes of a self‐assembled nonionic surfactant—dodecylglyceryl itaconate (DGI)—sandwiched by a water layer. By employing a covalent polymerization on the lamellar bilayer membranes, single‐bilayer‐thick (4.2 nm), and large area (greater than 100 μm2) polymeric nanosheets of bilayer membranes are achieved. The polymeric nanosheets could serve as a well‐defined 2D platform for post‐functionalization for producing advanced hybrid materials by introducing the reactions on the hydroxyl groups at the head of DGI on the outer surfaces.

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The Guanidinium Group as a Key Part of Water‐Soluble Polymer Carriers for siRNA Complexation and Protection against Degradation
Authors: Tabujew Ilja , Freidel Christoph , Krieg Bettina , Helm Mark , Koynov Kaloian , Müllen Klaus , Peneva Kalina
Published: April 2014

Here, the preparation of a novel block copolymer consisting of a statistical copolymer N‐(2‐hydroxypropyl) methacrylamide‐s‐N‐(3‐aminopropyl) methacrylamide and a short terminal 3‐guanidinopropyl methacrylamide block is reported. This polymer structure forms neutral but water‐soluble nanosized complexes with siRNA. The siRNA block copolymer complexes are first analyzed using agarose gel electrophoresis and their size is determined with fluorescence correlation spectroscopy. The protective properties of the polymer against RNA degradation are investigated by treating the siRNA block copolymer complexes with RNase V1. Heparin competition assays confirm the efficient release of the cargo in vitro. In addition, the utilization of microscale thermophoresis is demonstrated for the determination of the binding strength between a fluorescently labeled polyanion and a polymer molecule.

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Taxonomic and functional profiles of soil samples from Atlantic forest and Caatinga biomes in northeastern Brazil
Authors: Pacchioni Ralfo G. , Carvalho Fabíola M. , Thompson Claudia E. , Faustino André L. F. , Nicolini Fernanda , Pereira Tatiana S. , Silva Rita C. B. , Cantão Mauricio E. , Gerber Alexandra , Vasconcelos Ana T. R. , Agnez‐Lima Lucymara F.
Published: April 2014

Although microorganisms play crucial roles in ecosystems, metagenomic analyses of soil samples are quite scarce, especially in the Southern Hemisphere. In this work, the microbial diversity of soil samples from an Atlantic Forest and Caatinga was analyzed using a metagenomic approach. Proteobacteria and Actinobacteria were the dominant phyla in both samples. Among which, a significant proportion of stress‐resistant bacteria associated to organic matter degradation was found. Sequences related to metabolism of amino acids, nitrogen, and DNA and stress resistance were more frequent in Caatinga soil, while the forest sample showed the highest occurrence of hits annotated in phosphorous metabolism, defense mechanisms, and aromatic compound degradation subsystems. The principal component analysis (PCA) showed that our samples are close to the desert metagenomes in relation to taxonomy, but are more similar to rhizosphere microbiota in relation to the functional profiles. The data indicate that soil characteristics affect the taxonomic and functional distribution; these characteristics include low nutrient content, high drainage (both are sandy soils), vegetation, and exposure to stress. In both samples, a rapid turnover of organic matter with low greenhouse gas emission was suggested by the functional profiles obtained, reinforcing the importance of preserving natural areas.
Nuclear and cytoplasmic differentiation among Mediterranean populations of Bemisia tabaci: testing the biological relevance of cytotypes
Authors: Terraz Gabriel , Gueguen Gwenaelle , Arnó Judit , Fleury Frédéric , Mouton Laurence
Published: April 2014

BACKGROUND

The taxonomy of the species complex Bemisia tabaci is still an unresolved issue. Recently, phylogenetic analysis based on mtCOI identified 31 cryptic species. However, mitochondrial diversity is observed within these species, associated with distinct symbiotic bacterial communities forming associations, which here are called cytotypes. The authors investigated the biological significance of two cytotypes (Q1 and Q2) belonging to the Mediterranean species, which have only been found in allopatry in the Western Mediterranean to date. Sampling was done over a few years in Western Europe, and sympatric situations were found that allowed their reproductive compatibility to be tested in the field with the use of microsatellites.

RESULTS

The field survey indicated that, in spite of its recent introduction, Q2 is well established in France and Spain, where it coexists with Q1. Microsatellite data showed that, in allopatry, Q1 and Q2 are highly differentiated, while there is little or no genetic differentiation when they coexist in sympatry, suggesting a high rate of hybridisation. Crossing experiments in the lab confirmed their interfertility.

CONCLUSION

Q1 and Q2 hybridise, which confirms that they belong to the same species, in spite of the high degree of genetic differentiation at both the cytoplasmic and nuclear levels, and also suggests that their symbiotic bacteria do not prevent hybridisation. © 2014 Society of Chemical Industry
Biology and management of Bemisia whitefly vectors of cassava virus pandemics in Africa
Authors: Legg James P , Shirima Rudolph , Tajebe Lensa S , Guastella Devid , Boniface Simon , Jeremiah Simon , Nsami Elibariki , Chikoti Patrick , Rapisarda Carmelo
Published: April 2014

Cassava mosaic disease and cassava brown streak disease are caused by viruses transmitted by Bemisia tabaci and affect approximately half of all cassava plants in Africa, resulting in annual production losses of more than $US 1 billion. A historical and current bias towards virus rather than vector control means that these diseases continue to spread, and high Bemisia populations threaten future virus spread even if the extant strains and species are controlled. Progress has been made in parts of Africa in replicating some of the successes of integrated Bemisia control programmes in the south‐western United States. However, these management efforts, which utilise chemical insecticides that conserve the Bemisia natural enemy fauna, are only suitable for commercial agriculture, which presently excludes most cassava cultivation in Africa. Initiatives to strengthen the control of B. tabaci on cassava in Africa need to be aware of this limitation, and to focus primarily on control methods that are cheap, effective, sustainable and readily disseminated, such as host‐plant resistance and biological control. A framework based on the application of force multipliers is proposed as a means of prioritising elements of future Bemisia control strategies for cassava in Africa. © 2014 Society of Chemical Industry
An evaluation of three predatory mite species for the control of greenhouse whitefly (Trialeurodes vaporariorum)
Authors: Medd Nathan C , GreatRex Richard M
Published: April 2014

BACKGROUND

Within integrated pest control programmes, the use of high mite inoculations to control hot spots of whitefly is desirable for many growers. In this experiment, two species of predatory mites established as commercial biological control agents, Typhlodromips montdorensis and Amblyseius swirskii (Acari: Phytoseiidae), were compared with another, more recently introduced species, Amblydromalus limonicus, for their ability to control dense populations of greenhouse whitefly (Trialeurodes vaporariorum) on cucumber plants (Cucumis sativus).

RESULTS

Mite formulation type had a significant effect on the number of mites found on plants, but this did not correspond to increased whitefly control. Plots treated with A. limonicus or T. montdorensis, applied as loose product, had significantly reduced whitefly populations throughout the trial. Analysis showed that no species was observed more often on leaves with higher whitefly densities than on those with lower densities.

CONCLUSION

No species was clearly identified as a suitable candidate for treatment of high‐density whitefly colonies, but results suggest the highest level of predation in A. limonicus. Strategies for the effective use of these predatory mite species in control programmes are discussed. © 2014 Society of Chemical Industry
Ultrasonic‐assisted mist chemical vapor deposition of II‐oxide and related oxide compounds
Authors: Fujita Shizuo , Kaneko Kentaro , Ikenoue Takumi , Kawaharamura Toshiyuki , Furuta Mamoru
Published: April 2014

Basic concepts of ultrasonic‐assisted mist chemical vapor deposition (CVD), and its applications to the fabrication of II‐oxide and related oxide films are described. Fairly good thin film properties and device performance, compared to those achieved by conventional vacuum‐based processes, encourage the mist CVD as a simple, inexpensive, energy‐saving and non‐vacuum process, opening new and wide application of oxide materials for novel devices supporting the future environment. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of large diameter ZnTe single crystals by the double crucible liquid encapsulated pulling method
Authors: Asahi Toshiaki , Sato Kenji
Published: April 2014

In our work, large diameter ZnTe single crystals were grown by various melt growth methods. By a liquid encapsulated vertical gradient freezing method, crystals with large grains and low dislocation density were obtained. By a liquid encapsulated Kyropoulos method, 80 mm diameter crystals were successfully grown from ZnTe seed crystals. However, crystals grown by the both methods had large strain and cracks owing to difference in coefficient of thermal expansion between an encapsulant and ZnTe. Therefore, a new crystal growth method was developed. Two crucibles were used in the new method. It was named double crucible liquid encapsulated pulling method. Crystals up to 100 mm in diameter and 40 mm in length were reproducibly obtained. Both <100> and <110> crystals were successfully grown. The etch pit density of the grown crystal was lower than 10,000 cm–2 and any large strain or cracks were not observed. In order to reduce Te inclusions, wafer annealing was examined. Most Te inclusions were eliminated with suitable Zn pressure and annealing temperature. Optical transparency of the ZnTe crystal increased after annealing. This is because scatter of the incident light by Te inclusions decreased. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of solar cell using II‐III‐VI compound thin film fabricated by conventional sputtering process
Authors: Deguchi H.
Published: April 2014

In order to achieve low cost solar cells, a novel type multinary compound thin film solar cell using ZnInS (II‐III‐VI) thin film as n‐type layer and other layer fabricated by the conventional sputtering process were realized. An AgInTe/ZnInS thin film solar cell fabricated by the conventional sputtering process showed the conversion efficiency is 1.1%. In this study, p‐type materials suitable for ZnInS and doping ZnInS with additive elements such as IIa (Ca,Sr) and VIb (O) group elements were investigated to improve the characteristics of ZnInS thin film solar cell. As the results, the best conversion efficiency of 2.8% was obtained CuInGaSe/CaZnInS thin film solar cell. This value is superior to that of AgInTe/ZnInS thin film solar cell by 2.5 times. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identification of recombination centers responsible for reduction of energy conversion efficiency in CdTe‐based solar cells
Authors: Karczewski G. , Chusnutdinow S. , Olender K. , Wosiński T. , Wojtowicz T.
Published: April 2014

In this work we discuss experimental data which can explain reasons for the limited energy conversion efficiencies observed in monocrystalline, thin‐film CdTe‐based solar cells grown molecular beam epitaxy. Two kinds of samples has been investigated and discussed – p‐ and n‐type doped CdTe layers with metallic Schottky barriers and p‐i‐n heterojunctions (p‐ZnTe/i‐CdTe/n‐CdTe solar cells). Both kinds of junctions exhibit strong rectifying properties with the rectifying coefficient exceeding 105 at 300 K and +/– 1 V. Photovoltaic properties of the solar cells have been determined by I–V measurements under illumination and by spectral characteristics of photocurrent. Based on the spectral measurements it was found that the p‐ZnTe/i‐CdTe/n‐CdTe diodes are sensitive to illumination within the 550–850 nm wavelength range confirming their applicability for solar energy conversion. I–V characteristics measured at 1‐sun illumination yield relatively low energy conversion efficiencies below 4.9%. In order to determine the origin of the limited efficiency in the CdTe‐based solar cells (theoretical limit for n‐CdTe/p‐ZnTe solar cells is as high as 20%) the deep level transient spectroscopy (DLTS) technique has been applied. The results of these DLTS studies revealed the presence of deep electron and hole traps. The low‐temperature DLTS peaks can be ascribed to the hole traps in the CdTe absorber. The high‐temperature DLTS peak changes its sign depending on the sign of the filling pulses acting as a majority trap for negative filling pulses and minority trap for positive filling pulses. The estimated activation energies of the majority‐ and minority trap level are equal to 0.74–0.78 eV and 1.05 eV, respectively. The sum of these energies is close to the value of the CdTe energy gap, suggesting that this energy level can be assigned to the recombination center present in the CdTe absorber material. Basing on the logarithmic capture kinetics of the traps detected in the high‐temperature region we assign the recombination center to electronic states of extended defects, probably threading dislocations. Very similar DLTS results obtained for CdTe Schottky barriers confirm the conclusion. Thus, we conclude that not the point defects but rather extended defect are responsible for the limited energy conversion efficiency in CdTe‐based solar cells.
Nonreciprocal magneto‐optical effects in quantum wells
Authors: Kochereshko V. , Kats V. , Platonov A. , Sapega V. , Besombes L. , Wolverson D. , Mariette H.
Published: April 2014

In this paper we predicted and observed a new magneto‐optical effect – the “effect of parity”. The effect is manifest as a redistribution of the oscillator strengths between spatially even and odd center of mass quantized states of the exciton in the quantum well. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of acceptor co‐doping on magnetism and electronic states in ferromagnetic semiconductor (Zn,Cr)Te
Authors: Zhang Ke , Akiyama Ryota , Kanazawa Ken , Kuroda Shinji , Ofuchi Hironori
Published: April 2014

The magnetic properties and the electronic states were investigated for a magnetic semiconductor (Zn,Cr)Te co‐doped nitrogen (N) as an acceptor impurity. A series of N‐doped Zn1–xCrxTe thin films with Cr compositions in the range of x = 0.06–0.09 and N concentrations in the range of [N] = 1018–1020 cm–3 were grown by molecular beam epitaxy (MBE), and the magnetization measurement using superconducting quantum interference device (SQUID) magnetometer and the X‐ray absorption fine structure (XAFS) measurements were performed. As a result, the disappearance of ferromagnetic behaviors and the change in X‐ray absorption near edge structure (XANES) spectra were observed at almost the same nitrogen concentration around [N] = 1 × 1020 cm–3. This correlated change in the magnetic properteis and the Cr electronic states was discussed in relation to a decrease of the electron density in the 3d impurity level due to the N co‐doping. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dendritic TiO2/ln2S3/AgInS2 Trilaminar Core–Shell Branched Nanoarrays and the Enhanced Activity for Photoelectrochemical Water Splitting
Authors: Liu Zhifeng , Guo Keying , Han Jianhua , Li Yajun , Cui Ting , Wang Bo , Ya Jing , Zhou Cailou
Published: April 2014

Hierarchical TiO2/ln2S3/AgInS2 trilaminar core–shell branched nanorod arrays (T‐CS BNRs) have been fabricated directly on conducting glass substrates (FTO) via a facile, versatile and low‐cost hydrothermal and successive ionic layer adsorption and reaction (SILAR) for photoelectrochemical (PEC) water splitting. On the basis of optimal thickness of AgInS2 shell, such TiO2/ln2S3/AgInS2 T‐CS BNRs exhibit a higher photocatalytic activity, the photocurrent density and efficiency for hydrogen generation are up to 22.13 mA·cm−2 and 14.83%, which is, to the best of our knowledge, the highest value ever reported for similar nanostructures. The trilaminar architecture is able to suppress carrier recombination and increase electron collection efficiency via (i) increasing the photon absorption through the lager specific surface area of TiO2 BNRs and a sensitizer layer (AgInS2), (ii) a buffer layer (ln2S3), (iii) a better energy level alignment.
Further insights into diastolic dysfunction in first‐trimester trisomy‐21 fetuses
Authors: Mula R. , Grande M. , Bennasar M. , Crispi F. , Borobio V. , Martinez J. M. , Gratacos E. , Borrell A.
Published: April 2014

Objective

To assess fetal cardiac function in first‐trimester trisomy‐21 fetuses as compared with fetuses with other aneuploidies, euploid fetuses with cardiac defects or isolated increased nuchal translucency (NT) and controls.

Methods

During a 2.5‐year period, NT, ductus venosus (DV) blood flow, diastolic filling time, early filling time, tricuspid flow, tricuspid and mitral valve E/A velocity ratios, left ventricle shortening fraction, left myocardial performance index and fetal heart rate were assessed in fetuses with a crown–rump length between 45 and 84 mm undergoing chorionic villus sampling at our center. Cardiac parameters among study groups were compared with the use of 95% CIs.

Results

The study population comprised 28 fetuses with trisomy 21, 25 with other aneuploidies, 94 euploid fetuses with abnormal findings (27 with cardiac defects, 31 with other structural anomalies and 36 with isolated increased NT) and 271 controls. Trisomy‐21 fetuses showed signs of diastolic dysfunction such as increased DV pulsatility index and E/A ratios together with a higher prevalence of tricuspid regurgitation. However, no differences were found in euploid fetuses with cardiac defects or isolated increased NT.

Conclusions

No signs of cardiac dysfunction were observed in euploid fetuses with increased NT or cardiac defects, while in trisomy‐21 fetuses signs of diastolic dysfunction could be potentially attributed to volume overload. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.
tRNA synthetase: tRNA aminoacylation and beyond
Authors: Pang Yan Ling Joy , Poruri Kiranmai , Martinis Susan A.
Published: April 2014

The aminoacyl‐tRNA synthetases are prominently known for their classic function in the first step of protein synthesis, where they bear the responsibility of setting the genetic code. Each enzyme is exquisitely adapted to covalently link a single standard amino acid to its cognate set of tRNA isoacceptors. These ancient enzymes have evolved idiosyncratically to host alternate activities that go far beyond their aminoacylation role and impact a wide range of other metabolic pathways and cell signaling processes. The family of aminoacyl‐tRNA synthetases has also been suggested as a remarkable scaffold to incorporate new domains that would drive evolution and the emergence of new organisms with more complex function. Because they are essential, the tRNA synthetases have served as pharmaceutical targets for drug and antibiotic development. The recent unfolding of novel important functions for this family of proteins offers new and promising pathways for therapeutic development to treat diverse human diseases. WIREs RNA 2014, 5:461–480. doi: 10.1002/wrna.1224

This article is categorized under:

RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems

RNA Interactions with Proteins and Other Molecules > RNA–Protein Complexes

Translation > Translation Mechanisms

RNA Processing > tRNA Processing
Criteria for determining breeding‐pair status of male mallards captured in decoy traps
Authors: Brasher Michael G. , Davis J. Brian , Kaminski Matthew R. , Emery Robert B. , Kaminski Richard M. , Baldassarre Guy A.
Published: April 2014

Methods for accurately determining pair status of male ducks during the breeding season are necessary for further understanding the roles of paired and unpaired males in waterfowl breeding populations. Previous studies assigned pair status based on behavioral observations of randomly captured and marked birds, but this method limits control over sample sizes of paired and unpaired individuals. We evaluated 8 criteria for determining breeding‐pair status (i.e., paired, unpaired) of male mallards (Anas platyrhynchos) based on scenarios of capture in decoy traps during late March–early April in Prairie‐Parkland Canada and central New York, USA. Of the 51 males we classified as paired across 3 study sites and years, we confirmed from repeated visual observations that 46 (90%) were indeed paired. All 36 males classified as unpaired were subsequently confirmed to be unpaired. The predicted overall probability of correctly assigning pair status to captured males was 93.7% (95% CI = 86.8–97.3%). These criteria provide an effective yet simple technique to identify pair status of male mallards captured in decoy traps and should enable more efficient use of time and logistical resources in studies requiring samples of paired and unpaired male ducks. © 2014 The Wildlife Society.
Heterocyclic‐2‐thione Derivatives of Silver(I): The Methyl Substituent at N1atom of a Imidazoline‐2‐thione/Imidazolidine‐2‐thione Alters a Dimer [Ag2(HL)4(PPh3)2](NO3)2 into a Monomer [Ag(HL)2(PPh3)](NO3)
Authors: Lobana Tarlok S. , Sultana Razia , Butcher Ray J. , Jasinski Jerry P. , Akitsu Takashiro
Published: April 2014

Reactions of silver(I) nitrate with 1,3‐imidazolidine‐2‐thiones (LI‐NH, LI‐NMe), 1,3‐imidazoline‐2‐thiones (LII‐NH, LII‐NMe), and that of silver(I) acetate with thiazolidine‐2‐thione (LIII‐NH), or benz‐imidazoline‐2‐thione (LIV‐NH) and triphenylphosphine (PPh3) as co‐ligand (1:2:2 molar ratios) in acetonitrile, acetonitrile‐methanol, or acetonitrile‐acetone mixtures have yielded mono‐ and dinuclear complexes of stoichiometry: [Ag2{µ‐(LI‐NH‐S)}2(LI‐NH‐S)2(PPh3)2](NO3)2·2CH3OH (1), [Ag(LI‐NMe‐S)2(PPh3)](NO3) (2), [Ag2{µ‐(LII‐NH‐S)}2(LII‐NH‐S)2(PPh3)2](NO3)2·2CH3OH (3), [Ag(LII‐NMe‐S)2(PPh3)](NO3) (4), [Ag(LIII‐NH‐S)(LIII‐N‐S)(PPh3)2] (5), and [Ag(LIV‐NH‐S)2(PPh3)2](OAc)·H2O (6). In complex 5, one thio ligand is anionic (LIII‐N–), whereas all other complexes have neutral thio ligands bonded to AgI ion. The complexes were characterized using elemental analysis, IR, 1H and 31P NMR spectroscopy and single crystal X‐ray crystallography. It is interesting to note that LI‐NH and LII‐NH ligands formed dinuclear complexes 1 and 3 with four‐coordination around each metal center, whereas the presence of a methyl group at one nitrogen atom (i.e. LI‐NMe and LII‐NMe) yielded mononuclear complexes 2 and 4 with three‐coordination around each metal center. The ligands LIII‐NH and LIV‐NH behaved differently.
Intercalation induced surface cracking in electrode particles
Authors: Raghavan R.S. , Kumar A.M , Narayanrao R.
Published: April 2014

Degradation mechanisms in Li‐ion batteries such as SEI formation, isolation of active material and reduction in electronic conductivity appear to correlate with the increase in surface area of electrode particles caused by particle fracture during charge/discharge cycles. The focus of this study is on the surface cracking of an electrode particle, as large tensile stresses operate on the surface during the delithiation process of charge/discharge cycling. The pre‐existing surface flaws act as crack initiators under this scenario and we discuss the extension of these cracks under two different operating conditions. Approximate analytical expressions for the propensity for surface crack growth is derived in terms of stress intensity factor and fracture toughness of the material. Utilizing dimensional analysis, we arrive at fracture limit diagrams to determine fracture‐free conditions as design guidelines for prescribed electrode particle size or diffusion boundary conditions related to the charging/discharging process. Another significant result of the fracture analysis is that smaller particles can withstand a wider range of fluctuations in concentration or flux at the boundary for surface fracture‐free conditions. This result supplements the conventional understanding that smaller particles show higher structural integrity because of fewer pre‐existing defects.
Optimal regularity for phase transition problems with convection
Authors: Karakhanyan Aram L.
Published: April 2014

In this paper we consider a steady state phase transition problem with given convection

\mathbf v

. We prove, among other things, that the weak solution is locally Lipschitz continuous provided that

\mathbf{v} = D\xi

and

ξ

is a harmonic function. Moreover, for continuous casting problem, i.e. when

\mathbf v

is constant vector, we show that Lipschitz free boundaries are

C^{1}

regular surfaces.