bluuebunny/crossref_metadata_2025 huggingface dataset:
Aggregate stability as affected by short and long-term tillage systems and nutrient sources of a hapludox in southern Brazil
Authors: Veiga Milton da , Reinert Dalvan José , Reichert José Miguel
Published: October 2009

The ability of a soil to keep its structure under the erosive action of water is usually high in natural conditions and decreases under frequent and intensive cultivation. The effect of five tillage systems (NT = no-till; CP = chisel plowing and one secondary disking; CT = primary and two secondary distings; CTb = CT with crop residue burning; and CTr = CT with removal of crop residues from the field), combined with five nutrient sources (C = control, no nutrient application; MF = mineral fertilizers according to technical recommendations for each crop; PL = 5 Mg ha-1 y-1 fresh matter of poultry litter; CM = 60 m³ ha-1 y-1 slurry cattle manure; and SM = 40 m³ ha-1 y-1 slurry swine manure) on wet-aggregate stability was determined after nine years (four sampled soil layers) and on five sampling dates in the 10th year (two sampled soil layers) of the experiment. The size distribution of the air-dried aggregates was strongly affected by soil bulk density, and greater values of geometric mean diameter (GMD AD) found in some soil tillage or layer may be partly due to the higher compaction degree. After nine years, the GMD AD on the surface was greater in NT and CP compared to conventional tillage systems (CT, CTb and CTr), due to the higher organic matter content, as well as less soil mobilization. Aggregate stability in water, on the other hand, was affected by the low variation in previous gravimetric moisture of aggregates, which contributed to a high coefficient of variation of this attribute. The geometric mean diameter of water-stable aggregates (GMD WS) was highest in the 0.00-0.05 m layer in the NT system, in the layers 0.05-0.10 and 0.12-0.17 m in the CT, and values were intermediate in CP. The stability index (SI) in the surface layers was greater in treatments where crop residues were kept in the field (NT, CP and CT), which is associated with soil organic matter content. No differences were found in the layer 0.27-0.32 m. The effect of nutrient sources on GMD AD and GMD WS was small and did not affect SI.
Influence of fungicide seed treatment on soybean nodulation and grain yield
Authors: Zilli Jerri Édson , Ribeiro Karen Gonçalves , Campo Rubens José , Hungria Mariangela
Published: October 2009

Biological N2 fixation is a major factor contributing to the increased competitiveness of Brazilian soybeans on the international market. However, the contribution of this process may be limited by adverse conditions to symbiotic bacteria, such as fungicide seed treatments. This study aimed to evaluate the effects of the fungicides carbendazim + thiram and carboxin + thiram on soybean nodulation, plant growth and grain yield. Two field experiments were carried out in the Cerrado region of the State of Roraima, in a soil with a low organic matter content and no soybean bradyrhizobia. In 2005, seeds were treated with fungicide carbendazim + thiram and commercial inoculants containing the Bradyrhizobium elkanii strains SEMIA 5019 and SEMIA 587 and B. japonicum strains SEMIA 5079 and SEMIA 5080. In 2006, soybean seeds were treated with the fungicides carbendazim + thiram or carboxin + thiram and inoculated separately with each one of the four strains. The plants were evaluated for number of nodules and dry weight, shoot dry weight and total N accumulated in shoots 35 days after plant emergence, while grain yield and N grain content were determined at harvest. Both fungicides reduced soybean nodulation, especially in the presence of B. elkanii strains. The fungicide carbendazim + thiram reduced nodulation by about 50 % and grain yield by more than 20 % (about 700 kg ha-1), in the treatment inoculated with of strain SEMIA 587.
Distribuição e incerteza da acidez de um latossolo vermelho-amarelo húmico sob cultivo de café
Authors: Silva Samuel de Assis , Lima Julião Soares de Souza , Souza Gustavo Soares de , Xavier Alexandre Candido
Published: October 2009

Com o desenvolvimento da agricultura, a utilização de novas alternativas na avaliação das propriedades que influenciam o rendimento das plantas tornou-se indispensável para melhor manejar o sistema agrícola. O objetivo deste trabalho foi utilizar uma ponderação por meio da modelagem fuzzy para estudar, com base em atributos químicos do solo, a propagação de incertezas da acidez de um Latossolo Vermelho-Amarelo húmico cultivado com café arábica. As amostragens de solo foram realizadas na profundidade de 0-20 cm, em uma malha totalizando 50 pontos. Os atributos avaliados foram: pH em H2O, acidez trocável (Al3+), acidez potencial (H + Al) e saturação por Al (m). Os dados foram analisados pela estatística descritiva e pela geoestatística. Utilizou-se um sistema de classificação fuzzy e os atributos descritos para inferir sobre a acidez do solo. A lógica fuzzy, pelo algoritmo utilizado, teve um bom desempenho na caracterização e no mapeamento das incertezas da acidez do solo em questão.
Educação e responsabilidade empresarial: "novas" modalidades de atuação da esfera privada na oferta educacional
Authors: Silva Maria Vieira , Souza Silvana Aparecida de
Published: October 2009

A intensificação da simbiose entre as esferas pública e privada é coetânea das mutações operadas em nível macrossocial, derivadas, sobretudo, dos processos de reforma do Estado e das mudanças no mundo do trabalho. Neste artigo colocaremos em relevo os arenosos terrenos do espaço público e a expansão da intervenção do setor privado. Recuperamos os discursos, políticas e práticas do empresariado para a educação escolar mediante os dispositivos da responsabilidade social empresarial e do trabalho voluntário. Evidencia-se que esses mecanismos estão em consonância com a lógica mercantil do capitalismo neoclássico mediante duas dimensões: a ambientação do (futuro) trabalhador aos processos de reestruturação produtiva e a naturalização da "solidariedade entre emprego e não-emprego", por meio do "trabalho voluntário" neste novo ciclo de produção da mais-valia.
Educação de adultos na educação ao longo da vida: desenvolvimentos atuais e interdependentes na Alemanha e na Europa, a caminho da VI CONFINTEA
Authors: Hinzen Heribert
Published: October 2009

A educação e a aprendizagem de adultos têm recebido mais atenção e reconhecimento a partir do conceito de aprendizagem ao longo da vida, que se torna agora o principal paradigma para a teoria e a prática educacionais. Este movimento se acentua no contexto de organismos como a Unesco, a União Europeia e a Associação Alemã de Educação de Adultos (DVV), no caso da Alemanha. Há claras indicações de que cada um desses organismos exerce mútua influência sobre os outros, por meio das políticas, programas, modelos e até mesmo pela administração de recursos financeiros. Isto é exemplificado no artigo pela indicação de processos que vêm ganhando importância nos últimos anos, na preparação da VI Conferência Mundial de Educação de Adultos - VI Confintea.
A influência das atividades mineradoras na alteração do pH e da alcalinidade em águas fluviais: o exemplo do rio Capivari, região do carste paranaense
Authors: Fritzsons Elenice , Mantovani Luiz Eduardo , Chaves Neto Anselmo , Hindi Eduardo Chemas
Published: October 2009

As atividades de mineração causam vários tipos de impactos ao meio ambiente. Este trabalho apresenta um estudo de impacto sobre recursos hídricos superficiais desenvolvidos numa bacia hidrográfica na região metropolitana de Curitiba (PR), onde se observaram modificações no pH e na alcalinidade nas águas do rio Capivari ocorridas num intervalo médio de doze anos. Foram avaliados 387 dias de amostragem da série 1986/1987 e 1.095 dias da série 1998/2000. Comparando-se as duas séries, observou-se que, ao longo deste período (1986-2000), a média do pH elevou-se, em média, 0,5 unidade, enquanto a alcalinidade aumentou em 15%. De 1980 a 2001, as áreas de mineração desta mesma bacia tiveram uma expansão de aproximadamente 47.000 m²/ano. Avaliações ao longo do rio revelaram, nos locais à jusante e mais próximos das pedreiras, que o pH apresenta valores mais altos, tornando-se alcalino, e a condutividade elétrica aumenta. Esses dados confirmam a hipótese de que a expansão das áreas de mineração provocaria alterações nos valores de pH e de alcalinidade das águas do rio Capivari.
O emprego da análise de imagem na determinação da distribuição de tamanho de partículas da areia presente no esgoto sanitário
Authors: Prado Gustavo Silva do , Campos José Roberto
Published: October 2009

É consensual, no meio técnico, que unidades de desarenação devem reter partículas discretas de elevada velocidade relativa de sedimentação (por exemplo: areia, silte, cinzas, semente de frutas etc); e que desarenadores capazes de remover grãos de areia de tamanho maior ou igual a 0,2 mm removem a maior parte dos materiais que ocasionam problemas operacionais em estações de tratamento de esgoto (ETE). Entretanto, não existe concordância acerca da forma de se determinar a concentração ou a distribuição granulométrica de tais materiais no esgoto sanitário. O presente artigo apresenta um método para determinar a distribuição granulométrica da areia presente no esgoto sanitário, o qual se baseia no emprego de técnicas de análise de imagens digitais. A aplicação do método proposto demonstrou que, em média, 84% da massa de areia carreada pelo esgoto sanitário afluente da ETE Jardim das Flores (Rio Claro, SP) era composta por partículas maiores ou iguais a 0,2 mm.
Análise morfológica do arco superior de portadores de fissura labiopalatal submetidos a diferentes protocolos de expansão rápida maxilar: avaliação das alterações maxilares
Authors: Souza Maíra Massuia de , Menezes Luciane Macedo de , Rizzatto Susana Maria Deon , Vieira Gustavo da Luz , Meneguzzi Ricardo Damo
Published: October 2009

INTRODUÇÃO: em portadores de malformações labiopalatais, a boa conformação do arco superior constitui um dos principais requisitos para a obtenção de uma oclusão adequada e para o aperfeiçoamento estético e funcional. Para tanto, a expansão ortopédica da maxila é frequentemente necessária, uma vez que é alta a incidência de colapso dos segmentos. OBJETIVOS: analisar, por meio de modelos de gesso, as dimensões do arco superior de 15 portadores de fissura transforame incisivo unilateral, com deficiências transversal e anteroposterior da maxila, submetidos à expansão com dois diferentes protocolos de ativação. MÉTODOS: um grupo foi submetido à Expansão Rápida da Maxila (ERM) com protocolo de ativação convencional (Grupo 1), enquanto no outro grupo foi utilizado o protocolo de ativação preconizado por Liou e Tsai em 2005, com expansões e contrações alternadas (Grupo 2), sendo ambos submetidos posteriormente à protração maxilar com máscara de tração reversa. Os modelos foram obtidos em dois momentos: antes da cimentação do disjuntor do tipo Haas modificado (T1) e após 24 semanas de tratamento (T2). As distâncias transversais entre os primeiros pré-molares superiores (região anterior) e a distância entre os primeiros molares superiores (região posterior) foram registradas com um paquímetro digital. Os dados obtidos foram submetidos ao teste t de Student. RESULTADOS E CONCLUSÕES: os dois protocolos de ativação mostraram-se igualmente efetivos na expansão maxilar, não havendo diferença entre os grupos em relação ao aumento transversal obtido.
O tratamento da Classe III: revisão sistemática - Parte I. Magnitude, direção e duração das forças na protração maxilar
Authors: Perrone Anna Paula Rocha , Mucha José Nelson
Published: October 2009

INTRODUÇÃO: para o tratamento da Classe III durante o crescimento, a protração maxilar é a terapia mais relatada na literatura. Durante o tratamento, é requerida especial atenção à mecânica utilizada para a correção do problema. OBJETIVO: sintetizar as informações relativas à magnitude, direção e tempo diário da aplicação das forças, por meio de uma revisão sistemática. MÉTODOS: estudos foram identificados a partir de uma pesquisa eletrônica no Medline database - Entrez PubMed (178 artigos) e Bireme (550 artigos), no período de janeiro de 1983 a dezembro de 2008. Após um criterioso processo de inclusão e exclusão, 56 estudos primários foram selecionados e submetidos a um segundo processo de seleção, restando 39 artigos. Foram calculados a média e o desvio-padrão, bem como os valores mínimos e máximos para a magnitude, a direção e a quantidade de horas de uso das forças de protração maxilar. RESULTADOS E CONCLUSÃO: as médias de magnitude, direção e duração das forças de protração maxilar foram de, respectivamente, 447,8 gramas, 27,5 graus de inclinação em relação ao Plano Oclusal, e 15,2 horas por dia.
Lipídeos na nutrição de cães e gatos: metabolismo, fontes e uso em dietas práticas e terapêuticas
Authors: Trevizan Luciano , Kessler Alexandre de Mello
Published: October 2009

A partir do desenvolvimento de métodos mais precisos para a avaliação de lipídeos, diversos compostos têm sido descobertos e estudados como forma de enriquecer e melhorar dietas para atender às necessidades dos animais. O triglicerídeo é o principal componente lipídico da dieta e fonte de ácidos graxos que são utilizados para a síntese de outros lipídicos importantes como os fosfolípideos. Os ácidos graxos dos fosfolipídeos possuem papel fundamental na sinalização celular e são substratos das enzimas específicas durante o processo de produção de mediadores de respostas imunológicas. Diversos estudos têm evidenciado a participação de grupos de ácidos graxos das séries ômega 3 e 6 influenciando as respostas inflamatórias em cães e gatos. A deficiência de ácido araquidônico em gatos, por exemplo, pode ser suprida pelo acréscimo de AA pré formado ou pela inclusão de ácido γ-linolênico na dieta, que mostrou-se eficiente na sustentação dos níveis de ácido araquidônico exigidos por gatos adultos. Há evidências de que ácidos graxos de cadeia média (AGCM) proporcionam maior incremento calórico durante o processo de oxidação celular, sugerindo sua funcionalidade sobre o controle da obesidade. Outros compostos lipídicos têm sido avaliados quanto a sua participação no processo de controle de ganho de peso. A ausência de um AA nos diacilgliceróis (DAG) pode ser na posição sn 2 ou sn 3 do glicerol gerando DAGs diferentes. O 1,3 DAG quando comparado ao TAG resulta em diferentes efeitos metabólicos que suportam a hipótese de que o acréscimo de DAG na dieta aumenta a oxidação hepática ou intestinal de lipídeos, limitando a deposição de ácidos graxos em triglicerídeos junto ao tecido adiposo.
Avanços recentes em nutrição de larvas de peixes
Authors: Conceição Luís Eugénio Castanheira da , Aragão Cláudia , Richard Nadège , Engrola Sofia , Gavaia Paulo , Mira Sara , Dias Jorge
Published: October 2009

Os requisitos nutricionais de larvas de peixes são ainda mal compreendidos, o que leva a altas mortalidades e problemas de qualidade no seu cultivo. Este trabalho pretende fazer uma revisão de novas metodologias de investigação, tais como estudos com marcadores, genómica populacional, programação nutricional, génomica e proteómica funcionais, e fornecer ainda alguns exemplos das utilizações presentes e perspectivas futuras em estudos de nutrição de larvas de peixes.
Precision livestock production: tools and concepts
Authors: Laca Emilio A.
Published: October 2009

Precision livestock production (PLP) is the augmentation of precision agriculture (PA) concepts to include all components of agroecosystems, particularly animals and plant-animal interactions. Soil, plants and soil-plant interactions are the subjects of PA or site-specific farming, where the main principle is to exploit natural spatial heterogeneity to increase efficiency and reduce environmental impacts. For the most part, PA has been studied and developed for intensive cropping systems with little attention devoted to pastoral and agropastoral systems. PLP focuses on the animal component and exploits heterogeneity in space and among individual animals towards more efficient and environmentally friendly production. Within PLP, precision grazing consists of the integration of information and communication technologies with knowledge about animal behavior and physiology to improve production of meat, milk and wool in grazing conditions. Two main goals are to minimize overgrazing of sensitive areas and to maximize the quality of the product through enhanced traceability. An integrated precision grazing system is outlined with its components: sensors of animal position, behavior and physiological status, real-time transmission of information to a decision support system, and feed-back through a series of actuators. Control of animal movement and diets is based on knowledge about species specific responses to various stimuli within the paradigms of flavor aversions and operant conditioning. Recent advances in the technologies and instrumentation available are reviewed briefly and linked to current livestock identification systems. The precision grazing vision is presented in full and the areas that need further research and development are discussed.
Improving grassland profitability in the Mid-continental USA by breeding for improved forage digestibility: lessons learned and applications to South American grasslands
Authors: Vogel Kenneth Paul , Miranda Cesar Heraclides Behling
Published: October 2009

In the early 1970's research was initiated by the cooperative USDA-ARS and University of Nebraska grass breeding program to develop perennial grasses adapted to the mid-continental USA with improved forage quality. The initial breeding and animal evaluation work focused on switchgrass (Panicum virgatum) but has since expanded to several other warm-and cool-season perennial grasses. The in vitro dry matter digestibility (IVDMD) test was selected as the measure of forage quality that was used in the breeding work because of its previous successful application on improving bermudagrass (Cynodon dactylon). In all of the grass species that we have studied to date, there is genetic variability for IVDMD and forage yield. IVDMD is a heritable trait with narrow sense heritability's ranging from 0.2 to 0.4 which are similar to heritability's for forage yield. If significant improvements or difference in IVDMD (> 1%) can be detected in small plot trials (r=6), differences in cattle gains among experimental strains or cultivars can be demonstrated in grazing trials. Averaged over both cool- and warm-season grasses, a 1% increase in in vitro dry matter digestibility (IVDMD) generally leads to a 3.2% increase in average daily gains of beef cattle. Because increased IVDMD generally does not result in a decrease in forage yield, this results in a net increase in animal production per hectare of land.
Revision of the Southern African Pollen Beetle GenusAnthystrix(Coleoptera: Nitidulidae: Meligethinae)
Authors: Audisio P , Cline A R , Lamanna F , Trizzino M , Antonini G , Mancini E , Biase A De
Published: October 2009

The pollen beetle genus AnthystrixKirejtshuk, 1981 previously included six South African species characterized by unusual dimorphic development of male antennal characters. The genus is revised and three new species are described from South Africa, including Anthystrix endroedyi new species, Anthystrix flabellicornis new species, and Anthystrix megalocera new species. Anthystrix luculentaKirejtshuk & Easton 1988, Anthystrix rotundiclavaKirejtshuk & Easton 1988, and Anthystrix martini (Grouvelle, 1899) need to be transferred to two new undescribed genera. These new genera will globally include ≈20 species, most of which remain undescribed or previously attributed to the unrelated genus Meligethinus Grouvelle, 1906. One new synonymy is proposed: Meligethinus uhligiKirejtshuk & Easton, 1988, = Pria martiniGrouvelle, 1899, syn. nov. Larval host plants of Anthystrix species are reported as dioecious Asteraceae trees within the tribe Tarchonantheae (Tarchonanthus). An identification key to all Anthystrix species is provided.
Leg Regeneration Trade-Offs in the Twostriped Walkingstick (Phasmatodea: Pseudophasmatidae)
Authors: Maginnis Tara L , Redmond Christopher R
Published: October 2009

Appendage regeneration is a unique tool to study resource allocation trade-offs; the resources allocated to grow an appendage a second time can come at the expense of other structures. We studied the effects of both front and hind leg regeneration on a suite of traits in Anisomorpha buprestoides (Stoll) (Phasmatodea: Pseudophasmatidae), the twostriped walkingstick. This species is ideal for resource allocation questions because it has a relatively long life history as well as a large group of traits to measure for any potential trade-offs (including large defensive glands in the thorax that are used to deter predators). For females, there were no apparent trade-offs with respect to antennae, eyes, defensive glands, nonregenerated legs, cerci, genital plates, and/or body size. In males, there were no also no apparent trade-offs with respect to antennae, eyes, defensive glands, nonregenerated legs, cerci, or testes, but males that regenerated a leg were larger (but not heavier) than nonregenerating males. Future work at the physiological level will hopefully elucidate the nature of acquisitionallocation trade-offs in phasmids, and how such trade-offs may have shaped their evolution.
Saliva or Regurgitated Nectar? What Heliconius Butterflies (Lepidoptera: Nymphalidae) Use for Pollen Feeding
Authors: Eberhard Stefan H , Hikl Anna L , Boggs Carol L , Krenn Harald W
Published: October 2009

The Neotropical Heliconius butterflies are well known to supplement their nectar diet by active pollen collecting. They extract proteins and free amino acids from pollen grains, exhibiting a particular behavior that involves the use of a fluid of uncertain origin. It has been assumed that this fluid is either regurgitated nectar or saliva, because for anatomical reasons a butterfly is able to release only these two fluids through its proboscis. In an experimental approach, 27 individuals of Heliconius melpomene (L.) were given red-dyed sugar solution and subsequently we observed whether the fluid used in pollen feeding was dyed or not dyed. Because regurgitated nectar should contain sugar, fluid samples were taken from the proboscis of butterflies from natural populations in Costa Rica. Samples of 44 individuals from seven species were tested for the presence of fructose and glucose with the aid of aniline phthalate. This study is the first detailed investigation of the origin of the fluid used by Heliconius butterflies in pollen feeding. The results are discussed in terms of already existing hints in literature concerning the true nature of that fluid.
Population Structure of Porthetes hispidus (Coleoptera: Curculionidae), a Pollinator of the African Cycad Encephalartos friderici-guilielmi
Authors: Downie D A , Williams J G
Published: October 2009

Porthetes hispidus (Roheman) (Coleoptera: Curculionidae: Amorphocerini) is thought to be the primary pollinator of and is completely host specific to Encephalartos firiderici-guilielmi Lehmann, which is considered threatened. It is distributed across the Eastern Cape of South Africa. Here, genetic diversity and structure of a cycad-associated weevil, P. hispidus, was investigated using the cytochrome oxidase I (COI) and elongation factor la genes (EF-1α). Samples were taken from nine populations on isolated colonies of the host plant from across its known range. Nucleotide and haplotype diversity were moderate to high. Little to no phylogeographic structure was found, and very low values of FST and high values of Nm (COI: FST = 0.0759, Nm = 3.04; EF-1α: FST = -0.0175, Nm = ∞) indicated high levels of gene flow despite current geographical disjunctions. These data suggest that isolated colonies of E.friderici-guilielmi maintain a viable population of pollinators. However, more rapidly evolving markers may reveal current genetic differentiation that did not exist in the past.
Evolutionary Differentiation of Fitness Traits Across Multiple Geographic Scales inAedes albopictus(Diptera: Culicidae)
Authors: O'Donnell Deborah , Armbruster Peter
Published: October 2009

Aedes albopictus (Skuse) (Diptera: Culicidae) is an invasive, container-inhabiting mosquito that was introduced into North America from Japan in 1985. Although previous studies using neutral biochemical markers have found high levels of population differentiation across both the North American and global distribution of Ae. albopictus, relatively little is known regarding evolutionary differentiation of life history traits underpinning fitness. We performed common-garden and line-cross experiments to examine the genetic differentiation of fitness (r')and underlying performance traits at three spatial scales: 1) local (among populations within Florida), 2) regional (between populations from Florida and New Jersey), and 3) long distance (between populations from Florida and Hawaii, Malaysia, and Japan). We found that North American populations (Florida and New Jersey) had lower fitness (r') than populations from outside North America (Hawaii, Malaysia, and Japan). Bivariate means of female, but not male, pupal mass and developmental time differed among regions (Florida, New Jersey, outside North America). Larval survivorship did not differ among regions nor among populations within regions, whereas size-specific fecundity varied among populations within regions but not among regions. Population crosses resulted in significant heterosis and outbreeding depression Of F1 hybrids but the results of crossing did not depend on the geographic distance separating parental populations in a consistent manner. Together, our results imply a role for local genetic drift affecting the life-history differentiation of Ae. albopictus populations. These conclusions corroborate previous studies of population structure based on neutral biochemical markers.
Neuronal insulin receptor substrate 2 (IRS2) expression is regulated by ZBP89 and SP1 binding to the IRS2 promoter
Authors: Udelhoven Michael , Pasieka Mareike , Leeser Uschi , Krone Wilhelm , Schubert Markus
Published: October 2009

Since neuronal insulin receptor substrate 2 (IRS2)-mediated signals coordinate key processes in rodent physiology such as food intake, fertility, longevity, and aging-related behavior, we analyzed the mechanisms of neuronal IRS2 expression in neuroblastoma (SHSY5Y) and hypothalamic (GT1-7) cell lines. Using dual luciferase reporter assays and IRS2 promoter deletion constructs, we identified a regulatory cassette within the IRS2 promoter between −779 and −679 bp from the translational start which is responsible for ∼50% of neuronal IRS2 promoter activity. Chromatin immunoprecipitation assays and electromobility shift assay revealed four overlapping ZBP89/specificity protein 1 (SP1) binding sites which alternatively bind to ZBP89 (ZNF148 as listed in the HUGO Database) or SP1. Activation of this cassette is inhibited by phosphoinositide-3-kinase (PI3K) via increased ZBP89 binding to the promoter. Serum starvation caused increased SP1 binding at one specific SP1 site and decreased binding to another, proving a regulatory interaction between the different binding sites within this promoter cassette to tightly control IRS2 expression. Mutants containing all the possible combinations of one, two, three, or all the four SP1 binding sites of the IRS2 promoter revealed that SP1 binding to one particular site is most important for promoter activation. Stable downregulation of ZBP89 using siRNA substantially increased IRS2 mRNA and protein expression. Thus, alternative binding of ZBP89 or SP1 to the described region in the IRS2 promoter regulates neuronal IRS2 expression in a PI3K-dependent manner.
Nitrogen Fate in Drainage Ditches of the Coastal Plain after Dredging
Authors: Shigaki Francirose , Schmidt John P. , Kleinman Peter J. A. , Sharpley Andrew N. , Allen Arthur L.
Published: October 2009

Drainage ditches are a key conduit of nitrogen (N) from agricultural fields to surface water. The effect of ditch dredging, a common practice to improve drainage, on the fate of N in ditch effluent is not well understood. This study evaluated the effect of dredging on N transport in drainage ditches of the Delmarva Peninsula. Sediments from two ditches draining a single field were collected (0–5 cm) to represent conditions before and after dredging. Sediments were packed in 10‐m‐long recirculating flumes and subjected to a three‐phase experiment to assess the sediment's role as a sink or source of ammonium (NH4) and nitrate (NO3). Under conditions of low initial NH4–N and NO3–N concentrations in flume water, sediment from the undredged ditch released 113 times more NO3–N to water than did sediment from the dredged ditch. When flume water was spiked with NH4–N and NO3–N to simulate increases in N concentrations from drainage and runoff from adjacent fields, NO3–N in flume water increased during 48 h compared with the initial spiked concentration, while NH4–N decreased. These simultaneous changes were attributed to nitrification, with 23% more NO3–N observed in flume water with undredged ditch sediment compared with dredged ditch sediment. Replacing the N‐spiked water with deionized water resulted in two times more NO3–N released from the undredged ditch sediment than the dredged ditch sediment. These results suggest that ditch sediments could represent significant stores of N and that dredging could greatly affect the ditch sediment's ability to temporarily assimilate N input from field drainage.
Estimation of Indirect Nitrous Oxide Emissions from a Shallow Aquifer in Northern Germany
Authors: von der Heide Carolin , Böttcher Jürgen , Deurer Markus , Duijnisveld Wilhelmus H.M. , Weymann Daniel , Well Reinhard
Published: October 2009

Ground water is considered to be an important source for indirect N2O emissions. We investigated indirect N2O emissions from a shallow aquifer in Germany over a 1‐yr period. Because N2O accumulated in considerable amounts in the surface ground water (mean, 52.86 μg N2O–N L−1) and corresponding fluxes were high (up to 34 μg N2O–N m−2 h−1), it was hypothesized that significant indirect N2O emissions would occur via the vertical and the lateral emission pathway. Vertical N2O emissions were investigated by measuring N2O concentrations and calculating fluxes from the surface ground water to the unsaturated zone and at the soil surface. Lateral N2O fluxes were investigated by measuring ground water N2O and NO3− concentrations at five multilevel wells and at a waterworks well. Negligible amounts of N2O were emitted vertically into the unsaturated zone; most of it was convectively transported into the deeper autotrophic denitrification zone. Only a ground water level fall and rise triggered the emission of N2O (up to 3 μg N2O–N m−2 h−1) into the unsaturated zone. Ground water–derived N2O was probably reduced during the upward diffusion, and soil surface emissions were governed by topsoil processes. Along the lateral pathway, N2O and NO3− concentrations decreased with increasing depth in the aquifer. Discharging ground water was almost free of N2O and NO3−, and indirect N2O emissions were small.
Algal‐available Phosphorus Entering the Gulf of Finland as Estimated by Algal Assays and Chemical Analyses
Authors: Ekholm Petri , Rita Hannu , Pitkänen Heikki , Rantanen Pirjo , Pekkarinen Jouko , Münster Uwe
Published: October 2009

Algal‐available phosphorus (Paa) in river water and wastewater entering the Gulf of Finland (a Baltic Sea sub‐basin) was estimated by a fresh‐water and a brackish‐water modification of the dual‐culture algal assay. The assay results were further related to those obtained by routine chemical analyses. According to the brackish‐water assay, an average of 44% (range, 9–88%) of total phosphorus (TP) in water samples from the Neva, Kymijoki, and Narva rivers consisted of Paa, whereas the mean value given by the fresh‐water assay was 22% (range, 0–48%). Phaeodactylum tricornutum Bohlin, which was used as the test alga in the brackish‐water assay, had higher phosphoesterase activity and P affinity than did Pseudokirchneriella subcapitata Korschikov, which was used in the fresh‐water assay. This difference may explain the higher values of Paa shown by the brackish‐water assay. Of the analytical P forms, total dissolved P best approximated, yet underestimated, the Paa in river water samples. As for the biologically purified wastewaters of the city of St. Petersburg, both assays suggested that about 80% of TP (range, 59–103%) was available. That the assays gave similar results was probably due to the fact that most of the P in the wastewater samples was in the form of readily available dissolved reactive P. In untreated urban wastewaters, the mean proportion of Paa in TP was 46% (range, 19–76%). Although the true Paa may not be obtained by any assay, our findings corroborate the view that severe underestimation may occur if the test conditions are suboptimal for the release and uptake of P.
Modifying the Surface Charge of Pathogen‐Sized Microspheres for Studying Pathogen Transport in Groundwater
Authors: Pang L. , Nowostawska U. , Ryan J. N. , Williamson W. M. , Walshe G. , Hunter K. A.
Published: October 2009

Consuming pathogen‐contaminated groundwater has caused many waterborne disease worldwide. Microspheres are often used as pathogen surrogates because they can be made similar to pathogens in terms of their sizes, buoyant densities, and shapes. Laboratory studies have, however, shown that the surface charges of microspheres are very different from those of pathogens of comparable sizes, and that their attenuation and transport behaviors differ significantly to those of the pathogens mimicked. Thus, for microspheres to be better surrogates, their surface charges need to be modified. We have demonstrated that the surface charge of a microorganism can be closely mimicked by microspheres covalently coated with a protein that has a similar pHPZC to the microorganism. Using MS2 bacteriophage to test our concept, 20 nm carboxylated microspheres were covalently coated with casein. Zeta potentials as a function of pH were determined for purified MS2, casein, and uncoated and coated microspheres. The uncoated microspheres were significantly more negatively charged than MS2. The coated microspheres displayed zeta potentials and a pHPZC value similar to MS2. The modified surface charge on the microspheres was stable for at least 4 mo. Using the concept developed from this study, surrogates for many specific pathogens of concern can be developed, and the results can be corrected with pathogen die‐off determined independently in the laboratory. Protein‐coated microspheres could provide a new and alternative approach to investigate pathogen transport in groundwater. Future research is required to validate the surrogates' resemblances to pathogens in terms of their attenuation and transport behaviors in groundwater.
Antibiotic Resistant Bacterial Profiles of Anaerobic Swine Lagoon Effluent
Authors: Brooks J. P. , McLaughlin M. R.
Published: October 2009

Although land application of swine (Sus scrofa) manure lagoon effluent is a common and effective method of disposal, the presence of antibiotic‐resistant bacteria, both pathogenic and commensal can complicate already understood issues associated with its safe disposal. The aim of this study was to assess antibiotic resistance in swine lagoon bacteria from sow, nursery, and finisher farms in the southeastern United States. Effluents from 37 lagoons were assayed for the presence of Escherichia coli, Campylobacter, Listeria, and Salmonella Antibiotic resistance profiles were determined by the Kirby‐Bauer swab method for 12 antibiotics comprising eight classes. Statistical analyses indicated that farm type influenced the amount and type of resistance, with nurseries and sow farms ranking as most influential, perhaps due to use of more antibiotic treatments. Finisher farms tended to have the least amount of antibiotic class resistance, signaling an overall healthier market pig, and less therapeutic or prophylactic antibiotic use. Many bacterial isolates were resistant to penicillin, cephalosporin, and tetracycline class antibiotics, while nearly all were susceptible to quinolone antibiotics. It appeared that swine farm type had a significant association with the amount of resistance associated with bacterial genera sampled from the lagoons; nurseries contributed the largest amount of bacterial resistance.
Assessing Selenium Contamination in the Irrigated Stream–Aquifer System of the Arkansas River, Colorado
Authors: Gates Timothy K. , Cody Brent M. , Donnelly Joseph P. , Herting Alexander W. , Bailey Ryan T. , Mueller Price Jennifer
Published: October 2009

Prudent interventions for reducing selenium (Se) in groundwater and streams within an irrigated river valley must be guided by a sound understanding of current field conditions. An emerging picture of the nature of Se contamination within the Lower Arkansas River Valley in Colorado is provided by data from a large number of groundwater and surface water sampling locations within two study regions along the river. Measurements show that dissolved Se concentrations in the river are about double the current Colorado Department of Public Health and Environment (CDPHE) chronic standard of 4.6 μg L−1 for aquatic habitat in the upstream region and exceed the standard by a factor of 2 to 4 in the downstream region. Groundwater concentrations average about 57.7 μg L−1 upstream and 33.0 μg L−1 downstream, indicating a large subsurface source for irrigation‐induced dissolution and mobilization of Se loads to the river and its tributaries. Inverse correlation was found between Se concentration and the distance to the closest identified shale in the direction upstream along the principal groundwater flow gradient. The data also exhibited, among other relationships, a moderate to strong correlation between dissolved Se and total dissolved solids in groundwater and surface water, a strong correlation with uranium in groundwater, and power relationships with nitrate in groundwater. The relationship to nitrate, derived primarily from N fertilizers, reveals the degree to which dissolved Se depends on oxidation and inhibited reduction due to denitrification and suggests that there are prospects for reducing dissolved Se through nitrate control. Current and future results from these ongoing studies will help provide a foundation for modeling and for the discovery of best management practices (BMPs) in irrigated agriculture that can diminish Se contamination.
Geographic Relatedness and Predictability of Escherichia coli along a Peninsular Beach Complex of Lake Michigan
Authors: Nevers Meredith B. , Shively Dawn A. , Kleinheinz Gregory T. , McDermott Colleen M. , Schuster William , Chomeau Vinni , Whitman Richard L.
Published: October 2009

To determine more accurately the real‐time concentration of fecal indicator bacteria (FIB) in beach water, predictive modeling has been applied in several locations around the Great Lakes to individual or small groups of similar beaches. Using 24 beaches in Door County, Wisconsin, we attempted to expand predictive models to multiple beaches of complex geography. We examined the importance of geographic location and independent variables and the consequential limitations for potential beach or beach group models. An analysis of Escherichia coli populations over 4 yr revealed a geographic gradient to the beaches, with mean E. coli concentrations decreasing with increasing distance from the city of Sturgeon Bay. Beaches grouped strongly by water type (lake, bay, Sturgeon Bay) and proximity to one another, followed by presence of a storm or creek outfall or amount of shoreline enclosure. Predictive models developed for beach groups commonly included wave height and cumulative 48‐h rainfall but generally explained little E. coli variation (adj. R2 = 0.19–0.36). Generally low concentrations of E. coli at the beaches influenced the effectiveness of model results presumably because of low signal‐to‐noise ratios and the rarity of elevated concentrations. Our results highlight the importance of the sensitivity of regressors and the need for careful methods evaluation. Despite the attractiveness of predictive models as an alternative beach monitoring approach, it is likely that FIB fluctuations at some beaches defy simple prediction approaches. Regional, multi‐beach, and individual beach predictive models should be explored alongside other techniques for improving monitoring reliability at Great Lakes beaches.
Quantifying the Transport of Energetic Materials in Unsaturated Sediments from Cracked Unexploded Ordnance
Authors: Lewis Jeffrey , Martel Richard , Trépanier Luc , Ampleman Guy , Thiboutot Sonia
Published: October 2009

Dissolved explosive species have been found in the groundwater under military training areas. These explosives are thought to originate from munitions although the mechanism of transport to the groundwater is poorly understood. This study was conducted to determine whether ruptured unexploded ordnance may be a viable source term for these explosives. The rupturing effect of one 81 mm‐mortar exploding in close proximity to another 81‐mm mortar was observed and the resulting contaminants were collected. These contaminants were then subjected to leaching experiments on repacked, jack drill compacted unsaturated sediment columns in a climate controlled laboratory. The mortars which were exposed to nearby explosions were shown to be susceptible to rupturing rather than sympathetically detonating under certain conditions. The ruptured mortars released up to 166 ± 2 g of pulverized explosive residues (largely Composition B) and the results from the subsequent leaching tests showed that this explosive residue is highly mobile in unsaturated sandy soil. Up to 4.45 ± 1.00 g of dissolved explosive contamination was transported through the unsaturated soil columns during the first year of infiltration. The results indicate the mass of transported explosive residue dissolved in the leachate was primarily caused by the preferential dissolution of explosive contaminants having a grain size under 0.125 mm. Surface or near‐surface unexploded ordnance (UXO) on live fire ranges may therefore be significant sources of explosive environmental contamination after they have been exposed to other rounds which explode nearby.
Malate Exudation by Six Aerobic Rice Genotypes Varying in Zinc Uptake Efficiency
Authors: Gao Xiaopeng , Zhang Fusuo , Hoffland Ellis
Published: October 2009

Zinc (Zn) uptake by plant roots from soils low in plant‐available Zn may be increased by Zn‐mobilizing rhizosphere processes, including exudation of low‐molecular‐weight organic anions. A rhizotron experiment with a low Zn clay soil and a nutrient solution experiment were conducted to test if this occurs in six rice (Oryza sativa L.) genotypes varying in tolerance to low Zn supply. In both experiments, low Zn supply resulted in a marked decrease in biomass production of most genotypes compared with adequate Zn supply. The genotypes showed a significant variation in Zn efficiency. Plants responded to low Zn supply with increased root exudation of malate in both experiments. The malate concentration in the rhizosphere of three genotypes ranged from 0.22 to 0.59 mmol L−1 in rhizotron experiment, and the malate exudation rate of five genotypes ranged from 0.18 to 0.53 nmol g−1 root dw s−1 in the nutrient solution experiment. On average, low Zn supply in the rhizotron experiment increased rhizosphere malate concentration by 64% compared with that at adequate Zn supply. The averaged malate exudation rate at low Zn in the nutrient solution experiment was 40% greater than at adequate Zn supply. The malate exudation of rice genotypes at low Zn was not correlated to Zn efficiency or Zn uptake in either experiment. Based on a soil malate extraction experiment, the observed genotypic difference in rhizosphere malate concentration is expected to have a negligible effect on the concentration of Zn in soil solution. These findings suggest that Zn mobilization by rice genotypes cannot be explained by increased malate exudation alone, indicating that other mechanisms contribute to the variation in plant Zn uptake. The results also emphasize that effects of root exudates on soil properties need to be assessed to evaluate the role of root exudation in nutrient mobilization.
Pore Water Sampling in Acid Sulfate Soils: A New Peeper Method
Authors: Johnston Scott G. , Burton Edward D. , Keene Annabelle F. , Bush Richard T. , Sullivan Leigh A. , Isaacson Lloyd
Published: October 2009

This study describes the design, deployment, and application of a modified equilibration dialysis device (peeper) optimized for sampling pore waters in acid sulfate soils (ASS). The modified design overcomes the limitations of traditional‐style peepers, when sampling firm ASS materials over relatively large depth intervals. The new peeper device uses removable, individual cells of 25 mL volume housed in a 1.5 m long rigid, high‐density polyethylene rod. The rigid housing structure allows the device to be inserted directly into relatively firm soils without requiring a supporting frame. The use of removable cells eliminates the need for a large glove‐box after peeper retrieval, thus simplifying physical handling. Removable cells are easily maintained in an inert atmosphere during sample processing and the 25‐mL sample volume is sufficient for undertaking multiple analyses. A field evaluation of equilibration times indicates that 32 to 38 d of deployment was necessary. Overall, the modified method is simple and effective and well suited to acquisition and processing of redox‐sensitive pore water profiles > 1 m deep in acid sulfate soil or any other firm wetland soils.
Combined Effect of Surfactant and Ultrasound on Nano Calcium Carbonate Synthesized by Crystallization Process
Authors: Sonawane Shirish H , Gumfekar Sarang P , Meshram Satish , Deosarkar Manik P , Mahajan Chantrashekhar M , Khanna Pawan
Published: October 2009

This article presents ultrasound assisted carbonization method for the synthesis of calcium carbonate nanoparticles (nano calcite). The effect of different surfactants, such as polyacrylic acid, steric acid, sodium tripolyphosphate and myristic acid, on the synthesis of nano CaCO3 was investigated. Concentration of surfactants ranged from 0.2-1.0g/L. X-ray diffraction patterns (XRD) confirmed cubic structure of nano CaCO3 showing characteristic reflection of calcite phase. Transmission electron microscopy (TEM) images showed that the particles are cubical in nature. The use of an ultrasound probe during synthesis leads to narrow distribution of particles. The conductivity and pH value of reaction mixture was measured during the reaction. The time required for the completion of reaction changes with different surfactants was also found. The crystallite size was found to be dependent on surfactant concentration. The minimum time was noted for sodium tripolyphosphate which was 40 min. The crystallite size was found to increase as per the trail sequence of the surfactant, sodium tripolyphosphate, steric acid and polyacrylic acid, myristic acid. The myristic acid shows the biggest crystallite size due to its hydrophobic nature, while sodium tripolyphosphate plays an important role in crystal growth inhibition giving lower crystallite size. Finally, the results presented here demonstrate that nano-calcite crystals can be synthesized, for high potential industrial applications such as filler in the paper and polymer industry.