bluuebunny/crossref_metadata_2025_split huggingface dataset:
A multi-approach and multi-scale study on water quantity and quality changes in the Tapajós River basin, Amazon
Authors: Nóbrega Rodolfo Luiz Bezerra , Lamparter Gabriele , Hughes Harold , Guzha Alphonce Chenjerayi , Amorim Ricardo Santos Silva , Gerold Gerhard 
Published: April 2018

Abstract. We analyzed changes in water quantity and quality at different spatial scales
within the Tapajós River basin (Amazon) based on experimental fieldwork,
hydrological modelling, and statistical time-trend analysis. At a small
scale, we compared the river discharge (Q) and suspended-sediment
concentrations (SSC) of two adjacent micro-catchments (< 1 km2)
with similar characteristics but contrasting land uses
(forest vs. pasture) using empirical data from field measurements. At an
intermediary scale, we simulated the hydrological responses of a sub-basin of
the Tapajós (Jamanxim River basin, 37 400 km2), using a hydrological
model (SWAT) and land-use change scenario in order to quantify the changes in
the water balance components due to deforestation. At the Tapajós' River
basin scale, we investigated trends in Q, sediments, hydrochemistry, and
geochemistry in the river using available data from the HYBAM Observation
Service. The results in the micro-catchments showed a higher runoff
coefficient in the pasture (0.67) than in the forest catchment (0.28). At
this scale, the SSC were also significantly greater during stormflows in the
pasture than in the forest catchment. At the Jamanxim watershed scale, the
hydrological modelling results showed a 2 % increase in Q and a 5 %
reduction of baseflow contribution to total Q after a conversion of 22 %
of forest to pasture. In the Tapajós River, however, trend analysis did
not show any significant trend in discharge and sediment concentration.
However, we found upward trends in dissolved organic carbon and NO3-
over the last 20 years. Although the magnitude of anthropogenic impact has
shown be scale-dependent, we were able to find changes in the Tapajós
River basin in streamflow, sediment concentration, and water quality across
all studied scales.
Morphodynamic change analysis of bedforms in the Lower Orinoco River, Venezuela
Authors: Yepez Santiago Paul , Laraque Alain , Gualtieri Carlo , Christophoul Frédéric , Marchan Claudio , Castellanos Bartolo , Azocar Jose Manuel , Lopez Jose Luis , Alfonso Juan 
Published: April 2018

Abstract. The Orinoco River has the third largest discharge in the world, with an
annual mean flow of 37 600 m3 s−1 at its outlet to the Atlantic
Ocean. Due to the presence of the Guiana Shield on the right bank, the lower
reach of the Orinoco has a plan form characterized by contraction and
expansion zones. Typical 1–1.5 km wide narrow reaches are followed by
7–8 km
wide reaches. A complex pattern of bed aggradation and degradation processes
takes place during the annual hydrological regime. A series of Acoustic
Doppler Current Profiler (ADCP) transects were collected on an expansion
channel in the Orinoco River, specifically over a fluvial island,
representative of the lower Orinoco. In this study, temporal series of
bathymetric cartography obtained by ADCP profiles combined with Differential
Global Position System (DGPS) measurements (with dual-frequency), were used
to recover the local displacement of bed forms in this island. The principal
aims of this analysis were: (1) to understand the dynamics and evolution of
sand waves and bars at this section and (2) to quantify the volume (erosion
vs. accretion) of a mid-channel bar with dunes by applying DEM of
Difference (DoD) maps on time series of bathymetric data. This required
sampling with ADCP transects during the months of: May 2016; November 2016
and April 2017. Each bathymetric transect was measured twice, 1 day apart
and on the same trajectory obtained by a GPS receptor. The spatial analysis
of these ADCP transects is presented as a novel tool in the acquisition of
time series of bathymetry for a relatively deep section (∼20 m) and under variable flow conditions.
Eficacia de la política contra la pobreza en la UE. Evaluación con el "Fuzzy Pverty Indicator" (FPI)
Authors: Francisco J. Sánchez-Vellvé  
Published: April 2018

En este trabajo se evalúa la consecución de los objetivos de pobreza de la Estrategia 2020. Para ello se construye, por primera vez para el conjunto de los Estados miembros de la UE, una medida alternativa de pobreza monetaria a partir de la metodología de los conjuntos difusos, que permite evitar algunos de los inconvenientes del indicador AROPE.
Los resultados con el Fuzzy Poverty Indicator (FPI) indican que la probabilidad de que un ciudadano sea pobre en la UE se ha incrementado ligeramente desde la puesta en marcha del programa en poco más de 20 puntos básicos. La UE no está consiguiendo los beneficios pretendidos y, además, da muestras de una importante ausencia de coordinación debida a la falta de homogeneidad en los objetivos y a un comportamiento dispar entre los Estados miembros.
A new lineage of Cretaceous jewel wasps (Chalcidoidea: Diversinitidae)
Authors: Haas Michael , Burks Roger A. , Krogmann Lars 
Published: April 2018

Jewel wasps (Hymenoptera: Chalcidoidea) are extremely species-rich today, but have a sparse fossil record from the Cretaceous, the period of their early diversification. Three genera and three species,Diversinitus attenboroughigen. & sp. n., Burminata caputaeriagen. & sp. n. andGlabiala barbatagen. & sp. n. are described in the family Diversinitidae fam. n., from Lower Cretaceous Burmese amber. Placement in Chalcidoidea is supported by the presence of multiporous plate sensilla on the antennal flagellum and a laterally exposed prepectus. The new taxa can be excluded from all extant family level chalcidoid lineages by the presence of multiporous plate sensilla on the first flagellomere in both sexes and lack of any synapomorphies. Accordingly, a new family is proposed for the fossils and its probable phylogenetic position within Chalcidoidea is discussed. Morphological cladistic analyses of the new fossils within the Heraty et al. (2013) dataset did not resolve the phylogenetic placement of Diversinitidae, but indicated its monophyly. Phylogenetically relevant morphological characters of the new fossils are discussed with reference to Cretaceous and extant chalcidoid taxa. Along with mymarid fossils and a few species of uncertain phylogenetic placement, the newly described members of Diversinitidae are among the earliest known chalcidoids and advance our knowledge of their Cretaceous diversity.
ДЕНДРИТНЫЕ ПОЛИЭЛЕКТРОЛИТНЫЕ ЩЕТКИ1, "Высокомолекулярные соединения. Серия С"
Authors: Жулина E. Б. , Борисов О.В. 
Published: April 2018

Рассмотрено современное состояние теории щеток, образованных дендритно-разветвленными заряженными макромолекулами, прикрепленными корневым сегментом к плоской поверхности и погруженными в полярный растворитель (воду). Теория позволяет раскрыть наиболее специфические свойства таких щеток, связанные с разветвленной архитектурой составляющих их макромолекул, и систематически сравнить их со свойствами щеток, образованных линейными полиэлектролитными цепями. Благодаря своим особым свойствам дендритные полиэлектролитные щетки являются перспективными для создания “умных” функциональных полимерных материалов.
Câncer de mama triplo negativo e sua associação com ancestralidade africana
Authors: Corrêa Paula Brito , Toralles Maria Bethânia Pereira , Abe-Sandes Kiyoko , Machado Taisa Manuela Bonfim , Bonfim Thaís Ferreira , Meyer Lorena , Abe-Sandes Camila , Nascimento Ivana 
Published: April 2018

<div>Câncer de mama triplo-negativo (TN) é um termo recente e refere-se a tumores que, quando analisados por imunohistoquímica, não expressam receptores de estrógeno, progesterona e HER2 (receptor do fator de crescimento epidérmico). O fenótipo triplo-negativo possui características patológicas e clínicas bastante diferentes dos demais subtipos de câncer de mama. Estes tumores afetam mais frequentemente mulheres com menos de 50 anos, que possuem comportamento mais agressivo, apresentam resposta pobre aos protocolos de tratamento existentes e são mais prevalentes entre as afrodescendentes (AD). O objetivo deste estudo foi fazer uma associação fenotípica entre ancestralidade africana e câncer de mama triplo-negativo. Foram analisados 70 prontuários de pacientes encaminhados ao Ambulatório de Oncogenética do Complexo do Hospital Universitário Professor Edgar Santos da Universidade Federal da Bahia, dos quais 14,2% apresentaram o fenótipo TN. No fenótipo triplo-negativo, as afrodescendentes apresentaram frequência maior, 10%, quando comparadas com mulheres do grupo racial branco. Estudos moleculares são necessários para explicar essas diferenças raciais. Tais associações podem contribuir para o desenvolvimento de uma nova estratégia terapêutica em mulheres AD com esse fenótipo.</div>
Avanços e aplicações da bioengenharia tecidual
Authors: Oliveira Conceição Silva , Nascimento Marion , De Almeida Junior Erasmo , Crusoé Mady , Bahia Poliana , Rosa Fabiana Paim 
Published: April 2018

<div>A bioengenharia compila conhecimentos de grandes áreas da ciência, como a biologia e a engenharia, que são aplicados </div><div>atualmente na medicina reparadora. Recentes avanços na área da engenharia tecidual possibilitaram o desenvolvimento e aperfeiçoamento de novos biomateriais. Estes devem estimular a adesão, diferenciação e proliferação celular, e ainda promover a produção de moléculas específicas do tecido-alvo. As células usadas na terapia podem ser mesenquimais de medula óssea, células adultas específicas do próprio paciente e também as células-tronco embrionárias, as quais têm capacidade de se diferenciar em múltiplas linhagens in vitro. As células-tronco têm sido empregadas em diversas áreas da saúde. Células mesenquimais e polpa dental são fontes de células-tronco que podem se diferenciar em fibroblastos, cementoblastos e osteoblastos. Para que ocorra tal diferenciação, são necessários alguns sinais para direcionar as etapas do desenvolvimento e da regeneração tecidual. Um dos grandes desafios da engenharia tecidual é desvendar esses sinais e etapas para tentar entender as sinalizações necessárias à reprodução do tecido. Os avanços das pesquisas com células-tronco e a bioengenharia tecidual</div><div>abrem oportunidades para desenvolver novas terapias, como a terapia gênica e os estudos relacionados com a angiogênese. Hoje em dia, sabe-se que as células-tronco adultas estão presentes nos vasos sanguíneos, no pâncreas, no fígado, no cérebro, na polpa dentária, entre outros tecidos, mas são as células da medula óssea as mais estudadas no contexto de muitas doenças, especialmente as cardiovasculares. Depois das células-tronco embrionárias, o tratamento biológico mais questionado é a terapia gênica. Para corrigir defeitos genéticos, é preciso inserir genes na célula que, na maioria das vezes, são introduzidos por meio de vírus. Este artigo tem como escopo abordar a atuação das células-tronco, a angiogênese, a terapia gênica na bioengenharia tecidual e a interação celular associada aos biomateriais.</div>
Preliminary Results From the Latin American Giant Observatory Space Weather Simulation Chain
Authors: Asorey Hernan , Núñez Luis A. , Suárez‐Durán Mauricio 
Published: April 2018

AbstractThe Space Weather program of the Latin American Giant Observatory (LAGO) Collaboration was designed to study the variation of the flux of atmospheric secondary particles at ground level produced during the interaction of cosmic rays with the air. This work complements and expands the inference capabilities of the LAGO detection network to identify the influence of solar activity on the particle flux, at places having different geomagnetic rigidity cut‐offs and atmospheric depths. This program is developed through a series of Monte Carlo sequential simulations to compute the intensity spectrum of the various components of the radiation field on the ground. A key feature of these calculations is that we performed detailed radiation transport computations as a function of incident direction, time, altitude, and latitude and longitude. Magnetic rigidity calculations and corrections for geomagnetic field activity are established by using the MAGNETOCOSMICS code, and the estimation of the flux of secondaries at ground level is implemented by using the CORSIKA code; thus, we can examine the local peculiarities in the penumbral regions with a more realistic description of the atmospheric and geomagnetic response in these complex regions of the rigidity space. As an example of our calculation scheme, we report some result on the flux at ground level for two LAGO locations: Bucaramanga, Colombia, and San Carlos de Bariloche, Argentina, for the geomagnetically active period of May 2005.
Perioperative analgesia for patients undergoing endoscopic sinus surgery: an evidence‐based review
Authors: Svider Peter F. , Nguyen Brandon , Yuhan Brian , Zuliani Giancarlo , Eloy Jean Anderson , Folbe Adam J. 
Published: April 2018

BackgroundMisuse and diversion of prescription opioids have been critical in facilitating the opioid epidemic. Our objective was to perform a systematic evidence‐based review delineating perioperative regimens (including opioid alternatives) evaluated for endoscopic sinus surgery.MethodsPubMed/MEDLINE, Cochrane Library, and EmBase databases were evaluated for studies detailing analgesics employed after endoscopic sinus surgery. Studies were assessed for level of evidence. Bias risk was evaluated using the Cochrane Bias tool and GRADE criteria. Medication, administration, adverse effects, pain scores, and rescue analgesic consumption were evaluated. A summary of evidence detailing benefits, harm, and cost was prepared.ResultsThirty‐two studies encompassing 1812 patients were included. The GRADE criteria determined the overall evidence to be of moderate quality. Perioperative acetaminophen had few adverse events and reduced immediate need for opioid rescue after sinus surgery; studies evaluating acetaminophen demonstrate a preponderance of benefit over harm. Nonsteroidal anti‐inflammatory drugs (NSAIDs) also reduce postoperative opioid consumption, although a small portion of patients undergoing sinus surgery harbor the potential for NSAID intolerance. The aggregate level of evidence for studies evaluating NSAIDs was grade A, whereas the aggregate grade of evidence for several other agents was grade B.ConclusionThere is evidence supporting the use of NSAIDs and gabapentin for the control of pain after endoscopic sinus surgery. Acetaminophen, α‐agonists, and local anesthetics are also viable options for postoperative analgesia. Familiarity with these data is essential to facilitate the use of opioid alternatives. Further large‐scale, multi‐institutional, randomized trials are needed to provide conclusive recommendations for these perioperative analgesics.
Complexing DNA Origami Frameworks through Sequential Self‐Assembly Based on Directed Docking
Authors: Suzuki Yuki , Sugiyama Hiroshi , Endo Masayuki 
Published: April 2018

AbstractOrdered DNA origami arrays have the potential to compartmentalize space into distinct periodic domains that can incorporate a variety of nanoscale objects. Herein, we used the cavities of a preassembled 2D DNA origami framework to incorporate square‐shaped DNA origami structures (SQ‐origamis). The framework was self‐assembled on a lipid bilayer membrane from cross‐shaped DNA origami structures (CR‐origamis) and subsequently exposed to the SQ‐origamis. High‐speed AFM revealed the dynamic adsorption/desorption behavior of the SQ‐origamis, which resulted in continuous changing of their arrangements in the framework. These dynamic SQ‐origamis were trapped in the cavities by increasing the Mg2+ concentration or by introducing sticky‐ended cohesions between extended staples, both from the SQ‐ and CR‐origamis, which enabled the directed docking of the SQ‐origamis. Our study offers a platform to create supramolecular structures or systems consisting of multiple DNA origami components.
Reactions of Fluoroalkenes with an Aluminium(I) Complex
Authors: Bakewell Clare , White Andrew J. P. , Crimmin Mark R. 
Published: April 2018

AbstractA series of industrially relevant fluoroalkenes react with a monomeric AlI complex. These reactions break strong sp2 and sp3 C−F bonds, and result in the formation of a diverse array of organoaluminium compounds. Mechanistic studies show that two mechanisms are likely in operation: 1) direct oxidative addition of the C−F bond to AlI occurs with retention of alkene stereochemistry, and 2) stepwise formation and decomposition of a metallocyclopropane intermediate occurs with inversion of alkene stereochemistry. As part of this mechanistic analysis, we have isolated the first aluminium metallocyclopropane complex from oxidative addition of an alkene to AlI. Remarkably this reaction is reversible and reductive elimination of the alkene occurs at higher temperature reforming AlI. Furthermore, in selected cases the organoaluminium products are susceptible toward β‐fluoride elimination to yield a double C−F activation pathway.
Kinetische Racematspaltung α‐hydroxysubstituierter Oximether durch enantioselektive Cu‐H‐katalysierte Si‐O‐Kupplung
Authors: Dong Xichang , Kita Yuji , Oestreich Martin 
Published: April 2018

AbstractEs wird über eine katalysatorkontrollierte, enantioselektive Alkoholsilylierung durch Cu‐H‐katalysierte dehydrierende Si‐O‐Kupplung von zu Oximethern α‐ständigen Hydroxygruppen und einfachen Hydrosilanen berichtet. Die in dieser kinetischen Racematspaltung erreichten Selektivitätsfaktoren sind gemeinhin hoch (s≈50), wodurch ein verlässlicher Zugang zu hoch enantiomerenangereicherten α‐hydroxysubstituierten Oximethern bereitgestellt wird. Deren Nutzen für die Synthese wird ebenfalls aufgezeigt.
Stabilisierung von Lewis‐azidem AuF3 mithilfe eines N‐heterocyclischen Carbens: Herstellung und Charakterisierung von [AuF3(SIMes)]
Authors: Ellwanger Mathias A. , Steinhauer Simon , Golz Paul , Braun Thomas , Riedel Sebastian 
Published: April 2018

AbstractZwei unterschiedliche Reaktionspfade zum Trifluoridoorganogold(III)‐Komplex [AuF3(SIMes)] werden beschrieben. Die Verbindung enthält das N‐heterocyclische Carben SIMes (1,3‐Bis(2,4,6‐trimethylphenyl)‐4,5‐dihydroimidazol‐2‐yliden) als Ligand an einer molekularen, Lewis‐aziden AuF3‐Einheit und wurde sowohl durch NMR‐Spektroskopie als auch mittels Röntgenstrukturanalyse charakterisiert. Außer der Verwendung eines [AuF4]−‐Salzes als Vorstufe ist auch der direkte Einsatz der stark oxidierenden Verbindung AuF3 möglich. Die Reaktion läuft sogar in organischen Lösungsmitteln in Gegenwart von freiem SIMes als Ligandenvorstufe ab. Hierbei können Zersetzungsreaktionen mit dem Lösungsmittel verhindert werden.
High‐Performance Sodium Metal Anodes Enabled by a Bifunctional Potassium Salt
Authors: Shi Qiuwei , Zhong Yiren , Wu Min , Wang Hongzhi , Wang Hailiang 
Published: April 2018

AbstractDeveloping Na metal anodes that can be deeply cycled with high efficiency for a long time is a prerequisite for rechargeable Na metal batteries to be practically useful despite their notable advantages in theoretical energy density and potential low cost. Their high chemical reactivity with the electrolyte and tendency for dendrite formation are two major issues limiting the reversibility of Na metal electrodes. In this work, we introduce for the first time potassium bis(trifluoromethylsulfonyl)imide (KTFSI) as a bifunctional electrolyte additive to stabilize Na metal electrodes, in which the TFSI− anions decompose into lithium nitride and oxynitrides to render a desirable solid electrolyte interphase layer while the K+ cations preferentially adsorb onto Na protrusions and provide electrostatic shielding to suppress dendritic deposition. Through the cooperation of the cations and anions, we have realized Na metal electrodes that can be deeply cycled at a capacity of 10 mAh cm−2 for hundreds of hours.
Intermolecular σ‐Bond Cross‐Exchange Reaction between Cyclopropenones and (Benzo)silacyclobutanes: Straightforward Access towards Sila(benzo)cycloheptenones
Authors: Zhao Wen‐Tao , Gao Fang , Zhao Dongbing 
Published: April 2018

AbstractDescribed herein is the first intermolecular σ‐bond exchange reaction between the C−C bond of cyclopropenones and C−Si bond of (benzo)silacyclobutanes and it proceeds smoothly by treatment with either 1 mol % of a palladium or 2 mol % of a nickel catalyst. This reaction constitutes an unprecedented route for the synthesis of various sila(benzo)suberones. And it is also the first example of a σ‐bond exchange reaction involving cyclopropenones.
Schwere Carbenhomologe: donorfreie Bismutenium‐ und Stibenium‐Ionen
Authors: Olaru Marian , Duvinage Daniel , Lork Enno , Mebs Stefan , Beckmann Jens 
Published: April 2018

AbstractKinetisch stabilisierte Kongenere von Carbenen, R2C, die sechs Valenzelektronen aufweisen (vier bindende und zwei nicht‐bindende Elektronen) waren bisher auf die Elemente der 14. Gruppe, R2E (E=Si, Ge, Sn, Pb; R=Alkyl oder Aryl), beschränkt, während die isoelektronischen Kationen der 15. Gruppe, zweiwertige Spezies des Typs [R2E]+(E=P, As, Sb, Bi; R=Alkyl oder Aryl), unbekannt waren. Hier wird über die ersten beiden Vertreter berichtet: das Bismutenium‐Ion [(2,6‐Mes2C6H3)2Bi][BArF4] (1, Mes=2,4,6‐Me3C6H2, ArF=3,5‐(CF3)2C6H3) und das Stibenium‐Ion [(2,6‐Mes2C6H3)2Sb][B(C6F5)4] (2), die durch den kombinierten Einsatz von sterisch anspruchvollen meta‐Terphenyl‐Substituenten und schwach koordinierenden Anionen erhalten wurden.
Oxygen Vacancies in ZnO Nanosheets Enhance CO2 Electrochemical Reduction to CO
Authors: Geng Zhigang , Kong Xiangdong , Chen Weiwei , Su Hongyang , Liu Yan , Cai Fan , Wang Guoxiong , Zeng Jie 
Published: April 2018

AbstractAs electron transfer to CO2 is generally considered to be the critical step during the activation of CO2, it is important to develop approaches to engineer the electronic properties of catalysts to improve their performance in CO2 electrochemical reduction. Herein, we developed an efficient strategy to facilitate CO2 activation by introducing oxygen vacancies into electrocatalysts with electronic‐rich surface. ZnO nanosheets rich in oxygen vacancies exhibited a current density of −16.1 mA cm−2 with a Faradaic efficiency of 83 % for CO production. Based on density functional theory (DFT) calculations, the introduction of oxygen vacancies increased the charge density of ZnO around the valence band maximum, resulting in the enhanced activation of CO2. Mechanistic studies further revealed that the enhancement of CO production by introducing oxygen vacancies into ZnO nanosheets originated from the increased binding strength of CO2 and the eased CO2 activation.
Shell‐Isolated Tip‐Enhanced Raman and Fluorescence Spectroscopy
Authors: Huang Ya‐Ping , Huang Sheng‐Chao , Wang Xiang‐Jie , Bodappa Nataraju , Li Chao‐Yu , Yin Hao , Su Hai‐Sheng , Meng Meng , Zhang Hua , Ren Bin , Yang Zhi‐Lin , Zenobi Renato , Tian Zhong‐Qun , Li Jian‐Feng 
Published: April 2018

AbstractTip‐enhanced Raman spectroscopy can provide molecular fingerprint information with ultrahigh spatial resolution, but the tip will be easily contaminated, thus leading to artifacts. It also remains a great challenge to establish tip‐enhanced fluorescence because of the quenching resulting from the proximity of the metal tip. Herein, we report shell‐isolated tip‐enhanced Raman and fluorescence spectroscopies by employing ultrathin shell‐isolated tips fabricated by atomic layer deposition. Such shell‐isolated tips not only show outstanding electromagnetic field enhancement in TERS but also exclude interference by contaminants, thus greatly promoting applications in solution. Tip‐enhanced fluorescence has also been achieved using these shell‐isolated tips, with enhancement factors of up to 1.7×103, consistent with theoretical simulations. Furthermore, tip‐enhanced Raman and fluorescence signals are acquired simultaneously, and their relative intensities can be manipulated by changing the shell thickness. This work opens a new avenue for ultrahigh resolution surface analysis using plasmon‐enhanced spectroscopies.