bluuebunny/crossref_metadata_2025 huggingface dataset:
Organizational Attitudes as Precursors to Training Performance
Authors: Kim Sungjun , Hahn Huh‐Jung , Lee Jinkyu
Published: August 2015

In most prior research on training and development, employees’ attitudes toward their organization have been viewed as consequences of training interventions rather than as antecedents. This study asserts that affective organizational commitment and organizational identification are performance predictors of training designed to directly address the collective interests of the organization. Additionally, we expected that organizational identification has a stronger positive effect on training performance than does organizational commitment. To test these hypotheses, the independent variables were measured in 149 trainees prior to the beginning of the training program. Observers’ ratings of behavioral performance were evaluated as the training outcome using an assessment center method. The analysis showed that organizational identification significantly predicts training performance, whereas organizational commitment does not.
A Study On Assessment Financing Of Irrigation Schemes
Authors: Koç Cengİz , Bayazit Yildirim
Published: August 2015

In this study, it is aimed to present the relative activities and efficiencies of management operation and maintenance (MOM) services achieved by irrigation associations in Büyük Menderes Basin, Turkey. From the 16 irrigation associations operating and taking over the irrigation schemes which are under the operation and constructed by DSI (State Hydraulic Works) in the province of Aydın, the performance and efficiencies of eight irrigation associations having an area bigger than 1000 ha were evaluated. Efficiencies and performance related to MOM activities of irrigation associations were calculated and compared with methods of dissimilarity factor value. Furthermore, the construction costs per unit area utilizing the scheme type were calculated for the irrigation schemes researched. Financial self‐sufficiency of irrigation associations in the basin was found to range from 1.64 to 0.79. Fee collection performance for Akçay Right Bank, Akçay Left Bank and Nazilli Left Bank irrigation associations was low, while it was satisfactory for Soke, Karpuzlu Yaylakavak, Aydin, Çine Topçam and Nazilli Right Bank irrigation associations. Financial stabilization and sustainability performance class for the eight irrigation schemes actualized between 'very poor' and ‘average’. The cost of construction calculated per unit area researched ranged from US$5440 to 8500 ha‾1. Copyright © 2015 John Wiley & Sons, Ltd.
Flagellar membrane proteins in kinetoplastid parasites
Authors: Landfear Scott M. , Tran Khoa D. , Sanchez Marco A.
Published: August 2015

All kinetoplastid parasites, including protozoa such as Leishmania species, Trypanosoma brucei, and Trypanosoma cruzi that cause devastating diseases in humans and animals, are flagellated throughout their life cycles. Although flagella were originally thought of primarily as motility organelles, flagellar functions in other critical processes, especially in sensing and signal transduction, have become more fully appreciated in the recent past. The flagellar membrane is a highly specialized subdomain of the surface membrane, and flagellar membrane proteins are likely to be critical components for all the biologically important roles of flagella. In this review, we summarize recent discoveries relevant to flagellar membrane proteins in these parasites, including the identification of such proteins, investigation of their biological functions, and mechanisms of selective trafficking to the flagellar membrane. Prospects for future investigations and current unsolved problems are highlighted. © 2015 IUBMB Life, 67(9):668–676, 2015
The toxic effects of indoor atmospheric fine particulate matter collected from allergic and non‐allergic families in Wuhan on mouse peritoneal macrophages
Authors: Yan Biao , Li Jinquan , Guo Junhui , Ma Ping , Wu Zhuo , Ling ZhenHao , Guo Hai , Hiroshi Yoshino , Yanagi U. , Yang Xu , Zhu Shengwei , Chen Mingqing
Published: August 2015

Recent studies have shown that fine particulate matter (PM2.5) is associated with multiple adverse health outcomes and PM2.5‐induced oxidative stress is now commonly known as a proposed mechanism of PM2.5‐mediated toxicity. However, the association between allergic symptoms in children and exposure to PM2.5 has not been fully elucidated, particularly the role of PM2.5 on the indoor environment involved in allergy or non‐allergy is unknown. The aim of the present study was to explore whether indoor PM2.5 from the homes of children with allergic symptoms had more increased risks of allergy than that of healthy ones and then compare the toxicity and inflammatory response of them. In this study, indoor PM2.5 was collected from the homes of schoolchildren with allergic symptoms and those of healthy ones respectively, and components of PM2.5 were analyzed. PM2.5‐mediated oxidative damage and inflammatory response were further evaluated in mouse peritoneal macrophages based on its effects on the levels of reactive oxygen species accumulation, lipid peroxidation, DNA damage or cytokine production. It seems that oxidative stress may contribute to PM2.5‐induced toxicity, and PM2.5 from the allergic indoor environment produced more serious toxic effects and an inflammatory response on mouse peritoneal macrophages than that from a non‐allergic indoor environment. Copyright © 2015 John Wiley & Sons, Ltd.
Human ketosteroid receptors interact with hazardous phthalate plasticizers and their metabolites: an in silico study
Authors: Sarath Josh M. K. , Pradeep S. , Vijayalekshmy Amma K. S. , Sudha Devi R. , Balachandran S. , Sreejith M. N. , Benjamin Sailas
Published: August 2015

Phthalic acid esters or phthalates are ubiquitous environmental pollutants known for their adverse health effects in test animals and, of late, in humans. Thus, in this molecular docking study – using Glide (Schrödinger) – the molecular interactions of 31 ligands, including 12 diphthalates, their monophthalates and phthalic acid with selected human ketosteroid receptors, i.e., androgen (hAR), progesterone (hPR) and glucocorticoid (hGR) receptors were explored and their binding affinities were compared with that of corresponding natural steroids and a known endocrine disrupting xenobiotic, bisphenol A (BPA). Mostly, diphthalates and monophthalates showed the potential for antisteroidal activity by interacting with hAR, hPR and hGR. Of them, diphenyl phthalate showed the highest G score (–7.70 kcal mol–1) with hAR, and the crucial amino acid (aa) residues in the ligand binding domain (LBD) of this receptor involved in the molecular interactions were Phe 764, Leu 704, Asn 705 and Thr 877. The mono‐iso‐decyl phthalate showed the highest G score (–8.36) with the hPR, and the crucial aa residues in the LBD interactions were Arg 766 Gln 725 and Phe 778. The mono‐iso‐decyl phthalate also showed more affinity (–8.44) towards hGR than the natural ligand, and the aa residues in the LBD interactions were Gln 570 and Met 604. In addition to these, some other phthalates established comparable interactions with certain aa residues located in the LBD of these receptors, which resulted in higher G scores. Contrastingly, BPA and some natural ligands tested in this study showed lower G scores with these receptors than certain phthalates reported herein, i.e., certain phthalates are more toxic than the proven toxic BPA. Copyright © 2015 John Wiley & Sons, Ltd.
Improving the permeability of lyophilized collagen–hydroxyapatite scaffolds for cell‐based bone regeneration with a gelatin porogen
Authors: Villa Max M. , Wang Liping , Huang Jianping , Rowe David W. , Wei Mei
Published: August 2015

Bone tissue engineering using biomaterial scaffolds and culture‐expanded osteoprogenitor cells has been demonstrated in several studies; however, it is not yet a clinical reality. One challenge is the optimal design of scaffolds for cell delivery and the identification of scaffold parameters that can delineate success and failure in vivo. Motivated by a previous experiment in which a batch of lyophilized collagen‐hydroxyapatite (HA) scaffolds displayed modest bone formation in vivo, despite having large pores and high porosity, we began to investigate the effect of scaffold permeability on bone formation. Herein, we fabricated scaffolds with a permeability of 2.17 ± 1.63 × 10−9 m4/(N s) and fourfold higher using a sacrificial gelatin porogen. Scaffolds were seeded with mouse bone marrow stromal cells carrying a fluorescent reporter for osteoblast differentiation and implanted into critical‐size calvarial defects in immunodeficient mice. The porogen scaffold group containing a 1:1 ratio of solids to beads was significantly more radiopaque than the scaffold group without the bead porogen 3 weeks after implantation. Quantitative histomorphometry uncovered the same trend between the 1:1 group and scaffolds without porogen found in the radiographic data; however, this was not statistically significant here. Taken together, the X‐ray and histology suggest that the 1:1 ratio of porogen to scaffold solids, resulting in a fourfold increase in permeability, may enhance bone formation when compared to scaffolds without porogen. Scaffold permeability can be a useful quality control measure before implantation and this practice should improve the consistency and efficacy of cell‐based bone tissue engineering. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1580–1590, 2016.
Genotype GG of rs895819 Functional Polymorphism Within miR‐27a Might Increase Genetic Susceptibility to Colorectal Cancer in Han Chinese Population
Authors: Jiang Yu , Lin Dong‐Hong , Xu Jian‐Ping , Chen Wen‐XU , Zheng Shu‐Jian , Song Lin
Published: August 2015

Background

MicroRNA‐27a (miR‐27a) is supposed to be an oncogene in various types of cancers, and genetic variation of miR‐27a might result in aberrant expression and abnormal second structure of mature‐miR‐27a, contributing to elevated genetic risk and poor prognosis for colorectal cancer (CRC).

Methods

In order to explore the possible association between rs895819 within miR‐27a and CRC in Han Chinese population, we investigated the genotype distributions of rs895819 in 508 CRC cases and 562 healthy check‐up controls using TaqMan genotype discrimination system, and analyzed the possible association between them. Odds ratio (OR) and 95% confidential interval (95% CI) were used to assess the strength between allele and genotype of the locus and risk of CRC.

Results

In our study, we found that genotype GG of rs895819 was significantly associated with an increased risk for CRC (17.1% vs. 11.6%, adjusted OR = 1.546, 95% CI = 1.070–2.236), and allele A carrier (AA/AG) was significantly associated with a decreased risk for CRC (82.9% vs. 89.4%, adjusted OR = 0.63, 95% CI = 0.446–0.893). In addition, a significant association was observed between genotype GG and larger tumor size (>5 cm; P < 0.001), and allele G was significantly associated with higher pathological stage (TNM‐III) (P = 0.008).

Conclusion

These results indicated that miR‐27a might be involved in the development and progression of CRC, genotype GG within rs895819 might be a genetic susceptible factor for CRC. Further multicentral, large sample size, and well‐designed epidemiological study as well as functional study are warrant to verify our findings.
Automated Cerebrospinal Fluid Cell Counts Using the New Body Fluid Mode of Sysmex UF‐1000i
Authors: Buoro Sabrina , Apassiti Esposito Sara , Alessio MariaGrazia , Crippa Alberto , Ottomano Cosimo , Lippi Giuseppe
Published: August 2015

Background

We evaluated the new body fluid module on Sysmex UF1000‐i (UF1000i‐BF) for analysis of white blood cell (WBC) and red blood cell (RBC) in cerebrospinal fluid (CSF).

Methods

WBC and RBC counting were compared between UF1000i‐BF and Fuchs–Rosenthal counting chamber in 67 CSF samples. This study also included the evaluation of between‐day precision, limit of blank (LoB), limit of detection (LoD), functional sensitivity (limit of quantitation, LoQ), carryover and linearity. Diagnostic agreement for differentiation between normal and increased WBC counts (≥5.0 × 106/L) was also assessed.

Results

The agreement between UF1000i‐BF and manual WBC counts was otpiaml in all CSF samples (r = 0.99; y = 1.05x + 0.09). A modest overestimation was noticed in samples with WBC < 30 × 106/L (r = 0.95; y = 1.21x − 0.15). A good agreement was observed for RBC counts (r = 0.98; y = 1.15x + 0.55), particularly in samples with RBC ≥ 18 × 106/L (r = 0.98; y = 1.01x + 8.90). Between‐day precision was good, with coefficient of variations (CVs) lower than 7.2% for both WBC and RBC. The LoBs were 0.1 × 106 WBC/L and 1.2 × 106 RBC/L, the LoDs were 0.7 × 106 WBC/L and 5.5 × 106 RBC/L, the LoQs were 2.4 × 106 WBC/L and 18.0 × 106 RBC/L, respectively. Linearity was excellent (r = 1.00 for both WBC and RBC). Carryover was negligible. Excellent diagnostic agreement was obtained at 4.5 × 106 WBC/L cut‐off (sensitivity, 100%; specificity, 97.4%).

Conclusion

The UF1000i‐BF provides rapid and accurate WBC and RBC counts in clinically relevant values of CSF cells. The use of UF1000i‐BF may hence allow to replace routine optical counting, except for samples displaying abnormal WBC counts or abnormal scattergram distribution, for which differential cell counts may still be required.
Hyperspectral interferometry: Sizing microscale surface features in the pine bark beetle
Authors: Beach James M. , Uertz James L. , Eckhardt Lori G.
Published: August 2015

A new method of interferometry employing a Fabry–Perot etalon model was used to locate and size microscale features on the surface of the pine bark beetle. Oscillations in the reflected light spectrum, caused by self‐interference of light reflecting from surfaces of foreleg setae and spores on the elytrum, were recorded using white light hyperspectral microscopy. By making the assumption that pairs of reflecting surfaces produce an etalon effect, the distance between surfaces could be determined from the oscillation frequency. Low frequencies of less than 0.08 nm−1 were observed in the spectrum below 700 nm while higher frequencies generally occupied wavelengths from 600 to 850 nm. In many cases, two frequencies appeared separately or in combination across the spectrum. The etalon model gave a mean spore size of 3.04 ± 1.27 μm and a seta diameter of 5.44 ± 2.88 μm. The tapering near the setae tip was detected as a lowering of frequency. Spatial fringes were observed together with spectral oscillations from surfaces on the exoskeleton at higher magnification. These signals were consistent with embedded multi‐layer reflecting surfaces. Possible applications for hyperspectral interferometry include medical imaging, detection of spore loads in insects and other fungal carriers, wafer surface and subsurface inspection, nanoscale materials, biological surface analysis, and spectroscopy calibration. This is, to our knowledge, the first report of oscillations directly observed by microscopy in the reflected light spectra from Coleoptera, and the first demonstration of broadband hyperspectral interferometry using microscopy that does not employ an internal interferometer. Microsc. Res. Tech. 78:873–885, 2015. © 2015 Wiley Periodicals, Inc.
In situ synthesis and hydrothermal crystallization of nanoanatase TiO2–SiO2 coating on aramid fabric (HTiSiAF) for UV protection
Authors: Deng Hui , Zhang Hongda
Published: August 2015

TiO2–SiO2 thin film was prepared by sol‐gel method and coated on the aramid fabric to prepare functional textiles. The aramid fabric was dipped and withdrawn in TiO2–SiO2 gel and hydrothermal crystallization at 80°C, then its UV protection functionality was evaluated. The crystalline phase and the surface morphology of TiO2–SiO2 thin film were characterized using SEM, XRD, and AFM respectively. SEM showed hydrothermal crystallization led to a homogeneous dispersion of anatase nonocrystal in TiO2–SiO2 film, and XRD suggested the mean particle size of the formed anatase TiO2 was less than 30 nm. AFM indicated that hydrothermal treatment enhanced the crystallization of TiO2. UV protection analysis suggested that the hydrothermally treated coated textile had a better screening property in comparison with TiO2–SiO2 gel and native aramid fabric. Microsc. Res. Tech. 78:918–925, 2015. © 2015 Wiley Periodicals, Inc.
Sub ablative Er: YAG laser irradiation on surface roughness of eroded dental enamel
Authors: Curylofo‐Zotti Fabiana Almeida , Lepri Taísa Penazzo , Colucci Vivian , Turssi Cecília Pedroso , Corona Silmara Aparecida Milori
Published: August 2015

Objective

This study evaluated the effects of Er:YAG laser irradiation applied at varying pulse repetition rate on the surface roughness of eroded enamel.

Methods

Bovine enamel slabs (n = 10) were embedded in polyester resin, ground, and polished. To erosive challenges, specimens were immersed two times per day in 20mL of concentrated orange juice (pH = 3.84) under agitation, during a two‐day period. Specimens were randomly assigned to irradiation with the Er:YAG laser (focused mode, pulse energy of 60 mJ and energy density of 3.79 J/cm2) operating at 1, 2, 3, or 4 Hz. The control group was left nonirradiated. Surface roughness measurements were recorded post erosion‐like formation and further erosive episodes by a profilometer and observed through atomic force microscopy (AFM).

Results

Analysis of variance revealed that the control group showed the lowest surface roughness, while laser‐irradiated substrates did not differ from each other following post erosion‐like lesion formation. According to analysis of covariance, at further erosive episodes, the control group demonstrated lower surface roughness (P > 0.05), than any of the irradiated groups (P < 0.05).

Conclusions

The pulse repetition rate of the Er:YAG laser did not affect roughness of dental enamel eroded. The AFM images showed that the specimens irradiated by the Er:YAG laser at 1 Hz presented a less rough surface than those irradiated at 2, 3, and 4 Hz. Microsc. Res. Tech. 78:989–993, 2015. © 2015 Wiley Periodicals, Inc.
Classification and assessment of power system static security using decision tree and random forest classifiers
Authors: Sekhar Pudi , Mohanty Sanjeeb
Published: August 2015

The power system static security classification and assessment is essential in order to identify the post‐contingency problems and take corrective measures and to protect the system from blackout. In this paper, application of two data mining classifiers have been proposed for the security classification and assessment of a multiclass security problem. To design the security problem, contingency analysis is carried out under N‐1 line outage, and static severity index (SSI) is computed, which is a function of the line overload and the voltage deviation using Newton–Raphson load flow method, considering the variable load and generating conditions. Corresponding to the computed values of SSI, the voltage, phase angle, Mega Volt Ampere line flow and so on, a 1 × 7 pattern vector is generated. The generated pattern vectors are used to design a multiclass security problem. The designed security pattern vectors are given as inputs to the decision tree (DT) and random forest (RF) model in order to classify the security status of the power system. The proposed classifiers are investigated on an IEEE 30‐bus test system. The classification accuracy of the DT and the RF are compared with state‐of‐the‐art classifier models, namely, multilayer perceptron (MLP), radial basis function (RBF), and support vector machine (SVM).The simulation results clearly indicate that the proposed DT and RF classifiers are more efficient, reliable, and out performs MLP, RBF, and SVM classifiers for the assessment of the security status of the power system. Hence, DT and RF classifiers are found to be suitable for online implementation. Copyright © 2015 John Wiley & Sons, Ltd.
Retracted: Bacteria diversity overview and endoglucanase assessment from Himalayan Tapovan geothermal spring
Authors: Sahoo Jitendra Kumar , Navani Naveen Kumar , Pathania Ranjana
Published: August 2015

The above article from the Journal of Basic Microbiology, published online on 25 August 2015 in Wiley Online Library as Early View (http://onlinelibrary.wiley.com/doi/10.1002/jobm.201500135/pdf), has been retracted by agreement between Naveen Kumar Navani and Ranjana Pathania, the Editor‐in‐Chief and Wiley‐VCH GmbH & Co. KGaA. The retraction has been agreed because the article has been submitted and approved for publication by Jitendra Kumar Sahoo without consent in any form by the named co‐authors Naveen Kumar Navani and Ranjana Pathania.
Mid‐MIS3 climate inferred from reconstructing the Dalijia Shan ice cap, north‐eastern Tibetan Plateau
Authors: WANG JIE , CUI HANG , HARBOR JONATHAN M. , ZHENG LIMIN , YAO PAN
Published: August 2015

The local last glacial maximum (LGML) on Dalijia Shan occurred during mid‐marine isotope stage 3 (MIS3), which is consistent with some Tibetan Plateau records, but asynchronous with the MIS2 global Last Glacial Maximum (LGMG). Paleoclimatic reconstructions are key to advancing understanding such spatial and temporal patterns of paleoglaciation. Using multiple methods we reconstructed mid‐MIS3 equilibrium‐line altitude (ELA) on Dalijia Shan and inferred temperature depressions. Geomorphic ELA reconstructions combined with empirical data on current ELA temperature and precipitation yield a mid‐MIS3 ELA of 4000 ± 78 m a.s.l. (618–851 m lower than current, and a temperature depression of 3.3–6.8 °C). Independent glacial modeling using the degree‐day approach suggests a mid‐MIS3 ELA between 3971 and 4024 m a.s.l. and a temperature depression of 4.2–5.6 °C. The consistency of these results indicate that mid‐MIS3 temperature depressions in the Dalijia Shan region were 3.3–6.8 °C, which is less than the LGMG temperature depression inferred from regional climatic proxy data. Combined with other proxy data, this suggests that the LGML glacial advance in Dalijia Shan resulted from lower temperatures and slightly reduced precipitation compared with present, whereas the LGMG advance was more restricted because much colder conditions were combined with much lower precipitation.
Bistable nano‐structured photoalignment surface by nanoimprint lithography
Authors: Lee Chung‐Yung , Tseng Man‐Chun , Ho Jacob Yeuk‐Lung , Chigrinov Vladimir G. , Kwok Hoi‐Sing
Published: August 2015

A novel nano‐structured photoalignment surface is proposed and demonstrated. Such alignment surface has bistable azimuthal alignment directions for the liquid crystal molecules. The new alignment surface has a structure of stacking a photo‐polymerizable photoalignment polymer on top of a nano‐sized groove surface. The photoalignment polymer and groove surface have different azimuthal alignment directions but the same azimuthal anchoring energies. The fabrication of the nano‐sized groove is based on nano‐imprint lithography. Hence, the size and depth are controllable, where no random process is involved. The alignment surface is robust, stable, reliable, reproducible and suitable for mass manufacturing. Such alignment surface can be applied to fabricate a π/2 bistable twisted nematic (π/2‐BTN) display which has better optical performances than the traditional π‐BTN display.
Effect of Divalent Metal Ions on Curing Characteristics and Dynamic Mechanical Properties of Natural Rubber
Authors: Utara Songkot , Saengsila Paibool
Published: August 2015

The study examined the effects of three different divalent metal ions (Ca2+, Cu2+ and Fe2+) upon the curing characteristics and dynamic mechanical properties of vulcanised natural rubber with respect to scorch and cure times, cure rate index, storage modulus (E′) and damping peaks (tanδmax). The metal ions were added to natural rubber latex solutions at three concentrations of 20, 100 and 500 ppm, respectively. It was found that scorch and cure times increased with increasing metal ion concentration, with a decrease in cure rate index. Longer scorch and cure times were observed in the case of Cu2+, also with a lower cure rate index. Storage modulus values decreased with increasing metal ion concentration, with the exception of Ca2+, which produced the highest E′ value. The damping peaks of filled natural rubber decreased with increasing metal ion concentration. The smallest ion (Cu2+) also led to a decrease in the damping peak. The Tg of the natural rubber was unaffected by either concentration or type of metal ion.
Influence of Oxirane Ring and Phenylenediamine Structures in Modified Palm Processing Oils on Properties of ENR/PP TPVs
Authors: Thitithammawong Anoma , Nakason Charoen , Hayichelaeh Chesidi
Published: August 2015

N‐phenyl‐p‐phenylenediamine modified epoxidized palm oil (m‐EPO) was synthesized and applied as an alternative processing oil in laboratory tests of rubber compounding. The effects of added functionalities in the chemical structure of m‐EPO on the properties of ENR/PP TPVs were investigated. Palm oil (PO), epoxidized palm oil (EPO), and petroleum based white oil (WO) were used in this comparative study. The results show that oxirane rings and amine structures on N‐phenyl‐p‐phenylenediamine promoted the compatibility of processing oil with ENR molecules, due to structural similarity and interactions between polar functional groups. Furthermore, the amine structures enhanced the formation of active sulfurating agent for sulfur vulcanization. Therefore, increased torque differences with shorter cure times were observed for ENR vulcanizates with m‐EPO, relative to those of the TPVs with the other oils. Also, there were clear improvements in the tensile strength and the elongation at break stemming from the fine morphology of the vulcanized ENR particles. This indicates that the novel m‐EPO processing oil is a competitive alternative for the rubber industry in terms of its technical performance.
Glycidyl Methacrylate Grafted Polylactic Acid: Morphological Properties and Crystallization Behavior
Authors: Kangwanwatthanasiri Parina , Suppakarn Nitinat , Ruksakulpiwat Chaiwat , Ruksakulpiwat Yupaporn
Published: August 2015

In this study, physical properties of glycidyl methacrylate grafted polylactic acid (PLA‐g‐GMA) were studied and compared with those of polylactic acid (PLA). PLA‐g‐GMA was prepared by using an internal mixer. Differences in crystallization characteristics between PLA‐g‐GMA and PLA were observed from X‐ray diffraction (XRD). After applying tensile stress to PLA‐g‐GMA and PLA samples, diffraction peak (2θ) at about 29° was clearly occurred only in PLA‐g‐GMA samples. This implies that small crystals may be formed during applying tensile stress to PLA‐g‐GMA. The stress‐strain curve of PLA‐g‐GMA exhibits necking and cold drawing characteristic which was not observed in PLA. Fracture behavior in the tensile test changed from the brittle fracture of neat PLA to the ductile fracture of PLA‐g‐GMA. Fibrillar structure of PLA‐g‐GMA from tensile fractured surface were observed by scanning electron microscope (SEM). In contrast, PLA did not show fibrillar structure from SEM micrographs. From differential scanning calorimetry (DSC), PLA‐g‐GMA shows lower glass transition temperature (Tg) and crystallization temperature (Tc) than PLA. Melt crystallization during cooling was observed only from PLA‐g‐GMA. Moreover, PLA‐g‐GMA showed only one melting peak while PLA showed two melting peaks. This indicated different types of crystal forms between PLA‐g‐GMA and PLA. Crystal forms in PLA‐g‐GMA may be less perfect and can be rearranged due to higher chain flexibility during tensile stress. Thus, significantly higher elongation at break of PLA‐g‐GMA was obtained compared to that of PLA.
Silk Semi‐Interpenetrating Network Hydrogels for Biomedical Applications
Authors: Thananukul Kamonchanok , Jarruwale Pakkamon , Suttenun Nuchada , Thordason Pall , Punyamoonwongsa Patchara
Published: August 2015

The Bombyx mori silk fibroin (SF) has recently received much attention as promising hydrogel matrices due to its biocompatibility, hydrophilicity and good permeability. Beside these, porous SF is too brittle in its dry state that does not provide sufficient strength for practical use. To overcome this drawback, semi‐interpenetrating networks of SF were synthesized by a redox‐initiated reaction using poly(ethylene glycol) diacrylate (PEGa) as a precursor to form a primary network. Various hydrogel properties, including swelling ability, gelation kinetics, morphology and drug release, were evaluated through both physical and spectroscopic techniques. For all hydrogels, the gelation time, sol‐gel fraction and equilibrium water content (EWC) were found to decrease with the increasing of PEGa content. Moreover, a sustained delivery of a model compound, Rhodamine B, was also observed. This could be explained in terms of tighter interconnected network and the retardation effects mediated by SF. The proposed method had thus, demonstrated its potential use to improve performance of silk‐based materials for drug delivery applications.
New Environmentally Benign Polymers Produced by Copolymerization with α‐Angelicalactone
Authors: Tarabanko Valery E. , Kaygorodov Konstantin L.
Published: August 2015

Novel biodegradable polymer materials have been synthesised via copolymerization of styrene, or caprolactam, or ethyleneterephthalate oligomers, or methylmethacrylate with comparatively small amounts (1–20 mol. %) of α‐angelicalactone (AL) or polyangelicalactone (PAL). The molecular mass (up to 150000 amu), tensile strength (up to 170 MPa for ethyleneterephthalate‐AL copolymers), elongation at break, and yield strength of the polymers have been measured. Generally, the AL additives change the polymer strength characteristics by not more than 10–20%. Biodegradation of the synthesised polymers have been studied in the forest soil and in the composting plant wastes under conditions of anaerobic or aerobic digestion. Aerobic composting with plant wastes allows complete degradation of the AL‐containing copolymers within 9–25 weeks, except for the ethyleneterephthalate‐AL copolymers, which lose only 14–22% of the mass during 20 weeks of composting. The AL‐free homopolymers are essentially not digested under the conditions examined.
Reactive Blending of Poly(l‐lactide) and Chemically‐Modified Starch Grafted with a Maleic Anhydride‐Methyl Methacrylate Copolymer
Authors: Bunkerd Ratthaphat , Molloy Robert , Punyodom Winita , Somsunan Runglawan
Published: August 2015

Blends of poly(l‐lactide) (PLL) and chemically‐modified native cassava starch (CMS) have been prepared by melt mixing and then fabricated into thin films for property testing. The CMS was prepared by copolymerizing maleic anhydride and methyl methacrylate in solution in dimethyl sulfoxide in the presence of the dissolved starch. The objective was for the poly(maleic anhydride‐co‐methyl methacrylate), P(MAH‐co‐MMA), copolymer formed to then graft onto the starch via the reaction between its anhydride groups and the hydroxyl groups of the starch. The rationale behind this chemical modification was to improve the compatibility of the starch particles with the PLL matrix via intermolecular transesterification reactions during melt blending. As a result, the enhanced interfacial adhesion between the PLL and the CMS would lead to an improvement in mechanical properties such as tensile strength and toughness compared to the PLL blended with the unmodified native starch. This paper describes some of the results from this work.
Preparation of Surface‐Modified Silica Particles from Rice Husk Ash and Its Composites with Degradable Polylactic Acid
Authors: Opaprakasit Pakorn , Boonpa Siriporn , Jaikaew Narisara , Petchsuk Atitsa , Tangboriboonrat Pramuan
Published: August 2015

A method for preparation of silica particles from rice husk ash (RHA) is developed for use as fillers in an enhancement of gas permeability of polylactic acid (PLA) resin. Silica particles are produced in a one‐step process by employing PLA‐grafted‐chitosan copolymer (PCT) as a polymeric surfactant. Particles with an average size of ca. 30 micron, which are smaller than those obtained from a conventional method, are obtained. The major advantage of this technique is its ease of operation, in which mechanical grinding is not required. The resulting particles are then used in preparation of PLA/silica composites by varying the silica contents from 0–2.0 wt %. The PCT copolymer is present as a coating layer on the particles surface, which promotes compatibility with the PLA matrix. Gas permeability (water vapor, carbon dioxide, and oxygen) and mechanical properties of the composite films are examined. Enhancements in gas permeability and selectivity are achieved, with slight drops in mechanical properties. The materials have high potential for use as degradable packaging films with tunable gas permeability.
Hyperlipidemia‐induced hepatic and small intestine ER stress and decreased paraoxonase 1 expression and activity is associated with HDL dysfunction in Syrian hamsters
Authors: Stancu Camelia S. , Carnuta Mihaela G. , Sanda Gabriela M. , Toma Laura , Deleanu Mariana , Niculescu Loredan S. , Sasson Shlomo , Simionescu Maya , Sima Anca V.
Published: August 2015

Scope

We aimed at investigating the mechanisms linking hyperlipidemia (HL) with dysfunctional HDL and its main antioxidant enzyme, paraoxonase1 (PON1). PON1 expression and activity was determined in the small intestine, liver, and sera of normal and HL hamsters and associated with the ER stress (ERS) and the development of aortic valve lesions.

Methods and results

Male Golden Syrian hamsters were fed standard chow (N) or standard diet with 3% cholesterol and 15% butter for 16 weeks. All hamsters on fat diet developed HL, 50% also hyperglycemia (HLHG) and a fourfold increased homeostasis model assessment of insuline resistance. PON1 expression was reduced in the small intestine and liver (N > HL > HLHG) along with the increased extent of ERS, oxidized lipids, and decreased expression of liver X receptors beta (LXRβ) in the small intestine, peroxisome proliferator‐activated receptor‐γ (PPARγ) in the liver, and of the glucose transporter 4 in the myocardium. Serum PON1 levels decreased along with the increase of oxidized LDL and lesion areas of the aortic valves (N > HL > HLHG).

Conclusion

The fat diet activates the ERS and oxidative stress, decreases LXRβ, PPARγ, and PON1 in the small intestine, liver, and sera of all HL animals, in parallel with the appearance of atherosclerotic lesions in the aortic valves.
Fast experiments for structure elucidation of small molecules: Hadamard NMR with multiple receivers
Authors: Gierth Peter , Codina Anna , Schumann Frank , Kovacs Helena , Kupče Ēriks
Published: August 2015

We propose several significant improvements to the PANSY (Parallel NMR SpectroscopY) experiments—PANSY COSY and PANSY‐TOCSY. The improved versions of these experiments provide sufficient spectral information for structure elucidation of small organic molecules from just two 2D experiments. The PANSY‐TOCSY‐Q experiment has been modified to allow for simultaneous acquisition of three different types of NMR spectra—1D C‐13 of non‐protonated carbon sites, 2D TOCSY and multiplicity edited 2D HETCOR. In addition the J‐filtered 2D PANSY‐gCOSY experiment records a 2D HH gCOSY spectrum in parallel with a 1J‐filtered HC long‐range HETCOR spectrum as well as offers a simplified data processing. In addition to parallel acquisition, further time savings are feasible because of significantly smaller F1 spectral windows as compared to the indirect detection experiments. Use of cryoprobes and multiple receivers can significantly alleviate the sensitivity issues that are usually associated with the so called direct detection experiments. In cases where experiments are sampling limited rather than sensitivity limited further reduction of experiment time is achieved by using Hadamard encoding. In favorable cases the total recording time for the two PANSY experiments can be reduced to just 40 s. The proposed PANSY experiments provide sufficient information to allow the CMCse software package (Bruker) to solve structures of small organic molecules. Copyright © 2015 John Wiley & Sons, Ltd.
Refinement of the inversion‐transfer NMR experiment for faster characterization of chemical exchange
Authors: Baguet Evelyne
Published: August 2015

It is shown theoretically that the inversion‐transfer experiment used to estimate the value of unidirectional rate constants in chemical exchange systems can be performed faster via a reduction of the recovery delay. The chemical exchange rate constants can then be estimated accurately with a formula close to that of standard inversion transfer and easy to use, after a justified approximation. A function was developed to determine the optimal value of the recovery delay for an optimal inversion‐transfer sequence. The validity of these theoretical results was checked experimentally with a solution of N,N‐dimethylacetamide in which chemical exchange arises from internal hindered rotation. Copyright © 2015 John Wiley & Sons, Ltd.
Theoretical study of a simple rotational‐echo double‐resonance NMR for homonuclear spin‐1/2 pairs
Authors: Kuwahara Daisuke , Sakuragi Takahiro , Tei Chikai
Published: August 2015

We investigate theoretically intriguing aspects of a simple rotational‐echo double‐resonance (REDOR) NMR technique for homonuclear spin‐1/2 pairs undergoing MAS. The simple technique sets Gaussian soft π pulses at every half MAS rotational period in the pulse sequence. The reduction in rotational echo amplitude (the REDOR echo reduction) is observed at the end of the evolution period te = (n + 1)Tr, where Tr is a MAS rotational period. The exact average Hamiltonians for the homonuclear REDOR (hm‐REDOR) technique are calculated by dividing the evolution period into four periods. We show theoretically and experimentally that the hm‐REDOR technique produces the REDOR echo reductions for homonuclear spin‐1/2 pairs. In addition, the theoretical results reveal that the REDOR echo reductions are independent of the chemical‐shift difference, δ, under a simple condition of κ = δ/ωr ≥ 6 and te < 10 ⋅ (1/d′), where ωr is the sample spinning frequency and d′ is the dipolar coupling constant expressed in Hz. We call this simple condition the master condition. This means that the REDOR echo reductions for a homonuclear spin‐1/2 pair can be calculated under the master condition by considering only d′ and ωr, which is the case for a heteronuclear spin pair. Finally, we demonstrate that four‐phase cycling yields the multiple‐quantum filtered hm‐REDOR experiment, where the appearance of the REDOR echo reductions shows that the echo reductions are definitely attributable to the homonuclear dipolar interaction even if there is a slight unwanted effect from the recovered chemical‐shift anisotropy in these reductions. Copyright © 2015 John Wiley & Sons, Ltd.
Flammability behavior of unsaturated polyesters modified with novel phosphorous containing flame retardants
Authors: Wazarkar Kunal , Kathalewar Mukesh , Sabnis Anagha
Published: August 2015

Two phosphorous containing reactive flame retardants namely Triallyl phosphate (TAP) and diethylene glycol modified tetra‐allyl phosphate (DTAP) are synthesized and incorporated successfully in commercial Unsaturated polyester (UPR) in various amounts (5, 10, and 15 phr) to yield flame retardant unsaturated polyester (FRUPR) composites. The structures of reactive flame retardant monomers are confirmed by FTIR, 1H‐NMR, and31P‐NMR spectroscopy. Further, FRUPR composites are characterized for their mechanical, thermal, and flame retardant properties. It is observed that tensile strength and hardness of composites are enhanced with the addition of flame retardants; however, flexural strength and impact resistance are lowered. Differential Scanning Calorimetry (DSC) study reveals that there is a significant increase in glass transition temperature with the addition of flame retardants suggesting the formation of dense and crosslinked structure in FRUPR composites. Thermal stability and the flame retardant properties are also observed to be improved with the increase in concentration of flame retardant in UPR as evidenced from Thermo‐gravimetric analysis (TGA). Beyond 10 phr concentration of flame retardants, all composites show V‐0 rating on UL‐94 test. Also, increase in phosphorous content in composites leads to gradual improvement in limiting oxygen index values. POLYM. COMPOS., 38:1483–1491, 2017. © 2015 Society of Plastics Engineers
Error covariance estimation methods based on analysis residuals: theoretical foundation and convergence properties derived from simplified observation networks
Authors: Ménard Richard
Published: August 2015

We examine the theoretical foundation of the method to estimate error covariances based on analysis residuals in observation space, also known as the Desroziers method. Our analysis also includes a method based on a posteriori diagnostics of variational analysis schemes. A mathematical analysis of convergence is carried out with a simplified regular observation network, where we identify stable and unstable fixed‐point solutions, examine their rate of convergence and the conditions for convergence to the truth and compare it with maximum‐likelihood estimation. It is shown that the estimation of variance parameters converges to the truth if the error correlation is specified correctly. The convergence is much faster with the analysis increment method than with the method designed for variational analysis schemes. We also propose a combination of the Desroziers scheme and the maximum‐likelihood estimation method that could be used to estimate the spatial correlation length‐scale of observation errors. The estimation of both full observation and background‐error covariances matrices derived entirely from observation‐based residuals does not change the gain matrix, but the estimation of either one matrices is well‐defined. An analysis of the estimation of the full observation error covariance matrix using a regular observation network reveals that if all eigenvalues of the prescribed background‐error covariance are smaller than their corresponding innovation covariance eigenvalue, then the estimated error covariance converges to the truth but only if the prescribed background error is correctly specified. In the case where some eigenvalues of the background‐error covariance greatly exceed those of the innovation covariance, the convergent observation‐error matrix may become rank‐deficient. Its inverse does not exist.
Collagen-DerivedN-Acetylated Proline-Glycine-Proline in Intervertebral Discs Modulates CXCR1/2 Expression and Activation in Cartilage Endplate Stem Cells to Induce Migration and Differentiation Toward a Pro-Inflammatory Phenotype
Authors: Feng Chencheng , Zhang Yang , Yang Minghui , Huang Bo , Zhou Yue
Published: August 2015

The factors that regulate the migration and differentiation of cartilage endplate stem cells (CESCs) remain unknown. N-Acetylated proline-glycine-proline (N-Ac-PGP) is a chemokine that is involved in inflammatory diseases. The purpose of this study was to detect N-Ac-PGP in degenerative intervertebral discs (IVDs) and to determine its roles in the migration and differentiation of CESCs. Enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-mass spectrometry results indicated that the levels of the proteases that generate N-Ac-PGP as well as N-Ac-PGP levels themselves increase with the progression of IVD degeneration. Immunohistochemistry and an N-Ac-PGP generation assay demonstrated that nucleus pulposus (NP) cells generate N-Ac-PGP from collagen. The effects of N-Ac-PGP on the migration and differentiation of CESCs were determined using migration assays, RT-PCR, immunoblot analysis, and ELISA. The results showed that the expression of N-Ac-PGP receptors (CXCR1 and CXCR2) in CESCs was upregulated by N-Ac-PGP. Additionally, N-Ac-PGP induced F-actin cytoskeletal rearrangement in CESCs and increased CESC chemotaxis. Furthermore, N-Ac-PGP recruited chondrocytes and spindle-shaped cells from the cartilage endplate (CEP) into the NP in vivo. These spindle-shaped cells expressed CD105 and Stro-1 (mesenchymal stem cell markers). N-Ac-PGP induced the differentiation of CESCs toward a pro-inflammatory phenotype with increased production of inflammatory cytokines rather than toward an NP-like phenotype. Our study indicated that, in the complex microenvironment of a degenerative disc, N-Ac-PGP is generated by NP cells and induces the migration of CESCs from the CEP into the NP. N-Ac-PGP induces a pro-inflammatory phenotype in CESCs, and these cells promote the inflammatory response in degenerative discs. Stem Cells  2015;33:3558–3568
Developing interpretive power in science teaching
Authors: Rosebery Ann S. , Warren Beth , Tucker‐Raymond Eli
Published: August 2015

Early career teachers rarely receive sustained support for addressing issues of diversity and equity in their science teaching. This paper reports on design research to create a 30 hour professional development seminar focused on cultivating the interpretive power of early career teachers who teach science to students from historically non‐dominant communities. Interpretive power refers to teachers’ attunement to (a) students’ diverse sense‐making repertoires as intellectually generative in science and (b) expansive pedagogical practices that encourage, make visible, and intentionally build on students’ ideas, experiences, and perspectives on scientific phenomena. The seminar sought to integrate student sense‐making, scientific subject matter, teaching practice, and matters of equity and diversity on the same plane of professional inquiry by engaging participants in: (a) learning plant science; (b) analyzing classroom cases; (c) experimenting with expansive discourse practices in their classrooms; and (d) analyzing their classroom experiments in relation to student sense‐making and expansive pedagogy. Twenty‐eight teachers participated in two cycles of design research. An interview‐based transcript analysis task captured shifts in teachers’ interpretive power through their participation in the seminar. Findings showed that the teachers developed greater attunement to: complexity in students’ scientific ideas; the intellectual generativity of students’ sense‐making; student talk as evidence of in‐process, emergent thinking; and co‐construction of meaning in classroom discussions. Findings also showed that participants developed deeper understanding of the functions of expansive teaching practices in fostering student sense‐making in science and greater commitment to engaging in expansive practices in their classroom science discussions. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 53: 1571–1600, 2016