bluuebunny/crossref_metadata_2025 huggingface dataset:
Espacios públicos como áreas sensibles en el Centro Histórico de Quito
Authors: Cruz-Cabrera Marianela
Published: December 2017

La ciudad tradicional y dentro de ella los centros históricos se constituyen en áreas muy sensibles de los contextos urbanos. Lugares que han sufrido transformaciones y en la actualidad son protagonistas de los efectos de la degradación de sus edificaciones, la segregación, la excesiva sobreexplotación, además de la agresión del tráfico automotor para lo cual no fueron diseñadas. El diseño de sus espacios públicos de conjunto con el paisaje urbano histórico actúan sin lugar a dudas como criterios fundamentales para estructurar y ordenar el uso y funcionamiento de estos lugares. El presente trabajo centra su atención en el área más central y asociada al período fundacional de la ciudad de Quito, específicamente, el Centro Histórico (CH). El objetivo a alcanzar será mostrar problemáticas existentes a nivel del CHQ en general y en el área de estudio en específico, donde se continúa dando prioridad al tráfico automotor, la inseguridad se incrementa y sus dinámicas de uso continúan regidas por la economía terciaria y la informalidad, existe desarticulación de espacios públicos de alto valor simbólico, patrimonial e identitarios, así como la amenaza de que esta importante zona se convierta en un lugar meramente turístico y escenográfico. Se plantean posibles acciones que contribuyan a consolidar una red de espacios interconectados de lugares donde predominen los intereses del peatón Los centros históricos, su paisaje y la riqueza patrimonial que lo caracteriza se constituyen hoy en día en un valioso recurso, un derecho ciudadano en el cual hemos de apoyarnos para alcanzar la meta de la ciudad sostenible.
Personalidade do Professor Doutor Aureliano da Fonseca
Authors: Poiares Baptista A.
Published: December 2017

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Carcinoma Espinhocelular Avançado do Lábio, do Diagnóstico ao Tratamento
Authors: Mendes Abreu João
Published: December 2017

O carcinoma espinhocelular cutâneo é uma neoplasia cutânea não melanocitica, potencialmente fatal, que resulta da proliferação descontrolada dos queratinócitos. Predominante na cabeça e pescoço, esta surge preferencialmente em zonas expostas ao sol. O diagnóstico tem por base a apresentação clínica da lesão, idealmente através da dermatoscopia, necessitando, porém, da avaliação histológica para a definição do mesmo.Este trabalho reporta o caso de um homem de 71 anos referenciado por lesão do lábio inferior, hiperqueratósica e infiltrativa, sugestiva de carcinoma espinhocelular cutâneo. Confirmado a suspeita procedeu-se à excisão radical da lesão, cujo defeito resultante ocupava 70% do comprimento do lábio inferior na sua porção mediana, em espessura total, tendo-se recorrido à reconstrução com recurso aos retalhos de deslizamento e rotação descritos por Karapandzic. O resultado final caracterizou-se por cicatrizes a preencherem os sulcos fisiológicos e pela manutenção da continência oral, bem como da sensibilidade e mobilidade labiais.
Fotossensibilidade Induzida por Fármacos
Authors: Gouveia Miguel , Gameiro Ana , Coutinho Inês , Gonçalo Margarida
Published: December 2017

A fotossensibilidade induzida por fármacos traduz uma resposta cutânea anormal à luz em indivíduos expostos a um fármaco, os quais, na sua ausência, tolerariam o mesmo grau de fotoexposição. Pode ocorrer como uma reação aguda ou retardada, assumindo características clínicas polimórficas que variam desde a queimadura solar exagerada até aspectos de fotoonicólise, pseudo- -porfíria, pigmentação, eczema agudo e lúpus eritematoso cutâneo. Os autores descrevem os fármacos mais frequentemente envolvidos neste tipo de reações e as formas clínicas mais frequentes e discutem o possível contributo destes fármacos na potenciação da fotocarcinogénese. O reconhecimento d estes padrões clínicos de fotossensibilidade e dos fármacos responsáveis é fundamental para a evicção do fármaco causal e consequente melhoria ou resolução da reação de fotossensibilidade.
Sirolimus e Prevenção Primária de Cancro Cutâneo Não-melanoma em Transplantados Renais – Um Estudo Retrospetivo
Authors: Pinho André , Aguiar Brigite , Brites Maria Manuel , Vieira Ricardo , Alves Rui , Figueiredo Américo
Published: December 2017

Introdução: A imunossupressão desempenha um papel central na patogénese do cancro cutâneo, em transplantados renais. Recentemente tem sido estudado o potencial do sirolimus na redução da incidência de cancro cutâneo não-melanoma nesta população.Objetivo: Analisar a relação entre os esquemas imunossupressores de manutenção iniciais e o desenvolvimento de cancro cutâneo não-melanoma – carcinoma espinhocelular e carcinoma basocelular – em transplantados renais.Métodos: Análise retrospetiva dos registos clínicos de doentes submetidos a transplante renal entre os anos 2002 e 2012 e que vieram posteriormente a ser observados no nosso Serviço de Dermatologia. Os transplantados renais foram divididos em três grupos, de acordo com o esquema imunossupressor de manutenção inicial: grupo A (à base de sirolimus), grupo B (à base de tacrolimus), grupo C (à base de ciclosporina).Resultados: Dos 188 transplantados renais estudados, 24,5% (n=46) foram diagnosticados com 83 cancro cutâneo não-melanoma (42 carcinoma basocelular e 41 carcinoma espinhocelular). Não houve diferenças na sobrevivência livre do primeiro cancro cutâneo não-melanoma ou do primeiro carcinoma basocelular entre os grupos. A sobrevivência livre de primeiro carcinoma espinhocelular foi significativamente maior no grupo A (média 10,7 anos), quando comparado com os grupos B (média 7,48 anos) e C (média 8,29 anos). O hazard ratio bruto de carcinoma espinhocelular foi significativamente superior nos grupos C (7,74, p = 0,05) e B (9,02, p = 0,03), em comparação com o grupo A. Contudo, após ajuste para a idade à data de transplante, estes valores perderam significado estatístico.Conclusão: Ainda que o switch para sirolimus esteja descrito como benéfico na prevenção secundária de carcinoma espinhocelular em transplantados renais, a sua utilização ab initio não pareceu apresentar o mesmo efeito protetor.
Triquilemoma Desmoplástico em Nevo Sebáceo do Couro Cabeludo
Authors: Tavares-Bello Rui , Tellechea Óscar , Fernandes Sónia
Published: December 2017

Descrito originalmente por Jadassohn em 1895, foi apenas em 1932 que a designação “nevo sebáceo” foi introduzida, por Robinson. Trata-se de um hamartoma congénito relativamente prevalente que, classicamente, evolui por fases de crescimento e maturação (classicamente estão descritas 3 fases: infância <12; adolescência 12-18; adultos >18) e que, do 4º ao 7º decénios pode originar, em 10-30% dos casos), várias neoplasias epiteliais. Muito raramente reportados neste contexto, os triquilemomas são tumores anexiais benignos que se originam ou diferenciam no epitélio da bainha radicular externa folicular. Habitualmente solitários, podem apresentar-se clinicamente como pápulas translúcidas ou queratósicas faciais, em particular na proximidade da pirâmide nasal e dos lábios. A rara variante histológica “triquilemoma desmoplásico” pode simular clinicamente basaliomas (CBC), carcinomas espinhocelulares (CEC), nevos intradérmicos, verrugas virais, cornos cutâneos ou hiperplasias sebáceas e, histologicamente, evocar variantes desmoplásicas de CBCs, CECs e de carcinomas triquilémicos. É apresentado caso de doente eurocaucasiano de 56 anos de idade que apresentava pápulas e nódulos translúcidos assintomáticos, desenvolvidos num nevo sebáceo do couro cabeludo. O estudo histológico revelou uma proliferação lobular com as características clássicas do triquilemoma desmoplásico no seio de um hamartoma sebáceo. O caso é ilustrado iconograficamente e a literatura relevante é sumariamente revista.
Unilateral Lichen Aureus in a Child - Case Report
Authors: Freitas de Oliveira Góes Heliana , Troyano de Castro Mendes Marília , Falci Loures Aline , Lobato Quattrino Ada , Dos Santos Lima Caren , Pantaleão Luciana
Published: December 2017

Lichen aureus is a subtype of a chronic benign pigmented purpuric dermatosis of unknown etiology. It shows predilection for lower limbs and generally affects young adults and, less often, children. We report a case of lichen aureus with a unilateral presentation in a child.
O Nevo Displásico
Authors: Brás Susana , Gouveia Ana Isabel , Teixeira Ana Isabel , Oliveira André Laureano , Soares Almeida Luis Miguel
Published: December 2017

O nevo melanocítico displásico é uma entidade controversa. Os autores realizaram uma revisão da literatura com o objectivo de tentar esclarecer o que é um nevo displásico, quais os critérios actuais para o seu diagnóstico, qual a sua relação com o risco de melanoma e como abordar o doente com história de nevos displásicos.
Uma Causa Rara de Púrpura Palpável: Poliangeíte Granulomatosa Eosinofílica
Authors: Teixeira Ana Isabel , Estanislau Correia Teresa , Soares-de-Almeida Luis
Published: December 2017

A poliangeíte granulomatosa eosinofílica é uma vasculite de pequenos e médios vasos incluída no grupo das vasculites associadas a anticorpos anti-citoplasma de neutrófilos. É uma doença rara caracterizada pela presença de vasculite em associação com asma e eosinofilia. Os autores relatam o caso de um doente de 67 anos de idade, com quadro de púrpura palpável dos membros superiores, inferiores e abdómen, com um mês de evolução. Associava queixas de tosse seca desde há um ano com agravamento da frequência e, aparecimento de hemoptises no último mês. O estudo complementar permitiu efectuar o diagnóstico de poliangeite granulomatosa eosinofílica e o doente foi medicado com prednisolona até remissão da doença, seguido de esquema de redução progressiva da dose e início de terapêutica de manutenção com azatioprina, sem recidiva após um ano de follow-up.
Vitamina D – Perspetivas Atuais
Authors: Catarino Alexandre Miroux , Claro Cristina , Viana Isabel
Published: December 2017

A vitamina D tem como efeito biológico principal a promoção da mineralização óssea e a regulação da homeostasia do metabolismo cálcio-fósforo. A sua função biológica extra-esqueleto tem sido amplamente estudada e o seu défice associado a risco aumentado para diversas patologias, nomeadamente autoimunes, neoplásicas, cardiovasculares e neurológicas, entre outras. No entanto, esta mantém-se uma área de controvérsia e ficam por demonstrar a relação causa-efeito entre deficiência de vitamina D e patologia não esquelética, e o benefício da suplementação com este objetivo. Nos indivíduos em risco de hipovitaminose a suplementação é segura, barata e com benefício demonstrado na prevenção de fraturas e quedas. É feita uma abordagem da síntese, metabolismo e modo de ação da vitamina D. Faz-se uma revisão sumária da fisiopatologia da vitamina D na pele - a influência da pigmentação cutânea e do uso de fotoproteção na sua síntese, e a sua relação com as dermatoses mais frequentes.
Diagnóstico laboratorial de infeção VIH em adultos
Authors: Trigo Diva , Costa João Borges
Published: December 2017

Ao longo dos últimos 35 anos, grandes progressos foram alcançados em termos de prevenção, diagnóstico e tratamento de infeção VIH, com redução da incidência de infeção em Portugal, na última década. Ainda assim, continua a existir uma taxa elevada de doentes com diagnóstico tardio, com consequências individuais e populacionais. Este artigo tem como objectivos: apresentar um ponto de situação da infeção VIH em Portugal, rever brevemente a evolução natural da infeção e explicitar o mais recente algoritmo de diagnóstico de infeção VIH, revisto em 2014, reforçando a necessidade de manter um elevado nível de suspeição clínica para o diagnóstico precoce de infeção.
Infeção Cutânea por Citomegalovírus em Doente com Infecção VIH/SIDA
Authors: Banquimane Marcelo Jaime , Dos Santos Monteiro Samo Gudo Eliane Carmo , Conceição da Cunha Amélia , Manuel Rolanda Carmen , Catorze Maria Goreti , Del Pillar Montero Maria , Luciano Gilda da Graça
Published: December 2017

A infecção por citomegalovírus tem distribuição mundial com alta prevalência nos países subdesenvolvidos, onde atinge quase 100% da população. As manifestações cutâneas são raras. A apresentação inespecífica das mesmas pode contribuir para o subdiagnóstico da doença. Relatamos o caso clínico de uma doente de 24 anos, gravemente imunodeprimida, com ulcerações na pele com quatro meses de evolução, e diagnóstico de infecção por vírus de imunodeficiência humana tipo 1 dois meses após o início das lesões. Na terceira semana de internamento desenvolveu uma retinite aguda por citomegalovírus e, embora tenha iniciado tratamento antirretrovírico e depois ganciclovir acabou por falecer após três meses por pericardite aguda.
PSEUDOXANTOMA ELÁSTICO: RELATO DE CASO
Authors: BALTAZAR ISABELLA LEMOS
Published: December 2017

Pseudoxantoma elástico (PXE) é uma doença hereditária autossômica recessiva do tecido conjuntivo, rara, com defeito molecular no gene ABCC6. Esta disfunção acarreta acúmulo de cálcio nos tecidos ocasionando degenerescência das fibras elásticas, principalmente do globo ocular, do sistema cardiovascular, e da pele. Apresenta-se nesse relato o caso de um paciente de 61 anos, com PXE, com diminuição da acuidade visual há 5 anos e pápulas amareladas, assintomáticas, nas axilas e pescoço há 30 anos.
Efeitos Cutâneos da Iontoforese com Água Não Mineral no Tratamento da Hiperidrose Palmar: Relato de Caso
Authors: Mendes dos Santos Carolyne , Fabri Mazza Maísa , Jardão Neto Domingos , J. Maldonado Maria Cristina
Published: December 2017

A sudorese excessiva, isolada ou associada, caracteriza a hiperidrose, que comumente ocorre na fronte, mãos, pés e axilas. Atinge cerca de 1% da população geral acometendo homens e mulheres de todas as idades. Apesar de sua função termorregulatória indispensável, o suor excessivo causa impacto significativo na qualidade de vida pessoal e profissional dos pacientes. É uma doença benigna, de diagnóstico essencialmente clínico, onde o tratamento pode ser conservador ou cirúrgico. Descrevemos o caso de uma paciente mulher, 27 anos, que apresentava hiperidrose palmar desde início da adolescência e que após diversos insucessos e dificuldades terapêuticas, obteve excelente resposta clínica à iontoforese com água não mineral. A paciente estava há pelo menos um ano sem tratamento clínico.
a)	Influência do índice de massa corporal e da dieta na fisiopatologia da Acne Vulgaris
Authors: Silva José Pedro Oliveira Pinheiro da , Velho Glória Maria Cardoso da Cunha
Published: December 2017

Acne vulgaris é uma das patologias dermatológicas mais comuns na população geral, principalmente em adolescentes e jovens adultos. Esta patologia afeta os folículos pilossebáceos através de processos de hiperqueratose, hipersecreção sebácea, colonização microbiana (Propionibacterium acnes e Malassezia furfur) e mecanismos imunológicos e pode ser descrita tanto como inflamatória (pápulas, pústulas ou nódulos) ou não inflamatória (comedões abertos ou fechados). Apesar de não existir mortalidade associada, existe normalmente significativa morbilidade física e psicológica, como cicatrizes permanentes, baixa autoestima, depressão e ansiedade. A fisiopatologia desta doença é multifatorial, sendo que vários estudos provam a importância de vários fatores genéticos e não genéticos, como diversos mecanismos reguladores endócrinos e a dieta, no aparecimento da acne. Estudos associam a dieta ocidental (carbohidratos hiperglicémicos, leite e lacticínios e gorduras saturadas) e o índice de massa corporal excessivo (excesso de peso e obesidade) ao aparecimento de Acne Vulgaris, sendo que existe evidência do papel da hiperinsulinémia e da resistência à insulina nesta associação. Será assim avaliada nesta dissertação a atual literatura que aborda a fisiopatologia da Acne Vulgaris, com especial foco na relação entre os reguladores endócrinos (androgénios e insulin-like growth factor 1) e reguladores celulares (Forkhead box protein 01, kinase proteica Akt) e os diferentes alimentos da dieta, dando relevância às peculiaridades da dieta ocidental e do seu papel no aparecimento de acne nas diferentes pool´s genéticas mundiais. Será também explorada a relação entre o índice de massa corporal e o aparecimento de acne, bem como a importância das adipocinas na etiologia da acne. O objetivo deste trabalho é contribuir para o melhor conhecimento da fisiopatologia desta interessante e frequente patologia. Sendo uma área muito estudada, torna-se fulcral a existência de artigos de revisão, que compilem, sintetizem e ao mesmo tempo analisem criticamente a literatura científica existente.
Carcinoma Avançado de Células de Merkel: Um Novo Caso de Regressão Espontânea
Authors: Guiote Victoria , Cunha Fernanda , Pinho André , Brinca Ana , Vieira Ricardo
Published: December 2017

O carcinoma de células de Merkel é uma neoplasia cutânea agressiva que afecta predominantemente indivíduos idosos ou imunodeprimidos. A progressão para doença metastática é frequente, enquanto a regressão espontãnea é bastante rara. A exposição crónica à radiação solar e a infecção pelo poliomavírus das células de Merkel são reconhecidos factores etiopatogénicos. Uma mulher de 89 anos foi observada com um carcinoma de células de Merkel localmente avançado na asa esquerda do nariz. Tinha doença ganglionar metastática na região submandibular clinicamente evidente, confirmada por punção aspirativa com agulha fina. Uma metástase hepatica isolada foi detectada por estudo tomográfico por emissão de positrões com (68)Ga-DOTATOC. Enquanto aguardava por radioterapia paliativa, observou-se regressão do tumor primário e das metástases ganglionares, clinicamente completa ao fim de 6 semanas. Uma ecografia hepática demonstrou regressão concomitante da metástase hepatica. Os relatos de regressão espontânea de carcinoma de Merkel são muito escassos na literatura. Após a revisão realizada pelos autores, este é o primeiro caso descrito em Portugal. O mecanismo subjacente à remissão espontânea é desconhecido, embora possa ser teioricamente explicado pelo desenvolvimento de uma resposta immune eficaz contra o tumor.
Online Identification of Photovoltaic Source Parameters by Using a Genetic Algorithm
Authors: Petrone Giovanni , Luna Massimiliano , La Tona Giuseppe , Di Piazza Maria , Spagnuolo Giovanni
Published: December 2017

In this paper, an efficient method for the online identification of the photovoltaic single-diode model parameters is proposed. The combination of a genetic algorithm with explicit equations allows obtaining precise results without the direct measurement of short circuit current and open circuit voltage that is typically used in offline identification methods. Since the proposed method requires only voltage and current values close to the maximum power point, it can be easily integrated into any photovoltaic system, and it operates online without compromising the power production. The proposed approach has been implemented and tested on an embedded system, and it exhibits a good performance for monitoring/diagnosis applications.
Eliminating Light-Induced Degradation in Commercial p-Type Czochralski Silicon Solar Cells
Authors: Hallam Brett , Herguth Axel , Hamer Phillip , Nampalli Nitin , Wilking Svenja , Abbott Malcolm , Wenham Stuart , Hahn Giso
Published: December 2017

This paper discusses developments in the mitigation of light-induced degradation caused by boron-oxygen defects in boron-doped Czochralski grown silicon. Particular attention is paid to the fabrication of industrial silicon solar cells with treatments for sensitive materials using illuminated annealing. It highlights the importance and desirability of using hydrogen-containing dielectric layers and a subsequent firing process to inject hydrogen throughout the bulk of the silicon solar cell and subsequent illuminated annealing processes for the formation of the boron-oxygen defects and simultaneously manipulate the charge states of hydrogen to enable defect passivation. For the photovoltaic industry with a current capacity of approximately 100 GW peak, the mitigation of boron-oxygen related light-induced degradation is a necessity to use cost-effective B-doped silicon while benefitting from the high-efficiency potential of new solar cell concepts.
Attenuation of Temperature Fluctuations on an External Surface of the Wall by a Phase Change Material-Activated Layer
Authors: Heim Dariusz , Wieprzkowicz Anna
Published: December 2017

Periodical changes of temperature on an external surface of building envelope, e.g., thermal stress or excessive heat gains, is often an undesirable phenomenon. The idea proposed and described in the following paper is to stabilize the external surface temperature in a period of significant heat gains by the originally developed, novel composite modified by phase change material (PCM) and applied as an external, thin finishing plaster layer. The PCM composite is made from porous, granulated perlite soaked with paraffin wax (Tm = 25 °C) and macro-encapsulated by synthetic resin. The effect of temperature attenuation was estimated for two designated periods of time—the heat gains season (HGS) and the heat losses season (HLS). The attenuation coefficient (AC) was proposed as evaluation parameter of isothermal storage of heat gains determining the reduction of temperature fluctuations. The maximum registered temperature of an external surface for a standard insulation layer was around 20 K higher than for the case modified by PCM. The calculated values of AC were relatively constant during HGS and around two times lower for PCM case. The obtained results confirmed that the proposed modification of an external partition by equipped with additional PCM layer can be effectively used to minimize temperature variations and heat flux in the heat gains season.
Na-Doping Effects on Thermoelectric Properties of Cu2−xSe Nanoplates
Authors: Jin Yingshi , Han Mi-Kyung , Kim Sung-Jin
Published: December 2017

For this work, a β-phase Cu2−xSe nanowire and nanoplate, and a Na-doped Cu2−xSe nanoplate were successfully synthesized using solution syntheses. The morphologies of the Cu2−xSe nanowire and nanoplate could be easily controlled by changing the synthetic condition. The Na-doped Cu2−xSe nanoplate was prepared by a simple treatment of the Cu2−xSe nanoplate with a sodium hydroxide-ethylene glycol solution. The nanopowders were then consolidated to bulk materials using spark plasma sintering (SPS). The phase structure and the microstructure of all of the samples were checked using X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), and scanning electron microscope (SEM) analyses. The thermoelectric transport properties, such as the electrical conductivity, Seebeck coefficient, carrier concentration, carrier mobility, and thermal conductivity, were measured at temperature ranges from 323 to 673 K. The results show that Na played two important roles: one is reducing the carrier concentration, thereby improving the Seebeck coefficient, the other is reducing the thermal conductivity. Overall, the maximum thermoelectric figure of merit (ZT) of 0.24 was achieved at 673 K in the Na-doped Cu2−xSe nanoplate.
Feeding Intolerance in Children with Severe Impairment of the Central Nervous System: Strategies for Treatment and Prevention
Authors: Hauer Julie
Published: December 2017

Children with severe impairment of the central nervous system (CNS) experience gastrointestinal (GI) symptoms at a high rate and severity, including retching, vomiting, GI tract pain, and feeding intolerance. Commonly recognized sources of symptoms include constipation and gastroesophageal reflux disease. There is growing awareness of sources due to the impaired nervous system, including visceral hyperalgesia due to sensitization of sensory neurons in the enteric nervous system and central neuropathic pain due to alterations in the thalamus. Challenging the management of these symptoms is the lack of tests to confirm alterations in the nervous system as a cause of symptom generation, requiring empirical trials directed at such sources. It is also common to have multiple reasons for the observed symptoms, further challenging management. Recurrent emesis and GI tract pain can often be improved, though in some not completely eliminated. In some, this can progress to intractable feeding intolerance. This comprehensive review provides an evidence-based approach to care, a framework for recurrent symptoms, and language strategies when symptoms remain intractable to available interventions. This summary is intended to balance optimal management with a sensitive palliative care approach to persistent GI symptoms in children with severe impairment of the CNS.
Atomic Characterization of Byproduct Nanoparticles on Cesium Lead Halide Nanocrystals Using High-Resolution Scanning Transmission Electron Microscopy
Authors: Zhang Mian , Li Hongbo , Jing Qiang , Lu Zhenda , Wang Peng
Published: December 2017

Recent microstructural studies on lead halide perovskite nanocrystals have consistently reported the coexistence of byproduct nanoparticles (NPs). However, the nature of these NPs and their formation mechanism are still a matter of debate. Herein, we have investigated the structure and compositions of the NPs located on colloidal cesium lead bromide nanocrystals (CsPbBr3 NCs), mainly through aberration-corrected transmission electron microscopy and spectroscopy. Our results show that these NPs can be assigned to PbBr2 and CsPb2Br5. The new CsPb2Br5 species are formed by reacting CsPbBr3 NCs with the remaining PbBr2 during the drying process. In addition, observation of the metallic Pb NPs are ascribed to the electron damage effect on CsPbBr3 NCs during transmission electron microscopy imaging.
Site- and Species-Specific Influences on Sub-Alpine Conifer Growth in Mt. Rainier National Park, USA
Authors: Legendre-Fixx Myesa , Anderegg Leander , Ettinger Ailene , HilleRisLambers Janneke
Published: December 2017

Identifying the factors that influence the climate sensitivity of treeline species is critical to understanding carbon sequestration, forest dynamics, and conservation in high elevation forest/meadow ecotones. Using tree cores from four sub-alpine conifer species collected from three sides of Mt. Rainier, WA, USA, we investigated the influences of species identity and sites with different local climates on radial growth–climate relationships. We created chronologies for each species at each site, determined influential plant-relevant annual and seasonal climatic variables influencing growth, and investigated how the strength of climate sensitivity varied across species and location. Overall, similar climate variables constrained growth on all three sides of the mountain for each of the four study species. Summer warmth positively influenced radial growth, whereas snow, spring warmth, previous summer warmth, and spring humidity negatively influenced growth. We discovered only a few subtle differences in the climate sensitivity of co-occurring species at the same site and between the same species at different sites in pairwise comparisons. A model including species by climate interactions provided the best balance between parsimony and fit, but did not lead to substantially greater predictive power relative to a model without site or species interactions. Our results imply that at treeline in moist temperate regions like Mt. Rainier, the same climatic variables drive annual variation in growth across species and locations, despite species differences in physiology and site differences in mean climates.
Projecting the Range Shifts in Climatically Suitable Habitat for Chinese Sea Buckthorn under Climate Change Scenarios
Authors: Huang Jinghua , Li Guoqing , Li Jie , Zhang Xiaoqin , Yan Meijie , Du Sheng
Published: December 2017

Understanding the impact of climate change on range shifts in climatically suitable habitats of tree species is important for national afforestation planning, which can enhance the adaptation of tree plantation to climate change through movement of tree to follow suitable climatic conditions. Here, we overlap the current and future climate-related ranges of Chinese sea buckthorn (Hippophae rhamnoides subsp. sinensis), an important tree used for afforestation in China, to estimate the range shift in three geographic dimensions (latitude, longitude and elevation) between 2000 and 2070, which are projected by the maximum entropy algorithm (MaxEnt) under current climate conditions and four climate change scenarios (RCP2.6, RCP4.5, RCP6.0, and RCP8.5). Our results show that the performance of the MaxEnt is highly accurate, with test AUC (area under the receiver operating characteristic curve) value of 0.91, Kappa value of 0.83 and predicted accuracy of 92%. About 10.7% area of land in China is climatically suitable for Chinese sea buckthorn plantation. Low representative concentration paths will have more effect on loss of climatic range and less effect on expansion of climatic range for Chinese sea buckthorn, while the impacts of high representative concentration path is the opposite. The centroids of climatic ranges will shift westward or northwestward at the rate of 10.4–22 km per decade, and the centroids of altitude will shift upward at the rate of 43–128 m per decade. The expansion area of climatically suitable habitat, covering 2.6–5.2 × 105 km2, is expected to be mainly located in parts of Qinghai, Ningxia, Gansu, Sichuan, Liaoning, and Jilin provinces; these areas should be monitored for planting of Chinese sea buckthorn in the future.
Differential Preference of Burkholderia and Mesorhizobium to pH and Soil Types in the Core Cape Subregion, South Africa
Authors: Dludlu Meshack , Chimphango Samson , Stirton Charles , Muasya A.
Published: December 2017

Over 760 legume species occur in the ecologically-heterogeneous Core Cape Subregion (CCR) of South Africa. This study tested whether the main symbionts of CCR legumes (Burkholderia and Mesorhizobium) are phylogenetically structured by altitude, pH and soil types. Rhizobial strains were isolated from field nodules of diverse CCR legumes and sequenced for 16S ribosomic RNA (rRNA), recombinase A (recA) and N-acyltransferase (nodA). Phylogenetic analyses were performed using Bayesian and maximum likelihood techniques. Phylogenetic signals were determined using the D statistic for soil types and Pagel’s λ for altitude and pH. Phylogenetic relationships between symbionts of the narrowly-distributed Indigofera superba and those of some widespread CCR legumes were also determined. Results showed that Burkholderia is restricted to acidic soils, while Mesorhizobium occurs in both acidic and alkaline soils. Both genera showed significant phylogenetic clustering for pH and most soil types, but not for altitude. Therefore, pH and soil types influence the distribution of Burkholderia and Mesorhizobium in the CCR. All strains of Indigofera superba were identified as Burkholderia, and they were nested within various clades containing strains from outside its distribution range. It is, therefore, hypothesized that I. superba does not exhibit rhizobial specificity at the intragenic level. Implications for CCR legume distributions are discussed.
Physiological and Pathological Roles of CaMKII-PP1 Signaling in the Brain
Authors: Shioda Norifumi , Fukunaga Kohji
Published: December 2017

Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII), a multifunctional serine (Ser)/threonine (Thr) protein kinase, regulates diverse activities related to Ca2+-mediated neuronal plasticity in the brain, including synaptic activity and gene expression. Among its regulators, protein phosphatase-1 (PP1), a Ser/Thr phosphatase, appears to be critical in controlling CaMKII-dependent neuronal signaling. In postsynaptic densities (PSDs), CaMKII is required for hippocampal long-term potentiation (LTP), a cellular process correlated with learning and memory. In response to Ca2+ elevation during hippocampal LTP induction, CaMKIIα, an isoform that translocates from the cytosol to PSDs, is activated through autophosphorylation at Thr286, generating autonomous kinase activity and a prolonged Ca2+/CaM-bound state. Moreover, PP1 inhibition enhances Thr286 autophosphorylation of CaMKIIα during LTP induction. By contrast, CaMKII nuclear import is regulated by Ser332 phosphorylation state. CaMKIIδ3, a nuclear isoform, is dephosphorylated at Ser332 by PP1, promoting its nuclear translocation, where it regulates transcription. In this review, we summarize physio-pathological roles of CaMKII/PP1 signaling in neurons. CaMKII and PP1 crosstalk and regulation of gene expression is important for neuronal plasticity as well as survival and/or differentiation.
Hepatitis C Virus: Viral Quasispecies and Genotypes
Authors: Tsukiyama-Kohara Kyoko , Kohara Michinori
Published: December 2017

Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance.
Descriptor Selection via Log-Sum Regularization for the Biological Activities of Chemical Structure
Authors: Xia Liang-Yong , Wang Yu-Wei , Meng De-Yu , Yao Xiao-Jun , Chai Hua , Liang Yong
Published: December 2017

The quantitative structure-activity relationship (QSAR) model searches for a reliable relationship between the chemical structure and biological activities in the field of drug design and discovery. (1) Background: In the study of QSAR, the chemical structures of compounds are encoded by a substantial number of descriptors. Some redundant, noisy and irrelevant descriptors result in a side-effect for the QSAR model. Meanwhile, too many descriptors can result in overfitting or low correlation between chemical structure and biological bioactivity. (2) Methods: We use novel log-sum regularization to select quite a few descriptors that are relevant to biological activities. In addition, a coordinate descent algorithm, which uses novel univariate log-sum thresholding for updating the estimated coefficients, has been developed for the QSAR model. (3) Results: Experimental results on artificial and four QSAR datasets demonstrate that our proposed log-sum method has good performance among state-of-the-art methods. (4) Conclusions: Our proposed multiple linear regression with log-sum penalty is an effective technique for both descriptor selection and prediction of biological activity.
NewSTEPs: The Establishment of a National Newborn Screening Technical Assistance Resource Center
Authors: Ojodu Jelili , Singh Sikha , Kellar-Guenther Yvonne , Yusuf Careema , Jones Elizabeth , Wood Thalia , Baker Mei , Sontag Marci
Published: December 2017

As newborn screening (NBS) programs in the US implement expanded screening panels, utilize emerging technologies and identify areas for improvement, the need to establish and maintain a community engagement based national technical assistance center becomes apparent. The Newborn Screening Technical assistance and Evaluation Program (NewSTEPs)—a program of the Association of Public Health Laboratories (APHL) in partnership with the Colorado School of Public Health (ColoradoSPH), offers expertise in newborn screening program development, member connection, data analysis, and program evaluation. NewSTEPs provides a secure online data repository designed to collect comprehensive data on newborn screening programs in three strata: state profiles (description of each state program including program hours, fees, and disorders screened), quality indicators (metrics of program performance encompassing screening accuracy and timeliness) and NBS public health surveillance case definitions. NewSTEPs was created in 2012 under a cooperative agreement with the United States Department of Health and Human Services (HHS), Health Resources and Services Administration (HRSA), Maternal and Child Health Bureau (MCHB). Successful activities of NewSTEPs have resulted in the establishment of a technical assistance resource center and the organization of a network of newborn screening experts. In addition, NewSTEPs coordinates efforts with other federally funded programs in order to maximize resources and to ensure a unified approach to data collection and information sharing.
Epithelial Mesenchymal Transition in Embryonic Development, Tissue Repair and Cancer: A Comprehensive Overview
Authors: Kim Do , Xing Tiaosi , Yang Zhibin , Dudek Ronald , Lu Qun , Chen Yan-Hua
Published: December 2017

The epithelial mesenchymal transition (EMT) plays a central role in both normal physiological events (e.g., embryonic development) and abnormal pathological events (e.g., tumor formation and metastasis). The processes that occur in embryonic development are often reactivated under pathological conditions such as oncogenesis. Therefore, defining the regulatory networks (both gene and protein levels) involved in the EMT during embryonic development will be fundamental in understanding the regulatory networks involved in tumor development, as well as metastasis. There are many molecules, factors, mediators and signaling pathways that are involved in the EMT process. Although the EMT is a very old topic with numerous publications, recent new technologies and discoveries give this research area some new perspective and direction. It is now clear that these important processes are controlled by a network of transcriptional and translational regulators in addition to post-transcriptional and post-translational modifications that amplify the initial signals. In this review article, we will discuss some key concepts, historical findings, as well as some recent progresses in the EMT research field.
Organic Thin Film Transistors Incorporating Solution Processable Thieno[3,2-b]thiophene Thienoacenes
Authors: Rice Nicole , Magnan François , Melville Owen , Brusso Jaclyn , Lessard Benoît
Published: December 2017

Bottom-gate bottom-contact organic thin film transistors (OTFTs) were prepared with four novel star-shaped conjugated molecules containing a fused thieno[3,2-b]thiophene moiety incorporated either in the core and/or at the periphery of the molecular framework. The molecules were soluble in CS2, allowing for solution-processing techniques to be employed. OTFTs with different channel geometries were characterized in both air and vacuum in order to compare environmental effects on performance. Blending the small molecules with poly(styrene), an insulating polymer, facilitated the formation of an even semiconducting film, resulting in an order of magnitude increase in device mobility. The highest field-effect mobilities were in air and on the order of 10−3 cm2/Vs for three of the four molecules, with a maximum mobility of 9.2 × 10−3 cm2/Vs achieved for the most conjugated small molecule. This study explores the relationship between processing conditions and OTFT devices performance for four different molecules within this new family of materials, resulting in a deeper insight into their potential as solution-processable semiconductors.
Characterization of Early Age Curing and Shrinkage of Metakaolin-Based Inorganic Binders with Different Rheological Behavior by Fiber Bragg Grating Sensors
Authors: Palumbo Giovanna , Iadicicco Agostino , Messina Francesco , Ferone Claudio , Campopiano Stefania , Cioffi Raffaele , Colangelo Francesco
Published: December 2017

This paper reports results related to early age temperature and shrinkage measurements by means fiber Bragg gratings (FBGs), which were embedded in geopolymer matrices. The sensors were properly packaged in order to discriminate between different shrinkage behavior and temperature development. Geopolymer systems based on metakaolin were investigated, which dealt with different commercial aluminosilicate precursors and siliceous filler contents. The proposed measuring system will allow us to control, in a very accurate way, the early age phases of the binding systems made by metakaolin geopolymer. A series of experiments were conducted on different compositions; moreover, rheological issues related to the proposed experimental method were also assessed.
Extraction of the Anisotropic Plasticity of Metal Materials by Using Inverse Analysis and Dual Indentation Tests
Authors: Wang Mingzhi , Wu Jianjun , Fan He , Zhang Zengkun , Wu Hongfei
Published: December 2017

In this paper, a novel inverse computation approach is proposed to extract the anisotropic plasticity parameters of metal materials by using inverse analysis and dual indentation tests. Based on dimensional analysis and extensive finite element (FE) simulations, four independent dimensionless functions are derived to correlate the anisotropic plasticity parameters with material responses in dual indentation tests. Besides, an inverse calculation algorithm is suggested, to estimate the unknown anisotropic parameters of the indented specimens using the information collected from indentation. The proposed numerical approach is applied on a series of engineering materials. Results show that the inverse analysis is ill-posed when only the load-displacement (P-h) curves in dual indentation tests were used. This problem can be effectively alleviated by introducing the pile-up effect as the additional information. The new method is proved to be very effective and reliable.
Microstructure Evolution and Microstructural Characteristics of Al–Mg–Si Aluminum Alloys Fabricated by a Modified Strain-Induced Melting Activation Process
Authors: Lin Chia-Wei , Hung Fei-Yi , Lui Truan-Sheng
Published: December 2017

A modified strain-induced melting activation (SIMA) process is shown to improve high-temperature formability. The microstructural characteristics of the spheroidized grains of SIMA-processed alloys affect high-temperature formability. The effects of hot extrusion parameters and chemical composition on the evolution of spheroidized grains were investigated using several 6xxx series aluminum alloys subjected to a modified SIMA process. The results show that 6066 aluminum alloy is the most suitable alloy for the SIMA process, as it contains sufficient Mg, Si, Cu, and Mn. Adequate amounts of Mg, Si, and Cu lead to a high liquid fraction, and a sufficient addition of Mn inhibits grain growth. Proper hot extrusion parameters are essential, because initial fine and uniform recrystallized grains lead to fine and uniform globules. The phases at the global grain boundaries of 6066 aluminum alloy are eutectic phases of Al and Si, Al and Mg2Si, and Al and Al2Cu, as analyzed using transmission electron microscopy.
Arginylglycylaspartic Acid-Surface-Functionalized Doxorubicin-Loaded Lipid-Core Nanocapsules as a Strategy to Target Alpha(V) Beta(3) Integrin Expressed on Tumor Cells
Authors: Antonow Michelli , Franco Camila , Prado Willian , Beckenkamp Aline , Silveira Gustavo , Buffon Andréia , Guterres Sílvia , Pohlmann Adriana
Published: December 2017

Doxorubicin (Dox) clinical use is limited by dose-related cardiomyopathy, becoming more prevalent with increasing cumulative doses. Previously, we developed Dox-loaded lipid-core nanocapsules (Dox-LNC) and, in this study, we hypothesized that self-assembling and interfacial reactions could be used to obtain arginylglycylaspartic acid (RGD)-surface-functionalized-Dox-LNC, which could target tumoral cells overexpressing αvβ3 integrin. Human breast adenocarcinoma cell line (MCF-7) and human glioblastoma astrocytoma (U87MG) expressing different levels of αvβ3 integrin were studied. RGD-functionalized Dox-LNC were prepared with Dox at 100 and 500 mg·mL−1 (RGD-MCMN (Dox100) and RGD-MCMN (Dox500)). Blank formulation (RGD-MCMN) had z-average diameter of 162 ± 6 nm, polydispersity index of 0.11 ± 0.04, zeta potential of +13.2 ± 1.9 mV and (6.2 ± 1.1) × 1011 particles mL−1, while RGD-MCMN (Dox100) and RGD-MCMN (Dox500) showed respectively 146 ± 20 and 215 ± 25 nm, 0.10 ± 0.01 and 0.09 ± 0.03, +13.8 ± 2.3 and +16.4 ± 1.5 mV and (6.9 ± 0.6) × 1011 and (6.1 ± 1.0) × 1011 particles mL−1. RGD complexation was 7.73 × 104 molecules per nanocapsule and Dox loading were 1.51 × 104 and 7.64 × 104 molecules per nanocapsule, respectively. RGD-functionalized nanocapsules had an improved uptake capacity by U87MG cells. Pareto chart showed that the cell viability was mainly affected by the Dox concentration and the period of treatment in both MCF-7 and U87MG. The influence of RGD-functionalization on cell viability was a determinant factor exclusively to U87MG.
Modeling of Structure Effect for Ferroelectric Capacitor Based on Poly(vinylidene fluoride-trifluoroethylene) Ultrathin Films
Authors: Li Long , Zhang Xiuli , Chen Hongzhen , Sun Xiaohui , Yuan Haidong , Xu Haisheng
Published: December 2017

The characteristics of ferroelectric capacitors with poly(vinylidene fluoride-trifluoroethlene) (P(VDF-TrFE)) films have been studied at different structures of cell electrodes. It is suggested that the effect of electrode structures could induce changes of performance. Remarkably, cells with line electrodes display a better polarization and fatigue resistance than those with flat electrodes. For P(VDF-TrFE) ultrathin films with different electrode structures, the models of charge compensation mechanism for depolarization field and domain fatigue decomposition are used to explain the effect of electrode structure. Furthermore, the driving voltage based on normal speed-functionality is designed, and the testing results show that the line electrode structure could induce a robust switching, which is determined by the free charges concentration in active layer. These findings provide an effective route to design the optimum structure for a ferroelectric capacitor based on P(VDF-TrFE) copolymer ultrathin film.
Spectroscopic Techniques for the Characterization of Polymer Nanocomposites: A Review
Authors: Bokobza Liliane
Published: December 2017

Due to the growing interest in nanocomposites, a molecular characterization of these materials is essential for the understanding of their properties and for the development of new materials. Spectroscopic techniques that bring information at a molecular level are unavoidable when characterizing polymers, fillers and composites. Selected examples of the application of fluorescence, solid-state nuclear magnetic resonance (NMR), infrared and Raman spectroscopies, illustrate the potential of these techniques for the analysis of the filler surface, the evaluation of the state of filler dispersion in the host matrix, the extent of interaction between the polymer and the filler particles or the dynamics of polymer chains at the polymer–filler interface.