bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybridization among Arctic white‐headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene
Authors: Sonsthagen Sarah A. , Chesser R. Terry , Bell Douglas A. , Dove Carla J.
Published: May 2012

We studied the influence of glacial oscillations on the genetic structure of seven species of white‐headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice‐free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (FST= 0.129), introns (ΦST= 0.185), and mtDNA control region (ΦST= 0.461), with among‐group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among‐group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger τ estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white‐headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species‐specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white‐headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed.
CCR7‐independent transport of skin antigens occurs in the dermis
Authors: Yoshino Miya , Okuyama Kazuki , Murata Akihiko , Tomura Michio , Hayashi Shin‐Ichi
Published: May 2012

Under homeostatic conditions, skin DCs migrate to regional LNs transporting self‐antigens (self‐Ags). The transport of self‐Ags is considered to be critical for maintaining peripheral tolerance. Although the chemokine receptor CCR7 potently induces the migration of skin DCs to regional LNs, Ccr7−/− (Ccr7‐KO) mice do not show skin auto‐immune diseases. To resolve this inconsistency, we examined Ccr7‐KO epidermis‐ or dermis‐hyperpigmented transgenic (Tg) mice, in which the transport of skin self‐Ags is traceable by melanin granules (MGs). Under CCR7‐deficient conditions, the transport of epidermal MGs to regional LNs was impaired at 7 weeks of age. However, epidermal MGs could be transported when they had accumulated in the dermis. Ccr7‐KO‐dermis‐pigmented Tg mice confirmed the presence of CCR7‐independent transport from the dermis. Compared with WT‐dermis‐pigmented Tg mice, the amount of transported melanin and number of MG‐laden CD11c+ cells were both approximately 40% of the WT levels, while the number of MG‐laden CD205+ or CD207+ cells decreased to about 10% in skin regional LNs of Ccr7‐KO‐dermis‐pigmented Tg mice. Cell sorting highlighted the involvement of CD11c+ cells in the CCR7‐independent transport. Here, we show that CCR7‐independent transport of skin self‐Ags occurs in the dermis. This system might contribute to the continuous transport of self‐Ags, and maintain peripheral tolerance.
Neutral Pentacoordinate Halogeno‐ and Pseudohalogenosilicon(IV) Complexes with a Tridentate Dianionic O,N,O or N,N,O Ligand: Synthesis and Structural Characterization in the Solid State and in Solution
Authors: Weiß Jörg , Theis Bastian , Metz Stefan , Burschka Christian , Fonseca Guerra Célia , Bickelhaupt F. Matthias , Tacke Reinhold
Published: May 2012

A series of neutral pentacoordinate silicon(IV) complexes with an SiFO2NC, SiBrO2NC, SiO2NC2, SiO2N2C, SiFON2C, SiBrON2C, SiON2C2, or SiON3C skeleton was synthesized and structurally characterized by multinuclear NMR spectroscopy in the solid state and in solution and by single‐crystal X‐ray diffraction. The compounds studied contain a tridentate dianionic O,N,O or N,N,O ligand, a phenyl ligand, and a (pseudo)halogeno ligand (F, Br, CN, N3, NCS). The structures, NMR spectroscopic parameters, and chemical properties of these silicon(IV) complexes were compared with those of related compounds that contain an analogous tridentate dianionic S,N,O ligand instead of the O,N,O or N,N,O ligand (comparison of S/O/NMe analogues). In addition, two cationic pentacoordinate silicon(IV) complexes with an SiO2N2C and SiON3C skeleton, respectively, were synthesized (isolated as iodides) and structurally characterized. These compounds contain a tridentate O,N,O or N,N,O ligand, a phenyl ligand, and an acetonitrile ligand. The experimental investigations reported in this article were complemented by computational studies to better understand the different properties of some of the S/O/NMe analogues studied.
Recyclable Hybrid Silica‐Based Catalysts Derived from Pd–NHC Complexes for Suzuki, Heck and Sonogashira Reactions
Authors: Borja Guadalupe , Monge‐Marcet Amàlia , Pleixats Roser , Parella Teodor , Cattoën Xavier , Wong Chi Man Michel
Published: May 2012

Two silylated Pd–NHC complexes were immobilized on hybrid silicas by sol‐gel cocondensation with tetraethyl orthosilicate (TEOS) and performed well as recyclable catalysts towards the Heck, Suzuki, and Sonogashira coupling reactions. Remarkable conversion and recyclability were achieved in the Suzuki reaction with a challenging aryl chloride. No side products and no undesired homocoupling were observed in Suzuki or Heck reactions, which facilitates the final purification step for the cross‐coupling products. High turnover numbers and turnover frequencies were found for copper‐ and phosphane‐free Sonogashira reaction between p‐bromoacetophenone and phenylacetylene.
Mineral substances and macronutrients in the anaerobic conversion of biomass: An impact evaluation
Authors: Vintiloiu Anca , Lemmer Andreas , Oechsner Hans , Jungbluth Thomas
Published: May 2012

Optimal nutrient supply in the digester is essential for efficient biogas production. The aim of this study was to analyze the effects of various micro‐ and macronutrients on the process stability by a field test. The digestates of 25 biogas plants across the federal state of Baden‐Württemberg, Germany, were investigated. Collected data including trace elements, macronutrients, and volatile fatty acids (VFA) concentrations, as well as the organic loading rate and hydraulic retention time were subjected to statistical analysis. High variations in the concentrations within the different biogas plants were observed. Statistically significant effects of substrate constituents and process parameters on the stability of the anaerobic digestion process were found. Several micro‐ and macronutrients and the relationships between these elements, as well as the process parameters propionic acid, acetic acid, and acetic acid equivalent were tested. Ni, Mo, and S had a consistent statistically significant effect, while the organic loading rate and Se only showed an effect limited to the acetic acid concentration and the acetic acid equivalent. No statistically significant effect could be shown for Fe, Co, and Na. Most of the significant interactions between the tested elements contained Ni, Fe, and Co. This shows that a balanced relation between the concentrations of these elements is of greater importance than the presence of individual elements for a digester to be able to operate at high organic loading rates and maintain low VFA concentrations.
Proliferating primary hepatocytes from the pUR288 lacZ plasmid mouse are valuable tools for genotoxicity assessment in vitro
Authors: Zwart Edwin P. , Schaap Mirjam M. , van den Dungen Myrthe W. , Braakhuis Hedwig M. , White Paul A. , Steeg Harry van , Benthem Jan van , Luijten Mirjam
Published: May 2012

Safety assessments of substances with regard to genotoxicity are generally based on a combination of in vitro and in vivo tests. These tests are performed according to a (tiered) test strategy whereby a positive result in vitro usually triggers further testing in vivo. A low specificity and high frequency of irrelevant positive results associated with most in vitro mammalian cell genotoxicity assays necessitates the design and validation of suitable alternatives. As such, we examined the feasibility of culturing primary hepatocytes from the pUR288 lacZ reporter mouse, and moreover, using established cultures to reliably assess genotoxic activity in vitro. Initial studies characterizing the metabolic capacity of proliferating lacZ primary hepatocytes indicated that these cells retained at least some activities important for xenobiotic metabolism: cytochrome P450 1A1 enzyme activities were markedly increased in the hepatocytes after exposure to benzo[a]pyrene, and also UDP‐glucuronosyl transferase and glutathione‐S‐transferase activities, both Phase II enzymes, were detected. Increasing levels of phosphorylated p53 at residue serine 389 after ultraviolet treatment indicated a properly functioning p53, one of the criteria for an effective new test system. Four genotoxic substances with different mechanisms of genotoxicity, i.e., benzo[a]pyrene, bleomycin, etoposide, and cyclophosphamide, were tested in the lacZ rescue assay. For etoposide and cyclophosphamide, the induction of mutant colonies was rather low. Exposure to benzo[a]pyrene and bleomycin, however, yielded a clear concentration‐dependent induction of the lacZ mutant frequency. Based on our preliminary observations, proliferating lacZ primary hepatocytes are a promising new tool for the assessment of genotoxic hazard. Environ. Mol. Mutagen. 2012. © 2012Wiley Periodicals, Inc.
Vertical distribution of pharmaceuticals in lake sediments—citalopram as potential chemomarker
Authors: Lahti Marja , Oikari Aimo
Published: May 2012

The use of pharmaceuticals has increased enormously over the last few decades and serious concerns about their environmental fate and effects have arisen. Thus far, there is little knowledge about the historical pollution of the environment by pharmaceuticals. In the present study, sediment columns from three lake sites adjacent to wastewater treatment plants were collected, further divided in 2- or 2.5-cm slices, and analyzed for 15 pharmaceuticals by liquid chromatography-tandem mass spectrometry. In addition, sediment columns were historically interpreted by analyzing fecal sterols (coprostanol and cholesterol) as well as organic material and organic carbon. Several pharmaceuticals were detected in sediments, the most abundant being citalopram, bisoprolol, and propranolol. At site A, pharmaceuticals prevailed only in the uppermost 15 cm, whereas at site B they existed in the whole sediment column (0–30 cm). Pharmaceuticals were not found in site C sediments. Based on the sterol analyses, municipal wastewater contamination at sites A, B, and C was found in the uppermost 15, 30, and 20 cm, respectively. For the first time, contamination of sediments by pharmaceuticals was demonstrated below the subsurface (up to a depth of 30 cm). When considering the consumption and the observed concentration profiles of pharmaceuticals, a clear increasing trend of citalopram toward the surface was evident at site A. Environ. Toxicol. Chem. 2012; 31: 1738–1744. © 2012 SETAC
Geoarchaeology and Paleoenvironmental Context of the Burntwood Creek Rockshelter, High Plains of Northwestern Kansas, U.S.A
Authors: Murphy Laura R. , Mandel Rolfe D.
Published: May 2012

The first systematic geoarchaeological study of a rockshelter in Kansas yielded information about rockshelter formation, Holocene paleoenvironments, archaeological site formation processes, and prehistoric human habitation and site use. The rockshelter was carved by groundwater sapping; colluvium, alluvium, and roof‐fall debris subsequently accumulated on its floor. An assemblage of Late Archaic (∼2000–4000 14C years before present [yr B.P.]) cultural deposits (lithic material, bone, and charcoal) is preserved in a 2‐m thick package of colluvium and alluvium in front of the shelter. Chipped stone analysis indicates that Late Archaic occupants of the shelter were using mostly local materials and resharpening their stone tools at the shelter. Stable carbon isotope and phytolith analyses indicate that a mixed C3 and C4 plant community existed in the study area and that it changed in composition through the late Holocene. Based on the phytolith assemblage from an unlined fire pit at the front of the shelter, Late Archaic people used local hackberry trees for fuel and/or food.
How to identify leadership potential: Development and testing of a consensus model
Authors: Dries Nicky , Pepermans Roland
Published: May 2012

Building on two studies, the current article responds to urgent calls in the literature for more empirical research on how to identify leadership potential. Based on an extensive review of the 1986–2010 literature, and applying a combination of qualitative and quantitative techniques, we developed a model of leadership potential consisting of four quadrants: Analytical skills (containing the factors Intellectual curiosity, Strategic insight, Decision making, and Problem solving); Learning agility (containing the factors Willingness to learn, Emotional intelligence, and Adaptability); Drive (containing the factors Results orientation, Perseverance, and Dedication); and Emergent leadership (containing the factors Motivation to lead, Self‐promotion, and Stakeholder sensitivity). Notably, the developed model steers clear from some of the typical issues that tend to hinder valid assessments of leadership potential (i.e., the confound between performance and potential, as well as that between leadership potential and successful, mature leadership). Furthermore, high consensus was found between top managers, line managers, and HR managers about the practical relevance of the proposed model. The article concludes with some specific future avenues for research and practice. © 2012 Wiley Periodicals, Inc.
The role of leadership in successful international mergers and acquisitions: Why Renault‐Nissan succeeded and DaimlerChrysler‐Mitsubishi failed
Authors: Gill Carol
Published: May 2012

This article compares and contrasts the Renault‐Nissan and DaimlerChrysler‐Mitsubishi mergers to consider the relative and combined effects of national and organizational culture on the performance of Nissan and Mitsubishi. It also examines the reasons why the Renault‐Nissan merger was successful and the DaimlerChrysler‐Mitsubishi merger failed. It finds that Japanese national culture influenced organizational culture and HRM practices, which created organizations that had no sense of urgency, profit orientation, or accountability and led to poor market and financial performance. It also finds that leadership was a major factor impacting on the success of the turnaround efforts of these two organizations. These findings have implications for leaders and human resource management practitioners engaged in international business and are of particular relevance to Western organizations working with organizations in high‐context countries with a collectivist rather than individualist orientation. © 2012 Wiley Periodicals, Inc.
Macronutrient intake and risk of urothelial cell carcinoma in the European prospective investigation into cancer and nutrition
Authors: Allen Naomi E. , Appleby Paul N. , Key Timothy J. , Bueno‐de‐Mesquita H.B. , Ros Martine M. , Kiemeney Lambertus A.L.M. , Tjønneland Anne , Roswall Nina , Overvad Kim , Weikert Steffen , Boeing Heiner , Chang‐Claude Jenny , Teucher Birgit , Panico Salvatore , Sacerdote Carlotta , Tumino Rosario , Palli Domenico , Sieri Sabina , Peeters Petra , Quirós Jose Ramón , Jakszyn Paula , Molina‐Montes Esther , Chirlaque María‐Dolores , Ardanaz Eva , Dorronsoro Miren , Khaw Kay‐Tee , Wareham Nick , Ljungberg Börje , Hallmans Göran , Ehrnström Roy , Ericson Ulrika , Gram Inger Torhild , Parr Christine L. , Trichopoulou Antonia , Karapetyan Tina , Dilis Vardis , Clavel‐Chapelon Françoise , Boutron‐Ruault Marie‐Christine , Fagherrazzi Guy , Romieu Isabelle , Gunter Marc J. , Riboli Elio
Published: May 2012

Previous studies have suggested that dietary factors may be important in the development of bladder cancer. We examined macronutrient intake in relation to risk of urothelial cell carcinoma among 469,339 men and women in the European Prospective Investigation into Cancer and Nutrition. Associations were examined using Cox regression, stratified by sex, age at recruitment and centre and further adjusted for smoking status and duration, body mass index and total energy intake. After an average of 11.3 years of follow‐up, 1,416 new cases of urothelial cell carcinoma were identified. After allowing for measurement error, a 3% increase in the consumption of energy intake from animal protein was associated with a 15% higher risk (95% confidence interval [CI]: 3–30%; ptrend = 0.01) and a 2% increase in energy from plant protein intake was associated with a 23% lower risk (95% CI: 36–7%, ptrend = 0.006). Dietary intake of fat, carbohydrate, fibre or calcium was not associated with risk. These findings suggest that animal and/or plant protein may affect the risk of urothelial cell carcinoma, and examination of these associations in other studies is needed.
A Cultural and Social Cognitive Model of Differences in Acculturation Orientations, Alcohol Expectancies, and Alcohol‐Related Risk Behaviors Among Hispanic College Students
Authors: Des Rosiers Sabrina E. , Schwartz Seth J. , Zamboanga Byron L. , Ham Lindsay S. , Huang Shi
Published: May 2012

Objectives

The present study used a cultural and social cognitive conceptual framework to investigate whether alcohol expectancies and valuations would mediate the associations between specific acculturation orientations and alcohol‐related risk behaviors.

Design

The sample comprised 1,527 Hispanic students attending colleges and universities in diverse regions of the United States. Respondents completed self‐report measures of Hispanic and American cultural practices; alcohol expectancies and valuations; and self‐reported frequency of hazardous alcohol use, binge drinking, sexual activity under the influence of alcohol, driving under the influence of alcohol, and riding with a drunk driver. Latent class analysis was used to classify participants into acculturation orientations.

Results

Results indicated that acculturation orientations were differentially associated with alcohol‐related risk outcomes, with separated bicultural and low bicultural orientations inversely related to all of the alcohol‐related risk behaviors except for riding with a drunk driver. Negative expectancy valuations were positively associated with endorsement of binge drinking and drunk driving and negative expectancies were negatively associated with binge drinking, drunk driving, and riding with a drunk driver. With the exception of sexual activity under the influence of alcohol, the associations between acculturation orientations and alcohol‐related risk behaviors were partially mediated by positive alcohol expectancies.

Conclusions

Our findings provided relevant data that are informative for preventing alcohol and related risk behaviors among Hispanic college students.
Rodlet cells development in the intestine of sea bass (Dicentrarchus labrax)
Authors: Laurà Rosaria , Germanà Germana P. , Levanti Maria B. , Guerrera Maria C. , Radaelli Giuseppe , de Carlos Felix , Suárez Alberto Álvarez , Ciriaco Emilia , Germanà Antonino
Published: May 2012

The enigmatic rodlet cells (RCs) are characterized by conspicuous inclusions named “rodlets”. They were discovered over 100 years ago and were considered as parasites but shortly afterward interpreted as endogenous cells. The RCs have been described in different tissues of marine and freshwater teleosts, but their origin and function remain unknown. This work was designed to an ultrastructural study on RCs development and distribution in intestinal epithelium of Dicentrarchus labrax. Three different stages of RCs development from early precursor cells to mature phase were observed, as well as a migration and finally an extrusion of their contents. In this study, the immature cells were found near the basal epithelium membrane. They were mainly identified by a rough endoplasmic reticulum with dilated cisternae, by developing rodlets and a thin fibrillar coat. The maturing RCs, localized in the middle zone of the epithelium, appeared to be undergoing a reorganization of the cell organelles. The mature RCs, placed near the free surface, showed a thick subplasmalemmar fibrillar coat. Most of the organelles were aggregated at the cell apex with a basally located nucleus. A cellular polarity was more evident. One of the most conspicuous features was the occurrence of mature rodlets club‐sac in shape orientated toward the cell apex. Adhesive junctions between surface epithelial cells and RCs, while discharging their contents, were seen. We have connected morphological figures and distribution to different stages of development in RCs, supporting the hypothesis of their secretory function. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Interstitial fluid pressure as an alternate regulator of angiogenesis independent of hypoxia driven HIF‐1α in solid tumors
Authors: Aung Khin Zarchi , Pereira Barry P. , Tan Pamela H.S. , Han Hwan‐Chour , Nathan Saminathan S.
Published: May 2012

We previously showed that interstitial fluid pressure (IFP) may be an alternate regulator of angiogenesis in solid tumors. Given the accepted link between hypoxia‐induced factor and angiogenesis this study investigated the effect of IFP on hypoxia‐inducible factor (HIF‐1α) and vascular endothelial growth factor (VEGF) in human osteosarcoma xenografts in SCID mice and in different hypoxic environments. Tumors were grown either at heterotopic (flank) or orthotopic (medullary canal of the proximal tibia) sites in the host animal. Microfluidic probes determined pH, O2‐saturation, IFP, and peripheral blood flow perfusion continuously. We assessed tumor growth in the orthotopic site (n = 15) by softex radiographs weekly, 3D microCT, histological evaluation, and for molecular responses. An increased cytoplasmic immunohistostaining of cells for HIF‐1α (p = 0.03) and VEGF‐A (p = 0.004) on the outer periphery was noted compared to the tumor center, with VEGFR2 uniformly stained throughout. This paralleled a raised state of interstitial hypertension (p = 0.007) in the tumor center relative to the peripheral surface but was inconsistent with a state of hypoxia (p = 0.03) in the tumor center. In vitro culture of human osteosarcoma cell lines (HOS, U2OS) and a human osteoblast control at 0‐ and 20‐mmHg of hydrostatic pressure revealed suppression of HIF‐1α (p = 0.02) and VEGF‐A (p = 0.02) gene expression when IFP was raised, while the effect on VEGFR1 was equivocal. This study proposes an alternative regulatory angiogenic pathway via the influence of IFP on cancer cell function. The identification of a mechanistic cellular link to the physical parameter becomes an important tool to evaluate cancer cell growth within solid tumors. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:2038–2045, 2012
Residue Stabilization in the Fire Retardancy of Wood–Plastic Composites: Combination of Ammonium Polyphosphate, Expandable Graphite, and Red Phosphorus
Authors: Seefeldt Henrik , Braun Ulrike , Wagner Manfred H.
Published: May 2012

Combinations of different common flame retardants in wood–plastic composites (WPCs) are tested to identify synergistic or antagonistic effects with the goal of improving the fire performance of WPCs. Flame retardants investigated are expandable graphite (EG), ammonium polyphosphate (APP), and red phosphorus (RP) and combinations of two of them are used. The fire behavior is studied by cone calorimetric measurements. Additional thermogravimetry is used for further investigations. The fire tests show that EG has the highest potential for flame retardancy, but due to its expansion it cracks the formed residue layer. Combinations of EG with RP or with high amounts of APP are able to suppress this cracking.
The influence of hot‐chamber die casting parameters on the microstructure and mechanical properties of magnesium‐aluminum alloys containing alkaline elements
Authors: Rzychoń T. , Adamczk‐Cieślak B. , Kiełbus A. , Mizera J.
Published: May 2012

The AJ62 magnesium alloy (Mg‐6Al‐2Sr) is characterized by good creep resistance up to 175°C and good castability enabling production of thin‐walled elements in die casting process. The aim of the work was to analyse the influence of hot‐chamber die casting parameters on the microstructure and mechanical properties of the AJ62 magnesium alloy. Die casting of investigated alloys was carried out on a 280 tone locking force hot‐chamber die casting machine. The piston speed, pressure, die temperature and casting temperature were changed during die casting. The microstructural examinations after die casting showed that the alloy consisted of the solid solution a, lamellar eutectic (Al, Mg)4Sr, minor amounts of massive Al3Mg13Sr phase and globular particles of Mn5Al8. Precipitates of Mg17Al12 phase were not detected. The stereological examinations after die casting showed that the volume fraction of massive Al3Mg13Sr phase was dependant on the casting rate. Changing the casting rate had an influence on the volume fraction of (Al, Mg)4Sr and Al3Mg13Sr phases. The gas porosity is strongly influenced by the applied pressure and the plunger velocity during die casting process. The mechanical properties of AJ62 magnesium alloy are better at low porosity and high volume fraction of (Al, Mg)4Sr phase.
Periodic approximations of homogenization problems
Authors: Pankov Alexander
Published: May 2012

We show that any non‐periodic nonlinear elliptic homogenization problem can be approximated by periodic homogenization problems. Copyright © 2012 John Wiley & Sons, Ltd.
A method for proteomic analysis of equine subchondral bone and epiphyseal cartilage
Authors: Desjardin Clémence , Balliau Thierry , Valot Benoît , Zivy Michel , Wimel Laurence , Guérin Gérard , Cribiu Edmond , Schibler Laurent
Published: May 2012

Proteomic analyses of cartilage and, to a lesser extent, of bone have long been impaired because of technical challenges related to their structure and biochemical properties. We have developed a unified method based on phenol extraction, 2DE, silver staining, and subsequent LC‐MS/MS. This method proved to be efficient to characterize the proteome of equine cartilage and bone samples collected in vivo. Since proteins from several cellular compartments could be recovered, our procedure is mainly suitable for in situ molecular physiology studies focused on the cellular content of chondrocytes, osteoblasts, and osteoclasts as well as that of the extracellular matrix, with the exception of proteoglycans. Our method alleviates some drawbacks of cell culture that can mask physiological differences, as well as reduced reproducibility due to fractionation. Proteomic comparative studies between cartilage and bone samples from healthy and affected animals were thus achieved successfully. This achievement will contribute to increasing knowledge on the molecular mechanisms underlying the physiopathology of numerous osteoarticular diseases in horses and in humans.
Identification and characterization of highly expressed proteins in sperm cells of the marine mussel Mytilus edulis
Authors: Diz Angel P. , Dudley Edward , Skibinski David O. F.
Published: May 2012

Proteomic analysis on sperm has been restricted to only a few model organisms. We present here a 2DE PAGE proteome map of sperm cells from a nonmodel organism, the marine mussel Mytilus edulis, a free‐spawning marine invertebrate with external fertilization. Ninety‐six protein spots showing high expression were selected and of these 77 were successfully identified by nESI–MS analysis. Many of the identifications are relevant to sperm cell physiology and mtDNA functioning. The results and proteomics approach used are discussed in relation to their potential for advancing understanding of the unusual system of mtDNA inheritance described in Mytilus spp., and for the testing of evolutionary hypotheses pertaining to the role of fertilization in the speciation process.
Investigation of catalyst‐transfer condensation polymerization for the synthesis of n‐type π‐conjugated polymer, poly(2‐dioxaalkylpyridine‐3,6‐diyl)
Authors: Nanashima Yutaka , Shibata Rena , Miyakoshi Ryo , Yokoyama Akihiro , Yokozawa Tsutomu
Published: May 2012

Kumada‐Tamao coupling polymerization of 6‐bromo‐3‐chloromagnesio‐2‐(3‐(2‐methoxyethoxy)propyl)pyridine 1 with a Ni catalyst and Suzuki‐Miyaura coupling polymerization of boronic ester monomer 2, which has the same substituted pyridine structure, with tBu3PPd(o‐tolyl)Br were investigated for the synthesis of a well‐defined n‐type π‐conjugated polymer. We first carried out a model reaction of 2,5‐dibromopyridine with 0.5 equivalent of phenylmagnesium chloride in the presence of Ni(dppp)Cl2 and then observed exclusive formation of 2,5‐diphenylpyridine, indicating that successive coupling reaction took place via intramolecular transfer of Ni(0) catalyst on the pyridine ring. Then, we examined the Kumada‐Tamao polymerization of 1 and found that it proceeded homogeneously to afford soluble, regioregular head‐to‐tail poly(pyridine‐2,5‐diyl), poly(3‐(2‐(2‐(methoxyethoxy)propyl)pyridine) (PMEPPy). However, the molecular weight distribution of the polymers obtained with several Ni and Pd catalysts was very broad, and the matrix‐assisted laser desorption ionization time‐of‐flight mass spectra showed that the polymer had Br/Br and Br/H end groups, implying that the catalyst‐transfer polymerization is accompanied with disproportionation. Suzuki‐Miyaura polymerization of 2 with tBu3PPd(o‐tolyl)Br also afforded PMEPPy with a broad molecular weight distribution, and the tolyl/tolyl‐ended polymer was a major product, again indicating the occurrence of disproportionation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Deprotonation reaction of α‐amino acid N‐carboxyanhydride at 4‐CH position by yttrium tris[bis(trimethylsilyl)amide]
Authors: Ling Jun , Peng Hui , Shen Zhiquan
Published: May 2012

Reaction of yttrium tris[bis(trimethylsilyl)amide] [(TMSN)3Y] with equivalent L‐alanine N‐carboxyanhydride (ALA NCA) yields yttrium α‐isocyanato carboxylate (II), yttrium ketenyl carbamate (III), and hexamethyldisilazane (V). The products indicate that 4‐CH group of ALA NCA monomer is deprotonated in addition to 3‐NH group, which has been neglected in NCA chemistry for decades. This result proves the acidity of 4‐CH in NCA and provides the first direct evidence for racemization phenomenon of NCA in strong base in microscopic aspect. Rare earth tris[bis(trimethylsilyl)amide] (TMSN)3Ln (Ln = Sc, Y, La, Dy, and Lu) compounds are high efficient catalysts for ring‐opening polymerizations of NCAs. Polypeptides can be produced in quantitative yields with narrow molecular weight distributions below 1.3, and block copolypeptides can be facilely prepared by sequential addition method. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Metal‐ and solvent‐free, clickable synthesis and postpolymerization functionalization of poly(triazole)s
Authors: Deng Fengyang , Xu Bin , Gao Yong , Liu Zheng , Yang Duanguang , Li Huaming
Published: May 2012

In this study, a series of linear poly(triazole)s (PTAs) were successfully synthesized by the metal‐ and solvent‐free, thermal click polymerization of diazide and dialkyne (A2 + B2) monomers. All click polymerizations proceeded smoothly at 80 °C in an open atmosphere without protection from oxygen and moisture. After being polymerized for 36 h, the crude polymer was further fractionated into three fractions using a multistep precipitation method. By selectively choosing precipitating agents, this process produced poly(triazole) fractions with low polydispersity index (<1.30). The resulting PTAs are soluble in common organic solvents and stable at a temperature up to 320 °C. Furthermore, the methyl benzoate moieties in the main chain can serve as useful building blocks for further postpolymerization functionalization, yielding 1,2,4‐triazole derivatives. This functionalization strategy offers potential for the development of novel triazole‐based materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synchrotron radiation X‐ray topography and X‐ray diffraction of homoepitaxial GaN grown on ammonothermal GaN
Authors: Sintonen Sakari , Ali Muhammad , Suihkonen Sami , Kostamo Pasi , Svensk Olli , Sopanen Markku , Lipsanen Harri , Paulmann Carsten , Tuomi Turkka O. , Zajac Marcin
Published: May 2012

In this study, homoepitaxial GaN grown on ammonothermal GaN substrates is non‐destructively investigated by synchrotron radiation X‐ray topography (SR‐XRT) and X‐ray diffraction (XRD). The homoepitaxial GaN layer was found to be of excellent crystal quality with individual dislocations clearly visible in the SR‐XRT images. SR‐XRT images and XRD rocking curves suggest the dislocations are mainly of mixed type. To the best of our knowledge the measured dislocation density is the lowest reported in a homoepitaxial GaN film (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and applications of orientation‐patterned gallium arsenide for mid‐infrared generation
Authors: Grisard A. , Gutty F. , Lallier E. , Gérard B. , Jimenez J.
Published: May 2012

Nonlinear optical materials play a key role in the development of coherent sources of radiation, by frequency conversion of light from other light sources, e.g. diode, solid‐state, and fiber lasers, into spectral ranges where few lasers exist or perform poorly. Based on the principle of the quasi‐phase matching, the design and fabrication of orientation‐patterned Gallium Arsenide crystals (OP‐GaAs) has recently led to demonstrations of second harmonic generation, optical parametric generation, amplification and oscillation from 1 to 12 µm. The most efficient fabrication route for these crystals relies on the use of the near‐equilibrium growth process HVPE (Hydride Vapour Phase Epitaxy), by orientation‐selective regrowth on OP‐GaAs template wafers with a thickness suited to bulk nonlinear optics. This work deals with recent characterizations based on optical experiments and cathodoluminescence measurements, targeting the identification of the main defects, their spatial distribution, and their relation to the optical propagation losses. Latest improvements of the HVPE growth step have enabled to reach an unprecedented level of losses, below 0.016 cm‐1, and a large range of available QPM periods and thickness of structures (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Xanthorrhizol Induces Apoptosis Through ROS‐Mediated MAPK Activation in Human Oral Squamous Cell Carcinoma Cells and Inhibits DMBA‐Induced Oral Carcinogenesis in Hamsters
Authors: Kim Ju Yeon , An Jeong Mi , Chung Won‐Yoon , Park Kwang‐Kyun , Hwang Jae Kwan , Kim Du Sik , Seo Su Ryeon , Seo Jeong Taeg
Published: May 2012

Xanthorrhizol, a natural sesquiterpenoid compound isolated from Curcuma xanthorrhiza Roxb, has been known to inhibit the growth of human colon, breast, liver and cervical cancer cells. In this study, xanthorrhizol decreased cell viability, induced apoptosis and decreased the level of full‐length PARP in SCC‐15 oral squamous cell carcinoma (OSCC) cells. A decrease in cell viability and PARP degradation was not prevented by treatment with the caspase inhibitor Z‐VAD‐fmk in xanthorrhizol‐treated cells. Xanthorrhizol treatment elevated intracellular Ca2+ and ROS levels in SCC‐15 cells. Treatment with a Ca2+ chelator, EGTA/AM, did not affect xanthorrhizol‐ induced cytotoxicity, but cell viability was partly recovered by treatment with endogenous antioxidant, GSH, or hydroxy radical trapper, MCI‐186. Furthermore, the viability of xanthorrhizol‐treated SCC‐15 cells was significantly restored by treatment with SB203580 and/or SP600125 but not significantly by PD98059 treatment. Xanthorrhizol‐induced activation of p38 MAPK and JNK was blocked by MCI‐186. Finally, xanthorrhizol suppressed the number of tumors in buccal pouches and increased the survival rate in hamsters treated with 7,12‐dimethylbenz[a]anthracene. In conclusion, xanthorrhizol may induce caspase‐independent apoptosis through ROS‐mediated p38 MAPK and JNK activation in SCC‐15 OSCC cells and prevent chemical‐induced oral carcinogenesis. Therefore, xanthorrhizol seems to be a promising chemopreventive agent. Copyright © 2012 John Wiley & Sons, Ltd.
Experimentelle und numerische Untersuchungen zu geklebten Glas‐Stahlverbindungen
Authors: Menkenhagen Jochen , Koschecknick Kai
Published: May 2012

Der vorliegende Fachbeitrag befasst sich mit der Betrachtung numerischer Untersuchungen geklebter Glas‐Stahlverbindungen zur Entwicklung von Nachweiskonzepten für neuartige Glasfassadenkonstruktionen, die in der modernen Architektur in zunehmendem Maße eingesetzt werden. Das Erforschen der Materialeigenschaften geeigneter Klebstoffe und das Implementieren dieser Eigenschaften in ein FE‐Programm sind zentrales Thema des Artikels.
Optimierung zukunftsfähiger Gebäudehüllen
Authors: Heusler Winfried
Published: May 2012

Zukunftsfähige Gebäudehüllen sparen Energie und gewinnen Energie aus Sonnenstrahlung. Ihnen liegen materialeffiziente Konzepte und Komponenten zugrunde. In Zeiten sich wandelnder Anforderungen und Möglichkeiten entscheiden über die Zukunftsfähigkeit die Effizienz der Planungs‐, Bau‐ und Betriebsprozesse sowie die Modernisierungsfähigkeit der Gebäudehülle. Letztendlich sollte bei Optimierungsmaßnahmen die ökologische, ökonomische und soziokulturelle Bilanz von Nutzen und Aufwand in der Planung sowie beim Bau, Betrieb und Abbruch des Gebäudes positiv ausfallen. Als hilfreich erweist sich diesbezüglich eine die Qualität sichernde und den Aufwand begrenzende Systemtechnik für die Komponenten der Gebäudehülle, mit optimierten Schnittstellen zu den angrenzenden Gewerken. Große Vorteile bietet im gesamten Lebenszyklus die Modulbauweise. Bei der Planung zukunftsfähiger Gebäudehüllen müssen jedoch neben organisatorischen und technischen Maßnahmen zur Minimierung von Verschwendung auch gestalterische Aspekte Berücksichtigung finden.
Die Closed‐Cavity‐Fassade
Authors: Lutz Martin
Published: May 2012

Die energetische Nachhaltigkeit eines Gebäudes wird maßgeblich vom ingenieurtechnischen Zusammenwirken von Fassade und Raumkonditionierung bestimmt. Mit einer “intelligenten“ Fassade, der Closed‐Cavity‐Fassade, die alle physikalischen, energie‐ und tageslichttechnischen Aspekte wirklich löst, lässt sich ein nachhaltiges und somit zukunftsfähiges Planungsziel erreichen. Der Gebäudehülle kommt unter Berücksichtigung der EnEV 2009 und vor allem mit Blick auf die voraussichtlich nochmals um etwa 25 % verschärfte EnEV 2012 eine noch bedeutendere Rolle zu. Die derzeit in der Vermarktung nahezu unverzichtbaren Green‐Building‐Zertifizierungslabels DGNB, LEED, BREEAM usw., stärken diese Schlüsselrolle zusätzlich.
Cabot Circus, Bristol Ebene Vierecknetze für freigeformte Glasdächer
Authors: Schober Hans , Justiz Stefan
Published: May 2012

Im Rahmen der Neugestaltung des Stadteilzentrums Bristol Broadmead wurden ein bestehendes Kaufhaus, ein Freizeitzentrum und verschiedene Einzelhandelsgeschäfte über Glasdächer miteinander verbunden. Die kuppelartige Form des Hauptdaches besteht aus einer einlagigen, doppelt gekrümmten Gitterschale. Einlagige, doppelt gekrümmte Gitterschalen bilden auch die Dächer über den Straßen und entsprechen hier in ihrer Funktionsweise einem Tonnendach. Sie werden nur an ihren zwei Längskanten gestützt. Die Herausforderungen in Formfindung, Berechnung und Bemessung einer großen Netzkuppel sollen in diesem Beitrag anhand des Beispiels besprochen werden.
Großflächiger Einsatz von entspiegelten Gläsern – Ein Erfahrungsbericht
Authors: Ludwig Josef J.
Published: May 2012

Entspiegelte Gläser sind seit geraumer Zeit zum Beispiel im Displaybereich oder großflächiger im Vitrinenbau im Einsatz. Um wirklich maximale Transparenz an einer Fassade verwirklichen zu können, sind diese Gläser die logische Konsequenz. Am Beispiel einer Seilnetzfassade am Bauvorhaben Financial Center in Abu Dhabi soll aufgezeigt werden, mit welchen Aufgabenstellungen und Herausforderungen man konfrontiert ist, wenn 10.000 qm «Museumsglas» eingebaut werden.
Shanghai Oriental Sport Center – SOSC
Authors: Plieninger Sven , Chen Wei
Published: May 2012

The following paper is based on a lecture, hold by Magdalene Weiss (gmp von Gerkan, Marg und partner) and Sven Plieninger (schlaich bergermann und partner) at Tongji University Shanghai on 30th November 2011.
Prospects and challenges for an archaeology of global climate change
Authors: Hudson Mark J. , Aoyama Mami , Hoover Kara C. , Uchiyama Junzō
Published: May 2012

Archaeology has a long history of research in reconstructing past environments and in attempting to understand the interactions between climate and human societies. So far, however, there has been little attempt by archaeologists to employ this knowledge in the debate over current global climate change. This paper provides a broad overview of the relevance of archaeology to the problem of global climate change, yet also attempts to consider some of the challenges that require further debate. We propose five areas where archaeology may be able to make significant contributions to global climate change discourse: (1) the study not just of past social ‘collapse’ but of how ancient societies attempted to manage decline and recovery in the face of long‐term environmental change; (2) the ability to rethink the nature/culture divide; (3) the use of public archaeology to further education and awareness on environmental links and impacts; (4) the study of social injustice and how it may affect societal responses to the environment; and (5) the building of common ‘intercultural’ responses to climate change. Challenges identified are (1) making clearer in public debate the relevance of archaeology to present and future climate change; (2) the contexts in which people really learn from the past; (3) how different (national) traditions of archaeological research may affect our ability to relate archaeology to global climate change; and (4) how human‐induced climate change on a global scale alters traditional historical approaches to human agency.WIREs Clim Change2012 doi: 10.1002/wcc.174

This article is categorized under:

Climate, History, Society, Culture > Disciplinary Perspectives
Bayesian estimation for target tracking: part II, the Gaussian sigma‐point Kalman filters
Authors: Haug A.J.
Published: May 2012

This is the second part of a three part article examining methods for Bayesian estimation and tracking. In the first part we presented the general theory of Bayesian estimation where we showed that Bayesian estimation methods can be divided into two very general classes: a class where the observation conditioned posteriordensitiesare propagated in time through a predictor/corrector method; and a second class where the first twomomentsare propagated in time, with state and observation moment prediction steps followed by state moment update steps that use the latest observations. In this second part, we make the assumption that all densities are Gaussian and, after applying an affine transformation and approximating all nonlinear functions by interpolating polynomials, we recover the sigma‐point class of Kalman filters, including the unscented, spherical simplex, and Gauss‐Hermite Kalman filters. In part 3, we will show that approximating a density by a set of Monte Carlo samples leads to particle filter methods, where the posterior density is propagated in time and moment integrals are approximated by sample moments.WIREs Comput Stat2012 doi: 10.1002/wics.1215

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Bayesian Methods and Theory
Educational Assortative Mating and Income Inequality in Denmark
Authors: Breen Richard , Andersen Signe Hald
Published: May 2012

Many writers have expressed a concern that growing educational assortative mating will lead to greater inequality between households in their earnings or income. In this article, we examine the relationship between educational assortative mating and income inequality in Denmark between 1987 and 2006. Denmark is widely known for its low level of income inequality, but the Danish case provides a good test of the relationship between educational assortative mating and inequality because although income inequality increased over the period we consider, educational homogamy declined. Using register data on the exact incomes of the whole population, we find that change in assortative mating increased income inequality but that these changes were driven by changes in the educational distributions of men and women rather than in the propensity for people to choose a partner with a given level of education.
The Nurse's Role in Providing Information to Surgical Patients and Family Members in Turkey: A Descriptive Study
Authors: Sayin Yazile , Aksoy Güler
Published: May 2012

In 2008, we conducted a nonexperimental, cross‐sectional, descriptive study in the surgical services department of a hospital in Istanbul, Turkey, with the aim of determining how much information was required by perioperative patients and their family members, the extent to which this information was provided, and the role that nurses play in this process. We included a total of 394 outpatients and inpatients and their family members (ie, 197 patients, 197 family members) and 30 nurses in the study. We collected the research data by using one questionnaire for patients, a second for family members of patients, and a third for nurses. We discovered that the patients and their family members wanted to be given more information about the surgical process than they had received. Patients wanted more information about the intraoperative period, whereas their family members wanted more information about the postoperative period. We also found that nurses were aware that they did not play an effective role in providing information to patients and their family members because of a lack of knowledge about what information they were responsible for providing and insufficient staffing. We concluded that nurses should know what education they are responsible for providing, put more effort into understanding patient and family member information needs, and plan a better means of providing information to meet those needs.
Implementing AORN Recommended Practices for Product Selection
Authors: Conrardy Julie A.
Published: May 2012

This article focuses on the revised AORN “Recommended practices for product selection in perioperative practice settings.” Hospitals and ambulatory surgery facilities should have protocols in place for product evaluation that includes a multidisciplinary team approach. The process for product evaluation and selection includes gathering information; establishing consistent requirements for product evaluation; performing a financial impact analysis; investigating a plan to standardize products; conducting an environmental impact analysis; determining whether to purchase single‐use, reposable, or reusable products or reprocess single‐use devices; developing an evaluation process based on objective criteria; and developing and implementing a comprehensive plan to introduce and use new products. Use of an evaluation tool that is based on objective criteria is one way to obtain valuable input during product evaluations. Because of varied roles and experiences, the perioperative RN is an integral member of the product selection committee.