bluuebunny/crossref_metadata_2025 huggingface dataset:
Persistence of specific antibody response in different experimental infections of mice with Toxocara canis larvae
Authors: Chieffi Pedro Paulo , Peres Benedito A , Mello Elisabete O. de , Kanamura Herminia , Brandão Marcelo M.
Published: May 2006

Anti-Toxocara antibody production and persistence were studied in experimental infections of BALB/c mice, according to three different schedules: Group I (GI) - 25 mice infected with 200 T. canis eggs in a single dose; Group II (GII) 25 mice infected with 150 T. canis eggs given in three occasions, 50 in the 1st, 50 in the 5th and 50 in the 8th days; Group III (GIII) - 25 mice also infected with 150 T. canis eggs, in three 50 eggs portions given in the 1st, 14th and 28th days. A 15 mice control group (GIV) was maintained without infection. In the 30th, 50th, 60th, 75th, 105th and 180th post-infection days three mice of the GI, GII and GIII groups and two mice of the control group had been sacrificed and exsanguinated for sera obtention. In the 360th day the remainder mice of the four groups were, in the same way, killed and processed. The obtained sera were searched for the presence of anti-Toxocara antibodies by an ELISA technique, using T. canis larvae excretion-secretion antigen. In the GI and GII, but not in the GIII, anti-Toxocara antibodies had been found, at least, up to the 180th post-infection day. The GIII only showed anti-Toxocara antibodies, at significant level, in the 30th post-infection day.
Bancroftian filariasis in two urban areas of Recife, Brasil: the role of individual risk factors
Authors: Albuquerque M. de Fátima Militão de , Marzochi Mauro C , Ximenes Ricardo A. de A. , Braga M. Cintia , Silva M. C. Maia , Furtado André F
Published: May 2006

Bancroftian filariasis is spreading in towns of endemic areas as in Recife, northeastern Brazil, where it is a major public health problem. This paper deals with the prevalence of microfilaraemia and filarial disease in two urban areas of Recife, studying their association with individual characteristics and variables related to the exposure to the vectors. The parasitologic survey was performed through a "door-to-door" census and microfilaraemia was examined by the thick-drop technique using 45µl of peripheral blood collected between 20:00 and 24:00 o' clock. 2,863 individuals aged between 5 and 65 years were interviewed and submitted to clinical examination. Males aged between 15 and 44 years old presented the greatest risk of being microfilaraemic. Microfilaraemia was also significantly associated with no use of bednet to sleep. The risk of being microfilaraemic was greater among those who had lived in the studied areas for more than 5 years. The overall disease prevalence was 6.3%. Males presented the greatest risk of developing acute disease. The risk of developing chronic manifestations was also greater among males and increased with age. We found no association between time of residence, bednet use, microfilaraemia and acute and chronic disease. We may conclude that in endemic areas there are subgroups of individuals who has a higher risk of being microfilariae carriers due to different behaviours in relation to vector contact.
Bacterial antigen detection in cerebrospinal fluid by the latex agglutination test
Authors: Landgraf Ilka Maria , Alkmin Maria das Graças Adelino , Vieira Maria de Fátima Paiva
Published: May 2006

Eighty purulent cerebrospinal fluid (CSF) samples from patients with clinical evidence of meningitis were studied using the Directigen latex agglutination (LA) kit to determine the presence of bacterial antigen in CSF. The results showed a better diagnostic performance of the LA test than bacterioscopy by Gram stain, culture and counterimmunoelectrophoresis (CIE), as far as Neisseria meningitidis groups B and C, and Haemophilus influenzae type b are concerned, and a better performance than bacterioscopy and culture considering Streptococcus pneumoniae. Comparison of the results with those of culture showed that the LA test had the highest sensitivity for the Neisseria meningitidis group C. Comparing the results with those of CIE, the highest levels of sensitivity were detected for N. meningitidis groups B and C. Regarding specificity, fair values were obtained for all organisms tested. The degree of K agreement when the LA test was compared with CIE exhibited better K indices of agreement for N. meningitidis groups B and C.
Atributos físicos de um argissolo e rendimento de culturas de acordo com o revolvimento do solo em plantio direto
Authors: Marcolan Alaerto Luiz , Anghinoni Ibanor
Published: May 2006

O sistema plantio direto melhora a qualidade estrutural do solo. Entretanto, o tráfego de máquinas pode levar à compactação superficial. Nessa situação, a mobilização para incorporar calcário, ao mesmo tempo que corrige a acidez na camada mobilizada do solo, reduz os possíveis efeitos negativos da compactação. Assim, avaliaram-se os efeitos de mobilizar ou não o solo por ocasião das reaplicações de calcário nos atributos físicos no perfil do solo e no rendimento de culturas em diferentes sistemas e tempos de manejo do solo. O experimento foi realizado na Estação Experimental Agronômica da UFRGS, em Eldorado do Sul (RS), em um Argissolo Vermelho distrófico típico. Os manejos foram: (a) sistema plantio direto 12 anos, (b) sistema plantio direto oito anos, (c) sistema plantio direto com mobilização do solo para incorporar calcário a cada quatro anos e (d) preparo convencional 12 anos. Quatro anos após a mobilização do solo para a segunda reaplicação de calcário, foram determinados a densidade, a porosidade total, a macroporosidade, a microporosidade, a estabilidade de agregados e o teor de carbono orgânico em três camadas (0,0-2,5; 2,5-7,5 e 7,5-15,0 cm) do solo, bem como a produtividade das culturas de milho e aveia + ervilhaca. O solo já havia recuperado os atributos físicos à condição original após quatro anos de plantio direto. Os atributos físicos do solo foram mais uniformes no perfil no preparo convencional, mas a estabilidade de agregados na camada superficial foi menor em relação ao plantio direto. As diferenças nos atributos físicos do solo decorrentes dos sistemas de manejo não foram suficientes para influir na produtividade das culturas de milho e de aveia + ervilhaca.
Problematização como estratégia de educação nutricional com adolescentes obesos
Authors: Rodrigues Érika Marafon , Boog Maria Cristina Faber
Published: May 2006

Obesidade é um problema de saúde pública em cuja etiologia determinantes sociais têm relevância, sendo que intervenções com adolescentes encontram condição biopsicossocial complexa. A pesquisa avaliou intervenção de educação nutricional, empregando o método da problematização, com 22 adolescentes obesos, atendidos coletiva e individualmente, durante oito meses. Falas foram coletadas mediante emprego de tarjetas, registro por observador e gravação. O método foi qualitativo e a técnica, a análise de conteúdo. A problematização mostrou-se instrumento facilitador para mudança de comportamento alimentar, fazendo emergir reflexões sobre: práticas alimentares, contexto familiar, estigma social, relacionamento com profissionais de saúde, religiosidade. Os adolescentes em atendimento individual problematizaram com mais efetividade práticas alimentares, enquanto no coletivo houve maior problematização dos aspectos familiares e psicológicos, com efetivas mudanças qualitativas na alimentação de ambos os grupos. Concluiu-se que a intervenção foi eficaz para ajudar os adolescentes a compreenderem sua história de vida e determinantes do comportamento alimentar, efetivarem mudanças na sua alimentação espontaneamente, conscientizarem-se das possibilidades de perpetuação da mudança das práticas alimentares e exercerem com autonomia o papel de sujeitos no cuidado à saúde.
Confiabilidade do diagnóstico final de dengue na epidemia 2001-2002 no Município do Rio de Janeiro, Brasil
Authors: Toledo Ana Lucia Araujo de , Escosteguy Claudia Caminha , Medronho Roberto de Andrade , Andrade Flávia Coutinho de
Published: May 2006

Este estudo analisou a confiabilidade do diagnóstico final das 155.242 notificações de dengue da epidemia 2001-2002 no Município do Rio de Janeiro, fornecidas pela Secretaria Municipal de Saúde do Rio de Janeiro, por meio do Sistema de Informação de Agravos de Notificação (SINAN). O diagnóstico final possui como opções de preenchimento: dengue clássico, febre hemorrágica do dengue, descartado, inconclusivo e ignorado. Foi construída uma rotina em Epi Info para comparar o diagnóstico final digitado no SINAN com os critérios do Ministério da Saúde (MS), agrupando os casos como dengue clássico, dengue hemorrágico, descartado e inconclusivo (inclui ignorado). O diagnóstico final mostrou 52,4% dengue clássico, 0,6% dengue hemorrágico, 0,9% descartado e 46% de inconclusivo e ignorado, sendo que 78% de dengue clássico, 69% de dengue hemorrágico e 21,1% dos descartados preencheram os critérios do MS. A confiabilidade do diagnóstico final digitado foi em geral satisfatória (kappa = 0,681; IC95%: 0,685-0,677), porém baixa para os óbitos (kappa = 0,152; IC95%: 0,046-0,258). Considerando-se o volume da epidemia, o diagnóstico final de dengue clássico e dengue hemorrágico foi satisfatório, porém a alta proporção de casos ignorados e inconclusivos e a baixa qualidade da informação nos óbitos limitam o uso do SINAN nesse contexto.
O recrutamento da elite, as mudanças na composição social e a 'crise da medicina' no Rio Grande do Sul
Authors: Coradini Odaci Luiz
Published: May 2006

Este artigo tem três objetivos. O primeiro deles apresenta um quadro geral do processo de formação e institucionalização do ensino da medicina e do exercício da profissão médica no Rio Grande do Sul, levando em conta os princípios e critérios de excelência profissional e social vigentes e da hierarquia e recrutamento de sua elite. O segundo busca apresentar as principais mudanças na composição social do corpo docente, desde sua formação. O terceiro discute alguns fundamentos da chamada 'crise da medicina'.
Destruição e proteção da Mata Atlântica no Rio de Janeiro: ensaio bibliográfico acerca da eco-história
Authors: Soffiati Arthur
Published: May 2006

A partir da análise crítica do livro de José Augusto Drummond, Devastação e preservação ambiental no Rio de Janeiro, o autor faz um inventário dos investigadores, das questões e das fontes que configuram a eco-história, um campo recente de investigação que agora começa a aflorar na historiografia brasileira, obrigando-a a repensar em profundidade as relações entre ciências sociais e naturais, sociedade e biologia, homem e natureza.
Célula de carga de impacto na caracterização de materiais para a cominuição. Parte 1: calibração
Authors: Tavares Luís Marcelo M. , Lima Alfredo da Silva
Published: May 2006

Nas últimas décadas, tem crescido, de forma significativa, a utilização de informações fundamentais de fratura de partículas, na modelagem e simulação de processos de cominuição, na indústria. Entre os equipamentos utilizados, na avaliação do comportamento mecânico de partículas, se destaca a célula de carga de impacto. Ela é um híbrido entre o aparelho de queda de peso e a barra dividida de Hopkinson e permite a medida da curva força-deformação resultante do impacto de partículas individuais ou de leitos de partículas sob condições de carregamento rápido. Células de carga de impacto com diferentes diâmetros foram projetadas e construídas na COPPE/UFRJ, permitindo a caracterização da fratura de partículas dentro de um intervalo amplo de tamanhos e energias aplicadas. Essa primeira parte do artigo descreve o funcionamento do aparelho e a sua calibração, realizada a partir de princípios da propagação de ondas longitudinais em barras e da teoria de contatos de Hertz.
Feeding dynamics and ecomorphology of Oligosarcus jenynsii (Gunther, 1864) and Oligosarcus robustus (Menezes, 1969) in the Lagoa Fortaleza, southern Brazil
Authors: Nunes D. M. , Hartz S. M.
Published: May 2006

Oligosarcus jenynsii and Oligosarcus robustus are fishes of Characidae family that occur in Rio Grande do Sul, Uruguay and northern Argentina. This work purported to study the feeding dynamics (repletion and hepatosomatic indexes and condition factor) over time, and to investigate the coexistence of these two species by evaluating the partition of resources using qualitative and quantitative analyses of diet, temporal and spatial segregation throughout the water column and some ecomorphological aspects of the species in the Lagoa Fortaleza. Specimens were sampled monthly, from May 2000 to April 2001 during 24 h/month, using stationary gill nets of different mesh sizes. The records of each individual included total and standard length; total, stomach and liver weight; sex and stomach repletion. The variation of the mean values of repletion index and relative frequencies of stomach repletion stages indicate that O. jenynsii and O. robustus do not present seasonal differences in feeding intensity. The hepatosomatic index shows an allocation of energy to the liver during every period except reproduction, when part of the energy is used for gonad maturation. The estimated condition factor for both species reveals an increase in the reproductive period, evidencing the influence of gonads upon the condition of the fish. The diet analysis revealed that O. robustus is piscivorous, whereas O. jenynsii is a generalist carnivore, tending to piscivory as well. The active period of O. robustus is more concentrated at sunrise and sunset, whereas O. jenynsii is continually active, a characteristic related to hunting for prey. The ecomorphological analysis revealed differences between the two species in the dimensions of the mouth. Evidence suggests that the species coexist, sharing food sources, differing in oral morphology but ingesting similar prey, possibly because food is not a limiting factor in the environment.
Considerations on the effect of anti-sandfly antibodies on biological parameters of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae)
Authors: Vilela M. L. , Souza N. A. , Oliveira S. M. P. , Costa-Pinto D. , Cabello P. H. , Rangel E. F. , Traub-Cseko Y. M.
Published: May 2006

The immunization of vertebrate hosts with vector components may be an alternative for the control of diseases transmitted by insects. In the present study we evaluated the effects of anti-sandfly antibodies on some of the biological parameters of female Lutzomyia longipalpis, a vector of visceral leishmaniasis. Rabbits were immunized with extracts of gut from blood-fed (GB) or sugar-fed (GS) females, carcass of sugar-fed (CS) or blood-fed (CB) females, and with repeated sandfly bites (BITE). Immune sera showed increased antibody titers compared to pre-immunized animals, and specific bands were detected by Western Blot. An analysis of biological parameters revealed a decline in fecundity in the group of females fed on rabbits immunized with GB and BITE. Longevity and mortality were studied in females with oviposition (parous) and without oviposition (nulliparous). Nulliparous females that fed on rabbits immunized with bites died in the highest percentage. A mortality analysis after egg laying revealed a peak on the fifth day in all the groups, but females fed on rabbit subjected to repeated bites showed a shift towards the third day.
Complicações no tratamento com laser endovascular em varizes de membros inferiores
Authors: Soracco Jorge Enrique , D'Ámbola Jorge Lopez , Ciucci José Luis , Godoy José Maria Pereira de , Belczak Cleusa Ema Quilici
Published: May 2006

OBJETIVO: O objetivo do presente estudo é relatar as complicações no tratamento de varizes em membros inferiores com laser endovascular. MÉTODOS: Foram levantadas, no período de junho de 1999 a dezembro de 2002, algumas complicações, como queimadura de pele, neurite do nervo safeno, hiperpigmentação e fibrose no local da safena em 250 pacientes submetidos a tratamento endovascular com laser em varizes de membros inferiores. O diagnóstico das complicações foi clínico e baseado nos sinais e sintomas. Avaliou-se 196 pacientes do sexo feminino e 54 do sexo masculino, com idades variando entre 25 e 79 anos, no Hospital Militar de Buenos Aires. Foram tratados com laser de diodo de alta potência de 810 nm de longitude de onda mediante um sistema de fibras óticas semi-rígidas de quartzo de 400 e 600 µm e ponta de contato plana em modo cirúrgico contínuo. Para análise estatística, foram calculadas as percentagens. RESULTADOS: Lesões tipo queimadura foram observadas em 3,2%, hiperpigmentação em 9,6%, fibrose no local da safena por mais de 6 meses em 5,6% e neurite do nervo safeno em 4,8%. CONCLUSÃO: Conclui-se que o tratamento com laser endovascular de varizes de membros inferiores não é desprovido de intercorrências e que os fatores que levaram a essas complicações devem ser identificados e reavaliados.
Resultados tardios das reconstruções arteriais dos membros inferiores com a utilização de veias portadoras de dilatações varicosas revestidas seletivamente com segmentos protéticos
Authors: Mellière Didier , Albuquerque Maria Claudia de , Desgranges Pascal , Allaire Eric , Becquemin Jean Pierre
Published: May 2006

OBJETIVO: Responder as seguintes questões: 1) o revestimento protético deve ser precedido de uma redução da ectasia? 2) as zonas revestidas apresentam um risco de hiperplasia ou estenose? 3) as zonas não revestidas possuem um risco de dilatação e ruptura? MÉTODOS: Doze pacientes (10 homens e duas mulheres), com idades entre 33 e 77 anos (idade mediana = 68), foram submetidos a pontes em conseqüência de arterite (n = 7), aneurisma poplíteo (n = 4) ou ruptura de prótese (n = 1). As pontes foram fêmoro-poplíteas (n = 8), fêmoro-infra poplíteas (n = 3) e poplíteo-poplítea (n = 1). A safena utilizada foi de forma reversa em nove casos e ex situ devalvuladas em três casos. Os revestimentos foram aplicados em número de um (n = 2), dois (n = 3), três (n = 6) e quatro (n = 1). Todos, exceto um, foram de PTFE. RESULTADOS: Duas pontes ocluíram, uma precocemente por déficit de leito distal e outra 4 anos após a operação. As outras 10 pontes permaneceram pérvias durante o acompanhamento, que variou entre 1 e 11 anos (mediana = 4 anos). Metade dos casos apresentou uma deterioração progressiva do leito distal. No último controle, duas pontes permaneceram pérvias, a despeito de um leito distal desértico. CONCLUSÃO: Os resultados desta série apresentam-se notadamente superiores aos das pontes protéicas descritas na literatura. O revestimento é efetuado facilmente com uma prótese curta de PTFE de parede fina. É inútil reduzir as dilatações antes do revestimento por sutura ou ressecção - anastomose. As zonas situadas sobre a bainha de PTFE não evoluem para estenoses. As zonas intermediárias dilatam-se por vezes moderadamente e sem risco de ruptura.
Subepithelial Connective Tissue Grafts in the Treatment of Multiple Recession‐Type Defects
Authors: Chambrone Luiz Armando , Chambrone Leandro
Published: May 2006

Background: There is little documentation regarding the treatment of multiple recession‐type defects. The objective of this study was to evaluate the results obtained with a connective tissue graft placed under a coronally advanced flap for the treatment of multiple gingival recessions.

Methods: Twenty‐eight patients, with at least two recession defects affecting adjacent teeth, were treated with a combination of a connective tissue graft and a coronally advanced flap. At baseline, the following measurements were recorded: 1) recession depth; 2) probing depth; 3) clinical attachment level; and 4) width of keratinized tissue. At 6 months post‐surgery, all clinical measurements were repeated.

Results: The mean root coverage from baseline to 6 months post‐surgery results was 96%. Complete root coverage was achieved in 20 (71%) of the 28 defects. The mean recession depth decreased from 3.84 ± 1.50 mm to 0.14 ± 0.23 mm. Statistically significant improvements were found for all clinical parameters from baseline to 6 months (P <0.01). Patients with maxillary recessions recorded statistically superior outcomes than patients with mandibular recessions.

Conclusions: The results of the present study demonstrated that the connective tissue graft associated with a coronally advance flap is an effective procedure to cover multiple gingival recessions, especially in defects localized in the maxillary arch. However, further investigation focusing on the effects of this root coverage procedure in mandibular sites is necessary.
The Effect of Varying the Particle Size of Beta Tricalcium Phosphate Carrier of Recombinant Human Bone Morphogenetic Protein‐4 on Bone Formation in Rat Calvarial Defects
Authors: Jung Ui‐Won , Choi Seong‐Yong , Pang Eun‐Kyoung , Kim Chang‐Sung , Choi Seong‐Ho , Cho Kyoo‐Sung
Published: May 2006

Background: Beta tricalcium phosphate (β‐TCP) has been developed as one of the carriers of recombinant human bone morphogenetic protein (rhBMP). However, it is not known whether the particle size of β‐TCP is related to its resorption rate and the degree of bone formation. The purpose of this study was to evaluate the effect of using β‐TCP with different particle sizes on the ability of rhBMP‐4 to enhance bone formation in the rat calvarial defect model.

Methods: Calvarial, 8‐mm‐diameter, critical‐size defects were created in 100 male Sprague‐Dawley rats. Five groups of 20 animals each received either rhBMP‐4 (2.5 μg) using β‐TCP with a particle size of 50 to 150 μm, rhBMP‐4 (2.5 μg) using β‐TCP with a particle size of 150 to 500 μm, a β‐TCP control with a particle size of 50 to 150 μm, a β‐TCP control with a particle size of 150 to 500 μm, or a sham‐surgery control, respectively, and were evaluated by measuring their histologic and histometric parameters following a 2‐ and 8‐week healing interval.

Results: There were no significant differences in the defect closure, new bone area, or augmented area between either the two rhBMP‐4/β‐TCP groups or between the two β‐TCP control groups at 2 and 8 weeks.

Conclusions: rhBMP‐4 combined with either small‐ or large‐particle β‐TCP had a significant effect on the induction of bone formation compared to either a small‐ or large‐particle β‐TCP control or a sham‐surgery control. Within the parameters of this study, varying the particle size of β‐TCP did not seem to have a significant effect on bone formation.
Alfalfa as an Alternative to Bermudagrass for Pastured Stocker Cattle Systems in the Southern USA
Authors: Cassida K. A. , Stewart C. B. , Haby V. A. , Gunter S. A.
Published: May 2006

Alfalfa (Medicago sativa L.) may support better stocker calf gains than common bermudagrass [Cynodon dactylis (L.) Pers.] in the southern USA. Yearling heifers (Bos taurus × B. indicus) grazed each type of pasture for 2 yr on a Coastal Plain soil in southwest Arkansas. Alfalfa stand counts declined linearly with time after planting. Spring forage mass was greater for alfalfa than bermudagrass, but summer dormancy of alfalfa resulted in a summer forage mass advantage for bermudagrass. Bermudagrass provided a longer grazing season (115–168 d for bermudagrass vs. 66–156 d for alfalfa, P < 0.01), more animal grazing days (1040–1452 vs. 594–1221 d, P < 0.01), and fewer grazing interruptions than alfalfa. Average daily gain (ADG, 462 vs. 319 g d−1, P < 0.05) and total liveweight gain (664 vs. 447 kg ha−1, P < 0.05) were greater for alfalfa than bermudagrass in Year 2. In both years, heifers grazing alfalfa made the same amount of liveweight gain in less time than heifers grazing bermudagrass. The bermudagrass system had a negative net return across the trial period. Net return for the alfalfa system was dependent on the value of harvested hay. When alfalfa hay value reached $95 Mg−1 of dry matter (DM), net return was greater for the alfalfa system than for the bermudagrass system ($59 vs. $−148 ha−1, P < 0.05). On a Coastal Plain soil, renovation of common bermudagrass to alfalfa pasture can be economically feasible under a dual stocker/hay production system.
Crushed Cotton Gin Compost Effects on Soil Biological Properties, Nutrient Leaching Losses, and Maize Yield
Authors: Tejada M. , Gonzalez J. L.
Published: May 2006

There is currently interest in the use of industrial by‐products to reduce the use of synthetic fertilizers; however, most organic wastes contain relatively low N levels. Our objectives were to: (i) determine the effect of incorporating crushed cotton gin compost, with and without inorganic fertilizers, on soil biological properties during three maize crops (Zea mays L., cv. Tundra); (ii) study nutrient leaching losses from soils receiving these fertilizer treatments; and (iii) to evaluate the effect of these fertilizer treatments on nutrition and yield of a maize crop. Compost was applied at 0, 20, and 40 t ha−1 rates with and without 400 kg N ha−1 (as NH4NO3), 80 kg P ha−1 [as (NH4)H2PO4], and 120 kg K ha−1 (as K2SO4) on a Typic Xerofluvent located near Sevilla (Andalusia, Spain) for 3 yr. At the end of the study, soil microbial biomass was 32% higher in the treatment including inorganic fertilizer than in the compost‐only treatment. Soil biochemical properties were greater in the fertilizer treatment than the compost‐only treatment (by 61, 50, 36, and 32% for dehydrogenase, N‐α‐benzoyl‐L‐argininamide protease, arylsulfatase, and phosphatase activities). Macronutrient losses were greatest in the treatment including inorganic fertilizer, where increases of 24% for inorganic N, 31% for P, and 18.5% for K over the compost treatment were noted. Lowest N/P ratios were produced by the treatment including inorganic fertilizer, which suggest a lower eutrophication risk in drainage waters from soils treated with this fertilizer. The mineral nutrition, grain protein, and maize yield indicate that the compost plus inorganic fertilizer is adequate and has a good potential for use.
Carrying Capacity, Utilization, and Weathering of Swathed Whole Plant Barley
Authors: Baron V. S. , Dick A. C. , McCartney D. , Basarab J. A. , Okine E. K.
Published: May 2006

Winter grazing of swathed whole‐plant small grain crops can reduce costs for beef producers, but little is known about levels of carrying capacity, utilization and weathering losses of nutritive value and their year‐to‐year variability. The objective of the present study was to determine carrying capacity, utilization and weathering losses to nutritive value in relation to beef cow (Bos taurus) requirements during winter grazing of swathed whole‐plant spring barley (Hordeum vulgare L.) in a field‐scale trial. Pregnant beef cows (685 kg wt.) limit‐grazed swathed whole‐plant barley (November–February, 1997–2001) at daily available forage levels approximating 2% of body weight at Lacombe, AB. Carrying capacity was affected by barley yield, utilization rate, and average daily dry matter consumption. Carrying capacities ranged from 481 to 879 cow‐d ha−1, utilization from 75.5 to 92% and daily dry matter consumption rates ranged from 8.6 to 12.9 kg cow‐d−1. Weathering losses of nutritive value, as indicated by the difference between that of the standing crop and the mean of grazing season swath, were slight compared to a much larger difference between grazing season swath and residue. Generally, the nutritive requirements for maintenance of beef cows (NRC, 1996) could be readily met by swathed barley.
Nitrogen Fertility and Planting Date Effects on Lint Yield and Cry1Ac (Bt) Endotoxin Production
Authors: Pettigrew W. T. , Adamczyk J. J.
Published: May 2006

Early planted cotton (Gossypium hirsutum L.) and varieties expressing the Bacillus thuringiensis (Bt) gene offer improved yield potential. It is not clear whether the current N recommendations remain appropriate for these new production options. The objectives were to determine how varying rates, application timing, and sources of N affected cotton dry matter partitioning, leaf chlorophyll (Chl) concentration, leaf Bt (Cry1Ac) endotoxin concentration, lint yield, and fiber quality. Four N treatments (112 kg N ha−1 anhydrous; 112 kg N ha−1 liquid; 112/56 kg N ha−1 split; 56/56 kg N ha−1 split) were applied to three cotton varieties (PM 1218BR, STV 4691B, and FM 832) planted on either an early or normal planting date from 2001 through 2004. The N response was consistent across planting dates and varieties for all data collected as shown by the lack of any interactions with these variables. Although N treatments had no effect on lint yield or any dry matter partitioning components, plants receiving the 112/56 kg N ha−1 split application treatment exhibited 14% greater leaf Cry1Ac concentration and a 3% greater leaf Chl concentration than the other N treatments. Early planted cotton had 5% greater leaf Chl concentration but a 12% lower leaf Cry1Ac concentration than normal planted cotton. Lower Cry1Ac levels may reflect enhanced remobilization of the leaf protein to feed the faster developing boll load of the early planted cotton. Early planted cotton yielded 10% more than normal planted cotton because it produced 9% more bolls. Current N recommendations for normal planted cotton also appear sufficient for early planted cotton.
Effects of Standards-Based Mathematics Education: A Study of the Core-Plus Mathematics Project Algebra and Functions Strand
Authors: Huntley Mary Ann , Rasmussen Chris L. , Villarubi Roberto S. , Sangtong Jaruwan , Fey James T.
Published: May 2006

To test the vision of Standards–based mathematics education, we conducted a comparative study of the effects of the Core-Plus Mathematics Project (CPMP) curriculum and more conventional curricula on growth of student understanding, skill, and problem-solving ability in algebra. Results indicate that the CPMP curriculum is more effective than conventional curricula in developing student ability to solve algebraic problems when those problems are presented in realistic contexts and when students are allowed to use graphing calculators. Conventional curricula are more effective than the CPMP curriculum in developing student skills in manipulation of symbolic expressions in algebra when those expressions are presented free of application context and when students are not allowed to use graphing calculators.
Enhancement of Phosphorescence by Surface‐Plasmon Resonances in Colloidal Metal Nanoparticles: The Role of Aggregates
Authors: Ostrowski J. C. , Mikhailovsky A. , Bussian D. A. , Summers M. A. , Buratto S. K. , Bazan G. C.
Published: May 2006

The spectroscopic and near‐field scanning optical microscopy (NSOM) studies of phosphorescent films doped with colloidal gold nanoparticles (NPs) are presented. Films with a high concentration of 2,3,7,8,12,13,17,18‐octaethyl‐21H,23H‐porphine platinum(II) dispersed in a neutral polymer poly[(methyl methacrylate)‐co‐(ethyl acrylate)] demonstrate a twofold increase of the phosphorescence quantum yield after the addition of aggregated NPs. In materials doped with unaggregated particles, a decrease of the emission yield is observed. Theoretical modeling of the phosphorescence transients suggests a minimization of the triplet–triplet quenching owing to the presence of fast processes that decrease the concentration of chromophores in the excited state and may be both of radiative and non‐radiative origin. NSOM examination of the films reveals increased light emission around large NP clusters. This observation demonstrates significant enhancement of the spontaneous emission rates by the large aggregates, although unaggregated NPs introduce mostly phosphorescence quenching sites.
Smart Microfluidic Channels
Authors: Ionov L. , Houbenov N. , Sidorenko A. , Stamm M. , Minko S.
Published: May 2006

The walls of microfludic “smart channels” are coated by responsive mixed polymer brushes with a gradient of chemical composition. The concept of the smart channels is based on switching/adaptive behavior of the mixed polymer brushes where wetting and nonwetting can be tuned upon interaction with liquids. This design of microfluidic channels brings new opportunities for manipulating the passage of liquids in the channels. The developed approach allows us to fabricate three microfluidic elements for separation, sensing, selection, and dosing microvolumes of liquids.
Does morphology stick? Tailored particle morphologies by swelling polymerization process
Authors: Kirsch S. , Kutschera M. , Choi N.‐Y. , Frechen T.
Published: May 2006

Structured dispersion particles suitable for pressure sensitive adhesives (PSA) were synthesized via swelling polymerization technique (EP 359562). Particles consisting of poly(n‐butyl acrylate) copolymerized with different types of carboxylic acids were used as seeds. The final particles were synthesized by swelling polymerization process, using 6 wt % styrene or 6 wt % methyl methacylate. The resulting particle morphology was analyzed by atomic force microscopy (AFM) and transmission electron microscopy (TEM). From previous works (Coll Surf A 2001, 183–185, 725–737; J Appl Polym Sci 2004, 91, 2610–2623) where two‐step emulsion polymerization was used on similar particles, it is expected that the particle morphology is affected by the polarity of the monomer used for swelling polymerization because of the phase compatibility (thermodynamic parameter). In this work, the seed particles used were always of a glass transition temperature (Tg) below polymerization temperature. The diffusion of the growing polymer chains from the swelling polymerization is therefore mainly affected by their own Tg and the influence of the carboxy groups on the chain length of the entering radicals (kinetic parameter). The different morphologies of the single particles are discussed qualitatively. The effects of reaction parameters are compared with the results given in the previous work. The structure of the corresponding dispersion films was characterized using AFM. Correlations to macroscopic properties such as the cohesive strength and peel adhesion to different substrates are discussed. The results are also compared with the application properties of the corresponding unmodified particles, statistical copolymers, and to blends with small sized PMMA or PS particles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1444–1455, 2006
Preparation of bimodal polypropylene in two‐step polymerization
Authors: Abedi S. , Hassanpour N.
Published: May 2006

Polymerization of propylene was carried out by using MgCl2.EtOH.TiCl4.DIBP.TEA.cHMDMS catalyst system in n‐heptane, where MgCl2, EtOH, TiCl4, DIBP (diisobutyl phthalate), TEA (triethyl aluminum), and cHMDMS (cyclohexyl methyl dimethoxy silane) were support, ethanol for alcoholation, catalyst, external donor, cocatalyst (activator), and internal donor, respectively. The catalyst activity and polymer isotacticity were studied by measuring the produced polymer and its solubility in boiling n‐heptane, respectively. The molecular weight and molecular weight distribution of the polymers were evaluated by gel permeation chromatography. Hydrogen was used for controlling the molecular weight. For producing the bimodal polypropylene, the polymerization was carried out in two steps (i.e., in the presence and absence of hydrogen). It was found that the catalyst showed high activity and stereoselectivity, on the other hand, bimodal polymer could simply be produced in two‐step polymerization by using MgCl2.EtOH.TiCl4.DIBP.TEA.cHMDMS catalyst system. Meanwhile, the effect of the step of the hydrogen adding on propylene polymerization was investigated. It was shown that the addition of hydrogen in the second step was more suitable. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1456–1462, 2006
Physical properties of polyamide 6/metallocene isotactic polypropylene conjugated filaments
Authors: Hsiao Kai‐Jen , Jue Zhi‐Feng , Kong Dan‐Cheng , Chen Frank L
Published: May 2006

Polyamide 6 (PA 6) and metallocene isotactic polypropylene (m‐iPP) polymers were extruded (in proportions of 75/25, 50/50, and 25/75) from two melt twin‐screw extruders to prepare three PA 6/m‐iPP conjugated filaments. This study investigated the physical properties of PA 6/m‐iPP conjugated filaments with gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, potentiometry, rheometry, density‐gradient measurements, wide‐angle X‐ray diffraction, extension stress–strain measurements, and scanning electron microscopy. The flow behavior of PA 6/m‐iPP polyblended polymers exhibited negative‐deviation blends, and a 50/50 PA 6/m‐iPP blend showed the minimum value of the melt viscosity. The experimental results from differential scanning calorimetry indicated that PA 6 and m‐iPP molecules formed an immiscible system. The tenacity of the PA 6/m‐iPP conjugated filaments decreased initially and then increased as the m‐iPP content increased. The crystallinities and densities of the PA 6/m‐iPP conjugated filaments had a linear relationship with the blend ratio. Morphological observations revealed that the blends had a dispersed‐phase structure. A pore/fiber morphology of a larger size (from 0.5 to 3 μm in diameter) was observed after a formic acid (PA 6 was moved)/xylene (m‐iPP was moved) treatment on the cross section of a PA 6/m‐iPP conjugated filament. PA 6 and m‐iPP polymers were proved to be an incompatible system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1471–1476, 2006
BSA treatment to enhance enzymatic hydrolysis of cellulose in lignin containing substrates
Authors: Yang Bin , Wyman Charles E.
Published: May 2006

Cellulase and bovine serum albumin (BSA) were added to Avicel cellulose and solids containing 56% cellulose and 28% lignin from dilute sulfuric acid pretreatment of corn stover. Little BSA was adsorbed on Avicel cellulose, while pretreated corn stover solids adsorbed considerable amounts of this protein. On the other hand, cellulase was highly adsorbed on both substrates. Adding a 1% concentration of BSA to dilute acid pretreated corn stover prior to enzyme addition at 15 FPU/g cellulose enhanced filter paper activity in solution by about a factor of 2 and beta‐glucosidase activity in solution by about a factor of 14. Overall, these results suggested that BSA treatment reduced adsorption of cellulase and particularly beta‐glucosidase on lignin. Of particular note, BSA treatment of pretreated corn stover solids prior to enzymatic hydrolysis increased 72 h glucose yields from about 82% to about 92% at a cellulase loading of 15 FPU/g cellulose or achieved about the same yield at a loading of 7.5 FPU/g cellulose. Similar improvements were also observed for enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated corn stover and Douglas fir treated by SO2 steam explosion and for simultaneous saccharification and fermentation (SSF) of BSA pretreated corn stover. In addition, BSA treatment prior to hydrolysis reduced the need for beta‐glucosidase supplementation of SSF. The results are consistent with non‐specific competitive, irreversible adsorption of BSA on lignin and identify promising strategies to reduce enzyme requirements for cellulose hydrolysis. © 2006 Wiley Periodicals, Inc.
Mapping Electrochemiluminescence as Generated at Double‐Band Microelectrodes by Confocal Microscopy under Steady State
Authors: Amatore Christian , Pebay Cécile , Servant Laurent , Sojic Néso , Szunerits Sabine , Thouin Laurent
Published: May 2006

A confocal microspectrometer was used to collect spatially resolved electrochemiluminescence (ECL) spectra from the annihilation reaction between Ru(bpy)3+ and Ru(bpy)33+, each species being generated at a platinum band microelectrode and separated by a micrometric insulating gap. The use of a confocal microspectrometer allows in situ photon detection of the ECL reaction with micrometric spatial resolution and observes the concentration distribution of the photon source in the vicinity of the interelectrode gap.
Phosphorylation and glycosylation interplay: Protein modifications at hydroxy amino acids and prediction of signaling functions of the human β3 integrin family
Authors: Ahmad Ishtiaq , Hoessli Daniel C. , Walker‐Nasir Evelyne , Choudhary M. Iqbal , Rafik Saleem M. , Shakoori Abdul Rauf , Nasir‐ud‐Din
Published: May 2006

Protein functions are determined by their three‐dimensional structures and the folded 3‐D structure is in turn governed by the primary structure and post‐translational modifications the protein undergoes during synthesis and transport. Defining protein functions in vivo in the cellular and extracellular environments is made very difficult in the presence of other molecules. However, the modifications taking place during and after protein folding are determined by the modification potential of amino acids and not by the primary structure or sequence. These post‐translational modifications, like phosphorylation and O‐linked N‐acetylglucosamine (O‐GlcNAc) modifications, are dynamic and result in temporary conformational changes that regulate many functions of the protein. Computer‐assisted studies can help determining protein functions by assessing the modification potentials of a given protein. Integrins are important membrane receptors involved in bi‐directional (outside‐in and inside‐out) signaling events. The β3 integrin family, including, αIIbβ3 and αvβ3, has been studied for its role in platelet aggregation during clot formation and clot retraction based on hydroxyl group modification by phosphate and GlcNAc on Ser, Thr, or Tyr and their interplay on Ser and Thr in the cytoplasmic domain of the β3 subunit. An antagonistic role of phosphate and GlcNAc interplay at Thr758 for controlling both inside‐out and outside‐in signaling events is proposed. Additionally, interplay of GlcNAc and phosphate at Ser752 has been proposed to control activation and inactivation of integrin‐associated Src kinases. This study describes the multifunctional behavior of integrins based on their modification potential at hydroxyl groups of amino acids as a source of interplay. J. Cell. Biochem. 99: 706–718, 2006. © 2006 Wiley‐Liss, Inc.
Transcription factor RFX2 is abundant in rat testis and enriched in nuclei of primary spermatocytes where it appears to be required for transcription of the testis‐specific histone H1t gene
Authors: Wolfe Steven A. , van Wert Jane , Grimes Sidney R.
Published: May 2006

Previous work in our laboratory revealed upregulated transcription of the testis‐specific linker histone H1t gene in pachytene primary spermatocytes during spermatogenesis. Using the H1t X‐box as an affinity chromatography probe, we identified Regulatory Factor X2 (RFX2), a member of the RFX family of transcription factors, as a nuclear protein that binds the probe. We also showed that RFX2 activated the H1t promoter in transient expression assays. However, other RFX family members have the same DNA‐binding domain and they also may regulate H1t gene expression. Therefore, in this study we examined the distribution of RFX2 and other RFX family members in rat testis germinal cells and in several tissues. Among tissues examined, RFX2 is most abundant in testis. Testis RFX2 is most abundant in spermatocytes where transcription of the H1t gene is upregulated and the steady‐state H1t mRNA level is high. RFX2 levels decrease but RFX1 levels increase in early spermatids where H1t gene transcription is downregulated. Antibodies against RFX2 generate a shifted band in electrophoretic mobility shift assays (EMSA) using H1t or testisin X‐box DNA probes with nuclear proteins from spermatocytes. These data support the hypothesis that RFX2 expression is upregulated in spermatocytes where it participates in activating transcription of the H1t gene and other testis genes. These data also support the possibility that other RFX family members may bind to the H1t promoter in other testis germinal cell types and in nongerminal cells to downregulate H1t gene transcription. J. Cell. Biochem. 99: 735–746, 2006. © 2006 Wiley‐Liss, Inc.
Effects of sequential exposure to lipopolysaccharide and heat stress on dental pulp cells
Authors: Kitamura Chiaki , Nishihara Tatsuji , Ueno Yoshiko , Chen Ker‐Kong , Morotomi Takahiko , Yano Junya , Nagayoshi Masato , Terashita Masamichi
Published: May 2006

In the present study, we examined the effects of sequential exposure to bacterial lipopolysaccharide (LPS) and heat stress on dental pulp cells. LPS induced the proliferation of pulp cells through the activation of p38 MAPK. HSP27 was expressed in cells with or without LPS during the entire period of heat stress, while transiently phosphorylated by short‐term heat stress. In LPS‐treated cells, short‐term heat stress also induced the phosphorylation of HSF1. The immediate phosphorylation of HSF1 and HSP27 in LPS‐treated cells by short‐term heat stress occurred dependent on the activation of p38 MAPK. However, with long‐term heat stress, the activation of HSF1 and induction of HSP27 occurred independent of p38 MAPK. Further, full activation of Akt in LPS‐treated cells was immediately induced by short‐term heat stress and lasted during the entire period of heat stress. IκBα was induced and phosphorylated throughout sequential exposure to LPS and heat stress. These results suggest that LPS has the unique effects on the cytoprotection and the cell death of pulp cells during heat stress through the modification and the activation of heat stress responsive molecules, HSF1 and HSP27, and cell survival molecules, Akt and NF‐κB/IκBα. J. Cell. Biochem. 99: 797–806, 2006. © 2006 Wiley‐Liss, Inc.
Proteolytic processing of a sea urchin, ECM‐localized protein into lower mol mass species possessing collagen‐cleavage activity
Authors: Robinson John J.
Published: May 2006

The hyaline layer is an apically located extraembryonic matrix, which blankets the sea urchin embryo. Using gelatin substrate gel zymography, we have identified a number of gelatin‐cleaving activities within the hyaline layer and defined a precursor–product processing pathway which leads to the appearance of 40‐ and 38‐kDa activities coincident with the loss of a 50‐kDa species. Proteolytic processing of the precursor required the presence of both CaCl2 and NaCl at concentrations similar to those found in sea water. The cleavage activities utilized both sea urchin and rat tail tendon gelatins as substrates but demonstrated a species‐specific cleavage activity towards sea urchin collagen. The gelatin‐cleaving activities were refractory to inhibition by 1, 10‐phenanthroline but were inhibited by benzamidine. This latter result defines the serine protease nature of the cleavage activities. Both the 40‐ and 38‐kDa activities were found to comigrate with gelatin‐cleaving activities present in the sea urchin embryo. J. Cell. Biochem. 99: 816–823, 2006. © 2006 Wiley‐Liss, Inc.