bluuebunny/crossref_metadata_2025 huggingface dataset:
Aberrant signaling pathways of the lung mesenchyme and their contributions to the pathogenesis of bronchopulmonary dysplasia
Authors: Ahlfeld Shawn K. , Conway Simon J.
Published: November 2011

Bronchopulmonary dysplasia (BPD) is a chronic lung disease in infants born extremely preterm, typically before 28 weeks' gestation, characterized by a prolonged need for supplemental oxygen or positive pressure ventilation beyond 36 weeks postmenstrual age. The limited number of autopsy samples available from infants with BPD in the postsurfactant era has revealed a reduced capacity for gas exchange resulting from simplification of the distal lung structure with fewer, larger alveoli because of a failure of normal lung alveolar septation and pulmonary microvascular development. The mechanisms responsible for alveolar simplification in BPD have not been fully elucidated, but mounting evidence suggests that aberrations in the cross‐talk between growth factors of the lung mesenchyme and distal airspace epithelium have a key role. Animal models that recapitulate the human condition have expanded our knowledge of the pathology of BPD and have identified candidate matrix components and growth factors in the developing lung that are disrupted by conditions that predispose infants to BPD and interfere with normal vascular and alveolar morphogenesis. This review focuses on the deviations from normal lung development that define the pathophysiology of BPD and summarizes the various candidate mesenchyme‐associated proteins and growth factors that have been identified as being disrupted in animal models of BPD. Finally, future areas of research to identify novel targets affected in arrested lung development and recovery are discussed. Birth Defects Research (Part A), 2012. © 2011 Wiley Periodicals, Inc.
Substrate perturbation alters the glycoside hydrolase activities and community composition of switchgrass‐adapted bacterial consortia
Authors: Gladden John M. , Eichorst Stephanie A. , Hazen Terry C. , Simmons Blake A. , Singer Steven W.
Published: November 2011

Bacteria modulate glycoside hydrolase expression in response to the changes in the composition of lignocellulosic biomass. The response of switchgrass‐adapted thermophilic bacterial consortia to perturbation with a variety of biomass substrates was characterized to determine if bacterial consortia also responded to changes in biomass composition. Incubation of the switchgrass‐adapted consortia with these alternative substrates produced shifts in glycoside hydrolase activities and bacterial community composition. Substantially increased endoglucanase activity was observed upon incubation with microcrystalline cellulose and trifluororacetic acid‐pretreated switchgrass. In contrast, culturing the microbial consortia with ionic liquid‐pretreated switchgrass increased xylanase activity dramatically. Microbial community analyses of these cultures indicated that the increased endoglucanase activity correlated with an increase in bacteria related to Rhodothermus marinus. Inclusion of simple organic substrates in the culture medium abrogated glycoside hydrolase activity and enriched for bacteria related to Thermus thermophilus. These results demonstrate that the composition of biomass substrates influences the glycoside hydrolase activities and community composition of biomass‐deconstructing bacterial consortia. Biotechnol. Bioeng. 2012; 109:1140–1145. © 2011 Wiley Periodicals, Inc.
Increased matrix synthesis by fibroblasts with decreased proliferation on synthetic chitosan–gelatin porous structures
Authors: Iyer Pooja , Walker Kenneth J. , Madihally Sundararajan V.
Published: November 2011

Influence of mechanical characteristics and matrix architecture of substrates used in cell culture is an important issue to tissue engineering. Chitosan‐based materials have been processed into porous structures, injectable gels and membranes, and are investigated to regenerate various tissues. However, the effect of these structures on cell growth and matrix production in accordance with each of the differing scaffolds has not been examined. We investigated the influence of porous structures, hydrogels, and membranes on the growth of normal human fibroblasts and their matrix production in a serum‐free system. We used chitosan alone and in combination with gelatin. Injectable hydrogels were prepared using 2‐glycerol phosphate. From the same solution, porous scaffolds and membranes were formed using controlled rate freezing and lyophilization, and air‐drying, respectively. Fibroblast growth was evaluated on the 4th and 10th days using flow cytometry and CFDA‐SE pre‐staining. Cell morphology was assessed using actin and nucleus staining. Total protein content, collagen, tropoelastin, and MMP2/MMP‐9 activity in the media supernatant were assessed by BCA, Sircol™, Fastin Elastin, and fluorogeneic peptide assays. Collagen accumulated in the matrix was assessed by Sircol™ assay after pepsin/acetic acid digestion and by Masson's Trichrome staining. These results showed increased viability of fibroblasts on chitosan–gelatin porous scaffold with decreased proliferation relative to tissue culture plastic (TCP) surface despite the cells showing spindle shape. The total protein, collagen, and tropoelastin contents were higher in the spent media from chitosan–gelatin porous scaffolds compared to other conditions. MMP2/MMP9 activity was comparable to TCP. An increase in collagen content was also observed in the matrix, suggesting increased matrix deposition. In summary, matrix production is influenced by the form of chitosan structures, which significantly affects the regenerative process. Biotechnol. Bioeng. 2012; 109:1314–1325. © 2011 Wiley Periodicals, Inc.
Particle‐in‐Cell Simulation for the Effect of Segmented Electrodes Near the Exit of an Aton‐Type Hall Thruster on Ion Focusing Acceleration
Authors: Yu D. R. , Qing S. W. , Liu H. , Li H.
Published: November 2011

The effect of floating conductive electrodes near the channel exit of an Aton‐type Hall thruster on ion focusing acceleration is studied by simulating the two‐dimensional plasma flow with a fully kinetic Particle‐in‐Cell method for the gas flow rate ja ranged in 1∼3 mg/s. Numerical results show that low‐emissive electrodes can reduce plume divergence if the electrode length is less than 2 mm due to the low secondary electron emissive characteristic, but widen plume in all the gas flow rate range if the electrode length is greater than 2mm since the conductive property of segmented electrodes trends to make equipotential lines convex toward channel exit and is even parallel to the wall surface in the near‐wall region. Further investigation predicts that the combination of high emissive dielectric wall and segmented low‐emissive dielectric wall is a promising way to reduce plume divergence (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Clock gene variation in Tachycineta swallows
Authors: Dor Roi , Cooper Caren B. , Lovette Irby J. , Massoni Viviana , Bulit Flor , Liljesthrom Marcela , Winkler David W.
Published: November 2011

Many animals use photoperiod cues to synchronize reproduction with environmental conditions and thereby improve their reproductive success. The circadian clock, which creates endogenous behavioral and physiological rhythms typically entrained to photoperiod, is well characterized at the molecular level. Recent work provided evidence for an association between Clock poly‐Q length polymorphism and latitude and, within a population, an association with the date of laying and the length of the incubation period. Despite relatively high overall breeding synchrony, the timing of clutch initiation has a large impact on the fitness of swallows in the genus Tachycineta. We compared length polymorphism in the Clock poly‐Q region among five populations from five different Tachycineta species that breed across a hemisphere‐wide latitudinal gradient (Fig. 1). Clock poly‐Q variation was not associated with latitude; however, there was an association between Clock poly‐Q allele diversity and the degree of clutch size decline within breeding seasons. We did not find evidence for an association between Clock poly‐Q variation and date of clutch initiation in for any of the five Tachycineta species, nor did we found a relationship between incubation duration and Clock genotype. Thus, there is no general association between latitude, breeding phenology, and Clock polymorphism in this clade of closely related birds.

Photos of Tachycineta swallows that were used in this study: A) T. bicolor from Ithaca, New York, B) T. leucorrhoa from Chascomús, Argentina, C) T. albilinea from Hill Bank, Belize, D) T. meyeni from Puerto Varas, Chile, and E) T. thalassina from Mono Lake, California, Photographers: B: Valentina Ferretti; A, C‐E: David Winkler.

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Sexual selection on song and cuticular hydrocarbons in two distinct populations of Drosophila montana
Authors: Veltsos Paris , Wicker‐Thomas Claude , Butlin Roger K. , Hoikkala Anneli , Ritchie Michael G.
Published: November 2011

Sexual selection has the potential to contribute to population divergence and speciation. Most studies of sexual selection in Drosophila have concentrated on a single signaling modality, usually either courtship song or cuticular hydrocarbons (CHCs), which can act as contact pheromones. We have examined the relationship between both signal types and reproductive success using F1–3 offspring of wild‐collected flies, raised in the lab. We used two populations of the Holarctic species Drosophila montana that represent different phylogeographic clades that have been separate for ca. 0.5 million years (MY), and differ to some extent in both traits. Here, we characterize the nature and identify the targets of sexual selection on song, CHCs, and both traits combined within the populations. Three measures of courtship outcome were used as fitness proxies. They were the probability of mating, mating latency, and the production of rejection song by females, and showed patterns of association with different traits that included both linear and quadratic selection. Courtship song predicted courtship outcome better than CHCs and the signal modalities acted in an additive rather than synergistic manner. Selection was generally consistent in direction and strength between the two populations and favored males that sang more vigorously. Sexual selection differed in the extent, strength, and nature on some of the traits between populations. However, the differences in the directionality of selection detected were not a good predictor of population differences. In addition, a character previously shown to be important for species recognition, interpulse interval, was found to be under sexual selection. Our results highlight the complexity of understanding the relationship between within‐population sexual selection and population differences. Sexual selection alone cannot predict differences between populations.
Effect of land use and topography on spatial variability of soil moisture in a gully catchment of the Loess Plateau, China
Authors: Huang Yilong , Chen Liding , Fu Bojie , Huang Zhilin , Gong Jie , Lu Xixi
Published: November 2011

The Loess Plateau ecosystem in China is degraded owing to poor natural conditions and intense human activity. The intensity of soil erosion and deficit of soil moisture are the key factors that influence the ecological restoration and agricultural land productivity in this region. Analysis of the soil moisture dynamic and the relative importance of land use and topography for the spatial variability of soil moisture is the basis for guiding ecosystem restoration and agricultural development. We analysed the spatial variability of soil moisture for five land‐use types within 44 sample plots (176 sample points) at the five depths (0–20, 20–40, 40–60, 60–80 and 80–100 cm) in the Anjiagou catchment of the Loess Plateau from April to September 2002. The depth‐averaged soil moisture of cropland was the highest among the five land‐use types, followed by fallowland, woodland, shrubland and wasteland during high soil–water contents period (from 24 April to 23 June). The time‐averaged soil moisture of all the five land‐use types first decreased with depth during the wet moisture status and then increased with depth during the dry conditions (from 12 July to 9 August). The time‐averaged soil moisture of fallowland, cropland and shrubland was decreased with depth, but both wasteland and woodland was decreased and then increased with depth in the medium moisture status (from 23 August to 18 September). Land use was the key factor that influenced the spatial variability of the time‐averaged moisture of the four soil layers (20–40, 40–60, 60–80 and 80–100 cm) during the wet and medium soil–water content condition. Land use had a weak influence on the spatial variability of the time‐averaged moisture of all the five soil layers in the dry moisture status. Slope aspect had a significant influence on the time‐averaged soil moisture of some soil layers in the wet and medium moisture statuses for wasteland, shrubland, woodland and fallowland. The other four topographic factors (slope profile curvature, slope position, relative elevation and slope gradient) all had weak influence on the time‐averaged soil moisture of all the five land use types in the three water statuses. Copyright © 2011 John Wiley & Sons, Ltd.
Liquid‐phase‐based separation systems for depletion, prefractionation and enrichment of proteins in biological fluids and matrices for in‐depth proteomics analysis – An update covering the period 2008–2011
Authors: Selvaraju Subhashini , El Rassi Ziad
Published: November 2011

This review article expands on the previous one (Jmeian, Y. and El Rassi, Z. Electrophoresis 2009, 30, 249–261) by reviewing pertinent literature in the period extending from early 2008 to the present. Similar to the previous review article, the present one is concerned with proteomic sample preparation (e.g. depletion of high‐abundance proteins, reduction of the protein dynamic concentration range, enrichment of a particular subproteome), and the subsequent chromatographic and/or electrophoretic prefractionation prior to peptide separation and identification by LC‐MS/MS. This review article differs from the first version published in Electrophoresis 2009, 30, 249–261 by expanding on capturing/enriching subglycoproteomics by lectin affinity chromatography. Ninety‐eight articles published in the period extending from early 2008 to the present have been reviewed. By no means is this review article exhaustive: its aim is to give a concise report on the latest developments in the field.
Tin‐containing layered double hydroxides: Synthesis and application in poly(vinyl chloride) cable formulations
Authors: Zheng Xiaoran , Cusack Paul A.
Published: November 2011

Layered double hydroxides (LDHs) and Sn‐containing LDHs have been synthesized using a co‐precipitation method, and the resulting products have been characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FTIR) and Brunauer‐Emmett‐Teller(BET) surface area measurement, clearly showing that Sn‐containing LDH hybrids have been successfully prepared. TEM shows the ‘house‐of‐cards’ structure of the Sn‐LDHs produced, resulting from the edge‐to‐face interaction of the LDH layers. Higher tin levels lead to an additional magnesium hydroxystannate, MgSn(OH)6, (‘MHS’) phase that is present in the form of approximately 40‐nm cubic particles in an LDH/MHS hybrid structure. FTIR and XRD suggest that, at low levels of Sn, the Sn4+may exist in the form of amorphous hydrated tin(IV) oxide rather than being incorporated into the LDH lattice. These powders have been compounded into poly(vinyl chloride) (PVC), and their fire performance has been evaluated using limited oxygen index and cone calorimeter techniques. Peak rate of heat release and smoke parameter can be reduced by 64% and 81%, respectively, when replacing 10 wt% of the primary ATH fire‐retardant filler by the synthesized Sn‐LDHs, while keeping the total fire‐retardant loading at 100 phr. Thermogravimetric analysis indicates that Sn‐LDH is an effective char promoter for PVC. Copyright © 2011 John Wiley & Sons, Ltd.
Sifting the wheat from the chaff: prioritizing GWAS results by identifying consistency across analytical methods
Authors: Oldmeadow Christopher , Riveros Carlos , Holliday Elizabeth G. , Scott Rodney , Moscato Pablo , Wang Jie Jin , Mitchell Paul , Buitendijk Gabrielle H.S. , Vingerling Johannes R. , Klaver Caroline C.W. , Klein Ronald , Attia John
Published: November 2011

The curse of multiple testing has led to the adoption of a stringent Bonferroni threshold for declaring genome‐wide statistical significance for any one SNP as standard practice. Although justified in avoiding false positives, this conservative approach has the potential to miss true associations as most studies are drastically underpowered. As an alternative to increasing sample size, we compare results from a typical SNP‐by‐SNP analysis with three other methods that incorporate regional information in order to boost or dampen an otherwise noisy signal: the haplotype method (Schaid et al. [2002] Am J Hum Genet 70:425–434), the gene‐based method (Liu et al. [2010] Am J Hum Genet 87:139–145), and a new method (interaction count) that uses genome‐wide screening of pairwise SNP interactions. Using a modestly sized case‐control study, we conduct a genome‐wide association studies (GWAS) of age‐related macular degeneration, and find striking agreement across all methods in regions of known associated variants. We also find strong evidence of novel associated variants in two regions (Chromosome 2p25 and Chromosome 10p15) in which the individual SNP P‐values are only suggestive, but where there are very high levels of agreement between all methods. We propose that consistency between different analysis methods may be an alternative to increasingly larger sample sizes in sifting true signals from noise in GWAS. Genet. Epidemiol. 2011. © 2011 Wiley Periodicals, Inc. 35:745‐754, 2011
Multivariate drought characteristics using trivariate Gaussian and Student t copulas
Authors: Ma Mingwei , Song Songbai , Ren Liliang , Jiang Shanhu , Song Jiali
Published: November 2011

This study aims to investigate the changing properties of drought events in Weihe River basin, China, by modeling the multivariate joint distribution of drought duration, severity and peak using trivariate Gaussian and Student t copulas. Monthly precipitations of Xi'an gauge are used to illustrate the meta‐elliptical copula‐based methodology for a single‐station application. Gaussian and Student t copulas are found to produce a better fit comparing with other six symmetrical and asymmetrical Archimedean copulas, and, checked by the goodness‐of‐fit tests based on a modified bootstrap version of Rosenblatt's transformation, both of them are acceptable to model the multivariate joint distribution of drought variables. Gaussian copula, the best fitting, is employed to construct the dependence structures of positively associated drought variables so as to obtain the multivariate joint and conditional probabilities of droughts. A Kendall's return period (KRP) introduced by Salvadori and De Michele (2010) is then adopted to assess the multivariate recurrent properties of drought events, and its spatial distributions indicate that prolonged droughts are likely to break out with rather short recurrence intervals in the whole region, while drought status in the southeast seems to be severer than the northwest. The study is of some merits in terms of multivariate drought modeling using a preferable copula‐based method, the results of which could serve as a reference for regional drought defense and water resources management. Copyright © 2011 John Wiley & Sons, Ltd.
Validation of an immunohistochemical signature predictive of 8‐year outcome for patients with breast carcinoma
Authors: Charpin Colette , Tavassoli Fattaneh , Secq Véronique , Giusiano Sophie , Villeret Julia , Garcia Stéphane , Birnbaum Daniel , Bonnier Pascal , Lavaut Marie‐Noëlle , Boubli Léon , Carcopino Xavier , Iovanna Juan
Published: November 2011

We recently reported that standardized quantitative immunohistochemical (IHC) assays allowed prediction of an adverse outcome among 572 node negative (N−) patients with breast carcinoma (BrCa). To further validate our prior findings, we repeated the IHC stains including a second series of BrCa diagnosed at Yale University. Tissue microarrays (TMAs) of two cohorts of patients with BrCa (418 Marseille University and 303 Yale University) were respectively investigated for IHC expression of 15 markers (HIF‐1α, PI3K, pAKT, pmTOR, moesin, P21, 4EBP‐1, P27, Ker5‐6, pMAPKAPK‐2, SHARP2, claudin‐1, ALDH, AF6 and CD24). Quantitative measurements of immunoprecipitates densitometry assessed with an image analyzer were correlated with 8‐year patients' outcome and compared in the two cohorts. The best predictive signature consisted of a combination of five markers that included HIF‐1α, PI3K, claudin‐1, AF6 and pAKT in N− BrCa. This combination permitted an accurate prediction of outcome in 92.34% (386/418) of N− patients in the first set (Marseille) and 89.8% (158/176) in the second set (Yale). The close results in both cohorts confirmed the validity of this original IHC signature predictive of prognosis in node negative BrCa. This validation suggests that in clinical practice, it would be possible with standardized kits (i) to identify patients with poor prognosis at diagnosis time, particularly in the N− BrCa subset, who would require more aggressive adjuvant therapy and (ii) to avoid useless expensive therapies and their side effects in N− patients with favorable prognosis.
Antibacterial effect and cytotoxicity of Ag‐doped functionally graded hydroxyapatite coatings
Authors: Bai Xiao , Sandukas Stefan , Appleford Mark , Ong Joo L. , Rabiei Afsaneh
Published: November 2011

Functionally graded hydroxyapatite coatings (FGHA) doped with 1, 3, and 6.5 wt % silver (Ag) have been deposited on Titanium using ion‐beam‐assisted deposition. Scanning transmission electron microscopy on coating cross sections confirmed the presence of FGHA coating with mostly amorphous layers at the top and mostly crystalline layers toward the coating interface as well as the existence of 10–50 nm Ag particles distributed throughout the thickness of the coatings. Calcium release in phosphate buffered saline solution showed a high release rate of Ca at the beginning of the test, and a gradual decrease in release rate thereafter to a minimum level until day 7. Similarly, the release rate of Ag in ultra pure water was initially high in the first 4 h and then gradually decreased over a 7 days period. Antibacterial tests have shown a reduction in the viability of S. aureus in Ag‐doped coatings particularly in samples with higher Ag concentrations of 3 and 6.5 wt %. Cytotoxicity tests using an osteoblast cell line, on the other hand, have demonstrated that the samples with 6.5 wt % Ag have a negative effect on osteoblast cell response, proliferation, and apoptosis as well as a negative effect on protein and osteocalcin production. It is notable that the samples with 3 wt % Ag or less presented minimal cytotoxicity compared with control surfaces. Considering both the antibacterial and cytotoxicity effects, it is suggested that the 3 wt % of Ag in FGHA coatings can be favorable. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 553–561, 2012.
Patients' diverse beliefs about what happens at the time of death
Authors: Perkins Henry S. , Cortez Josie D. , Hazuda Helen P.
Published: November 2011

BACKGROUND:

Beliefs about what happens at the time of death surely affect a patient's whole dying experience and could help guide end‐of‐life care. Yet virtually no research describes those beliefs. This exploratory study begins the descriptive process.

METHODS:

Assuming culture is key, we interviewed 26 Mexican‐American (MA), 18 Euro‐American (EA), and 14 African‐American (AA) inpatients about their beliefs concerning what happens at the time of death.

RESULTS:

One belief, that death separates the dead from the living, was widespread. Majorities of all 3 ethnic group samples and of 5 of the 6 gender subsamples expressed this belief, saying the dead “go” or “leave” from this life. Other beliefs differed by ethnic group or gender. For example, more EAs (50%) than others said death is a momentary event, and more MAs (35%) than others said death involves “being taken” by an external force (always God or Jesus). Furthermore, considerably more EA women (45%) than others said some senses persist after death. In contrast, the physiologic signs that participants cited as defining the exact time of death varied from individual to individual with no ethnic or gender pattern, and no one sign predominated.

CONCLUSIONS:

A few beliefs about what happens at the time of death may characterize Americans in general; many other beliefs may characterize only certain ethnic groups, genders, or individuals. To identify such beliefs and to use them to guide end‐of‐life care, hospitalists and other health professionals may have to elicit them directly from patients or survivors. Journal of Hospital Medicine 2012. © 2011 Society of Hospital Medicine
Functional resurfacing of the palm: Flap selection based on defect analysis
Authors: Engelhardt T.O. , Rieger U.M. , Schwabegger A.H. , Pierer G.
Published: November 2011

Extensive defect coverage of the palm and anatomical reconstruction of its unique functional capacity remains difficult. In manual laborers, reconstruction of sensation, range of motion, grip strength but also mechanical stability is required. Sensate musculo‐/fasciocutaneous flaps bear disadvantages of tissue mobility with shifting/bulkiness under stress. Thin muscle and fascial flaps show adherence but preclude sensory nerve coaptation. The purpose of this review is to present our algorithm for reliable selection of the most appropriate procedure based on defect analysis. Defect analysis focusing on units of tactile gnosis provides information to weigh needs for sensation or soft tissue stability. We distinguish radial unit (r)‐thenar, ulnar unit (u)‐hypothenar and unit (c)‐central plus distal palm. Individual parameters need similar consideration to choose adequate treatment. Unit (r) and unit (u) are regions of secondary touch demanding protective sensation. Restoration of sensation using neurovascular, fasciocutaneous flaps is recommended. In unit (c), tactile gnosis is of less, mechanical resistance of greater value. Reconstruction of soft tissue resistance is suggested first in this unit. In laborers, free fascial‐ or muscle flaps with plantar instep skin grafts may achieve near to anatomical reconstruction with minimal sensation. Combined defects involving unit (c) require correlation with individual parameters for optimal flap selection. Defect coverage of the palm should not consist of merely providing sensate vascularized tissue. The most appropriate procedure should be derived from careful defect analysis to achieve near to anatomical reconstruction. In laborers, defect related demands need close correlation with sensation and mechanical stability to be expected. © 2011 Wiley Periodicals, Inc. Microsurgery, 2012.
Who volunteers? Constructing a hybrid theory
Authors: Einolf Christopher , Chambré Susan M.
Published: November 2011

This paper describes three major theoretical perspectives in research on volunteering: social theories that stress the importance of context, roles, and integration; individual characteristic theories that emphasize values, traits, and motivations; and resource theories that focus on skills and free time. It unites research from multiple disciplines into a single hybrid model, performs a preliminary test of the model on a nationally representative US dataset, and concludes with recommendations for scholars and practitioners. Using the 1995 Midlife in the US dataset, we operationalized concepts from each theoretical category and found that variables measuring each perspective played a substantial and independent role in predicting volunteering. Our hybrid model, which includes significant variables from each theory, offers some directions for recruitment and retention by showing how social roles and networks can constrain or encourage volunteering at different stages of the life course. As social roles and networks are both highly predictive and easily observed, volunteer managers can use them to recruit and retain volunteers. Copyright © 2011 John Wiley & Sons, Ltd.
From solicitation to search: a study of monitoring costs as a driver of donor giving behavior in online portal websites
Authors: Wardell Clarence , Ashley Shena R.
Published: November 2011

This study focuses on market contexts, in particular online giving portals, where donors are able to search and select organizations to contribute to instead of responding to solicitations. To understand donor behavior in this context, we construct and test a two‐stage donor search model. A relationship between the behavior of the donor and that of the charitable organization is sought along two dimensions: how organizational behavior involving the reduction of monitoring costs affects the amount that a donor gives and the likelihood that donors will make a subsequent contribution. Copyright © 2011 John Wiley & Sons, Ltd.
Study on a parameter to express glass‐forming relationship of phenolic–novolac resin
Authors: Guo Kai , Bian Xiufang , Li Zhonghao , Qin Jingyu
Published: November 2011

Chemoviscosity and glass‐forming ability of commercial phenolic–novolac resin are investigated at hexamethylenetramine (HMTA) curing agent content weight from 6 to 9%. We propose a parameter, Mk, which is based on chemoviscosity change rate and Tg0 of uncured liquid resin, to predict glass‐forming ability of the fully cured phenolic–novolac resin. It is found that Mk has a negative linear relationship with Tg∞, and the lower Mk represents the better glass‐forming ability of initial phenolic–novolac uncured liquid resin while the higher Tg∞ represents the better glass‐forming ability of fully cured resin. Further more, Mk establishes a kinetic glass‐forming relationship between liquid uncured and fully cured phenolic–novolac resin in terms of comparing with Tg∞. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers
Synergistic effect between a triazine‐based macromolecule and melamine pyrophosphate in flame retardant polypropylene
Authors: Lai Xuejun , Zeng Xingrong , Li Hongqiang , Liao Feng , Yin Changyu , Zhang Haili
Published: November 2011

A novel charring agent, namely triazine‐based macromolecule (TBM), was synthesized via solution polycondensation of cyanuric chloride, ethanolamine, and diethylenetriamine. The prepared charring agent possessed little water solubility and superior char‐forming ability, and it showed good synergistic effects with melamine pyrophosphate (MPP) in flame retardant polypropylene (PP). When the content of MPP was 16.7 wt% and TBM was 8.3 wt%, the limiting oxygen index (LOI) of the PP/MPP/TBM composite could reach 31.0%, and a UL‐94 V‐0 rating was achieved based on the vertical burning test. Furthermore, the composite exhibited an outstanding water resistance that it could still obtain a V‐0 rating after soaking in hot water for 168 h. The cone calorimetry test (CCT) results demonstrated that the peak heat release rate (PHRR), the total heat release (THR) and mass lose rate (MLR) of the composite were decreased significantly in comparison with those of pure PP. The thermogravimetric analysis (TGA), thermogravimetry‐Fourier transform infrared spectrometry (TG‐FTIR), and scanning electron microscopy‐energy dispersive spectra (SEM‐EDS) results revealed that the efficient flame retardancy of MPP/TBM was mainly attributed to the formation of a compact and thermostable intumescent char on underlying materials during a fire. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers
Towards realization of a large‐area light‐emitting diode‐based solar simulator
Authors: Hamadani B. H. , Chua K. , Roller J. , Bennahmias M. J. , Campbell B. , Yoon H. W. , Dougherty B.
Published: November 2011

Solar simulators based on light‐emitting diodes (LEDs) have shown great promise as alternative light sources for indoor testing of photovoltaic cells with certain characteristics that make them superior to the traditional solar simulators. However, large‐area uniform illumination more suitable for larger cells and module measurements still remain a challenge today. In this paper, we discuss the development and fabrication of a scalable large‐area LED‐based solar simulator that consists of multiple tapered light guides. We demonstrate fine intermixing of many LED light rays and power delivery in the form of a synthesized AM 1.5 spectrum over an area of 25 cm × 50 cm with better than 10% spatial nonuniformity. We present the spectral output, the spatial uniformity, and the temporal stability of the simulator in both the constant current mode and the pulsed‐mode LED operation, and compare our data with the International Electrotechnical Commission standards on solar simulators for class rating. Although the light intensity with our current design and settings falls short of the standard solar AM 1.5 intensity, this design and further improvements open up the possibility of achieving large‐area, high‐power indoor solar simulation with various desired spectra. Copyright © 2011 John Wiley & Sons, Ltd.
Photovoltaics literature survey (No. 90)
Authors: Shrestha Santosh
Published: November 2011

In order to help keep readers up‐to‐date in the field each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics, and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Santosh Shrestha at s.shrestha@unsw.edu.au. Copyright © 2011 John Wiley & Sons, Ltd.
SET‐LRP of methyl acrylate to complete conversion with zero termination
Authors: Nguyen Nga H. , Levere Martin E. , Percec Virgil
Published: November 2011

The single electron transfer‐living radical polymerization of methyl acrylate (MA) initiated by bis(2‐bromopropionyl)ethane (BPE) in dimethyl sulfoxide was carried out to 100% monomer conversion and complete absence of bimolecular termination under the following reaction conditions: [MA]/[BPE]/[Me6‐TREN]/[CuBr2] = 60/1/0.21/0.01 and [MA]/[BPE]/[TREN]/[CuBr2] = 60/1/0.25/0.05. These polymerizations were mediated by 0.5 cm of hydrazine‐activated Cu(0) wire of 20 gauge (0.812 cm in diameter), corresponding to a surface area of 0.14 cm2 of Cu(0) per 3 mL reaction volume (2/1 v/v monomer/solvent). A higher extent of bimolecular termination (5–13%) was observed at complete conversion when longer lengths of Cu(0) wire were used. In the absence of CuBr2 the activated Cu(0) wire/Me6‐TREN catalyst in dimethyl sulfoxide also allowed the synthesis of perfectly bifunctional and monofunctional PMAs at complete conversion. This was also demonstrated by the quantitative reinitiation experiments from the chain(s) end(s) of these macroinitiators. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
First‐principles studies of structural and electronic properties of layered C3N phases
Authors: Hu Qianku , Wu Qinghua , Wang Haiyan , He Julong , Zhang Guanglei
Published: November 2011

The structural and electronic properties of layered C3N compound have been studied using ab initio pseudopotential density‐functional method within the local‐density approximation. Total energy, lattice constant, band structure, and electron density of state are calculated. Among three possible C3N monolayer configurations, the monolayer‐I structure with the highest symmetry is the most stable and predicted to be a narrowgap semiconductor with an indirect gap about 0.283 eV. Among four possible C3N stacking configurations constructed from hexagonal BN and graphite structures, C3N‐IV constructed from hexagonal BN is expected to be the most stable structure and has metallic conducting behavior. The structural stability of layered C3N has also been checked by the calculations of the formation energies, elastic constants, and phonon frequencies.
Effectiveness of a Multidisciplinary Worksite Stress Reduction Programme for Women
Authors: Werneburg Brooke L. , Herman Lacie L. , Preston Heather R. , Rausch Sarah M. , Warren Beth A. , Olsen Kerry D. , Clark Matthew M.
Published: November 2011

It has been well established that a high level of stress is associated with medical problems, mental health difficulties and absenteeism at the workplace. The aim of this single‐arm study design was to examine the potential effectiveness of a 12‐session multidisciplinary stress reduction programme on reducing perceived stress and improving health behaviours and quality of life. One hundred and four women participated in a programme that incorporated group support, skill building and cognitive behavioural and relaxation techniques. A series of Bonferroni corrected t‐tests found that the participants reported having significantly (p < 0.001) lower levels of perceived stress, improved health behaviours (sleep, nutrition, physical activity) improved overall health and improved quality of life at the end of the 12 week programme and at 1‐month follow‐up. Although the effect sizes for improvement were all large, there was no control group, so regression to the mean or selection bias may have impacted the results. Therefore, these results provide initial support for the implementation of gender‐based worksite stress reduction programmes and provide guidance in designing an effective worksite stress reduction programme. Further research using randomized controlled trials is warranted. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of Emotional Disclosure in Caregivers: Moderating Role of Alexithymia
Authors: Ashley Laura , O'Connor Daryl B. , Jones Fiona
Published: November 2011

Caregivers have been found to experience high levels of depression and anxiety. This study explored the efficacy of two writing interventions aimed at reducing psychological distress in informal caregivers and examined the moderating effects of alexithymia. Caregivers (N = 150) were randomly assigned to (1) write about the stress related to being a caregiver, (2) write about positive life experiences or (3) write about a control topic for 20 min on 3 days at home. Depression and anxiety symptoms were assessed at baseline, 2 weeks, 2 months and 6 months post‐intervention. Analysis of variance for a mixed design revealed no main effects of writing condition on the follow‐up measures. However, among caregivers with lower scores on alexithymia, those who wrote about positive experiences reported less anxiety and/or depression on follow‐ups at 2 weeks, at 2 months and at 6 months. Moreover, in the control condition, less anxiety was reported by caregivers with lower scores on alexithymia at 2 weeks and at 6 months. No effects of stress disclosure were observed; therefore, writing about caregiver stress should not be encouraged in this vulnerable group. These findings highlight the importance of examining moderating factors, such as individual differences variables as well as exploring the efficacy of alternative writing interventions. Copyright © 2011 John Wiley & Sons, Ltd.
Feature location in source code: a taxonomy and survey
Authors: Dit Bogdan , Revelle Meghan , Gethers Malcom , Poshyvanyk Denys
Published: November 2011

Feature location is the activity of identifying an initial location in the source code that implements functionality in a software system. Many feature location techniques have been introduced that automate some or all of this process, and a comprehensive overview of this large body of work would be beneficial to researchers and practitioners. This paper presents a systematic literature survey of feature location techniques. Eighty‐nine articles from 25 venues have been reviewed and classified within the taxonomy in order to organize and structure existing work in the field of feature location. The paper also discusses open issues and defines future directions in the field of feature location. Copyright © 2011 John Wiley & Sons, Ltd.
II. WHOSE RULE OF LAW? AN ANALYSIS OF THE UK'S DECISION NOT TO OPT-IN TO THE EU ASYLUM PROCEDURES AND RECEPTION CONDITIONS DIRECTIVES
Authors: Stefanelli Justine N
Published: November 2011

The United Kingdom (‘UK’) has indicated its intention not to opt-in to two proposals from the European Commission aimed at further developing the Common European Asylum System through the replacement of existing instruments on asylum procedures and reception conditions. The purpose of the European Union (‘EU’) amendment process is to establish rules that more closely align the legal framework for asylum in the Member States so that asylum seekers receive the same higher standard of treatment in any Member State in which they choose to make their application, and to address criticism that the Directives are incompatible with human rights obligations. The UK asserts that its asylum procedures satisfy the standards imposed by its obligations under international and European law, and does not view further harmonization of asylum matters at EU level as necessary or appropriate. Its decision not to opt-in raises issues regarding sovereignty, subsidiarity, the rule of law and European integration. This article will explore these issues, as well as provide an overview of select provisions from the proposals in light of UK asylum policy.
Family of piecewise expanding maps having singular measure as a limit of ACIMs
Authors: LI ZHENYANG , GÓRA PAWEŁ , BOYARSKY ABRAHAM , PROPPE HARALD , ESLAMI PEYMAN
Published: November 2011

Keller [Stochastic stability in some chaotic dynamical systems. Monatsh. Math.94(4) (1982), 313–333] introduced families of W-shaped maps that can have a great variety of behaviors. As a family approaches a limit W map, he observed behavior that was either described by a probability density function (PDF) or by a singular point measure. Based on this, Keller conjectured that instability of the absolutely continuous invariant measure (ACIM) can result only from the existence of small invariant neighborhoods of the fixed critical point of the limit map. In this paper, we show that the conjecture is not true. We construct a very simple family of W-maps with ACIMs supported on the whole interval, whose limiting dynamical behavior is captured by a singular measure. Key to the analysis is the use of a general formula for invariant densities of piecewise linear and expanding maps [P. Góra. Invariant densities for piecewise linear maps of interval. Ergod. Th. & Dynam. Sys. 29(5) (2009), 1549–1583].
UNAUTHORIZED HUMANITARIAN INTERVENTION
Authors: Stein Mark S.
Published: November 2011

In this essay, I offer a utilitarian perspective on humanitarian
intervention. There is no generally accepted precise definition of the term
‘humanitarian intervention’. I will provisionally, and roughly,
define humanitarian intervention as the use of force by a state, beyond its
own borders, that has as a purpose or an effect the protection of the human
rights of noncitizens or the reduction of the suffering of noncitizens.
Preliminary Evaluation of an Online Training Package in Cognitive Behaviour Therapy: Satisfaction Ratings and Impact on Knowledge and Confidence
Authors: Westbrook David , McManus Freda , Clark Gavin , Bennett-Levy James
Published: November 2011

Background: Online CBT training is in its infancy. The initial studies have varied program characteristics and trainee groups, but results appear promising. At this stage, there is a need to evaluate programs with different characteristics to determine which are useful, and which are not. Method: This paper reports a preliminary evaluation of an online CBT training package, OCTC Online, which is distinguished from other online programs by its particularly strong focus on video presentations by trainers, accompanying PowerPoint slides, and video demonstrations of key clinical techniques. Participants (N = 94) completed online rating scales and questionnaires assessing (a) their satisfaction with the training; (b) their self-rated knowledge and confidence about the topics discussed (pre- and post-training); and (c) a multiple choice questionnaire (MCQ) objective test of knowledge (also pre- and post-training). Results: Results showed that on average students were highly satisfied with the online training modules, their self-rated confidence increased significantly, and so did their scores on the MCQ. Conclusions: The study has significant limitations but nevertheless contributes to the growing body of evidence that online training may have a useful part to play in enhancing therapists’ knowledge of CBT theory and techniques, and their confidence in using the techniques.
Cryopreservation ofin vitro-grown shoot tips of strawberry by the vitrification method using aluminium cryo-plates
Authors: Yamamoto Shin-ichi , Fukui Kuniaki , Rafique Tariq , Khan Nayyar Iqbal , Castillo Martinez Carlos Roman , Sekizawa Kentaro , Matsumoto Toshikazu , Niino Takao
Published: November 2011

Cryopreservation using an aluminium cryo-plate was successfully applied toin vitro-grown strawberry (Fragaria × ananassaDuch.) shoot tips. The shoots were cold-hardened at 5°C for 3 weeks with an 8-h photoperiod. The shoot tips (1.5–2.0 mm × 0.5–1.0 mm) were dissected from the shoot and pre-cultured at 5°C for 2 d on Murashige and Skoog medium containing 2 M glycerol and 0.3 M sucrose. The pre-cultured shoot tips were placed on the aluminium cryo-plate containing ten wells embedded in alginate gel. Osmoprotection was performed by immersing the cryo-plates in a loading solution (2 M glycerol and 0.8 M sucrose) for 30 min at 25°C. Dehydration was performed by immersing the cryo-plates in plant vitrification solution 2 for 50 min at 25°C. Then, the cryo-plate with shoot tips was transferred into an uncapped cryotube that was held on a cryo-cane and directly immersed into liquid nitrogen (LN). After storage in LN, shoot tips attached to the cryo-plate were directly immersed into 2 ml of a 1 M sucrose solution for regeneration. Using this procedure, the average regrowth level of vitrified shoot tips of 15 strawberry cultivars reached 81%. This new method has many advantages and will facilitate the cryostorage of strawberry germplasm.
Unraveling dynamical controls on the North Pacific carbon sink
Authors: Ayers Jennifer M. , Lozier M. Susan
Published: November 2011

A broad swath across the North Pacific basin uptakes a disproportionately large amount of atmospheric CO2every year, with the region of most intense uptake located in the North Pacific transition zone, from ∼30°N to 40°N–45°N. Though a net carbon sink on a mean annual basis, the region varies seasonally between a strong sink in winter and a neutral to weak source in summer. Herein we use observational carbon data to investigate processes regulating air‐sea CO2 flux in this region on seasonal and annual timescales by quantifying the impacts of temperature, biology, and physics on seawater pCO2. Temperature effects dominate the pCO2 signal seasonally, yet support only a portion of the annual CO2 uptake in the region, via their impact on the solubility of CO2 in seawater. Instead, processes removing carbon from surface waters dominantly support the region's uptake of CO2 on annual timescales: the vertical export of organic carbon to depth, and the geostrophic advection of dissolved inorganic carbon laterally out of the region. We find the location of this carbon sink region, traditionally attributed to a combination of biological and temperature effects, to instead be driven by the steady geostrophic divergence of DIC at these latitudes.