bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐point source pollution modelling using Soil and Water Assessment Tool and its parameter sensitivity analysis in Xin'anjiang catchment, China
Authors: Zhai Xiaoyan , Zhang Yongyong , Wang Xuelei , Xia Jun , Liang Tao
Published: December 2012

Non‐point source pollution is a key issue in integrated river basin management around the world and has resulted in water contamination, aquatic ecology deterioration and eutrophication. Xin'anjiang catchment is the key drinking water source area for Hangzhou City, China. A promising model (Soil and Water Assessment Tool) was applied to assess the non‐point source pollution and its effect on drinking water. Sensitivity analysis of model parameters was carried out using the Sequential Uncertainty Domain Parameter Fitting 2 sensitivity technique. Water discharge, sediment, total nitrogen and total phosphorus load processes from 2000 to 2010 were simulated, and the spatial distributions of non‐point source pollutants were evaluated at the catchment and administrative country levels. The results show that the hydrological parameters of the Soil and Water Assessment Tool were dominantly sensitive for non‐point source pollution simulation, including CN2, RCHRG_DP, ALPHA_BF, SOL_AWC, ESCO and SOL_K and the characteristic parameters of sub‐basins (viz. HRU_SLP and SLSUBBSN). Also, water quality parameters (viz. CH_EROD, NPERCO, RSDCO and PPERCO, PHOSKD, etc.) have a significant effect on nutrients. The model performance was very satisfactory, especially for runoff, sediment and total phosphorus simulation. The non‐point source pollutant load increased from 2001 to 2010 in the whole catchment. Total nitrogen load increased from 3428 tons (0.59 ton km−2) to 7315 tons (1.25 ton km−2), and total phosphorus load increased from 299 tons (0.05 ton km−2) to 867 tons (0.15 ton km−2). The contribution of rice land was the largest, accounting for nearly 95%, followed by tea garden (3.56%), winter wheat (1.37%), forest (0.07%) and grassland (0.02%). Moreover, She County and Xiuning County contributed more than half of the non‐point source pollutants. This study was expected to provide a method and reference for non‐point source pollution quantification and to support water quality management implementation in China. Copyright © 2012 John Wiley & Sons, Ltd.
Field assessment of surface water–groundwater connectivity in a semi‐arid river basin (Murray–Darling, Australia)
Authors: Lamontagne S. , Taylor A. R. , Cook P. G. , Crosbie R. S. , Brownbill R. , Williams R. M. , Brunner P.
Published: December 2012

In semi‐arid and arid river basins, understanding the connectivity between rivers and alluvial aquifers is one of the key challenges for the management of groundwater resources. The type of connection present (gaining, losing‐connected, transitional and losing‐disconnected) was assessed at 12 sites along six Murray–Darling Basin river reaches. The assessments were made by measuring the hydraulic head in the riparian zone near the rivers to evaluate if the water tables intersected the riverbeds and by measuring fluid pressure (ψ) in the riverbeds. The rationale for the latter was that ψ will always be greater than or equal to zero under connected conditions (either losing or gaining) and always lesser than or equal to zero under losing‐disconnected conditions. A mixture of losing‐disconnected, losing‐connected and gaining conditions was found among the 12 sites. The losing‐disconnected sites all had a riverbed with a lower hydraulic conductivity than the underlying aquifer, usually in the form of a silty clay or clay unit 0.5–2 m in thickness. The riparian water tables were 6 to 25 m below riverbed level at the losing‐disconnected sites but never lower than 1 m below riverbed level at the losing‐connected ones. The contrast in water table depth between connected and disconnected sites was attributed to the conditions at the time of the study, when a severe regional drought had generated a widespread decline in regional water tables. This decline was apparently compensated near losing‐connected rivers by increased infiltration rates, while the decline could not be compensated at the losing‐disconnected rivers because the infiltration rates were already maximal there. Copyright © 2012 John Wiley & Sons, Ltd.
Taming Multivariate Data: Conceptual and Methodological Issues
Authors: Redlinger Lawrence J. , Wiorkowski John J. , Moses Anna I.
Published: December 2012

This chapter discusses the methodological and statistical challenges in selecting appropriate peer institutions for benchmarking.
CtBP2 contributes to malignant development of human esophageal squamous cell carcinoma by regulation of p16INK4A
Authors: Guan Chengqi , Shi Hui , Wang Huijie , Zhang Jianguo , Ni Wenkai , Chen Buyou , Hou Sicong , Yang Xiaojing , Shen Aiguo , Ni Runzhou
Published: December 2012

C‐terminal binding protein‐2 (CtBP2), as a transcriptional co‐repressor, has been shown to mediate the repression of p16INK4A, a tumor suppressor gene product, in primary human cells. Here we aimed to investigate how the correlation between CtBP2 and p16INK4A influenced the development of esophageal squamous cell carcinoma (ESCC). Immunohistochemistry of ESCC tissue sections indicated that the CtBP2 and p16INK4A expressions were inversely correlated to each other with a linear regression coefficient of −0.747 (P < 0.05), and Western blot analysis revealed that CtBP2 was higher expressed in tumorous tissues than in adjacent non‐tumorous tissues. Either CtBP2 or p16INK4A expression was significantly related to histological differentiation (P = 0.016 or 0.001) and to the expression of Ki‐67, a proliferating marker (P = 0.006 or 0.02), and patients with higher CtBP2 and lower p16INK4A expressions had shorter overall survival. We also observed that CtBP2 modulated the cell proliferation and cell cycle in ECA109 cells, an ESCC cell line, by inhibiting p16INK4A. Overexpression or knockdown of CtBP2 in ECA109 cells was found to inhibit or activate the mRNA or protein expression of p16INK4A, which in turn altered the cell proliferation and cell cycle in ECA109 cells, as measured by flow cytometry and cell count assay. Additionally, after ECA109 cells silenced for CtBP2 were treated with cisplatin (an anti‐ESCC agent), the p16INK4A expression was up‐regulated, and the cell apoptosis was promoted, thus confirming the repression of p16INK4A by CtBP2. Collectively, all results suggested that CtBP2 might contribute to the progression of ESCC through a negative transcriptional regulation of p16INK4A. J. Cell. Biochem. 114: 1343–1354, 2013. © 2013 Wiley Periodicals, Inc.
Disruption of immune regulation by microbial pathogens and resulting chronic inflammation
Authors: Barth Kenneth , Remick Daniel G. , Genco Caroline A.
Published: December 2012

Activation of the immune response is a tightly regulated, coordinated effort that functions to control and eradicate exogenous microorganisms, while also responding to endogenous ligands. Determining the proper balance of inflammation is essential, as chronic inflammation leads to a wide array of host pathologies. Bacterial pathogens can instigate chronic inflammation via an extensive repertoire of evolved evasion strategies that perturb immune regulation. In this review, we discuss two model pathogens, Mycobacterium tuberculosis and Porphyromonas gingivalis, which efficiently escape various aspects of the immune system within professional and non‐professional immune cell types to establish chronic inflammation. J. Cell. Physiol. 228: 1413–1422, 2013. © 2012 Wiley Periodicals, Inc.
Characterization of WWOX inactivation in murine mammary gland development
Authors: Abdeen Suhaib K. , Salah Zaidoun , Khawaled Saleh , Aqeilan Rami I.
Published: December 2012

The WW domain‐containing oxidoreductase (WWOX) is commonly inactivated in multiple human cancers, including breast cancer. Wwox null mice die prematurely precluding adult tumor analysis. Nevertheless, aging Wwox‐heterozygous mice at C3H genetic background develop higher incidence of mammary tumors. We recently generated a Wwox conditional knockout mouse in which loxp sites flank exon 1 in the Wwox allele and showed that total ablation of WWOX in these mice resembles that of conventional targeting of Wwox. Here, we report the characterization of WWOX ablation in mouse mammary gland using MMTV‐Cre transgenic line. We demonstrated that WWOX ablation leads to impaired mammary ductal growth. Moreover, targeted deletion of WWOX is associated with increased levels of fibronectin, a component of the extracellular matrix. In addition, we showed that shRNA knockdown of WWOX in MCF10A breast epithelial cells dramatically increased fibronectin and is associated with enhanced cell survival and impaired growth in three‐dimensional culture Matrigel assay. Taken together our results are consistent with a critical role for WWOX in normal breast development and tumorigenesis. J. Cell. Physiol. 228: 1391–1396, 2013. © 2012 Wiley Periodicals, Inc.
Advancement of Criminal Profiling Methods in Faceted Multidimensional Analysis
Authors: Goodwill Alasdair M. , Stephens Skye , Oziel Sandra , Sharma Shankari , Allen Jared C. , Bowes Nicola , Lehmann Robert
Published: December 2012

The current study seeks to advance the faceted multidimensional scaling (termed FMDS) procedure used in much of the investigative psychology research. To this end, recent research on street robbery by Goodwill and colleagues will be utilised to illustrate the effectiveness of a facet scale method for offender profiling. Four FMDS themes of street robbery (Con, Blitz, Confrontation and Snatch) were revealed by the crossing of two underlying axial facets: the offenders' level of violence and interaction with the victim. The facet scale method, utilising offenders' axial facet scores, was compared to previous count, proportional and centroid classification methods in the prediction of offender criminal histories. Utilising logistic regression and receiver operating characteristic analyses, the axial facet scale method was found to significantly outperform the qualitatively based dominant theme classification methods that typically employ angular and radial facets for FMDS interpretation. Implications for the use of axial facet scales within FMDS analysis for offender profiling research are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Clinical use of brain volumetry
Authors: Giorgio Antonio , De Stefano Nicola
Published: December 2012

Magnetic resonance imaging (MRI)‐based brain volumetry is increasingly being used in the clinical setting to assess brain volume changes from structural MR images in a range of neurologic conditions. Measures of brain volumes have been shown to be valid biomarkers of the clinical state and progression by offering high reliability and robust inferences on the underlying disease‐related mechanisms. This review critically examines the different scenarios of the application of MRI‐based brain volumetry in neurology: 1) supporting disease diagnosis, 2) understanding mechanisms and tracking clinical progression of disease, and 3) monitoring treatment effect. These aspects will be discussed in a wide range of neurologic conditions, with particular emphasis on Alzheimer's disease and multiple sclerosis. J. Magn. Reson. Imaging 2012. ©2012 Wiley Periodicals, Inc.
Changes in reactive oxygen species production and antioxidant enzyme activity of Agaricus bisporus harvested at different stages of maturity
Authors: Liu Jun , Wu Yu‐chun , Kan Juan , Wang Yan , Jin Chang‐hai
Published: December 2012

Background

The edible mushroom Agaricus bisporus is more prone to senescence than most other vegetables. However, the senescence of A. bisporus before harvesting is often ignored. In this study the changes in reactive oxygen species (ROS) production and antioxidant enzyme activity of A. bisporus harvested at four different stages of maturity were investigated.

Results

The firmness of A. bisporus decreased from 6.22 to 5.12 N. Respiration rate increased from 540.65 to 609.82 mg CO2 kg−1 fresh weight (FW) h−1. Browning degree increased from 0.42 to 0.71, showing a positive correlation with polyphenol oxidase activity. For ROS production, superoxide radical production rate increased from 0.51 to 1.16 nmol g−1 FW s−1. Hydrogen peroxide content increased from 0.81 to 1.39 nmol g−1 FW and then decreased rapidly to 0.68 nmol g−1 FW. Malondialdehyde content increased from 1.58 to 2.64 nmol g−1 FW. For antioxidant enzymes, superoxide dismutase and peroxidase activities decreased significantly at stage 4, whereas a significant increase in catalase activity was found at stages 3 and 4.

Conclusions

The balance between ROS and antioxidants was destroyed at stage 4, causing extensive senescence of mushroom tissues. Thus A. bisporus should be harvested at stage 3.© 2012 Society of Chemical Industry
Olive oil quality and ripening in super‐high‐density Arbequina orchard
Authors: Benito Marta , Lasa José Manuel , Gracia Pilar , Oria Rosa , Abenoza María , Varona Luis , Sánchez‐Gimeno Ana Cristina
Published: December 2012

Background

The aim of this work was to evaluate the evolution of the quality of extra virgin olive oil obtained from a super‐high‐density Arbequina orchard, under a drip irrigation system, throughout the ripening process. For this objective, physicochemical, nutritional and sensory parameters were studied. In addition, the oxidative stability, pigment content and colour evolution of olive oil were analysed during the ripening process.

Results

Free acidity increased slightly throughout the ripening process, while peroxide value and extinction coefficient decreased. Total phenol content and oxidative stability showed a similar trend, increasing at the beginning of ripening up to a maximum and thereafter decreasing. α‐Tocopherol and pigment contents decreased with ripening, leading to changes in colour coordinates. Sensory parameters were correlated with total phenol content, following a similar trend throughout the maturation process.

Conclusion

By sampling and monitoring the ripeness index weekly, it would be possible to determine an optimal harvesting time for olives according to the industrial yield and the physicochemical, nutritional and sensory properties of the olive oil. © 2012 Society of Chemical Industry
Chemical composition and flavour characteristics of a liquid extract occurring as waste in crab (Ovalipes punctatus) processing
Authors: Bu Junzhi , Dai Zhiyuan , Zhou Tao , Lu Yanbin , Jiang Qianqian
Published: December 2012

BACKGROUND

The crab processing industry has generated a considerable quantity of by‐products, and these untapped residues resulted in environmental problem and waste of natural resources. Therefore, the purpose of this research was to evaluate the further usage potential of Ovalipes punctatus extract. The proximate composition, minerals, fatty acids, amino acids, tasty components (free amino acid, flavour 5′‐nucleotides, glycine betaine and inorganic ions) and volatile flavour components were studied.

RESULTS

O. punctatus extract was found to have a high protein (31.2 g kg−1), but a low fat content (0.13 g kg−1). The protein contained high amounts of arginine (110.2 g kg−1 protein) and glutamic acid (108.9 g kg−1). The fatty acid profiles were dominated by saturated fatty acids, while C20 n‐3 and n‐6 fatty acids accounted for 85% of its polyunsaturated fatty acids. Arginine, alanine, glycine, glycine betaine, glutamic acid and chloridion (taste active value greater than 1) were primary taste‐active components. A total of 77 volatiles were identified, and benzaldehyde and pyrazines were the major flavour contributors to the aroma of O. punctatus extract. Furthermore, sensory evaluation with a five‐point hedonic scale showed that the overall flavour of O. punctatus extract had high acceptance.

CONCLUSION

Results presented in this study indicated that O. punctatus extract could be utilised to produce nutritious food or value‐added products. © 2013 Society of Chemical Industry
Implementation and optimisation of a high‐temperature loading strategy of liquid standards in the quantification of volatile organic compounds using solid sorbents
Authors: Rodríguez‐Navas Carlos , Forteza Rafael , Cerdà Víctor
Published: December 2012

High‐temperature liquid standard loading strategy onto solid sorbent traps for calibration of thermal desorption–GC–MS techniques for the analysis of volatile organic compounds is evaluated and optimised. With this proposed set‐up, volatilised liquid‐loaded standards interact in gas phase with solid sorbent particles. Response factor for 15 volatile compounds with different vapour pressures have been evaluated and compared with common strategies based on liquid matrix interactions. Using gas matrix strategy improves signal output in the range 10–700%. Average increase for benzene, toluene, ethylbenzene and xylenes is 480%. Reported systematic bias between liquid standards and gas samples are reduced, enhancing thermal desorption methodologies on one of its more important issues. In addition, the proposed system improves the average repeatability to a 3.2%, over 13 times some reported data. The use of an ultra‐thin GC capillary column of 150 μm id performs better peak resolution in about 60% the time with usual 250 μm id capillary columns. The usefulness of this proposed optimised procedure has been proved in real air matrix samples, through a large study with the reliable characterisation of 93 different volatile compounds in the ambient air of a municipal solid waste treatment area
Parameters optimization of supercritical fluid‐CO2 extracts of frankincense using response surface methodology and its pharmacodynamics effects
Authors: Zhou Jing , Ma Xing‐miao , Qiu Bi‐Han , Chen Jun‐xia , Bian Lin , Pan Lin‐mei
Published: December 2012

The volatile oil parts of frankincense (Boswellia carterii Birdw.) were extracted with supercritical carbon dioxide under constant pressure (15, 20, or 25 MPa) and fixed temperature (40, 50, or 60°C), given time (60, 90, or 120 min) aiming at the acquisition of enriched fractions containing octyl acetate, compounds of pharmaceutical interest. A mathematical model was created by Box‐Behnken design, a popular template for response surface methodology, for the extraction process. The response value was characterized by synthetical score, which comprised yields accounting for 20% and content of octyl acetate for 80%. The content of octyl acetate was determined by GC. The supercritical fluid extraction showed higher selectivity than conventional steam distillation. Supercritical fluid‐CO2 for extracting frankincense under optimum condition was of great validity, which was also successfully verified by the pharmacological experiments.
Simultaneous quantitation of seven pyrethroid metabolites in human urine by capillary gas chromatography–mass spectrometry
Authors: Tao Lin , Chen Mei , Collins Erin , Lu Chensheng
Published: December 2012

Pyrethroid insecticides are applied in the residential environment, as well as in agricultural crops, for insect control purpose. We developed and validated an accurate, sensitive, and reproducible analytical method to simultaneously detect seven pyrethroid metabolites, namely, 3‐(2,2‐dichlorovinyl)‐2,2‐dimethyl‐(1‐cyclopropane) carboxylic acid, 3‐(2,2‐dibromovinyl)‐2,2‐dimethyl‐(1‐cyclopropane) carboxylic acid, 3‐phenoxybenzoic acid, 4‐fluoro‐3‐phenoxybenzoic acid, 2‐methyl‐3‐phenylbenzoic acid, 4‐chloro‐α‐isoproply benzeneacetic acid, and 3‐(2‐chloro‐3,3,3‐trifluoroprop‐1‐enyl)‐2,2‐dimethylcyclopropanecarboxylic acid, in human urine. This method employs deconjugation with enzyme, SPE using Agilent C18 cartridges on a RapidTrace SPE workstation, derivatization using hexafluoro isopropanol and N,N′‐diisopropylcarbodiimide, and compounds separation and identification on GC–MS. The detection limits of seven metabolites were 0.02–0.08 ng/mL in urine. The recoveries of seven metabolites were 81–104%, 85–99%, and 83–99% in urine specimens fortified at 0.1, 0.4, and 3.2 ng/mL concentrations, respectively. The overall coefficient of variation was 4.3–10.8% in two quality control specimens which were repeatedly measured during a period of 2 months. This method was applied to urine samples collected from children living in Boston, MA. The median concentrations of six detected pyrethroid metabolites ranged from 0.06 to 0.86 ng/mL in urine.
In‐band pumped Ti:Tm:LiNbO3 waveguide amplifier and low threshold laser
Authors: George Mathew , Ricken Raimund , Quiring Viktor , Sohler Wolfgang
Published: December 2012

The fabrication by diffusion doping and a detailed optical investigation of a Ti:Tm:LiNbO3 waveguide amplifier and of a Fabry‐Pérot type Ti:Tm:LiNbO3 laser are reported. Both devices are in‐band pumped by a laser diode at 1650 nm. The wave‐guide amplifier shows broad‐band optical gain in the wavelength range 1750 nm < λ < 1900 nm. The laser emits at 1890 nm, the longest emission wavelength of a Tm:LiNbO3 laser reported so far; also 1850 nm emission could be demonstrated. Laser threshold (1890 nm) is at 4 mW coupled pump power; the slope efficiency is ∼13.3%. Properties and potential of both devices are analyzed by extensive modeling.
Penultimate Unit and Solvent Effects on 2:1 Sequence Control During Radical Copolymerization of N‐Phenylmaleimide With β‐Pinene
Authors: Yamamoto Daisuke , Matsumoto Akikazu
Published: December 2012

Copolymers with a 2:1 regulated sequence of N‐phenylmaleimide with β‐pinene units (AAB‐type repeating units) are produced during radical copolymerization. The monomer reactivity ratios are determined using the penultimate unit model, and it is demonstrated that they vary depending on the solvent used (tetrahydrofuran, 1,2‐dichloroethane, 2,2,2‐trifluoroethanol, and perfluoro‐tert‐butanol) and the copolymerization temperature (0–100 °C). The interaction of the PhMI repeating units with solvents lead to the production of the 2:1 controlled sequence and a significant change in the relative reactivity of the PhMI radicals by polar and steric effects.
Conformational Behavior of Conjugated Polymers With Oligo(phenylene vinylene) Side Chains
Authors: Peeters Helmuth , Koeckelberghs Guy
Published: December 2012

The synthesis and chiroptical properties of a series of meta‐arylenes, equipped with chiral oligo(phenylene vinylene) (OPV) side chains, are presented. How the OPV side chain contributes to the optical properties of the polymer is investigated. Secondly, the influence of the distance of the chiral moieties, placed on the OPV side chain, to the polymer main chain is investigated, which shows that, in order to induce any chiral effects, these chiral moieties need to be placed in the ß‐position near the polymer main chain. Finally, it is shown that long (a)chiral, lateral alkoxy chains on the OPV side chain prevent the polymers from adopting a helical conformation and result in the formation of lateral (a)chiral stacks of different polymer chains.
Selective Wetting and Localization of Silica in Binary and Ternary Blends Based on Styrene Butadiene Rubber, Butadiene Rubber, and Natural Rubber
Authors: Le Hong Hai , Keller Melanie , Hristov Martin , Ilisch Sybill , Xuan Tung Hoang , Do Quang Khang , Pham Tung , Stöckelhuber Klaus‐Werner , Heinrich Gert , Radusch Hans‐Joachim
Published: December 2012

In the present work, the wetting concept was further developed for explanation of the kinetics of silica localization in binary and ternary rubber blends in the first mixing period. In the second mixing period when the wetting process is finished, a re‐localization process of silica within the blend phases takes place until an equilibrium state is reached. Material effects and mixing conditions on the silica localization were systematically characterized. A comparison between the kinetics of filler localization experimentally determined by the wetting concept, and the filler localization at an equilibrium theoretically predicted by our Z‐model, provides a deeper insight into the filler transfer process taking place during the mixing process.
Green Processing of Nanofibers for Regenerative Medicine
Authors: Krishnan Ranganathan , Sundarrajan Subramanian , Ramakrishna Seeram
Published: December 2012

Electrospinning of polymer scaffolds is mostly carried out using organic solvents, but the drawbacks are: solvent costs, environmental hazards, and presence of traces of solvent impurities. The use of water‐soluble polymers (WSPs), water or aqueous solutions as an electrospinning medium (green processing) is a very attractive method to avoid such issues. However, a few WSP such as polyelectrolytes are not spinnable as such, but have been electrospun by addition of WSPs, additives, and salts. This paper covers solution properties, polyelectrolyte nanofibrous scaffolds (polysaccharides, biopolymers, etc.), fabrication through green processing, and their regenerative medical applications such as wound dressing, drug delivery, and tissue engineering. This is the first review to cover the above issues, the drawbacks of current methods, and future challenges.
Modified Diblock Copolymer Bearing Fluoro Groups and Evaluation of its Hydrophobic Properties
Authors: Politakos N. , Kortaberria G. , Zalakain I. , Avgeropoulos A. , Mondragon I.
Published: December 2012

Summary: The major scope of the presented work is the characterization and evaluation of hydrophobicity of novel copolymers of the PS‐b‐PB1,2 type, modified with perfluorooctanoyl chloride [PS: polystyrene, PB1,2: poly(butadiene) with 100% 1,2‐microstructure]. Fluoro atoms in polymers can create hydrophobic surfaces with low surface energy. The fluorinated groups can migrate and possible orient in the outermost surface of the polymeric thin film. Characterization in the modified block copolymer was conducted with carbon nuclear magnetic resonance (13C‐NMR) and thermogravimetric analysis (TGA) to evaluate the structure. Contact angle measurements were also conducted to verify the hydrophobicity of the fluorinated copolymer. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to depict the structure of the material. The obtained results showed that indeed the fluorinated copolymer exhibits high hydrophobicity (low surface energy material) with significant structural differences from its precursor.
Synthesis and Characterization of Nanostructures: MWCNTf/TiO2 and MWCNTf/TiO2/HAp
Authors: Albano C. , Sarmiento Y. , González G.
Published: December 2012

Summary: In the present work nanostructured systems based on multiwalled carbon nanotubes (MWCNT) coated with titania (TiO2), hydroxyapatite (HAp) and their combinations were synthesized using sol‐gel and precipitation methods. Different synthesis variables were used (calcination, concentration of MWCNT and gel aging time). The TiO2 nanoparticles size was 4.4 nm, independent of the synthesis conditions. The best coating was obtained by aging the gel during 20 days. Also the use of the surfactant SDS resulted in a good dispersion of the HAp particles on the MWCNT walls. HAp increases the thermal stability of MWCNTs.
Study of Different Mixing Sequences in Polymer Blends Reinforced with Nano‐Clays
Authors: Pastor J. M. , Gallego R. , Basurto F. C. , Núñez K. , García‐López D. , Merino J. C.
Published: December 2012

Summary: Different polymer blends reinforced with nano‐clay were prepared by melt compounding. The influence of four different sequences on the microstructural and thermomechanical properties has been analyzed. Polyamide 6–ethylene‐propylene‐diene monomer (PA6/EPDM) blends were the most thermally stable of all showing that nano‐clay dispersion in the continuous phase (NB1) produced the best balanced properties. On the other hand, in polycarbonate–(acrylonitrile‐butadiene‐styrene) (PC/ABS) blends the nano‐clay addition on the dispersed phase (NB2) led to an increase in stiffness and HDT with a low value of toughness. Finally, the best properties (impact strength and HDT) in poly (lactic acid)–low density polyethylene (PLA/LDPE) blends were obtained when all the materials were blended in one step (NB3).
Shape Memory Polyurethanes Based on Polyols Derived From Renewable Resources
Authors: Corcuera M. A. , Saralegi A. , Fernández‐d'Arlas B. , Mondragon I. , Eceiza A.
Published: December 2012

Summary: Segmented polyurethanes have been synthesized employing polyols derived from renewable resources, semicrystalline or amorphous in nature, as soft segment, and an aliphatic (1,6‐hexamethylene diisocyanate, HDI) or aromatic (4,4′‐diphenylmethane diisocyanate, MDI) diisocyanate and 1,4‐butanediol (BD) as hard segment using two‐step bulk polymerization procedure. The effect of soft and hard segment structure and hard segment content on thermal, mechanical and shape memory properties has been studied by means of differential scanning calorimetry, tensile tests and tensile tests performed using a thermal chamber.
Use of Rice Husk as Filler in Flexible Polyurethane Foams
Authors: Navarro M. V. , Vega‐Baudrit J. R. , Sibaja M. R. , Melero F. J.
Published: December 2012

Summary: In this study, flexible polyether polyurethane foams were synthesized by using two kinds of fillers: Inorganic filler and vegetal fiber obtained from agricultural waste. Structural, thermal and mechanical properties of the obtained foams were analyzed.
Quality in Cooperatives versus Investor‐owned Firms: Evidence from Broiler Production in Paraná, Brazil
Authors: Cechin Andrei , Bijman Jos , Pascucci Stefano , Zylbersztajn Decio , Omta Onno
Published: December 2012

Organizational economics points to the weaknesses of cooperatives in producing high‐quality products compared with investor‐owned firms (IOFs). In the Brazilian broiler industry, suppliers delivering to a cooperative are performing better on quality than suppliers to an IOF. Data was collected through a survey among suppliers of one cooperative and two IOFs. What could explain the cooperative's advantage in terms of suppliers' quality performance? Results show that there are important differences regarding relationship characteristics such as dependence, behavioral uncertainty, market risk reduction, and adaptation support, which could account for the higher quality products of the cooperative farmers. Copyright © 2012 John Wiley & Sons, Ltd.
Evolving Functions of Interorganizational Governance Mechanisms
Authors: Sánchez José M. , Vélez María L. , Álvarez‐Dardet Concha
Published: December 2012

Through a longitudinal case study, this article examines the evolution of the twofold function of formal governance mechanisms, for control and coordination, as an interorganizational relationship evolves. We ask whether all formal governance tools develop simultaneously, or whether each mechanism is designed and used for only one function; whether different mechanisms' attributes foster one function rather than the other; and whether different mechanisms are developed over time in order to provoke both functions' evolution. Finally, we explore whether the interorganizational relationship evolution in part explains the evolution of the two functions, or vice versa. Copyright © 2012 John Wiley & Sons, Ltd.
PPARα modulates the TSH β‐subunit mRNA expression in thyrotrope TαT1 cells and in a mouse model
Authors: Wege Nicole , Schutkowski Alexandra , König Bettina , Brandsch Corinna , Weiwad Matthias , Stangl Gabriele I.
Published: December 2012

Scope

Fasting leads to a significant downregulation of the hypothalamus‐pituitary‐thyroid axis, and peroxisome proliferator‐activated receptor (PPAR) α is a key transcription factor in mediating a magnitude of adaptive responses to fasting. In this study, we examined the role of PPARα in regulation of the hypothalamus‐pituitary‐thyroid axis.

Methods and results

Thyroid‐stimulating hormone β‐subunit (TSHβ) mRNA abundance was being reduced in response to treatment of TαT1 cells with PPARα agonists (p < 0.05), indicating an inhibitory transcriptional regulation of TSHβ by PPARα. As expected, fasting significantly downregulated TSHβ mRNA expression in a two‐factorial study with fed or fasted wild‐type (WT) and PPARα knockout mice (p < 0.05). In contrast to the in vitro data, fasted PPARα knockout mice revealed lower mRNA concentrations of pituitary TSHβ (−64%) and TSH‐regulated thyroid genes, and lower plasma concentrations of thyroxine (T4, −25%), triiodothyronine (T3, −25%), free T4 (−60%), and free T3 (−35%) than fasted WT mice (p < 0.05). Those differences were not observed in fed mice.

Conclusions

Data from thyrotrope cells revealed that PPARα could contribute to the fasting‐associated downregulation of the TSHβ mRNA expression. In a mouse model, fasting led to a significant reduction in TSHβ mRNA level, but unexpectedly this effect was stronger in mice lacking PPARα than in WT mice.
The Effects of California's Paid Family Leave Program on Mothers’ Leave‐Taking and Subsequent Labor Market Outcomes
Authors: Rossin‐Slater Maya , Ruhm Christopher J. , Waldfogel Jane
Published: December 2012

This analysis uses March Current Population Survey data from 1999 to 2010 and a differences‐in‐differences approach to examine how California's first in the nation paid family leave (PFL) program affected leave‐taking by mothers following childbirth, as well as subsequent labor market outcomes. We obtain robust evidence that the California program doubled the overall use of maternity leave, increasing it from an average of three to six weeks for new mothers—with some evidence of particularly large growth for less advantaged groups. We also provide evidence that PFL increased the usual weekly work hours of employed mothers of 1‐ to 3‐year‐old children by 10 to 17 percent and that their wage incomes may have risen by a similar amount.
INCREASING TEACHER TREATMENT INTEGRITY THROUGH PERFORMANCE FEEDBACK PROVIDED BY SCHOOL PERSONNEL
Authors: Hagermoser Sanetti Lisa M. , Fallon Lindsay M. , Collier‐Meek Melissa A.
Published: December 2012

When implementing behavioral interventions in educational settings, some implementers need support to maintain high levels of treatment integrity. Performance feedback has a large body of research supporting it as a strategy for improving teachers’ implementation of classroom interventions. However, in most prior studies, performance feedback has been delivered by a researcher, not by a school staff member, which limits generalizability of results to applied settings. In this study, school personnel (i.e., internal consultants) assessed teachers’ treatment integrity when implementing a classwide behavioral intervention and, when low, provided performance feedback. Further, researchers assessed internal consultants’ treatment integrity and provided performance feedback as needed. Results indicate that internal consultants are able to assess and briefly increase teachers’ treatment integrity with performance feedback, although some teachers needed more support than did others. Likewise, internal consultants’ treatment integrity was fairly high initially, but required consistent performance feedback to increase treatment integrity levels toward the end of the study. Implications for research and practice are discussed.
Beta‐blockers may reduce intrusive thoughts in newly diagnosed cancer patients
Authors: Lindgren Monica E. , Fagundes Christopher P. , Alfano Catherine M. , Povoski Stephen P. , Agnese Doreen M. , Arnold Mark W. , Farrar William B. , Yee Lisa D. , Carson William E. , Schmidt Carl R. , Kiecolt‐Glaser Janice K.
Published: December 2012

Objective

A cancer diagnosis provokes significant levels of emotional distress, with intrusive thoughts being the most common manifestation among breast cancer survivors. Cancer‐related intrusive thoughts can take the form of emotional memories, flashbacks, nightmares, and intrusive images. Emotional arousal after a severe life stressor prolongs adrenergic activation, which in turn may increase risk for post‐traumatic symptomatology. However, antihypertensive beta‐blockers block adrenergic activation and are known to reduce traumatic memories and related psychological distress. Thus, the current study examined the association between beta‐blocker use and the severity of cancer‐related intrusive thoughts and related symptoms following a cancer diagnosis.

Methods

The 174 breast and 36 female colorectal cancer patients who had recently undergone diagnostic screening or biopsy included 39 beta‐blocker users and 171 non‐users. Prior to any cancer treatment including surgery, participants completed questionnaires that included the Impact of Events Scale and the Center for Epidemiological Studies Depression Scale. Analyses controlled for age, education, cancer stage, cancer type, days since diagnosis, marital status, depression, and comorbidities.

Results

Although the high rates of cancer‐related distress in this sample were similar to those of other studies with recently diagnosed patients, beta‐blocker users endorsed 32% fewer cancer‐related intrusive thoughts than non‐users.

Conclusions

Recently diagnosed cancer patients using beta‐blockers reported less cancer‐related psychological distress. These results suggest that beta‐blocker use may benefit cancer patients' psychological adjustment following diagnosis, and provide a promising direction for future investigations on the pharmacological benefits of beta‐blockers for cancer‐related distress. Copyright © 2012 John Wiley & Sons, Ltd.
Improved hole distribution in InGaN/GaN dual‐wavelength light‐emitting diodes with Mg‐doped quantum‐wells
Authors: Si Zhao , Wei Tongbo , Yan Jianchang , Ma Jun , Zhang Ning , Liu Zhe , Wei Xuecheng , Wang Xiaodong , Lu Hongxi , Wang Junxi , Li Jinmin
Published: December 2012

A study on the effect of Mg doping in quantum‐well (QW) layers on dual‐wavelength light‐emitting diodes (LEDs) was performed. A series of dual‐wavelength LEDs with different Mg doping conditions were fabricated. According to electroluminescence measurement, as the Mg doping concentration and regions varied, improved hole distribution and bottom‐QW emission was achieved. This result is in accord with APSYS simulation. In addition, the sample with Mg doping in all QWs showed the highest output power and smallest efficiency droop. It is concluded that Mg doping in QWs could ameliorate the optical and electrical properties of dual‐wavelength LEDs.
The physical principles of terahertz silicon lasers based on intracenter transitions
Authors: Pavlov S. G. , Zhukavin R. Kh. , Shastin V. N. , Hübers H.‐W.
Published: December 2012

The first silicon laser was reported in the year 2000. It is based on impurity transitions of the hydrogen‐like phosphorus donor in monocrystalline silicon. Several lasers based on other group‐V donors in silicon have been demonstrated since then. These lasers operate at low lattice temperatures under optical pumping by a midinfrared laser and emit light at discrete wavelengths in the range from 50 to 230 µm (between 1.2 and 6.9 THz). Dipole‐allowed optical transitions between particular excited states of group‐V substitutional donors are utilized for donor‐type terahertz (THz) silicon lasers. Population inversion is achieved due to specific electron–phonon interactions of the impurity atom. This results in long‐living and short‐living excited states of the donor centers. Another type of THz laser utilizes stimulated resonant Raman‐type scattering of photons by a Raman‐active intracenter electronic transition. By varying the pump‐laser frequency, the frequency of the Raman intracenter silicon laser can be continuously changed between at least 4.5 and 6.4 THz. The gain of the donor and Raman‐type THz silicon lasers is of the order of 0.5 to 10 cm−1, which is similar to the net gain realized in THz quantum cascade lasers and infrared Raman silicon lasers. In addition, fundamental aspects of the laser process provide new information about the peculiarities of electronic capture by shallow impurity centers in silicon, lifetimes of nonequilibrium carriers in excited impurity states, and electron–phonon interaction.
Measurement of oxygen chemical diffusion in PuO2‐x and analysis of oxygen diffusion in PuO2‐x and (Pu,U)O2‐x
Authors: Kato Masato , Uchida Teppei , Sunaoshi Takeo
Published: December 2012

Oxygen chemical diffusion in PuO2‐x was investigated in the temperature range of 1473‐1873 K by thermogravimetry as functions of oxygen‐to‐metal (O/M) ratios and temperatures. The oxygen chemical diffusion coefficients, $ \tilde D $ were determined assuming that the reduction curves were dominated by a diffusion process. The O/M ratio and Pu content dependence on the chemical diffusion coefficients were evaluated. The chemical diffusion coefficient had its minimum value at around O/M=1.98 and decreased with increasing Pu content in (U,Pu)O2‐x. The self‐diffusion coefficients were evaluated. A model for describing the relationship among O/M ratio, oxygen chemical diffusion, and self‐diffusion was proposed based on defect chemistry. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles modeling of the H color centers in MgF2 crystals
Authors: Dauletbekova Alma , Abuova Fatima , Akilbekov Abdirash , Kotomin Eugene , Piskunov Sergey
Published: December 2012

MgF2 with a rutile structure is important wide‐gap optical material with numerous applications. We present and discuss the results of calculations for basic hole defects – interstitial F atoms (called also the colour H centers). This study is based on the large scale ab initio DFT calculations using hybrid B3PW exchange‐correlation functional as implemented into CRYSTAL computer code. The electronic structure, atomic geometry, charge density distribution are calculated and compared with similar defects in CaF2 fluorite. It is shown that the H centers oriented nearly parallel to the (110) axis are energetically more favourable than those oriented along the (001) axis, in agreement with experiment. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative study of TL and EPR properties of four solid solutions of garnets
Authors: Rocca Rene R. , Watanabe Shigueo , Barbosa Renata F. , Cano Nilo F. , Tatumi Sonia H.
Published: December 2012

In the present work four solid solutions of peralspite garnets indicated PP, PS, R and A have been investigated as to their TL properties. The glow curves of PP, PS, R and A irradiated by gamma rays with dose from 10 to 1000 Gy (2000 in A) presented peaks around 150, 200, 260 and 360‐370 °C, but the response of these peaks to radiation doses varies from sample to sample. Also we present glow curves when samples were annealed at 500 °C for 30 min and irradiated to UV light. In other experiments samples irradiated to 1000 Gy were exposed to UV light; the TL intensity decreases under UV exposure. OSL measurements show a linear growth with radiation dose below 200 Gy. Almost straight line signal is obtained for EPR spectrum of natural PS sample. The change in the shape of EPR spectrum of PS sample annealed at high temperature in the range 800 to 1000 °C indicates that Fe2+ converts to Fe3+. This is confirmed by Molecular Absorption Spectroscopy measurements. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microstructure and microprecipitation in copper‐doped soda‐lime silicate glass
Authors: Suszynska Maria , Krajczyk Ludwina , Cizman Agnieszka , Serafinczuk Jaroslaw
Published: December 2012

The process of ion exchange was used to introduce copper ions into a commercial soda lime silicate glass, the composition of which corresponds to the miscibility gap in the SiO2‐Na2O system. After exchange, the samples have been thermally treated in a gaseous hydrogen atmosphere. The optical absorption of divalent copper and the concentration profiles of the exchanged (Na) and exchanging (Cu) ions are determining the effectiveness of both processes. The behaviour of the dopant in the glassy matrix has been studied on the basis of thermal expansion and X‐ray diffraction measurements as well as the transmission electron microscopy observations of the composite material. It has been stated that hydrogenation of suitably exchanged specimens could be an effective procedure for obtaining glass ceramics with nanoparticles of metallic copper and semi‐conducting copper oxide embedded in the glassy matrix also in the form of core‐shell structures. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Multi‐Targeted Effects of Chrysanthemum Herb Extract Against Escherichia coli O157:H7
Authors: Kim Ki‐Suk , Lim Dong Jin , Yang Hea Jung , Choi Eun‐Kyeong , Shin Min Hee , Ahn Kwang Seok , Jung Sang Hoon , Um Jae Young , Jung Hee‐Jae , Lee Jun Hee , Lee Seok‐Geun , Jung Sung‐Ki , Jang Hyeung‐Jin
Published: December 2012

The Chrysanthemum lavandulifolium extract, which includes chrysoeriol, sudachitin, and acacetin, has excellent antibiotic effects on Escherichia coli O157:H7 (E. coli O157). A notable point is that the antibiotic targets of the herb extract are similar to the targets of commonly used antibiotic drugs, including bacterial cell wall biosynthesis, bacterial protein synthesis, and bacterial DNA replication and repair. In addition, the herbal antibiotic inhibits the etiological factors that contribute to the pathogenic property. The herbal sample was extracted and fractionated and then inoculated through a disk diffusion method to confirm its antibiotic effect against E. coli O157. Total RNA was isolated from the affected bacterial cells, and its expression level was analyzed through a microarray analysis. To confirm the accuracy of the microarray data, a real‐time PCR was performed. Three active compounds, chrysoeriol, sudachitin, and acacetin, were identified with a high‐performance liquid chromatography‐electrospray ionization/mass spectrometry chromatogram, and the disk diffusion study confirmed that chrysoeriol and sudachitin contribute to the antibiotic properties of the herb extract. The results demonstrate that the multi‐target efficacy of the herbal sample may indicate the potential for the development of more effective and safer drugs that will act as substitutes for existing antibiotics. Copyright © 2012 John Wiley & Sons, Ltd.
Process Control for the Vector Autoregressive Model
Authors: Cheng Tsung‐Chi , Hsieh Ping‐Hung , Yang Su‐Fen
Published: December 2012

Multivariate monitoring techniques for serially correlated observations have been widely used in various applications. This study examines several issues that have arisen in relation to the statistical quality control for the vector autoregressive (VAR) model, using a Monte Carlo approach. Different versions of the Hotelling T2 statistic and control limits to monitor the VAR‐type process for both Phase I and Phase II schemes can be specified for different sample sizes and configurations of the model. Our simulation study suggests that the Hotelling's T2 statistic can be tested against the χ2 critical values during Phase I, but should be tested against scaled F critical values during Phase II. An unbiased covariance estimate of residuals is also recommended during Phase II when sample size is typically small. By reanalyzing some real data examples, the authors offer new conclusions. Copyright © 2012 John Wiley & Sons, Ltd.