bluuebunny/crossref_metadata_2025 huggingface dataset:
Aspectos da arborização urbana ecológica
Authors: Bechara Fernando Campanhã , Topanotti Larissa Regina , Silva Lenir Maristela
Published: August 2017

A arborização urbana representa a possibilidade de o homem urbano resgatar frações da natureza que foram suprimidas para dentro de seu lar e de seus espaços comunitários. Este trabalho discorre sobre a “arborização urbana ecológica” que, além do plantio exclusivo de árvores nativas regionais e exclusão de espécies exóticas invasoras, se alicerça na biologia floral, fenologia, oferta permanente de alimentos para aves e polinizadores, conservação genética de espécies raras e ameaçadas de extinção e ecologia da paisagem. A arborização urbana ecológica reconhece a biodiversidade nativa como um valor cultural nas áreas urbanas, potencial em processos de conscientização e educação ambiental.
Análise descritiva da incorporação da variável ambiental na concessão de crédito no Brasil através do protocolo verde: um estudo de caso do BNDES
Authors: Maciel Harine Matos , Maciel Wlisses Matos
Published: August 2017

Este trabalho propõe-se analisar a incorporação da variável ambiental na concessão de crédito de Instituições Financeiras no Brasil, através do Protocolo Verde, dando ênfase no estudo de caso do Banco Nacional de Desenvolvimento Econômico e Social - BNDES, analisando a criação de suas linhas de crédito relativas ao meio ambiente. O BNDES é um banco estatal que foi criado para impulsionar o desenvolvimento econômico e social do Brasil. Começou a considerar formalmente a variável ambiental em suas análises de concessão de crédito a partir de 1976, pois para o BNDES a preservação, conservação e recuperação do meio ambiente são condições essenciais para a humanidade. O método de investigação científica principal utilizado foi o método dedutivo e o indutivo, partindo do objetivo da Contabilidade e dos Princípios Fundamentais de Contabilidade. Utilizou-se também a pesquisa e consulta de livros, revistas, artigos, documentários e sites da internet especializados no assunto, e relevantes sobre a incorporação da variável ambiental na concessão de crédito no Brasil. Dessa forma, conclui-se que se todos os bancos incluírem fortemente a variável ambiental como faz o BNDES, poderá haver o equilíbrio entre tecnologia e ambiente.
Alterações na microbiota e nos componentes químicos do solo provocados pela deposição de pilhas
Authors: Ciaca Alessandra Magalhaes
Published: August 2017

O solo é primordial para qualquer atividade humana, o estudo da sua composição microbiológica e química pode gerar várias indicações para o uso cuidadoso, sustentável e qualquer interferência de forma inadequada pode trazer consequências muitas vezes irreparáveis. Fatores bióticos e abióticos influenciam na respiração do solo e de maneira interativa apresentam efeitos sobre os componentes do mesmo. O objetivo da pesquisa foi avaliar as alterações na população de bactérias e fungos cultiváveis e nos componentes quimicos do solo provocados pela deposição de pilhas. O experimento foi conduzido em vasos preenchidos com terra onde foram depositadas pilhas alcalinas e secas a uma profundidade de 12 cm da superficie do vaso. Os vasos  ficaram na àrea externa da escola EMEF Prof Luiz Ribeiro Muniz,foram dispostos sobre manta plástica com a finalidade de evitar que os resíduos produzidos lixivissem no solo. Os tratamentos consistiram em deposição com pilhas alcalinas e pilhas secas nos solos dos vasos. As análises microbiológicas destes solos foram realizadas mensalmente por um período de 8 mês, enquanto que análise química do solo foi realizada no final do experimento. Verificou-se que a deposição de pilhas alcalinas e secas no solo provocaram alterações nas características químicas, principalmente de zinco e cobre. Maior concentração destes elementos foi verificada quando foram empregadas 4 pilhas. Foi constatado que a população de bactérias Gram-positivas, Gram-negativas e de fungos, foi reduzida em todos os tratamentos, havendo maior redução de fungos com as pilhas alcalinas. Sugere a necessidade de um trabalho educativo para cuidados com o solo e o descarte assertivo das pilhas.
Entraves e perspectivas da legislação sanitária para o desenvolvimento da cadeia da piscicultura em Dourados, Mato Grosso do Sul
Authors: Dias Elioterio Fachin , Carrijo Mauad Juliana Rosa , Silva Luciana Ferreira da , Garcia Rodrigo Garóffalo , Sgavioli Sarah
Published: August 2017

O Brasil apresenta potencial de crescimento para a cadeia produtiva do pescado, devido às condições naturais favoráveis, de clima, geografia, biodiversidade e água em abundância. A piscicultura ganhou visibilidade no município de Dourados/MS e na região, alcançando crescimento na produção de peixes. Este trabalho visa discutir sobre a sanidade e a qualidade do pescado, as legislações que regulam o serviço de inspeção sanitária dos produtos de origem animal e as políticas adotadas para produção e comercialização de pescado no município de Dourados e entorno. Realizou-se a análise de algumas normas e legislações sanitárias pertinentes ao Serviço de Inspeção Sanitária. Os dados e discussões permitiram constatar que políticas públicas, ações e normas sanitárias são necessárias e essenciais para a manutenção da qualidade e da sanidade do pescado, de modo a garantir a consolidação, a viabilidade técnica, econômica e socioambiental dos empreendimentos aquícolas no município e região, especialmente aos pequenos piscicultores.
Determinação de metais tóxicos em sedimento de canal de drenagem pluvial na zona urbana
Authors: Grimmler Marcelo Uarthe , Betemps Glauco Rasmussen , Ferreira Mariana Marcant , Sanches Filho Pedro José
Published: August 2017

Este estudo foi realizado em um canal de drenagem pluvial da zona urbana da cidade de Pelotas-RS, com o objetivo de determinar os níveis de metais tóxicos (Cr, Cu, Ni, Pb e Zn) no sedimento carreados pelo runoof. Foram coletadas amostra de sedimentos superficiais em cinco pontos ao longo do canal, a fração menor que 63µm sofreu de extração pseudo total nítrico-perclórica e os extratos foram analisados por espectrofotometria de absorção em chama . Os níveis de metais tóxicos encontrados variaram para o Cromo de 2,9 mg kg-¹±15,4% à 7,9 mg kg-¹±16,4%, Cobre de 4,7 mg kg-¹  ±11,0% à 20,5 mg kg-¹±6,2%. O Niquel foi detectado somente no ponto 2 no valor de 2,2 mg kg-¹±2,0%, Chumbo entre 5,4 mg kg-¹±2,9% à 22,6 mg kg-¹±3,5% e Zinco 49,0 mg kg-¹±4,1% à 100,2 mg kg-¹±6,8%. De maneira geral os analitos não ultrapassaram os limites estipulados pelo CONAMA 344/2004, não causando danos a biota e vida aquática.
Planejamento ótimo da água na agricultura irrigada: um estudo de caso em um perímetro paraibano
Authors: Pessoa Mariana Ferreira , Assis Lilian Figueirôa , Vieira Allan Sarmento
Published: August 2017

A agricultura irrigada é uma das atividades econômicas mais importantes desenvolvidas pelo homem e também a que mais consome água. Este trabalho consiste em um estudo no Perímetro Irrigado de São Gonçalo, localizado no distrito de São Gonçalo, na cidade de Sousa, Estado da Paraíba, tendo como principal objetivo, propor um planejamento ótimo, para o objeto de estudo, que considere um sistema de irrigação eficiente, culturas aptas à região, rentáveis e que consomem a menor quantidade de água possível. Para a realização desse planejamento, foi utilizado um modelo matemático, que utiliza técnicas de programação linear, que visa à obtenção de uma solução ótima para o problema, levando em consideração restrições como: a limitação da área total, a quantidade de água disponível, e a rotatividade das culturas. Em seguida foram definidos três cenários distintos, para uma melhor análise dos dados, ficando subdivididos por sistemas de irrigação (inundação, microaspersão e gotejamento) e por regimes hidroclimáticos (seco, médio e chuvoso). Os resultados mostraram que o sistema de irrigação por gotejamento é o mais eficiente, consequentemente obtém uma área irrigável maior. Verificou-se que as soluções propostas são propositivas, e que, se implementadas, vão proporcionar uma maior rentabilidade para os agricultores da região, aliadas as práticas sustentáveis.
Comparison between the municipal solid waste management of two municipalities from mountain region
Authors: Peresin Denise , Finkler Nícolas Reinaldo , Grando Mariana Riegel , Casagrande Verônica , Tonet Motta Elis Marina , Schneider Vania Elisabete
Published: August 2017

This paper aims to present a review of household waste management in two small municipalities located at Mountain Region (RS â€“ Brazil). As method, it was used data from waste amounts destined for regular and selective collection, physical characterization and gravimetric composition of the waste generated in three neighbourhoods of different social classes. It was observed that the largest municipality showed better efficiency and higher coverage of selective collection. The per capita index of waste generation was similar among municipalities, despite of differences in population size and in social and economic characteristics. The neighbourhoods with high and middle classes presented better segregation in both collections and municipalities. The presence of biodegradable materials in selective collection (average 14%) and recyclable materials in regular collection (average 21%) was observed. The obtained results indicated the necessity to continuously investing on expansion of selective collection and environmental education, in order to improve waste segregation, which contributes with the efficiency level of triage plants, as well as to increase the potential recovery of waste recyclable and the useful life of landfills.
Directional change during a Miocene R‐N geomagnetic polarity reversal recorded by mafic lava flows, Sheep Creek Range, north central Nevada, USA
Authors: Bogue S. W. , Glen J. M. G. , Jarboe N. A.
Published: August 2017

Recurring transitional field directions during three Miocene geomagnetic reversals provide evidence that lateral inhomogeneity of the lower mantle affects flow in the outer core. We compare new paleomagnetic results from a composite sequence of 15.2 Ma lava flows in north central Nevada (Sheep Creek Range; 40.7°N, 243.2°E), erupted during a polarity reversal, to published data from Steens Mountain (250 km to the northwest in Oregon) and the Newberry Mountains (650 km to the south in California) that document reversals occurring millions of years and many polarity switches earlier. Alternating field demagnetization, followed by thermal demagnetization in half the samples, clearly isolated the primary thermoremanent magnetization of Sheep Creek Range flows. We correlated results from our three sampled sections to produce a composite record that begins with a single virtual geomagnetic pole (VGP) at low latitude in the Atlantic, followed by two VGPs situated near latitude 30°N in NE Africa. After jumping to 83°N (one VGP), the pole moves to equatorial South America (one VGP), back to NE Africa (three VGPs), to high southern latitudes (two VGPs), back to equatorial South America (three VGPs), and finally to high northern latitudes (nine VGPs). The repeated visits of the transitional VGP to positions in South America and near NE Africa, as well as the similar behavior recorded at Steens Mountain and the Newberry Mountains, suggest that lower mantle or core‐mantle boundary features localize core flow structures, thereby imparting a discernible regional structure on the transitional geomagnetic field that persists for millions of years.
Heat flow bounds over the Cascadia margin derived from bottom simulating reflectors and implications for thermal models of subduction
Authors: Phrampus Benjamin J. , Harris Robert N. , Tréhu Anne M.
Published: August 2017

Understanding the thermal structure of the Cascadia subduction zone is important for understanding megathrust earthquake processes and seismogenic potential. Currently our understanding of the thermal structure of Cascadia is limited by a lack of high spatial resolution heat flow data and by poor understanding of thermal processes such as hydrothermal fluid circulation in the subducting basement, sediment thickening and dewatering, and frictional heat generation on the plate boundary. Here, using a data set of publically available seismic lines combined with new interpretations of bottom simulating reflector (BSR) distributions, we derive heat flow estimates across the Cascadia margin. Thermal models that account for hydrothermal circulation predict BSR‐derived heat flow bounds better than purely conductive models, but still over‐predict surface heat flows. We show that when the thermal effects of in‐situ sedimentation and of sediment thickening and dewatering due to accretion are included, models with hydrothermal circulation become consistent with our BSR‐derived heat flow bounds.
Cenozoic exhumation in the Qilian Shan, northeastern Tibetan Plateau: Evidence from detrital fission track thermochronology in the Jiuquan Basin
Authors: He Pengju , Song Chunhui , Wang Yadong , Chen Lihao , Chang Pengfei , Wang Qiangqiang , Ren Bo
Published: August 2017

The India‐Asia collision resulted in the Cenozoic framework of faults, ranges, and tectonic basins and the high topography of the northeastern Tibetan Plateau, but how and when these features formed remains poorly understood, leading to conflicting tectonic models. However, information on the tectonic evolution of these active orogenic belts is well preserved in synorogenic basin sediments. In this study, we carefully analyze the detrital apatite fission track ages of Cenozoic synorogenic sediments from the Jiuquan Basin to decipher the entire exhumation process of the adjacent Qilian Shan throughout the Cenozoic. Our data indicate that initially rapid Cenozoic exhumation occurred in the Qilian Shan during the late Paleocene‐early Eocene (~60–50 Ma), almost synchronous with the India‐Asia collision. The Qilian Shan subsequently experienced long‐lived exhumation that continued until at least the middle Miocene (~45–10 Ma). During this period of exhumation in the Qilian Shan, tectonic deformation occurred throughout the northeastern Tibetan Plateau. The early Cenozoic deformation in the northeastern Tibetan Plateau may have been caused by the transfer of tectonic stress from the distant India‐Asia collision boundary through the complex lithospheric environment of the Tibetan Plateau. The present tectonic configuration and topography of the Qilian Shan and the northeastern Tibetan Plateau likely became established since the middle Miocene and after the long‐lived deformation began in the early Cenozoic.
The high‐pressure phase of lawsonite: A single crystal study of a key mantle hydrous phase
Authors: O'Bannon Earl , Beavers Christine M. , Kunz Martin , Williams Quentin
Published: August 2017

Lawsonite CaAl2Si2O7(OH)2·H2O is an important water carrier in subducting oceanic crusts and the primary hydrous phase in basalt at depths greater than ~80 km. We have conducted high‐pressure synchrotron single‐crystal X‐ray diffraction experiments on natural lawsonite at room temperature up to ~10.0 GPa to study its high‐pressure polymorphism. We find that lawsonite remains orthorhombic with Cmcm symmetry up to ~9.3 GPa and shows nearly isotropic compression. Above ~9.3 GPa, lawsonite becomes monoclinic with P21/m symmetry. Across the phase transition, the Ca polyhedron becomes markedly distorted, and the average positions of the H2O molecules and hydroxyls change. The changes observed in the H‐atom positions under compression are different than the low‐temperature changes in this material. We resolve for the first time the H‐bonding configuration of the high‐pressure monoclinic phase of lawsonite. A bond valence approach is deployed to determine that the phase transition from orthorhombic to monoclinic is primarily driven by the Si2O7 groups, and in particular their bridging oxygen atoms (O1). The changes in the structure strongly indicate that entropy increases across the symmetry‐lowering transition and hence that the slope of the phase transition is negative. Monoclinic lawsonite is thus stable under the pressure and temperature conditions that exist in the Earth and is likely to be a major water carrier in colder, deep subducted slabs. Monoclinic lawsonite also likely has enhanced electrical conductivity along its c axis due to its dynamically disordered hydrogen atoms.
Field characterization of elastic properties across a fault zone reactivated by fluid injection
Authors: Jeanne Pierre , Guglielmi Yves , Rutqvist Jonny , Nussbaum Christophe , Birkholzer Jens
Published: August 2017

We studied the elastic properties of a fault zone intersecting the Opalinus Clay formation at 300 m depth in the Mont Terri Underground Research Laboratory (Switzerland). Four controlled water injection experiments were performed in borehole straddle intervals set at successive locations across the fault zone. A three‐component displacement sensor, which allowed capturing the borehole wall movements during injection, was used to estimate the elastic properties of representative locations across the fault zone, from the host rock to the damage zone to the fault core. Young's moduli were estimated by both an analytical approach and numerical finite difference modeling. Results show a decrease in Young's modulus from the host rock to the damage zone by a factor of 5 and from the damage zone to the fault core by a factor of 2. In the host rock, our results are in reasonable agreement with laboratory data showing a strong elastic anisotropy characterized by the direction of the plane of isotropy parallel to the laminar structure of the shale formation. In the fault zone, strong rotations of the direction of anisotropy can be observed. The plane of isotropy can be oriented either parallel to bedding (when few discontinuities are present), parallel to the direction of the main fracture family intersecting the zone, and possibly oriented parallel or perpendicular to the fractures critically oriented for shear reactivation (when repeated past rupture along this plane has created a zone).
Unraveling the onset of Cretaceous Oceanic Anoxic Event 2 in an extended sediment archive from the Tarfaya‐Laayoune Basin, Morocco
Authors: Kuhnt Wolfgang , Holbourn Ann E. , Beil Sebastian , Aquit Mohamed , Krawczyk Tim , Flögel Sascha , Chellai El Hassane , Jabour Haddou
Published: August 2017

We investigated the onset and development of Cretaceous Oceanic Anoxic Event 2 (OAE2) in a newly drilled core (SN°4) from the Tarfaya Basin (southern Morocco), where this interval is unusually expanded. High‐resolution (centimeter‐scale equivalent to centennial) analysis of bulk organic and carbonate stable isotopes and of carbonate and organic carbon content in combination with XRF scanner derived elemental distribution reveal that the ocean‐climate system behaved in a highly dynamic manner prior to and during the onset of OAE2. Correlation with the latest orbital solution indicates that the main carbon isotope shift occurred during an extended minimum in orbital eccentricity (~400 kyr cycle). Shorter‐term fluctuations in carbonate and organic carbon accumulation and in sea level related terrigenous discharge were predominantly driven by variations in orbital obliquity. Negative excursions in organic and carbonate δ13C preceded the global positive δ13C shift marking the onset of OAE2, suggesting injection of isotopically depleted carbon into the atmosphere. The main δ13C increase during the early phase of OAE2 in the late Cenomanian was punctuated by a transient plateau. Maximum organic carbon accumulation occurred during the later part of the main δ13C increase and was associated with climate cooling events, expressed as three consecutive maxima in bulk carbonate δ18O. The extinctions of the thermocline dwelling keeled planktonic foraminifers Rotalipora greenhornensis and Rotalipora cushmani occurred during the first and last of these cooling events and were likely associated with obliquity paced, ocean‐wide expansions, and intensifications of the oxygen minimum zone, affecting their habitat space on a global scale.
Improved electron collimation system design for Elekta linear accelerators
Authors: Pitcher Garrett M. , Hogstrom Kenneth R. , Carver Robert L.
Published: August 2017

Prototype 10 × 10 and 20 × 20‐cm2 electron collimators were designed for the Elekta Infinity accelerator (MLCi2 treatment head), with the goal of reducing the trimmer weight of excessively heavy current applicators while maintaining acceptable beam flatness (±3% major axes, ±4% diagonals) and IEC leakage dose. Prototype applicators were designed initially using tungsten trimmers of constant thickness (1% electron transmission) and cross‐sections with inner and outer edges positioned at 95% and 2% off‐axis ratios (OARs), respectively, cast by the upstream collimating component. Despite redefining applicator size at isocenter (not 5 cm upstream) and reducing the energy range from 4–22 to 6–20 MeV, the designed 10 × 10 and 20 × 20‐cm2 applicator trimmers weighed 6.87 and 10.49 kg, respectively, exceeding that of the current applicators (5.52 and 8.36 kg, respectively). Subsequently, five design modifications using analytical and/or Monte Carlo (MC) calculations were applied, reducing trimmer weight while maintaining acceptable in‐field flatness and mean leakage dose. Design Modification 1 beveled the outer trimmer edges, taking advantage of only low‐energy beams scattering primary electrons sufficiently to reach the outer trimmer edge. Design Modification 2 optimized the upper and middle trimmer distances from isocenter for minimal trimmer weights. Design Modification 3 moved inner trimmer edges inward, reducing trimmer weight. Design Modification 4 determined optimal X‐ray jaw positions for each energy. Design Modification 5 adjusted middle and lower trimmer shapes and reduced upper trimmer thickness by 50%. Design Modifications 1→5 reduced trimmer weights from 6.87→5.86→5.52→5.87→5.43→3.73 kg for the 10 × 10‐cm2 applicator and 10.49→9.04→8.62→7.73→7.35→5.09 kg for the 20 × 20‐cm2 applicator. MC simulations confirmed these final designs produced acceptable in‐field flatness and met IEC‐specified leakage dose at 7, 13, and 20 MeV. These results allowed collimation system design for 6 × 6–25 × 25‐cm2 applicators. Reducing trimmer weights by as much as 4 kg (25 × 25‐cm2 applicator) should result in easier applicator handling by the radiotherapy team.
Cholinergic activity and levodopa‐induced dyskinesia: a multitracer molecular imaging study
Authors: Brumberg Joachim , Küsters Sebastian , Al‐Momani Ehab , Marotta Giorgio , Cosgrove Kelly P. , van Dyck Christopher H. , Herrmann Ken , Homola György A. , Pezzoli Gianni , Buck Andreas K. , Volkmann Jens , Samnick Samuel , Isaias Ioannis U.
Published: August 2017

Objective

To investigate the association between levodopa‐induced dyskinesias and striatal cholinergic activity in patients with Parkinson's disease.

Methods

This study included 13 Parkinson's disease patients with peak‐of‐dose levodopa‐induced dyskinesias, 12 nondyskinetic patients, and 12 healthy controls. Participants underwent 5‐[123I]iodo‐3‐[2(S)‐2‐azetidinylmethoxy]pyridine single‐photon emission computed tomography, a marker of nicotinic acetylcholine receptors, [123I]N‐ω‐fluoropropyl‐2β‐carbomethoxy‐3β‐(4‐iodophenyl)nortropane single‐photon emission computed tomography, to measure dopamine reuptake transporter density and 2‐[18F]fluoro‐2‐deoxyglucose positron emission tomography to assess regional cerebral metabolic activity. Striatal binding potentials, uptake values at basal ganglia structures, and correlations with clinical variables were analyzed.

Results

Density of nicotinic acetylcholine receptors in the caudate nucleus of dyskinetic subjects was similar to that of healthy controls and significantly higher to that of nondyskinetic patients, in particular, contralaterally to the clinically most affected side.

Interpretation

Our findings support the hypothesis that the expression of dyskinesia may be related to cholinergic neuronal excitability in a dopaminergic‐depleted striatum. Cholinergic signaling would play a role in maintaining striatal dopaminergic responsiveness, possibly defining disease phenotype and progression.
Palladium‐Catalyzed Cross‐Coupling of Alkynyl Carboxylic Acids with Isocyanides: Solvent‐Controlled Selective Synthesis of 5‐Iminofuranones and 5‐Iminopyrrolones
Authors: Hu Weigao , Li Zun , Li Jiawei , Wu Wanqing , Liu Haiyang , Jiang Huanfeng
Published: August 2017

A novel palladium‐catalyzed cyclization of alkynyl carboxylic acids with isocyanides has been successfully developed herein. The corresponding 5‐iminofuranone or 5‐iminopyrrolone derivatives were constructed in moderate to good yields which were well controlled by the solvents. These reactions proceed under simple and mild reaction conditions with high efficiency, and feature a wide substrate scope, readily available starting materials and easy operation.

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Enantioselective Synthesis of Chiral Imidazolidine Derivatives by Asymmetric Silver/Xing‐Phos‐Catalyzed Homo‐1,3‐Dipolar [3+2] Cycloaddition of Azomethine Ylides
Authors: Yu Bo , Bai Xing‐Feng , Lv Ji‐Yuan , Yuan Yang , Cao Jian , Zheng Zhan‐Jiang , Xu Zheng , Cui Yu‐Ming , Yang Ke‐Fang , Xu Li‐Wen
Published: August 2017

Enantioselective synthesis of chiral heterocyclic derivatives is an important and challenging topic in the field of synthetic chemistry. In this work, the first stereocontrolled dimerization‐type homo‐1,3‐dipolar [3+2] cycloaddition reaction of glycine aldimino esters for creating new heterocycles bearing multiple stereogenic centers has been developed through chiral phosphine ligand‐involved silver catalysis. A variety of chiral imidazolidines could be obtained with high yields and good diastereoselectivities as well as excellent enantioselectivities by employing Xing‐Phos as chiral phosphorus ligand. In addition, the silver/Xing‐Phos‐catalyzed homo‐1,3‐dipolar [3+2] cycloaddition reaction is also a facile and novel protocol for catalytic polymerization of bifunctional glycine aldimino esters to give chiral poly(imidazolidine)s with a very narrow molecular weight distribution.

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Palladium‐Catalyzed Isocyanide Insertion with Allylic Esters: Synthesis of N‐(But‐2‐enoyl)‐N‐(tert‐butyl)benzamide Derivatives via Intramolecular Acyl Transfer Termination
Authors: Chen Si , Wei Wan‐Xu , Wang Jia , Xia Yu , Shen Yi , Wu Xin‐Xing , Jing Huanwang , Liang Yong‐Min
Published: August 2017

A novel and unprecedented intramolecular acyl transfer reaction via the palladium‐catalyzed insertion of isocyanide has been established. Isocyanides were inserted into C−O bond under mild conditions, using the readily available allyl ester as the starting materials. In addition, the intramolecular acyl transfer from the ester group oxygen atom to the isocyanide nitrogen atom afforded imide derivatives in moderate to excellent yields. Additionally, this transformation was validated as having operationally simple conditions and excellent functional group compatibility.

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Self‐Tuning n‐Type Bi2(Te,Se)3/SiC Thermoelectric Nanocomposites to Realize High Performances up to 300 °C
Authors: Pan Yu , Aydemir Umut , Sun Fu‐Hua , Wu Chao‐Feng , Chasapis Thomas C. , Snyder G. Jeffrey , Li Jing‐Feng
Published: August 2017

Bi2Te3 thermoelectric materials are utilized for refrigeration for decades, while their application of energy harvesting requires stable thermoelectric and mechanical performances at elevated temperatures. This work reveals that a steady zT of ≈0.85 at 200 to 300 °C can be achieved by doping small amounts of copper iodide (CuI) in Bi2Te2.2Se0.8–silicon carbide (SiC) composites, where SiC nanodispersion enhances the flexural strength. It is found that CuI plays two important roles with atomic Cu/I dopants and CuI precipitates. The Cu/I dopants show a self‐tuning behavior due to increasing solubility with increasing temperatures. The increased doping concentration increases electrical conductivity at high temperatures and effectively suppresses the intrinsic excitation. In addition, a large reduction of lattice thermal conductivity is achieved due to the “in situ” CuI nanoprecipitates acting as phonon‐scattering centers. Over 60% reduction of bipolar thermal conductivity is achieved, raising the maximum useful temperature of Bi2Te3 for substantially higher efficiency. For module applications, the reported materials are suitable for segmentation with a conventional ingot. This leads to high device ZT values of ≈0.9–1.0 and high efficiency up to 9.2% from 300 to 573 K, which can be of great significance for power generation from waste heat.
MicroRNA‐137 and microRNA‐195* inhibit vasculogenesis in brain arteriovenous malformations
Authors: Huang Jun , Song Jianping , Qu Meijie , Wang Yang , An Qingzhu , Song Yaying , Yan Wei , Wang Bingshun , Wang Xiaojin , Zhang Song , Chen Xi , Zhao Bing , Liu Peixi , Xu Tongyi , Zhang Zhijun , Greenberg David A. , Wang Yongting , Gao Pingjin , Zhu Wei , Yang Guo‐Yuan
Published: August 2017

Objective

Brain arteriovenous malformations (AVMs) are the most common cause of nontraumatic intracerebral hemorrhage in young adults. The genesis of brain AVM remains enigmatic. We investigated microRNA (miRNA) expression and its contribution to the pathogenesis of brain AVMs.

Methods

We used a large‐scale miRNA analysis of 16 samples including AVMs, hemangioblastoma, and controls to identify a distinct AVM miRNA signature. AVM smooth muscle cells (AVMSMCs) were isolated and identified by flow cytometry and immunohistochemistry, and candidate miRNAs were then tested in these cells. Migration, tube formation, and CCK‐8–induced proliferation assays were used to test the effect of the miRNAs on phenotypic properties of AVMSMCs. A quantitative proteomics approach was used to identify protein expression changes in AVMSMCs treated with miRNA mimics.

Results

A distinct AVM miRNA signature comprising a large portion of lowly expressed miRNAs was identified. Among these miRNAs, miR‐137 and miR‐195* levels were significantly decreased in AVMs and constituent AVMSMCs. Experimentally elevating the level of these microRNAs inhibited AVMSMC migration, tube formation, and survival in vitro and the formation of vascular rings in vivo. Proteomics showed the protein expression signature of AVMSMCs and identified downstream proteins regulated by miR‐137 and miR‐195* that were key signaling proteins involved in vessel development.

Interpretation

Our results indicate that miR‐137 and miR‐195* act as vasculogenic suppressors in AVMs by altering phenotypic properties of AVMSMCs, and that the absence of miR‐137 and miR‐195* expression leads to abnormal vasculogenesis. Ann Neurol 2017;82:371–384
Biopolymer foams from Novatein thermoplastic protein and poly(lactic acid)
Authors: Walallavita Anuradha Sammanie , Verbeek Casparus Johannes Reinhard , Lay Mark Christopher
Published: August 2017

A batch processing method is used to fabricate foams comprising of a blend of poly(lactic acid) (PLA) and Novatein, a protein‐based thermoplastic. Various compositions of Novatein/PLA are prepared with and without a compatibilizer, PLA grafted with itaconic anhydride (PLA‐g‐IA). Pure Novatein cannot form a cellular structure at a foaming temperature of 80 °C, however, in a blend with 50 wt % of PLA, microcells form with smaller cell sizes (3.36 µm) and higher cell density (8.44 × 1021 cells cm−3) compared to pure PLA and blends with higher amounts of PLA. The incorporation of 50 wt % of semicrystalline Novatein stiffens the amorphous PLA phase, which restrains cell coalescence and cell collapse in the blends. At a foaming temperature of 140 °C, NTP30–PLA70 shows a unique interconnected porous morphology which can be attributed to the CO2‐induced plasticization effect. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45561.
Poly(vinyl alcohol) and poly(vinyl amine) blend membranes for isopropanol dehydration
Authors: Chaudhari Shivshankar , Kwon YongSung , Moon MyungJun , Shon MinYoung , Nam SeungEun , Park YouIn
Published: August 2017

Blended membranes of hydrophilic polymers poly(vinyl alcohol) (PVA) and poly(vinyl amine) (PVAm) were prepared and crosslinked with glutaraldehyde. The prepared membranes were characterized using infrared (attenuated total reflection mode) spectroscopy, differential scanning calorimetry, X‐ray diffractometry, and scanning electron microscopy measurements. Pervaporation performances of the membranes were evaluated for the separation of water‐isopropanol (IPA) mixtures. As the PVAm content increased from PVAm0 to PVAm1.5, the flux through a 70 μm film increased from 0.023 to 0.10 kg/m2 h at an IPA/water feed ratio of 85/15 at 30 °C. The driving force for permeation of water increased due to the temperature but it has no effect on IPA permeation. Activation energies for the permeation of IPA and water were calculated to be 17.11 and 12.46 kJ/mol, respectively. Controlling the thickness of the blend membrane could improve the permeation flux with only a marginal reduction in the separation factor. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45572.
Synthesis, structure, and thermal properties of new polypropylene nanocomposites prepared by using MgCl2‐mica/TiCl4 based catalyst
Authors: Almeida Lidiane A. , Marques Maria de Fátima V. , Dahmouche Karim
Published: August 2017

Preparation of polypropylene/mica nanocomposites via in situ polymerization is investigated. The nanocomposites were successfully synthesized using a Ziegler‐Natta catalyst based on MgCl2/modified mica/TiCl4. Muscovite mica was organically modified with quaternary ammonium salt, and with triethylaluminum. The treatment with triethylaluminum increased the disorder in the stacking of clay layers, producing a more active catalyst for propylene polymerization, although the mica containing catalysts had lower activity than the standard one prepared without clay. The nanostructure of the composites was characterized by X‐ray diffraction. The results showed that part of the mica layers were exfoliated in the polymer matrix, although tactoids were still present. Small‐angle X‐ray scattering analysis was used to determine how mica and its concentration influence the size of the polymer nanocrystals. Differential scanning calorimetry was used to investigate both melting and crystallization temperatures, as well as the crystallinity of the nanocomposite samples. Thermogravimetric analysis showed that polypropylene/mica nanocomposites presented much higher thermal stability than the polypropylene without mica, which means that mica had a barrier effect against heat. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45587.
Improvement of thermal properties of pigmented acrylic resin using silica aerogel
Authors: Karami Sara , Motahari Siamak , Pishvaei Malihe , Eskandari Navid
Published: August 2017

In this study, two different types of acrylic resins were synthesized through emulsion polymerization. The first category of acrylic resins contained methyl methacrylate, 2‐ethylhexyl acrylate, and acrylic acid monomers. The second composition had an additional monomer named acrylamide (AAm). The kinetic behavior of polymerization reaction was investigated. The results showed that the presence of the AAm monomer increased the monomer conversion (>90% in the first 10 min) and the rate of polymerization. Furthermore, the latexes were characterized by Dynamic Light Scattering (DLS) Fourier Transform Infrared, and differential scanning calorimeter analysis. To study the effect of silica aerogel as a thermal barrier additive for acrylic resins, samples were mixed with silica aerogel using sodium dodecyl sulfate as a surfactant. In the next step, the above‐mentioned resins were used to make white acrylic‐based paints. The heat transfer measurements revealed that the thermal insulation properties were not affected by the composition of the resin. On the other hand, the use of AAm monomer increased the paint adhesion properties and helped the resin to receive more aerogel (up to 5 wt %) which in turn decreased the heat loss of the painted wall. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45640.
Recent progress in electrospinning TiO2 nanostructured photo‐anode of dye‐sensitized solar cells
Authors: Wan Tingting , Ramakrishna Seeram , Liu Yong
Published: August 2017

The key to improving the performance of dye‐sensitized solar cells is the photo‐anode that has much dye adsorption and short optoelectronic transmission path. Electrospun TiO2 films in photo‐anode have high specific surface area and meet the demand exactly. The article summarizes these efforts in TiO2 photo‐anode improvement, including various morphology, different one‐dimensional and two‐dimensional composite structure, and varied element doped TiO2 photo‐anode. Besides, the review makes comparison with these different TiO2 photo‐anodes in photoelectric properties. The conclusions provide a clear guidance in design of morphology, structure, and doping, which is helpful for researcher to improve the performance of the anode and increase the photoelectric conversion efficiency especially those prepared using electrospinning. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45649.
Dielectric behavior of sulfonated poly(styrene–isobutylene–styrene) triblock copolymer thin films
Authors: Rozo‐Medina Martha L. , Padovani Agnes M.
Published: August 2017

Sulfonated, block copolymers have traditionally been studied for applications in fuel cells and chemical protective clothing, among others. As such, most investigations have focused on the evaluation of transport properties and the selectivity and permeability of the polymer membranes. This work, however, focuses on the electrical characterization of sulfonated poly(styrene–isobutylene–styrene) (SIBS) triblock copolymer thin films. More specifically, the dielectric properties of SIBS are evaluated as a function of critical parameters such as frequency, sulfonation percent, and the polymer concentration. The results show that the dielectric constant increases with sulfonation percent and polymer concentration to values as high as 13,600. This work also provides insights into the correlation of SIBS electrical properties with its chemical structure and morphology. The structure–property relationship is derived through a combination of techniques including: elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and atomic force microscopy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45662.
New insight into the mechanism of enhanced crystallization of PLA in PLLA/PDLA mixture
Authors: Lv Tongxin , Zhou Chengbo , Li Jingqing , Huang Shaoyong , Wen Huiying , Meng Yanfeng , Jiang Shichun
Published: August 2017

Poly(lactic acid) (PLA) is a bio‐based and compostable polymer that has quickly developed into a competitive material, but the control of crystallinity is a bottleneck in extended utilization. The crystallization of PLA has been a rich topic because of the existence of two enantiomeric forms of poly(L‐lactic acid) (PLLA) and poly(d‐lactic acid) (PDLA) can form stereocomplex (SC) crystal with high melting point that can be used to control the crystallization behaviors. The SC crystal was regarded as an effective nucleating agent for promoting the crystallization rate and crystallinity of PLA. We investigated cold crystallization of PLLA/PDLA (1:1) mixture with in situ WAXS measurements and found that the homo‐crystal of PLA formed earlier than the SC‐crystal in the mixture within the measured temperature range, which is different from the melting crystallization. The final crystalline structures are in correspondence with the melting and cold crystallization temperature, and the transition of homo‐PLA (δ to α) is not altered by the crystallization procedure. The SC‐crystal can be detected in both cold and melting crystallization of the mixture at the temperatures lower than 150 °C, which is conflict with the reported results. A new crystallization mechanism of the mixture was proposed to understand the crystallization behaviors in PLLA/PDLA mixtures. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45663.
Normative data and psychometric properties of a farsi translation of the strange stories test
Authors: Shahrivar Zahra , Tehrani‐Doost Mehdi , Khorrami Banaraki Anahita , Mohammadzadeh Azar , Happe Francesca
Published: August 2017

Background and objective

The Strange Stories test is one of the most commonly used tests to evaluate advanced “theory of mind,” i.e. attribution of mental states. Normative data and psychometric properties of a new Farsi translation of this test were evaluated in a large community‐based sample of Iranian school‐aged children. Methods: Through randomized cluster sampling, 398 children aged 9–11 years studying at 20 elementary schools were recruited from 4 central regions of Tehran, Iran. The mean age of the students was 9.96 years (SD = 0.92), and 51% were girls (n = 202). The Child Behavior Checklist (CBCL) was completed by parents. The Strange Stories test was completed by all children and repeated for 20% of them after 2–4 weeks to assess the test‐retest reliability. Findings: Students in upper grades had higher scores (P < .01); age predicted 2% of variance on the mental state score. Girls had significantly higher mentalizing scores than boys (P = .003). The split‐half internal reliability coefficient was good (0.73). The test‐retest reliability was fair to good. Item‐scale score correlations were all significant (P < .01). Conclusion: This new translation of the Strange Stories test is a reliable and valid instrument to evaluate higher level theory of mind abilities in community samples of Farsi speaking children. Autism Res 2017, 10: 1960–1967. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

“Mentalizing” or “theory of mind,” the ability to recognize others' mental states, is a key aspect of social understanding. Mentalizing problems are characteristic of some clinical conditions such as autism. The Strange Stories is a test evaluating mentalizing in every day social situations. It was translated into Farsi language and administered to a group of Iranian school‐aged children. The instrument was useful in assessing children's mind reading. Older children and girls were better in mentalizing ability.
Early autism symptoms in infants with tuberous sclerosis complex
Authors: McDonald Nicole M. , Varcin Kandice J. , Bhatt Rujuta , Wu Joyce Y. , Sahin Mustafa , Nelson Charles A. , Jeste Shafali S.
Published: August 2017

Tuberous sclerosis complex (TSC) is a rare, autosomal dominant genetic syndrome that confers significantly increased risk for autism spectrum disorder (ASD), with 50–60% of infants with TSC meeting criteria for ASD by 3 years of age. In a previous study of the current longitudinal cohort, we found that infants with TSC who develop ASD (TSC/ASD) evidence decreased cognitive abilities that diverge from infants with TSC and no ASD (TSC/no ASD). We extended this work by asking whether TSC/ASD infants (n = 13) differed from TSC/no ASD infants (n = 10) and infants with low developmental risk and no ASD (LR; n = 21) in their social communication functioning during the first year of life. We measured early ASD symptoms with the Autism Observation Scale for Infants (AOSI) at 9 and 12 months of age. At both ages, infants in the TSC/ASD group had significantly higher AOSI total scores than infants in the TSC/no ASD and LR groups, which were not fully explained by differences in cognitive abilities. Several items on the AOSI at both ages were predictive of ASD outcome, particularly those representing core social communication deficits (e.g., social referencing). Our findings signal the need for further study of this population within the first year and provide strong justification for early identification and early intervention targeting social communication skills in infants with TSC. Autism Res 2017, 10: 1981–1990. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

We examined early signs of autism spectrum disorder (ASD) in infants with tuberous sclerosis complex (TSC), approximately 50% of whom will meet criteria for ASD by age 3. Infants with TSC and ASD showed deficits in social communication behaviors by 9 months of age that were clearly distinguishable from behaviors in infants with TSC who do not develop ASD and low risk infants. Results support the importance of early ASD screening and intervention for infants with TSC.
Recombinant Lactococcus lactis for efficient conversion of cellodextrins into L‐lactic acid
Authors: Gandini Chiara , Tarraran Loredana , Kalemasi Denis , Pessione Enrica , Mazzoli Roberto
Published: August 2017

Lactic acid bacteria (LAB) are among the most interesting organisms for industrial processes with a long history of application as food starters and biocontrol agents, and an underexploited potential for biorefineries converting biomass into high‐value compounds. Lactic acid (LA), their main fermentation product, is among the most requested chemicals owing to its broad range of applications. Notably, LA polymers, that is, polylactides, have high potential as biodegradable substitutes of fossil‐derived plastics. However, LA production by LAB fermentation is currently too expensive for polylactide to be cost‐competitive with traditional plastics. LAB have complex nutritional requirements and cannot ferment inexpensive substrates such as cellulose. Metabolic engineering could help reduce such nutritional requirements and enable LAB to directly ferment low‐cost polysaccharides. Here, we engineered a Lactococcus lactis strain which constitutively secretes a β‐glucosidase and an endoglucanase. The recombinant strain can grow on cellooligosaccharides up to at least cellooctaose and efficiently metabolizes them to L‐LA in single‐step fermentation. This is the first report of a LAB able to directly metabolize cellooligosaccharides longer that cellohexaose and a significant step toward cost‐sustainable consolidated bioprocessing of cellulose into optically pure LA.
Biocidal Potential and Chemical Composition of Industrial Essential Oils from Hyssopus officinalis, Lavandula × intermedia var. Super, and Santolina chamaecyparissus
Authors: Ortiz de Elguea‐Culebras Gonzalo , Sánchez‐Vioque Raúl , Berruga María Isabel , Herraiz‐Peñalver David , González‐Coloma Azucena , Andrés María Fé , Santana‐Méridas Omar
Published: August 2017

This work presents the biocidal (insecticidal, ixodicidal, nematicidal, and phytotoxic) effects and chemical compositions of three essential oils obtained from the industrial steam distillation (IEOs) of hyssop (Hyssopus officinalis L.), lavandin (Lavandula × intermedia or L. × hybrida var. Super), and cotton lavender (Santolina chamaecyparissus L.). Their chemical composition analyzed by gas chromatography coupled to mass spectrometry showed 1,8‐cineole (53%) and β‐pinene (16%) as the major components of H. officinalis, linalyl acetate (38%) and linalool (29%) of L. × intermedia; and 1,8‐cineole (10%) and 8‐methylene‐3‐oxatricyclo[5.2.0.02,4]nonane (8%) in S. chamaecyparissus. The biocidal tests showed that L. × intermedia IEO was the most active against the insect Spodoptera littoralis and toxic to the tick Hyalomma lusitanicum, IEO of H. officinalis was strongly active against S. littoralis, and finally, S. chamaecyparissus IEO was a strong antifeedant against the aphid Rhopalosiphum padi, toxic to H. lusitanicum and with moderate effects against Leptinotarsa decemlineata, S. littoralis, and Lolium perenne.