bluuebunny/crossref_metadata_2025 huggingface dataset:
Ilhéus, a terra da Gabriela cravo e canela: de espaço do cacau a espaço do turismo
Authors: Moreira Gilsélia Lemos
Published: February 2018

O trabalho em questão analisa as transformações socioespaciais da cidade de Ilhéus, a partir dos anos de 1990, período em que ocorreu uma grave crise no setor produtivo regional baseado na lavoura cacaueira e, coincidentemente, a valorização da atividade turística no Brasil, fator desencadeador de uma visível ressignificação do turismo em toda a região cacaueira. Como objetivo principal, pretende compreender os vários processos que levaram Ilhéus, cidade que surge subordinada ao campo, a passar da condição de espaço do cacau a espaço do turismo. Para alcançar esse objetivo, foram feitas entrevistas e pesquisas de natureza documental. Inicia-se o texto com uma digressão histórica sobre o processo de produção e reprodução socioespacial de Ilhéus, desde o século XVIII, quando chegaram a Ilhéus as primeiras mudas de cacau. Essa pesquisa revelou que diante da crise e das fracassadas tentativas de revitalizar a lavoura cacaueira, o turismo, atividade até então relegada a um segundo plano, passou a fazer parte da pauta de interesse da iniciativa privada e do poder público. Isso por força da necessidade de reerguer a economia regional.

Abstract

ILHÉUS: THE HOMETOWN OF GABRIELA, CLOVE AND CINNAMON: FROM CACAO SPACE TO TOURISTIC SITE

This work analyses the sociospatial changes in the city called Ilhéus starting in the 1990’s when there was a serious crisis in the regional productive sector based on cacao crops and, coincidentaly, the valorization of the touristic activity in Brazil, key reason of a visible reframing of tourism all over the cacao region. As a main objective, this work intends to understand the various processes that guided Ilhéus, city that was developed linked to the fields, to change from cacao space to touristic site. To reach our goal, interviews and documentary researches were made. The text begins with a historic degression about the process of production and sociospatial reproduction of Ilhéus, dating the 18th century, when the first samplings of cacao got to Ilhéus. This research revealed that in face of the crisis and the unsuccessful attempts to revitalize cacao plantations, the tourism, activity so far left as a second option, started its journey as an item of interest of private businesses and public power. That due to the necessity of rebuilding regional economy.
30 anos de Encontros Nacionais de Geografia Agrária (ENGAs): um “raio X” da produção do conhecimento sobre a temática da relação cidade-campo
Authors: Travagim Viturino Neves Karina Fernanda
Published: February 2018

Neste artigo apresentamos alguns dos resultados da pesquisa que foi defendida no curso de Mestrado em Geografia da Universidade Federal da Bahia. Por meio de pesquisa bibliográfica analisamos os anais dos Encontros Nacionais de Geografia Agrária (ENGAs) com o objetivo de investigar questões relativas à produção do conhecimento sobre a temática da relação cidade-campo no Brasil no âmbito da ciência geográfica. Investigamos os anais de todos os dezenove eventos realizados até a defesa da pesquisa, compreendendo o período de 1978-2009, e selecionamos 281 trabalhos que discutiam a temática da relação cidade-campo para compor nossa base de dados. Especificamente para esse artigo, reunimos os resultados referentes ao histórico e à importância dos ENGAs; à caracterização da fonte de dados da pesquisa bibliográfica e ao panorama da produção de conhecimento sobre a temática da relação cidade-campo no Brasil, a partir dos anais desse encontro científico.

Resumé

30 ANS DE RENCONTRES NATIONALES DE GEOGRAPHIE AGRAIRE (ENGAs): UN «RAYON X» DE LA PRODUCTION DE CONNAISSANCES SUR LE THÈME DE RELATION VILLE-CAMPAGNE

Dans cet article, nous présentons quelques résultats de la recherche qui a été défendu au cours de Master en Géographie de la Université Fédérale de Bahia. Par une recherche bibliographique nous avons analysé les annales des Rencontres Nationales de Géographie Agraire (ENGAs) afin d’enquêter des questions liées à la production de connaissances sur le thème de la relation ville-campagne au Brésil dans le cadre de la science géographique. Nous avons étudié les annales de tous les événements dix-neuf qui ont été effectués jusqu’à la finalization de la recherche, couvrant la période de 1978 à 2009 et nous avons selectionné 281 ouvrages qui traitait du thème de la relation ville-campagne pour composer notre base de données. Spécifiquement pour cet article, nous avons recueilli les résultats relatifs à l’histoire et l’impor- tance de Engas; l’identification des caractéristiques de la source des données de la recherche bibliographique et la exposition du panorama de la production de connaissances sur le thème de la relation entre ville et campagne au Brésil, dans les annales de cette rencontre scientifique.

Relations ville-campagne; Épistémologie de la Géographie; Géographie Agraire brésilienne; Rencontres Nationales de Géographie Agraire
Eventos extremos e risco de inundação: uma análise do comportamento evolutivo dos Distúrbios Ondulatórios de Leste em junho de 2010 sobre a bacia do rio Una - Pernambuco
Authors: Alves Keyla Manuela Alencar da Silva , Cavalcanti Lucas Costa de Souza , Nóbrega Ranyére Silva
Published: February 2018

Os Distúrbios Ondulatórios de Leste (DOL’s) são perturbações dos ventos alísios que, no Nordeste do Brasil, geralmente se associam a eventos extremos de precipitação. Este trabalho analisa o comportamento evolutivo de um DOL que atingiu o Estado de Pernambuco em junho de 2010, provocando inundações e grandes prejuízos humanos e econômicos. O recorte escolhido para análise foi a bacia hidrográfica do rio Una, que teve 11 municípios afetados. A análise do evento baseou-se na interpretação de imagens GOES-12 realçadas e TRMM. Constatou-se que a análise de imagens GOES-12 isoladas não produz uma resposta eficaz, no entanto, quando associada a mais informações, chega a uma resposta concisa e de extrema importância para os estudos relacionados a eventos climáticos. Para avaliação da vulnerabilidade à inundação das diversas sedes municipais da bacia do Una, utilizou-se um estimador de densidade Kernel baseado nos valores de magnitude da rede de drenagem. Os resultados indicaram que mesmo áreas naturalmente menos vulneráveis podem ser seriamente afetadas em função do montante precipitado.

Abstract

EXTREME EVENTS AND FLOOD RISK: AN ANALYSIS OF THE EVOLUTIONARY PROCEEDING OF EASTERLY WAVES DISTURBS IN JUNE 2010 ON THE WATERSHED OF UNA RIVER - PERNAMBUCO

The easterly waves (DOL’s) are disorders of the trade winds, which, in northeastern Brazil, usually are associated with extreme precipitation events. This paper examines the evolutionary pattern of a DOL that hit the state of Pernambuco in June 2010, causing flooding and severe economic losses humans. The clipping chosen for analysis was the Una river basin, which had 11 affected municipalities. The analysis of the event based on the interpretation of images GOES-12 and TRMM. It was found that the analysis of GOES-12 images isolated not produce an effective, however, when combined with more information, come to a concise answer and extremely important for studies related to climate events. To evaluate the vulnerability to flooding of several municipal seats Una river basin, used a kernel density estimator based on the magnitude values of the drainage network. The results indicated that even naturally less vulnerable areas can be seriously affected by the amount precipitated.
Conteúdos e transformações recentes na rede de cidades no sudoeste da Amazônia brasileira (Rondônia e Acre)
Authors: Pereira Mirlei Fachini Vicente
Published: February 2018

No sudoeste amazônico (estados de Rondônia e Acre) um recente processo de modernização acaba por atualizar conteúdos territoriais que se expressam tanto em um novo conjunto de objetos (formas materiais), quanto na vida que os anima (ações). A implicação mais direta desse processo se manifesta, de certo modo, numa redefinição de funções na rede de cidades, tornando-a mais complexa na medida em que incorpora uma nova divisão territorial do trabalho. Novos conteúdos são inseridos, mas problemas antigos persistem, reforçando as desigualdades territoriais.

Abstract

CONTEN TS AND RECEN T CHANGES IN THE NE TWORK CI TIES IN SOUTHWES T OF BRA ZILIAN AMAZON (ROND ÔNIA AND ACRE)

In southwestern Amazonia (Rondonia and Acre) a recent process of modernization produces a territorial content update, which is expressed in a new set of objects (material forms) and the life that them animates (actions). The more direct implication of this process is manifested, in some measure, in a redefinition of the functions of cities in the network cities, which becomes more complex, because it incorporates one new territorial divisions of labor. New contents are inserted but the old problems persisting, reinforcing the territorial inequalities.
O centro histórico de Lima, Peru: novos usos da Rua Jirón de La Unión
Authors: Gregório de Andrade Rita De Cássia , Morais Soares Maria Simone
Published: February 2018

A cidade de Lima foi fundada em 1535. Possui atualmente ao redor de 8.486.866 milhões de habitantes e apresenta problemas de organização espacial de grande complexidade, carecendo de distintos estudos para a compreensão desta realidade. O Centro Histórico de Lima é locus de políticas de gestão patrimonial desde a década de 1980. Nesse contexto, a Rua Jirón de la Unión, como a principal deste espaço urbano, merece ser analisada. Assim, o objetivo principal do estudo aqui exposto é analisar os novos usos da Rua Jirón de la Unión, no Centro Histórico de Lima. Os procedimentos metodológicos utilizados para a realização da pesquisa foram: levantamento bibliográfico, cartográfico, fotográfico e documental bem como trabalho de campo, para o levantamento do uso do solo e a observação da paisagem. Constatou-se o uso predominantemente comercial da atual Rua Jirón de la Unión.

Abstract

THE HISTORIC CENTRE OF LIMA, PERU: NEW USES OF JIRON DE LA UNION STREET

The city of Lima was founded in 1538. It currently has a population of about 8.486.866 and presents several complex problems of space organization, so that specific studies are needed to understand its reality. The Historical Center of Lima is locus of patrimonial management policies since the eighties. In this context, the Jirón de la Unión Street, the main of this urban space, deserves to be analyzed. The principal aim of this study is to analyze the new uses of Jirón De La Unión Street, in the historical center of Lima. The methodological procedures used to carry out this research were: bibliographical, cartographic, photographic and documentation surveys, together with outdoor researches to characterize the use of the soil and related landscape. A first observation was the predominant commercial use of the current Jirón de la Unión Street.
Geografia, paisagens e a felicidade
Authors: Aparecida de Souza Maria Adélia
Published: February 2018

O que a Geografia tem a dizer sobre a felicidade? Responder a esta questão e gerar polêmicas é o objetivo deste artigo. Ele também se constitui em um ensaio crítico sobre as práticas dos geógrafos enquanto repetidores dos ensinamentos oferecidos pela disciplina geográfica ainda bastante vinculada a uma perspectiva iluminista e positivista do ponto de vista metodológico. Esta repetição é devida a uma dificuldade de compreensão do mundo contemporâneo a partir das dinâmicas e da voracidade do tempo presente. A inspiração central deste artigo é provocada pela capacidade que a Geografia tem de discutir temas como a felicidade a partir dos usos do território e do conceito de espaço geográfico proposto pela Geografia Nova estabelecida por Milton Santos. Desvendar a felicidade a partir das paisagens e das dinâmicas do mundo contemporâneo se constitui na proposta central da discussão aqui feita, partindo da crítica às propostas de medidas estabelecidas por índices (IDH - Índice de Desenvolvimento Humano, Índice Brasil etc.) e metáforas (Sustentabilidade, Direitos Humanos, Segurança Alimentar, Inclusão Social etc.) que vêm sendo cada dia mais assumidos por pesquisas ditas científicas, no mundo todo.

Resumé

GÉOGRAPHIE, PAYSAGE ET LE BONHEUR

Qu’est-ce-que la Géographie peut dire à propôs du bonheur? Repondre à cette question est l’objetif de cet article. Il est aussi un essay critique sur les pratiques des géografes autant que reproducteurs des enseignements offerts pour une Géographie encore três attachée méthodologiquement à l’illuminisme et au positivisme. Cette reproduction est dûe à la dificulte pour la comprehension des dynamiques et voracité du temps present. L’inspiration centrale de cet article a éte provoquée par la possibilité qui a la Géographie de reflechir sur des thèmes tel que celui du bonheur. Cela peux se faire à partir des catégories analytiques comme le paysage, l’usage du territoire et le concept d’espace géographique compris en tant qu’une totalité dynamique, une indissociabilité entre systhèmes d’objets et systhèmes d’actions. Découvrir le bonheur à partir de la comprehension des pysages e des dynamiques du monde contemporain est au centre de la discussion ici proposée. Elle est faite à partir des “mesures” du bonheur produites à partir des índices (tels que l’IDH – Indice de Développement Humain, Indice Brésil, etc.) et des métaphores (Sustentabilité, Droits de l’Homme, Sécurité Alimentaire, Inclusion Sociale, etc.) qui, à chaque jour, sont plus adoptées par des recherches nonmées scientifiques, dans le monde entier.
Impacts and Uncertainties of +2°C of Climate Change and Soil Degradation on European Crop Calorie Supply
Authors: Balkovič Juraj , Skalský Rastislav , Folberth Christian , Khabarov Nikolay , Schmid Erwin , Madaras Mikuláš , Obersteiner Michael , van der Velde Marijn
Published: February 2018

Even if global warming is kept below +2°C, European agriculture will be significantly impacted. Soil degradation may amplify these impacts substantially and thus hamper crop production further. We quantify biophysical consequences and bracket uncertainty of +2°C warming on calories supply from 10 major crops and vulnerability to soil degradation in Europe using crop modeling. The Environmental Policy Integrated Climate (EPIC) model together with regional climate projections from the European branch of the Coordinated Regional Downscaling Experiment (EURO‐CORDEX) was used for this purpose. A robustly positive calorie yield change was estimated for the EU Member States except for some regions in Southern and South‐Eastern Europe. The mean impacts range from +30 Gcal ha−1 in the north, through +25 and +20 Gcal ha−1 in Western and Eastern Europe, respectively, to +10 Gcal ha−1 in the south if soil degradation and heat impacts are not accounted for. Elevated CO2 and increased temperature are the dominant drivers of the simulated yield changes in high‐input agricultural systems. The growth stimulus due to elevated CO2 may offset potentially negative yield impacts of temperature increase by +2°C in most of Europe. Soil degradation causes a calorie vulnerability ranging from 0 to 50 Gcal ha−1 due to insufficient compensation for nutrient depletion and this might undermine climate benefits in many regions, if not prevented by adaptation measures, especially in Eastern and North‐Eastern Europe. Uncertainties due to future potentials for crop intensification are about 2–50 times higher than climate change impacts.
Spatiotemporal Patterns of Precipitation‐Modulated Landslide Deformation From Independent Component Analysis of InSAR Time Series
Authors: Cohen‐Waeber J. , Bürgmann R. , Chaussard E. , Giannico C. , Ferretti A.
Published: February 2018

Long‐term landslide deformation is disruptive and costly in urbanized environments. We rely on TerraSAR‐X satellite images (2009–2014) and an improved data processing algorithm (SqueeSAR™) to produce an exceptionally dense Interferometric Synthetic Aperture Radar ground deformation time series for the San Francisco East Bay Hills. Independent and principal component analyses of the time series reveal four distinct spatial and temporal surface deformation patterns in the area around Blakemont landslide, which we relate to different geomechanical processes. Two components of time‐dependent landslide deformation isolate continuous motion and motion driven by precipitation‐modulated pore pressure changes controlled by annual seasonal cycles and multiyear drought conditions. Two components capturing more widespread seasonal deformation separate precipitation‐modulated soil swelling from annual cycles that may be related to groundwater level changes and thermal expansion of buildings. High‐resolution characterization of landslide response to precipitation is a first step toward improved hazard forecasting.
Delayed Poroelastic Triggering of the 2016 October Visso Earthquake by the August Amatrice Earthquake, Italy
Authors: Tung S. , Masterlark T.
Published: February 2018

Two months after the 2016 Amatrice earthquake (AE), a strong (~M6) earthquake (Visso earthquake, VE) struck the town Visso, Italy, 20 km north of the AE epicenter. Between these two events, the aftershocks migrated gradually toward to the VE epicenter at a rate of ~0.4 km/d, indicating propagation of pore pressure front. We use finite element models to simulate the postseismic fully coupled poroelastic response. The results show that the pore fluid flows (up to 50 nm/s) both horizontally and vertically into the VE hypocenter since the AE and destabilized the area with extra ~70% of Coulomb failure stress. Majority of nearby aftershocks (>80%) tend to cluster within the zones of coseismic depressurization where fluid flow converges. A maximum ΔCFS of ~35 kPa is calculated at the VE hypocenter during its rupture by a crustal permeability, 10–16 ± 0.7 m2, suggesting that an intermediately fractured crust allows maximum rupture tendency for the VE during poroelastic fluid recovery.
Climate Response to Negative Greenhouse Gas Radiative Forcing in Polar Winter
Authors: Flanner M. G. , Huang X. , Chen X. , Krinner G.
Published: February 2018

Greenhouse gas (GHG) additions to Earth's atmosphere initially reduce global outgoing longwave radiation, thereby warming the planet. In select environments with temperature inversions, however, increased GHG concentrations can actually increase local outgoing longwave radiation. Negative top of atmosphere and effective radiative forcing (ERF) from this situation give the impression that local surface temperatures could cool in response to GHG increases. Here we consider an extreme scenario in which GHG concentrations are increased only within the warmest layers of winter near‐surface inversions of the Arctic and Antarctic. We find, using a fully coupled Earth system model, that the underlying surface warms despite the GHG addition exerting negative ERF and cooling the troposphere in the vicinity of the GHG increase. This unique radiative forcing and thermal response is facilitated by the high stability of the polar winter atmosphere, which inhibit thermal mixing and amplify the impact of surface radiative forcing on surface temperature. These findings also suggest that strategies to exploit negative ERF via injections of short‐lived GHGs into inversion layers would likely be unsuccessful in cooling the planetary surface.
Radiation Weakens Idealized Midlatitude Cyclones
Authors: Schäfer Sophia A. K. , Voigt Aiko
Published: February 2018

Midlatitude cyclones are strongly affected by diabatic processes. While the importance of latent heating is well established, the role of radiation has received little attention. Here we address this question for idealized cyclones by performing baroclinic life cycle simulations in the global atmosphere model ICON with and without radiation, and with transparent clouds. Radiation substantially weakens the simulated cyclone: peak eddy kinetic energy reduces by 50%, and minimum storm central pressure increases by 17 hPa. An analysis of the Lorenz energy cycle shows that the radiative weakening is not due to changes in the large‐scale environment alone but involves radiative processes within the cyclone. In fact, radiation warms the lower tropospheric part of the cyclone's warm conveyor belt and cools the upper tropospheric part. We hypothesize that radiation weakens the cyclone by destroying midtropospheric potential vorticity in the warm conveyor belt.
Soil Susceptibility to Macropore Flow Across a Desert‐Oasis Ecotone of the Hexi Corridor, Northwest China
Authors: Zhang Yongyong , Zhao Wenzhi , He Jianhua , Fu Li
Published: February 2018

Macropore flow not only provides a fast pathway for water and solute transport and increases the risks of water and nutrient loss but also enhances soil aeration and groundwater recharge. However, macropore flow characteristics in irrigated oasis soils subject to continuous crop cultivation are poorly understood. This study was to investigate the effect of continuous cultivation on soil properties and macropore flow and to quantify the changes in macropore flow characteristics in an old oasis field (>50 years of cultivation, OOF), young oasis field (20 years, YOF), and adjacent uncultivated sandy area (0 year, USL) in Northwest China. Triplicate soil samples were collected from each site to investigate soil properties. Dye tracer experiments with also three replicates were conducted at each site. The degree of macropore flow (i.e., parameters of macropore flow) was highest at the OOF, intermediate at the YOF, and minimal at the USL. The macropore flow fraction (i.e., fraction of total infiltration flows through macropore flow pathways) at the OOF was 3.4 times greater than at the USL. The heterogeneous infiltration pattern at the OOF was dominated by macropore flow, while funnel flow was predominant at the USL. Long‐term irrigation with silt‐laden river water has increased silt + clay contents of the oasis soils. Irrigation and high‐input crop cultivation also increased organic matter. These changes in soil properties contributed to the interaggregate voids formation. The conversion of native desert soils to irrigated croplands increases the degree of macropore flow, which might enhance groundwater recharge in the desert‐oasis ecotone.
Design, Fabrication, and Characterization of Porous Yttria‐Stabilized Zirconia Ceramics for Hot Gas Filtration Applications
Authors: Shahini Shayan , Judge William D. , Tam Jason , Azimi Gisele
Published: February 2018

Hot gas filtration is a lucrative target for a number of high temperature industrial operations, but new materials must be developed to withstand intense high temperature conditions. Here, the authors put the emphasis on porous yttria‐stabilized zirconia (YSZ) ceramics for hot gas filtration, owing to their high thermodynamic stability and toughness. The authors design and fabricate porous YSZ ceramics using a pore‐forming inclusion technique, where a polymeric pore former is mixed and compacted with YSZ powder. After burning off, the polymer leaves behind a controlled amount of porosity before sintering commenced. The authors systematically investigate the sintering temperature, polymer particle size, and polymer‐to‐ceramic ratio to optimize the open porosity, pore size, gas permeability, and hardness of porous YSZ ceramics. The authors then evaluate the performance of porous YSZ ceramics under industrial conditions by cyclic heating/cooling testing and high temperature exposure testing. The authors show, for the first time, porous YSZ ceramics can perform in hot gas filtration applications at 1400 °C for extended thermal cycling or at 1700 °C for limited periods of time.
The Solid Flame Phenomenon: A Novel Perspective
Authors: Mukasyan Alexander S. , Shuck Christopher E. , Pauls Joshua M. , Manukyan Khachatur V. , Moskovskikh Dmitry O. , Rogachev Alexander S.
Published: February 2018

In this paper, the authors overview previous publications and present novel results related to self‐sustained solid‐state reactions: the solid flame. Due to recent advances in the fabrication of nano‐structured reactive media, this phenomenon, which is first reported fifty years ago, has found a new perspective for a wide variety of exothermic systems. These fundamental findings permit novel routes for synthesis of advanced engineering materials with controlled microstructure, as well as for design of high‐energy density systems with tuned parameters for energy release.
Interaction of NiAl Intermetallic During SHS Synthesis with Ta Substrate
Authors: Shchukin Alexander S. , Vrel Dominique , Sytschev Alexander E.
Published: February 2018

NiAl intermetallic is obtained during exothermic reaction of mechanically activated Ni and Al powders, taking place by thermal explosion (TE) mode of self‐propagating high‐temperature synthesis (SHS). When a layer of Ni–Al blend is placed in contact with Ta substrate, the heat this exothermic reaction results in reaction multilayer with composition corresponding to intermetallic predicted by Ta–Ni–Al ternary phase diagram. The used approach is proposed for processing of oxidation resistant coating on Ta as well as for joining of parts from ta and its alloys.
All‐Inorganic CsPbI3 Perovskite Phase‐Stabilized by Poly(ethylene oxide) for Red‐Light‐Emitting Diodes
Authors: Jeong Beomjin , Han Hyowon , Choi Yung Ji , Cho Sung Hwan , Kim Eui Hyuk , Lee Seung Won , Kim Jong Sung , Park Chanho , Kim Dongho , Park Cheolmin
Published: February 2018

Despite the excellent photoelectronic properties of the all‐inorganic cesium lead iodide (CsPbI3) perovskite, which does not contain volatile and hygroscopic organic components, only a few CsPbI3 devices are developed mainly owing to the frequent formation of an undesirable yellow δ‐phase at room temperature. Herein, it is demonstrated that a small quantity of poly(ethylene oxide) (PEO) added to the precursor solution effectively inhibits the formation of the yellow δ‐phase during film preparation, and promotes the development of a black α‐phase at a low crystallization temperature. A systematic study reveals that a thin, dense, pinhole‐free CsPbI3 film is produced in the α‐phase and is stabilized with PEO that effectively reduces the grain size during crystallization. A thin α‐phase CsPbI3 film with excellent photoluminescence is successfully employed in a light‐emitting diode with an inverted configuration of glass substrate/indium tin oxide/zinc oxide/poly(ethyleneimine)/α‐CsPbI3/poly(4‐butylphenyl‐diphenyl‐amine)/WO3/Al, yielding the characteristic red emission of the perovskite film at 695 nm with brightness, external quantum efficiency, and emission band width of ≈101 cd m−2, 1.12%, and 32 nm, respectively.
Low‐Voltage, Optoelectronic CH3NH3PbI3−xClx Memory with Integrated Sensing and Logic Operations
Authors: Zhou Feichi , Liu Yanghui , Shen Xinpeng , Wang Mengye , Yuan Fang , Chai Yang
Published: February 2018

Nonvolatile optoelectronic memories integrated with the functions of sensing, data storage, and data processing are promising for the potential Internet of things (IoT) applications. To meet the requirements of IoT devices, multifunctional memory devices with low power consumption and secure data storage are highly desirable. This study demonstrates an optoelectronic resistive switching memory integrated with sensing and logic operations by adopting organic–inorganic hybrid CH3NH3PbI3−xClx perovskites, which possess unusual defect physics and excellent light absorption. The CH3NH3PbI3−xClx cell exhibits low operation voltage of 0.1 V with the assistance of light illumination, long‐term retention property, and multiple resistance states. Its unique optoelectronic characteristics enable to perform logic operation for inputting one electrical pulse and one optical signal, and detect the coincidence of electrical and optical signal as well. This design provides possibilities for smart sensor in IoT application.
Stable Metal–Organic Frameworks: Design, Synthesis, and Applications
Authors: Yuan Shuai , Feng Liang , Wang Kecheng , Pang Jiandong , Bosch Matheiu , Lollar Christina , Sun Yujia , Qin Junsheng , Yang Xinyu , Zhang Peng , Wang Qi , Zou Lanfang , Zhang Yingmu , Zhang Liangliang , Fang Yu , Li Jialuo , Zhou Hong‐Cai
Published: February 2018

Metal–organic frameworks (MOFs) are an emerging class of porous materials with potential applications in gas storage, separations, catalysis, and chemical sensing. Despite numerous advantages, applications of many MOFs are ultimately limited by their stability under harsh conditions. Herein, the recent advances in the field of stable MOFs, covering the fundamental mechanisms of MOF stability, design, and synthesis of stable MOF architectures, and their latest applications are reviewed. First, key factors that affect MOF stability under certain chemical environments are introduced to guide the design of robust structures. This is followed by a short review of synthetic strategies of stable MOFs including modulated synthesis and postsynthetic modifications. Based on the fundamentals of MOF stability, stable MOFs are classified into two categories: high‐valency metal–carboxylate frameworks and low‐valency metal–azolate frameworks. Along this line, some representative stable MOFs are introduced, their structures are described, and their properties are briefly discussed. The expanded applications of stable MOFs in Lewis/Brønsted acid catalysis, redox catalysis, photocatalysis, electrocatalysis, gas storage, and sensing are highlighted. Overall, this review is expected to guide the design of stable MOFs by providing insights into existing structures, which could lead to the discovery and development of more advanced functional materials.
Reassembly of 89Zr‐Labeled Cancer Cell Membranes into Multicompartment Membrane‐Derived Liposomes for PET‐Trackable Tumor‐Targeted Theranostics
Authors: Yu Bo , Goel Shreya , Ni Dalong , Ellison Paul A. , Siamof Cerise M. , Jiang Dawei , Cheng Liang , Kang Lei , Yu Faquan , Liu Zhuang , Barnhart Todd E. , He Qianjun , Zhang Han , Cai Weibo
Published: February 2018

Nanoengineering of cell membranes holds great potential to revolutionize tumor‐targeted theranostics, owing to their innate biocompatibility and ability to escape from the immune and reticuloendothelial systems. However, tailoring and integrating cell membranes with drug and imaging agents into one versatile nanoparticle are still challenging. Here, multicompartment membrane‐derived liposomes (MCLs) are developed by reassembling cancer cell membranes with Tween‐80, and are used to conjugate 89Zr via deferoxamine chelator and load tetrakis(4‐carboxyphenyl) porphyrin for in vivo noninvasive quantitative tracing by positron emission tomography imaging and photodynamic therapy (PDT), respectively. Radiolabeled constructs, 89Zr‐Df‐MCLs, demonstrate excellent radiochemical stability in vivo, target 4T1 tumors by the enhanced permeability and retention effect, and are retained long‐term for efficient and effective PDT while clearing gradually from the reticuloendothelial system via hepatobiliary excretion. Toxicity evaluation confirms that the MCLs do not impose acute or chronic toxicity in intravenously injected mice. Additionally, 89Zr‐labeled MCLs can execute rapid and highly sensitive lymph node mapping, even for deep‐seated sentinel lymph nodes. The as‐developed cell membrane reassembling route to MCLs could be extended to other cell types, providing a versatile platform for disease theranostics by facilely and efficiently integrating various multifunctional agents.
Inherently Eu2+/Eu3+ Codoped Sc2O3 Nanoparticles as High‐Performance Nanothermometers
Authors: Pan Yue , Xie Xiaoji , Huang Qianwen , Gao Chao , Wang Yangbo , Wang Lingxiao , Yang Bingxiao , Su Haiquan , Huang Ling , Huang Wei
Published: February 2018

Luminescent nanothermometers have shown competitive superiority for contactless and noninvasive temperature probing especially at the nanoscale. Herein, we report the inherently Eu2+/Eu3+ codoped Sc2O3 nanoparticles synthesized via a one‐step and controllable thermolysis reaction where Eu3+ is in‐situ reduced to Eu2+ by oleylamine. The stable luminescence emission of Eu3+ as internal standard and the sensitive response of Eu2+ emission to temperature as probe comprise a perfect ratiometric nanothermometer with wide‐range temperature probing (77–267 K), high repeatability (>99.94%), and high relative sensitivity (3.06% K–1 at 267 K). The in situ reduction of Eu3+ to Eu2+ ensures both uniform distribution in the crystal lattice and simultaneous response upon light excitation of Eu2+/Eu3+. To widen this concept, Tb3+ is codoped as additional internal reference for tunable temperature probing range.
Dynamic Plasmonic Color Generation Based on Phase Transition of Vanadium Dioxide
Authors: Shu Fang‐Zhou , Yu Fang‐Fang , Peng Ru‐Wen , Zhu Ying‐Ying , Xiong Bo , Fan Ren‐Hao , Wang Zheng‐Han , Liu Yongmin , Wang Mu
Published: February 2018

Plasmonic color filtering and color printing have attracted considerable attention in recent years due to their supreme performance in display and imaging technologies. Although various color‐related devices are designed, so far very few studies have touched the topic of dynamic color generation. In this article, dynamic color generation is demonstrated by integrating plasmonic nanostructures with vanadium dioxide based on its tunable optical properties through insulator–metal transition. Periodic arrays of silver nanodisks on a vanadium dioxide film are fabricated to realize different colors, relying on the excitation of localized and propagating surface plasmons, and Wood's anomaly. By tuning spatial periodicity of the arrays and diameter of the silver nanodisks, various colors can be achieved across the entire visible spectrum. Further, using insulator–metal transition of vanadium dioxide, the colors can be actively tuned by varying temperature. The approach of dynamic color generation based on the phase transition of vanadium dioxide can easily realize diverse color patterns, which makes it beneficial for display and imaging technology with distinct advantages of multifunctionality, flexibility, and high efficiency.
Challenges in Developing Electrodes, Electrolytes, and Diagnostics Tools to Understand and Advance Sodium‐Ion Batteries
Authors: Xu Gui‐Liang , Amine Rachid , Abouimrane Ali , Che Haiying , Dahbi Mouad , Ma Zi‐Feng , Saadoune Ismael , Alami Jones , Mattis Wenjuan Liu , Pan Feng , Chen Zonghai , Amine Khalil
Published: February 2018

Considering the natural abundance and low cost of sodium resources, sodium‐ion batteries (SIBs) have received much attention for large‐scale electrochemical energy storage. However, smart structure design strategies and good mechanistic understanding are required to enable advanced SIBs with high energy density. In recent years, the exploration of advanced cathode, anode, and electrolyte materials, as well as advanced diagnostics have been extensively carried out. This review mainly focuses on the challenging problems for the attractive battery materials (i.e., cathode, anode, and electrolytes) and summarizes the latest strategies to improve their electrochemical performance as well as presenting recent progress in operando diagnostics to disclose the physics behind the electrochemical performance and to provide guidance and approaches to design and synthesize advanced battery materials. Outlook and perspectives on the future research to build better SIBs are also provided.
Elucidation of the Sodium‐Storage Mechanism in Hard Carbons
Authors: Bai Panxing , He Yongwu , Zou Xiaoxi , Zhao Xinxin , Xiong Peixun , Xu Yunhua
Published: February 2018

Hard carbons (HCs) are the most promising candidate anode materials for emerging Na‐ion batteries (NIBs). HCs are composed of misaligned graphene sheets with plentiful nanopores and defects, imparting a complex correlation between its structure and sodium‐storage behavior. The currently debated mechanism of Na+‐ion insertion in HCs hinders the development of high‐performance NIBs. In this article, ingenious and reliable strategies are used to elaborate the correlation between the structure and electrochemical performance and further illuminate the sodium‐storage mechanism in HCs. First, filling sulfur into the micropores of HCs can remove the low‐voltage plateau, providing solid evidence for its association with the pore‐filling mechanism. Along with the decreased concentration of defects/heteroatoms at higher treatment temperature, the reduced sloping capacity confirms the adsorption mechanism in the sloping region. Finally, the similar sodium‐insertion behaviors of HCs with ether‐based and ester‐based electrolytes indicate that no Na+ ions intercalate between the graphene layers. The determined adsorption‐pore‐filling mechanism encourages the design of more efficient HC anode materials with high capacity for high‐energy NIBs.
The Role of Active Oxide Species for Electrochemical Water Oxidation on the Surface of 3d‐Metal Phosphides
Authors: Liu Kaili , Wang Fengmei , He Peng , Shifa Tofik Ahmed , Wang Zhenxing , Cheng Zhongzhou , Zhan Xueying , He Jun
Published: February 2018

Transition metal phosphides (TMPs) have recently been utilized as promising electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The metal oxides or hydroxides formed on their surface during the OER process are hypothesized to play an important role. However, their exact role is yet to be elucidated. Here unambiguous justification regarding the active role of oxo(hydroxo) species on O‐Ni(1−x)FexP2 nanosheet with pyrite structure is shown. These O‐Ni(1−x)FexP2 (x = 0.25) nanosheets demonstrate greatly improved OER performance than their corresponding hydroxide and oxide counterparts do. From density function theory (DFT) calculations, it is found that the introduction of iron into the pyrite‐phased NiP2 alters OER steps occurred on the surface. Notably, the partially oxidized surface of O‐Ni(1−x)FexP2 nanosheets is vital to improve the local environment and accelerate the reaction steps. This study sheds light on the OER mechanism of the 3d TMP electrocatalyst and opens up a way to develop efficient and low‐cost electrocatalysts.
A novel homozygous AP4B1 mutation in two brothers with AP‐4 deficiency syndrome and ocular anomalies
Authors: Accogli Andrea , Hamdan Fadi F. , Poulin Chantal , Nassif Christina , Rouleau Guy A. , Michaud Jacques L. , Srour Myriam
Published: February 2018

Adaptor protein complex‐4 (AP‐4) is a heterotetrameric protein complex which plays a key role in vesicle trafficking in neurons. Mutations in genes affecting different subunits of AP‐4, including AP4B1, AP4E1, AP4S1, and AP4M1, have been recently associated with an autosomal recessive phenotype, consisting of spastic tetraplegia, and intellectual disability (ID). The overlapping clinical picture among individuals carrying mutations in any of these genes has prompted the terms “AP‐4 deficiency syndrome” for this clinically recognizable phenotype. Using whole‐exome sequencing, we identified a novel homozygous mutation (c.991C>T, p.Q331*, NM_006594.4) in AP4B1 in two siblings from a consanguineous Pakistani couple, who presented with severe ID, progressive spastic tetraplegia, epilepsy, and microcephaly. Sanger sequencing confirmed the mutation was homozygous in the siblings and heterozygous in the parents. Similar to previously reported individuals with AP4B1 mutations, brain MRI revealed ventriculomegaly and white matter loss. Interestingly, in addition to the typical facial gestalt reported in other AP‐4 deficiency cases, the older brother presented with congenital left Horner syndrome, bilateral optic nerve atrophy and cataract, which have not been previously reported in this condition. In summary, we report a novel AP4B1 homozygous mutation in two siblings and review the phenotype of AP‐4 deficiency, speculating on a possible role of AP‐4 complex in eye development.
Potential role for emergency physicians with endoscopy training in the treatment of upper gastrointestinal hemorrhage: a retrospective observational study
Authors: Kobe Yoshiro , Oami Takehiko , Hashida Tomoaki , Tateishi Yoshihisa
Published: February 2018

Aim

Urgent endoscopy is essential in gastrointestinal (GI) bleeding. Emergency physicians with endoscopy training treat patients with GI bleeding in our hospital. We compared the management and clinical outcomes of GI bleeding cases between those treated by an emergency physician (EP) and those treated by a non‐emergency physician (NEP; e.g., gastroenterologist or general surgeon).

Methods

We undertook a retrospective chart review of upper GI bleeding cases treated using endoscopy in the emergency department between 2012 and 2014. We examined patients characteristics, endoscopic findings, hemostatic procedures, need for transfusion, rebleeding and adverse events, length of hospital stay, and mortality.

Results

The EP group included 33 patients (39%) and the NEP group included 51 (61%). Patient characteristics and diseases did not differ between the groups. The EP group underwent urgent endoscopy more often (100% versus 86%, P = 0.04). Procedure times were not statistically different between the groups. The EP group had fewer hemostatic procedures (42% versus 65%, P = 0.04). Transfusion requirements were lower in the EP group (0.5 U versus 2.1 U, P = 0.006). There were no statistical differences in rebleeding and adverse events. The length of hospital stay was shorter (8 versus 11 days, P = 0.03) and the in‐hospital mortality rate was lower in the EP group (0% versus 13.7%, P = 0.04).

Conclusion

Short‐term outcomes in GI bleeding cases managed by emergency physicians with endoscopy training were comparable to those by gastroenterologists and general surgeons. However, the extent of endoscopic training and experience emergency physicians should have remains unclear.
Barium as Honorary Transition Metal in Action: Experimental and Theoretical Study of Ba(CO)+ and Ba(CO)−
Authors: Wu Xuan , Zhao Lili , Jiang Dandan , Fernández Israel , Berger Robert , Zhou Mingfei , Frenking Gernot
Published: February 2018

Ba(CO)+ and Ba(CO)− have been produced and isolated in a low‐temperature neon matrix. The observed C−O stretching wavenumber for Ba(CO)+ of 1911.2 cm−1 is the most red‐shifted value measured for any metal carbonyl cations, indicating strong π backdonation of electron density from Ba+ to CO. Quantum chemical calculations indicate that Ba(CO)+ has a 2Π reference state, which correlates with the 2D(5d1) excited state of Ba+ that comprises significant Ba+(5dπ1)→CO(π* LUMO) backbonding, letting the Ba(CO)+ complex behave like a conventional transition‐metal carbonyl. A bonding analysis shows that the π backdonation in Ba(CO)+ is much stronger than the Ba+(5dσ/6s)←CO(HOMO) σ donation. The Ba+ cation in the 2D(5d1) excited state is a donor rather than an acceptor. Covalent bonding in the radical anion Ba(CO)− takes place mainly through Ba(5dπ)←CO−(π* SOMO) π donation and Ba(5dσ/6s)←CO−(HOMO) σ donation. The most important valence functions at barium in Ba(CO)+ cation and Ba(CO)− anion are the 5d orbitals.
Highly Stable Aqueous Zinc‐Ion Storage Using a Layered Calcium Vanadium Oxide Bronze Cathode
Authors: Xia Chuan , Guo Jing , Li Peng , Zhang Xixiang , Alshareef Husam N.
Published: February 2018

Cost‐effective aqueous rechargeable batteries are attractive alternatives to non‐aqueous cells for stationary grid energy storage. Among different aqueous cells, zinc‐ion batteries (ZIBs), based on Zn2+ intercalation chemistry, stand out as they can employ high‐capacity Zn metal as the anode material. Herein, we report a layered calcium vanadium oxide bronze as the cathode material for aqueous Zn batteries. For the storage of the Zn2+ ions in the aqueous electrolyte, we demonstrate that the calcium‐based bronze structure can deliver a high capacity of 340 mA h g−1 at 0.2 C, good rate capability, and very long cycling life (96 % retention after 3000 cycles at 80 C). Further, we investigate the Zn2+ storage mechanism, and the corresponding electrochemical kinetics in this bronze cathode. Finally, we show that our Zn cell delivers an energy density of 267 W h kg−1 at a power density of 53.4 W kg−1.
Synthesis of Alternating Donor–Acceptor Ladder‐Type Molecules and Investigation of Their Multiple Charge‐Transfer Pathways
Authors: Cai Zhengxu , Zhang Na , Awais Mohammad A. , Filatov Alexander S. , Yu Luping
Published: February 2018

We describe the synthesis as well as the optical and charge‐transport properties of a series of donor–acceptor (D‐A) ladder‐type heteroacenes. These molecules are stable, soluble, and contain up to 24 fused rings. Structural analyses indicated that the backbones of S 10r and Se 10r are bent in single crystals. The three 10‐ring heteroacenes were functionalized with thiol anchoring groups and used for single‐molecular conductance measurements. The highest conductance was observed for molecular wires containing a benzoselenadiazole (BSD) moiety, which exhibits the narrowest band gap. Multiple charge‐transport pathways were observed in molecular wires containing either benzothiadiazole (BTD) or BSD. The conductance is a complex function of both energy gap and orbital alignment.
A Smart Superwetting Surface with Responsivity in Both Surface Chemistry and Microstructure
Authors: Zhang Dongjie , Cheng Zhongjun , Kang Hongjun , Yu Jianxin , Liu Yuyan , Jiang Lei
Published: February 2018

Recently, smart surfaces with switchable wettability have aroused much attention. However, only single surface chemistry or the microstructure can be changed on these surfaces, which significantly limits their wetting performances, controllability, and applications. A new surface with both tunable surface microstructure and chemistry was prepared by grafting poly(N‐isopropylacrylamide) onto the pillar‐structured shape memory polymer on which multiple wetting states from superhydrophilicity to superhydrophobicity can be reversibly and precisely controlled by synergistically regulating the surface microstructure and chemistry. Meanwhile, based on the excellent controllability, we also showed the application of the surface as a rewritable platform, and various gradient wettings can be obtained. This work presents for the first time a surface with controllability in both surface chemistry and microstructure, which starts some new ideas for the design of novel superwetting materials.
Ion‐Selective Electrodes Based on Hydrophilic Ionophore‐Modified Nanopores
Authors: Papp Soma , Jágerszki Gyula , Gyurcsányi Róbert E.
Published: February 2018

We report the synthesis and analytical application of the first Cu2+‐selective synthetic ion channel based on peptide‐modified gold nanopores. A Cu2+‐binding peptide motif (Gly‐Gly‐His) along with two additional functional thiol derivatives inferring cation‐permselectivity and hydrophobicity was self‐assembled on the surface of gold nanoporous membranes comprising of about 5 nm diameter pores. These membranes were used to construct ion‐selective electrodes (ISEs) with extraordinary Cu2+ selectivities, approaching six orders of magnitude over certain ions. Since all constituents are immobilized to a supporting nanoporous membrane, their leaching, that is a ubiquitous problem of conventional ionophore‐based ISEs was effectively suppressed.
Formation of a Highly Reactive Cobalt Nanocluster Crystal within a Highly Negatively Charged Porous Coordination Cage
Authors: Fang Yu , Xiao Zhifeng , Li Jialuo , Lollar Christina , Liu Lujia , Lian Xizhen , Yuan Shuai , Banerjee Sayan , Zhang Peng , Zhou Hong‐Cai
Published: February 2018

Earth‐abundant first‐row transition‐metal nanoclusters (NCs) have been extensively investigated as catalysts. However, their catalytic activity is relatively low compared with noble metal NCs. Enhanced catalytic activity of cobalt NCs can be achieved by encapsulating Co NCs in soluble porous coordination cages (PCCs). Two cages, PCC‐2a and 2b, possess almost identical cavity in shape and size, while PCC‐2a has five times more net charges than PCC‐2b. Co2+ cations were accumulated in PCC‐2a and reduced to ultra‐small Co NCs in situ, while for PCC‐2b, only bulky Co particles were formed. As a result, Co NCs@PCC‐2a accomplished the highest catalytic activity in the hydrolysis of ammonium borane among all the first‐row transition‐metals NCs. Based on these results, it is envisioned that confining in the charged porous coordination cage could be a novel route for the synthesis of ultra‐small NCs with extraordinary properties.