bluuebunny/crossref_metadata_2025 huggingface dataset:
Processamento hidrotérmico em escala industrial sobre parâmetros de qualidade em frações de aveia
Authors: Klajn Vera Maria , Colussi Rosana , Fiorentini Ângela Maria , Elias Moacir Cardoso , Gutkoski Luiz Carlos
Published: April 2014

A aveia destaca-se dentre os cereais por seu teor e qualidade proteica, alta porcentagem de lipídios distribuídos por todo o grão e predominância de ácidos graxos insaturados, além de possuir altos teores de fibra alimentar, minerais e antioxidantes, responsáveis pelos efeitos benéficos à saúde humana. Devido aos seus constituintes, a aveia apresenta forte tendência à rancidez e, por esse motivo, faz-se necessária a inativação enzimática das cariopses. Na indústria, a inativação normalmente é realizada pelo tratamento hidrotérmico. Objetivou-se, com este trabalho, estudar os efeitos do processamento hidrotérmico em escala industrial sobre parâmetros de composição química, atividade enzimática, β-glicanas e compostos fenólicos solúveis totais nas frações de aveia farinha, farelo e integral. O processamento industrial da aveia foi realizado em batelada com temperatura e pressão constantes e tempo de retenção na coluna de 37min e 110min. O experimento foi conduzido em delineamento inteiramente casualizado, sendo os resultados submetidos à análise de variância e as médias comparadas pelo teste Tukey a 5% de significância. Os constituintes químicos das frações farinha, farelo e integral foram pouco afetados nos tempos de retenção estudados. O tempo de retenção de 37min se mostra mais adequado por ser suficiente para inativar as enzimas lipase e peroxidase e preservar os compostos fenólicos solúveis totais em todas as frações de aveia estudadas.
Caracterização e localização das empresas de serviços tecnológicos intensivos em conhecimento no Brasil
Authors: Guimarães José Geraldo de Araújo , Meirelles Dimária Silva e
Published: April 2014

Um grupo específico de serviços intensivos em conhecimento denominados internacionalmente KIBS - Knowledge Intensive Business Services vem ganhando destaque nos estudos de serviços, posto que são considerados fundamentais para o fomento do desenvolvimento, tanto das empresas, como de regiões e países. Estudos específicos de aglomerações de KIBS sinalizam uma concentração dessas atividades nas regiões metropolitanas, mas no caso brasileiro não há, até o momento, um mapeamento sistemático em nível nacional. O objetivo desta pesquisa foi identificar aglomerações de um típico específico de KIBS, os Technological Knowledge Intensive Business Services (T-KIBS). Na identificação das aglomerações foram calculados os Quocientes de Localização (QL) de cada município e, por meio de um software de georreferenciamento, foi apresentado um mapa consolidado das aglomerações encontradas. Observou-se uma alta concentração geográfica desses serviços em regiões mais desenvolvidas do país, confirmando a característica dessas atividades, que é o uso intensivo do conhecimento e da tecnologia. Ao mesmo tempo, verificou-se uma alta dispersão dos valores de QLs encontrados, confirmando as diferenças das atividades de serviço em relação ao tipo de mercado e à natureza do processo produtivo.
Reforma sanitária e a criação do Sistema Único de Saúde: notas sobre contextos e autores
Authors: Paiva Carlos Henrique Assunção , Teixeira Luiz Antonio
Published: April 2014

No contexto de retorno ao estado democrático, a nova carta constitucional, promulgada em 1988, transformou a saúde em direito individual e deu origem ao processo de criação de um sistema público, universal e descentralizado de saúde, alterando profundamente a organização da saúde pública no país. Os principais aspectos institucionais, políticos e sociais que conformaram a reforma sanitária, suas rupturas, continuidades e principais iniciativas são discutidos neste artigo, tendo por base a literatura produzida pelos autores mais lidos nesse campo de estudos. Sem a pretensão de elaborar uma análise exaustiva, discutimos como a historiografia criada por autores que também foram atores desse mesmo processo avalia as principais características, o processo de surgimento e o legado da reforma sanitária brasileira.
História da reforma sanitária brasileira e do Sistema Único de Saúde: mudanças, continuidades e a agenda atual
Authors: Menicucci Telma Maria Gonçalves
Published: April 2014

A conferência apresenta uma retrospectiva histórica do Sistema Único de Saúde, seus antecedentes e seu legado na configuração atual, e parte da explicação de alguns de seus problemas estruturais, particularmente a convivência de um sistema público e outro privado. Busca identificar problemas que afetam sua completa consolidação, ao mesmo tempo em que chama a atenção sobre o significado profundo da implantação de um sistema único e universal em um país das dimensões do Brasil. Apontam-se os efeitos do próprio Sistema, visto como uma grande transformação no campo dos direitos sociais, introduzindo novos atores no ramo da saúde e introjetando a saúde como direito. Por fim, apresentam-se desdobramentos recentes dessa história que fazem com que o Sistema esteja na agenda pública.
Ernst Hasenclever em Gongo-Soco: exploração inglesa nas minas de ouro em Minas Gerais no século XIX
Authors: Alves Débora Bendocchi
Published: April 2014

A partir do relato de Ernst Hasenclever sobre sua visita à mina de ouro de Gongo-Soco em 1839, o artigo procura compreender o sistema organizacional administrativo e de trabalho implementado pelas empresas inglesas de mineração de ouro em Minas Gerais, sobretudo na segunda metade do século XIX, período no qual o sistema escravista caminhava para seu final. Nosso objetivo é mostrar a continuidade do sistema administrativo e do uso da mão de obra escrava pelas empresas de capital inglês a partir da década de 1830 até o final do século, apesar da pressão exercida pela Inglaterra contra o tráfico transatlântico de escravos e da proibição aos súditos de sua majestade de possuir escravos em qualquer parte do mundo.
Ringue ou academia? A emergência dos estilos modernos da capoeira e seu contexto global
Authors: Assunção Matthias Röhrig
Published: April 2014

A emergência dos estilos modernos de capoeira deve ser considerada no contexto global da modernização de artes marciais em curso na Europa e na Ásia, por um lado, e, por outro, da nova fase da modernidade negra. O confronto, no ringue, da capoeira com o jiu-jítsu e outras lutas levou mestre Bimba a desenvolver sua luta regional baiana. A revitalização da capoeira tradicional como capoeira de Angola, liderada por mestre Pastinha, insere-se no movimento mais amplo de afirmação da cultura afro-baiana em Salvador e da crescente visibilidade do corpo negro no mundo atlântico.
Migrantes na periferia: indígenas, europeus e japoneses no Paraná durante as primeiras décadas do século XX
Authors: Prutsch Ursula
Published: April 2014

Analisa os processos de transformação cultural no Brasil realizados por imigrantes europeus e japoneses, que trouxeram padrões culturais e identidades distintas e se transformaram pela interação com a(s) cultura(s) da sociedade receptora. Tomando como exemplo o estado do Paraná, o artigo oferece um mosaico de culturas em transição por meio do estudo de micro-histórias. Aborda o enfrentamento entre austro-poloneses e austro-ucranianos com os índios botocudos; o discurso de Alberto Frič sobre as perseguições bugreiras no 16o Congresso Internacional de Americanistas em Viena; a colonização no norte do Paraná por europeus; a imigração japonesa como um elemento do “outro exótico”, assim como os conflitos políticos na colônia pluriétnica de Rolândia.
Evaluation of weathering of basaltic lithotypes based on pH, electrical conductivity, and point-load strength tests
Authors: Oliveira Patricia Casarotto de , Zuquette Lázaro Valentin
Published: April 2014

This paper presents the results of an evaluation of the weathering of different basaltic lithotypes (dense basalts, vesicular-amygdaloidal basalts, and basaltic breccias) from four basaltic flows of the Serra Geral Formation of the Itaipu Dam region. Samples were classified according to their degree of weathering based on analysis with a 200X digital microscope and were subjected to pH, electrical conductivity, and point-load strength tests. The results show that pH and electrical conductivity values are effective for the evaluation of weathering, especially when tactile-visual classification does not provide an accurate evaluation of the rock's different degrees of weathering.
Quantificação mineralógica de bauxita boehmítica por difração de raios X
Authors: Soares Guilherme Augusto Batista , Costa Geraldo Magela da , Avelar Angela Nair
Published: April 2014

A quantificação de boehmita em bauxita é de fundamental importância para a determinação da temperatura de digestão no processo Bayer, mas não existe, na literatura, nenhum método rápido e confiável, para se realizar essa determinação. Portanto, nesse trabalho, utilizou-se a difração de raios X, para se realizar a quantificação de boehmita, gibbsita, hematita e goethita em bauxita. Uma amostra de bauxita, oriunda de Gana e contendo 45% de gibbsita e 43% de boehmita, foi submetida a uma lixiviação cáustica a 160ºC, para a remoção da gibbsita. O resíduo da lixiviação, completamente isento de gibbsita, foi tratado com o sistema ditionito-citrato-bicarbonato, para a remoção dos oxi-hidróxidos de ferro, resultando em uma amostra contendo cerca de 85%-89% de boehmita e 9% de TiO2. Curvas de calibração correlacionando as intensidades dos picos de difração com os teores das fases mineralógicas foram obtidas, para padrões preparados pela mistura de quantidades conhecidas de gibbsita, hematita e goethita com a amostra purificada de bauxita. Correlações significativas foram obtidas para os planos cristalográficos (020), (051), (002) e (251) da boehmita; (110), (200), (11-2) e (024) da gibbsita; (012), (024) e (110) da hematita; e (110) e (021) da goethita. Essas correlações podem ser utilizadas, para se quantificar o teor dessas fases em amostras semelhantes de bauxita.
Particle disintegration of an important Brazilian manganese lump ore
Authors: Faria Geraldo Lúcio , Jannotti Nelson , Araújo Fernando Gabriel da Silva
Published: April 2014

The manganese lump ore from Morro da Mina mine is typically silicate carbonated and presents a great economic potential for the ferroalloy companies installed in Minas Gerais. However, its low manganese content, associated with the lack of knowledge about its metallurgical properties makes it difficult for large scale application. This pioneering study aimed to amply investigate this lump ore's particle disintegration. One ton of ore from the mine was homogenized and quartered. Representative samples were characterized by different techniques, such as ICP-AES, XRD, SEM, BET and OM. Aiming to characterize particle disintegration, three parameters were proposed: Cold Disintegration Index (CDI), Decrepitation Index (DI) and Heating Disintegration Index (HDI). By using these indexes, it was possible to conclude that this manganese lump ore did not present significant disintegration at room temperature. At medium temperature test, slight decrepitation occurred, and at high temperatures, intense disintegration was detected. The carbonate decomposition and porosity growth were the main responsible factors for the ore hot particle disintegration.
A study of isochronal austenitization kinetics in a low carbon steel
Authors: Lopes Maximiano Maicon Batista , Cota André Barros
Published: April 2014

The austenite formation under isochronal conditions in Nb microalloyed low carbon steel was studied by means of dilatometric analysis and the data was adjusted to the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation, for different heating rates and for three initial microstructures. It was shown that the kinetics of austenitization of a pearlite+ferrite structure is faster than that of martensite (tempered martensite) at a heating rate of 0.1ºC/s. For heating rates higher than 0.1ºC/s, the kinetics of austenitization of a martensite structure is faster than of pearlite+ferrite one. The K parameter of the JMAK equation increases with the heating rate for the three previous microstructures and it is greater for the initial microstructure composed of ferrite+pearlite. At lower heating rates, the formation of austenite in this steel is controlled by carbon diffusion, independently of the initial microstructure. At higher heating rates, the formation of austenite from an initial microstructure composed of pearlite and ferrite is controlled by interface-controlled transformation.
Organic matter removal from oil-water emulsions by electrocoagulation: 2 - mathematical model
Authors: Rangel Rodolfo Maia , Carvalho Roberto José de , Torem Maurício Leonardo
Published: April 2014

A mathematical model of the organic matter (chemical oxygen demand - COD) removal from synthetic oil-water emulsions by the electrocoagulation process was developed to evaluate the COD abatement. The model comprises the three fundaments of electrocoagulation: electrochemistry, coagulation and flotation. By comparing the experimental and calculated values of COD, it was found that the model was able to adequately predict the concentrations of organic matter (COD) present in the emulsions and satisfactorily describe the electrocoagulation process.
Comparative study of the main flotation frothers using a new HYDROMESS adapted technique
Authors: Veras Moacir Medeiros , Baltar Carlos Adolpho Magalhães , Paulo João Bosco de Araújo , Leite José Yvan Pereira
Published: April 2014

Stability of bubble size in the pulp zone and froth control is an important parameter for a successful flotation process. The present study compares the action of the main frothers in terms of: mean bubble size in the pulp zone, froth stability, surface-tension-lowering ability and reagent participation in flotation of a naturally hydrophobic mineral. Bubble size was determined using a new technique adapted from HYDROMESS, a device designed to measure drop size. The remaining indicators were obtained by determining surface tension and conducting flotation tests with the addition of hydrophobic (graphite) and hydrophilic (calcite) particles. The results indicate that methyl isobutyl carbinol (MIBC) is the most efficient frother in controlling coalescence, with critical coalescence concentration (CCC) reached at 20 ppm. Moreover, this frother has greater potential for selective action, since it increased calcite entrainment by only 2.3% at a concentration of 30 ppm. In flotation tests with a sample of graphite, MIBC produced higher recoveries.
Tools and criteria for the management of temporarily inoperative iron ore mines
Authors: Picarelli Simone , Vieira Gersonito , Resende Alessandro Gomes , Castro Jeanne Michele , Silveira Filipe , Araújo Germano , Beirigo Elder , Cota Ana Carla , Lima Hernani Mota de
Published: April 2014

This paper presents a tool for managing inoperative mines under the responsibility of the Mine Closure and Projects Management/Ferrous Planning and Development Department - Vale S.A., Brazil. Inoperative mines are defined as mines where mining operations are temporarily suspended and there is no definitive strategy regarding their closure. The main management challenges are to: (i) act in a variety of environments and conditions based on action priorities; (ii) identify the main company's image risks; (iii) plan for maintenance and monitoring; (iv) take care of environmental conditions of the sites and follow up audit recommendations; (v) coordinate the field operations and site rehabilitation; (vi) re-evaluate the rehabilitation performance of the site over time, (vii) support the mine closure team. The tool is based on the consolidation of field information through qualitative and quantitative analyses of the environmental risks and quality of each mine. These analyses support the decision-making process and the prioritisation of action to be taken. The tool provides a performance evaluation of the sites, allowing evaluation over time of the maintenance and rehabilitation actions carried out. The input for the tool consists of primary and secondary data (geotechnical and environmental) collected during fieldwork, which is then processed in spreadsheets. These assign prioritisation values based on two main themes: environmental risk and quality. Each of these themes has specific groups of subjects. The prioritization spreadsheet generates thematic maps that present the classification of the mine areas and the action priorities. The tool output is an action plan that guides management, considering all the structures of each site under its responsibility.
Circulating load calculation in grinding circuits
Authors: Silva André Carlos , Silva Elenice Maria Schons , Rezende Ricardo Antonio de
Published: April 2014

A problem for solving mass balances in mineral processing plants is the calculation of circulating load in closed circuits. A family of possible methods for the resolution of these calculations is the iterative method, consisting of a finite loop where in each iteration the initial solution is refined in order to approach the exact solution. The present work presents a low-complexity iterative algorithm for circulating load calculation in mineral processing closed circuits, thus enabling the construction of reliable mass, metallurgical and water balances. The proposed equations on the algorithm were obtained through the analysis of many industrial systems, taking into account the process operational parameters. A validation was performed with real industrial data, in order to ensure a greater reliability of the obtained results. Two different types of closed circuits are presented, each one with different levels of complexity, to clarify the proposed algorithm. With the results, it is possible to affirm that the proposed iterative algorithm can be successfully applied to any kind of closed circuit in mineral processing. The results were satisfactory with respect to processing speed, convergence of the solution and the number of iterations required for the circulating load calculation.
Interação solo-estrutura para sistemas estruturais reticulados sobre fundações rasas
Authors: Pavan R. C. , Costella M. F. , Guarnieri G.
Published: April 2014

Neste artigo apresenta-se um programa para consideração da interação solo-estrutura na análise espacial de estruturas reticulares. O método empregado baseia-se na hipótese de Winkler, que admite molas discretas adjacentes as fundações rasas, simulando a influência dos recalques de apoio em estruturas tridimensionais. Embora o modelo seja 3D e, portanto, todos os seis graus de liberdade de cada apoio possam sofrer deslocamentos devidos a um recalque, neste artigo, a análise foi feita considerando apenas a influência da translação verticaldos apoios. O trabalho consiste em incorporar a metodologia para consideração de apoios flexíveis aos fluxogramas apresentados por Geree Weaver Jr. [1], utilizando o Método da Rigidez, o qual é amplamente empregado para análise de estruturas reticulares. Através da análiseintegrada, contemplando parâmetros da infraestrutura, supraestrutura e do terreno de fundação, comprovou-se que a deformabilidade do solotem influência significativa na redistribuição dos esforços e a vinculação entre solo e a estrutura que melhor descreve o comportamento físicode uma edificação é condição de apoios flexíveis.
Integrating Social Science into Managing Herbicide-Resistant Weeds and Associated Environmental Impacts
Authors: Ervin David , Jussaume Ray
Published: April 2014

Controlling herbicide resistance (HR) and its associated environmental risks is impossible without integrating social and economic science with biophysical and technology aspects. Herbicide resistance is a dynamically complex and ill-structured problem involving coupled natural–human systems that defy management approaches based on simple scientific and technology applications. The existence of mobile herbicide resistance and/or herbicide tolerance traits add complexity because susceptibility to the herbicide is a resource open to all farmers, impacting the weed population. Weed scientists have extensively researched the biophysical aspects and grower perceptions of HR. They also recognize that the “tragedy of the commons” can appear when herbicide resistance is mobile across farms. However, the human structures and processes, especially private and public institutions that influence individual and group decisions about HR, have received little analysis. To start filling that gap, we discuss an integrative management approach to sustainable weed control that addresses the social complexity of farm heterogeneity. For example, the need for a private or public collective mechanism becomes apparent to address common-pool resource (CPR) aspects when one farmer's weed control actions influence their neighbors' situations. In such conditions, sole reliance on education, technical assistance, and other incentives aimed at changing individual grower behavior likely will fail to stem the advance of HR. Social science theories can be used to enrich the understanding of human interaction with the biophysical environment and identify key actors and social change processes influencing those interactions in the case of HR. The short-run economic advantages of herbicides such as glyphosate work against social change to address HR, including the development of collective actions when mobile HR conditions exist. We discuss seven design principles that can improve the efficacy and cost of such collective approaches and draw insights from CPR approaches outside of HR.
Environmental Impact of Glyphosate-Resistant Weeds in Canada
Authors: Beckie Hugh J. , Sikkema Peter H. , Soltani Nader , Blackshaw Robert E. , Johnson Eric N.
Published: April 2014

Glyphosate-resistant (GR) giant ragweed, horseweed, and common ragweed were confirmed in southwestern Ontario, Canada in 2008, 2010, and 2011, respectively. In the western prairie provinces of Alberta and Saskatchewan, GR (plus acetolactate synthase inhibitor-resistant) kochia was discovered in 2011. This symposium paper estimates the environmental impact (EI) of the top herbicide treatments or programs used to manage these GR weed species in the major field crops grown in each region. For each herbicide treatment, EI (per ha basis) was calculated as the environmental impact quotient (EIQ), which quantifies the relative potential risk of pesticide active ingredients on human and ecological health based on risk components to farm workers, consumers, and the environment, multiplied by the application rate (kg ai ha−1). Total EI is defined as EI (per ha basis) multiplied by the application area (i.e., land area affected by a GR weed). It was assumed that all herbicide treatments would supplement the continued usage of glyphosate because of its broad spectrum weed control. For the control of these GR weeds, most treatments contain auxinic or protoporphyrinogen oxidase (PPO)-inhibiting herbicides. The majority of auxinic herbicide treatments result in low (EI ≤ 10) to moderate (11 to 20) EI, whereas all treatments of PPO inhibitors have low EI. Total EI of GR horseweed and kochia will generally be greater than that of giant or common ragweed because of rapid seed dispersal. For recommended herbicide treatments to control GR weeds (and herbicide-resistant weeds in general), EI data should be routinely included with cost and site of action in weed control extension publications and software, so that growers have the information needed to assess the EI of their actions.
Delaying Weed Control Lengthens the Anthesis-Silking Interval in Maize
Authors: Reid Andrew , Gonzalez Victor , Sikkema Peter H. , Lee Elizabeth A. , Lukens Lewis , Swanton Clarence J.
Published: April 2014

Stress caused by early weed competition is known to delay the rate of maize development which may result in a decrease in kernel number. Kernel number in maize is correlated negatively with the length of the anthesis-silking interval (ASI). A short ASI has been identified as an easily measured, visual trait which may identify enhanced drought tolerance in maize. Field studies were conducted to test whether: (1) delaying weed control would result in a lengthening of ASI in both a drought tolerant and non-drought tolerant maize hybrid and (2) the presence of drought tolerance genetics comes at a physiological cost, resulting in a greater yield reduction under weedy conditions. In this study, the response of a drought tolerant hybrid with its non-drought tolerant near-isoline was compared to seven different timings of weed control using wheat as a surrogate competitor. Results confirmed that there was no treatment by hybrid interaction at any site–yr for any of the parameters evaluated. Delaying weed control reduced plant height, leaf tip number, shifted and reduced biomass accumulation, kernel number and grain yield and lengthened ASI for both hybrids. Although yield losses occurred with the delay in weed control timing, no yield differences were observed between hybrids suggesting that there was no additional physiological cost associated with the drought tolerant traits. The drought tolerant hybrid, however, was found to have a shorter ASI, lower kernel number and higher kernel wt compared to the non-drought tolerant hybrid. This study confirmed that delaying weed control can influence the length of ASI, which is an important drought tolerant trait. The lengthening of ASI by early weed competition resulted in a rate of yield loss of 0.13 T ha−1growing degree days (GDD)−1when averaged across both hybrids and all treatments.
Comparison of Aminocyclopyrachlor Absorption and Translocation in Leafy Spurge (Euphorbia esula) and Yellow Toadflax (Linaria vulgaris)
Authors: Lym Rodney G.
Published: April 2014

Aminocyclopyrachlor has provided excellent control of many perennial weed species including leafy spurge, but control of yellow toadflax has been inconsistent.14C-aminocyclopyrachlor absorption was rapid in both leafy spurge and yellow toadflax and averaged 72% 48 h after treatment (HAT). However, translocation within the plant differed by species. More14C translocated to the aboveground portion of yellow toadflax (28% of applied) compared to leafy spurge (16.5% of applied). There was rapid translocation of14C-label to the roots of both species but more reached the belowground portion of leafy spurge than yellow toadflax. Over 12% of applied14C translocated into leafy spurge roots within 24 HAT but declined to 2% by 192 HAT. In comparison, only 2% of applied14C was found in yellow toadflax roots 24 HAT, and just 0.15% remained in belowground plant parts by 192 HAT. The inconsistent long-term control of yellow toadflax with aminocyclopyrachlor is likely due to poor translocation to the root system, which would allow for rapid regrowth in this hard to control perennial species.
Lessons Learned From the History of Herbicide Resistance
Authors: Shaner Dale L.
Published: April 2014

The selection of herbicide-resistant weed populations began with the introduction of synthetic herbicides in the late 1940s. For the first 20 years after introduction, there were limited reported cases of herbicide-resistant weeds. This changed in 1968 with the discovery of triazine-resistant common groundsel. Over the next 15 yr, the cases of herbicide-resistant weeds increased, primarily to triazine herbicides. Although triazine resistance was widespread, the resistant biotypes were highly unfit and were easily controlled with specific alternative herbicides. Weed scientists presumed that this would be the case for future herbicide-resistant cases and thus there was not much concern, although the companies affected by triazine resistance were somewhat active in trying to detect and manage resistance. It was not until the late 1980s with the discovery of resistance to Acetyl Co-A carboxylase (ACCase) and acetolactate synthase (ALS) inhibitors that herbicide resistance attracted much more attention, particularly from industry. The rapid evolution of resistance to these classes of herbicides affected many companies, who responded by first establishing working groups to address resistance to specific classes of herbicides, and then by formation of the Herbicide Resistance Action Committee (HRAC). The goal of these groups, in cooperation with academia and governmental agencies, was to act as a forum for the exchange of information on herbicide-resistance selection and to develop guidelines for managing resistance. Despite these efforts, herbicide resistance continued to increase. The introduction of glyphosate-resistant crops in the 1995 provided a brief respite from herbicide resistance, and farmers rapidly adopted this relatively simple and reliable weed management system based on glyphosate. There were many warnings from academia and some companies that the glyphosate-resistant crop system was not sustainable, but this advice was not heeded. The selection of glyphosate resistant weeds dramatically changed weed management and renewed emphasis on herbicide resistance management. To date, the lesson learned from our experience with herbicide resistance is that no herbicide is invulnerable to selecting for resistant biotypes, and that over-reliance on a weed management system based solely on herbicides is not sustainable. Hopefully we have learned that a diverse weed management program that combines multiple methods is the only system that will work for the long term.
Environmental Implications of Herbicide Resistance: Soil Biology and Ecology
Authors: Kremer Robert J.
Published: April 2014

Soil microbial community structure and activity are linked to plant communities. Weeds may alter their soil environment, selecting for specific rhizosphere microbial communities. Rhizosphere modification occurs for many crop and horticultural plants. However, impacts of weeds in agroecosystems on soil biology and ecology have received less attention because effective weed management practices were developed to minimize their impacts on crop production. The recent development of herbicide resistance (HR) in several economically important weeds leading to widespread infestations in crop fields treated with a single herbicide has prompted a re-evaluation of the effects of weed growth on soil biology and ecology. The objective of this article is to review the potential impacts of herbicide-resistant weeds on soil biological and ecological properties based on reports for crops, weeds, and invasive plants. Persistent weed infestations likely establish extensive root systems and release various plant metabolites through root exudation. Many exudates are selective for specific soil microbial groups mediating biochemical and nutrient acquisition processes. Exudates may stimulate development of microbial groups beneficial to weed but detrimental to crop growth or beneficial to both. Changes in symbiotic and associative microbial interactions occur, especially for arbuscular mycorrhizal fungi (AMF) that are important in plant uptake of nutrients and water, and protecting from phytopathogens. Mechanisms used by weeds to disrupt symbioses in crops are not clearly described. Many herbicide-resistant weeds includingAmaranthusandChenopodiumdo not support AMF symbioses, potentially reducing AMF propagule density and establishment with crop plants. Herbicides applied to control HR weeds may compound effects of weeds on soil microorganisms. Systemic herbicides released through weed roots may select microbial groups that mediate detrimental processes such as nutrient immobilization or serve as opportunistic pathogens. Understanding complex interactions of weeds with soil microorganisms under extensive infestations is important in developing effective management of herbicide-resistant weeds.
Vavilovian Mimicry: Nikolai Vavilov and His Little-Known Impact on Weed Science
Authors: McElroy J. Scott
Published: April 2014

Nikolai Ivanovich Vavilov was an early 20th century Russian plant scientist who was killed by Joseph Stalin in 1943 for his adherence to basic genetic principles. Vavilov is well known within plant breeding and plant evolutionary biology circles, yet the science of Vavilov is just as important to the field of weed science. Specifically, Vavilov proposed that certain weeds adapted to weed control practices to survive in prehistorical agrarian societies. Most would refer to this adaption as crop mimicry, but the term “Vavilovian mimicry” is more apt. Vavilovian mimicry requires three factors: a model—the crop or desirable plant; a mimic—the weed; and an operator—the discriminating agent, possibly human, animal, or machine. In a modern context, it is proposed that weed adaptation to herbicide applications be included as a form of Vavilovian mimicry, with the acknowledgement that the operator is the herbicide. In this context, Vavilovian mimicry is the adaption of the weed mimic to be perceived by the operator as visually, physically, or biochemically indistinguishable from the crop model. This review will cover the history and legacy of Vavilov in a condensed version in the hope that weed scientists will hold this individual in high regard in our future endeavors and begin to acknowledge Vavilov as one of the first scientists to propose that weeds can mimic the attributes of crops.
10% Tumor Diameter Shrinkage on the First Follow-Up Computed Tomography Predicts Clinical Outcome in Patients With Advanced Renal Cell Carcinoma Treated With Angiogenesis Inhibitors: A Follow-Up Validation Study
Authors: Krajewski Katherine M. , Franchetti Yoko , Nishino Mizuki , Fay André P. , Ramaiya Nikhil , Van den Abbeele Annick D. , Choueiri Toni K.
Published: April 2014

Background.

Vascular endothelial growth factor (VEGF)-targeted agents are standard therapies for metastatic renal cell carcinoma (mRCC), associated with variable tumor shrinkage. Response Evaluation Criteria in Solid Tumors (RECIST) is of limited utility in this setting, and other imaging changes are sought to reliably predict outcome early. We aim to validate 10% tumor shrinkage as the best early indicator of outcome.

Methods.

In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study, 66 mRCC patients with 165 lesions on clinical trials of VEGF-targeted agents underwent thoracic and abdominal computed tomography at baseline and at first follow-up after therapy. Measurements were performed according to RECIST and tumor shrinkage of ≥10% decrease in sum of the longest diameter (−10%SLD). Correlation with time-to-treatment failure (TTF) and overall survival (OS) were compared and stratified by response to the radiologic criteria. Receiver-operating characteristics (ROC) analysis yielded the optimal threshold change in SLD, defining patients with prolonged survival.

Results.

More than −10%SLD significantly differentiated responders from nonresponders (median TTF 8.4 vs. 4.1 months, p = .001), whereas partial response by RECIST did not (median TTF 6.9 vs. 5.5 months in responders vs. nonresponders, p = .34). −10%SLD was also significantly predictive of OS (median OS 35.1 vs. 15.0 months in responders vs. nonresponders, p = .003). ROC curve analysis yielded −9.3% in SLD as the optimal threshold for response/no response.

Conclusion.

Ten percent tumor shrinkage is validated as a reliable early predictor of outcome in mRCC patients receiving VEGF-targeted therapies and may provide a practical measure to guide therapeutic decisions.
Numerical simulation of creep and shrinkage in widened concrete bridges
Authors: Wen Qing-Jie , Jing Hong-Wen
Published: April 2014

Creep and shrinkage of concrete can cause cracking or damage when original old bridges that are widened directly by new bridges in a lateral direction experience constrained stress and deformation. This paper presents a numerical method to evaluate creep and shrinkage based on Newmark's methods. In addition, an example of an actual bridge widening process was analysed to obtain displacement and stress redistribution and compared with calculations from a finite-element method. The results validate the precision of the numerical method and show that the displacement of the new and old bridges, as well as the stress exerted on them, will not lead to concrete cracking. However, creep and shrinkage make significant contributions in the first 3 months and therefore it is suggested that bridge widening is carried out when new bridges are 3 months old.
Yields and Profitability during and after Transition in Organic Grain Cropping Systems
Authors: Caldwell Brian , Mohler Charles L. , Ketterings Quirine M. , DiTommaso Antonio
Published: April 2014

The transition period to organic grain production presents an economic obstacle for farmers, and early management may affect subsequent crop performance. Using a corn–soybean–winter spelt/red clover [Zea mays L.–Glycine max (L.) Merr.–Triticum spelta L./Trifolium pratense L.] rotation in central New York, we compared yields and economics in four organic cropping systems during and after transition. These were high fertility (HF), low fertility (LF), enhanced weed management (EWM), and reduced tillage (RT). Corn and soybean yields in HF, LF, and EWM were similar among systems throughout the experiment and averaged 65 and 91%, respectively, of those in surrounding Cayuga County (CC) during transition. In the first year after transition, HF, LF, and EWM corn yields averaged 63% of CC, but after that 98 to 114% of CC. Soybean yield trends relative to CC remained the same after transition. Transitional spelt yields tended to be higher in HF and EWM than in LF. Spelt yields after transition were variable. Starting in 2006, RT yields were lower than other organic systems in all crops due to equipment problems. Weeds generally increased in all systems over 6 yr, and reached the highest biomass levels in RT and HF. Under our soil and climate conditions, higher fertility amendments in HF compared with LF increased weed biomass but not corn or soybean yield. Economic budgets revealed lower relative net returns (RNR) during transition for the HF, LF, and EWM systems compared with values calculated from CC yields and practices, but higher RNR thereafter.
Residual Effects of Potassium to Cotton on Corn Productivity under No‐Tillage
Authors: Zhou Guisu , Yin Xinhua , Verbree David A.
Published: April 2014

The long‐term residual effects of K applications to preceding cotton (Gossypium hirsutum L.) on subsequent corn (Zea mays L.) is largely unknown under no‐tillage. A cotton field experiment was conducted on a no‐tilled Loring silt loam (fine‐silty, mixed, active, thermic Oxyaquic Fragiudalf) at Jackson, TN, during 1995 to 2008 with the K treatments of 0, 28, 56, 84, 112, 140, and 168 kg ha−1applied to the same plots each year. From 2009 through 2011, corn was no‐till planted on the previous cotton trial without further K fertilization. Incremental gains in corn leaf K responses were consistent with increases in the K application rate for previous cotton. A significant quadratic relationship was observed between corn yields and K application rates in 2010 and 2011 with corn yield peaking at the K rate of 94 kg ha−1 in 2010 and 84 kg ha−1 in 2011. Potassium removal by grain ranged from 2.54 to 3.55 kg K Mg−1 of grain yield. For the 28 kg K ha−1 rate and those higher K rates, soil K buffering capacity followed an exponential decline as the initial soil test K level increased. Surface broadcasting of K fertilizer at the recommended rate of 56 kg K ha−1 or above to preceding cotton for 14 yr and relying on the residual K fertilizer for the subsequent corn for at least 3 yr without further K fertilization might be a viable K management practice on high K fields under no‐tillage.
Grazing Winter Rye Cover Crop in a Cotton No‐Till System: Yield and Economics
Authors: Schomberg H. H. , Fisher D. S. , Reeves D. W. , Endale D. M. , Raper R. L. , Jayaratne K. S. U. , Gamble G. R. , Jenkins M. B.
Published: April 2014

Winter annual cover crop use is limited in conservation management systems in the United States. Grazing cover crops could encourage cover crop adoption if returns offset establishment costs without reducing crop yields. A 4‐yr field experiment was conducted near Watkinsville, GA, in which a rye (Secale cereale L.) cover crop was grazed by cattle or roller‐crimped before planting cotton (Gossypium hirsutum L.). Cattle consumed about 2.4 Mg ha−1 of forage annually but amounts were variable due to weather conditions. Rye residue remaining at cotton planting averaged 6.7 Mg ha−1 for non‐grazed compared with 1.7 Mg ha−1 for grazed treatments. Cotton yields tended to be better in the non‐grazed treatment but were significantly different only in 2009 when yields were reduced in the grazed treatment due to soil compaction. Four‐year average lint yield was 120 kg ha−1 greater for the non‐grazed treatment. Cotton fiber quality parameters were generally better in the non‐grazed treatment but not enough to change crop price. Differences between grazed and non‐grazed returns ranged from $–26 to $355 and averaged $81 ha−1 when based on market year prices. The difference in average return increased to $110 ha−1 when based on 2012 market year prices. Although negative effects of soil compaction were observed the final year, returns from grazing have the potential to offset establishment costs of a rye cover crop and increase profits for cotton producers in the Southern Piedmont of the United States.
Agronomic Response of Soybean Varieties to Plant Population in the Guinea Savannas of Nigeria
Authors: Kamara Alpha Y. , Ewansiha Sylvester U. , Boahen Steve , Tofa Abdullahi I.
Published: April 2014

The agronomic responses of three contrasting soybean [Glycine max (L.) Merr.] varieties to plant populations were examined in two distinct agro‐ecological locations (at Samaru Zaria and Samaru‐Kataf), both in the Guinea savanna of northern Nigeria in 2009, 2010, and in 2011 growing seasons. Three soybean varieties: TGx1835‐10E, TGx1904‐6F, and TGx1448‐2E differing in maturity duration (early, medium, and late maturing, respectively), were evaluated at four plant populations (266,700, 333,300, 533,300, and 666,700 plants ha−1) using a split plot arrangement in randomized complete block design with three replications. The plant populations were the main plots, whereas varieties were subplots. The proportion of intercepted photosynthetically active radiation (IPAR) and leaf area index (LAI) increased with increasing plant population at both locations, indicating that high leaf area indices and high degree of canopy closure at higher plant population intercepted more light than the canopy at lower population and subsequently resulted in relatively high grain and fodder yields. At both locations, optimum plant populations ranged from 533,300 to 666,700 plants ha−1 across the years. The northern Guinea savanna location (Samaru Zaria) produced more pods m−2, grain yield, and fodder at higher plant populations than that at the southern Guinea savanna (Samaru‐Kataf). Varieties TGx1448‐2E and TGx1904‐6F intercepted higher proportion of IPAR had higher LAI and produced a greater number of pods m−2, seeds m−2, grain yield, and fodder than TGx1835‐10E at both locations in years of good rainfall. These data suggest that soybean yields in the Guinea savanna of northern Nigeria can be increased using higher plant populations than those currently recommended.
Age of No‐Till System and Nitrogen Management on Common Bean Nutrition and Yield
Authors: Soratto Rogério P. , Perez Adelson A. G. , Fernandes Adalton M.
Published: April 2014

In the no‐till (NT) system, N availability may change depending on the number of years since NT was adopted. Thus, an experiment was conducted in a Typic Rhodudalf in Botucatu, São Paulo, Brazil, to evaluate the influence of the age (timing of establishment) of the NT system and N fertilizer management on the nutrition, yield, and N‐use efficiency (NUE) of common bean (Phaseolus vulgaris L.) crop. Treatments included four management systems (a newly implemented NT system, an established NT system, a newly implemented NT with an application of 60 kg ha−1 N at pre‐sowing, and an established NT with an application of 60 kg ha−1 N at pre‐sowing) and four N rates (0, 30, 60, and 120 kg ha−1) sidedressed at the V4 stage of common bean. The age of the NT system did not affect common bean nutrition or its response to sidedressed N application, but the established NT system, regardless of N application at pre‐sowing, provided a slightly greater common bean yield. In both the newly implemented and established NT systems, N fertilization increased the aboveground biomass, seed yield, and protein concentration in seeds. Even with the application of N at pre‐sowing, seed yield increased in response to sidedressed N fertilization in all the management systems. The NUE by common bean was greater in treatments receiving N at pre‐sowing. A higher seed yield and NUE of common bean grown in the NT systems after grass was achieved with the combined application of N at pre‐sowing and sidedressing.
Yield and Nutrient Concentration Response to Switchgrass Biomass Harvest Date
Authors: Gouzaye Amadou , Epplin Francis M. , Wu Yanqi , Makaju Shiva O.
Published: April 2014

Timing of biomass removal from stands of switchgrass (Panicum virgatum L.) impacts the nutrient content of harvested material and fertilizer requirements for subsequent growing seasons. This study was conducted to determine the change in N, P, and K content of harvested switchgrass biomass as a function of the harvest date and to determine the economic consequences of an extended harvest window. Data were produced in a randomized complete block study conducted at the Oklahoma Agricultural Experiment Station, Stillwater, with six replications over three harvest seasons from November of 2007 to March of 2010. Treatments on the established stand of cultivar Kanlow consisted of five harvest dates separated by about 30 d beginning in late November. Regression equations were used to fit yield and N, P, and K concentration response to the harvest date. Delaying harvest beyond December resulted in an average 5.4% decline in harvested biomass per month. Delaying harvest beyond November did not result in a significant change in the N concentration in the harvested biomass. However, delaying harvest did result in a significant decrease in both P and K content in the harvested biomass. Point estimates from the response functions were used to estimate production cost for each of five harvest dates beginning with 30 November and ending with 30 March. The quantities of P2O5 and K2O fertilizer that would be required to replace the P and K removed with the biomass were used in the budgets. Biomass production cost was similar across harvest dates.