bluuebunny/crossref_metadata_2025 huggingface dataset:
L2 Listening Comprehension: Is it a Language Problem or Listening Problem?
Authors: El-dali Mostafa
Published: January 2017

In a foreign language environment, students typically have limited exposure to the language outside formal classrooms. Therefore, their ability to comprehend spoken English may be limited. To add to this problem, L2 learners often regard listening as the most difficult language skill to learn. On the other hand, it is noticeable that L2 listening remains the least researched of all four language skills. Accordingly, the present study is based on the commonly believed premises that (1) investigating the listening comprehension process can provide useful insights into teaching listening and (2) learners who learn to control their listening process can enhance their comprehension, and their overall proficiency may be highly developed.The present study reports on the results of an empirical study on forty-six L2 learners of English. The subjects were equally divided into two groups. The first group (N=23) represents first year students (Beginners) in the Department of English at the Faculty of Education, Menufia University, Egypt. The second group (N=23) represents fourth year students (Advanced) in the same department. The major question that this study attempts to answer is “whether listening comprehension a language problem or listening problem?” The instruments of this study consist of five tasks: pre-test, questionnaire, classroom instruction sessions, post-test, and interviews. The data analysis had a quantitative and a qualitative part. Results were obtained and conclusions were made.
Developing a Simulated-Person Methodology Workshop: An Experiential Education Initiative for Educators and Simulators
Authors: Peisachovich Eva Hava , Nelles LJ , Johnson Samantha , Nicholson Laura , Gal Raya , Kerr Barbara , Popovic Celia , Epstein Iris , Silva Celina Da
Published: January 2017

Numerous forecasts suggest that professional-competence development depends on human encounters. Interaction between organizations, tasks, and individual providers influence human behaviour, affect organizations’ or systems’ performance, and are a key component of professional-competence development. Further, insufficient or ineffective communication between professionals is deemed a contributing factor to adverse events worldwide. This underscores the need to provide educators with the tools and education to embed methods in their teaching that will enable learners to effectively intervene in highly charged interpersonal situations and high-risk scenarios; these concerns highlight the value of realistic simulated-experiential approaches, such as the one proposed in this project.  The first phase of this project involved conducting a three-day experiential workshop developed at a Canadian university to provide educators with knowledge and skills to work and effectively utilize simulators, enhancing pedagogical classroom practices for teaching undergraduate learners. This workshop’s development resulted in numerous benefits. Participation in the workshop provided educators with opportunities for meaningful reflection on their teaching practice and the ability to apply this insight to optimize student learning. It provided theatre students, recruited as simulators as part of this interdisciplinary initiative, to expand their experiences and this will lead to an expanded practicum course for their program.  There is now a group of simulators available to educators across the university to include in classroom activities, and lastly there are further iterations of this workshop available for faculty development. This paper reflects on the workshop experiences and the feedback obtained from the participants. Formal and informal feedback obtained provides an understanding of the participants’ experiences.
Solving a Mixed Problem with Almost Regular Boundary Condition By the Contour Integral Method
Authors: Aleskerova S. T.
Published: January 2017

In the paper, a mixed problem for $\lambda $-complex parameter dependent, fourth order partial equation is considered. The estimations for the Green function for the eigenvalues of the considered problem outside of $\delta $ were obtained within the regular boundary condition. The solution of the mixed problem was given in the  contour integral form.
Editorial
Authors: Weber Mary Beth
Published: January 2017

I can tell when a new semester has begun at my institution. Suddenly there is double the amount of traffic, it takes me longer to drive to meetings on other campuses, and it is difficult to find a parking spot, particularly when I have afternoon meetings. I can no longer leave fifteen minutes before a meeting, find a parking spot, and be on time for my meeting. My commute to work also takes longer since there are more cars on the road due to faculty and students returning to school, plus there are school buses for the K-12 students from the surrounding areas. The beginning of each semester also leads to rush orders, reserve orders, and rush cataloging. While semesters change, the demand for technical services work remains steady. I am always surprised when people ask if I am employed for twelve months (they may think I get summers off because I have faculty status) or if my work slows down in the summer.
Book Review: An Emergent Theory of Digital Library Metadata
Authors: Shoemaker Elizabeth
Published: January 2017

This slim volume is a recent release in the long-running Chandos Information Professional Series. Author Getaneh Alemu has an international work history, and is currently cataloguing and metadata librarian at Southampton Solent University in the United Kingdom. Co-author Brett Stevens is a lecturer in the School of Creative Technologies a few miles down the road at the University of Portsmouth.
Sentimentos e expectativas vivenciados pelas adolescentes ao se tornarem mães: nota prévia
Authors: Silveira Jéssica Rodrigues , Cremonese Luiza , Wilhelm Laís Antunes , Prates Lisie Alende , Oliveira Gabriela , Ressel Lúcia Beatriz
Published: January 2017

Objetivo: conhecer os sentimentos e expectativas vivenciados por mulheres adolescentes ao se tornarem mães. Método: estudo de campo, descritivo, com abordagem qualitativa. O cenário de estudo é um hospital do interior do Rio Grande do Sul, o período de coleta de dados foi outubro e novembro de 2016. As participantes da pesquisa são adolescentes no período de pós-parto mediato. Os dados foram coletados por meio de uma entrevista semiestruturada e, após, serão analisados através da proposta operativa de Minayo. Resultados esperados: espera-se que este estudo promova discussões e reflexões que auxiliem na compreensão dos sentimentos e expectativas vivenciados pelas jovens adolescentes ao se tornarem mães.
ALFARO-LEFREVE, Rosalinda. E-Study Guide for: Applying Nursing Process: A Tool for Critical Thinking. Cram101 Textbook Reviews, 2014. 66p.
Authors: Carvalho Diana Paula de Souza Rego Pinto , Lima Jéssica Valeska Herculano , Rego Anna Larissa de Castro , Câmara Priscila Fernandes Meireles , Azevedo Isabelle Campos de , Ferreira Júnior Marcos Antonio
Published: January 2017

Lançado em 2014 pela editora Cram101 Textbook Reviews, o E-Study Guide for: Applying Nursing Process: A tool for Critical Thinking é um guia de estudo eletrônico, disponível apenas no idioma inglês no formato e-book, que descreve termos conhecidos pelos profissionais da área de enfermagem de uma forma didática, além de oferecer testes práticos ao final de cada capítulo. A obra em questão obteve destaque por facilitar o entendimento de conteúdos difíceis e no auxilio a estudantes, enfermeiros, professores e gestores no desenvolvimento do pensamento crítico, crescimento profissional e processo de enfermagem.
Percepção de usuários hospitalizados sobre o atendimento nos serviços de saúde
Authors: Siqueira Pâmela Guimarães , Silva Rosângela Marion da , Beck Carmem Lúcia Colomé , Prestes Francine Cassol , Vedootto Denise De Oliveira , Pasa Thiana Sebben
Published: January 2017

Objetivo: conhecer a percepção de usuários hospitalizados sobre o atendimento nos serviços de saúde. Método: pesquisa qualitativa, descritiva e exploratória, realizada em uma unidade de Clinica Cirúrgica, no período de outubro a novembro de 2014. Os dados foram obtidos por meio de entrevistas semiestruturadas com usuários internados e analisados a partir da análise temática. Resultados: os resultados foram discutidos a partir das categorias: o caminhar nos serviços de saúde; e realidades da Atenção Primária à Saúde e da hospitalar. Identificou-se que os usuários percebem que o atendimento recebido nos serviços de saúde é dificultado pela falta de estrutura dos mesmos, pela comunicação deficiente ou inexistente e pela falta de humanização na assistência. Conclusão: Frente às dificuldades percebidas nos serviços de atenção primária à saúde, os usuários buscam atendimento em instituições hospitalares, situação que desfavorece o estabelecimento e a articulação das redes de atenção à saúde.
EDITORIAL - REVISTA SOCIAIS E HUMANAS
Authors: Kocourek Sheila
Published: January 2017

Na segunda edição de 2016, a Revista Sociais e Humanas [RSH] do Centro de Ciências Sociais e Humanas da Universidade Federal de Santa Maria conta com 10 artigos, contribuições oriundas de Rondônia, São Paulo, Goiás, Rio Grande do Sul e Santa Catarina. As temáticas versam sobre as seguintes áreas da RSH: Psicologia, Políticas Públicas, História, Cultura Regional, Administração, Educação, Arquivologia, Gestão de Turismo, Política Pública em Saúde.
DIFERENCIAIS DO SISTEMA COOPERATIVO SICREDI: ANÁLISE DAS DEMONSTRAÇÕES FINANCEIRAS NOS ANOS DE 2012 A 2014
Authors: Jesus Ariane Saraiva de , Almeida Carla Letícia de
Published: January 2017

A concessão de crédito no Brasil ainda é uma realidade multifacetada e, para suprir a necessidade de capital no mercado, aparecem iniciativas populares que têm, continuamente, se destacado na economia mundial, entre elas o foco deste artigo: cooperativas de crédito. O cooperado é, ao mesmo tempo, cliente, dono e fornecedor da cooperativa. Devido a essa capilaridade, questiona-se se é possível avaliar uma cooperativa por meio de indicadores tradicionais. Utilizando pesquisas bibliográficas, o objetivo deste artigo fora avaliar a estrutura de capital do Sistema Cooperativo Sicredi, analisando sua flexibilidade na gestão e sua proximidade com o cooperado e, consequentemente, seu impacto nos indicadores de rentabilidade, solvência e de endividamento. É possível concluir que por ser uma instituição diferenciada, merece também uma interpretação diferenciada de seus indicadores, assim, sua forma de captação e de aplicação de recursos favorece o crescimento contínuo de sua margem de rentabilidade sob os serviços oferecidos tornando-o um sistema eficiente de cooperativismo.
Le système d’emploi des travailleurs agricoles saisonniers : portrait d’un rapport salarial multipartite
Authors: Gesualdi-Fecteau Dalia
Published: January 2017

Les programmes de migration temporaire constituent une manifestation de la division internationale du travail qui se concrétise par le déplacement de la main-d’oeuvre. Les travailleurs étrangers temporaires et leurs employeurs s’insèrent dans un système d’emploi qui se caractérise par l’action intervenant à l’occasion de la formation, de l’exécution et de la terminaison du rapport salarial. Or, si l’action intervenant au sein d’un système d’emploi résulte notamment des effets des règles juridiques applicables, elle découle également des schémas d’action mis de l’avant par les acteurs qui y interagissent. Cependant, certains de ces acteurs sont susceptibles d’occuper, de façon singulière, la scène de l’action : la prégnance de leurs schémas d’action est directement proportionnelle à la nature et à la portée du rôle qu’ils assument dans le système d’emploi.

Cet article présente les résultats d’une étude de terrain qui a permis de cerner les contours du système d’emploi dans lequel s’insèrent les travailleurs agricoles guatémaltèques embauchésviale « Volet agricole » duProgramme des travailleurs étrangers temporaires. Notre recherche révèle de quelle façon s’organise la capacité d’action des acteurs exogènes et endogènes au champ du travail. Elle permet également de comprendre de quelle façon certains acteurs sont contraints par l’effet de frontières géographiques et systémiques. Finalement, l’appréhension empirique du système d’emploi étudié amène aussi à brosser le portrait d’un rapport salarial multipartite tout à fait singulier.
Labour Standards in Global Value Chains: Disentangling Workers’ Voice, Vicarious Voice, Power Relations, and Regulation
Authors: Josserand Emmanuel , Kaine Sarah
Published: January 2017

Theoretical developments and case studies have started to explore the complexity and intricacies of new forms of labour regulation in Global Value Chains (GVCs). This paper builds on these to integrate what we know into a coherent framework that can guide practice and future research. We bring together existing knowledge on new forms of labour standards regulation—such as Private Social Standards (PSSs) and International Framework Agreements (IFAs)—into a framework that integrates and disentangles the contextual determinants, processes, regulatory mechanisms, and outcomes of such regulation in GVCs. Of special significance is the distinction between regulatory processes—vicarious voice, workers’ voice, coordinated international campaigns—, and regulatory mechanisms—IFAs and PSSs. Extant literature tends to deal with existing forms of regulation without much clarity on their respective roles. Our framework identifies two pathways from regulatory processes to regulatory mechanisms: the labour power and the customer power pathways. Our framework also establishes clear connections between concepts, underlining links of causality and moderating effects.

We explore the impact of value chain structure, and specifically, the connections between workers’ and vicarious voice, on regulatory outcomes. With regard to the structure of supply chains, we examine the coupling of operations and the sensitivity of value chain participants to reputational risk and drive within value chains. We add the significant dimension of ‘internal drive’ to existing understandings of drive to capture the possible internal discrepancies leading managers in multinational companies (MNCs) to apply mixed incentives to their suppliers to comply with labour standards. Additionally, we introduce the concept of ‘vicarious voice’, which we define as a situation where workers’ voice is substituted by that of actors who, unlike local unions or activist unionism, do not have a close representative link with workers. Vicarious voice may be composed of ethical consumerism, social advocacy, and international union federations.
Psyllid Species (Cacopsylla spp.) in Pear Orchards of East Sarajevo
Authors: Tešanović Dejana , Spasić Radoslava , Jerinić Prodanović Dušanka
Published: January 2017

Psyllid species (Cacopsylla spp.) are the most important pests on pear in all regions where this fruit species is grown. Cacopsylla spp. cause direct and indirect damages because they suck the sap and make large amounts of honeydew, which disturbs the normal physiological processes.  Some psyllid species vectors of phytoplasma were found (Carraro i sar., 1998). The survey was done in 2011 and 2012 in orchards, in the locations of Vojkovici, Kula, Tilava, Petrovići and Kasindo. In Kula location, survey was done on the following cultivars: Wiliams, General Le Clerc, „Passa Crasana“, Abe Fetel and Poire de Curé. In pear orchards of the East Sarajevo area the following were determined: Cacopsylla pyri Linne, Cacopsylla pyrisuga Foerster and Cacopsylla pyricola Foerster. In intensive orchards of Vojkovići and Kula, C. pyri was more present compared to C. pyrisuga, while in extensive orchards in the location of Kasindo, C. pyrisuga was more present.  In semi-intensive orchards, Tilava and Petrovići, the most present was C. pyrisuga, then C. pyri and the least present was C. pyricola. In the locality of Kula, the highest percentage of shoots infeted with C. pyri was the Poire de Curé, and the smallest was of cultivar Abe Fetel.
Peptide‐Passivated Lead Halide Perovskite Nanocrystals Based on Synergistic Effect between Amino and Carboxylic Functional Groups
Authors: Luo Binbin , Naghadeh Sara Bonabi , Allen A'Lester , Li Xueming , Zhang Jin Z.
Published: January 2017

A new strategy has been developed using peptides with amino and carboxylic functional groups as passivating ligands to produce methyl ammonium lead bromide (CH3NH3PbBr3) perovskite nanocrystals (PNCs) with excellent optical properties. The well‐passivated PNCs can only be obtained when both amino and carboxylic groups are involved, and this is attributed to the protonation reaction between NH2 and COOH that is essential for successful passivation of the PNCs. To better understand this synergistic effect, peptides with different lengths have been studied and compared. Due to the polar nature of peptides, peptide‐passivated PNCs (denoted as PNCspeptide) aggregate and precipitate from nonpolar toluene solvent, resulting in a high product yield (≈44%). Furthermore, the size of PNCspeptide can be varied from ≈3.9 to 8.6 nm by adjusting the concentration of the peptide, resulting in tunable optical properties due to the quantum confinement effect. In addition, CsPbBr3 PNCs are also synthesized with peptides as capping ligands, further demonstrating the generality and versatility of this strategy, which is important for generating high quality PNCs for photonics applications including light‐emitting diodes, optical sensing, and imaging.
Unconventional Molecular Weight Dependence of Charge Transport in the High Mobility n‐type Semiconducting Polymer P(NDI2OD‐T2)
Authors: Nahid Masrur M. , Matsidik Rukiya , Welford Adam , Gann Eliot , Thomsen Lars , Sommer Michael , McNeill Christopher R.
Published: January 2017

The charge transport and microstructural properties of five different molecular weight (MW) batches of the naphthalenediimide‐thiophene copolymer P(NDI2OD‐T2) are investigated. In particular, the field‐effect transistor (FET) performance and thin‐film microstructure of samples with MW varying from Mn = 10 to 41 kDa are studied. Unlike conventional semiconducting polymers such as poly(3‐hexylthiophene) where FET mobility dramatically drops with decreasing molecular weight, the FET mobility of P(NDI2OD‐T2)‐based transistors processed from 1,2‐dichlorobenzene is found to increase with decreasing MW. Using a combination of grazing‐incidence wide‐angle X‐ray scattering, near‐edge X‐ray absorption fine‐structure spectroscopy, atomic force microscopy, and resonant soft X‐ray scattering, the increase in FET mobility with decreasing MW is attributed to the pronounced increase in the orientational correlation length (OCL) with decreasing MW. In particular, the OCL is observed to systematically increase from <100 nm for the highest MW samples to ≈1 µm for the lowest MW samples. The improvement in OCL and hence mobility for low MW samples is attributed to the lack of aggregation of low MW chains in solution promoting backbone ordering, with the pre‐aggregation of chains in 1,2‐dichlorobenzene found to suppress longer‐range liquid crystalline order.
Lattice‐Symmetry‐Driven Epitaxy of Hierarchical GaN Nanotripods
Authors: Wang Ping , Wang Xinqiang , Wang Tao , Tan Chih‐Shan , Sheng Bowen , Sun Xiaoxiao , Li Mo , Rong Xin , Zheng Xiantong , Chen Zhaoying , Yang Xuelin , Xu Fujun , Qin Zhixin , Zhang Jian , Zhang Xixiang , Shen Bo
Published: January 2017

Lattice‐symmetry‐driven epitaxy of hierarchical GaN nanotripods is demonstrated. The nanotripods emerge on the top of hexagonal GaN nanowires, which are selectively grown on pillar‐patterned GaN templates using molecular beam epitaxy. High‐resolution transmission electron microscopy confirms that two kinds of lattice‐symmetry, wurtzite (wz) and zinc‐blende (zb), coexist in the GaN nanotripods. Periodical transformation between wz and zb drives the epitaxy of the hierarchical nanotripods with N‐polarity. The zb‐GaN is formed by the poor diffusion of adatoms, and it can be suppressed by improving the ability of the Ga adatoms to migrate as the growth temperature increased. This controllable epitaxy of hierarchical GaN nanotripods allows quantum dots to be located at the phase junctions of the nanotripods and nanowires, suggesting a new recipe for multichannel quantum devices.
Declamped Piezoelectric Coefficients in Patterned 70/30 Lead Magnesium Niobate–Lead Titanate Thin Films
Authors: Keech Ryan , Ye Linghan , Bosse James L. , Esteves Giovanni , Guerrier Jonathon , Jones Jacob L. , Kuroda Marcelo A. , Huey Bryan D. , Trolier‐McKinstry Susan
Published: January 2017

Lateral subdivision of blanket piezoelectric thin films increases the functional properties through both increased domain wall mobility and declamping of the intrinsic response. This work presents the local effects of substrate declamping on the piezoelectric coefficient d33,f of 300 nm thick, rhombohedral, {001}‐oriented lead magnesium niobate–lead titanate thin films at the 70/30 composition (70PMN–30PT). Films grown by chemical solution deposition on platinized Si substrates are patterned into strip structures ranging from 0.75 to 9 µm in width. The longitudinal piezoelectric coefficient, d33,f, is interrogated as a function of position across the patterned structures by three approaches: finite element modeling, piezoresponse force microscopy, and nanoprobe synchrotron X‐ray diffraction. It is found that d33,f increases from the clamped value of 40–50 to ≈160 pm V−1 at the free sidewall under 200 kV cm−1 excitation. The sidewalls partially declamp the piezoelectric response 500–600 nm into the patterned structure, raising the piezoelectric response at the center of features with lateral dimensions less than 1 µm (3:1 width to thickness aspect ratio). The normalized data from all three methods are in excellent agreement, with quantitative differences providing insight to the field dependence of the piezoelectric coefficient and its declamping behavior.
New Apatite‐Type Oxide Ion Conductor, Bi2La8[(GeO4)6]O3: Structure, Properties, and Direct Imaging of Low‐Level Interstitial Oxygen Atoms Using Aberration‐Corrected Scanning Transmission Electron Microscopy
Authors: Tate Matthew L. , Blom Douglas A. , Avdeev Maxim , Brand Helen E. A. , McIntyre Garry J. , Vogt Thomas , Evans Ivana Radosavljevic
Published: January 2017

The new solid electrolyte Bi2La8[(GeO4)6]O3 is prepared and characterized by variable‐temperature synchrotron X‐ray and neutron diffraction, aberration‐corrected scanning transmission electron microscopy, and physical property measurements (impedance spectroscopy and second harmonic generation). The material is a triclinic variant of the apatite structure type and owes its ionic conductivity to the presence of oxide ion interstitials. A combination of annular bright‐field scanning transmission electron microscopy experiments and frozen‐phonon multislice simulations enables direct imaging of the crucial interstitial oxygen atoms present at a level of 8 out of 1030 electrons per formula unit of the material, and crystallographically disordered, in the unit cell. Scanning transmission electron microscopy also leads to a direct observation of the local departures from the centrosymmetric average structure determined by diffraction. As no second harmonic generation signal is observed, these displacements are non‐cooperative on the longer length scales probed by optical methods.
Visible Light‐Induced Decarboxylative Acylarylation of Phenyl Propiolates with α‐Oxocarboxylic Acids to Coumarins Catalyzed by Hypervalent Iodine Reagents under Transition Metal‐Free Conditions
Authors: Yang Shuai , Tan Hui , Ji Wangqin , Zhang Xiangbiao , Li Pinhua , Wang Lei
Published: January 2017

No Abstract

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Copper‐Catalyzed 1,6‐Hydrodifluoroacetylation of para‐Quinone Methides at Ambient Temperature with Bis(pinacolato)diboron as Reductant
Authors: Ke Miaolin , Song Qiuling
Published: January 2017

An original and efficient copper‐catalyzed 1,6‐hydrodifluoroacetylation of para‐quinone methides with difluoroalkyl bromides has been described with bis(pinacolato)diboron (B2pin2) as reductant. In this reaction, a new C(sp3)–CF2 bond is constructed under smart conditions. A broad substrate scope of para‐quinone methides (p‐QMs) make this protocol very practical and attractive. Preliminary mechanistic studies manifested that a difluoroalkyl radical pathway was involved in this reaction. Also the presence of the diboron reagent was an essential requisite in this transformation.

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Gold‐Catalyzed 1,4‐Carbooxygenation of 3‐En‐1‐ynamides with Allylic and Propargylic Alcohols via Non‐Claisen Pathways
Authors: Giri Sovan Sundar , Lin Li‐Hsuan , Jadhav Prakash Daulat , Liu Rai‐Shung
Published: January 2017

Gold‐catalyzed 1,4‐carbooxygenations of 3‐en‐1‐ynamides with allylic alcohols and propargylic alcohols yield α,β‐unsaturated amides through non‐Claisen pathways; the mechanisms involve ionization of the initial gold enol ethers to form C‐bound gold dienolates that capture allylic or propargylic cations to yield the observed products. Our 18O‐labeling experiments exclude a direct gold‐catalyzed allylation or propargylation on these 3‐en‐1‐ynamides.

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Advances in Asymmetric Diastereodivergent Catalysis
Authors: Bihani Manisha , Zhao John C.‐G.
Published: January 2017

Because the biological and/or pharmacological properties of a given molecule often depend on the absolute and relative configurations of the stereogenic centers, different diastereomers may exhibit totally different biological and/or pharmacological activities. Therefore, for compounds containing multiple stereogenic centers, the stereoselective asymmetric synthesis of all of the individual diastereomers, preferably using a catalytic method, is of great interest and importance in organic synthesis and drug discovery. In this context, the development of catalytic diastereodivergent methods is highly desirable, since it provides one of the most efficient ways to access multiple diastereomers from the same substrates. The current review attempts to summarize the developments in the field of asymmetric diastereodivergent catalysis.

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Tetrahydropyran‐Based Hybrid Dipeptides as Asymmetric Catalysts for Michael Addition of Aldehydes to β‐Nitrostyrenes
Authors: Borges‐González Jorge , Feher‐Voelger Andrés , Crisóstomo Fernando Pinacho , Morales Ezequiel Q. , Martín Tomás
Published: January 2017

A new series of hybrid dipeptide‐like organocatalysts based on pyranoid ϵ‐ or ζ‐amino acids and proline have been prepared for the asymmetric Michael addition of aldehydes to β‐nitrostyrenes. The reaction proceeds under mild conditions to afford a wide range of γ‐nitroaldehydes with up to 98% yield and up to 96% ee. These dipeptides are bifunctional organocatalysts, with a proline at the N‐terminus and a carboxylic acid at the C‐terminus. The tetrahydropyran unit embedded in the ϵ‐ or ζ‐amino acid induces a well‐defined conformation that is responsible for the catalysis. These dipeptides represent a new type of organocatalyst with a large number of possibilities to modulate their reactivity and selectivity.

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Exploiting the Biocatalytic Toolbox for the Asymmetric Synthesis of the Heart‐Rate Reducing Agent Ivabradine
Authors: Pedragosa‐Moreau Sandrine , Le Flohic Alexandre , Thienpondt Vivien , Lefoulon François , Petit Anne‐Marie , Ríos‐Lombardía Nicolás , Morís Francisco , González‐Sabín Javier
Published: January 2017

Several chemoenzymatic routes have been evaluated for the production of the heart‐rate reducing agent ivabradine. Lipases and ω‐transaminases have been identified as useful biocatalysts for the preparation of key enantiopure precursors. The lipase‐catalysed kinetic resolution by alkoxycarbonylation of a racemic primary amine and subsequent chemical reduction of the resulting carbamate provided an N‐methylated (S)‐amine, one step away from ivabradine. Alternatively, the dynamic kinetic resolution by asymmetric bioamination of an aldehyde precursor enabled, in a four‐step sequence, the preparative scale synthesis of enantiopure ivabradine in 50% overall yield.

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Hydrogen Isotope Exchange with Iridium(I) Complexes Supported by Phosphine‐Imidazolin‐2‐imine P,N Ligands
Authors: Jess Kristof , Derdau Volker , Weck Remo , Atzrodt Jens , Freytag Matthias , Jones Peter G. , Tamm Matthias
Published: January 2017

Phenylene‐bridged hybrid phosphine‐imidazolin‐2‐imine RP,NR′ ligands (R=Ph, Cy, i‐Pr, t‐Bu; R′=Me, i‐Pr) were prepared from 1,2‐dibromobenzene by palladium‐catalyzed C–N coupling with 1,3,4,5‐tetramethylimidazolin‐2‐imine or 1,3‐diisopropyl‐4,5‐dimethylimidazolin‐2‐imine, followed by lithiation with tert‐butyllithium and reaction with the chlorophosphines (R2PCl). Their reaction with the dimeric iridium complex [Ir(cod)Cl]2 (cod=1,5‐cyclooctadiene) and subsequent anion exchange with sodium tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate (NaBArF24) or potassium hexafluorophosphate (KPF6) afforded iridium complexes of the type [(RP,NR′)Ir(cod)]BArF24 or [(RP,NR′)Ir(cod)]PF6, respectively. The latter PF6 salts were structurally characterized, revealing short Ir—N bonds as an indication of electron‐rich nitrogen donor atoms. The former complexes were tested for their applicability in catalytic H/D exchange. In particular, the complex with the ligand t‐BuP,NMe showed remarkable performance in H/D exchange with a broad range of aromatic substrates, including ketones, amides, esters, heterocycles and nitro compounds, and also promoted H/D exchange at aromatic Boc‐protected amines, benzylamines and methoxy derivatives.

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“Naked” Iridium(IV) Oxide Nanoparticles as Expedient and Robust Catalysts for Hydrogenation of Nitrogen Heterocycles: Remarkable Vicinal Substitution Effect and Recyclability
Authors: Ji Yi‐Gang , Wei Kai , Liu Teng , Wu Lei , Zhang Wei‐Hua
Published: January 2017

Iridium(IV) oxide nanoparticles were facilely prepared from iridium trichloride hydrate and sodium hydroxide by a ball‐milling reaction at room temperature. The “naked” iridium nanocatalyst showed high stability and activity for the hydrogenation of a series of nitrogen heterocycles, for the first time, under a hydrogen balloon at room temperature with a selectivity of higher than 99%. Besides, an unprecedented substitution‐dependent effect was discovered, where substrates with vicinal substituents on 2‐, 3‐, or 8‐positions exhibited distinctly higher reaction rates than unsubstituted or remote substituted ones. Extraordinary recyclability was discovered in the hydrogenation of 2‐methylquinoline for 30 runs without loss of activity.

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Validation of an enzyme immunoassay and comparison of fecal cortisol metabolite levels in black and gold howler monkeys (Alouatta caraya) inhabiting fragmented and continuous areas of the humid Chaco region, Argentina
Authors: Cantarelli Verónica Inés , Perez‐Rueda Maria Amparo , Kowalewski Martin M. , Mastromonaco Gabriela F. , Ponzio Marina Flavia
Published: January 2017

In the last years, the study of how environmental stimuli influence the physiology and specifically the endocrinology of an organism became increasingly important, relying mainly on the quantification of glucocorticoids to monitor animal welfare. Most studies investigating cortisol levels in primates were focused on the impact of social stressors; however, a major concern for the conservation of howler monkeys is the increased habitat fragmentation led by the advancement of the agricultural frontier. We compared fecal cortisol metabolite levels (FGCM) in howler monkeys (Alouatta caraya) living in fragmented and continuous forests of the Argentine humid Chaco region, throughout the warm season (spring‐summer). Fecal samples (n = 114) were collected from adult individuals, and steroid extracts analyzed with an enzyme immunoassay also validated in this work. Parallel displacement curves were obtained between dilutions of pooled fecal extracts and the cortisol standard curve (r2 = 0.99; P = 0.23). Efficiency of the fecal extraction procedure was 79.4% ± 38%; recovery of exogenous hormone added to fecal extracts indicated a low interference of components in the feces with antibody binding. The exogenous administration of ACTH in captive‐bred animals demonstrated a “cause‐and‐effect” relationship between the adrenal gland activation and increased FGCM levels. Contrary to our initial prediction, we were not able to demonstrate a significant difference in FGCM levels of caraya monkeys inhabiting the continuous versus fragmented habitats in our study site (83.2 ± 4.9 ng/g [n = 10 individuals] vs. 71.5 ± 4.9 ng/g [n = 7 individuals]; P = 0.29); this could be the result of low levels of disturbance imposed by a moderate and selective logging, which has proved to be beneficial for this species with high resilience by adjusting their diet to cope with feeding in degraded habitats but with new leaves and buds. Regardless of the habitat, cortisol metabolites were significantly higher in females than in males (86.4 ± 4.2 ng/g [n = 12 individuals] vs. 60.7 ± 5.0 ng/g [n = 5 individuals] respectively; P = 0.007).

RESEARCH HIGHLIGHTS

Validation of an enzyme immunoassay and comparison of fecal cortisol metabolite levels in black and gold howler monkeys (Alouatta caraya) inhabiting fragmented and continuous areas of the humid Chaco region, Argentina. Contrary to our initial prediction, no significant differences in Alouatta caraya fecal cortisol metabolite levels were detected; cortisol metabolites were significantly higher in females. Probably, animals adjusted their diet to cope with feeding in degraded habitats, but with new leaves and buds.
In‐vivo‐Dearomatisierung des potenten Antituberkulose‐Wirkstoffs BTZ043 durch Bildung eines Meisenheimer‐Komplexes
Authors: Kloss Florian , Krchnak Viktor , Krchnakova Anna , Schieferdecker Sebastian , Dreisbach Julia , Krone Volker , Möllmann Ute , Hoelscher Michael , Miller Marvin J.
Published: January 2017

Nitrobenzothiazinone gehören zu den potentesten Antituberkulose‐Wirkstoffen. Hier beschreiben wir eine In‐vivo‐Reduktion der beiden klinischen Kandidaten BTZ043 und PBTZ169, die zur Bildung von Meisenheimer‐Komplexen führt. Diese Reduktion ist reversibel, tritt in allen untersuchten Säugetierspezies auf und hat einen erheblichen Einfluss auf In‐vivo‐ADME‐Charakteristiken und signifikante Auswirkungen auf das Design und die Durchführung von klinischen Studien. Die Reduktion wurde durch chemische Untersuchungen verifiziert, die eine vollständige Charakterisierung des Meisenheimer‐Komplexes und dessen Folgechemie ermöglichten. Die Kombination von In‐vivo‐Studien mit chemischen Arbeiten, wie der LC‐MS‐basierten Charakterisierung und der Assay‐Entwicklung, bildet die Grundlage für eine rationale Leitstrukturoptimierung dieser vielversprechenden Klasse von Antituberkulose‐Wirkstoffen.
Die Lösung des Rätsels um den Verlust eines Kohlenstoffatoms in der Ripostatin‐Biosynthese
Authors: Fu Chengzhang , Auerbach David , Li Yanyan , Scheid Ullrich , Luxenburger Eva , Garcia Ronald , Irschik Herbert , Müller Rolf
Published: January 2017

Ripostatin ist ein vielversprechendes Antibiotikum, welches die RNA‐Polymerase an einer neuen Bindestelle hemmt. Im Mittelpunkt dieser Studie steht die Charakterisierung der Ripostatin‐Biosynthese, die durch eine ungewöhnliche, sowohl auf trans‐ als auch cis‐Acyltransferasen beruhenden hybriden Polyketidsynthase getrieben wird. Im Besonderen beschreiben wir einen bisher unbekannten Mechanismus zur Bildung einer Phenylessigsäure‐Starteinheit, welche durch die Decarboxylierung von Phenylpyruvat gebildet wird. Die Entstehung dieser Starteinheit konnte in vitro rekonstituiert werden, was einen Mechanismus offenlegte, der dem des Pyruvatdehydrogenase‐Komplexes ähnlich ist. Dieser enyzmatische Prozess entfernt ein einzelnes Kohlenstoffatom aus Phenylpyruvat in einer Thiaminpyrophosphat‐abhängigen Decarboxylierung. Die dabei letztlich gebildete Phenylacetyl‐S‐acyl‐Spezies dient als Starteinheit der Ripostatin‐Biosynthese.
Reduktive Dehydrierung eines Stannans durch mehrfache Sn‐H‐Aktivierung mit einem frustrierten Lewis‐Paar
Authors: Sindlinger Christian P. , Aicher Frederik S. W. , Schubert Hartmut , Wesemann Lars
Published: January 2017

Ein sterisch anspruchsvoll substituiertes Stannan Ar*SnH3 (Ar*=2,6‐(2′,4′,6′‐Triisopropylphenyl)phenyl) wurde mit dem bekannten frustrierten Lewis‐Paar (FLP) PtBu3/B(C6F5)3 in verschiedenen stöchiometrischen Zusammensetzungen umgesetzt. Unter anderem wurde die Hydridabstraktion und Adduktbildung beobachtet, die zum SnIV‐Kation [Ar*SnH2(PtBu3)]+ führt. Dieses zeigte sich gegenüber weiterer Wasserstoffabstraktion reaktionsträge. In einem hierzu konkurrierenden Prozess wurde hingegen vollständige Entfernung der Wasserstoffatome beobachtet, was zum ersten kationischen Phosphoniostannylen [Ar*Sn(PtBu)]+ führt. Dieses Reaktionsverhalten lässt Rückschlüsse auf die involvierten Prozesse der Wasserstoff‐/Hydridabstraktion dieser Gruppe‐14‐Hydridderivate zu.
Synthesis of Bradyrhizose Oligosaccharides Relevant to the Bradyrhizobium O‐Antigen
Authors: Li Wei , Silipo Alba , Gersby Lotte Bettina Andersen , Newman Mari‐Anne , Molinaro Antonio , Yu Biao
Published: January 2017

The unique α‐(1→7)‐bradyrhizoside linkages are constructed for the first time via judicious choice of the glycosylation partners and conditions, thus tetra‐ and penta‐bradyrhizosides relevant to the peculiar O‐antigen of Bradyrhizobium are synthesized, which are shown to adopt the defined right‐handed helical conformations and to be unable to induce innate immune responses in plants.
Social Self‐Sorting of Colloidal Families in Co‐Assembling Microgel Systems
Authors: Han Kang , Go Dennis , Tigges Thomas , Rahimi Khosrow , Kuehne Alexander J. C. , Walther Andreas
Published: January 2017

Colloids are valuable model systems to understand the structure and dynamics of matter, explore new self‐assembly concepts, and realize advanced materials. Herein, we demonstrate social self‐sorting of co‐assembled families of colloids by orthogonal host/guest recognition using cyclodextrins. We show that mixtures of four partners self‐sort into their respective families without mutual interference. Additionally, the self‐assemblies and their interactions are switchable using orthogonal triggers. This study goes beyond previous features of molecular self‐sorting, and opens the design space for future self‐sorting colloidal systems via rationally designed molecular recognition.
In Vivo Dearomatization of the Potent Antituberculosis Agent BTZ043 via Meisenheimer Complex Formation
Authors: Kloss Florian , Krchnak Viktor , Krchnakova Anna , Schieferdecker Sebastian , Dreisbach Julia , Krone Volker , Möllmann Ute , Hoelscher Michael , Miller Marvin J.
Published: January 2017

Nitrobenzothiazinones are among the most potent antituberculosis agents. Herein, we disclose an unprecedented in vivo reduction process that affords Meisenheimer complexes of the clinical candidates BTZ043 and PBTZ169. The reduction is reversible, occurs in all mammalian species investigated, has a profound influence on the in vivo ADME characteristics, and has considerable implications for the design and implementation of clinical studies. The reduction was confirmed by chemical studies that enabled the complete characterization of the Meisenheimer complex and its subsequent chemistry. Combination of the in vivo and chemical studies with LC‐MS characterization and assay development also provides a basis for rational lead optimization of this very promising class of antituberculosis agents.
Solving the Puzzle of One‐Carbon Loss in Ripostatin Biosynthesis
Authors: Fu Chengzhang , Auerbach David , Li Yanyan , Scheid Ullrich , Luxenburger Eva , Garcia Ronald , Irschik Herbert , Müller Rolf
Published: January 2017

Ripostatin is a promising antibiotic that inhibits RNA polymerase by binding to a novel binding site. In this study, the characterization of the biosynthetic gene cluster of ripostatin, which is a peculiar polyketide synthase (PKS) hybrid cluster encoding cis‐ and trans‐acyltransferase PKS genes, is reported. Moreover, an unprecedented mechanism for phenyl acetic acid formation and loading as a starter unit was discovered. This phenyl‐C2 unit is derived from phenylpyruvate (phenyl‐C3) and the mechanism described herein explains the mysterious loss of one carbon atom in ripostatin biosynthesis from the phenyl‐C3 precursor. Through in vitro reconstitution of the whole loading process, a pyruvate dehydrogenase like protein complex was revealed that performs thiamine pyrophosphate dependent decarboxylation of phenylpyruvate to form a phenylacetyl‐S‐acyl carrier protein species, which is supplied to the subsequent biosynthetic assembly line for chain extension to finally yield ripostatin.
Fully Copper‐Exchanged High‐Silica LTA Zeolites as Unrivaled Hydrothermally Stable NH3‐SCR Catalysts
Authors: Ryu Taekyung , Ahn Nak Ho , Seo Seungwan , Cho Jung , Kim Hyojun , Jo Donghui , Park Gi Tae , Kim Pyung Soon , Kim Chang Hwan , Bruce Elliott L. , Wright Paul A. , Nam In‐Sik , Hong Suk Bong
Published: January 2017

Diesel engine technology is still the most effective solution to meet tighter CO2 regulations in the mobility and transport sector. In implementation of fuel‐efficient diesel engines, the poor thermal durability of lean nitrogen oxides (NOx) aftertreatment systems remains as one major technical hurdle. Divalent copper ions when fully exchanged into high‐silica LTA zeolites are demonstrated to exhibit excellent activity maintenance for NOx reduction with NH3 under vehicle simulated conditions even after hydrothermal aging at 900 °C, a critical temperature that the current commercial Cu‐SSZ‐13 catalyst cannot overcome owing to thermal deactivation. Detailed structural characterizations confirm the presence of Cu2+ ions only at the center of single 6‐rings that act not only as a catalytically active center, but also as a dealumination suppressor. The overall results render the copper‐exchanged LTA zeolite attractive as a viable substitute for Cu‐SSZ‐13.
Enantiospecific Trifluoromethyl‐Radical‐Induced Three‐Component Coupling of Boronic Esters with Furans
Authors: Wang Yahui , Noble Adam , Sandford Christopher , Aggarwal Varinder K.
Published: January 2017

In the presence of trifluoromethylsulfonium reagents, boronate complexes derived from 2‐lithio furan and non‐racemic secondary and tertiary alkyl or aryl boronic esters undergo deborylative three‐component coupling to give the corresponding 2,5‐disubstituted furans with excellent levels of enantiospecificity. The process proceeds via the reaction of boronate complexes with a trifluoromethyl radical, which triggers 1,2‐metallate rearrangement upon single‐electron oxidation. Alternative electrophiles can also be used in place of trifluoromethylsulfonium reagents to effect similar three‐component coupling reactions.
Niche‐based species distribution models and conservation planning for endangered freshwater crayfish in south‐western Germany
Authors: Chucholl Christoph
Published: January 2017

Niche‐based species distribution models (SDMs) can help conservation planning by forecasting environmental suitability for an endangered species. Here, SDMs were constructed for stone crayfish (Austropotamobius torrentium) and white‐clawed crayfish (Austropotamobius pallipes s. str.) to identify catchments in south‐western Germany where environmental conditions are favourable for reintroduction.

Maximum‐entropy modelling (Maxent) was used with presence‐only data to forecast environmental suitability for the two crayfish species based on five climate variables, slope, land cover, and a human impact index.

SDMs showed good to excellent performance and were able to capture the range of both Austropotamobius species. Presence probabilities were mostly determined by climate variables, and climate niches partly overlap, with white‐clawed crayfish occurring at conditions with less extreme winter temperatures and lower temperature seasonality than stone crayfish. Human impact contributed between 10 and 27% to the models and was negatively related to presence probabilities. Contribution of land cover was low (5%) but showed a positive relationship with deciduous broadleaf forest in both species.

Both SDMs indicated several catchments with high predicted environmental suitability but no present occurrence records. Subsequent crayfish and habitat surveys in these catchments revealed four streams considered suitable for reintroduction and led to discovery of five previously unknown white‐clawed crayfish populations. Overall, SDMs proved to be a powerful tool for conservation planning of freshwater crayfish species.
Schlank und elegant – Stahlbogenbrücke über die A 8 bei Stuttgart
Authors: Keil Andreas , Schächner Frank
Published: January 2017

Die stark befahrene A 8 wird zwischen dem Kreuz Stuttgart und der Anschlussstelle Leonberg/Ost um einen Fahrstreifen erweitert. Aufgrund des zu geringen Lichtraumprofils wurde die bestehende Bogenbrücke „Rotes Steigle”, die einen Forstweg über die Autobahn überführt, abgebrochen und durch einen markanten Neubau ersetzt. Das Tragwerk der neuen, ca. 75 m langen Verbundbrücke besteht aus einem unten liegenden Stahlbogen mit veränderlichen Querschnitten, schräg nach außen geneigten Stahlstreben und einer Stahlbetonfahrbahnplatte. Das schlanke Bogentragwerk ist als 2‐Gelenk‐Bogen ausgeführt und ruht auf Edelstahl‐Kippleisten. Der Überbau stützt sich mit dünnen, geneigten Streben auf dem Bogen ab und ist mit den Widerlagern über je ein etwa 1,10 m hohes und nur 2 cm dickes Stahlblech, einer sogenannten „Federlamelle”, monolithisch angeschlossen.

Bei der Herstellung des Stahltragwerks wurden die einzelnen Stahlbauteile zu zwei großen, ca. 40 m langen und 120 t schweren Bogenhälften auf dem nahe gelegenen Vormontageplatz verschweißt, sodass für den Einhub lediglich zwei nächtliche Vollsperrungen der A 8 erforderlich waren. Das Betonieren der Fahrbahnplatte erfolgte mit einem verfahrbaren Schalwagen in fünf Betonierabschnitten unter fließendem Verkehr. Durch abschnittsweise Herstellung des Stahl‐ und Betonbaus waren aufwändige Verformungsberechnungen bzw. Überhöhungsberechnungen für die Fertigung und die Bauausführung erforderlich.

Als moderner Kontrast zur vorherigen Brücke ist so eine filigrane Stahlbogenbrücke entstanden.
Cooperative learning in Forestry Engineering with NIPPE Descartes software
Authors: Grande‐Ortiz María A. , Tevar‐Sanz Gonzalo , Ayuga‐Téllez Esperanza , González‐García Concepción , Sánchez‐De Medina Álvaro , Ramírez‐Montoro Juan José
Published: January 2017

This work describes the methodology, procedure, and results obtained from the application of an education co‐operative learning experience with NIPPE Descartes software in a specific task. Students in the second year of a degree course in Forestry Engineering at the Madrid Polytechnic University were invited to take part in a peer‐learning experience. The students were organized in pairs and asked to complete an optional task in one of the modules in the subject of Mechanics. This experience took place between 2006 and 2011. The results were compared with the previous period between 2003 and 2006 in which this task was not required. The students were surveyed to assess their degree of satisfaction and the contribution of the experience to the learning of the subject. This methodology was observed to substantially reduce the percentage of students who do not show up for their evaluation exams, and the percentage of pass and fail marks also reveals significant differences. Additionally, of the students who performed the task, the number who passed in the ordinary examination period increased nearly 30% points compared to those who did not. It is worth noting that 43% of the students participating in the experience rated the activity as a fairly or very positive in terms of contributing to learning the subject. © 2017 Wiley Periodicals, Inc. Comput Appl Eng Educ 25:103–111, 2017; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21783