bluuebunny/crossref_metadata_2025 huggingface dataset:
Percepção dos Docentes Quanto à Abordagem da Resolução de Problemas nos Livros Didáticos de Matemática
Authors: Kliemann Geovana Luiza , Dullius Maria Madalena
Published: March 2018

Esta investigação visou diagnosticar como e para que os professores do 1º ano do Ensino Médio de seis escolas estaduais do Vale do Taquari usam os livros didáticos de Matemática, e identificar suas percepções em relação à abordagem da resolução de problemas neste material. Para atingir os objetivos, foram realizadas entrevistas com dez professores de Matemática, as quais foram gravadas e, após análise, resultaram em categorias. Como resultados, é possível destacar que os livros didáticos são utilizados pelos professores sob diferentes aspectos, principalmente para retirar exercícios e problemas que estão relacionados aos conteúdos que exploram em suas aulas e que apresentam algumas inovações, mas os problemas vêm, na maioria das vezes, vinculados a algum conteúdo específico. Considera-se, portanto, que o livro didático auxilia o professor e permite reflexões que possibilitam a ele realizar uma abordagem voltada à metodologia da resolução de problemas, porém não é suficiente para prática escolar.Palavras-chave: Professores de Matemática. Livro didático. Resolução de problemas.AbstractThis research aimed to diagnose how and what for teachers of the 1st year of High Schools from six public schools in Vale do Taquari use Mathematics textbooks, and to identify their perceptions regarding to the approach of problem solving in this material. In order to achieve the objectives, ten Mathematics teachers were interviewed and recorded and, after analysis, their speeches resulted in categories. As a result, it is possible to point out that textbooks are used by teachers under different aspects and that they present some innovations, but the problems are, in most cases, linked to some specific content. It is considered, therefore, that the textbook helps the teacher and allows reflections that make possible to him an approach focused on the problem solving methodology, but is not enough for school practice.Keywords: Math teachers. Textbook. Problem Solving.
A Interação de Aspectos Algorítmicos, Intuitivos e Formais e o Desenvolvimento de Processos do Pensamento Matemático Avançado na Aprendizagem Matemática
Authors: Vieira William , Giusti de Souza Vera Helena , Imafuku Roberto Seidi
Published: March 2018

Apresentamos uma situação de aprendizagem matemática na qual pode-se observar o desenvolvimento de processos do Pensamento MatemáticoAvançado como representação, tradução,  visualização e generalização e o papel que a interação de aspectos algorítmicos, intuitivos e formais desempenha no desenvolvimento desses processos.Palavras-chave: Pensamento Matemático Avançado; Aspectos algorítmicos, intuitivos e formais.AbstractWe present a situation of mathematics learning in which one can observe the development of Advanced Mathematical Thinking processes as representation, translation, visualization and generalization and the role the interaction of algorithmic, intuitive and formal aspects plays in the development of these processes.Keywords: Advanced Mathematical Thinking; Algorithmic, intuitive and formal aspects.
Reflections upon the Mandatory Internships on Mathematics Teacher Training Undergraduate Courses
Authors: Rosa Dalva Eterna Gonçalves , Magalhães Ana Paula De Almeida Saraiva
Published: March 2018

Abstract: this essay’s main objective is to present some of the results from a research which investigated the investigated the Mandatory Internship in Mathematics undergraduate teaching courses at a public university in the state of Goiás. Its goals were to comprehend how this specific curricular component encouraged the teachers-to-be’s reflective practices. The subjects analyzed were seven professors from the Mathematics teacher training program in seven different university units. They worked with MI in 2008 or 2009. The theoretical and methodological qualitative approach made this paper, and its documental analysis of surveys and reflective intervivews, possible. The context and data diagnosed that, on Mathematics teacher training undergraduate courses, the development of reflective teaching practices are still timid and isolated.

Reflexões sobre o estágio supervisionado nos cursos de Licenciatura em Matemática

Resumo: este artigo tem o objetivo de apresentar alguns resultados de pesquisa realizada sobre o Estágio Supervisionado nos Cursos de licenciatura em matemática de uma universidade pública do estado de Goiás. O objetivo da pesquisa foi compreender se esse componente curricular tem provocado a prática reflexiva dos licenciandos. Os sujeitos foram sete professores de licenciatura em matemática de sete unidades universitárias dessa instituição, que trabalharam com o Estágio Supervisionado em 2008 ou 2009. O enfoque teórico-metodológico qualitativo possibilitou a análise documental, de questionários e entrevistas de caráter reflexivo. No contexto investigado, ações para o desenvolvimento de práticas reflexivas na formação de professores de Matemática ainda são tímidas e isoladas.
Education, Citizenship and the Environment
Authors: Silva Marcos Antônio da
Published: March 2018

Educação, Cidadania e Meio Ambiente
Factors of raised C-reactive protein as a potential determinant of Diabetic patients and Risk factor for Coronary Heart Disease
Authors: Kumar Sharma Sushil , Parag Rastogi
Published: March 2018

Elevated C-reactive protein (CRP) levels have previously been described before the onset of type 1 diabetes and gestational diabetes. We hypothesized that inflammation, as reflected by elevated CRP levels, can help predict development of islet autoimmunity or type 1 diabetes. The outcome of this research is to establish potential determinants of raised CRP concentrations in type 1 diabetic patients. Sensitive assay showed ‘low-level’ CRP concentrations in 147 type 1 patients (83M, 64F, median age 30 years, range 13–67). We have done step by step variant examination to relate these CRP levels to known cardiovascular risk factors and demographic data. Only four patients had established Coronary Heart Disease (median CRP 3.43 mg/l vs. 0.85 mg/l, p=0.035). In subjects without overt CHD, multivariate analysis revealed increase in subject age (p=0.0027), BMI (p=0.001) and HbA1 (p=0.013) to be associated with a higher CRP concentration, as was female sex (p=0.025) and a history of CHD in a first-degree relative (p=0.018, n=58). Elevated CRP levels were positively associated with cardiovascular and renal risk factors: age, body mass index, blood pressure, serum cholesterol level, smoking, plasma glucose level and elevated urinary albumin excretion and presence of hypertension were unrelated. This research work advises that certain of the risk factors connected with CHD in type 1 patients are also individually predictive of high CRP concentrations. The reasons for this, and whether intervention would prove valuable, require further analysis
Effects of radio-frequency electromagnetic radiations (RF-EMR) on cerebral cortex of albino rats-a light and electron microscopic study
Authors: Taufiq Dr.faisal , Srivastava Dr. Mohit
Published: March 2018

Background: Since the introduction of mobile phones in the late eighties, many studies have raised concerns about the possible adverse effects on health, as a result of the exposure to RF and microwave electromagnetic fields as RF-EMR can penetrate deep into organic tissues and get absorbed producing many biological effects in human body. Brain is involved in very important functions and RF-EMR might have damaging effects on its different parts. The present study was undertaken with an aim to study effects of radio-frequency electromagnetic radiations (RF-EMR) emitted by mobile phones on cerebrum in albino rats under light and electron microscopy and to evaluate such changes after exposure to graded dose of RF-EMR

Material and methods: The present study was carried out on twenty four adult albino rats of either sex weighing 180-200 grams each. The animals were divided into four groups: 1 control and 3 experimental and were exposed to RF-EMR via complete missed calls of 45 seconds duration each. Both the experimental and control groups were then sacrificed and cerebral cortex was isolated for tissue processing. The processed tissues were then studied under light microscope (Hematoxylin & Eosin Staining) and Transmission Electron Microscopy (TEM).    

Results: Light microscopic findings of the present study showed that cellular size of neuronal cells in pyramidal layer of cerebral cortex, neurons of hippocampus and some granular layers in cerebral cortex of RF-EMR exposed rats decreased in compare to control groups. Individual cells could be seen with condensed cytoplasm and nucleus. Electron microscopic findings revealed individual shrunken cells with condensed cytoplasm and nucleus.

Conclusion: From the findings of the present study it appears pertinent that in order to protect the population living around base stations and users of mobile handsets, governments and regulatory bodies adopt safety standards, which translate to limits on exposure levels below a certain value and efforts are underway to harmonize the different standards in existence.
Estrat�gias de ensino-aprendizagem com apoio de tecnologias para a forma��o interdisciplinar e integral em sa�de
Authors: De Oliveira Fl�via , Leiko Takamatsu Goyata Sueli , Das Gra�as Martins Marlene , De Abreu Nery Marcos , Costa Valcanti Carolina
Published: March 2018

Objetivo: Descrever e avaliar o desenvolvimento de um ambiente virtual de aprendizagem para a forma��o interdisciplinar e integral em sa�de. M�todos: Pesquisa descritiva, do tipo qualitativa, de avalia��o de um curso, com encontros presenciais e � dist�ncia pela plataforma Moodle, numa amostra de 20 estudantes de cinco cursos da �rea da sa�de. Para an�lise, foram consideradas as fontes de dados de avalia��o cognitiva do aluno, aplica��o de question�rio de avalia��o e o grupo focal. Resultados: As ferramentas wiki e f�rum auxiliam na forma��o interdisciplinar em sa�de por permitirem a constru��o colaborativa do conhecimento entre diferentes categorias profissionais da �rea da sa�de. Conclus�o: As estrat�gias de ensino e de aprendizagem utilizadas neste estudo, por possibilitarem a constru��o do conhecimento colaborativo, demonstraram ser importantes ferramentas que podem auxiliar no processo de forma��o interdisciplinar e integral em sa�de.
Perfil epidemiol�gico da mortalidade por causas externas entre benefici�rios de planos de sa�de no Brasil
Authors: Batista Josemar , Barreto Mayckel Da Silva , Merino Maria De F�tima Garcia Lopes , Fracasso Nathalia Vasconcelos , Baldissera Vanessa Denardi Antoniassi
Published: March 2018

Objetivos: descrever o perfil epidemiol�gico e a distribui��o dos �bitos notificados por causas externas em benefici�rios de planos de sa�de no Brasil entre os bi�nios 2006-2007 e 2008-2009. M�todo: estudo epidemiol�gico e descritivo, cujos dados foram acessados no Sistema de Informa��es sobre Mortalidade em Sa�de Suplementar em janeiro de 2016. Foram analisados por estat�stica descritiva, varia��es percentuais e raz�es de propor��o entre os bi�nios. Resultados: evidenciou-se a notifica��o de 19.514 �bitos, no per�odo 20062007 e 20.796 entre 2008-2009, com caracter�sticas similares, segundo as vari�veis sociodemogr�ficas, sendo que os �bitos ocorreram, principalmente, entre homens em idade produtiva (20 e 59 anos de idade) nos dois bi�nios (72,75%; 71,61%). Os �bitos por causas acidentais (transporte, quedas, afogamentos/submers�es) foram prevalentes nos per�odos (51,17%; 51,28%). Os registros de �bitos por causas externas entre benefici�rios de planos de sa�de se reduziram no Brasil, passando de 8,73% em 2006-2007 para 8,35% em 20082009, com varia��o percentual negativa de -4,35. Entretanto, aumentaram as notifica��es relacionadas com as quedas e les�es autoprovocadas (varia��o percentual positiva de 9,63 e 2,32, respectivamente). Conclus�o: observou-se altera��o da distribui��o espacial dos �bitos por causas externas entre benefici�rios de planos de sa�de, permitindo an�lises para subsidiar medidas preventivas.
Crisis de la democracia representativa: alternativas participativas o democracia directa con medios electrónicos = Crisis of representative democracy: participatory alternatives or direct democracy with electronic media
Authors: Martino Antonio A.
Published: March 2018

Resumen: El artículo analiza la actual crisis de la democracia representativa criticando la tesis según la cual aquel país que instauraba una democracia y mantenía mínimos índices de solidez económica y social aseguraba su mantenimiento.  A tal fin, inicia la explicación de la crisis de la democracia tout court y, después, va analizando las alternativas que se ofrecen a la democracia representativa. Así, aborda directamente la democracia directa para mostrar alguno de sus elementos más relevantes, sobre todo con medios electrónicos, y muestra posteriormente su reforzamiento.Palabras clave: Democracia, representación, democracia directa, democracia participativa.Abstract: The article presents the current crisis of representative democracy criticizing the thesis by which a country that reached democracy and maintained minimum rates of economic and social solidity had it insured. It explains first the crisis of democracy tout court and then analyzes the alternatives offered to representative democracy. It directly focuses on direct democracy to show important elements of it, above all with electronic means, to show later that elements of participatory democracy will be reinforced in the interim. Keywords: Democracy, representation, direct democracy, participatory democracy.
La armonización de la legislación penal en América Central = The harmonisation of criminal legislation in Central America
Authors: Álvarez García Francisco Javier
Published: March 2018

Resumen: La efectividad en la lucha contra la, especialmente, criminalidad organizada precisa inexcusablemente de la cooperación internacional, sin embargo condición de ésta, especialmente en un escenario tan complicado como es Centroamérica, de un acercamiento de las legislaciones de los diversos estados en términos de “armonización”. La experiencia del autor en la armonización de numerosos tipos penales en el ámbito del Sistema de Integración Centroamericano (SICA) es lo que se ha plasmado, sintéticamente, en este trabajo.Palabras clave: Armonización, criterios de armonización, armonización máxima o mínima, principio de legalidad, cooperación internacional penal, organizaciones criminales.Abstract: The effectiveness in the fight against organized criminality needs compulsory international cooperation. However, as a previous condition, it needs the convergence of legislations form different states in terms of “harmonisation”, mainly in the so complex scenario from Central America. This paper incorporates the author’s experience about preparing the harmonisation of a large number of criminal figures at the Central American Integration System (SICA).Keywords: Harmonisation, harmonisation criteria, maximum or minimum harmonisation, rule of law, criminal international cooperation, criminal organizations.
Presidencialismo = Presidential System
Authors: Arango Restrepo Ana Catalina
Published: March 2018

Resumen: El sistema presidencial ha sido objeto de un intenso debate en América Latina, primero, por entender algunos que los regímenes de la región eran una copia “desviada” o “atrofiada” del modelo estadounidense y más tarde, por ser identificada esta forma de gobierno como uno de los factores que explicaba la caída en cadena de sus democracias. En esta voz se retoma el debate que abrió Linz en los años ochenta sobre el desempeño de los sistemas presidenciales, con el objeto de rescatar aquellos elementos que continúan siendo relevantes para acercarse al estudio del presidencialismo. A partir de las principales variables que, según esta discusión, sirven para determinar la posición que ocupa el ejecutivo en el entramado institucional, esto es, las facultades legislativas que la Constitución le otorga al presidente y la configuración del sistema electoral y de partidos, se recogen los elementos que permiten distinguir tres categorías dentro de los sistemas presidenciales: “hiperpresidencialismo”, presidencialismo “moderado” y presidencialismo “atenuado”.Palabras clave: Formas de gobierno, gobernabilidad, variaciones del presidencialismo.Abstract: The presidential system has been a subject of intense debate in Latin America, first because some authors claimed that the regimes in the region were a "deviant" or "atrophied" copy of the American model and later because this form of government was identified as one of the factors that explained the collapse of their democracies. This article examines the debate opened by Linz in the eighties over the performance of presidential systems, aiming to bring up some of the elements that are still relevant for studies over presidentialism. Taking into account the main variables that according to these debates determine the role of the government within the institutional framework, it distinguishes among three of its variations: "hyperpresidentialism", "moderate" presidentialism and "attenuated" presidentialism.Keywords: Forms of government, governability, variations of presidential systems.
Referéndum = Referendum
Authors: San Vicente Feduchi Jorge
Published: March 2018

Resumen: El referéndum, entendido como “la oportunidad de que los electores participen en el proceso de toma de decisión votando sobre una cuestión más o menos específica y determinada” (Uleri, 1996, p. 2), ha tomado históricamente infinidad de formas, con desenlaces diversos dependiendo del contexto en el que ha sido desarrollado. No obstante, tanto la proliferación como la relevancia que este mecanismo ha adquirido en las democracias contemporáneas plantean nuevas vías de estudio, entre las que se encuentra su potencial para encauzar una participación efectiva frente a su reducido uso tradicional como mero mecanismo de legitimación política. El artículo tiene como objetivo plantear las bases para la discusión del uso referéndum en relación a una concepción de la democracia que se extienda más allá de la lógica de la representatividad.Palabras clave: Referéndum, democracia directa, democracia representativa, participación, representación, iniciativa.Abstract: The referendum, understood as “the opportunity for electors to participate in a decision-making process by voting on an issue more or less specific and determined” (Uleri, 1996, p. 2), has historically taken an infinite amount of shapes, with diverse outcomes depending on the context in which it has taken place. However, the recent surge both in its use and its relevance in contemporary democracies raises new research lines, among which is its potential to channel an effective participation in contrast to its traditional use as a simple legitimation mechanism. The article’s objective is to set the foundation for a discussion on the use of referendums in relation to a conception of democracy that goes beyond the logic of representation.Keywords: Referendum, direct democracy, representative democracy, participation, representation, initiative.
Violencia escolar = School violence
Authors: Zurita Rivera Úrsula
Published: March 2018

Resumen: En las sociedades contemporáneas se observa una multiplicidad de acciones emprendidas en numerosos ámbitos y sectores, bajo la responsabilidad de un amplio abanico de actores de diferente escala, con el fin de prevenir, atender y eliminar la violencia escolar. Dados los graves efectos que este problema provoca no solo entre los individuos e instituciones directamente involucradas, sino también en el fortalecimiento democrático y el ejercicio pleno de los derechos humanos, la prevención de la violencia en las escuelas es una tarea apremiante. Frente al despliegue masivo de estrategias de intervención, a los abundantes estudios realizados en distintos campos disciplinares y a su incorporación en diversas agendas de políticas públicas, es escaso el análisis de las implicaciones que esas estrategias tienen en los principios de autoridad, legalidad y legitimidad en las escuelas. Emprender esta tarea es fundamental, ya que buena parte de las rutas trazadas en el presente para afrontar la violencia escolar –como la creación y aplicación de leyes específicas, el rediseño de acuerdos nacionales, lineamientos para el sistema educativo, manuales para la convivencia hasta los reglamentos escolares, entre otros instrumentos– han afectado dichos principios desconociendo los resultados y efectos que tienen en la conformación, reproducción e, incluso, perpetuación de la violencia escolar.Palabras clave: Violencia escolar, autoridad, legalidad, legitimidad, reglamentos escolares, fragmentación de la autoridad.Abstract: In contemporary societies, a multiplicity of actions has been taken in different areas and sectors under the responsibility of a wide range of actors on different scales, in order to prevent, attend and eliminate school violence. Since the serious effect of this problem, not only among the individuals and institutions directly involved, but also for the strengthening of democracy and the full exercise of human rights, combating violence in schools is an urgent task. Despite of the massive deployment of intervention strategies, the numerous studies carried out in different academic fields and their inclusion on policy agenda, the implications that these strategies have on the principles of authority, legality and legitimacy in schools has barely been analyzed. This task is essential, given that many of the paths outlined currently to address school violence –such as the creation and application of specific laws, the redesign of national agreements, the guidelines for the education system, the manuals for school coexistence, among other instruments– have affected these principles and have ignored the results and implications that they have in the conformation, reproduction and even perpetuation of this problem.Keywords: School violence, authority, legality, legitimacy, school rules, fragmentation of authority.
Lobba P., Mariniello T. (eds.) (2017), Judicial Dialogue on Human Rights. The Practice of International Criminal Tribunals
Authors: Rodríguez Rodríguez Jorge
Published: March 2018

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A Study of the Network Analysis in Enhancing the Managerial Efficiency of Dairy Co-Operative Personnels in Uttar Pradesh
Authors: Kumar Ashok
Published: March 2018

The dairy organization represents a complex system is highly departmentalized and specialized at various levels, which has necessitated a great deal of co-ordination and interaction among its employees through an efficient organizational communication network. Net work analysis between management and employees at various levels of management plays an important role in achievement of the organizational effectiveness. The amount of upward communication was higher than downward communication as well as horizontal communication. The horizontal communication was also observed more than downward communication and hence, the efforts are required to attract the attention in this directionality the top management so that the management personnel could raise downward communication. Various types of communication messages i.e. informative, instructive, influencive, evaluative and counseling play a vital and indispensable role in management. The network analysis directly assist the management system in achieving the goals of the organization and also help in creating a congenial environment of better functioning by the incumbents in the organization.
Foam Generation with Flow Rate: Effect of Surfactant Concentration and Gas Fraction
Authors: Yu G. , Rossen W. R. , Vincent-Bonnieu S.
Published: March 2018

The propagation of foam in an oil reservoir depends on the creation and stability of the foam in the reservoir, specifically the creation and stability of foam films, or lamellae. As the foam propagates far from in injection well, superficial velocity and pressure gradient decrease with distance from the well. Experimental (Friedmann et al., 1994) and theoretical (Ashoori et al., 2011) studies relate concerns about foam propagation at low superficial velocity to the minimum velocity for foam generation near the well (Rossen and Gauglitz, 1990; Gauglitz et al., 2002). The objective of this work is to measure the impact of surfactant concentration and gas fractional flow on foam generation. Theory (Rossen and Gauglitz, 1990; Kam and Rossen, 2003) relates foam generation to gas fractional flow and, indirectly, to the stability of foam films, or lamellae, which in turn depends on surfactant concentration (Apaydin and Kovcsek, 2001). However, the link between foam generation and surfactant concentration has not been established experimentally.

In our experiments, nitrogen foam is generated in a core of Bentheimer sandstone. The foamgeneration experiments consist of measuring the critical velocity for foam generation as a function of gas fractional flow at three surfactant concentrations well above the critical micelle concentration. Experimental results show that critical velocity decreases with increasing liquid fraction, as shown by previous foam generation studies (Rossen and Gauglitz, 1990; Friedmann et al., 1991). Additionally, our results show that the critical velocity decreases with increasing surfactant concentration, far above the CMC. We also propose a workflow for screening out the experimental artifacts that can distort the trigger velocity.
Spectrophotometric determination of triclosan based on diazotization reaction: response surface optimization using Box–Behnken design
Authors: Kaur Inderpreet , Gaba Sonal , Kaur Sukhraj , Kumar Rajeev , Chawla Jyoti
Published: March 2018

A spectrophotometric method based on diazotization of aniline with triclosan has been developed for the determination of triclosan in water samples. The diazotization process involves two steps: (1) reaction of aniline with sodium nitrite in an acidic medium to form diazonium ion and (2) reaction of diazonium ion with triclosan to form a yellowish-orange azo compound in an alkaline medium. The resulting yellowish-orange product has a maximum absorption at 352 nm which allows the determination of triclosan in aqueous solution in the linear concentration range of 0.1–3.0 μM with R2 = 0.998. The concentration of hydrochloric acid, sodium nitrite, and aniline was optimized for diazotization reaction to achieve good spectrophotometric determination of triclosan. The optimization of experimental conditions for spectrophotometric determination of triclosan in terms of concentration of sodium nitrite, hydrogen chloride and aniline was also carried out by using Box–Behnken design of response surface methodology and results obtained were in agreement with the experimentally optimized values. The proposed method was then successfully applied for analyses of triclosan content in water samples.
Build-up and characterisation of pollutants on urban impervious surfaces
Authors: Djukić Aleksandar , Lekić Branislava , Rajaković-Ognjanović Vladana , Naunovic Zorana , Prodanović Dušan
Published: March 2018

This paper presents the results of the investigation of pollutant build-up on impervious surfaces of a parking lot in Belgrade, Serbia during the summer months. Contaminant build-up was found to be greater on asphalt surfaces directly exposed to vehicular traffic than on concrete walkways. The difference in the amounts of accumulated pollutants between asphalt and concrete were significant: for total solids (TS), total suspended solids (TSS), chemical oxygen demand (COD), heavy metals and total phosphorus (TP) accumulations were two to three times higher, while only 30% higher for total nitrogen (TN) and anions. Build-up of most of the measured parameters was best described by power functions. The highest surface loads were found for solids, COD, iron and zinc. A strong correlation was found between turbidity, TS, TSS, COD, heavy metals and phosphorus, while conductivity, nitrates and nitrites were weakly correlated to other parameters.
Experimental observation of Dyakonov plasmons in the mid-infrared
Authors: Takayama O. , Dmitriev P. , Shkondin E. , Yermakov O. , Panah M. , Golenitskii K. , Jensen F. , Bodganov A. , Lavrinenko A.
Published: March 2018

AbstractIn this work, we report on observation of Dyakonov plasmons at an interface with a hyperbolic metamaterial in the mid-IR. The hyperbolic metamaterial is implemented as a CMOS-compatible high aspect ratio grating structure with aluminium-doped ZnO (AZO) ridges grown by atomic layer deposition in deep trench silicon matrix. The dispersion of Dyakonov plasmons is characterized by the attenuated total reflection method in the Otto configuration. We demonstrate that Dyakonov plasmons propagate in a broad range of directions (a few tens of degrees) in contrast to the classical Dyakonov surface waves (about one tenth of degree). The obtained results provide useful guidelines for practical implementations of structures supporting Dyakonov plasmons in the mid-IR.
Localization-delocalization transition in disordered one-dimensional exciton-polariton system
Authors: Larionov A.V. , Brichkin A.S. , Hofling S. , Kulakovskii V.D.
Published: March 2018

AbstractThe transition from the delocalized to the localized state has been investigated in a quasi-onedimensional exciton-polariton system excited nonresonantly in GaAs-based microcavity wire with disordered potential. The photoexcited polariton condensate has been found to spread along the wire with а velocity exceeding 1 μm/ps. The propagation along the wire is provided by high energy polaritons. The LP localization length decreases with decreasing blue shift of LPs in the excited spot. The polariton condensate returns to the Bose glass state when the blue shift of the LP resonance at the excitation spot decreases below the critical level that depends on the potential disorder.
Photon echo from an ensemble of (In, Ga)As quantum dots
Authors: Babenko Ia.A. , Yugova I.A. , Poltavtsev S.V. , Salewski M. , Akimov I.A. , Kamp M. , Hofling S. , Yakovlev D.R. , Bayer M.
Published: March 2018

AbstractPhoton echo from trions and excitons in (In,Ga)As/GaAs quantum dots was studied theoretically and experimentally. Theoretical analysis allowed us to distinguish between photon echo signals from excitons and trions measured in the same range of wavelength using different polarization configurations of laser excitation. The theoretical predictions are in good agreement with the experimental data.
Quantum dynamics of a domain wall in the presence of dephasing
Authors: Castelnovo Claudio , Dykman Mark I. , Smelyanskiy Vadim N. , Moessner Roderich , Pryadko Leonid P.
Published: March 2018

AbstractWe compare quantum dynamics in the presence of Markovian dephasing for a particle hopping on a chain and for an Ising domain wall whose motion leaves behind a string of flipped spins. Exact solutions show that on an infinite chain, the transport responses of the models are nearly identical. However, on finitelength chains, the broadening of discrete spectral lines is much more noticeable in the case of a domain wall.
Влияние легирования на свойства аморфного гидрогенизированного кремния, облученного фемтосекундными лазерными импульсами
Authors: Денисова К.Н. , Ильин А.С. , Мартышов М.Н. , Воронцов А.С.
Published: March 2018

AbstractA comparative analysis of the effect of femtosecond laser irradiation on the structure and conductivity of undoped and boron-doped hydrogenated amorphous silicon ( a -Si: H) is performed. It is demonstrated that the process of nanocrystal formation in the amorphous matrix under femtosecond laser irradiation is initiated at lower laser energy densities in undoped a -Si: H samples. The differences in conductivity between undoped and doped a -Si: H samples vanish almost completely after irradiation with an energy density of 150–160 mJ/cm^2.
Влияние углерода на электрические свойства объемных композитов на основе окиси меди
Authors: Калинин Ю.Е. , Каширин М.А. , Макагонов В.А. , Панков С.Ю. , Ситников А.В.
Published: March 2018

AbstractThe effect of carbon filler on the electrical resistance and the thermopower of copper oxide-based composites produced by ceramic technology by hot pressing has been studied. It is found that the dependences of the electrical resistivity on the filler concentration are characteristic by S-like curves that are typical of percolation systems; in this case, the resistivity decreases more substantially as the carbon content increases as compared to the decrease in thermopower value, which is accompanied by the existence of the maximum of the factor of thermoelectric power near the percolation threshold. The studies of the temperature dependences of the resistivity and the thermopower at low temperatures show that, in the range 240–300 K, the predominant mechanism of the electrotransfer of all the composites under study is the hopping mechanism. At temperatures lower than 240 K, the composites with a nanocrystalline CuO matrix have a hopping conductivity with a variable hopping distance over localized states of the matrix near the Fermi level, which is related to the conductivity over intergrain CuO boundaries. A schematic model of the band structure of nanocrystalline CuO with carbon filler is proposed on the base of the analysis of the found experimental regularities of the electrotransfer.
Структура и свойства пленок SiO-=SUB=-x-=/SUB=-, полученных химическим травлением лент аморфного сплава
Authors: Федоров В.А. , Березнер А.Д. , Бескровный А.И. , Фурсова Т.Н. , Павликов А.В. , Баженов А.В.
Published: March 2018

AbstractThe structure and the physical properties of amorphous SiO_ x films prepared by chemical etching of an iron-based amorphous ribbon alloy have been studied. The neutron diffraction and also the atomicforce and electron microscopy show that the prepared visually transparent films have amorphous structure, exhibit dielectric properties, and their morphology is similar to that of opals. The samples have been studied by differential scanning calorimetry, Raman and IR spectroscopy before and after their heat treatment. It is found that annealing of the films in air at a temperature of 1273 K leads to a change in their chemical compositions: an amorphous SiO_2 compound with inclusions of SiO_2 nanocrystals (crystobalite) forms.
Магнитное состояние квазиупорядоченных сплавов Fe-Al с добавками Ga и B: магнитное фазовое расслоение и спиновый порядок
Authors: Воронина Е.В. , Иванова А.Г. , Аржников А.К. , Чумаков А.И. , Чистякова Н.И. , Пятаев А.В. , Королев А.В.
Published: March 2018

AbstractResults of structural, magnetic, and Mössbauer studies of quasi ordered alloys Fe_65Al_35 − x M_ x ( M _ x = Ga, B; x = 0, 5 at %) are presented. The magnetic state of examined structurally–single-phase alloys at low temperatures is interpreted from the viewpoint of magnetic phase separation. An explanation is proposed for the observed behavior of magnetic characteristics of Fe_65Al_35 and Fe_65Al_30Ga_5 in the framework of the model of two magnetic phases, a ferromagnetic-type one and a spin density wave. The boron-doped alloy Fe_65Al_30B_5 is shown to demonstrate behavior that is typical of materials with the ferromagnetic type of ordering.
Электропроводность и барьерные свойства тонких пленок ниобата лития-=SUP=-*-=/SUP=-
Authors: Гудков С.И. , Бакланова К.Д. , Каменщиков М.В. , Солнышкин А.В. , Белов А.Н.
Published: March 2018

AbstractThe thin-film structures made of LiNbO_3 and obtained via laser ablation and magnetron sputtering are studied with volt-farad and volt-ampere characteristics. A potential barrier on the Si–LiNbO_3 interface was found for both types of the films with the capacitance-voltage characteristics. The current-voltage characteristics showed that there are several conduction mechanisms in the structures studied. The Poole–Frenkel effect and the currents limited by a space charge mainly contribute to the electrical conductivity in the LiNbO_3 film produced with the laser ablation method. The currents limited by a space charge contribute to the main mechanism in the film heterostructure obtained with the magnetron sputtering method.
Влияние температуры спекания на формирование сегнетоэлектрических свойств керамики цирконата-титаната свинца
Authors: Барабанова Е.В. , Топчиев А.А. , Малышкина О.В.
Published: March 2018

AbstractEffect of the sintering temperature on the formation of the microstructure, the domain structure, and the ferroelectric properties of a lead zirconate–titanate Pb(Ti_ x Zr_1 – x )O_3 piezoelectric ceramics has been studied. It is shown that the ferroelectric phase forms at a sintering temperature of 860°C. At higher sintering temperatures, the main effect on the properties is due to a unit cell deformation and free charge carriers.
Оценки констант электрон-фононной связи графена с металлическими и неметаллическими подложками
Authors: Давыдов С.Ю.
Published: March 2018

AbstractTwo modes of graphene–substrate interaction have been considered: a weak van der Waals bond and a strong covalent bond. The Lennard–Jones potential and Harrison bond-orbital method are used in the former and latter cases, respectively. Analytical expressions for the electron–phonon interaction constants, which contain only two parameters (binding energy E _ B for graphene and a substrate and distance d between them) have been obtained. The constants have been calculated for metallic, semiconductor, and dielectric substrates.
Влияние механического растяжения на адсорбционные свойства легированного азотом графена
Authors: Долинский И.Ю. , Катин К.П. , Гришаков К.С. , Прудковский В.С. , Каргин Н.И. , Маслов М.М.
Published: March 2018

AbstractThis paper presents the results of quantum chemical modeling of chemisorption of atomic hydrogen and epoxy, carboxyl, and hydroxyl functional groups on nitrogen-doped graphene. It is shown that the substitutional nitrogen atom does not bind to adsorbing groups directly, but significantly increases the adsorption activity of neighboring carbon atoms. Mechanical stretching of doped graphene reduces the adsorption energy of all the aforementioned radicals. This reduction is significantly greater for the epoxy group than for the other functional groups. The results obtained confirm that, upon a sufficient stretching of a nitrogen-doped graphene sheet, the dissociation of molecular hydrogen and oxygen with subsequent precipitation of the resulting radicals onto graphene can be energetically favorable.
Дозовая зависимость формирования нанокристаллов в имплантированных гелием слоях кремния
Authors: Ломов А.А. , Мяконьких А.В. , Чесноков Ю.М. , Денисов В.В. , Кириченко А.Н. , Денисов В.Н.
Published: March 2018

AbstractThe possibility of nanocrystal formation in silicon layers subjected to plasma-immersion helium-ion implantation at an energy of 5 keV has been proved for the first time. The effect of the implantation dose on the microstructure of the layers has been studied by X-ray reflectometry, transmission electron microscopy and Raman scattering. It has been established that the formation of silicon nanocrystals with dimensions of 10–20 nm is accompanied by a pronounced dependence on the ion flux and occurs at a dose of 5 × 10^17 cm^–2 with subsequent annealing at 700–800°C. The excessive dose has been shown to cause the destruction of the upper protective sublayer and the degradation of the optical properties of nanocrystals.
Исследование метода оптимизации формы тела для уменьшения силы аэродинамического сопротивления в потоке газа
Authors: Чернов Н.Н. , Палий А.В. , Саенко А.В. , Маевский А.М.
Published: March 2018

AbstractAerodynamic flow past bodies of various geometrical shapes was studied, and the aerodynamic drag force was reduced through optimization of the body shape using a specially proposed method. The resulting drag force was compared to that for bodies formed by revolution of the profiles of well-known standard series. The study was performed using the Ansys Fluent software for isothermal laminar steady-state flows of incompressible fluid with constant density in a velocity range of 0–10 m/s. It is shown that the aerodynamic drag force for a body with the optimized shape is lower than analogous values for the bodies of revolution with Su-26 and NASA-0006 reference profiles. In comparison to the aerodynamic-drag-force level of 100% for the body of revolution with NASA-0006 profile, the drag force for Su-26 profile at airflow velocity of 10 m/s is 89.4%, while that for the proposed optimized body shape is 89.2%.
PEMANFAATAN GAMBUT RAWA PENING SEBAGAI PUPUK ORGANIK BRIKET DAN PENGARUHNYA TERHADAP PERTUMBUHAN BATANG BAWAH TANAMAN KARET
Authors: Putra Riko Cahya , Widyasari Titik
Published: March 2018

Pemupukan merupakan faktor penting dalam kegiatan pembibitan tanaman karet. Salah satu cara untuk meningkatan efektivitas pemupukan anorganik adalah dengan pemberian pupuk organik. Salah satu sumber pupuk organik yang cukup besar adalah endapan gambut dari Rawa Pening. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian pupuk organik briket Rawa Pening yang dikombinasikan dengan pupuk anorganik tunggal terhadap pertumbuhan batang bawah tanaman karet. Penelitian dilakukan di kebun percobaan Balai Penelitian Getas, Jawa Tengah. Rancangan penelitian menggunakan Rancangan Acak Kelompok Lengkap terdiri atas 6 perlakuan dengan 5 ulangan. Perlakuan tersebut adalah, 1) Kontrol (perlakuan tanpa pupuk), 2) pupuk tunggal N, P, K, 3) pupuk tunggal N, P, K + pupuk organik briket 1 tablet, 4) pupuk tunggal N, P, K + pupuk organik briket 2 tablet, 5) pupuk tunggal N + pupuk organik briket 1 tablet, 6) pupuk tunggal N + pupuk organik briket 2 tablet. Hasil penelitian menunjukkan bahwa perlakuan pupuk tunggal N, P, K atau pupuk tunggal N yang dikombinasikan dengan pupuk organik briket Rawa Pening dapat meningkatkan pertumbuhan tinggi tanaman, diameter batang, dan bobot basah tanaman dibandingkan dengan kontrol dan perlakuan pupuk tunggal N, P, K. Hal tersebut menunjukkan bahwa pemberian pupuk organik gambut rawa pening mampu meningkatkan efektivitas pemupukan anorganik. Perlakuan pupuk tunggal N + 2 tablet pupuk organik briket Rawa Pening menunjukkan efektivitas agronomi relatif (RAE) tertinggi dengan biaya pupuk yang cukup terjangkau yaitu IDR 634/pohon.
A “opção preferencial pelos pobres” como chave hermenêutica da Exortação Apostólica Evangelii Gaudium
Authors: Lourenço Vitor Hugo
Published: March 2018

A opção preferencial pelos pobres é uma das marcas mais singulares da Igreja latino-america. Cunhada a partir do Concílio Vaticano II e tendo seu ápice nas Conferências de nosso Episcopado, especialmente Medellín, ela encontra eco novamente no pontificado de Francisco, que tem se revelado sensível às questões sociais. Partindo deste princípio, o presente artigo busca analisar a opção supracitada como uma chave hermenêutica de sua Exortação Apostólica Evangelii Gaudium. Para este propósito, tem-se como ponto de partida a compreensão da tarefa hermenêutica da teologia, passando pela força do impulso conciliar, o florescimento de uma nova tradição, o conceito de opção pelos pobres e contra a pobreza, culminando nas reflexões de Francisco a partir de sua exortação e nos seus desdobramentos para a vida da Igreja como um todo.
Páscoa ou páscoas judaicas?
Authors: De Araujo Gilvan Leite
Published: March 2018

A celebração da Páscoa em Israel relembra o evento histórico no qual os hebreus, escravos do Egito, foram libertados pelas mãos forte de Iahweh e conduzidos para a Terra Prometida. Apesar da prescrição de uma memória a ser celebrada perpetuamente, nota-se que nem sempre foi observado tal prescrição e os motivos e ritos sofreram mudanças substanciais no decorrer da história de Israel conforme se observa nos relatos sobre a Páscoa nos livros sagrados do Antigo Testamento.
In persona Christi servi: sobre a diaconia de Cristo e o ministério diaconal
Authors: Pinto Luciano Rocha
Published: March 2018

Inácio de Antioquia foi, possivelmente, o primeiro a aproximar e relacionar o ministério dos diáconos a Jesus Cristo ao afirmar que devem ser respeitados como o próprio Cristo. O exercício eclesial da diaconia forjou, assim, o diácono, conformando-o ao Cristo Servo. Essa aproximação ganha visibilidade, nas primeiras comunidades, a partir das exigências qualitativas daqueles ministros. Como o Cristo Servo, devem os diáconos serem mansos e verazes, reconhecidos por seu zelo à Boa Nova e seu cuidado para com o próximo. A diaconia de todo cristão deve, portanto, ser o sinal distintivo do diácono, cujo ministério está ordenado ao serviço.
A ratio studiorum jesuítica no espírito do trivium
Authors: Alves Murilo
Published: March 2018

A Contrarreforma católica, decorrente do confronto com a Reforma protestante, elabora, no âmbito da Ordem jesuítica, a pedagogia da Ratio Studiorum que, inspirada no espírito do Trivium escolástico, vai remontar ao humanismo dos clássicos greco-latinos, para desvitalizá-los e instrumentalizá-los a serviço de uma Retórica “cristianizada”, com o propósito de um redressement da práxis católica no contexto da Cristandade ameaçada.
A Ceia do Senhor na Comunidade Cristã: testemunhos bíblicos
Authors: De Freitas Manoel Pacheco
Published: March 2018

A Ceia do Senhor na Comunidade Cristã – testemunhos bíblicos. Este estudo se concentra sobre os problemas das questões das fontes e da estratificação dos textos relacionados à Ceia do Senhor, cujo objetivo principal é aprofundar a fé da Igreja.
As estruturas retóricas paulinas em traduções em português: um estudo de 1 Coríntios 1,17-25
Authors: Artuso Vicente , Casagrande Vera Lúcia Membrive , Catenassi Fabrizio Zandonadi
Published: March 2018

O objetivo deste trabalho foi conduzir uma análise estilístico-literária de 1Cor 1,17-25, focalizando os elementos retóricos e orais desse discurso paulino, bem como investigar a forma com que algumas versões da Bíblia em português interpretam esses elementos. Apresentou-se a tradução e uma análise linguístico-sintática de 1Cor 1,17-25, o contexto literário e a delimitação do texto. Então, realizou-se a análise estilístico literária. Paulo era conhecedor da retórica grega ao usar a diatribe, a linguagem da controvérsia e ao jogar com perguntas retóricas para tornar o discurso mais convincente. Nesse artigo, observou-se que, para algumas traduções, em certos detalhes, a retórica de Paulo é um tanto atenuada quanto a interpretações de determinados termos, especialmente, quando a conjunção pode ter valor adversativo e isso não é considerado.
A comunicação do sagrado na liturgia
Authors: Brustolin Leomar Antônio , Gomes Tiago De Fraga
Published: March 2018

O horizonte litúrgico é a ação econômica de Deus na história. A imanência dos gestos simbólicos visa intermediar a transcendência significativa do sagrado celebrado na ação litúrgica. A densidade mística da Igreja emerge da graça divina e ajuda a superar as tentações do juridicismo doutrinal e institucional e do rubricismo normativo e estético. Com Romano Guardini pretende-se aprofundar o espírito da liturgia a partir do questionamento sobre o que está vivo hoje, e que é capaz de fazer o crente experimentar o mistério na celebração. Para isso, o indivíduo e a comunidade precisam ser educados e formados para compreender em que consiste a essência da ação litúrgica. O ser humano inteiro é sujeito da atividade litúrgica. Uma liturgia simbólica, encarnada, orante e meditativa é um ideal a ser buscado a fim de que a comunicação do sagrado se efetive na liturgia.
Águia ou abutre? (Ex 19,4)
Authors: Grenzer Matthias , Brey Petterson
Published: March 2018

As primeiras palavras que o Senhor, Deus de Israel, dirige, no monte Sinai, a seu povo por meio de Moisés envolvem uma imagem ou metáfora. Deus afirma “ter carregado” seu povo “sobre as asas” de uma determinada espécie de pássaro, “trazendo-o”, dessa forma, “a si mesmo” (Ex 19,4). A maioria das traduções da Bíblia transmite a palavra hebraica em questão – nəšārim, plural de nešer – como “águias”. Contudo, tal opção parece ser o resultado de reflexões hodiernas sobre valores estéticos e/ou morais, sem reconhecer, de modo suficiente, o contexto histórico-cultural do mundo narrado. Em vista disso, o estudo aqui apresentado se propõe a revisitar as vinte e seis ocorrências de nešer na Bíblia Hebraica e algumas imagens pertencentes às culturas do Egito e do Antigo Oriente Próximo, sendo que tais estudos iconográficos se tornam um auxílio importante para a exegese bíblica.