bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil aggregation and organic carbon of Oxisols under coffee in agroforestry systems
Authors: Guimarães Gabriel Pinto , Mendonça Eduardo de Sá , Passos Renato Ribeiro , Andrade Felipe Vaz
Published: April 2014

Intensive land use can lead to a loss of soil physical quality with negative impacts on soil aggregates, resistance to root penetration, porosity, and bulk density. Organic and agroforestry management systems can represent sustainable, well-balanced alternatives in the agroecosystem for promoting a greater input of organic matter than the conventional system. Based on the hypothesis that an increased input of organic matter improves soil physical quality, this study aimed to evaluate the impact of coffee production systems on soil physical properties in two Red-Yellow Oxisols (Latossolos Vermelho-Amarelos) in the region of Caparaó, Espirito Santo, Brazil. On Farm 1, we evaluated the following systems: primary forest (Pf1), organic coffee (Org1) and conventional coffee (Con1). On Farm 2, we evaluated: secondary forest (Sf2), organic coffee intercropped with inga (Org/In2), organic coffee intercropped with leucaena and inga (Org/In/Le2), organic coffee intercropped with cedar (Org/Ced2) and unshaded conventional coffee (Con2). Soil samples were collected under the tree canopy from the 0-10, 10-20 and 20-40 cm soil layers. Under organic and agroforestry coffee management, soil aggregation was higher than under conventional coffee. In the agroforestry system, the degree of soil flocculation was 24 % higher, soil moisture was 80 % higher, and soil resistance to penetration was lower than in soil under conventional coffee management. The macroaggregates in the organic systems, Org/In2, Org/In/Le2, and Org/Ced2 contained, on average, 29.1, 40.1 and 34.7 g kg-1 organic carbon, respectively. These levels are higher than those found in the unshaded conventional system (Con2), with 20.2 g kg-1.
Perennial grasses for recovery of the aggregation capacity of a reconstructed soil in a coal mining area in southern Brazil
Authors: Stumpf Lizete , Pauletto Eloy Antonio , Fernandes Flavia Fontana , Suzuki Luis Eduardo Akiyoshi Sanches , Silva Tiago Stumpf da , Pinto Luiz Fernando Spinelli , Lima Claudia Liane Rodrigues de
Published: April 2014

The construction of a soil after surface coal mining involves heavy machinery traffic during the topographic regeneration of the area, resulting in compaction of the relocated soil layers. This leads to problems with water infiltration and redistribution along the new profile, causing water erosion and consequently hampering the revegetation of the reconstructed soil. The planting of species useful in the process of soil decompaction is a promising strategy for the recovery of the soil structural quality. This study investigated the influence of different perennial grasses on the recovery of reconstructed soil aggregation in a coal mining area of the Companhia Riograndense de Mineração, located in Candiota-RS, which were planted in September/October 2007. The treatments consisted of planting: T1- Cynodon dactylon cv vaquero; T2 - Urochloa brizantha; T3 - Panicum maximun; T4 - Urochloa humidicola; T5 - Hemarthria altissima; T6 - Cynodon dactylon cv tifton 85. Bare reconstructed soil, adjacent to the experimental area, was used as control treatment (T7) and natural soil adjacent to the mining area covered with native vegetation was used as reference area (T8). Disturbed and undisturbed soil samples were collected in October/2009 (layers 0.00-0.05 and 0.10-0.15 m) to determine the percentage of macro- and microaggregates, mean weight diameter (MWD) of aggregates, organic matter content, bulk density, and macro- and microporosity. The lower values of macroaggregates and MWD in the surface than in the subsurface layer of the reconstructed soil resulted from the high degree of compaction caused by the traffic of heavy machinery on the clay material. After 24 months, all experimental grass treatments showed improvements in soil aggregation compared to the bare reconstructed soil (control), mainly in the 0.00-0.05 m layer, particularly in the two Urochloa treatments (T2 and T4) and Hemarthria altissima (T5). However, the great differences between the treatments with grasses and natural soil (reference) indicate that the recovery of the pre-mining soil structure could take decades.
A respeito da questão da democracia no marxismo (a polêmica entre Althusser e Poulantzas)
Authors: Motta Luiz Eduardo
Published: April 2014

A problemática da democracia não é estranha, nem alheia ao pensamento marxista. Contrariamente a isso, a democracia foi uma das principais questões debatidas no início do século XX pelo marxismo da II Internacional como também nos anos 1970 com a emergência do "eurocomunismo". Nesse último contexto o debate ficou marcado pelas intervenções de Louis Althusser e Nicos Poulantzas sobre o conceito de ditadura do proletariado e o de socialismo democrático, nas quais demarcavam ainda qual a estratégia que deveria ser adotada pelos partidos e movimentos de esquerda. O pano de fundo desse debate entre os pensadores estabeleceu uma rica análise sobre o significado do conceito de democracia no pensamento marxista, que demarca as suas diferenças em relação ao pensamento político moderno na sua definição de Estado e de democracia.
Desafios ativistas à democracia deliberativa
Authors: Young Iris Marion
Published: April 2014

Neste artigo, Iris Young discute o papel dos protestos e da ação direta na democracia. Sua estratégia para avaliar os argumentos a favor e contra a ação direta é o diálogo hipotético entre duas personagens, uma ativista e uma democrata deliberativa. Considerando como ambas lidam com os conflitos e desigualdades nas democracias e como definem a boa cidadania, ela discute os limites e potenciais dessas abordagens teóricas e práticas. Revelando conflitos que não podem ser ultrapassados e possíveis continuidades entre elas, a autora destaca que os protestos são tão necessários às democracias quanto o diálogo e a persuasão. Faz, assim, a crítica ao potencial paralisante da democracia deliberativa, em sua busca por consensos amplos.
Gestão de relacionamento com fornecedores em arranjos produtivos locais: o caso do Vale da Eletrônica
Authors: Murad Ronan de Brito , Lima Renato da Silva , Sacomano Neto Mário
Published: April 2014

Este artigo analisa a gestão dos relacionamentos com fornecedores, por meio do método de Olsen & Ellram, em cinco empresas tecnológicas de pequeno e médio porte situadas no arranjo produtivo local (APL) do Vale da Eletrônica em Santa Rita do Sapucaí, MG. O estudo tem caráter exploratório, descritivo e a coleta de dados foi realizada in loco através de entrevistas com executivos dessas cinco empresas. Conclui-se que existe uma elevada necessidade de as empresas firmarem parcerias tecnológicas junto aos fornecedores devido à possibilidade do aumento de competitividade atrelada à tecnologia. Entretanto, os relacionamentos com fornecedores ainda são incipientes e informais, sem o suporte de estratégias e sistemas de integração. Devido à utilização de insumos de alta tecnologia, a integração com os fornecedores tem elevado potencial de melhorar a competitividade das empresas. Entretanto, para fomentar esse potencial, o APL e suas instituições necessitam desenvolver políticas de incentivo e ações conjuntas.
Nutritional balance and yield for green manure orange trees
Authors: Ragozo Carlos Renato Alves , Leonel Sarita , Tecchio Marco Antonio
Published: April 2014

Intercropping could efficiently prevent soil nutrient losses caused by extensive agriculture. The present study aimed to assess the effect of green manure on the nutritional status of orange trees cultivar 'Pera' (Citrus sinensis (L.) Osbeck). The plants were grafted on 'Cravo' lime trees and were then planted in a 7x4m space. Four different treatments corresponding to the evaluated green manures were employed: jack bean (JB) (Canavalia ensiformis DC), lablab (LL) (Dolichos lablab L.), pigeon pea (PP) (Cajanus cajan L. Millsp), and Brachiaria (BQ) (Brachiaria brizantha Hochst ex A. Rich. Stapf) as control. The experimental design was in randomized blocks, in split-plot time, with six replicates, with four treatments (green manures) and two plants per evaluation. The nutritional status was assessed by using the DRIS method (Diagnosis and Recommendation Integrated System); the yield and the macro and micronutrient levels contained in green manures and in the control was also determined. The nutritional diagnosis indicated that, in the two years of experiment, plants treated with green manure showed better nutritional balance index compared to Brachiaria. This suggests that, over time, green manure can lead to better nutritional balance. Pigeon pea treatment showed the highest yields, compared to control, in the two evaluated crop cycles (2004/05 and 2005/06).
Scarabaeoidea (Insecta: Coleoptera) no Cerrado brasileiro: estado atual do conhecimento
Authors: Luçardo Milena , Oliveira Charles Martins de , Frizzas Marina Regina
Published: April 2014

Besouros pertencentes à superfamília Scarabaeoidea ocupam habitats variados, possuem hábitos alimentares diversificados, desempenham importante papel ecológico e diversas espécies apresentam importância agrícola. No entanto, estudos com esse grupo na região do Cerrado são escassos. Nesta revisão realizou-se um levantamento dos artigos publicados nos últimos 30 anos a respeito dos Scarabaeoidea no Cerrado. Foram recuperados 64 artigos, realizados em nove unidades da federação, que focavam quatro temas principais: espécies praga, aspectos bioecológicos, biodiversidade e importância ecológica, e técnicas e metodologias de coleta de Scarabaeoidea. Os resultados desta revisão indicam que poucos estudos foram realizados com os Scarabaeoidea no Cerrado brasileiro nas últimas décadas frente à importância e diversidade desse grupo de insetos.
Farelo de crambe nas formas in natura ou reduzida em antinutrientes na dieta do jundiá
Authors: Pretto Alexandra , Silva Leila Picolli da , Radünz Neto João , Nunes Lucas Mesquita da Costa , Freitas Isadora Liberalesso de , Loureiro Bruno Bianchi , Santos Sergio Alves dos
Published: April 2014

Este estudo avaliou os efeitos da substituição parcial de farinha de peixe e farinha de carne e ossos por farelo de crambe, sobre o crescimento, enzimas digestivas e parâmetros bioquímicos no jundiá (Rhamdia quelen). Este coproduto agroindustrial foi incluído na alimentação de jundiás na forma in natura ou reduzido em antinutrientes, obtido após a aplicação de tratamento químico ao farelo. A inclusão desses ingredientes foi comparada ao tratamento controle (proteína baseada em farinhas de origem animal) durante nove semanas. Crescimento semelhante ao controle foi observado em peixes alimentados com farelo de crambe in natura ou tratado quimicamente na dieta. A inclusão do farelo in natura reduziu a atividade de protease ácida e colesterol plasmático, mas não alterou os parâmetros bioquímicos hepáticos. Menor concentração de glicogênio e glicose no fígado e aumento na aspartato aminotransferase foi encontrada nos peixes alimentados com farelo de crambe tratado, sinalizando uma condição de carência energética. A similar resposta no crescimento, aliada às leves alterações digestivas e metabólicas com o farelo de crambe in natura em relação ao farelo tratado, pode indicar que, no nível de inclusão utilizado, este ingrediente não necessita de um processo prévio para redução de antinutrientes.
Desenvolvimento de espessante alimentar com valor nutricional agregado, destinado ao manejo da disfagia
Authors: Pagno Carlos Henrique , Souza Lucéia Fatima , Flores Simone Hickmann , Jong Erna Vogt de
Published: April 2014

A disfagia se caracteriza por uma disfunção no processo de deglutição, sinal prevalente de doenças degenerativas como esclerose múltipla e doença de Parkinson. Alimentos de textura modificada e bebidas espessadas são tradicionalmente utilizados no auxílio para o tratamento clínico da disfagia. Assim, este trabalho objetivou desenvolver uma formulação de espessante alimentar com valor nutricional agregado, e avaliar sua eficiência em diferentes alimentos líquidos (leite integral, sucos de maçã, uva e laranja), sob diferentes condições de tempo de preparo (10 e 120 minutos e 24 horas) e temperatura ambiente (25°C) e refrigerada (10°C). A formulação foi composta de concentrado proteico de soro, mix de vitaminas e minerais e goma guar como agente espessante. Os valores obtidos para a viscosidade mostraram diferença estatisticamente significativa (P<0,05) entre os tempos de espessamento, sendo que as viscosidades no tempo de 10 minutos e após 24 horas variaram, respectivamente, 58±3cP a 180±2cP na consistência de néctar; de 310±4Cp a 1084±3cP na consistência de mel e 844±14 a 2848±22cP na consistência de pudim. No entanto, a maioria das bebidas permaneceu dentro dos padrões internacionais sugeridos pela National Dysphagia Diet (NDD), para a consistência de alimentos destinados a pacientes disfágicos.
Determinação da doçura ideal em néctar de mamão adicionado de açúcar
Authors: Braga Héberly Fernandes , Conti-Silva Ana Carolina
Published: April 2014

O mamão é um fruto cuja polpa possui características sensoriais, químicas e digestivas atrativas, apresentando alta produção no país. Apesar disso, o néctar desse fruto é pouco difundido no mercado. Assim, o presente trabalho objetivou elaborar néctares de mamão com diferentes teores de açúcar, visando a adequar a doçura ideal em açúcar para esse produto. Foram elaboradas quatro formulações de néctar de mamão, com as mesmas proporções de polpa e água, e com concentrações de açúcar a 6, 8, 10 e 12%. Cem julgadores não treinados participaram do teste afetivo de aceitação por meio da escala do ideal com nove categorias, variando de "extremamente menos doce que o ideal" a "extremamente mais doce que o ideal". Houve um aumento no percentual para a categoria "doçura ideal", conforme aumento da concentração de açúcar de 6 para 12%. Foi verificada também uma predominância na frequência de respostas para as categorias "menos doce que o ideal", para o néctar com 6% de açúcar, e para as categorias "mais doce que o ideal", para o néctar com 12% de açúcar. Para a obtenção de um néctar de mamão com "doçura ideal", a concentração de açúcar deve ser de 10,4%.
Ripening and shelf life of 'BRS Caipira' banana fruit stored under room temperature or refrigeration
Authors: Lima Orjana Santos , Souza Elaine Goes , Amorim Edson Perito , Pereira Márcio Eduardo Canto
Published: April 2014

BRS Caipira variety, internationally known as 'Yangambi km 5', is an alternative to meet the demand of 'Maçã'-type fruit due to its resistance to Panama disease. This study had the objective of generating information about 'BRS Caipira' fruit ripening and cold storage potential. For the ripening study fruits were stored under room temperature conditions (25±2°C / 58±6% U.R.) and assessed for postharvest life evaluation and characterization of seven maturity stages based on peel color: completely green - MS1; green with yellow traces - MS2; more green than yellow - MS3; more yellow than green - MS4; yellow with green tips - MS5; completely yellow - MS6; yellow with brown spots - MS7. For the cold storage potential study, fruits at MS1 were cold stored (14±1°C / 53±2% U.R.) for 28 days. Weekly, fruits were transferred to room temperature to ripen until MS6 when were assessed for quality attributes. Ripening of 'BRS Caipira' fruit was characterized as slow between MS1 and MS2 (averaging five days), then fast between MS2 and MS6 (up to four days in average), and undergoing determinant changes between MS6 and MS7: pulp yield reached 80%, titratable acidity reduced by 50% and ratio increased by 78%. Cold storage extended shelf life by up to 19 days as compared with control, without visible symptoms of chilling injury, although tends to reduce soluble solids in ripe fruit. Maximum recommended time for storage of 'BRS Caipira' fruit at 14°C is 21 days, since it allows a few more days under room temperature until fruit reach MS6.
Fruit yield and root system distribution of 'Tommy Atkins' mango under different irrigation regimes
Authors: Santos Marcelo R. dos , Martinez Mauro A. , Donato Sérgio L. R. , Coelho Eugênio F.
Published: April 2014

This study aimed to evaluate the fruit yield and the distribution of 'Tommy Atkins' mango root system under different irrigation regimes in the semiarid region of Bahia. The experimental design was completely randomized with five treatments and three replicates: 1 - Irrigation supplying 100% of ETc in phases I, II and III; 2 - Regulated deficit irrigation (RDI) supplying 50% of ETc in phase I (beginning of flowering to early fruit growth); 3 - RDI supplying 50% ETc in phase II (start of expansion until the beginning of physiological maturity); 4 - RDI supplying 50% ETc in phase III (physiological mature fruits); 5 - No irrigation during all three phases. The regulated deficit irrigation supplying 50% of the ETc during phase I and II provided larger root length density of 'Tommy Atkins' mango. Regardless of management strategy, the roots were developed in all evaluated soil volume and the highest density is concentrated from 0.50 to 1.50 m distance from the trunk and in 0.20 to 0.90 m depth in the soil, that suggests this region to be the best place for fertilizer application as well for soil water sensor placement. The application of RDI during fruit set does not influence either root distribution or production. Root system and crop production is significantly reduced under no irrigation conditions.
Níveis críticos para atributos do solo pela distribuição normal reduzida em culturas anuais de subsistência
Authors: Souza Henrique A. de , Cavalcante Ana C. R. , Tonucci Rafael G. , Pompeu Roberto C. F. F. , Souza Maria C. M. R. de , Maia Celsemy E.
Published: April 2014

Objetivou-se, neste trabalho, propor níveis críticos para atributos químicos do solo utilizando-se a distribuição normal reduzida em áreas de agricultura familiar de subsistência cultivadas com milho e feijão-caupi, no semiárido brasileiro. Amostras de solo foram coletadas em propriedades de agricultores familiares do Sertão dos Inhamuns-Crateús. Para a obtenção de níveis críticos foi utilizada a distribuição normal reduzida que utiliza os dados de produtividade e a relação entre produtividade e o atributo químico do solo atribuindo o nível crítico para 90% da produtividade máxima. Os níveis críticos obtidos para as áreas cultivadas com milho e feijão caupi em região semiárida são: MO (g kg-1): 7,3 e 7,5; pH: 6,6 e 6,5; P (mg dm-3): 8,6 e 8,2; K: 2,8 e 2,7; Ca (mmol c dm-3): 33,3 e 22,4; Mg (mmol c dm-3): 11,2 e 9,9 e saturação por base (%): 73 e 71, respectivamente. O nível crítico pela distribuição normal reduzida pode ser utilizado com vista à obtenção de níveis críticos para atributos químicos do solo. Os atributos com maior frequência para o índice negativo em relação ao nível crítico estimado (NCRIz) são Ca > V > pH > Mg > K = MO > P e V > pH > P > MO > Mg > K > Ca para as áreas de milho e feijão, respectivamente.
Vibrações mecânicas: um agente estressor no transporte de pintos
Authors: Donofre Ana C. , Silva Iran J. O. da , Nazareno Aérica C.
Published: April 2014

As vibrações mecânicas, presentes no transporte de cargas vivas, podem comprometer a estabilidade fisiológica e o futuro desempenho dos animais de produção. O objetivo desta pesquisa foi avaliar, por meio de simulações, o efeito de dois níveis de aceleração (9,64 e 15,19 m s-2) sobre o estresse e o desempenho de pintos de corte de um dia. As vibrações foram simuladas utilizando-se um agitador mecânico e as intensidades de vibração estudadas por valores de aceleração geral. O período de simulação durou duas horas para cada tratamento e as aves tiveram seus parâmetros (diferença de peso; frequência respiratória e desempenho na primeira semana) comparados a grupos-controle (sem vibração). Realizou-se um delineamento inteiramente casualizado em que os resultados obtidos indicaram que esses níveis não influenciaram significativamente (p < 0,05) na diferença de peso nem no desempenho na primeira semana de vida; entretanto, os pintos submetidos à aceleração de 15,19 m s-2 obtiveram um aumento significativo (p < 0,05) na frequência respiratória (54,33 mov min-1) concluindo-se, assim, que as vibrações podem atuar como potencial estressor no transporte dessas aves.
Soldagem do aço inoxidável AISI 316 com laser à fibra de alta potência: influência dos parâmetros operacionais na micro dureza e na susceptibilidade à corrosão eletrolítica dos cordões de solda
Authors: Coelho Bruno Nazário , Lima Milton Sérgio Fernandes , Costa Adilson Rodrigues da
Published: April 2014

Este trabalho faz uma avaliação da influência de parâmetros operacionais utilizados no processo de soldagem a laser do aço inoxidável AISI 316. Os resultados dos experimentos de soldagem realizados com parâmetros ajustados para diversas situações foram avaliados levando em consideração a densidade de potência disponibilizada e o tempo de interação do feixe com o metal base. Essas avaliações foram baseadas nos resultados de microdureza e nos ensaios de corrosão eletrolítica das soldas, auxiliadas pela macrografia do cordão de solda. Buscou-se evidenciar correlações entre os parâmetros operacionais selecionados para os experimentos e os resultados obtidos nos cordões de solda, medindo-se grandezas como largura e profundidade. Concluiu-se que a escolha adequada dos parâmetros operacionais é fundamental para a garantia da qualidade dos cordões de solda. Além disso, validou-se um método rápido de avaliação da susceptibilidade dos cordões de solda à corrosão.
Fractografía y disipación de energía cinética en un panel balístico de cerámica/polímero sometido al impacto de un proyectil metálico
Authors: Barrera Torres Giovanni , Vélez Restrepo Juan Manuel
Published: April 2014

En este trabajo se exploró el comportamiento y los mecanismos de daño de un panel laminado compuesto a partir de materiales poliméricos y cerámicos, ante el impacto de un proyectil metálico. Se realizó el diseño de un sistema con la cara de impacto en material cerámico (SiC), con respaldo elaborado en polietileno de peso molecular ultra alto (UHMWPE), placas elaboradas con geometría cuadrada de 200 mm de lado y 5 mm de espesor, y cortes de tejido polimérico con iguales dimensiones de área. Se tomó como referencia el montaje de la norma (NIJ) Standard 0101.06 para el ensayo a impacto balístico; en el material cerámico se identificó la formación de cráter, fracturas y delaminación como mecanismos de falla predominantes, utilizando microscopia óptica y de barrido; en el material polimérico se observó fibrilación, torsión, fusión de fibras, delaminación y deformación cónica y posteriormente se analizaron las muestras empleando los modelos de balance de energía cinética de "Morye, Smith y de Retch e Ipson". El resultado evidenció que el arreglo con mayor influencia para disipar energía, es el panel elaborado con doble placa cerámica (SiC) y doble capa de tejido polimérico como respaldo.
Aplicação de um planejamento fatorial para a avaliação das propriedades mecânicas, térmicas, morfológicas e de escoamento de compósitos à base de PEAD e CaCO3
Authors: Silva Ana Lúcia Nazareth da , Bertolino Luiz Carlos , Nasser Rachel Oliveira , Costa Leticia Sousa da , Melo Amanda Alves de , Marquezine Lucas Pereira Sampaio , Silva Antonio Henrique Monteiro da Fonseca Thomé da , Alves Victor Oliveira , Nascimento. C. R.V
Published: April 2014

Atualmente, compósitos à base de polímero/carga mineral têm sido alvo de grande interesse, tanto em indústrias quanto em pesquisas acadêmicas, devido à melhora significativa nas propriedades dos materiais quando comparadas ao polímero virgem. O carbonato de cálcio (CaCO3) é um dos materiais mais abundantes do planeta e tem sido geralmente usado na obtenção de compósitos poliméricos. As propriedades de suas partículas (tamanho, forma e módulo) podem provocar um efeito significativo, especialmente no comportamento mecânico. As misturas PEAD/CaCO3 são amplamente usadas na indústria automotiva. No presente estudo, o efeito da incorporação de CaCO3 nas propriedades mecânicas e de escoamento destas misturas foi avaliado através de um planejamento fatorial simples de dois níveis, do tipo 2n, com n = 3 fatores: teor de carga; tamanho de partícula e velocidade de rotação da rosca. As variáveis de resposta analisadas foram: módulo de Young e resistência ao impacto e índice de fluidez (MFI). Os resultados mostraram que, dentro dos níveis estabelecidos, o fator que apresentou mais impacto nas variáveis de resposta foi o teor de carga mineral.
ILA - ILF - ILE - ILG: quem dá conta?
Authors: Jordão Clarissa Menezes
Published: April 2014

Este texto discute pressupostos e implicações dos termos língua franca, internacional, global, estrangeira e adicional relacionados ao inglês. Abordados a partir da práxis pedagógica do ensino-aprendizagem em escolas públicas no Brasil (GIMENEZ, CALVO & EL KADRI, 2011), e segundo um referencial pós-estruturalista com base no pensamento de Derrida e Foucault sobre texto e discurso, o artigo enfoca principalmente a concepção de língua nessa terminologia. As conotações atribuídas à língua inglesa são analisadas a partir da ocorrência dos termos em documentos oficiais, artigos internacionais recentes e resumos de apresentações num congresso brasileiro de formação de professores; os usos dos termos são contrapostos à noção de inglês como língua estrangeira (ILE), utilizada historicamente em referência ao ensino-aprendizagem desta língua no Brasil.
Pode ser... Poderia ser... O uso de modalizações na escrita acadêmica
Authors: Ninin Maria Otilia Guimarães
Published: April 2014

Objetiva-se, neste artigo, discutir, com base na teoria linguística Sistêmico-Funcional (Halliday, 1985, 1994; Halliday e Matthiessen, 2004); na teoria da Avaliatividade (Martin, 2000; Martin e White, 2005; White, 2003, 2010), mais especificamente no sistema de Engajamento; e na perspectiva de Hengeveld (1988, 1989, 2004) sobre modalidade, discutir o uso, por autores mestrandos e doutorandos em Letras/Linguística, da modalidade realizada pelo verbo "poder" e suas formas derivadas, na construção de estratégias discursivas. Considerou-se um corpus de 40 teses e 40 dissertações produzidas entre 2008 e 2011, coletadas de sites de universidades brasileiras públicas e privadas. Os resultados revelaram ausência de critério na escolha do recurso de modalidade com o modal "poder", indicando responsabilidade ora do autor do texto, ora dos autores por ele citados, deixando, porém, transparecer diferentes significados em função de sua relação com outros elementos do discurso e do contexto.
Revision of the GenusAndinentulus(Protura: Acerentomidae: Berberentulinae), with a Key to South and Central American Acerentomidae Species
Authors: Shrubovych Julia , Schneider Clément , D'haese Cyrille A
Published: April 2014

The species Acerentulus rapoportiCondé, 1963 is redescribed, transferred to genus AndinentulusTuxen, 1984, and synonymized with Andinentulus ebbeiTuxen, 1984 on the basis of type series. Andinentulus rapoporti (Condé, 1963) comb. nov. is characterized by very long and sword-shaped foretarsal sensillum a' sensillum b that is half the length of sensillum c, presence of additional seta d6 on the head, absence of seta P1a on abdominal tergites I–VI, and short oblong accessory setae on tergites I–VI. The differences between the genus Andinentulus and morphologically similar genera, which have three setae on the abdominal legs, are discussed. A key to South and Central American Acerentomidae species and their distribution in America is provided. The mitochondrial cytochrome oxidase subunit I sequence (barcode) is provided for several specimens of the species and compared with other proturan barcodes with a phylogenetic analysis.
Pure creep, maturity and MP-creep in concrete in terms of an exo-process
Authors: Blechman Isaak
Published: April 2014

Pure asymptotic creep of concrete is described as a manifestation of relaxation under low constant stress, where creep-induced damage is absent. An analytical solution for pure creep is obtained as a time-operator and is shown as an exo-function. The potential of stress loss in pure creep is found to be essentially higher than in relaxation due to steady re-elevation of the relaxed stress to the initial constant value. The duration of pure creep is described and found to be prolonged versus relaxation. Elastic maturity (the increase of the elastic modulus with time) and strength maturity (increase in concrete strength with time) are also exo-processes, described by a common time-operator. For structural concrete, they differ in the exponent – for elastic maturity, the exponent is 4·2–4·8 and for strength maturity its value is 3·8–4·2, depending on the type and content of cement. The influence of temperature up to 70°C is incorporated in the exo-operator of maturity. MP-creep – a combination of plain creep and increasing maturity – is described by equations, based on material parameters determined from tests. It is shown that elastic strain decreases under MP-creep.
Ecological and corrosion behavior of depleted uranium
Authors: Stojanovic Mirjana , Lacnjevac Caslav , Mihajlovic Marija , Petrovic Marija , Sostaric Tanja , Petrovic Jelena , Lopicic Zorica
Published: April 2014

Environmental pollution with radionuclides, particularly uranium and its
decay products is a serious global problem. The current scientific studies
estimated that the contamination originating from TENORM, caused by nuclear
and non-nuclear technologies, has significantly increased natural level of
radioactivity in the last thirty years. During the last decades all the more
were talking about the "new pollutant" - depleted uranium (DU), which has
been used in anti-tank penetrators because of its high density, penetration
and pyrophoric properties. It is estimated that during the Gulf War, the war
in Bosnia and Yugoslavia and during the invasion of Iraq, 1.4 million
missiles with depleted uranium was fired. During the NATO aggression against
the ex Yugoslavia in 1999., 112 locations in Kosovo and Metohija, 12
locations in southern Serbia and two locations in Montenegro were bombed. On
this occasion, approximately 10 tons of depleted uranium were entered into
the environment, mainly on land, where the degree of contamination ranged
from 200 Bq / kg to 235 000 Bq/kg, which is up to 1000 times higher than the
natural level. Fourteen years ago there was very little information about
the behavior of ecological systems damaged by DU penetrators fired. Today,
unfortunately, we are increasingly faced with the ?invisible threat" of
depleted uranium, which has a strong radioactive and hemotoxic impact on
human health. Present paper provides a detailed overview of the current
understanding of corrosion and corrosion behavior of DU and environmental
factors that control corrosion, together with indicators of environmental
impact in order to highlight areas that need further attention in developing
remediation programs.
Effects of different cutting methods and times of cutting on growth performance and gum resin production of ferula assa-foetida
Authors: Gholami Barat , Faravani Mahdi
Published: April 2014

Ferula assa-foetida L. is an important industrial and medicinal plant of Iran
which is mainly distributed in arid and semi-arid areas of Khorasan province
in north east of the country. Gum of this plant is widely used in
pharmacological industry. This plant is endangered because of more harvesting
and unsustainable harvesting methods. The objective of this study was to
evaluate the effects of different cutting methods (conventional, cut of crown
part, concave and surface) and times of cutting (5, 10 and 13 times) on gum
yield of this species in its wild habitat in Mazar region in Bajistan. The
treatments were studied under a factorial experiment which was arranged in a
completely randomized design with three replications. Results showed
significant differences among cutting methods and times of harvesting. Yield
of gum was affected by times of harvesting and the highest yield was obtained
in 10 cutting times. The highest and lowest gum yields were obtained in
concave method with 10 cutting times (25.24 g/plant) and superficial method
with 5 cutting times (2.02 g/plant), respectively. Results showed that
conventional cutting method destroys crown buds, which causes death of the
plant. The highest gum yields and the best plant regeneration rates were
obtained by using of concave method with 10 cutting times.
The influence of solar activities an occurrence of the forest fires in South Europe
Authors: Radovanovic Milan , Pavlovic Tomislav , Stanojevic Gorica , Milanovic Misko , Pavlovic Mila , Radivojevic Aleksandar
Published: April 2014

In mid-July 2012, hundreds of fires spread over forest stands in the south of
Europe. Considering available satellite and meteorological data we have tried
to determine a method using analogy, whether these fires were preceded by the
intensified solar activity. The justification of this approach lies in the
belief that it is impossible by direct or indirect activity of man to set
fire at the same time to the sites that are geographically separated. In this
paper we have tried to test the hypothesis claiming that charged particles
coming to us from the Sun may be responsible for the number of forest fires.
Unlike some other situations when the potential explanation could be a sudden
influx of the protons of different energy ranges, in our study, there are
electrons as carriers of the potential explanation. Many previous studies
results have shown that there is statistically significant relationship
between the processes on the Sun and certain movements of air masses in the
atmosphere our planet. The presented results in this paper of the correlation
relationships between the mean hourly flows of electrons and the mean hourly
air temperatures in Belgrade and Rome and the analysis of the synoptic
situation as a function of the suggested model so far, indicate that the
number of fires that were occurring more than a week, from July 15, 2012, in
the south of Europe, were caused by electrons coming from the Sun.
Laser-assisted growth of carbon nanotubes—A review
Authors: van de Burgt Yoeri
Published: April 2014

Laser-assisted chemical vapor deposition (LACVD) is an attractive maskless process for growing locally carbon nanotubes at selected places on substrates that may contain temperature-sensitive components. This review gives a comprehensive overview of the reported research with respect to laser assisted CVD for the growth of carbon nanotubes. The advantages and disadvantages of local growth using laser sources are discussed, with a focus on structural quality and properties, such as length, position and alignment, and process control. The paper is divided into two parts. The first part deals with the influence that the main parameters for nanotube growth—gas, catalyst and thermal energy—have on the growth of carbon nanotubes by laser-assisted synthesis. The second part deals with the attempts and successes to control different aspects of local nanotube growth using a laser-assisted growth method.
Psychometric Properties of an Italian Version of the Experiences in Close Relationships-Revised (ECR-R) Scale
Authors: Busonera Alessandra , Martini Pietro San , Zavattini Giulio Cesare , Santona Alessandra
Published: April 2014

This study examined the psychometric properties of a newly translated Italian version of the Experiences in Close Relationships-Revised (ECR–R) Scale. The sample comprised 1,363 adults (906 women, 456 men, 1 unreported sex; ages 18–64 yr., M=33.4, SD=8.9; 84.4% reported being engaged in a romantic relationship, 9.4% declared being single), all living in Italy and speaking Italian as their first language. Exploratory and confirmatory factor analyses showed the expected bi-factorial (anxiety/avoidance) structure and a close correspondence between factors and scales. Test-retest and internal consistency reliabilities were adequate. Correlations with the Relationship Questionnaire, a categorical measure of attachment, and with the Dyadic Adjustment Scale were consistent with the theoretical relations among the constructs. The findings confirm the transcultural validity of the ECR–R.
Corporal Artistic Training Influences Attention: A Pilot Study
Authors: Ribeiro Mônica Medeiros , Lima Isabela , Malloy-Diniz Leandro , Lage Guilherme , Pimentel Lucia Gouvêa , Teixeira Antônio Lúcio
Published: April 2014

This study assessed the effect of the Body Rhythmics (BRIM) on actors' attentional processes. BRIM is a combination of exercises using numbers and rules that enact musical parameters in the moving body through displacements. Male actors ( N = 22) participated in the study: 7 in the BRIM (Study) group and 15 in the Control group (groups were equivalent on mean Raven's IQ). The Continuous Performance Test (CPT–II) was administered before and after an intensive period of BRIM training. There was no significant difference on the CPT–II before training. Group results for before vs after training showed a significant difference for reaction time for the Study group. There was also a trend to increased errors of commission in the Study group after BRIM training.
A SINGLE-POINT METHOD BASED ON DISTORTION POWER FOR THE DETECTION OF HARMONIC SOURCES IN A POWER SYSTEM
Authors: Stevanović Dejan , Petković Predrag
Published: April 2014

This paper describes a new and efficient method for quantifying and detection of the source of distortion caused by a single customer in a case when many other customers exist in a power grid. It is based on measuring distortion power, a component of apparent power that only exists with a nonlinear load. Different definitions for distortion power calculation are investigated. All these definitions show without doubt that the proposed method is feasible. Moreover, this method allows to develop fair and reliable billing schemes for controlling harmonic pollution. Measurement and simulation results confirm the effectiveness and applicability of the method. The proposed solution is suitable for software/hardware upgrade of existing electronic power-meters.
A SYSTEM FOR PRECISE LASER BEAM ANGULAR STEERING
Authors: Iwasińska-Kowalska Olga
Published: April 2014

A system for precise angular laser beam deflection by using a plane mirror is presented. The mirror was fixed to two supports attached to its edges. This article details the theoretical basis of how this deflector works. The spring deflection of a flat circular metal plate under a uniform axial buckling was used and the mechanical stress was generated by a piezoelectric layer. The characteristics of the deformation of the plate versus the voltage control of the piezoelectrics were examined and the value of the change resolution possible to obtain was estimated. An experimental system is presented and an experiment performed to examine this system. As a result, a resolution of displacement of 10-8 rad and a range of 10-5 rad were obtained.
ROTATION ERROR MODELING AND IDENTIFICATION FOR ROBOT KINEMATIC CALIBRATION BY CIRCLE POINT METHOD
Authors: Santolaria Jorge , Conte Javier , Pueo Marcos , Javierre Carlos
Published: April 2014

Screw axis measurement methods obtain a precise identification of the physical reality of the industrial robots’ geometry. However, these methods are in a clear disadvantage compared to mathematical optimisation processes for kinematical parameters. That’s because mathematical processes obtain kinematical parameters which best reduce the robot errors, despite not necessarily representing the real geometry of the robot. This paper takes the next step at the identification of a robot’s movement from the identification of its real kinematical parameters for the later study of every articulation’s rotation. We then obtain a combination of real kinematic and dynamic parameters which describe the robot’s movement, improving its precision with a physical understanding of the errors.
Plateau-Stein manifolds
Authors: Gromov Misha
Published: April 2014

We study/construct (proper and non-proper) Morse functions f on complete Riemannian manifolds X such that the hypersurfaces f(x) = t for all −∞ < t < +∞ have positive mean curvatures at all non-critical points x ∈ X of f. We show, for instance, that if X admits no such (not necessarily proper) function, then it contains a (possibly, singular) complete (possibly, compact) minimal hypersurface of finite volume.
The subalgebra lattice of a finite algebra
Authors: Pióro Konrad
Published: April 2014

The aim of this paper is to characterize pairs (L, A), where L is a finite lattice and A a finite algebra, such that the subalgebra lattice of A is isomorphic to L. Next, necessary and sufficient conditions are found for pairs of finite algebras (of possibly distinct types) to have isomorphic subalgebra lattices. Both of these characterizations are particularly simple in the case of distributive subalgebra lattices. We do not restrict our attention to total algebras only, but we consider the more general case of partial algebras. Moreover, we use connections between algebras and hypergraphs to solve these problems.
On Quasi-Class A Operators
Authors: Mecheri Salah
Published: April 2014

Let H be a separable infinite dimensional complex Hilbert space, and let B(H) denote the algebra of all bounded linear operators on H. Let A;B be operators in B(H). In this paper we prove that if A is quasi-class A and B* is invertible quasi-class A and AX = XB, for some X ∈ C2 (the class of Hilbert-Schmidt operators on H), then A*X = XB*. We also prove that if A is a quasi-class A operator and f is an analytic function on a neighborhood of the spectrum of A, then f(A) satisfies generalized Weyl's theorem. Other related results are also given.
Algorithm for the Calculation of the Two Variables Cubic Spline Function
Authors: Lixandru Ion
Published: April 2014

When having just one variable, the existence and uniqueness of the interpolation spline function reduces to studying the solutions of an algebrical system of equations. This allows us to find a practical way of calculating the interpolation spline function. Also in the case of two variables spline functions, we can construct a linear system of equations determined by the continuity conditions of the spline function and of its partial derivatives on the edge of each division rectangle. The existence and uniqueness of the solution of the obtained system ensure the existence and uniqueness of the two variables interpolation spline function and offers a practical calculation method.

This can be used to determine approximate global solutions, of some partial differential equations, solutions whose values can be determined at any point of their domain of definition and can provide information on derivatives approximate of solutions. After calculating the two variable cubic spline function, we must assess the rest of the approximation.
Strongly Transitive Geometric Spaces Associated with (m, n)-Ary Hypermodules
Authors: Anvariyeh S.M. , Davvaz B.
Published: April 2014

In this paper, we define the strongly compatible relation ϵ on the (m, n)- ary hypermodule M, so that the quotient (M/ϵ*, h/ϵ*) is an (m, n)-ary module over the fundamental (m, n)-ary ring (R/Γ∗, f/Γ∗, g/Γ∗). Also, we determine a family P(M) of subsets of an (m, n)-ary hypermodule M and we give a sufficient condition such that the geometric space (M, P(M)) is strongly transitive.
Effect of the Weld Joint Configuration on Stressed Components, Residual Stresses and Mechanical Properties
Authors: Çevik Bekir , Özer Alpay , Özçatalbaş Yusuf
Published: April 2014

The effect of the weld joint configuration on components has been studied, which are under service loads, under repair or construction and the residual stresses as well as the mechanical properties of the joint have been determined. For this purpose, a horizontal positioned tensile testing device and a semi-automatic MIG welding machine have been used and then the weld joints of the plates were subjected to different elastic stresses. When the temperature of the joined elements decreased to room temperature, applied elastic stresses were released. By this means, the effects of the existing tensile stresses in the joined parts and the tensile stresses created by the welding processes were investigated. The tensile stresses occurring in the joined elements were determined by using the photo-elasticity analysis method and the hole-drilling method. Also, tensile-shear tests were applied in order to determine the effect of permanent tensile loads on the mechanical properties of the joint. Experimental results showed that the application of corner welded lap joints for components under tensile loading significantly decrease the shear strength and yielding capacities of the joint.
The Effects of Austempering Temperature and Time on the Machinability of Vermicular Graphite Iron
Authors: Mavi Ahmet , Korkut Ihsan
Published: April 2014

In this study, the effect of austempering heat treatment on the cutting forces and surface roughness was investigated during the processing of vermicular graphite cast irons (VGCI) which are widely used in the automotive industry due to their high strength properties. The samples were austenitized at 900 °C for 90 minutes and then austempered at different temperatures (320 °C and 370 °C) for 60 min, 90 min, and 120 min. Machinability tests were carried out under dry conditions at the CNC machining center with the cutting parameters selected in accordance with ISO 3685. As a result of processing of austempered vermicular graphite cast irons with different characteristics the formed cutting forces, surface roughness, cylindricity, and circularity were measured and compared. At the end of the tests, it turned out that the ausferrite morphology (fine or coarse structure) can to be controlled with the austempering heat treatment as well as cutting forces and surface roughness were optimized, respectively. The best surface roughness value was obtained for the austempering parameters of 370 °C and 120 minutes.
Plasma Arc Welding of AISI316Ti (EN 1.4571) Stainless Steel: Mechanical, Microstructural, Corrosion Aspects
Authors: Taban Emel , Kaluc Erdinc
Published: April 2014

AISI316Ti (EN1.4571) austenitic stainless steel plates with a thickness of 7 mm were welded by plasma arc welding (PAW) process. Joints were obtained using 316L type of filler metal as well as without filler metal called as Weld 1 and Weld 2, respectively. Tensile and bend testing of the joints were carried out. Impact toughness tests carried out at temperatures from 20 °C down to −60 °C have shown encouraging results. Chemical analysis of the weld deposits were made by glow discharge optical emission spectrometry (GDOES). Photomacrographs and photomicrographs of the cross-sections were used to determine ferrite content and hardness. Intergranular corrosion tests in accordance with TSEN 3157/ENISO 3651-2 were carried out. No corrosion sign was reported. The effect of the consumable has the most influence on the toughness properties. Promising mechanical, toughness and corrosion results are useful, considering the implementation of an innovative process, thus PAW of 316Ti stainless steel.