bluuebunny/crossref_metadata_2025 huggingface dataset:
Impactos decorrentes do uso do solo em dolinas da Bacia Sedimentar da Paraíba, zona oeste do município de João Pessoa (PB), Brasil/Resulting impacts of land use in dolines of the Paraiba (...)
Authors: Vital Saulo Roberto de Oliveira , Travassos Luiz Eduardo Panisset
Published: July 2015

O objetivo principal deste trabalho é destacar de que forma as dolinas presentes na Bacia Sedimentar da Paraíba são utilizadas na zona oeste do município de João Pessoa (PB) e alertar para o risco iminente de poluição e contaminação da água subterrânea. Para tanto, foi realizada a interpretação do uso e ocupação do solo com base em critérios de fotointerpretação convencional e sensoriamento remoto a partir da imagem do satélite Rapideye, de modo que os alvos foram delimitados (vetorizados) a partir de um Sistema de Informações Geográficas (SIG). As classes foram discernidas com base na classificação proposta em Melo et al. (2001) e IBGE (2006). A partir do estabelecimento da relação entre o uso do solo e a localização das depressões na zona urbana de João Pessoa (PB), percebeu-se que a maioria dessas feições se encontra localizada em área urbana, o que tem acarretado em diversos impactos, dentre eles poluição das águas, eutrofização e assoreamento. Tais problemas têm influenciado diretamente na vida das populações aí residentes, potencializando os riscos de enchentes, podendo ocasionar poluição das águas superficiais e subsuperficiais. Estudos geofísicos devem ser realizados visando mensurar a ocorrência de vazios ligados ao processo de carstificação e suas relações com o avanço urbano.Palavras-chave: dolinas, uso e cobertura das terras, poluição e contaminação, João Pessoa (PB).AbstractThe main objective of this paper is to show how the dolines present in the Paraiba Sedimentary Basin are used in the metropolitan area of João Pessoa (PB) and mention the imminent risk of pollution and contamination of groundwater. Thus, the authors performed the interpretation of land based on conventional photo interpretation and remote sensing criteria from the RapidEye satellite image, so that the targets were defined (vectored) from a Geographic Information System (GIS). The classes were discerned based on the classification proposed by Melo et al. (2001) and IBGE (2006). From the establishment of the relationship between land use and the location of the depressions in the urban area of João Pessoa (PB), it was noted that most of these features are located on the urban area, which has led several impacts, including water pollution, eutrophication and sedimentation. Such problems have direct influence in the lives of people living there, increasing the risk of flooding and pollution of surface and subsurface waters. Geophysical studies should be conducted to measure the occurrence of empty voids linked to karstification process and its relationship with the urban growth.Keywords: sinkholes, use and coverage of land, pollution and contamination, João Pessoa (PB).
Atividades acadêmicas e poluição sonora: análise do ruído ambiental no entorno da PUC Minas em Betim / Academic activities and noise pollution: an analysis of the environmental noise at the vicinities (...)
Authors: Pereira Jéssica Martielly Nunes , Laureano Fernando Verassani
Published: July 2015

O presente trabalho discute os resultados do monitoramento de ruído ambiental para os anos de 2010, 2011, 2012 e 2013 realizado pela PUC Minas em Betim no interior e no entorno do campus. O objetivo é testar a hipótese de que o ruído emitido no desempenho das atividades acadêmicas no interior do campus está em conformidade com a legislação e que, portanto, o cenário de poluição sonora do entorno não está diretamente associada às atividades da instituição. Das 244 aferições realizadas nos pontos externos 144 (59%) superaram os valores de referência. Dessas 21% apresentaram níveis sonoros superiores a 65 dB(A), ou seja, acima do limite recomendado pela Organização Mundial de Saúde (OMS) como limiar ao dano à saúde. Em contra partida, todas as 162 aferições realizadas nos pontos internos apresentaram valores abaixo do valor recomendado. Durante o período letivo a quantidade de medições em desconformidade apresentou um incremento em relação ao período de férias. Os dados também mostram que os níveis de ruído apresentaram maior amplitude durante o período letivo, aumentando assim a probabilidade de ocorrências de valores acima dos 65 dB(A). O incremento no quadro de poluição sonora no entorno da universidade está associado ao inerente aumento no fluxo de veículos e pessoas durante o período letivo.Palavra-chave: Monitoramento; Poluição sonora; Universidade; Betim.AbstractNoise monitoring had been performed inside and around PUC Minas Betim in order to test the hypothesys that surrounding noise pollution is not associated with academic activities. 144 (59%) of 244 external measurements exceeded legal benchmark values, in which 21% also exceeded World Health Organization 65 dB(A) threshold for health damage. On the other hand, 162 internal measurements showed results below the recommended limit. Although this pollution scenario is recurrent, the amount of non-conform measurements and noise amplitude rise during class times when compared to vacation periods. This rising is not however due the activities performed inside the campus but the associated increment on people and vehicles traffic around the university during class time.Keyword: Monitoring; Noise pollution; University; Betim.
Influência de alguns elementos climáticos na produção de serrapilheira em um reflorestamento de pinus na FLONA (Floresta Nacional) de Irati- PR / Influence of some climatic elements in the production (...)
Authors: Antoneli Valdemir , Francisquini Viviane
Published: July 2015

O presente estudo tem por objetivo avaliar a produção de serrapilheira em um Reflorestamento de pinus na Floresta Nacional de Irati/Paraná (FLONA), e correlacioná-los com alguns elementos climáticos. No monitoramento da produção de serrapilheira, foram utilizados coletores de 1x1 (1m2), totalizando 12 coletores. As coletas foram realizadas mensalmente e, o material retirado dos coletores foi seco, pesado e em seguida separado em três frações: folhas, galhos e miscelânea. A deposição de serrapilheira no reflorestamento de pinus foi de 13.098 (kg/ha). Observou-se ao correlacionar os dados mensais, que a chuva foi a variável de maior influência na deposição de serrapilheira (r= 0,570), já os outros fatores, apresentaram baixa correlação. No entanto, verificou-se que há uma alta correlação entre as variáveis climáticas e a deposição de serrapilheira quando os dados são analisados sazonalmente. Esta alta correlação pode estar atrelada ao efeito tardio, desses fatores, ou seja, a deposição de serrapilheira não é imediata as variações climáticas.  Palavras-chave: serrapilheira; fatores climáticos; sazonalidade; FLONA   AbstractThis study aims to evaluate litter production in a reforestation of pinus in the National Forest (FLONA) of Irati / Paraná and correlate them with some climatic elements. In the  monitoring of the production of litter, 1x1 (1m2), totaling 12 collectors. Samples were collected monthly, and the material taken from the collectors was dried and weighed and then separated into three fractions: leaves branches and miscellaneous. The deposition of litter in the reforestation of pinus was of 13.098 (kg/ha).Was observed to correlate the monthly data that rain was the most influential variable in the deposition of litter, as other factors, had low correlation. However, it was found that there is a high correlation between climatic variables and deposition of litter when the data are analyzed seasonally. This high correlation may be linked to the late effect, these factors; in this case the deposition of litter is not immediate climatic variations.  Keywords: litter; climatic elements; seasonally; FLONA.
Proposta Metodológica para Identificação de vilas e povoados mineiros localizados mais próximos das sedes municipais de outros municípios vizinhos / Methodological proposal for identification of (...)
Authors: De Oliveira Gabriel Luís Nogueira , Baeta Aliane Maria Motta , Rodrigues Brenner Henrique Maia , Nunes Marcos Antônio , Matos Ralfo Edmundo Da Silva
Published: July 2015

Esta pesquisa é o resultado de estudos realizados para o projeto “Implantação do Laboratório de Atendimento às Demandas de Limites Municipais e Distritais de Minas Gerais”, executado pelo Instituto de Geoinformação e Tecnologia (IGTEC), da Secretaria de Estado de Ciência, Tecnologia e Ensino Superior do Governo de Minas Gerais. O projeto demandou o desenvolvimento de uma metodologia através da qual pudesse identificar os casos de ocorrência das vilas (sedes distritais) e dos povoados dos municípios mineiros que se encontram a distâncias inferiores às das sedes de municípios vizinhos em relação às suas respectivas sedes municipais. A metodologia se pautou pelas distâncias em linha reta, obtidas a partir dos centroides dos setores censitários dos municípios mineiros. O levantamento desses casos é importante para a compreensão do transbordamento de serviços intermunicipais e subsidiar a organização territorial do estado de Minas Gerais.Palavras-chave: Sedes Municipais; Vilas e Povoados; Setores censitários; Minas Gerais. AbstractThis research is the result of studies for the project “Implantação do Laboratório de Atendimento às Demandas de Limites Municipais e Distritais de Minas Gerais", executed by Instituto de Geoinformação e Tecnologia (IGTEC), part of the State Secretariat of Science, Tecnology and Superior Education of Minas Gerais government. The project required the development of a methodology to identify cases of occurrence of villages (districtal headquarters) and hamlets of Minas Gerais’ municipalities which are located closer to the other municipality headquarter instead of the own headquarter. The methodology was based by the distances in a straight line, obtained from the census sectors’ centroids. The survey of these cases is important to understand the overflow of intercity services and to support the territorial organization of the state of Minas Gerais.Keywords: Municipal headquarters; Villages and hamlets; Census sectors; Minas Gerais.
A Cidade pensada teoricamente / The City considered theoretically
Authors: Ramos Edivaldo Fernandes
Published: July 2015

ResumoToda teoria tem a sua contribuição que pode responder ou não às necessidades interpretativas de um dado momento histórico, mas que sempre provoca a discussão e a reflexão sobre o tema, o que a torna importante. É pensando nesta questão que o objetivo do presente texto é discutir o conceito de cidade a partir da literatura sobre o tema, analisando os principais aspectos a serem considerados na sua interpretação.  Buscar-se-á aqui realizar uma discussão teórica sobre a cidade, tentando relacionar as contribuições das principais correntes de pensamento sobre a temática e os pontos de divergência e convergência entre eles.Palavras chave: Cidade, Teoria, Urbano.AbstractEvery theory has its contribution that can respond or not interpretative needs of a given historical moment, but that always provokes discussion and reflection on the theme, which makes it important. Is thinking about this question that the goal of this paper is to discuss the concept of city from the literature on the subject, analyzing the main aspects to be considered in its interpretation.Get yourself here carry a theoretical discussion about the city, trying to relate the contributions of the main currents of thought on the subject and the points of divergence and convergence between them. Keywords: City, Theory, Urban.
A popularização do Centro / The popularization of the center
Authors: Jesus Cláudio Roberto de
Published: July 2015

O objetivo deste artigo é problematizar e recolocar em debate o processo de transformação das áreas centrais das metrópoles brasileiras na passagem do século XX para o XXI, com especial atenção para as transformações ocorridas em Belo Horizonte, Minas Gerais. Pretende-se questionar a ideia de degradação das áreas centrais, apontando o caráter ideológico de tal termo e sua insuficiência como componente de explicação de processos múltiplos e complexos.Palavras-chave: popularização; Belo Horizonte; degradação. AbstractThe purpose of this article is to discuss and debate replacing the transformation process of the central areas of Brazilian cities in the passage of the twentieth century to century, with special attention to the changes occurring in Belo Horizonte, Minas Gerais. It is intended to question the idea of degradation of the core areas, pointing out the ideological character of such term and its failure as a component of explanation of multiple and complex processes.Keywords: popularization; Belo Horizonte; degradation.
O impacto do uso de ferramenta de visualização de dados abertos como recurso de ensino e aprendizagem / The impact of use open data visualization tools how teaching and learning resource
Authors: Lobo Alex Alex Sander Miranda , Maia Luiz Claudio Gomes , Parreiras Fernando Silva
Published: July 2015

Este artigo apresenta uma pesquisa de dissertação, na qual se buscou desenvolver uma ferramenta de visualização de Dados Abertos (Open Data) para uso no processo de ensino e aprendizagem em uma turma do terceiro ano do Ensino Médio na disciplina de Geografia. Teve como objetivo principal verificar como essa ferramenta influenciaria nesse processo. Para atingir o objetivo do trabalho, foi realizada uma pesquisa preponderantemente qualitativa com natureza descritiva, com referencial teórico baseado na aprendizagem significativa e no uso das tecnologias da informação e comunicação no processo de ensino e aprendizagem. Foi realizada uma entrevista inicial junto ao professor da disciplina e a aplicação de questionários ao professor e aos alunos do terceiro ano, após o uso da aplicação de visualização de dados abertos e, por fim, foi proposto um teste avaliativo entre turmas que usaram o aplicativo e turmas que não o usaram. Na análise dos resultados, concluiu-se que a ferramenta trouxe vários aspectos positivos no processo de ensino e aprendizagem, como uma atenção maior por parte dos alunos em relação ao conteúdo, uma motivação a mais no processo de ensino e aprendizagem, tendo apresentado aspectos relacionados à aprendizagem significativa e mostrado que os alunos que fizeram o uso da aplicação tiveram um melhor desempenho em relação aos que não fizeram o uso da tecnologia no conteúdo proposto na disciplina.Palavras-Chave: Educação. Dados Abertos. Ensino e AprendizagemAbstractThis article presents a research dissertation, which aimed to develop a visualization tool of Open Data (Open Data) for use in the process of teaching and learning in a class of third year of high school in geography discipline. Aimed to assess how these influence tool in this process. To achieve the goal of the work, mainly qualitative research was conducted with descriptive, and the theoretical framework based on meaningful learning and the use of information and communication technologies in teaching and learning. An initial interview was conducted with the subject teacher and the application of questionnaires to teachers and students of the third year after the use of open data visualization application and, finally, an evaluation test between groups who used the application was proposed and classes than used. In analyzing the results, it was concluded that the tool has brought many positive aspects in the process of teaching and learning, such as greater attention from students regarding the content, one more motivation in the process of teaching and learning, presenting aspects the significant learning and shown that students who have made the use of the application performed better than those who did not make the use of technology in the proposed content of the discipline.Keywords: Education. Open Data. Teaching and Learning.
Réalisme ontologique et subjectivité politique chez
Durkheim : quelques traits hégéliens du fondateur de
la sociologie
Authors: Filion Jean-François
Published: July 2015

L’objectif du présent article consiste à développer l’hypothèse suivant laquelle la conception durkheimienne de la société inclut une dimension suprasensible de nature éthico-politique, qui existe indépendamment de la connaissance sociologique et qui oriente la pratique humaine. Ce réalisme ontologique se rapproche nettement de l’idéalisme objectif de Hegel. Ainsi, Durkheim critique l’atomisme libéral pour les mêmes raisons que Hegel, c’est-à-dire à partir d’une conception similaire de la société et de la liberté. Tous les deux développent un concept républicaniste de la liberté en mettant l’accent sur la nécessité que les individus parviennent à adhérer à la structure des médiations de la société – l’État et les institutions sociales – moyennant le développement d’une disposition d’esprit politique que permet la participation au monde des idéaux fécondés par une foi en un sens suprasocial.
Protocadherin-dependent dendritic self-avoidance regulates neural connectivity and circuit function
Authors: Kostadinov Dimitar , Sanes Joshua R
Published: July 2015

Dendritic and axonal arbors of many neuronal types exhibit self-avoidance, in which branches repel each other. In some cases, these neurites interact with those of neighboring neurons, a phenomenon called self/non-self discrimination. The functional roles of these processes remain unknown. In this study, we used retinal starburst amacrine cells (SACs), critical components of a direction-selective circuit, to address this issue. In SACs, both processes are mediated by the gamma-protocadherins (Pcdhgs), a family of 22 recognition molecules. We manipulated Pcdhg expression in SACs and recorded from them and their targets, direction-selective ganglion cells (DSGCs). SACs form autapses when self-avoidance is disrupted and fail to form connections with other SACs when self/non-self discrimination is perturbed. Pcdhgs are also required to prune connections between closely spaced SACs. These alterations degrade the direction selectivity of DSGCs. Thus, self-avoidance, self/non-self discrimination, and synapse elimination are essential for proper function of a circuit that computes directional motion.
TEC prediction performance of IRI‐2012 model during a very low and a high solar activity phase over equatorial regions, Uganda
Authors: Tariku Yekoye Asmare
Published: July 2015

This paper examines the capacity of the latest version of the International Reference Ionosphere (IRI‐2012) model in predicting the vertical total electron content (VTEC) variation over Uganda during a very low solar activity phase (2009) and a high solar activity (2012) phase. This has been carried out by comparing the ground‐based Global Positioning System (GPS) VTEC inferred from dual‐frequency GPS receivers installed at Entebbe (geographic latitude 0.038°N and longitude 32.44°E; geomagnetic latitude −9.53°N and longitude 104.06°E) and Mbarara (geographic latitude −0.60°N and longitude 30.74°E; geomagnetic latitude −10.02°N and longitude 102.36°E). In this work, the diurnal, monthly, and seasonal variations in the measured VTEC have been analyzed and compared with the VTEC derived from IRI‐2012 model. It has been shown that the lowest diurnal peak GPS‐VTEC values are observed in the June solstice months during both the low and the high solar activity phases. Similarly, the highest diurnal peak IRI‐2012 VTEC values are observed in equinoctial months during both phases. The variability of the VTEC in both the experimental and model is minimal nearly at 03:00 UT (06:00 LT) and maximal mostly between 10:00 and 13:00 UT (13:00–16:00 LT) during both phases. The diurnal highest peak modeled VTEC value observed during the high solar activity phase is almost twice larger than the diurnal highest peak modeled VTEC value depicted during the low solar activity phase. Moreover, the highest monthly mean hourly measured VTEC value observed in October during the high solar activity phase is larger by more than twice the corresponding highest monthly mean hourly measured VTEC value observed in November during the low solar activity phase. Similarly, the lowest monthly measured VTEC value observed in July during the high solar activity phase is larger by more than twice the corresponding lowest measured monthly VTEC value observed in the same month during the low solar activity phase. It has also been shown that the highest measured seasonal mean hourly VTEC values are observed in the December solstice and the March equinox, respectively, during the low and the high solar activity phases, while the corresponding lowest measured VTEC values are observed in the June solstice during both phases. The model prediction generally follows the monthly and seasonal variations of measured VTEC, with the highest and the lowest monthly values being observed in equinoctial and solstice months, respectively, during both phases. The overall results show that the modeled diurnal, monthly, and seasonal VTEC values are generally larger than those corresponding measured VTEC values observed during both the low and the high solar activity phases, with the largest deviations being observed during the low solar activity phase. Moreover, the model does not respond to the effects resulting from the storm. Hence, unlike the measured VTEC values, the modeled VTEC values are unaffected by the storm.
Dynamics of glide avalanches and snow gliding
Authors: Ancey Christophe , Bain Vincent
Published: July 2015

In recent years, due to warmer snow cover, there has been a significant increase in the number of cases of damage caused by gliding snowpacks and glide avalanches. On most occasions, these have been full‐depth, wet‐snow avalanches, and this led some people to express their surprise: how could low‐speed masses of wet snow exert sufficiently high levels of pressure to severely damage engineered structures designed to carry heavy loads? This paper reviews the current state of knowledge about the formation of glide avalanches and the forces exerted on simple structures by a gliding mass of snow. One particular difficulty in reviewing the existing literature on gliding snow and on force calculations is that much of the theoretical and phenomenological analyses were presented in technical reports that date back to the earliest developments of avalanche science in the 1930s. Returning to these primary sources and attempting to put them into a contemporary perspective are vital. A detailed, modern analysis of them shows that the order of magnitude of the forces exerted by gliding snow can indeed be estimated correctly. The precise physical mechanisms remain elusive, however. We comment on the existing approaches in light of the most recent findings about related topics, including the physics of granular and plastic flows, and from field surveys of snow and avalanches (as well as glaciers and debris flows). Methods of calculating the forces exerted by glide avalanches are compared quantitatively on the basis of two case studies. This paper shows that if snow depth and density are known, then certain approaches can indeed predict the forces exerted on simple obstacles in the event of glide avalanches or gliding snow cover.
Impacts of evaporation on subsurface flow and salt accumulation in a tidally influenced beach
Authors: Geng Xiaolong , Boufadel Michel C.
Published: July 2015

We coupled a mass‐transfer formulation of evaporation to the density‐dependent variably saturated finite element model MARUN to predict the salinity under realistic conditions in a beach in the Gulf of Mexico. The results showed that evaporation almost doubled the pore water salt concentration in the intertidal zone in comparison to the case with no evaporation. The results also showed that for the relatively wet atmospheric conditions, the maximum evaporation did not occur from the supratidal zone, rather from the intertidal zone, and it was due to the difference in moisture between pore water and atmosphere. The highest salinity occurred during the spring tide period, and extended into the neap tide period. When the atmospheric condition was assumed to be constant and conducive to large evaporation (high temperature and low air humidity), the maximum salinity region shifted to the supratidal zone and persisted there due to low mixing. The maximum salinity value in the intertidal zone for this case was not larger than that of the variable atmospheric condition case. However, the maximum was more landward than the (more realistic) variable atmospheric condition case, which suggests that accurate characterization of pore water salinity in tidally influenced beaches requires accurate knowledge of atmospheric conditions in addition to beach and hydraulic properties. The constant atmospheric condition simulations suggest that antecedent extreme conditions greatly affect the salinity in the supratidal zone but they are dampened in the intertidal zone.
Enhancement of plume dilution in two‐dimensional and three‐dimensional porous media by flow focusing in high‐permeability inclusions
Authors: Ye Yu , Chiogna Gabriele , Cirpka Olaf A. , Grathwohl Peter , Rolle Massimo
Published: July 2015

In porous media, lateral mass exchange exerts a significant influence on the dilution of solute plumes in quasi steady state. This process is one of the main mechanisms controlling transport of continuously emitted conservative tracers in groundwater and is fundamental for the understanding of many degradation processes. We investigate the effects of high‐permeability inclusions on transverse mixing in three‐dimensional versus two‐dimensional systems by experimental, theoretical, and numerical analyses. Our results show that mixing enhancement strongly depends on the system dimensionality and on the parameterization used to model transverse dispersion. In particular, no enhancement of transverse mixing would occur in three‐dimensional media if the local transverse dispersion coefficient was uniform and flow focusing in both transverse directions was identical, which is fundamentally different from the two‐dimensional case. However, the velocity and grain size dependence of the transverse dispersion coefficient and the correlation between hydraulic conductivity and grain size lead to prevailing mixing enhancement within the inclusions, regardless of dimensionality. We perform steady state bench‐scale experiments with multiple tracers in three‐dimensional and quasi two‐dimensional flow‐through systems at two different velocities (1 and 5 m/d). We quantify transverse mixing by the flux‐related dilution index and compare the experimental results with model simulations. The experiments confirm that, although dilution is larger in three‐dimensional systems, the enhancement of transverse mixing due to flow focusing is less effective than in two‐dimensional systems. The spatial arrangement of the high‐permeability inclusions significantly affects the degree of mixing enhancement. We also observe more pronounced compound‐specific effects in the dilution of solute plumes in three‐dimensional porous media than in two‐dimensional ones.
The future of water resources systems analysis: Toward a scientific framework for sustainable water management
Authors: Brown Casey M. , Lund Jay R. , Cai Ximing , Reed Patrick M. , Zagona Edith A. , Ostfeld Avi , Hall Jim , Characklis Gregory W. , Yu Winston , Brekke Levi
Published: July 2015

This paper presents a short history of water resources systems analysis from its beginnings in the Harvard Water Program, through its continuing evolution toward a general field of water resources systems science. Current systems analysis practice is widespread and addresses the most challenging water issues of our times, including water scarcity and drought, climate change, providing water for food and energy production, decision making amid competing objectives, and bringing economic incentives to bear on water use. The emergence of public recognition and concern for the state of water resources provides an opportune moment for the field to reorient to meet the complex, interdependent, interdisciplinary, and global nature of today's water challenges. At present, water resources systems analysis is limited by low scientific and academic visibility relative to its influence in practice and bridled by localized findings that are difficult to generalize. The evident success of water resource systems analysis in practice (which is set out in this paper) needs in future to be strengthened by substantiating the field as the science of water resources that seeks to predict the water resources variables and outcomes that are important to governments, industries, and the public the world over. Doing so promotes the scientific credibility of the field, provides understanding of the state of water resources and furnishes the basis for predicting the impacts of our water choices.
Gas pressure gradients in unsaturated porous media and the assumption of infinite gas mobility
Authors: Hou Lili , Sleep Brent E. , Kibbey Tohren C. G.
Published: July 2015

The assumption that gas is infinitely mobile, moving without viscous pressure drops, is common in studies of unsaturated flow in porous media. The objectives of this work were to use experimental measurements to examine that assumption in systems experiencing rapid drainage and to explore the extent to which observed pressure drops could be described by conventional multiphase flow simulation tracking viscous flow in both phases. Because many published studies have used vented columns in an effort to equilibrate pore gas pressures with inlet gas, an additional objective of the work was to use experimental measurements to explore the ability of column vents to equilibrate pore gas with inlet gas during dynamic drainage. Results of the work suggest that gas pressure gradients can be significant, and that the assumption of infinite gas mobility is likely to be unsatisfactory in many systems where moderately rapid saturation change occurs. While vents have the potential to influence flow by providing additional gas inlets, experimental results of this work show almost no impact on pore gas pressures from a vent similar in size to those in other published studies. An equation developed as a part of the work suggests that the spatial slope of gas pressure with distance away from the front during dynamic drainage is proportional to the ratio of outflow Darcy velocity to saturated hydraulic conductivity for vertical columns. As such, systems with more rapid saturation change also have a greater potential to exhibit experimental artifacts related to gas pressure gradients.
Physical Function, Hyperuricemia, and Gout in Older Adults
Authors: Burke Bridget Teevan , Köttgen Anna , Law Andrew , Gwen Windham Beverly , Segev Dorry , Baer Alan N. , Coresh Josef , McAdams‐DeMarco Mara A.
Published: July 2015

Objective

Gout prevalence is high in older adults and those affected are at risk of physical disability, yet it is unclear whether they have worse physical function.

Methods

We studied gout, hyperuricemia, and physical function in 5,819 older adults (age ≥65 years) attending the 2011–2013 Atherosclerosis Risk in Communities Study visit, a prospective US population‐based cohort. Differences in lower extremity function (Short Physical Performance Battery [SPPB] and 4‐meter walking speed) and upper extremity function (grip strength) by gout status and by hyperuricemia prevalence were estimated in adjusted ordinal logistic regression (SPPB) and linear regression (walking speed and grip strength) models. Lower scores or times signify worse function. The prevalence of poor physical performance (first quartile) by gout and hyperuricemia was estimated using adjusted modified Poisson regression.

Results

Ten percent of participants reported a history of gout and 21% had hyperuricemia. There was no difference in grip strength by history of gout (P = 0.77). Participants with gout performed worse on the SPPB test; they had 0.77 times (95% confidence interval [95% CI] 0.65, 0.90, P = 0.001) the prevalence odds of a 1‐unit increase in SPPB score and were 1.18 times (95% CI 1.07, 1.32, P = 0.002) more likely to have poor SPPB performance. Participants with a history of gout had slower walking speed (mean difference −0.03; 95% CI −0.05, −0.01, P < 0.001) and were 1.19 times (95% CI 1.06, 1.34, P = 0.003) more likely to have poor walking speed. Similarly, SPPB score and walking speed, but not grip strength, were worse in participants with hyperuricemia.

Conclusion

Older adults with gout and hyperuricemia are more likely to have worse lower extremity, but not upper extremity, function.
Biofabricated Nanoparticle Coating for Liver‐Cell Targeting
Authors: Zhang Cheng , Qu Xue , Li Jinyang , Hong Hua , Li Jianbo , Ren Jie , Payne Gregory F. , Liu Changsheng
Published: July 2015

Biology routinely uses noncovalent interactions to perform complex functions that range from the molecular recognition of ligand–receptor binding to the reversible self‐assembly/disassembly of hierarchical nanostructures (e.g., virus particles). Potentially, biological materials that offer such recognition and reversible self‐assembly functionality can be applied to nanomedicine. Here, polysaccharides with the multifunctional polysaccharide‐binding protein Concanavalin A (Con A) are coupled to create a functional nanoparticle coating. This coating is self‐assembled in a layer‐by‐layer format by sequentially contacting a nanoparticle with Con A and the polysaccharide glycogen. In the final assembly step, a galactomannan targeting ligand is self‐assembled into the coating. Evidence indicates that the mannose residues of the galactomannan backbone are responsible for assembly into the coating by Con A binding, while the galactose side chain residues are responsible for targeting to the liver‐specific asialoglycoprotein receptor (ASGP‐R). Binding to ASGP‐R induces endocytic uptake, while the low endosomal pH triggers disassembly of the coating and release of the nanoparticle‐entrapped drug. In vitro cell studies indicate that the coating confers liver‐cell‐specific function for both nanoparticle uptake and drug delivery. These studies extend the use of Con A to sugar‐mediated and organ‐specific targeting, and further illustrate the potential of biologically based fabrication for generating functional materials.
Nanofibrous Spongy Microspheres Enhance Odontogenic Differentiation of Human Dental Pulp Stem Cells
Authors: Kuang Rong , Zhang Zhanpeng , Jin Xiaobing , Hu Jiang , Gupte Melanie J. , Ni Longxing , Ma Peter X.
Published: July 2015

Dentin regeneration is challenging due to its complicated anatomical structure and the shortage of odontoblasts. In this study, a novel injectable cell carrier, nanofibrous spongy microspheres (NF‐SMS), is developed for dentin regeneration. Biodegradable and biocompatible poly(l‐lactic acid)‐block‐poly(l‐lysine) are synthesized and fabricated into NF‐SMS using self‐assembly and thermally induced phase separation techniques. It is hypothesized that NF‐SMS with interconnected pores and nanofibers can enhance the proliferation and odontogenic differentiation of human dental pulp stem cells (hDPSCs), compared to nanofibrous microspheres (NF‐MS) without pore structure and conventional solid microspheres (S‐MS) with neither nanofibers nor pore structure. During the first 9 d in culture, hDPSCs proliferate significantly faster on NF‐SMS than on NF‐MS or S‐MS (p< 0.05). Following in vitro odontogenic induction, all the examined odontogenic genes (alkaline phosphatase content, osteocalcin, bone sialoprotein, collagen 1, dentin sialophosphoprotein (DSPP)), calcium content, and DSPP protein content are found significantly higher in the NF‐SMS group than in the control groups. Furthermore, 6 weeks after subcutaneous injection of hDPSCs and microspheres into nude mice, histological analysis shows that NF‐SMS support superior dentin‐like tissue formation compared to NF‐MS or S‐MS. Taken together, NF‐SMS have great potential as an injectable cell carrier for dentin regeneration.
Grafting Low Contents of Branched Polyethylenimine onto Carbon Fibers to Effectively Improve Their Interfacial Shear Strength with an Epoxy Matrix
Authors: Tang Xiu‐Zhi , Yu Bin , Hansen Reinack Varghese , Chen Xuelong , Hu Xiao , Yang Jinglei
Published: July 2015

The mechanical properties of carbon fiber (CF) reinforced composites are greatly dependent on the interfacial strength between the CFs and matrix. To improve the interfacial adhesion of carbon fiber/epoxy composites, branched polyethylenimine (PEI) is grafted onto the CFs treated in a mixed acid at optimized process time. The chemical compositions and bonds of functionalized CFs are characterized by thermal gravimetric analysis, Fourier‐transform infrared, and X‐ray photoelectron spectroscopy. The surface structures and morphologies of various CFs are analyzed by Raman spectroscopy and scanning electron microscopy, respectively. Microbond test is adopted to evaluate the interfacial shear strength (IFSS) between the CFs and epoxy matrix. The results show that the CFs modified by low molecular weight PEI are better than those modified by high molecular weight PEI. The IFSS of PEI modified CFs can reach a maximum of 107.2 ± 14.3 MPa at a low functionalization degree compared with 78.1 ± 11.6 MPa of unmodified CFs. The branched structure and high density of active amine groups on the PEI chains are responsible for the improved interfacial strength.
Classical density functional theory for methane adsorption in metal‐organic framework materials
Authors: Fu Jia , Tian Yun , Wu Jianzhong
Published: July 2015

Natural gas is considered as a promising alternative to petroleum as the next generation of primary transportation fuel owing to relatively smaller carbon footprint and lower SOx/NOx emissions and to fast developments of shale gas in recent years. Since the volumetric energy density of methane amounts to only about 1% of that of gasoline at ambient conditions, natural gas storage represents one of the key challenges for prevalent deployment of natural gas vehicles. In this work, we present a molecular thermodynamic model potentially useful for high‐throughput screening of nanoporous materials for natural gas storage. We investigate methane adsorption in a large library of metal‐organic frameworks (MOFs) using four versions of classical density functional theory (DFT) and calibrate the theoretical predictions with extensive simulation data for total gas uptake and delivery capacity. In combination with an extended excess entropy scaling method, the classical DFT is also used to predict the self‐diffusion coefficients of the confined gas in several top‐ranked MOFs. The molecular thermodynamic model has been used to identify promising MOF materials and possible variations of operation parameters to meet the Advanced Research Projects Agency‐Energy (ARPA‐E) target set by the U.S. Department of Energy for natural gas storage. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3012–3021, 2015
Familial TAB2 microdeletion and congenital heart defects including unusual valve dysplasia and tetralogy of fallot
Authors: Weiss Karin , Applegate Carolyn , Wang Tao , Batista Denise A. S.
Published: July 2015

Haploinsufficiency of TAB2 was recently implicated as a cause for a variety of congenital heart defects. Reported cases have genomic deletions of 2–10 Mbs including TAB2 at 6q24–25 are almost always de novo and show variable cardiac and extra cardiac phenotype. We report on an inherited, 281 kb deletion in a three generation family. This is the smallest reported deletion involving TAB2 that segregates with congenital heart defects. Three affected individuals in this family present with myxomatous cardiac valves in addition to structural heart defects commonly associated with TAB2 deletions. Findings from this family support a key role of TAB2 haploinsufficiency in congenital heart defects and expand the phenotypic spectrum of TAB2‐microdeletion syndrome. © 2015 Wiley Periodicals, Inc.
Dexamethasone affects mouse olfactory mucosa gene expression and attenuates genes related to neurite outgrowth
Authors: Tian Jun , Pinto Jayant M. , Xin Yi , Zhang Henghui , Li Li , Sun Zhifu , Wei Yongxiang
Published: July 2015

Background

Olfaction is one of the important senses for humans. Systemic glucocorticoids are the most commonly used medications for olfactory loss because of their strong anti‐inflammatory effects. However, their effect on olfactory function is still controversial and the precise mechanism is not clear. To gain a global view of the effect of systematic glucocorticoid treatment on gene expression in the olfactory mucosa (OM), we profiled these changes in a murine model of olfaction in order to identify underlying molecular mechanisms.

Methods

C57BL/6 mice were injected daily for 2 weeks (WK2) with dexamethasone (DEX, intraperitoneally, 1 mg/kg body weight) vs 1 day of DEX (D1) vs controls, which received saline (Ctrl) (n = 9/group). Total RNA from the OM was used to analyze global gene expression. Genes showing changes in expression were compared using the Database for Annotation, Visualization and Integrated Discovery (DAVID, v6.7) and the General Olfactory Sensitivity Database (GOSdb; http://genome.weizmann.ac.il/GOSdb).

Results

Between the WK2 and Ctrl groups, 3351 genes were differentially expressed, of which 236 genes were related to olfactory function. Genes involved in axon guidance, cell projection, and inflammation were enriched and overlapped significantly with those in the GOSdb.

Conclusion

Systemic glucocorticoids exert effects on transcription of a notable number of genes in the OM and appear to orchestrate changes related to axon guidance, cell projection, and inflammation. Further examination may allow targeted therapies that lack the side effects of this category of medication.
S‐Doping of an Fe/N/C ORR Catalyst for Polymer Electrolyte Membrane Fuel Cells with High Power Density
Authors: Wang Yu‐Cheng , Lai Yu‐Jiao , Song Lin , Zhou Zhi‐You , Liu Jian‐Guo , Wang Qiang , Yang Xiao‐Dong , Chen Chi , Shi Wei , Zheng Yan‐Ping , Rauf Muhammad , Sun Shi‐Gang
Published: July 2015

Fe/N/C is a promising non‐Pt electrocatalyst for the oxygen reduction reaction (ORR), but its catalytic activity is considerably inferior to that of Pt in acidic medium, the environment of polymer electrolyte membrane fuel cells (PEMFCs). An improved Fe/N/C catalyst (denoted as Fe/N/C‐SCN) derived from Fe(SCN)3, poly‐m‐phenylenediamine, and carbon black is presented. The advantage of using Fe(SCN)3 as iron source is that the obtained catalyst has a high level of S doping and high surface area, and thus exhibits excellent ORR activity (23 A g−1 at 0.80 V) in 0.1 M H2SO4 solution. When the Fe/N/C‐SCN was applied in a PEMFC as cathode catalyst, the maximal power density could exceed 1 W cm−2.
Aryne‐Induced Novel Tandem 1,2‐Addition/(3+2) Cycloaddition to Generate Imidazolidines and Pyrrolidines
Authors: Swain Sharada P. , Shih Yi‐Chun , Tsay Shwu‐Chen , Jacob Joby , Lin Chun‐Cheng , Hwang Kuo Chu , Horng Jia‐Cherng , Hwu Jih Ru
Published: July 2015

A new “single‐flask” method was developed for the synthesis of imidazolidines and pyrrolidines with high stereoselectivity. First, a Schiff base was arylated with an aryne. Second, an intramolecular proton transfer took place from the methylene position to the anionic aryne ring. Third, the resultant ylide reacted with a second equivalent of the same Schiff base in situ or an electron‐deficient alkene through a (3+2) cycloaddition. These sequential tandem 1,2‐addition/(3+2) cycloaddition reactions led to the desired heterocycles in 63–88 % yields.
Curved Oligophenylenes as Donors in Shape‐Persistent Donor–Acceptor Macrocycles with Solvatofluorochromic Properties
Authors: Kuwabara Takuya , Orii Jun , Segawa Yasutomo , Itami Kenichiro
Published: July 2015

Many optoelectronic organic materials are based on donor–acceptor (D–A) systems with heteroatom‐containing electron donors. Herein, we introduce a new molecular design for all‐carbon curved oligoparaphenylenes as donors, which results in the generation of unique shape‐persistent D–A macrocycles. Two types of acceptor‐inserted cycloparaphenylenes were synthesized. These macrocycles display positive solvatofluorochromic properties owing to their D–A characteristics, which were confirmed by theoretical and electrochemical studies.
PC‐Activated Bimetallic Rhodium Xantphos Complexes: Formation and Catalytic Dehydrocoupling of Amine–Boranes
Authors: Johnson Heather C. , Weller Andrew S.
Published: July 2015

{Rh(xantphos)}‐based phosphido dimers form by PC activation of xantphos (4,5‐bis(diphenylphosphino)‐9,9‐dimethylxanthene) in the presence of amine–boranes. These dimers are active dehydrocoupling catalysts, forming polymeric [H2BNMeH]n from H3B⋅NMeH2 and dimeric [H2BNMe2]2 from H3B⋅NMe2H at low catalyst loadings (0.1 mol %). Mechanistic investigations support a dimeric active species, suggesting that bimetallic catalysis may be possible in amine–borane dehydropolymerization.
18F‐Labeling of Aryl‐SCF3, ‐OCF3 and ‐OCHF2 with [18F]Fluoride
Authors: Khotavivattana Tanatorn , Verhoog Stefan , Tredwell Matthew , Pfeifer Lukas , Calderwood Samuel , Wheelhouse Katherine , Lee Collier Thomas , Gouverneur Véronique
Published: July 2015

We report that halogenophilic silver(I) triflate permits halogen exchange (halex) nucleophilic 18F‐fluorination of aryl‐OCHFCl, ‐OCF2Br and ‐SCF2Br precursors under mild conditions. This AgI‐mediated process allows for the first time access to a range of 18F‐labeled aryl‐OCHF2, ‐OCF3 and ‐SCF3 derivatives, inclusive of [18F]riluzole. The 18F‐labeling of these medicinally important motifs expands the radiochemical space available for PET applications.
Aqueous Self‐Assembly of Purely Hydrophilic Block Copolymers into Giant Vesicles
Authors: Brosnan Sarah M. , Schlaad Helmut , Antonietti Markus
Published: July 2015

Self‐assembly of macromolecules is fundamental to life itself, and historically, these systems have been primitively mimicked by the development of amphiphilic systems, driven by the hydrophobic effect. Herein, we demonstrate that self‐assembly of purely hydrophilic systems can be readily achieved with similar ease and success. We have synthesized double hydrophilic block copolymers from polysaccharides and poly(ethylene oxide) or poly(sarcosine) to yield high molar mass diblock copolymers through oxime chemistry. These hydrophilic materials can easily assemble into nanosized (<500 nm) and microsized (>5 μm) polymeric vesicles depending on concentration and diblock composition. Because of the solely hydrophilic nature of these materials, we expect them to be extraordinarily water permeable systems that would be well suited for use as cellular mimics.
Covalent Protein Labeling by Enzymatic Phosphocholination
Authors: Heller Katharina , Ochtrop Philipp , Albers Michael F. , Zauner Florian B. , Itzen Aymelt , Hedberg Christian
Published: July 2015

We present a new protein labeling method based on the covalent enzymatic phosphocholination of a specific octapeptide amino acid sequence in intact proteins. The bacterial enzyme AnkX from Legionella pneumophila has been established to transfer functional phosphocholine moieties from synthetically produced CDP‐choline derivatives to N‐termini, C‐termini, and internal loop regions in proteins of interest. Furthermore, the covalent modification can be hydrolytically removed by the action of the Legionella enzyme Lem3. Only a short peptide sequence (eight amino acids) is required for efficient protein labeling and a small linker group (PEG‐phosphocholine) is introduced to attach the conjugated cargo.