bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Novel Access to 1,4‐Benzodiazepin‐2‐ones via the Buchwald Reaction and Application to the Synthesis of Novel Heterocyclics.
Authors: Salome Christophe , Schmitt Martine , Bourguignon Jean‐Jacques 
Published: May 2012

AbstractA two‐step sequence is presented for the synthesis of biologically interesting title compounds via Buchwald reaction of benzophenone or benzoyl azine derivatives with amides followed by cyclocondensation.
ChemInform Abstract: Palmaenones A and B, Two New Antimicrobial Chlorinated Cyclopentenones from Discomycete Lachnum palmae
Authors: Matsumoto Takunori , Hosoya Tsuyoshi , Tomoda Hiroshi , Shiro Motoo , Shigemori Hideyuki 
Published: May 2012

Abstractisolation and structure elucidation
ChemInform Abstract: Hydrolysable Tannins Isolated from Syzygium aromaticum: Structure of a New C‐Glucosidic Ellagitannin and Spectral Features of Tannins with a Tergalloyl Group
Authors: Bao Li‐Ming , Eerdunbayaer Eerdunbayaer , Nozaki Akiko , Takahashi Eizo , Okamoto Keinosuke , Ito Hideyuki , Hatano Tsutomu 
Published: May 2012

Abstractisolation and structure elucidation of novel tannin, aromatinin A (I)
ChemInform Abstract: 4‐(2‐Hydroxy‐and‐aminoaryl)‐1,2,3‐thia‐and‐selenadiazoles: Synthesis, Reactivity and Applications in Heterocyclic Chemistry
Authors: Androsov Dmitry A. , Petrov Mikhail L. 
Published: May 2012

AbstractReview: 26 refs.
Pricing derivatives on graphics processing units using Monte Carlo simulation
Authors: Abbas‐Turki L.A. , Vialle S. , Lapeyre B. , Mercier P. 
Published: May 2012

SUMMARYThis paper is about using the existing Monte Carlo approach for pricing European and American contracts on a state‐of‐the‐art graphics processing unit (GPU) architecture. First, we adapt on a cluster of GPUs two different suitable paradigms of parallelizing random number generators, which were developed for CPU clusters. Because in financial applications, we request results within seconds of simulation, the sufficiently large computations should be implemented on a cluster of machines. Thus, we make the European contract comparison between CPUs and GPUs using from one up to 16 nodes of a CPU/GPU cluster. We show that using GPUs for European contracts reduces the execution time by ∼ 40 and diminishes the energy consumed by ∼ 50 during the simulation. In the second set of experiments, we investigate the benefits of using GPUs’ parallelization for pricing American options that require solving an optimal stopping problem and which we implement using the Longstaff and Schwartz regression method. The speedup result obtained for American options varies between two and 10 according to the number of generated paths, the dimensions, and the time discretization. Copyright © 2012 John Wiley & Sons, Ltd.
Ethylenediamine inducing growth of {100} facets exposed PbS nanosheets
Authors: Fang Zhen , Wang Qin , Wang Xiaoqing , Zhu Baichuan , Fan Fan , Wang Chenyan , Liu Xiaowang 
Published: May 2012

AbstractA simple ethylenediamine‐assisted hydrothermal method was developed for the synthesis of sheet‐like PbS nanostructures. Studies show that ethylenediamine not only provides a weakly basic environment for the reaction system, but also acts as a capping reagent to control the growth habit of cubic PbS. A reasonable growth mechanism for the PbS nanosheet structure has been proposed on the basis of the experimental studies. The structure, morphology, and composition of the nanosheets have been characterized by X‐ray powder diffraction, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and transmission electron microscopy.
Coarse crystal layer growth and liquid entrapment study with gradient freeze technology
Authors: Jiang Xiaobin , Wang Jingkang , Hou Baohong 
Published: May 2012

AbstractThe coarse crystal layer growth and liquid entrapment processes were investigated with gradient freeze technology in this paper. The research system was hemihydrate phosphoric acid (H3PO4·0.5H2O) crystal‐phosphoric acid aqueous solution. The distribution coefficients of ions (Ca2+, Fe3+ and Na+) in this system were measured. The effect of supercooling degree gradient on layer growth and the effect layer growth rate on ions redistribution were studied. The result indicated that the layer growth rate increased with supercooling degree gradient as an exponential curve. The distribution coefficient tended to increase as an approximate ‘S’ curve when coarse crystal layer growth rate increased. The ‘three region’ theory was applied to explain this phenomenon. Each ion's diffusion parameter was obtained, which contributed to explain the separation differences between different ions. The work in this paper also indicated that layer crystallization was an effective separation technology for electronic grade phosphoric acid preparation.
Identification of novel transcription‐regulating genes expressed during murine molar development
Authors: Uchibe Kenta , Shimizu Hirohito , Yokoyama Shigetoshi , Kuboki Takuo , Asahara Hiroshi 
Published: May 2012

AbstractBackground: The mechanism of tooth development is a complex process regulated by numerous genes including transcription factors, growth factors, and other intra‐ and extracellular molecules. Especially, transcription factors play a central role in gene expression, regulating a wide spectrum of biological processes including organogenesis. Substantial evidence has been demonstrated by a number of studies using genetically engineered animal models. However, detailed molecular mechanisms of tooth development have not been completely elucidated, partially because numerous genes that play essential roles in tooth development remain unidentified. Results: In this study, we conducted an expression‐based screening using gene expression database and in situ hybridization assays. Based on the gene expression database “EMBRYS,” 207 out of 1,520 genes were expressed in the maxillary and/or mandibular processes and thus were selected for further analysis by section in situ hybridization. Among these candidates, 28 genes were newly identified as potential factors associated with tooth development by in situ hybridization assays with frontal sections of embryonic day 13.5 and 14.5 mouse embryos. The expression patterns were also examined at embryonic day 16.5 and 18.5. Conclusions: These results will contribute to elucidating the mechanisms of tooth development and to improving the technology for regeneration of tooth. Developmental Dynamics 241:1217–1226, 2012. © 2012 Wiley Periodicals, Inc.
Regionally nested patterns of fish assemblages in floodplain lakes of the Magdalena river (Colombia)
Authors: Granado‐Lorencio Carlos , Serna Andrés Hernández , Carvajal Juan David , Jiménez‐Segura Luz Fernanda , Gulfo Alejandra , Alvarez Frank 
Published: May 2012

AbstractWe investigated if fish assemblages in neotropical floodplain lakes (cienagas) exhibit nestedness, and thus offer support to the managers of natural resources of the area for their decision making. The location was floodplain lakes of the middle section of the Magdalena river, Colombia. We applied the nested subset analysis for the series of 30 cienagas (27 connected to the main river and three isolated). All fish were identified taxonomically in the field and the matrix for presence–absence in all the lakes was used for the study of the pattern of nestedness. The most diverse order was Characiformes (20 species), followed by Siluriformes (19 species). Characidae and Loricaridae were the richest families. The species found in all the lakes studied were migratory species (17), and sedentary species (33). Two species (Caquetaia kraussii and Cyphocharax magdalenae) were widespread across the cienagas archipelago (100% of incidence). Nestedness analysis showed that the distribution of species over the spatial gradient studied (840 km) is significantly nested. The cienagas deemed the most hospitable were Simiti, El Llanito, and Canaletal. Roughly, 13 out of the 50 species caught show markedly idiosyncratic distributions. The resulting dataset showed a strong pattern of nestedness in the distribution of Magdalenese fishes, and differed significantly from random species assemblages. Out of all the measurements taken in the cienagas, only the size (area) and local richness are significantly related to the range of order of nested subset patterns (r=–0.59 and –0.90, respectively, at p < 0.01). Differential species extinction is suggested as the cause of a nested species assemblage, when the reorganized matrix of species occurring in habitat islands is correlated with the island area. Our results are consistent with this hypothesis.
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

AbstractWe 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.
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

AbstractA 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

AbstractTwo 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.
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

AbstractSafety 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

Abstract
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
How to identify leadership potential: Development and testing of a consensus model
Authors: Dries Nicky , Pepermans Roland 
Published: May 2012

AbstractBuilding 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

AbstractThis 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

AbstractPrevious 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

ObjectivesThe 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.DesignThe 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.ResultsResults 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.ConclusionsOur findings provided relevant data that are informative for preventing alcohol and related risk behaviors among Hispanic college students.