bluuebunny/crossref_metadata_2025 huggingface dataset:
A hindbrain segmental scaffold specifying neuronal location in the adult goldfish, Carassius auratus
Authors: Gilland E. , Straka H. , Wong T.W. , Baker R. , Zottoli S.J.
Published: January 2014

The vertebrate hindbrain develops as a series of well‐defined neuroepithelial segments or rhombomeres. While rhombomeres are visible in all vertebrate embryos, generally there is not any visible segmental anatomy in the brains of adults. Teleost fish are exceptional in retaining a rhombomeric pattern of reticulospinal neurons through embryonic, larval, and adult periods. We use this feature to map more precisely the segmental imprint in the reticular and motor basal hindbrain of adult goldfish. Analysis of serial sections cut in three planes and computer reconstructions of retrogradely labeled reticulospinal neurons yielded a segmental framework compatible with previous reports and more amenable to correlation with surrounding neuronal features. Cranial nerve motoneurons and octavolateral efferent neurons were aligned to the reticulospinal scaffold by mapping neurons immunopositive for choline acetyltransferase or retrogradely labeled from cranial nerve roots. The mapping corresponded well with the known ontogeny of these neurons and helps confirm the segmental territories defined by reticulospinal anatomy. Because both the reticulospinal and the motoneuronal segmental patterns persist in the hindbrain of adult goldfish, we hypothesize that a permanent “hindbrain framework” may be a general property that is retained in adult vertebrates. The establishment of a relationship between individual segments and neuronal phenotypes provides a convenient method for future studies that combine form, physiology, and function in adult vertebrates. J. Comp. Neurol. 522:2446–2464, 2014. © 2014 Wiley Periodicals, Inc.
Statistical analysis of Amenamevir (ASP2151) between pharmacokinetics and clinical efficacies with non‐linear effect model for the treatment of genital herpes
Authors: Takada Akitsugu , Katashima Masataka , Kaibara Atsunori , Sawamoto Taiji , Zhang Wenhui , Keirns James
Published: January 2014

Amenamevir is the international non‐proprietary name for ASP2151 synthesized by Astellas Pharma, Inc. It is a structurally novel class of helicase‐primase inhibitor and demonstrated more potency in vitro anti‐viral activity with low cytotoxicity against varicella‐zoster virus (VZV), herpes simplex virus type 1 (HSV‐1), and herpes simplex virus type 2 (HSV‐2) than acyclovir (ACV). Phase II randomized trial assessed the safety and efficacy of ASP2151 for episodic therapy of recurrent genital herpes was conducted. Participants self‐initiated with ASP2151 (100, 200, or 400 mg daily for 3 days), ASP2151 (1,200 mg as a single dose), placebo for 3 days, or Valacyclovir (500 mg twice daily for 3 days). We present a first population pharmacokinetic (PPK) modeling analysis of Amenamevir for genital herpes patients. The final model retained the effect of Weight and Albumin on CL. Statistical analysis between pharmacokinetics and clinical efficacies was done by using the time above 200 ng/mL (T200). T200 derived from the final PPK model to consider the correlation with Time to lesion healing and viral shedding. This finding suggested that it could be necessary to maintain the Amenamevir concentration above the threshold level to prevent the virus replication.
Intensive removal of signal crayfish (Pacifastacus leniusculus) from rivers increases numbers and taxon richness of macroinvertebrate species
Authors: Moorhouse Tom P. , Poole Alison E. , Evans Laura C. , Bradley David C. , Macdonald David W.
Published: January 2014

Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non‐eradication‐oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates.
Diabetes and immunity to tuberculosis
Authors: Martinez Nuria , Kornfeld Hardy
Published: January 2014

The dual burden of tuberculosis (TB) and diabetes has attracted much attention in the past decade as diabetes prevalence has increased dramatically in countries already afflicted with a high burden of TB. The confluence of these two major diseases presents a serious threat to global public health; at the same time it also presents an opportunity to learn more about the key elements of human immunity to TB that may be relevant to the general population. Some effects of diabetes on innate and adaptive immunity that are potentially relevant to TB defense have been identified, but have yet to be verified in humans and are unlikely to fully explain the interaction of these two disease states. This review provides an update on the clinical and epidemiological features of TB in the diabetic population and relates them to recent advances in understanding the mechanistic basis of TB susceptibility and other complications of diabetes. Issues that merit further investigation — such as geographic host and pathogen differences in the diabetes/TB interaction, the role of hyperglycemia‐induced epigenetic reprogramming in immune dysfunction, and the impact of diabetes on lung injury and fibrosis caused by TB — are highlighted in this review.
Identification and characterization of fish oil supplements based on fatty acid analysis combined with a hierarchical clustering algorithm
Authors: Khoomrung Sakda , Raber Georg , Laoteng Kobkul , Francesconi Kevin A.
Published: January 2014

We report a method for simple screening and quality assessment of fish oil supplements based on fatty acid profiles of 25 commercial fish oil supplements determined by using GC/MS with a hierarchical clustering algorithm. Different fatty acid profiles were obtained for the various fish oil products derived from different sources and processes. The contents of eicosapentaenoic acid (20:5 n‐3) and DHA (22:6 n‐3), and of other specific fatty acids as well, could be used as a chemotaxonomic marker to characterize the fish oils. A hierarchical clustering algorithm was then generated and used to efficiently categorize the fish oil products in terms of fish origin, oil components, and production process.

Identification of fish oil supplements.
Low‐temperature chemical glycerolysis to produce diacylglycerols by heterogeneous base catalyst
Authors: Zhong Nanjing , Deng Xiaoting , Huang Jianrong , Xu Li , Hu Kun , Gao Yongqing
Published: January 2014

The present study aimed to develop a heterogeneous catalysis process for diacylglycerols (DAG) production through low‐temperature chemical glycerolysis. Of the heterogeneous catalysts evaluated, MgO‐supported KOH (KOH–MgO) was found effective for the low‐temperature chemical glycerolysis, and the KOH–MgO was characterized by FT‐IR and powder XRD. Reaction temperature was of paramount importance and 80°C was found necessary to enhance the present reaction. Molar ratio of oil to glycerol at stoichiometric ratio (2:1) gave more DAG formation. 41.8 ± 0.8 wt% of DAG was obtained under these conditions: KOH–MgO concentration 4.5 wt% based on oil, acetone dosage 3:1 (acetone to oil in weight ratio), molar ratio of oil to glycerol 2:1, reaction temperature 80°C and time 12 h.

Practical applications: Heterogeneous catalysis has been recognized as green process, it is advantageous over the homogeneous catalysis in terms of separation and reusability of catalysts. The MgO‐supported KOH catalyst described in this study can effectively catalyze the low‐temperature chemical glycerolysis, it could be considered for practical applications.
The Acrylamide Moiety as an Activated Alkene Component in the Intramolecular Baylis–Hillman Reaction: Facile Synthesis of Functionalized α‐Methylene Lactam and Spirolactam Frameworks
Authors: Basavaiah Deevi , Reddy Guddeti Chandrashekar , Bharadwaj Kishor Chandra
Published: January 2014

A facile strategy for the intramolecular Baylis–Hillman reaction by utilizing an acrylamide moiety as an activated alkene component was developed, which thus provides a convenient protocol for obtaining five‐ and six‐membered α‐methylene lactam and spirolactam derivatives.
anti‐Dioxylation of Cyclohex‐4‐ene‐1,2‐diamine Derivatives: Asymmetric Routes to Hydroxy‐ and Amino‐Substituted Cyclohexane and 7‐Azanorbornane
Authors: Savoia Diego , Balestri Davide , Grilli Stefano , Monari Magda
Published: January 2014

The highly diastereoselective anti‐dioxylation of (1R,2R)‐1,2‐bis[(1S)‐phenylethylamino]cyclohexene was accomplished through epoxidation of the double bond with m‐chloroperbenzoic acid (mCPBA) in the presence of a sulfonic or trihaloacetic acid and ring opening of the epoxide in situ in the presence of sulfonate or carboxylate anions. The two procedures, after basic quenching and reductive removal of the N‐substituents, provide stereoselective access to 2‐exo‐5‐endo‐5‐amino‐7‐azabicyclo[2.2.1]heptan‐2‐ol and 4,5‐diaminocyclohexane‐1,2‐diol, respectively. The different outcomes are explained by differing chair conformations of the protonated diamine‐epoxide intermediates, which undergo ring opening through a preferred anti‐diaxial mechanism.
Quantification of isocyanates and amines in polyurethane foams and coated products by liquid chromatography–tandem mass spectrometry
Authors: Mutsuga Motoh , Yamaguchi Miku , Kawamura Yoko
Published: January 2014

An analytical method for the identification and quantification of 10 different isocyanates and 11 different amines in polyurethane (PUR) foam and PUR‐coated products was developed and optimized. Isocyanates were extracted and derivatized with di‐n‐butylamine, while amines were extracted with methanol. Quantification was subsequently performed by liquid chromatography–tandem mass spectrometry. Using this methodology, residual levels of isocyanates and amines in commercial PUR products were quantified. Although the recoveries of certain isocyanates and amines were low, the main compounds used as monomers in the production of PUR products, and their decomposition species, were clearly identified at quantifiable levels. 2,4‐ and 2,6‐toluenediisocyanate were detected in most PUR foam samples and a pastry bag in the range of 0.02–0.92 mg/kg, with their decomposition compounds, 2,4‐ and 2,6‐toluenediamine, detected in all PUR foam samples in the range of 9.5–59 mg/kg. PUR‐coated gloves are manufactured using 4,4′‐methylenebisphenyl diisocyanate as the main raw material, and a large amount of this compound, in addition to 4,4′‐methylenedianiline and dicyclohexylmethane‐4,4′‐diamine were found in these samples.
Influence of the K‐, Na‐ and K‐Na‐carbonate additions during the CO2 chemisorption on lithium oxosilicate (Li8SiO6)
Authors: Romero‐Ibarra Issis C. , Durán‐Muñoz Fernando , Pfeiffer Heriberto
Published: January 2014

Lithium oxosilicate (Li8SiO6) was synthesized and mechanically mixed with potassium carbonate, sodium carbonate, or a mixture of both. While the product sample composition was characterized using X‐ray diffraction, the CO2 chemisorption was evaluated using dynamic (30–800 °C), isothermal (350–650 °C) and cyclic thermogravimetric analyses. The presence of the K, Na, or K‐Na‐carbonates in Li8SiO6 changes the sorption properties in a wide temperature range. K‐, Na‐, K‐Na‐Li8SiO6 samples captured a maximum weight of 32 wt% at 400 °C, 42 wt% at 550 °C, and 38 wt% at 600 °C, respectively. The results revealed that the weight gained on Li8SiO6 mixed with K‐, Na‐ and K‐Na‐carbonates was attributed to the formation of the eutectic phases. These materials would be suitable for CO2 capture over a wide temperature range depending on the application process. Nevertheless, the cyclic experiments showed important variations in their respective efficiencies, depending on the temperature.
Dissociable identity‐ and modality‐specific neural representations as revealed by cross‐modal nonspatial inhibition of return
Authors: Chi Yukai , Yue Zhenzhu , Liu Yupin , Mo Lei , Chen Qi
Published: January 2014

There are ongoing debates on whether object concepts are coded as supramodal identity‐based or modality‐specific representations in the human brain. In this fMRI study, we adopted a cross‐modal “prime–neutral cue–target” semantic priming paradigm, in which the prime‐target relationship was manipulated along both the identity and the modality dimensions. The prime and the target could refer to either the same or different semantic identities, and could be delivered via either the same or different sensory modalities. By calculating the main effects and interactions of this 2 (identity cue validity: “Identity_Cued” vs. “Identity_Uncued”) × 2 (modality cue validity: “Modality_Cued” vs. “Modality_Uncued”) factorial design, we aimed at dissociating three neural networks involved in creating novel identity‐specific representations independent of sensory modality, in creating modality‐specific representations independent of semantic identity, and in evaluating changes of an object along both the identity and the modality dimensions, respectively. Our results suggested that bilateral lateral occipital cortex was involved in creating a new supramodal semantic representation irrespective of the input modality, left dorsal premotor cortex, and left intraparietal sulcus were involved in creating a new modality‐specific representation irrespective of its semantic identity, and bilateral superior temporal sulcus was involved in creating a representation when the identity and modality properties were both cued or both uncued. In addition, right inferior frontal gyrus showed enhanced neural activity only when both the identity and the modality of the target were new, indicating its functional role in novelty detection. Hum Brain Mapp 35:4002–4015, 2014. © 2014 Wiley Periodicals, Inc.
FROM MAID TO MOTHER: TRANSFORMING FACILITIES, STAFF TRAINING, AND CAREGIVER DIGNITY IN AN INSTITUTIONAL FACILITY FOR YOUNG CHILDREN IN NEPAL
Authors: Wright Amy Conley , Lamsal Dhirendra , Ksetree Mukunda , Sharma Aalok , Jaffe Kenneth
Published: January 2014

This article provides a case study of a project to improve the health, safety, and development of children birth to 6 years old in a large orphanage in Nepal. Two interventions were conducted: improvement of physical infrastructure and training, mentoring, and support for caregiving staff. As a result of these interventions, positive outcomes in terms of children's health and development have been observed, including reduction of communicable diseases and increased social interactions with caregivers. As part of the new trainining initiative, the caregivers began to meet regularly to share their ideas and experiences, and came to realize their vital role in the holistic development of the children in their care. One important change was a greater sense of dignity for the caregivers. The caregivers were formerly called Maids (Aaya), but asked to be called Mothers (Aama). The project also faced challenges, including communication barriers related to organizational structure.
Training staff to implement brief stimulus preference assessments
Authors: Weldy Christina R. , Rapp John T. , Capocasa Kelli
Published: January 2014

We trained 9 behavioral staff members to conduct 2 brief preference assessments using 30‐min video presentations that contained instructions and modeling. After training, we evaluated each staff member's implementation of the assessments in situ. Results indicated that 1 or 2 training sessions for each method were sufficient for teaching each staff member to implement each assessment. We briefly discuss the clinical implications of our findings.
Fabrication of a light‐emitting shape memory polymeric web containing indocyanine green
Authors: Torbati Amir H. , Mather Ryan T. , Reeder Jay E. , Mather Patrick T.
Published: January 2014

Dye‐containing polymers are highly desired for a number of commercially and medically relevant applications, such as sensors, medical devices, and drug delivery. In particular, dyes that emit light in the NIR region of the electromagnetic spectrum are of great interest due to the window of transparency for mammalian soft tissue in this range. While the incorporation of dyes into polymeric hosts by diffusion is a method that has been widely used, this approach is problematic in that it lacks uniformity and control over the incorporation. Here, we sought to develop NIR‐emitting polymeric materials with high fluorescence intensity, addressing the problem of uniformity by incorporating the dye in a polymer host using dissolution in a mutual solvent and subsequent electrospinning into a fibrous web. This web could be prepared as a free‐standing film, a coating or, as we will show, a shrink‐wrap medical device label. The primary findings of this study were that an optimal concentration of dye in the polymer host exists, that the fluorescence intensity for fibrous webs greatly exceed that of comparable cast films, and that the dye‐containing webs feature water‐triggered contraction of use for application to medical devices, such as feeding tubes or catheters. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1236–1243, 2014.
Associations Between Perceived Social Reactions to Trauma‐Related Experiences With PTSD and Depression Among Veterans Seeking PTSD Treatment
Authors: Schumm Jeremiah A. , Koucky Ellen M. , Bartel Alisa
Published: January 2014

The Social Acknowledgment Questionnaire (SAQ; Maercker & Mueller, ) is a measure of trauma survivors’ perceptions of social acknowledgment and disapproval from others, and these factors are shown to be associated with posttraumatic stress disorder (PTSD) among civilian trauma survivors. This study seeks to validate the structure of the SAQ among U.S. military veterans and test the hypothesis that family and general disapproval are associated with PTSD and depression among veterans. Participants were 198 U.S. veterans who experienced military trauma and completed an intake evaluation through a Veterans Affairs PTSD treatment program. Structural equation modeling (SEM) results supported a well‐fitting 3‐factor model for the SAQ that was similar to prior studies in capturing the constructs of social acknowledgment, general disapproval, and family disapproval. SEM results also showed that all 3 of the SAQ factors were associated with veterans’ depression (−.31, .22, and .39, respectively), whereas only general disapproval was related to veterans’ PTSD. This is the first study of which we are aware to investigate the factor structure of the SAQ in a veteran sample and to investigate the relationship between SAQ factors and trauma survivors’ depression. Results build upon prior findings by showing the importance of positive and negative social reactions to veterans’ traumatic experiences.
Genetic dysregulation in recurrent respiratory papillomatosis
Authors: Rodman Regina , Mutasa Simukayi , Dupuis Crystal , Spratt Heidi , Underbrink Michael
Published: January 2014

Objectives/Hypothesis

Recurrent respiratory papillomatosis (RRP) is a devastating disease, caused by infection of the upper aerodigestive tract with human papillomavirus types 6 and 11. There is no cure for RRP, and surgical removal is the mainstay of treatment. The purpose of this project was to compare genes of cell cycle, apoptosis, and inflammatory cytokines in laryngeal papilloma versus normal tissue for a better understanding of the molecular mechanisms of the disease to discover novel therapies.

Study Design

Basic science research study.

Methods

Papilloma tissue was obtained from patients requiring surgical debridement. For comparison, normal mucosa was obtained from the excised uvula of patients undergoing uvulopalatopharyngoplasty. Total RNA was extracted from both groups and then probed using customized reverse transcriptase real time polymerase chain reaction gene arrays.

Results

The custom arrays examine expression of 84 separate genes within the cell cycle, apoptosis, and inflammatory cytokine pathways. Our findings based on 11 papilloma samples run in comparison to normal mucosa shows that the MCL−1 gene of the apoptosis pathway is significantly downregulated. cytokine genes IL1‐A, IL‐8, IL‐18, and IL‐31 are also significantly dysregulated.

Conclusions

Genes of cell cycle and apoptosis are generally upregulated and downregulated, respectively, as expected in papilloma tissue, with MCL‐1 achieving significance when compared to normal tissue. The finding of particular interest is that inflammatory cytokine genes were significantly downregulated, including IL1‐A, IL‐18, and IL‐31. This finding may explain why patients infected with the virus are unable to mediate a T‐cell immune clearance of their disease.

Level of Evidence

NA Laryngoscope, 124:E320–E325, 2014
A flexible blue light sensitive organic photodiode with high properties for the applications in low‐voltage‐control circuit and flexion sensors
Authors: Li Dong , Liu Xiaohui , Dong Guifang , Duan Lian , Zhang Deqiang , Zhao Haoyan , Wang Liduo , Qiu Yong
Published: January 2014

Low‐voltage‐control circuit is one of the most important parts of the modern electrical control system due to the avoidance of operation risk and easy automation. Here, based on a C60: m‐MTDATA bulk heterojunction, a blue‐light‐sensitive organic photodiode (OPD) is explored for the development of flexible low‐voltage‐control circuit. The control of circuit under 2000 V high voltage is achieved. The influences of the organic‐layer thickness, the donor/acceptor volume ratio and the matching of energy levels on the photocurrent are investigated. The maximum light/dark current ratio and current transfer ratio of 1.3 × 104 and 1.3% are achieved, respectively. The highest photoresponse is up to 130 mA/W, markedly higher than some commercial inorganic photodiodes. This device could also be used as flexion and mechanical force sensors with the current density changing under different bending conditions. Therefore, this sort of OPD has a promising application in low‐voltage‐controlled, high‐voltage‐endurable hands for intelligent robots.
Environmentally friendly synthesis of noble metal nanoparticles assisted by biodegradable dextran‐graft‐lactone copolymers
Authors: Saldias Cesar , Leiva Angel , Valderas Johanna , Radic´ Deodato
Published: January 2014

A simple “green synthesis” of noble metal nanoparticles by direct reaction between Dextran‐graft‐lactone copolymers and metal salts without the need to separately add reducing and stabilizing agents was carried out. The effects of the composition, molecular weights of copolymers and solvents on the characteristics of the nanoparticles were considered. The amphiphilic character of the copolymers seems to be an important factor in the results of the synthesis. According to the results, general correlations between experimental parameters of synthesis and characteristics of the obtained nanoparticles were established. Techniques such as, transmission electron microscopy, scanning electron microscopy, UV–visible spectroscopy, Zeta Potential, dynamic light scattering and Fourier transform Infrared Spectroscopy, were used for the characterization of the products. The results indicate the possibility of control of the characteristics of the nanostructured material. Copyright © 2014 John Wiley & Sons, Ltd.
Age is not a prognostic factor in children with Wilms tumor beyond stage I in Africa
Authors: Aronson D.C. , Hadley G.P.
Published: January 2014

Background

Patients under age 4 with stage I favorable histology (FH) Wilms tumor have a reported survival advantage. Among children above 10 years, a poorer prognosis has been associated with a higher prevalence of diffuse anaplasia. Purpose: To determine if, in our practice, patients with Wilms tumors >8 years of age (stage II–V) have a poorer prognosis than those aged <8 years or <4 years.

Procedure

Case‐control study of 19 patients >8 years with Wilms tumor stages II–V who were identified from a cohort of 192 new patients (2002–2012). For each patient two controls were chosen matched for stage and histology, one 0–3 years and one 4–7 years. Neo‐adjuvant chemotherapy was offered to all, combined with intensive supportive care. Postoperative treatment was determined by local stage and histology. OS and EFS at 5 years for the different age groups were compared.

Results

Each age group contained 19 patients, of whom 6 had stage II tumors, 3 stage III, 8 stage IV, and 2 stage V. Histology was intermediate risk (IR) in 17 and high risk (HR) in 2. OS at 5 years was 80.8% and EFS was 79.2% for the whole group. No significant difference in outcome could be shown between age groups. Loss to follow up was 6/57 (11%).

Conclusions

The survival advantage of young age (<4 years) associated with stage I FH could not be demonstrated in higher stages. Age had no significant impact on prognosis although a trend to better outcome was seen in children <4 years. Pediatr Blood Cancer 2014;61:987–989. © 2014 Wiley Periodicals, Inc.
Properties of rice husk‐HDPE composites after exposure to thermo‐treatment
Authors: Wang Weihong , Yang Xiaohui , Bu Fanhua , Sui Shujuan
Published: January 2014

Natural fiber reinforced thermo‐plastic composite, with its often‐excellent properties, is well known as a material for external flooring and landscaping. Thermo‐treatment is considered as a method to improve the mechanical properties of these composites; however, oxidation might occur. In this article, thermo‐treatment is applied to a rice husk reinforced high density polyethylene (RH‐HDPE) composite. Variations in the mechanical properties, color, mass, and chemical constituents of the RH‐HDPE composite after thermo‐treatment were investigated. The results indicated that, with the extension of thermo‐treatment time, the color of the composites darkened; the composites underwent a gradual mass loss; during the early stages of thermo‐treatment the composite's flexural properties increased, and then remained stable after 128 h of treatment. Fourier transform infrared (FTIR) spectroscopy analysis showed wood indices of the RH‐HDPE composite decreased, indicating thermo‐degradation occurred during thermo‐treatment. Wide angle X‐ray diffraction (WAXD) results indicated an increased crystallinity of the RH‐HDPE composite in the first 128 h of thermo‐treatment, and increased crystalline grain size in the first 64 h of thermo‐treatment. Appropriate thermo‐treatment is essential to improve the mechanical properties of RH‐HDPE composites. POLYM. COMPOS., 35:2180–2186, 2014. © 2014 Society of Plastics Engineers
Nonlinear viscoelasticity and stress‐softening behavior of chloroprene rubber reinforced by multiwalled carbon nanotubes
Authors: Feng Chi , Zhang Hongmei , Zhang Yong
Published: January 2014

The viscoelasticity and stress‐softening behavior of chloroprene rubber (CR) filled with multiwalled carbon nanotubes (MWCNT) and carboxylated multiwalled carbon nanotubes (MWCNT‐COOH) were studied using a Rubber Process Analyzer 2000 (RPA2000). In the strain sweep measurements, it is found that CR/MWCNT and CR/MWCNT‐COOH compounds have different behavior on storage modulus (G′). With increasing strain, G′ of CR/MWCNT (100/8) compound decreases at strain less than 2°, while G′ of CR/MWCNT‐COOH (100/8) compound stays at constant, indicating that MWCNT‐COOH has stronger filler–filler network and filler–rubber interactions as compared to MWCNT in CR matrix. CR/MWCNT (MWCNT‐COOH) vulcanizates have higher G′ but lower loss modulus (G″) than the corresponding uncured compounds. Repeated strain sweep scans were carried out to study the stress‐softening behavior of CR compounds. A stress‐softening effect of the filled CR compounds is observed and becomes more pronounced with increasing loading of MWCNT or MWCNT‐COOH. The correlation between the Payne effect and stress‐softening effect of CR/MWCNT (MWCNT‐COOH) vulcanizates is also studied. It is found that the difference of the storage moduli at 0.1° and 10° strain amplitudes and the difference of storage moduli of first and second strain sweeps at 0.1° strain amplitude show a positive linear correlation. POLYM. COMPOS., 35:2194–2202, 2014. © 2014 Society of Plastics Engineers
An Easy, Convenient Cell and Tissue Extraction Protocol for Nuclear Magnetic Resonance Metabolomics
Authors: Matheus Nicolas , Hansen Sylvain , Rozet Eric , Peixoto Paul , Maquoi Erik , Lambert Vincent , Noël Agnès , Frédérich Michel , Mottet Denis , de Tullio Pascal
Published: January 2014

Introduction

As a complement to the classic metabolomics biofluid studies, the visualisation of the metabolites contained in cells or tissues could be a very powerful tool to understand how the local metabolism and biochemical pathways could be affected by external or internal stimuli or pathologies. Therefore, extraction and/or lysis is necessary to obtain samples adapted for use with the current analytical tools (liquid NMR and MS). These extraction or lysis work‐ups are often the most labour‐intensive and rate‐limiting steps in metabolomics, as they require accuracy and repeatability as well as robustness. Many of the procedures described in the literature appear to be very time‐consuming and not easily amenable to automation.

Objective

To find a fast, simplified procedure that allows release of the metabolites from cells and tissues in a way that is compatible with NMR analysis.

Methods

We assessed the use of sonication to disrupt cell membranes or tissue structures. Both a vibrating probe and an automated bath sonicator were explored.

Results

The application of sonication as the disruption procedure led to reproducible NMR spectral data compatible with metabolomics studies. This method requires only a small biological tissue or cell sample, and a rapid, reduced work‐up was applied before analysis. The spectral patterns obtained are comparable with previous, well‐described extraction protocols.

Conclusion

The rapidity and the simplicity of this approach could represent a suitable alternative to the other protocols. Additionally, this approach could be favourable for high‐ throughput applications in intracellular and intratissular metabolite measurements. Copyright © 2014 John Wiley & Sons, Ltd.
Study on thermal stability and flame retardancy of polymer/layered silicate nanocomposites based on POE and POE‐g‐MAH
Authors: Qin Shuhao , Li Qinfeng , He Min , Shao Huiju , Yu Jie , Guo Jianbing , Zhang Kai , Yan Wei
Published: January 2014

Ethylene‐octene elastomer (POE)/organo‐montmorillonite (OMT) and maleic anhydride‐grafted POE (POE‐g‐MAH)/OMT composites were prepared through melt mixing and influence of clay dispersion on thermal, dynamic mechanical, and flammability properties were investigated. The results showed that OMT forms intercalated/exfoliated structures in POE‐g‐MAH/OMT and agglomerated structure in POE/OMT microcomposites, resulting in more significant improvements of storage modulus and glass transition temperature in the POE‐g‐MAH/OMT rather than the POE/OMT composites. The POE‐g‐MAH/OMT nanocomposites have better thermal stability and significantly reduced flammability than the POE/OMT microcomposites, which was discussed on the basis of cone colorimeter test of the composites and energy dispersive X‐ray spectrum analysis of the combustion chars. POLYM. ENG. SCI., 54:2911–2917, 2014. © 2014 Society of Plastics Engineers
Surface modification of a calcium fluoride filler and the effect on the nonisothermal crystallization behavior of poly(ethylene terephthalate)
Authors: Sánchez‐Leija Regina Janet , Riba‐Moliner Marta , Cayuela‐Marín Diana , Domínguez‐Espinós Octavio , Sánchez‐Loredo María Guadalupe
Published: January 2014

Two different types of calcium fluoride particles (∼325 nm), one of them surface modified using a long‐chain organophosphorous reagent, were incorporated into a poly(ethylene terephthalate) (PET) matrix. The CaF2 particles were synthesized by a simple chemical precipitation method. To modify the particles surface, a heat treatment using Cyanex® 921 [tri‐n‐octylphosphine oxide (TOPO)] dissolved in isopropanol, was carried out. Therefore, unlike the as‐synthesized particles, the modified particles contained an amount of TOPO. The composite materials were prepared by melt‐blending PET and particles at different filler loadings. The influence of the particles surface modification on the nonisothermal crystallization behavior of PET was investigated by using differential scanning calorimetry and field emission scanning electron microscopy. The Jeziorny‐modified Avrami equation was applied to describe the crystallization kinetics and several parameters were analyzed (half‐crystallization time, Avrami exponent, and rate constant). According to the results, the fluorite particles act as nucleating agents, accelerating the PET crystallization rate. However, the effect on the polymer crystallization rate was more noticeable with the addition of the nonmodified particles where the surface might play an important role for epitaxial crystallization, while the addition of the particles, with an organic coating layer on the surface, resulted in a crystallization behavior more similar to the observed for neat PET. POLYM. ENG. SCI., 54:2938–2946, 2014. © 2014 Society of Plastics Engineers
Quantitative phosphoproteomic analysis of RIP3‐dependent protein phosphorylation in the course of TNF‐induced necroptosis
Authors: Zhong Chuan‐Qi , Li Yuanyue , Yang Daowei , Zhang Na , Xu Xiaozheng , Wu Yaying , Chen Jinan , Han Jiahuai
Published: January 2014

Tumor necrosis factor (TNF) induced cell death in murine fibrosarcoma L929 cells is a model system in studying programed necrosis (also known as necroptosis). Receptor interacting protein 3 (RIP3), a serine–threonine kinase, is known to play an essential role in TNF‐induced necroptosis; however, the phosphorylation events initiated by RIP3 activation in necroptotic process is still largely unknown. Here, we performed a quantitative MS based analysis to compare TNF‐induced changes in the global phosphoproteome of wild‐type (RIP3+/+) and RIP3‐knockdown L929 cells at different time points after TNF treatment. A total of 8058 phosphopeptides spanning 6892 phosphorylation sites in 2762 proteins were identified in the three experiments, in which cells were treated with TNF for 0.5, 2, and 4 h. By comparing the phosphorylation sites in wild‐type and RIP3‐knockdown L929 cells, 174, 167, and 177 distinct phosphorylation sites were revealed to be dependent on RIP3 at the 0.5, 2, and 4 h time points after TNF treatment, respectively. Notably, most of them were not detected in a previous phosphoproteomic analysis of RIP3‐dependent phosphorylation in lipopolysaccharide‐stimulated peritoneal macrophages and TNF‐treated murine embryonic fibroblasts (MEFs), suggesting that the data presented in this report are highly relevant to the study of TNF‐induced necroptosis of L929 cells.
Addressing enablers in layers of protection analysis
Authors: Baybutt Paul
Published: January 2014

Layers of protection analysis (LOPA) is used to evaluate the risk of individual hazard scenarios by combining initiating event frequencies with failure probabilities of protection layers. Some practitioners include events and conditions that enable the occurrence of hazard scenarios in the analysis, such as conditional modifiers, but sometimes they are excluded to ensure conservative results. However, these events and conditions, and other factors that enable scenarios, are often key parts of hazard scenarios and their exclusion from the analysis can result in overly conservative results. This article broadens the definition of enabling events and conditions to include other factors that can have a significant impact on the risk of hazard scenarios. Such other factors include management systems to account for inadequacies in, and failure to follow, policies, procedures, and work instructions; at‐risk factors to account for the time period in which a process is at risk; incident outcomes to represent different possible consequences for the same initiating event; and release conditions to account for different release conditions or circumstances. Their inclusion in LOPA studies is described with examples. The determination of adjustment factors to account for their effect on scenario risk is also demonstrated. © 2014 American Institute of Chemical Engineers Process Saf Prog 33: 221–226, 2014
Charge trapping and physical parameters of Er3+ doped light‐emitting field‐effect transistors
Authors: Ramírez J. M. , Berencén Y. , Garrido B.
Published: January 2014

The electrical properties of light‐emitting field‐effect transistors with Er3+ doped gate oxides formed either by a Si‐rich oxide or by a SiO2 are studied. Measured output and transfer characteristics in combination with C–V curves allowed for the main device parameters determination (flat‐band voltage, Debye length, or low‐field mobility). Decreased threshold voltage, interface charge trapping and low‐field mobility enhancement in devices containing Si‐rich oxides respect to those with Er3+ doped SiO2 gate are found. In addition, the implantation of Er3+ ions in the gate oxide produced significant low‐field mobility reduction in the transistor inversion layer.

Typical polarization scheme and device cross section of a light‐emitting field‐effect transistor (left). Erbium electroluminescence spectrum collected from the top of the polysilicon gate (right).
Calculation of the capacitance–voltage characteristics of a metal–insulator‐correlated oxide capacitor with dynamical mean‐field theory
Authors: Bakalov Petar , Ydens Bart , Locquet Jean‐Pierre
Published: January 2014

Accurate modeling is essential for the development of electronic devices. While there are many theoretical approaches based on band theory and the effective mass approximation which are capable of simulating the operation of conventional semiconductor devices, these methods cannot be applied to devices based on strongly correlated electron materials because band theory fails to capture strongly correlated physics. Here the electric potential across a metal–insulator‐correlated oxide structure with a strongly correlated oxide layer is computed by numerical integration of the Poisson equation as the oxide approaches a metal‐to‐insulator transition (MIT). DMFT is used to calculate the charge density as a function of potential in the strongly correlated oxide layer. C–V curves are produced on the basis of the charge density data.
Surface preparation of non‐polar single‐crystalline AlN substrates
Authors: Bryan Isaac , Akouala Christer‐Rajiv , Tweedie James , Bryan Zachary , Rice Anthony , Kirste Ronny , Collazo Ramón , Sitar Zlatko
Published: January 2014

A surface preparation technique has been developed for non‐polar m‐plane aluminum nitride (AlN) single crystalline substrates. Chemical surface treatments were conducted on chemomechanically polished m‐plane oriented AlN substrate surfaces. X‐ray photoelectron spectroscopy was used to characterize the surface chemistry after each processing step. A layer of mixed aluminum oxide‐hydroxide was identified on ambient air‐exposed surfaces. Analysis of the oxygen core level spectra showed oxygen in three bonding states, identified by the binding energies and relative separation of the fitted peaks as O2−, OH− and H2O. Molar ratios of different components showed the oxide to be dominantly bonded in the OH− state. Wet etching reduced the amount of surface oxides. Ammonia annealing at 1100 °C converted the aluminum oxide‐hydroxide layer to AlN. Although the overall amount of the oxide on the surface was reduced by surface treatments, the nature of the oxide remained predominantly of the OH−character. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Diversifying instruction and shifting authority: A cultural historical activity theory (CHAT) analysis of classroom participant structures
Authors: Patchen Terri , Smithenry Dennis W.
Published: January 2014

Recent calls asking science teachers to increase student authority by diversifying instruction appear stalled by a lack of empirical evidence supporting the actual implementation of any such shifts. To better support the practical integration of more student‐directed inquiry into the science classroom, we consider one teacher's day‐to‐day praxis within the context of a yearlong chemistry curriculum. Using cultural historical activity theory (CHAT) we analyze how the interplay of key classroom elements (i.e., the classroom community, subjects, division of labor, mediating artifacts, rules, objects, and outcomes) varies within and across three distinct participant structures, and thus shapes what students experience as science. We construct CHAT activity models of each of the participant structures in order to examine how the teacher's differentiated use of traditional classroom mechanisms (e.g., whole class discussions and critique) scaffolds students' developing ability to direct their own inquiries. Our study demonstrates how a teacher can link elements within and between a diverse set of participant structures in ways that systematically create real opportunities for student‐directed inquiry and collaboration while assuring students learn to act with disciplinary authority. © 2014 Wiley Periodicals, Inc. J Res Sci Teach 51: 606–634, 2014
A measurement‐based study of handover improvement through range expansion and interference coordination
Authors: Kuang Quan , Belschner Jakob , Bleicher Zarah , Droste Heinz , Speidel Joachim
Published: January 2014

Although the range expansion and inter‐cell interference coordination (ICIC) have been shown to successfully enhance the capacity and load balancing in the Heterogeneous Network, their impacts on the handover (HO) performance are not fully understood in existing studies. In this paper, a novel measurement‐based approach is adopted to investigate these issues, where the real measured data of the reference signal received power in a macro–pico co‐channel deployment are collected. Then the mobility performance in terms of the HO failure rate and ping‐pong rate is simulated with various ICIC schemes in the same reality environment. This has been made possible by modeling the possible HO failure events based on evaluating the downlink received signal‐to‐interference‐plus‐noise ratio from reference signal received power. The simulation results indicate that range expansion together with ICIC can have positive or negative influences on macro‐to‐pico, pico‐to‐macro, pico‐to‐pico and macro‐to‐macro HOs in the Heterogeneous Network. The existing static ICIC or mobility‐based ICIC cannot handle the intra‐layer (pico‐to‐pico and macro‐to‐macro) interference, thus limiting their abilities to improve the mobility performance. Motivated by this, a dynamic‐ICIC‐aided HO procedure is proposed. The proposed HO enhancement method is more flexible and effective in mitigating both the inter‐layer and intra‐layer interference, outperforming the existing methods significantly. Copyright © 2014 John Wiley & Sons, Ltd.
Ln9Al5Sn10: Aluminium Stannides of the Divalent Rare Earth Elements Yb and Eu. Synthesis, Crystal Structure, and Chemical Bonding
Authors: Lang Britta , Röhr Caroline
Published: January 2014

The isotypic aluminium stannides Ln9Al5Sn10 (Ln = Yb, Eu) are the first ternary compounds in the systems Yb‐Al‐Sn and Eu‐Al‐Sn. They were synthesized in the course of systematic experimental work on the phase stability along the sections LnAl2 – LnSn2 from the elements at maximum temperatures of 1170 K. Their crystal structures were determined using single‐crystal X‐ray diffraction [both monoclinic, space group C2/m, a = 2145.2(5)/2214.99(8), b = 1189.15(14)/1236.67(4), c = 1003.9(2)/1027.57(4) pm, β = 103.22(2)/103.300(3)°, Z = 2, R1 = 0.0492/0.0515 for Ln = Yb/Eu]. The two phases are isotypic to the respective calcium/strontium Al stannides. Their crystal structure can be best described as a complex three‐dimensional network, consisting of three different building units (motifs I, II, and III), which are connected by two‐bonded tin atoms (motif 0). The first motif is a planar zigzag chain of tin like in the CrB‐type structure of e.g. EuSn. Ladders of four‐bonded Al/Sn atoms (motif II) are also present in SrAl2 (KHg2 structure type). The trigonal‐bipyramidal units [Al3Sn2] of motif III, which can alternatively be described as three AlSn4 tetrahedra sharing one common edge, are also known from binary barium aluminides like Ba7Al10. In the Yb compound, this motif III is to a small extent of 17 % statistically substituted by an alternative but related motif IIIB, which consists of only two edge‐sharing AlSn4 tetrahedra. Despite the complex structure and some statistically occupied Al/Sn positions, the chemical bonding in the title compounds can be rationalized using the Zintl concept: Both the interpretation as aluminide/stannides and stannido‐aluminates results in only a minuscule difference between the formal charge of the Al/Sn polyanion and the charge sum of the divalent rare earth cations. FP‐LAPW bandstructure calculations of an ordered subgroup model of the europium compound confirm this interpretation in exhibiting a pronounced minimum of the tDOS slightly below the Fermi level.
Current Knowledge in Soybean Composition
Authors: Medic Jelena , Atkinson Christine , Hurburgh Charles R.
Published: January 2014

The soybean [Glycine max (L.) Merr.] is grown worldwide for its high protein and oil contents. Characterization of soybean seed components lends itself to understanding how soybean production can meet the needs of a growing world population. For this article, literature was reviewed and condensed to create a well‐rounded picture of the current understanding of structural, functional, and nutritional properties of soybean components. Natural variation in soybean protein, lipid, and carbohydrate components, as well as the minor constituents phytic acid and isoflavones, are mentioned. Environment‐ or genetic‐induced shifts in natural variation are described with respect to nutrition and functional improvements in soybean.
Effects of palmitoylation on the diffusional movement of BKCa channels in live cells
Authors: Kim Sulgi , Lee Byoung-Cheol , Lee A-Ram , Won Sehoon , Park Chul-Seung
Published: January 2014

BKCa channels are palmitoylated at a cluster of cysteine residues within the cytosolic linker connecting the 1st and 2nd transmembrane domains, and this lipid modification affects their surface expression. To verify the effects of palmitoylation on the diffusional dynamics of BKCa channels, we investigated their lateral movement. Compared to wild‐type channels, the movement of mutant palmitoylation‐deficient channels was much less confined and close to random. The diffusion of the mutant channel was also much faster than that of the wild type. Thus, the lateral movement of BKCa channels is greatly influenced by palmitoylation.