bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zeferino e o problema da seca no Nordeste
Authors: Mourilhe Fabio 
Published: February 2017

O objetivo deste trabalho é verificar como os problemas relacionados à caatinga no Nordeste seco, na década de 1970, são tratados nas tiras do Zeferino de Henfil, publicadas na revista Fradim. Para atingir tal intento, traçamos inicialmente um panorama do local, considerando os aspectos culturais, físicos, ecológicos e sociais. O humor de Henfil serve para apontar os problemas ali vigentes e direcionar esta percepção para uma atitude crítica. Não apresenta exatamente uma solução, mas uma exacerbação do problema para que ele possa ser utilizado fora do contexto em metáforas e através de um humor que emerge com a criação de caricaturas da realidade, tornando-a menos insuportável. Palavras-chave: Seca, Henfil, quadrinhos
Comida e visualidade
Authors: Azevedo Elaine De , Peled Shay 
Published: February 2017

Este estudo teórico-conceitual coloca em evidência temas e debates ligados à alimentação sob uma perspectiva sociopolítica e cultural, a partir de diferentes mídias audiovisuais – cinema, TV, reality shows e vídeos veiculados na internet. O artigo se debruça particularmente sobre filmes no cinema que mobilizam a alimentação como eixo transversal das tramas. A ideia é complexificar a comida como temática audiovisual e pensá-la como estratégia sensorial. Palavras-chave: Alimentação, cinema, visualidade
Definice, příčiny a důsledky kumulace mandátů zákonodárci
Authors: Hájek Lukáš 
Published: February 2017

The article deals with various aspects of multiple-office holding. Although the phenomenon is especially influential in connection with legislators, the text offers a critical synthesis of recent findings on multiple-office holding on any level of political decision-making, thus providing a general framework for scholarly discussion and further research. The paper first provides a definition of the concept of multiple-office holding, which has been heretofore lacking in the Czech context. Causes of multiple-office holding are then delineated and divided into the three categories of historical reverberations, systemic elements and individual incentives. Both the positive and negative impacts on a political system are discussed as well. Next, three approaches (direct, indirect, and autoregulatory) of dealing with the practice of multiple-office holding, which are employed by particular political systems, are distinguished. Then, the role of a multiple-office holding in the Czech political system is depicted. The final part of the paper discusses a specific controversy linked to the phenomenon and criticises the lack of proper debates and scientific analyses on the practice.
Obraz první Československé republiky při projednávání Ústavy ČR
Authors: Marková Klára 
Published: February 2017

This paper focuses on the image of the political system of the first Czechoslovak Republic in the political discourse connected with the preparation of the Czech Constitution in 1992. It works mainly with records of parliamentary debates between July and December 1992 and considers three types of actors: members of committees working on the constitution, constitutional lawyers and political figures with a significant informal influence, such as Václav Havel. The author asks three interrelated research questions: How was the first Czechoslovak Republic portrayed in the debates on the Czech Constitution? In what context of the discussions and argumentations did the First republic reappear? And what role did the image of the Czechoslovak Republic play in the debates? As I argue, the system of the first Czechoslovak Republic was presented almost always positively, framed by concepts of tradition, democracy, sovereignty, and stability. Conversely, the Senate was portrayed more negatively, as a symbol of inefficiency, futility and expensiveness. The political system of the First Republic and the Constitution of 1920 represented an issue that could not be ignored and had to emerge through discourse. Some speakers did not always portray it properly and rarely spoke about the problematic aspects of the functioning of the political system of the First Republic. However, it was always alluded to as a symbol whose meaning was often more important than its actual content, as it could confirm the legitimacy of power relationships and express identification with a given political line. The fact that the actors chose only certain images of the First Republic, mostly the positive ones, illustrates that they sought to use the power of the symbol of the First Republic.
Spawning aggregation of white-streaked grouperEpinephelus ongus: spatial distribution and annual variation in the fish density within a spawning ground
Authors: Nanami Atsushi , Sato Taku , Kawabata Yuuki , Okuyama Junichi 
Published: February 2017

White-streaked grouper (Epinephelus ongus) is an important fisheries target and forms spawning aggregations at particular spawning grounds. The aims of the present study were to investigate the ecological characteristics of annual spawning aggregations such as (1) spatial variations in the density ofE. ongusat the spawning ground, (2) the relationship between fish density and environmental variables, (3) inter-annual variations in the spawning aggregation, (4) the proportion of males to females at the spawning ground for several days pre—and post-spawning and (5) the relationship between male density and female density at the protected spawning ground, based on observations over five years at an Okinawan coral reef. Although the protected spawning ground area was large (ca. 2,500 m × 700 m), high density ofE. ongus(over 25 individuals per 100 m2) was found in a limited area (within c.a. 750 m × 50 m). Current velocity and coverage of rocks had significant positive effects on the spatial distribution ofE. ongusat the spawning ground. Inter-annual variation in the degree of aggregation was found and this variation was explained by the annual variation of mean seawater temperature during 40 days before the spawning day. The male–female ratio (male:female) at the spawning ground was ca. 3:1 for three years (May 2012, May 2014 and May 2015) whereas >13:1 for one year (May 2013). Significant positive relationships between male density and female density were found at the aggregation sites. It is suggested thatE. ongususe aggregation sites with greater current velocity to reduce the risk of egg predation and seawater temperature is one of the main factors that is responsible for determining the degree of aggregation. It is also suggested that females possibly select sites with a greater density of males and this selection behavior might be the reason why females arrived at the spawning ground after the arrival of the males. For effective management of spawning grounds, precise site selection as well as the duration of the protection period are suggested to be key aspects to protect the spawning aggregations ofE. ongus, which have been currently achieved at the spawning ground.
Detection of increased heating and estimation of coseismic shear stress from Raman spectra of carbonaceous material in pseudotachylytes
Authors: Ito Keisuke , Ujiie Kohtaro , Kagi Hiroyuki 
Published: February 2017

AbstractFrictional heat generated during earthquakes provides insight into the coseismic fault strength. To detect increased heating associated with faulting at seismic slip rates, we analyzed the Raman spectra of carbonaceous material in natural and experimental pseudotachylytes derived from argillite. The results indicate that the increased carbonization in pseudotachylytes relative to the host rocks could be detected when the ambient temperature is lower than 280°C. This increased carbonization can occur in ~4–16 s and is preserved even after alteration of pseudotachylytes. The comparison between experiment and Raman data demonstrated that there is a correlation between the average shear stress and the Raman spectra in pseudotachylytes. The average coseismic shear stress estimated from the correlation was 1.8 MPa. The resulting apparent friction coefficient under hydrostatic conditions at depths of 4–6 km was ~0.03–0.05. Raman analysis of carbonaceous material‐bearing pseudotachylytes will be useful for estimation of coseismic fault strength.
An increased abundance of micrometeorites on Earth owing to vesicular parachutes
Authors: Genge Matthew J. 
Published: February 2017

AbstractMicrometeorites (MMs) are extraterrestrial dust particles that survive atmospheric entry and can be recovered from sedimentary rocks. Fossil MMs allow events beyond the Earth, such as the collisional breakup of asteroids, to be identified. Here the effects of vesicle formation during melting of dust are investigated through numerical modeling and observations of Antarctic MMs. Vesicle formation is shown to cause a parachute effect that causes rapid deceleration, decreasing peak temperature. Vesicular parachuting enhances the abundance of melted MMs formed from phyllosilicate‐bearing C‐type asteroid dust on the Earth surface by a factor of 2. Micrometeorites recovered from the geological record, therefore, are biased toward breakup events involving hydrated C‐type asteroids, whilst those involving phyllosilicate‐poor particles are diluted by the enhanced background flux of hydrous dust. The parachute effect is also likely to increase the delivery of 3He to ocean sediments by C‐type asteroid dust.
CO2‐to‐Methanol Hydrogenation on Zirconia‐Supported Copper Nanoparticles: Reaction Intermediates and the Role of the Metal–Support Interface
Authors: Larmier Kim , Liao Wei‐Chih , Tada Shohei , Lam Erwin , Verel René , Bansode Atul , Urakawa Atsushi , Comas‐Vives Aleix , Copéret Christophe 
Published: February 2017

AbstractMethanol synthesis by CO2 hydrogenation is a key process in a methanol‐based economy. This reaction is catalyzed by supported copper nanoparticles and displays strong support or promoter effects. Zirconia is known to enhance both the methanol production rate and the selectivity. Nevertheless, the origin of this observation and the reaction mechanisms associated with the conversion of CO2 to methanol still remain unknown. A mechanistic study of the hydrogenation of CO2 on Cu/ZrO2 is presented. Using kinetics, in situ IR and NMR spectroscopies, and isotopic labeling strategies, surface intermediates evolved during CO2 hydrogenation were observed at different pressures. Combined with DFT calculations, it is shown that a formate species is the reaction intermediate and that the zirconia/copper interface is crucial for the conversion of this intermediate to methanol.
Hollow Iron–Vanadium Composite Spheres: A Highly Efficient Iron‐Based Water Oxidation Electrocatalyst without the Need for Nickel or Cobalt
Authors: Fan Ke , Ji Yongfei , Zou Haiyuan , Zhang Jinfeng , Zhu Bicheng , Chen Hong , Daniel Quentin , Luo Yi , Yu Jiaguo , Sun Licheng 
Published: February 2017

AbstractNoble‐metal‐free bimetal‐based electrocatalysts have shown high efficiency for water oxidation. Ni and/or Co in these electrocatalysts are essential to provide a conductive, high‐surface area and a chemically stable host. However, the necessity of Ni or Co limits the scope of low‐cost electrocatalysts. Herein, we report a hierarchical hollow FeV composite, which is Ni‐ and Co‐free and highly efficient for electrocatalytic water oxidation with low overpotential 390 mV (10 mA cm−2 catalytic current density), low Tafel slope of 36.7 mV dec−1, and a considerable durability. This work provides a novel and efficient catalyst, and greatly expands the scope of low‐cost Fe‐based electrocatalysts for water splitting without need of Ni or Co.
A Ruthenium Complex–Porphyrin–Fullerene‐Linked Molecular Pentad as an Integrative Photosynthetic Model
Authors: Yamamoto Masanori , Föhlinger Jens , Petersson Jonas , Hammarström Leif , Imahori Hiroshi 
Published: February 2017

AbstractA ruthenium complex, porphyrin sensitizer, fullerene acceptor molecular pentad has been synthesized and a long‐lived hole–electron pair was achieved in aqueous solution by photoinduced multistep electron transfer: Upon irradiation by visible light, the excited‐state of a zinc porphyrin (1ZnP*) was quenched by fullerene (C60) to afford a radical ion pair, 1,3(ZnP.+‐C60.−). This was followed by the subsequent electron transfer from a water oxidation catalyst unit (RuII) to ZnP.+ to give the long‐lived charge‐separated state, RuIII‐ZnP‐C60.−, with a lifetime of 14 μs. The ZnP worked as a visible‐light‐harvesting antenna, while the C60 acted as an excellent electron acceptor. As a consequence, visible‐light‐driven water oxidation by this integrated photosynthetic model compound was achieved in the presence of sacrificial oxidant and redox mediator.
(Ge4Bi14)4−: A Case of “Element Segregation” on the Molecular Level
Authors: Wilson Robert J. , Dehnen Stefanie 
Published: February 2017

AbstractExtraction of a solid with the nominal composition “K2GeBi” with 1,2‐diaminoethane (en) in the presence of 4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane (crypt‐222) afforded the salt [K(crypt‐222)]4(Ge4Bi14). The 18‐atom Zintl anion (Ge4Bi14)4− has a heretofore unknown molecular topology, which can be thought of as the formal condensation product of two E113− cages along a shared Ge4 waist. In this way, (Ge4Bi14)4− represents the largest and most structurally complex Bi‐containing polyanion. We describe its stepwise formation, its geometric and electronic structure, and comment on relative stabilities of isomers with different distributions of the four Ge atoms on the 18 positions that were investigated using DFT calculations.
Binuclear, High‐Valent Nickel Complexes: Ni−Ni Bonds in Aryl–Halogen Bond Formation
Authors: Diccianni Justin B. , Hu Chunhua , Diao Tianning 
Published: February 2017

AbstractMetal–metal bonds play a vital role in stabilizing key intermediates in bond‐formation reactions. We report that binuclear benzo[h]quinoline‐ligated NiII complexes, upon oxidation, undergo reductive elimination to form carbon–halogen bonds. A mixed‐valent Ni(2.5+)–Ni(2.5+) intermediate is isolated. Further oxidation to NiIII, however, is required to trigger reductive elimination. The binuclear NiIII–NiIII intermediate lacks a Ni−Ni bond. Each NiIII undergoes separate, but fast reductive elimination, giving rise to NiI species. The reactivity of these binuclear Ni complexes highlights the fundamental difference between Ni and Pd in mediating bond‐formation processes.
An Unconventional Mechanistic Insight into SCF3 Formation from Difluorocarbene: Preparation of 18F‐Labeled α‐SCF3 Carbonyl Compounds
Authors: Zheng Jian , Cheng Ran , Lin Jin‐Hong , Yu Dong‐Hai , Ma Longle , Jia Lina , Zhang Lan , Wang Lu , Xiao Ji‐Chang , Liang Steven H. 
Published: February 2017

AbstractTrifluoromethylthiolation by sulfuration of difluorocarbene with elemental sulfur is described for the first time, which overrides long‐standing trifluoromethyl anion‐based theory. Mechanistic elucidation reveals an unprecedented chemical process for the formation of thiocarbonyl fluoride and also enables transition‐metal‐mediated trifluoromethylthiolation and [18F]trifluoromethylthiolation of α‐bromo carbonyl compounds with broad substrate scope and compatibility.
Enhancement of C−H Oxidizing Ability in Co–O2 Complexes through an Isolated Heterobimetallic Oxo Intermediate
Authors: DeRosha Daniel E. , Mercado Brandon Q. , Lukat‐Rodgers Gudrun , Rodgers Kenton R. , Holland Patrick L. 
Published: February 2017

AbstractThe characterization of intermediates formed through the reaction of transition‐metal complexes with dioxygen (O2) is important for understanding oxidation in biological and synthetic processes. Here, the reaction of the diketiminate‐supported cobalt(I) complex LtBuCo with O2 gives a rare example of a side‐on dioxygen complex of cobalt. Structural, spectroscopic, and computational data are most consistent with its assignment as a cobalt(III)–peroxo complex. Treatment of LtBuCo(O2) with low‐valent Fe and Co diketiminate complexes affords isolable oxo species with M2O2 “diamond” cores, including the first example of a crystallographically characterized heterobimetallic bis(μ‐oxo) complex of two transition metals. The bimetallic species are capable of cleaving C−H bonds in the supporting ligands, and kinetic studies show that the Fe/Co heterobimetallic species activates C−H bonds much more rapidly than the Co/Co homobimetallic analogue. Thus heterobimetallic oxo intermediates provide a promising route for enhancing the rates of oxidation reactions.
Steering Siglec–Sialic Acid Interactions on Living Cells using Bioorthogonal Chemistry
Authors: Büll Christian , Heise Torben , van Hilten Niek , Pijnenborg Johan F. A. , Bloemendal Victor R. L. J. , Gerrits Lotte , Kers‐Rebel Esther D. , Ritschel Tina , den Brok Martijn H. , Adema Gosse J. , Boltje Thomas J. 
Published: February 2017

AbstractSialic acid sugars that terminate cell‐surface glycans form the ligands for the sialic acid binding immunoglobulin‐like lectin (Siglec) family, which are immunomodulatory receptors expressed by immune cells. Interactions between sialic acid and Siglecs regulate the immune system, and aberrations contribute to pathologies like autoimmunity and cancer. Sialic acid/Siglec interactions between living cells are difficult to study owing to a lack of specific tools. Here, we report a glycoengineering approach to remodel the sialic acids of living cells and their binding to Siglecs. Using bioorthogonal chemistry, a library of cells with more than sixty different sialic acid modifications was generated that showed dramatically increased binding toward the different Siglec family members. Rational design reduced cross‐reactivity and led to the discovery of three selective Siglec‐5/14 ligands. Furthermore, glycoengineered cells carrying sialic acid ligands for Siglec‐3 dampened the activation of Siglec‐3+ monocytic cells through the NF‐κB and IRF pathways.
A General and Highly Selective Cobalt‐Catalyzed Hydrogenation of N‐Heteroarenes under Mild Reaction Conditions
Authors: Adam Rosa , Cabrero‐Antonino Jose R. , Spannenberg Anke , Junge Kathrin , Jackstell Ralf , Beller Matthias 
Published: February 2017

AbstractHerein, a general and efficient method for the homogeneous cobalt‐catalyzed hydrogenation of N‐heterocycles, under mild reaction conditions, is reported. Key to success is the use of the tetradentate ligand tris(2‐(diphenylphosphino)phenyl)phosphine). This non‐noble metal catalyst system allows the selective hydrogenation of heteroarenes in the presence of a broad range of other sensitive reducible groups.
Experimental and numerical investigations of the interlaminar shear properties of carbon/carbon composites
Authors: Li Xin , Yan Ying , Tan Yongyang , Guo Fangliang , Hong Yang , Tian Ziyang 
Published: February 2017

ABSTRACTExperimental tests and numerical simulations were implemented to investigate the interlaminar shear properties of carbon/carbon composites (C/Cs). A unit‐cell model, according to the microstructure of the C/Cs, was used to predict material properties of the C/Cs. A three‐dimensional finite element model was established to investigate the damage behavior of C/Cs on the basis of Linde failure criterion and damage evolution. Good agreement, in terms of the load force history and failure modes, was observed between the experimental and numerical results; this provided the applicability of the numerical simulation. The test results show that the interlaminar shear strength of the C/Cs was 10.52 MPa and the value of the simulation result was 10.89 MPa, with the relative error being less than 4%. Damage contours and stress distribution analysis of the simulation results are discussed. Fiber damage occurred at the bottom of the specimen, and matrix damage was found in the upper half of the specimen; this was similar to the appearance of the tested specimens. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44783.
Thermally induced double‐positive temperature coefficients of electrical resistivity in combined conductive filler–doped polymer composites
Authors: Hou Yan‐ling , Zhang Peng , Xie Miao‐miao 
Published: February 2017

ABSTRACTPolymer composites of low‐density polyethylene/polypropylene/graphite/vanadium dioxide (LDPE0.8/PP0.2/Gr0.4/VO2) are prepared by classical melt‐mixing technology and show a notable double positive temperature coefficient of electric resistivity (PTC), which originates from the combined effect of highly conductive Gr and VO2 with a thermal phase transition. When the weight ratio of VO2 is 8 wt %, the positive temperature coefficient intensity (PTCI) for the composites reaches 3.85 orders of magnitude. The model system demonstrates the reason for the improvement in the PTC performance of the polymer composites by analyzing the construction of the conductive networks. Therefore, the addition of phase‐transition compounds may be a promising path to improving PTC materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44876.
Antibacterial N‐halamine coating on cotton fabric fabricated using mist polymerization
Authors: Luo Guangyan , Xi Guanghui , Wang Xiyi , Qin Dandan , Zhang Yanyan , Fu Feiya , Liu Xiangdong 
Published: February 2017

ABSTRACT3‐Methylallyloxy‐5,5‐dimethylhydantoin (MH), an methacrylate monomer containing N‐halamine moiety, was synthesized by 5,5‐dimethylhydantoin (DMH) and methacryloyl chloride. Antimicrobial coating of poly[1‐methyl‐1‐(4,4‐dimethyl‐2,5‐dioxoimidazolidin‐carbonyl)ethylene] (PMH) was prepared on cotton fabrics via “mist polymerization” using MH as monomer. The coating gave the cotton fabric with efficient antibacterial function with remarkable durability. In the antibacterial tests, the bacteriostatic reduction rate is greater than 99.78%, and can be maintained over 99.00% even after 30 washing cycles. Compared with other antimicrobial technologies, mist polymerization offers advantages such as achieving antimicrobial function by small consumption of monomer, forming coatings on single‐side of the fabrics, and minimizing the damages on the original properties of cotton during the finishing process. It can be applied in a wide variety of textile products such as sportswear, underwear, socks, and medical textiles. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44897.