bluuebunny/crossref_metadata_2025_split huggingface dataset:
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.
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.
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

AbstractNo Abstractmagnified image
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

AbstractAn 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.magnified image
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

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

AbstractBecause 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.magnified image
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

AbstractA 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.magnified image
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

AbstractSeveral 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.magnified image
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

AbstractPhenylene‐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.magnified image
“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

AbstractIridium(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.magnified image
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 HIGHLIGHTSValidation 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

AbstractNitrobenzothiazinone 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

AbstractRipostatin 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

AbstractEin 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

AbstractThe 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

AbstractColloids 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

AbstractNitrobenzothiazinones 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

AbstractRipostatin 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.