bluuebunny/crossref_metadata_2025 huggingface dataset:
Can the Stockholm convention address the spectrum of chemicals currently under regulatory scrutiny? Advocating a more prominent role for modeling in POP screening assessment
Authors: McLachlan Michael S.
Published: January 2018

Applying POP screening to a large chemical domain requires less reliance on individual criteria and more on integrated assessment with models.
Exploring the potential of newly synthesized 4-methyl-6-morpholino-pyrimidine derivatives as antiproliferative agents
Authors: Gaonkar Supreet , Savanur Mohammed Azharuddin , Sunagar Manjunath G. , Puthusseri Bijesh , Deshapande Narahari , Nadaf Afra A. , Khazi Imtiyaz Ahmed M.
Published: January 2018

A series of 4-methyl-6-morpholinopyrimidine derivatives were synthesised and found to prevent cancer cell proliferation by inducing apoptosis.
Silver(i) complexes with 2-acetylpyridinebenzoylhydrazones exhibit antimicrobial effects against yeast and filamentous fungi
Authors: Santos Ane F. , Ferreira Isabella P. , Takahashi Jacqueline A. , Rodrigues Gabriel L. S. , Pinheiro Carlos B. , Teixeira Letícia R. , Rocha Willian R. , Beraldo Heloisa
Published: January 2018

2-Acetylpyridinebenzoylhydrazones and their silver(i) complexes show antimicrobial effects and deserve to be investigated as antifungal drug candidates.
DBU-promoted carbonylative synthesis of 1,3-oxathiolan-2-ones from propargylic alcohols with TFBen as the CO source
Authors: Ying Jun , Zhou Chao , Wu Xiao-Feng
Published: January 2018

A DBU-promoted carbonylative cyclization of propargylic alcohols with sulfur was developed.
Ion-selective asymmetric carbon electrodes for enhanced capacitive deionization
Authors: Yan Tingting , Xu Baoxia , Zhang Jianping , Shi Liyi , Zhang Dengsong
Published: January 2018

Ion-selective asymmetric carbon electrodes are developed for capacitive deionization to minimize the co-ion effects.
Metastable ferroelectric phase and crossover in the Ba2NdFeNb4−xTaxO15TTB solid solution
Authors: Albino M. , Heijboer P. , Porcher F. , Decourt R. , Veber P. , Maglione M. , Josse M.
Published: January 2018

Insightful chemical, structural and dielectric characterizations reveal a metastable ferroelectric phase and crossover in Ba2NdFeNb4−xTaxO15TTB.
Adipose depot-specific effects of ileal interposition surgery in UCD-T2D rats: unexpected implications for obesity and diabetes
Authors: Hung Connie , Bronec Casey , Napoli Eleonora , Graham James , Stanhope Kimber L. , Marsilio Ilaria , Giron Maria Cecilia , Havel Peter J. , Giulivi Cecilia
Published: January 2018

Ileal interposition (IT) surgery delays the onset of diabetes in a rat model of type-2 diabetes (UCD-T2DM). Here, to gain a deeper understanding of the molecular events underlying the effects of IT surgery, we examined the changes in the proteome of four white adipose depots (retroperitoneal, mesenteric, inguinal, and epididymal) and plasma-free fatty acid profile in pre-diabetic rats 1.5 months following IT or sham surgery. The IT-mediated changes were exerted mainly in mesenteric fat and spanned from delayed adipocyte maturation to a neuroendocrine remodeling. Conversely, inguinal, retroperitoneal, and epididymal depots showed opposite trends consistent with increased adipocyte maturation and adipogenesis development prior to overt signs of diabetes, probably orchestrated by peroxisome proliferator-activated receptor gamma signaling and higher plasma n-6/n-3 free fatty acid ratios. The resulting scenario suggests a targeted use of surgical strategies that seek to delay or improve diabetes in order to manipulate adipose depot-specific responses to maximize the duration and beneficial effects of the surgery.
Harmonic analysis of jitter in an ultra‐stable fibre laser regeneratively mode‐locked at 10 GHz
Authors: Ng W. , Stasyuk V.
Published: January 2018

An evaluation of the amplitude jitter and timing jitter for a regeneratively mode‐locked fibre laser via the use of the harmonic analysis approach is presented. The RF power spectrum of four harmonics derived from a 10 GHz mode‐locked pulse train was measured with high resolution. From a detailed analysis of the noise pedestal present in these harmonics, an amplitude jitter of ∼0.3% and an absolute timing jitter of ∼41 fs are obtained.
Influence of moisture on the interface charge of oil–pressboard composite insulation under DC voltage
Authors: Qi Bo , Jiao Yanqiu , Gao Chunjia , Zhang Shuqi , Zhao Xiaolin , Li Chengrong
Published: January 2018

The distortion of the electric field in the oil–pressboard composite insulation caused by the accumulation of the interface charge is detrimental to both the insulation design and operation of converter transformers. The influence of moisture content on the surface charge accumulation of oil–pressboard insulation under DC voltage was studied in this study. In accordance with the Kerr electro‐optic effect, the electric field strengths in transformer oil and the surface charge density were acquired after applying the positive and negative DC voltages in three oil–pressboard insulation models with different moisture content, respectively. The resistivities of the oil and pressboard in three models, namely Model 1# with 3.8–4.2 ppm moisture in oil and 0.35–0.37% moisture in pressboard, Model 2# with 7.6–7.9 ppm moisture in oil and 0.79–0.82% moisture in pressboard and Model 3# with 14.9–15.4 ppm moisture in oil and 1.39–1.42% moisture in pressboard, was also measured. The results indicate that: (i) as negative charges in oil accumulated on the pressboard surface in a much greater speed than the positive ones, the electric field in transformer oil under negative DC voltage decreases more rapidly with time than that under positive DC voltage; (ii) the increase of the moisture content in both oil and pressboard, under either positive or negative DC voltage, leads to the decrease of both the electric field strength in transformer oil and the charge density with time; and (iii) the increase of moisture content could not only decrease the resistivity of both oil and pressboard, but also the ratio of the resistivity between the pressboard and the oil. On the basis of the Maxwell–Wagner theory, the decrease of the ratio between the pressboard and oil could lead to the decrease of the interfacial charge density, leading to the slow transient process of the electric field in transformer oil under DC voltage.
Distributed optimal residential demand response considering operational constraints of unbalanced distribution networks
Authors: Zheng Weiye , Wu Wenchuan , Zhang Boming , Lin Chenhui
Published: January 2018

As a typical approach to demand response (DR), direct load control (DLC) enables a load service entity (LSE) to adjust the electricity usage of residential customers for peak shaving during a DLC event. Households are connected in low‐voltage distribution networks, which are always three‐phase unbalanced. However, existing work has not considered the detailed operational constraints of three‐phase distribution networks, which may lead to decisions that deviate from reality or are even infeasible in practice. Moreover, centralised control may cause privacy and communication issues. This study proposes a distributed residential DLC method that considers the operational constraints of three‐phase unbalanced distribution networks and privacy of residential customers. Numerical tests on IEEE benchmark systems demonstrate effectiveness of the method. The proposed distributed method can converge within 17 iterations in IEEE 123‐bus distribution system, which demonstrates scalability of the proposed algorithm.
Detection of PMU spoofing in power grid based on phasor measurement analysis
Authors: Yasinzadeh Mohammad , Akhbari Mahdi
Published: January 2018

In some recent articles, the vulnerability of phasor measurement unit (PMU) to the time synchronisation attack by spoofing its global positioning system (GPS) has been highlighted as a threat to power grid protection, control and monitoring system. Having spoofed PMU GPS signals, one can manipulate the measurements and inject bad data to power grid protection and monitoring system. The existing anti‐spoofing methods are all based on GPS signal analysis. The mentioned methods are just able to detect spoofing without any data refinement as the data of power grid has not been practically used in calculations. Furthermore, some of these methods lose their certainty in noisy and harsh environments due to low power of GPS signals. A novel anti‐spoofing algorithm has been proposed based on power grid infrastructures which can join to any of the existing anti‐spoofing algorithm to empower spoofing detection process. The proposed algorithm adopts phasor measurement analysis and state estimation methods to detect spoofing. The composite of this algorithm with any of the existing algorithms will not only cover the probable malfunctioning in spoofing detection but also be able to refine counterfeit measurements.
Police‐less multi‐party traffic violation detection and reporting system with privacy preservation
Authors: Özkul Mükremin , Çapuni Ilir
Published: January 2018

This study presents a traffic violation detection and reporting system, that does not rely on costly infrastructure or the presence of law enforcement. It relies solely on broadcast messages among vehicles and reports delivery to the transportation authority. A vehicle is modelled as an automaton (in the computational sense) that has its own state and has a read access to the state of other automata of other vehicles in a constant size neighbourhood. The common traffic rules and communication rules make the program of these automata that guide the transitions of the vehicles in space and time. By observing the transitions of the vehicles in their neighbourhood, a vehicle can decide if these comply with the traffic rules encoded in the system. Whenever a transition is not performed according to the program, a violation occurs. These violations are reported and witnessed to the transportation authority by the vehicles in the neighbourhood, which act as witnesses and reporters. The system preserves privacy and allows no false positives.
Characteristics of GeSn‐based multiple quantum well heterojunction phototransistors: a simulation‐based analysis
Authors: Pandey Ankit Kumar , Basu Rikmantra
Published: January 2018

Introduction of multiple quantum wells (MQWs) is an efficient way to enhance the light absorption capability in phototransistors. Direct band gap Ge1− x Snx alloy (x  > 0.08) having large absorption coefficient is an attractive material for heterojunction phototransistors (HPTs) compatible with CMOS platform. In this work, simulations are employed to obtain current gain, responsivity and collector current characteristics of Ge/GeSn/Ge HPTs with incorporation of MQWs (Ge0.87 Sn0.13 /Ge0.83 Sn0.17) in the base region. The performances of bulk, single quantum well and MQW HPT structures are examined and compared. Best performance is shown by HPTs having MQW structure over a wide range of base emitter voltage.
Coordinated residential energy resource scheduling with vehicle‐to‐home and high photovoltaic penetrations
Authors: Luo Fengji , Ranzi Gianluca , Kong Weicong , Dong Zhao Yang , Wang Fan
Published: January 2018

Home energy management system (HEMS) provides an effective solution to assist residential users in dealing with the complexity of dynamic electricity prices. This study proposes a new HEMS in contexts of real‐time electricity tariff and high residential photovoltaic penetrations. First, the HEMS accepts user‐specified residential energy resource operation restrictions as inputs. Then, based on the forecasted solar power outputs and electricity prices, an optimal scheduling model is proposed to support the decision making of the residential energy resource (RES) operations. For the scheduling of heating, ventilating, and air conditioning system, an advanced adaptive thermal comfort model is employed to estimate the user's indoor thermal comfort degree. For the controllable appliances, the ‘user disturbance value’ metric is proposed to estimate the psychological disturbances of an appliance schedule on the user's preference. The proposed scheduling model aims to minimise the future 1 day energy costs and disturbances to the user. A new biological self‐aggregation intelligence inspired metaheuristic algorithm recently proposed by the authors (a natural aggregation algorithm) is applied to solve the model. Extensive simulations are conducted to validate the proposed method.
Modelling of PV module and its application for partial shading analysis – part II: partial shading analysis and simulation approach of large‐scale PV array
Authors: Mao Zhang , Sunan Zhong , Peng Mao , Yanlong Sun , Weiping Zhang
Published: January 2018

Most issue for a large‐scale photovoltaic (PV) array shows an average loss of ∼20–25% in power generation yield due to partial shadow. Under partially shaded conditions, a PV array gets more complex characteristics. However, it is very difficult to understand and predict them since PV module has non‐linear characteristic and it is also utterly necessary for one to extract the maximum possible power. This study presents the partial shading analysis and simulation approach to unveil the significant basic rules for estimating performances of a large‐scale PV array. By using the macro‐model and simplified parameter estimation formulas of the PV module proposed in part I, this study has made the following contributions: (i) basic and general shading patterns of PV string and array are proposed to unveil the basic rules, such as the count of maximum power points (MPP), magnitude of the global MPP, overall shape of V –I and V –P curves, and so on. (ii) The optimising configuration‐simulation model are developed for a distributed PV system designed to optimise PV array configuration under a given shaded patterns. By using a Dell compatible personal computer to run Psim programs, it takes ∼15 minims to get the V –I and V –P curves of a partially shaded PV array with 1050 commercial PV modules. Furthermore, this study attempts to provide a simulation tool to study the behaviours of a complete PV system since the Psim‐based models conveniently interface with the models of power electronic circuit.
Pebble-isolation mass: Scaling law and implications for the formation of super-Earths and gas giants
Authors: Bitsch Bertram , Morbidelli Alessandro , Johansen Anders , Lega Elena , Lambrechts Michiel , Crida Aurélien
Published: January 2018

The growth of a planetary core by pebble accretion stops at the so-called pebble isolation mass, when the core generates a pressure bump that traps drifting pebbles outside its orbit. The value of the pebble isolation mass is crucial in determining the final planet mass. If the isolation mass is very low, gas accretion is protracted and the planet remains at a few Earth masses with a mainly solid composition. For higher values of the pebble isolation mass, the planet might be able to accrete gas from the protoplanetary disc and grow into a gas giant. Previous works have determined a scaling of the pebble isolation mass with cube of the disc aspect ratio. Here, we expand on previous measurements and explore the dependency of the pebble isolation mass on all relevant parameters of the protoplanetary disc. We use 3D hydrodynamical simulations to measure the pebble isolation mass and derive a simple scaling law that captures the dependence on the local disc structure and the turbulent viscosity parameter α. We find that small pebbles, coupled to the gas, with Stokes number τf < 0.005 can drift through the partial gap at pebble isolation mass. However, as the planetary mass increases, particles must be decreasingly smaller to penetrate the pressure bump. Turbulent diffusion of particles, however, can lead to an increase of the pebble isolation mass by a factor of two, depending on the strength of the background viscosity and on the pebble size. We finally explore the implications of the new scaling law of the pebble isolation mass on the formation of planetary systems by numerically integrating the growth and migration pathways of planets in evolving protoplanetary discs. Compared to models neglecting the dependence of the pebble isolation mass on the α-viscosity, our models including this effect result in higher core masses for giant planets. These higher core masses are more similar to the core masses of the giant planets in the solar system.
Transmastoid Repair of Spontaneous Cerebrospinal Fluid Leaks
Authors: Perez Enrique , Carlton Daniel , Alfarano Matthew , Smouha Eric
Published: January 2018

Objective Determine the efficacy of using a purely transmastoid approach for the repair of spontaneous cerebrospinal fluid (CSF) leaks and further elucidate the relationship of elevated body mass index (BMI) and skull base thickness in our patient population.

Method We conducted a retrospective chart review of patients treated for spontaneous temporal bone CSF leaks at our tertiary care institution from the years 2006 to 2015. Cases were categorized as primary or secondary. We analyzed success rates, length of stay, use of lumbar drains, BMIs, and rates of meningitis. Skull base thickness was compared with BMI in each case.

Results We identified 26 primary operations for spontaneous CSF leaks and 7 secondary operations. Twenty-three of 33 repairs were performed via the transmastoid approach alone with an 87% success rate (20/23). Of the10 repairs including a middle cranial fossa (MCF) or combined MCF-transmastoid approach, 2 failed for an 80% success rate (8/10). Five transmastoid repairs underwent placement of a lumbar drain versus all 10 repairs employing an intracranial exposure. Average length of stay for those undergoing a transmastoid approach (1.7 days) was significantly shorter than for patients undergoing a MCF repair (6.3 days). Four patients presented with meningitis. Average BMI was 35.3. No correlation was established between BMI and skull base thickness (R
2 = 0.00011).

Conclusion The transmastoid approach is effective in the majority of cases and prevents the need for an intracranial operation, resulting in lower morbidity and a shorter length of stay. We believe that this is the preferred primary approach in most patients with spontaneous CSF leaks.
Discectomia percutânea a laser
Authors: Facure José Jorge
Published: January 2018

Analisamos os resultados da discetomia percutânea a laser em 27 pacientes com hérnia discal lombar. O tratamento é feito com anestesia local, em âmbito ambulatorial. Para a punção do disco, que é feita sob controle radiológico, utiliza-se uma agulha especial com mandril cuja retirada permite a introdução de uma fibra óptica de 800 μ de diâmetro, que conduzirá o laser. Para o procedimento, utilizamos o equipamento Diodo Laser Sharplan 6020. Foi aplicado, em média, um total de 1.800 joules de energia distribuído em três pontos do núcleo pulposo. Para cada ponto realizamos uma série de cinco seqüências de disparos-laser, cada série correspondendo a oito pulsos-laser de 15 watts, com duração de um segundo, atingindo-se 600 joules de energia. O período de seguimento foi de 1 a 38 meses, média de 8 meses. Os resultados foram considerados bons, com desaparecimento da dor e retorno do paciente ao mesmo trabalho anterior em 66,7% dos casos.

Concluímos que a discectomia percutânea a laser é um método efetivo que deve ser considerado como alternativa no tratamento da hérnia discal lombar.
Infarto cerebelar: Considerações sobre 12 casos
Authors: Pereira Carlos Umberto , da Silva Alvino Dutra , Duarte Diane Guimarães , Nascimento Gonçalves Ana Claudia Borges do , Andrade Tatiana Alves de , Menezes Alves Helton José Ribeiro de
Published: January 2018

Trata-se de estudo retrospectivo sobre 12 casos de infarto cerebelar. Sete pacientes eram do sexo masculino e cinco, do feminino. A idade variou entre 46 e 76 anos, com média de 54 anos. As causas foram hipertensão arterial sistêmica em seis, endocardite bacteriana em três e desconhecida em outros três. A cefaléia foi sintoma presente em dez pacientes, vômitos em oito, tonteiras em oito, ataxia da marcha em sete e vertigem em quatro. A tomografia do crânio foi útil no diagnóstico e conduta. Onze pacientes foram submetidos a tratamento conservador. Derivação ventricular externa e craniectomia suboccipital foram realizadas em um paciente. Houve quatro óbitos. O prognóstico esteve diretamente relacionado ao nível de consciência por ocasião da admissão, da extensão do infarto e da idade do paciente.
Ferida penetrante no crânio por auto-infligimento como tentativa de suicídio: Relato de caso
Authors: Santos Vieira José Francisco dos , Malaguti Carlos Roberto
Published: January 2018

Os autores relatam um caso em que o paciente, na tentativa de suicídio por auto-infligimento, penetrou um prego de 2 e ½ polegadas de comprimento no vértex do crânio, usando um martelo. Trata-se de situação não registrada na literatura pesquisada.

Apresenta-se a técnica cirúrgica empregada.
Modelos experimentais para o estudo do vasoespasmo cerebral: Revisão da literatura
Authors: de Freitas Carlos Clayton Macedo , Zanini Marco Antonio , Gabarra Roberto Colichio , Agapjev Svetlana , Abreu Maffei Francisco Humberto de
Published: January 2018

O vasoespasmo cerebral é a principal complicação da hemorragia subaracnóidea, não existindo, até o momento, um trat amento específico para ele, provavelmente em razão do desconhecimento de todos os seus mecanismos fisiopatológicos. Diante da necessidade de se conhecer melhor o vasoespasmo cerebral, vários modelos experimentais foram desenvolvidos, em diversas espécies de animais.

No presente artigo é apresentada revisão sobre os modelos experimentais de vasoespasmo cerebral, com base na pequisa no Medline Medical Database, abrangendo o período de 1960 a 2002, utilizando-se as palavras-chave “animal”, “model”, “experimental”, “vasospasm” e “hemorrhage”.

Os modelos foram classificados em três categorias, de acordo com a técnica utilizada para promover a hemorragia subaracnóidea, sendo analisadas as vantagens e desvantagens de cada categoria.
Considerações hidrodinâmicas sobre a derivação liquórica: Parte I: efeitos do cateter peritoneal
Authors: Maset Angelo L. , Castro Samuel Caputo de , Camilo José Ricardo
Published: January 2018

Este artigo é um estudo laboratorial das características do fluxo e resistência de modelos de vários tipos de cateteres peritoneais, inclusive os disponíveis comercialmente.

Utilizou-se uma bancada de testes que permitiu um controle preciso da pressão de perfusão do sistema. Os resultados demonstram que os cateteres comercialmente disponíveis não possuem resistência (Rout) significativa; o cateter aberto apresentou uma Rout que variou de 1,12 a 1,95 mmHg/ml/min, e o cateter com fendas de 10 mm apresentou uma Rout que variou de 1,22 a 1,26 mmHg/ml/min. Em humanos, os níveis considerados normais do elemento resistivo da dinâmica liquórica (Rout) é de até 3 mmHg/ml/min. Isso significa que os cateteres peritoneais testados reproduzem os valores dos elementos resistivos fisiológicos. Contudo, considerando-se a hipótese de Kajimoto, os cateteres de 8 mm e 9 mm possuem potencial para acrescentar o elemento resistivo adequado ao sistema de derivação. O cateter com fendas de 8 mm teve, em ΔPinicial de 5,15 mmHg, um fluxo de 2,11 ml/min e Rout de 2,45 mmHg/ml/min e, em ΔPsentado (14 mmHg), um fluxo de 9,96 ml/min e Rout de 1,41 mmHg/ml/min, representando um elemento resistivo adicional de 25% quando comparado ao cateter aberto tanto em ΔP inicial quanto em ΔPsentado. O cateter com fendas de 9 mm teve, em ΔPinicial de 4,05 mmHg, um fluxo de 1,93 ml/min e Rout de 2,1 mmHg/ml/min, e em ΔPsentado , um fluxo de 10,32 ml/min e Rout de 1,36 mmHg/ml/min, representando um elemento resistivo adicional de 7% em ΔPinicial e de 21% em ΔPsentado quando comparados com o cateter aberto.

Assim, os cateteres de 8 mm e 9 mm mostraram potencial para contribuir como um elemento resistivo adicional para limitar o efeito sifão, e merecerão estudos futuros para se observar os efeitos hidrodinâmicos numa bancada de testes que inclua um sistema valvular.
Fístula liquórica parietal secundária a lesão por arma branca: Relato de caso
Authors: Pereira Carlos Umberto , da Silva Alvino Dutra , Silva Santos Egmond Alves
Published: January 2018

Os autores apresentam um caso de fístula liquórica traumática provocada por arma branca, comunicando o ventrículo lateral à região parietal esquerda. O paciente foi submetido a tratamento cirúrgico para fechamento da laceração dural, evoluindo de maneira satisfatória.
Abscesso cerebral por Actinomyces odontolyticus: Relato de caso
Authors: Worm Paulo Valdeci , Faria Mário de Barros , Ferreira Marcelo Paglioli , Ferreira Nelson Pires
Published: January 2018

Actinomicose é uma infecção supurativa crônica que tende a formar abscessos. O acometimento do sistema nervoso central é evento raro, sendo crucial o diagnóstico diferencial com nocardiose para a seleção apropriada da terapia antimicrobiana. O manejo recomendado consiste na drenagem cirúrgica associada ao tratamento prolongado com antibióticos por, em média, 5 meses, além da erradicação do foco primário, quando identificado. Embora constitua uma forma tratável de abscesso cerebral, está relacionada a morbidade e mortalidade elevadas. É relatado caso de abscesso cerebral causado por Actinomyces odontolyticus em paciente imunocompetente, cuja evolução desfavorável possa estar relacionada à restrição do espectro antimicrobiano após identificação do agente etiológico.
Achatamento das fraturas tóraco-lombares em explosão após técnica de instrumentação longa e fusão curta. A instrumentação universal pode oferecer alguma vantagem?
Authors: Berthier Brasil Albert Vincent , Pereira Filho Arthur de Azambuja
Published: January 2018

Objetivo: Uma das alternativas para o tratamento cirúrgico das fraturas tóraco-lombares em explosão (TLBF) é a técnica de instrumentação longa e fusão curta (RLFS) utilizando o sistema de Harrington. A altura do corpo vertebral fraturado geralmente retorna a valores próximos do normal imediatamente após a cirurgia, mas, alguns meses depois, esse ganho é perdido (achatamento). Nosso objetivo é verificar os resultados clínicos e radiológicos com a técnica RLFS com sistema de instrumentação universal. Método: Doze casos de TLBF (masculino/feminino=9/3, média de idade=35,7 anos, Escala de Frankel: E=9, C=3) foram estudados. Através de abordagem posterior, instrumentação universal foi realizada dois níveis acima e dois níveis abaixo da vértebra fraturada. Enxerto ósseo foi colocado de um nível acima a um nível abaixo da fratura. Após pelo menos nove meses, o instrumental localizado além da área enxertada foi removido. Os resultados clínicos foram medidos pela Escala de Frankel e pelo formulário SF-36. Os parâmetros radiológicos (ângulo de Cobb, alturas anterior e posterior da vértebra fraturada) foram medidos em 3 momentos: pré-operatório, pós-operatório imediato e após a remoção do instrumental. Análise estatística foi realizada por análise de variância – ANOVA (α=0.05) e teste ̈r̈ de Pearson (p<0.05). Resultado: Não se observou piora neurológica. Todos os pacientes com lesão neurológica, exceto um deles, melhoraram um grau na escala de Frankel. Os parâmetros radiográficos melhoraram após a primeira cirurgia, mas o ganho reduziu após a remoção do material. A cifose pós-operatória interferiu negativamente na qualidade de vida dos pacientes. Conclusão: Quando a técnica RLFS é escolhida para tratar uma TLBF, o uso de instrumentação universal não mostra nenhuma vantagem sobre o sistema de Harrington em termos de resultados clínicos e radiológicos.
Fatores prognósticos da hemorragia talâmica: Considerações iniciais sobre 35 casos
Authors: Pereira Carlos Umberto , Silva Santos Egmond Alves , Silva Monteiro João Tiago
Published: January 2018

Objetivo: Estudar, prospectivamente, os fatores prognósticos de pacientes com hemorragia talâmica (HT). Métodos: Foram estudados os aspectos clínicos e tomográficos de 35 pacientes, internados no Hospital João Alves Filho, Aracaju, SE, entre agosto de 2004 e julho de 2005. Na análise estatística dos dados obtidos, foi considerado significante o valor p < 0,05. Foi utilizado teste ANOVA com pós-teste de Tukey e regressão linear. Resultados: Houve predominância do sexo feminino (63%); as idades variaram entre 46 e 84 anos com média de 64,5. A principal etiologia foi hipertensão arterial (85%) e o mais importante fator de risco vascular foi o diabetes melito (57%). O quadro clínico predominante foi cefaléia acompanhada de alterações do nível de consciência e déficit motor e sensitivo. A projeção talâmica mais acometida foi a direita (60%) e o território vascular mais envolvido foi o póstero-lateral (46%). Hematomas grandes (volume ≥ 20 cm3) foram mais freqüentes (71%). Conclusões: Na curva de regressão linear verificou-se relação significante entre o volume do hematoma e a idade do paciente. A análise estatística permitiu concluir existência de significância ao se correlacionar volume do HT e sua localização (p < 0,0001), volume do HT e quadro clínico (p < 0,0001), idade e gravidade do quadro clínico (p < 0,0001), prognóstico e volume do HT (p < 0,0001) e prognóstico e idade do paciente (p = 0,0004).
Avaliação de fatores prognósticos da deambulação em crianças com mielomeningocele
Authors: Collange Luanda André , Martins Roberto S. , Zanon-Collange Nelci , dos Santos Marco T. S. , Moraes Osmar J. S. , Franco Renata C.
Published: January 2018

Objetivo: Caracterizar o grau de acometimento neurológico, estabelecendo uma correlação entre o nível funcional da lesão e a aquisição da marcha, além de identificar os fatores que interferem nessa capacidade. Método: Foram avaliadas prospectivamente vinte e oito crianças portadoras de mielomeningocele operadas com idade igual ou superior a três anos. Foram determinados o nível funcional da lesão, a aquisição ou não da marcha e os fatores associados por meio das medidas do grau de força muscular nos membros inferiores, presença de deformidades articulares, ocorrência de contratura da musculatura flexora e trato iliotibial, eficácia da reação de equilíbrio e presença de hidrocefalia tratada. Resultados: Todos os fatores avaliados, exceto a hidrocefalia, foram relacionados de forma significativa à aquisição da marcha. Conclusão: A aquisição da marcha em crianças portadoras de mielomeningocele sofre influência de vários fatores, além do nível de acometimento neurológico, o que deve ser considerado no prognóstico e na programação terapêutica.
Das trepanações pré-históricas à neuronavegação: evolução histórica das contribuições da neuroanatomia e das técnicas de neuroimagem à prática neurocirúrgica
Authors: Ribas Guilherme Carvalhal
Published: January 2018

Em forma de revisão, o presente artigo trata do histórico das contribuições da neuroanatomia e dos métodos de neuroimagem à prática neurocirúrgica. Destaca, em particular, a evolução histórica do conhecimento neuroanatômico a respeito da superfície cerebral e das correlações topográficas cranioencefálicas, o advento da microneurocirurgia e as recentes contribuições da ressonância magnética.
Fratura traumática da coluna torácica limitada entre T1 e T10
Authors: Antunes Filho Gibrail Dib , Alliez Jean Roch , Kaya Jean Marc , Reynier Yves , Alliez Bernard
Published: January 2018

Objetivo: Estudo retrospectivo de uma série de 79 pacientes com fratura traumática da coluna torácica, limitada entre T1 e T10, hospitalizados entre 1995 e 2004 no Serviço de Neurocirurgia do Centro Hospitalar Universitário (CHU), Norte de Marseille, França. Métodos: As fraturas foram classificadas de acordo com a classificação da AO (Arbeitsgemeinschaft für Osteosynthesefragen) e o quadro neurológico por meio da classificação de Frankel na hospitalização, aos seis meses e um ano. Resultados: A etiologia mais frequente das fraturas foram os acidentes automobilísticos (68,3%), e o tipo de fratura, o B (54,4%); 57 pacientes foram considerados politraumatizados e 82,3% apresentavam lesão medular. O tratamento cirúrgico foi empregado em 96,2% dos casos, sendo a via posterior a mais utilizada com objetivo de estabilização, descompressão medular, correção do alinhamento da coluna, diminuição da dor e mobilização precoce. Conclusão: As incidências, as causas, os tipos de fraturas e os manejos destas foram analisados e comparados com a literatura e os resultados confirmaram a gravidade das lesões neste segmento da coluna, o número elevado de lesões associadas, a raridade de recuperação neurológica, assim como o benefício do tratamento cirúrgico por via posterior.
Motor function evaluation of hydrocephalus children
Authors: de Melo Costa Aida Carla Santana , Pereira Carlos Umberto , Farias Cândido Edna Aragão
Published: January 2018

Objectives: To evaluate the kinetic functional condition of children with hydrocephalus; to identify the condition of the muscle tone; to verify the static and dynamic functional activities; and to verify the association between tone changes and functional activities. Method: A cross-sectional, descriptive, exploratory and field study, using qualitative and quantitative approach, performed at the University Hospital in Aracaju city, from August 2009 to March 2010. Results: From 50 evaluated children, 30 (60%) had hypertonia; 10 (20%) were hypotonic; and 10 (20%) did not show muscle tone alteration. The age average was considerably lesser in hypertonic children and higher in hypotonic and without tone alteration children. The average of carried through surgeries was more expressive in hypertonic children. Motor sequels had been present in 92% of the sample. The static functional activities, as well as dynamic functional activities, were lower in hypertonic children (p < 0,0001) and higher in hypotonic and normal tone children. Conclusions: Muscle tone exacerbation is more present in hydrocephalus children and motor function is impaired, being the neuropsychomotor development delayed more evident in spastic children group and less pronounced in children with normal muscle tone.
Aneurismas intracranianos gigantes: aspectos morfológicos, clínicos e operatórios
Authors: dos Santos Marcio Luiz Tostes , dos Santos Rosângela Minto Tostes , Spotti Antonio Ronaldo , Tognola Waldir Antônio
Published: January 2018

Aneurismas intracranianos gigantes são definidos como aqueles em que o seu maior diâmetro ultrapassa 25 mm, sendo considerados entidade clínico-patológica que difere dos aneurismas de diâmetro menor quanto a incidência de ruptura, apresentação clínica e dificuldade de terapêutica. O tratamento do aneurisma gigante pode ser conservador, endovascular ou neurocirúrgico, e essa decisão depende de fatores como localização anatômica e características do aneurisma, condição médica, idade do doente, habilidades cirúrgicas e possibilidade de tratamento endovascular ou bypass. Apesar de o avanço no conhecimento da patogenia, hemodinâmica, morfologia, de a melhoria nos métodos de diagnóstico por imagem e de o desenvolvimento de técnicas endovasculares e microcirúrgicas terem possibilitado melhor resultado de tratamento, aneurismas gigantes apresentam prognóstico ruim e continuam desafiando os limites de técnicas neurocirúrgicas.
Lesões olfatórias pós-traumáticas
Authors: Cannoni Luiz Fernando , Haddad Luciano , Saade Nelson , Esteves Veiga José Carlos
Published: January 2018

Objetivo: Documentar a incidência de lesões traumáticas do nervo olfatório, assim como a etiologia traumática; correlacionar as lesões do nervo olfatório com achados radiológicos (lesões cranianas e intracranianas) e estudar lesões múltiplas de nervos cranianos. Métodos: Vinte e quatro pacientes admitidos no Serviço de Emergência da Santa Casa de Misericórdia de São Paulo com lesão traumática do nervo olfatório foram incluídos. Os pacientes foram divididos em três grupos, de acordo com o escore da escala de coma de Glasgow (ECG): trauma leve (ECG de 13 a 15), moderado (ECG de 9 a 12) e grave (ECG de 3 a 8), assim como em diferentes graus de lesão do olfatório, como hiposmia, anosmia e parosmia, distribuição quanto a gênero, presença de fraturas, lesões intracranianas, fístulas liquóricas e mecanismo de trauma. Resultados: Dos 24 casos, 15 lesões ocorreram em conjunto com outros nervos cranianos e em nove casos houve lesão exclusiva do nervo olfatório. O atropelamento foi a causa mais comum de lesão do nervo olfatório de forma isolada, assim como nas lesões de múltiplos nervos. Hematomas extradurais foram as lesões intracranianas mais frequentes e a ausência de fraturas predominou nos indivíduos estudados. Conclusão: Neuropatia traumática do olfatório deve ser pesquisada na admissão do paciente (quando possível), sobretudo quando houver evidência de traumas frontais ou occipitais.
Spinous process fractures after chiropractic massage in a previously healthy subject
Authors: Botelho Ricardo Vieira , Fernandes de Oliveira Matheus , Sousa Ulysses Oliveira , Rotta José Marcus
Published: January 2018

Increasing available alternative therapies to the treatment of back pain and sometimes difficult access to specialized medical evaluations allowed a widespread use of alternative therapies for the treatment of back pain. We describe a case with a consequence of massage therapy in a patient with initial symptoms of back pain resulting in spinous process fractures. She promptly searched medical attendance and cervical plain radiograph revealed avulsion of spinous processes of C6 and C7 in their outer third. Due to benign nature of lesion, without evidence of instability and spinal cord injury, the subject was managed conservatively, with application of a Philadelphia collar and analgesic medication. We reinforce the need of medical attention before beginning any therapeutic method in order to identify previous alterations and plan an adequate programming.
Vertebrobasilar insufficiency caused by cervical aneurysmal bone cyst – Case report
Authors: Vale Benjamim Pessoa , Lima Eduardo Leitão de Almeida , Mourão Barreto Ana Clara , Macedo Luciano Arruda
Published: January 2018

Aneurysmal bone cysts (ABC) are benign bone tumors of relatively rare occurrence. Most of the lesions occur at long bones, vertebrae and flat bones. However, the cervical vertebrae involvement is uncommon. Occasionally, the ABCs compress the spinal cord and nerve roots. Depending on the level of involvement and the extent of spinal cord compression, a wide variety of neurological symptoms and signs may be noted later, ranging from mild radiculopathy to complete paraplegia or tetraplegia. A case of aneurysmal bone cyst involving the second and third cervical vertebrae in a 15 years old patient, causing compression of the right vertebral artery and subsequent vertebrobasilar insufficiency is reported. We also discuss the clinical manifestations of the vertebrobasilar insufficiency, of the spinal compression, and the surgery treatment performed in this case.
XI cranial nerve cervical schwannoma – Case report
Authors: Brock Roger Schmidt , Barroso Marcelo Viana da Silva , Neville Iuri Santana , Teles Gomes Marcos Queiroz , Cardoso Alberto Capel , Taricco Mario Augusto , Teixeira Manoel Jacobsen
Published: January 2018

Cisternal spinal accessory schwannoma are still a rare condition without neurofibromatosis with only 32 cases reported so far. We describe a cisternal accessory schwannoma presented in a 36-year-old woman with posterior cervical pain and cervical mieolopaty, defined by grade IV tetraparesia. A suboccipital craniectomy with C1 posterior arch resection was performed. During microsurgical dissection together with electrophysiological monitoring and nerve stimulation tumor was identified as having the spinal accessory root as its origins. Carefully intraneural dissection was then performed with complete lesion removal, histopatological examination confirmed the hypothesis of schwannoma. The patient was free from pain and improved her neurological status with no accessory nerve palsy. Complete surgical resection is indicated for such lesions and can be achieved with good outcome.
Nanoscale metal-InGaAs contacts with ultra-low specific contact resistivity: Improved interfacial quality and extraction methodology
Authors: Masudy-Panah Saeid , Wu Ying , Lei Dian , Kumar Annie , Yeo Yee-Chia , Gong Xiao
Published: January 2018

To enable heterogeneous integration of InGaAs based transistors with Si complementary metal–oxide–semiconductor (CMOS) devices, metal contacts to n+-InGaAs need to have high thermal stability for CMOS process compatibility and ultra-low contact resistance to achieve good device performance. In this work, n+-InGaAs contacts with ultra-low contact resistivity ρc based on refractory metals such as molybdenum (Mo) were realized. Use of refractory metal contacts achieves good thermal stability. An improved process that eliminates oxide between the metal and n+-InGaAs by using an in situ Ar+-plasma treatment prior to metal deposition achieves ultra-low ρc. Furthermore, a nano-scale transmission line method (nano-TLM) structure with significantly reduced parasitic leakage was designed and fabricated to improve the ρc extraction accuracy. The improved test structure introduces a SiO2 isolation layer between Mo and InGaAs outside the active or mesa region to eliminate a parallel leakage path that is present in other nano-TLM structures reported in the literature.
Influence of impurities on the high temperature conductivity of SrTiO3
Authors: Bowes Preston C. , Baker Jonathon N. , Harris Joshua S. , Behrhorst Brian D. , Irving Douglas L.
Published: January 2018

In studies of high temperature electrical conductivity (HiTEC) of dielectrics, the impurity in the highest concentration is assumed to form a single defect that controls HiTEC. However, carrier concentrations are typically at or below the level of background impurities, and all impurities may complex with native defects. Canonical defect models ignore complex formation and lump defects from multiple impurities into a single effective defect to reduce the number of associated reactions. To evaluate the importance of background impurities and defect complexes on HiTEC, a grand canonical defect model was developed with input from density functional theory calculations using hybrid exchange correlation functionals. The influence of common background impurities and first nearest neighbor complexes with oxygen vacancies (vO) was studied for three doping cases: nominally undoped, donor doped, and acceptor doped SrTiO3. In each case, conductivity depended on the ensemble of impurity defects simulated with the extent of the dependence governed by the character of the dominant impurity and its tendency to complex with vO. Agreement between simulated and measured conductivity profiles as a function of temperature and oxygen partial pressure improved significantly when background impurities were included in the nominally undoped case. Effects of the impurities simulated were reduced in the Nb and Al doped cases as both elements did not form complexes and were present in concentrations well exceeding all other active impurities. The influence of individual impurities on HiTEC in SrTiO3 was isolated and discussed and motivates further experiments on singly doped SrTiO3.
The influence of ion hydration on nucleation and growth of LiF crystals in aqueous solution
Authors: Lanaro G. , Patey G. N.
Published: January 2018

Molecular dynamics (MD) simulations are employed to investigate crystal nucleation and growth in oversaturated aqueous LiF solutions. Results obtained for a range of temperatures provide evidence that the rate of crystal growth is determined by a substantial energy barrier (∼49 kJ mol−1) related to the loss of water from the ion hydration shells. Employing direct MD simulations, we do not observe spontaneous nucleation of LiF crystals at 300 K, but nucleation is easily observable in NVT simulations at 500 K. This contrasts with the NaCl case, where crystal nucleation is directly observed in similar simulations at 300 K. Based on these observations, together with a detailed analysis of ion clustering in metastable LiF solutions, we argue that the ion dehydration barrier also plays a key role in crystal nucleation. The hydration of the relatively small Li+ and F− ions strongly influences the probability of forming large, crystal-like ion clusters, which are a necessary precursor to nucleation. This important factor is not accounted for in classical nucleation theory.
Unusual strain glassy phase in Fe doped Ni2Mn1.5In0.5
Authors: Nevgi R. , Priolkar K. R.
Published: January 2018

Fe doped Ni2Mn1.5In0.5, particularly, Ni2Mn1.4Fe0.1In0.5, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss which obeys the Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both frequency dependence and ergodicity breaking are characteristics of a strain glassy phase and occur due to the presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non-interacting with other strain domains due to the presence of Fe impurities.
Addressing limitations of photoluminescence based external quantum efficiency measurements
Authors: Paduthol Appu , Juhl Mattias Klaus , Trupke Thorsten
Published: January 2018

The spectral response of photoluminescence is a contactless method that provides a measurement of the relative external quantum efficiency of silicon solar cells and wafers. This method is accurate only if the measured luminescence originates from the radiative recombination of voltage dependent carriers. This paper investigates the impact of luminescence from voltage independent carriers in heavily diffused regions and other spurious sources of luminescence, such as luminescence from dielectric layers. A method, based on partial shading, is then demonstrated to record luminescence from only the voltage dependent carriers. This method is shown to provide accurate relative external quantum efficiency on cells and partially processed wafers. The relevance of the dependence of the measured data on the angular distribution of the incident light is demonstrated in this context, which explains errors in previously published data.
Effects of dispersion interactions on the structure, polarity, and dynamics of liquid-vapor interface of an aqueous NaCl solution: Results of first principles simulations at room temperature
Authors: Roy Choudhuri Jyoti , Chandra Amalendu
Published: January 2018

The effects of dispersion interaction on the structure, polarity, and dynamics of liquid-vapor interface of a concentrated (5.3M) aqueous NaCl solution have been investigated through first-principles simulations. Among the structural properties, we have investigated the inhomogeneous density profiles of molecules, hydrogen bond distributions, and orientational profiles. On the dynamical side, we have calculated diffusion, orientational relaxation, hydrogen bond dynamics, and vibrational spectral diffusion of molecules. The polarity of water molecules across the interface is also calculated. Our simulation results are compared with those when no dispersion corrections are included. It is found that the inclusion of dispersion correction predicts an overall improvement of the structural properties of liquid water. The current study reveals a faster relaxation of hydrogen bonds, diffusion, and rotational motion for both interfacial and bulk molecules compared to the results when no such dispersion corrections are included. The dynamics of vibrational frequency fluctuations are also calculated which capture the relaxation of hydrogen bond fluctuations in the bulk and interfacial regions. Generally, the hydrogen bonds at the interfaces are found to have longer lifetimes due to reduced cooperative effects.