bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimativas de repetibilidade para caracteres forrageiros em Panicum maximum
Authors: Lédo Francisco José da Silva , Pereira Antônio Vander , Souza Sobrinho Fausto de , Auad Alexander Machado , Jank Liana , Oliveira Jackson Silva e
Published: August 2008

Objetiva-se com este trabalho estimar a repetibilidade para caracteres forrageiros de Panicum, e determinar o número de cortes de avaliação necessários para a seleção de genótipos de Panicum, com confiabilidade. Utilizaram-se os dados de um ensaio conduzido no período de 21/11/2002 a 08/04/2005, no Campo Experimental da Embrapa Gado de Leite, localizado em Valença-RJ, onde foram realizados 15 cortes de avaliação. No ensaio, foram avaliados 23 genótipos de Panicum maximum, em parcelas experimentais, dispostas no delineamento de blocos casualizados, com três repetições. Foram estimados os coeficientes de repetibilidade para as características produção de matéria verde de forragem (PMV); produção de matéria seca de forragem (PMS) e de folhas (PMSF); porcentagem de folhas na PMS (%FOL) e altura da planta (AP), utilizando os métodos da análise de variância, componentes principais e análise estrutural. Para todas as características avaliadas os efeitos de genótipos, cortes e interação genótipos x cortes foram significativos (P<0,01). Quando se considerou o coeficiente de determinação de 85%, o número de avaliações (cortes) necessários para a determinação do valor real dos genótipos foram de 10, 9, 7, 11 e 3, respectivamente, para PMV, PMS, PMSF, %FOL e AP. O método dos componentes principais e o da análiseestrutural (baseado na matriz de correlações) foram concordantes para todas as características avaliadas. A realização de 10 cortes de avaliação permite discriminar o valor real dos genótipos de Panicum, com confiabilidade superior a 85%, para a maioria das características avaliadas.
Regeneração de Euphorbia heterophylla L. in vitro
Authors: Colussi Francieli , Dabul Audrei Nisio Gebieluca , Ayub Ricardo Antonio
Published: August 2008

Objetivou-se neste trabalho estudar a regeneração in vitro da planta daninha Euphorbia heterophylla a partir de explantes hipocotiledonares, cotiledonares e radiculares com diferentes concentrações do hormônio 2iP, combinado ou não com auxina e cinetina adicionado ao meio MS/2. Foram avaliados os números de explantes com gema, número de gemas por explante, número de plântulas enraizadas e aclimatadas. Obteve-se em média duas gemas por explante hipocotiledonar em 50% desses, a partir de organogênese direta com o uso de 0,5 mg.L-1 de 2iP. Não houve regeneração a partir dos explantes cotiledonares e radiculares. A cultura racinar desenvolveu-se em todos os tratamentos contendo ou não auxina. Esses resultados poderão auxiliar em futuros testes fisiológicos de resistência dessa planta a herbicidas.
Produção de matéria seca de cultivares de milho sob diferentes níveis de estresse hídrico
Authors: Costa Jacirema R. da , Pinho João L. N. de , Parry Maurício M.
Published: August 2008

Objetivando-se identificar algumas características da cultura do milho que lhe confiram melhor estabilidade de produção quando explorado nas condições climáticas do semi-árido nordestino, avaliou-se o desempenho fenotípico de duas cultivares de milho, m(-2)1 e BR-106, face aos diferentes níveis de água disponível (AD) no solo, nos estádios vegetativo e reprodutivo, em relação à produção de matéria seca. O experimento foi conduzido em casa de vegetação, no delineamento blocos ao acaso, com quatro tratamentos (níveis de água disponível): a) testemunha (100% AD); b) plantas com 75% AD; c) 50% AD e, d) plantas submetidas ao ponto de murcha permanente. O estresse aplicado no estádio vegetativo reduziu o conteúdo relativo de água, área foliar, matéria seca das raízes (MSR) e parte aérea das plantas. No estádio reprodutivo, os tratamentos também influenciaram negativamente esses parâmetros, exceto a produção de MSR, que não apresentou resposta e a cultivar BR-106 mostrou-se mais tolerante ao déficit hídrico nos dois estádios fenológicos estudados.
Eficiência produtiva de cultivares de arroz com divergência fenotípica
Authors: Guimarães Cleber M. , Stone Luís F. , Neves Péricles de C. F.
Published: August 2008

O objetivo do trabalho foi avaliar, fenotipicamente, as cultivares de arroz tradicionais Guarani e Caiapó, e as modernas, CIRAD L(-1)41, Maravilha, BR IRGA 409 e Metica 1, por meio da associação entre os vários componentes da produtividade de grãos, para prover base de seleção genética em populações de plantas. O estudo foi conduzido na estação chuvosa do ano agrícola de 2003-2004, na área experimental da Embrapa Arroz e Feijão, em Santo Antônio de Goiás, GO. Em condições de sequeiro, com suplementação hídrica, as cultivares de arroz de terras altas CIRAD L(-1)41, Guarani, Caiapó e Maravilha, apresentaram maiores índices de colheita e menores percentagens de esterilidade de espiguetas que as de arroz irrigado BR IRGA 409 e Metica 1. Concluiu-se que a maior produção de biomassa pelas cultivares de arroz irrigado não se refletiu na produtividade de grãos. A CIRAD L(-1)41 por apresentar alta área foliar, panículas densas com alto número de grãos e um comportamento intermediário em todos os componentes avaliados, como índice de colheita, massa dos grãos, fertilidade de perfilhos, perfilhamento, esterilidade de espiguetas e taxa de crescimento, produziu 12,5% a mais que a segunda mais produtiva. O aumento do índice de colheita e da massa dos grãos e a redução da esterilidade das espiguetas devido às suas altas correlações com a produtividade, são considerados prioritários em programas de melhoramento de arroz que visem obter cultivares mais produtivas.
Fluxo de vapor de água atmosférico na obtenção do resíduo ET-P em três macrorregiões brasileiras
Authors: Cavalcanti Enilson P. , Gomes Filho Manoel F. , Bezerra Wagner de A.
Published: August 2008

São analisados, neste trabalho, a precipitação, a evapotranspiração e o resíduo (ET-P) para três áreas de controle de 10 por 10 graus de latitude e longitude sobre as regiões Nordeste, Norte e Sudeste do Brasil. O fluxo de vapor d'água resultante é calculado e comparado com o resíduo. As análises são feitas a partir dos dados de reanálise mensais do National Center for Atmospheric Research/National Centers for Environmental Prediction - NCAR/NCEP, para o período de 1958 a 1998. Aspectos da variação sazonal e interanual dos elementos citados são apresentados para cada uma das áreas e, entre os resultados obtidos, destacam-se a boa correlação entre o resíduo e o fluxo de vapor d'água resultante, com coeficientes de determinação de 0,86, 0,84 e 0,74 para as áreas Nordeste, Norte e Sudeste, respectivamente.
Variação vertical da temperatura do ar no dossel de plantas de batata
Authors: Tazzo Ivonete F. , Heldwein Arno B. , Streck Luciano , Trentin Gustavo , Grimm Edenir L. , Maass Guilherme F. , Maldaner Ivan C.
Published: August 2008

A temperatura do ar é um dos elementos meteorológicos mais importantes no condicionamento da infecção causada por patógenos, ante o que se propôs, com este trabalho, determinar a variação vertical da temperatura do ar no dossel de plantas de batata, cultivar Macaca; para tal, dois experimentos foram realizados, um na primavera, de 15/10 a 05/12/2003, em uma propriedade rural no município de Silveira Martins, RS, e o segundo no outono, de 27/03 a 08/06/2004, no Departamento de Fitotecnia da Universidade Federal de Santa Maria, RS. Foram instaladas uma torre com cinco níveis de medições psicrométricas contínuas e três repetições de psicrômetros, a meia altura das plantas e a 1,0 m de altura. Cada par psicrométrico constou de dois termômetros de resistência elétrica de platina (PT - 100), acomodados no interior de um mini-abrigo. Todos os sensores foram ligados a uma datalogger. As diferenças médias de temperatura entre 2,2 e 0,15 m de altura (T2,2 - T0,15) em 2003, foram de -1,72 oC no período diurno (das 11 às 17 h) e de +0,82 oC no período noturno (das 21 às 4 h). Em 2004 as diferenças médias de temperatura entre os níveis extremos de 2,0 e 0,10 m (T2,0 - T0,10) foram de -1,12 oC no período diurno e de -0,62 oC no período noturno. A temperatura média diuna é maior nos níveis inferiores do dossel, sendo os gradientes de temperatura do ar mais acentuados durante o período diurno do que durante a noite.
Variabilidade espacial de variáveis geobiofísicas nas nascentes da bacia hidrográfica do Ribeirão Santa Cruz
Authors: Alves Marcelo de C. , Botelho Soraya A. , Pinto Lilian V. A. , Pozza Edson A. , Oliveira Marcelo S. de , Ferreira Elizabeth , Andrade Hélcio
Published: August 2008

Objetivou-se, em Lavras, MG, caracterizar a estrutura e a magnitude de dependência espacial de variáveis ambientais nas nascentes da bacia hidrográfica do Ribeirão Santa Cruz, por métodos de interpolação geoestatística. Os métodos de interpolação por krigagem ordinária e inverso da potência da distância (IPD) foram utilizados para representar altitude, vazão, áreas de recarga e de vegetação de 175 nascentes perenes em 86,99 km² de área. Observou-se melhor desempenho da estimação por krigagem quando comparado ao método IPD.
Desempenho dinâmico de um trator agrícola utilizando biodiesel destilado de óleo residual
Authors: Soranso Ana M. , Gabriel Filho Antonio , Lopes Afonso , Souza Eduardo G. de , Dabdoub Miguel J. , Furlani Carlos E. A. , Camara Felipe T. da
Published: August 2008

Propôs-se, com este trabalho, avaliar o desempenho dinâmico de um trator agrícola funcionando com biodiesel destilado (50% etílico + 50% metílico) em função das proporções de biodiesel e diesel de petróleo (0 e 100%, 5 e 95%, 15 e 85%, 25 e 75%, 50 e 50%, 75 e 25% e 100 e 0%) respectivamente. O experimento foi realizado na área do Departamento de Engenharia Rural da Universidade Estadual Paulista - UNESP, Campus de Jaboticabal, SP, localizado na latitude 21º 14' 28" S e longitude 48º 17'12" W. Utilizou-se um trator 4 x 2 TDA com potência de 73,6 kW (100 cv) no motor e um trator de lastro. O biodiesel utilizado foi produzido à base de óleo residual de fritura de alimentos, o delineamento experimental foi inteiramente casualizado (DIC), com 7 tratamentos e 5 repetições, totalizando 35 observações, e os resultados evidenciaram que a mistura biodiesel e diesel de petróleo influenciou significativamente as variáveis consumo horário volumétrico, consumo horário mássico, consumo de combustível por área trabalhada e consumo específico. Quando o trator operou com 100% de biodiesel (B100) o consumo específico aumentou em média 18% em relação ao diesel (B0).
Oxidative stress and DNA damage in broad bean (Vicia faba L.) seedlings induced by thallium
Authors: Radić Sandra , Cvjetko Petra , Glavas Katarina , Roje Vibor , Pevalek-Kozlina Branka , Pavlica Mirjana
Published: August 2008

Thallium (Tl) is a metal of great toxicological concern because it is highly toxic to all living organisms through mechanisms that are yet poorly understood. Since Tl is accumulated by important crops, the present study aimed to analyze the biological effects induced by bioaccumulation of Tl in broad bean (Vicia faba L.) as well as the plant's antioxidative defense mechanisms usually activated by heavy metals. Thallium toxicity was related to production of reactive oxygen species in leaves and roots of broad bean seedlings following short-term (72 h) exposure to thallium (I) acetate (0, 0.5, 1, 5, and 10 mg/L) by evaluating DNA damage and oxidative stress parameters as well as antioxidative response. The possible antagonistic effect of potassium (K) was tested by combined treatment with 5 mg/L of Tl (Tl+) and 10 mg/L of potassium (K+) acetate. Accumulation of Tl+ in roots was 50 to 250 times higher than in broad bean shoots and was accompanied by increase in dry weight and proline. Despite responsive antioxidative defense (increased activities of superoxide dismutase, ascorbate peroxidase, and pyrogallol peroxidase), Tl+ caused oxidative damage to lipids and proteins as evaluated by malondialdehyde and carbonyl group levels, and induced DNA strand breaks. Combined treatment caused no oxidative alternations to lipids and proteins though it induced DNA damage. The difference in Tl-induced genotoxicity following both acellular and cellular exposure implies indirect DNA damage. Results obtained indicate that oxidative stress is involved in the mechanism of Tl toxicity and that the tolerance of broad bean to Tl is achieved, at least in part, through the increased activity of antioxidant enzymes.
Nonadditive effects in the partitioning behavior of various aliphatic and aromatic molecules
Authors: Goss Kai-Uwe , Arp Hans Peter H. , Bronner Guido , Niederer Christian
Published: August 2008

Predicting the partition behavior of bifunctional molecules from their molecular structure is a challenge because the combination of two or more functional groups often has nonadditive effects. Data presented here and in the literature reveal that isomers of bifunctional compounds can exhibit partition constants that differ by several orders of magnitude. These effects are not limited to compounds with intramolecular H-bonds. For aliphatic molecules, large effects are found for diones and diesters but not for dioles. For aromatic molecules, large effects are found for compounds with intramolecular H-bonds and also for p-isomers with a strong delocalisation of π-electrons over both functional groups as in p-nitroaniline and p-nitrophenol. Interestingly, these nonadditive effects apply not only to the specific interactions but also to the van der Waals interactions of a molecule. This diversity of possible nonadditive effects makes it difficult to predict partitioning of such polyfunctional molecules. Our results suggest that successful models require either an extensive number of correction factors or a quantum chemical approach. Predicting partitioning of bifunctional molecules to environmental systems might face an additional complication. Unlike with solvents, steric limitations of natural phases may prevent them from forming multiple H-bonds with bifunctional molecules. Our experimental results, however, indicate that this situation does not occur, as the H-bond-interaction behavior of bifunctional molecules in humic matter and on quartz was the same as it was in various solvent systems.
Sprint Training Increases Muscle Oxidative Metabolism During High-Intensity Exercise in Patients With Type 1 Diabetes
Authors: Harmer Alison R. , Chisholm Donald J. , McKenna Michael J. , Hunter Sandra K. , Ruell Patricia A. , Naylor Justine M. , Maxwell Lyndal J. , Flack Jeff R.
Published: August 2008

OBJECTIVE—To investigate sprint-training effects on muscle metabolism during exercise in subjects with (type 1 diabetic group) and without (control group) type 1 diabetes.

RESEARCH DESIGN AND METHODS—Eight subjects with type 1 diabetes and seven control subjects, matched for age, BMI, and maximum oxygen uptake (V̇o2peak), undertook 7 weeks of sprint training. Pretraining, subjects cycled to exhaustion at 130% V̇o2peak. Posttraining subjects performed an identical test. Vastus lateralis biopsies at rest and immediately after exercise were assayed for metabolites, high-energy phosphates, and enzymes. Arterialized venous blood drawn at rest and after exercise was analyzed for lactate and [H+]. Respiratory measures were obtained on separate days during identical tests and during submaximal tests before and after training.

RESULTS—Pretraining, maximal resting activities of hexokinase, citrate synthase, and pyruvate dehydrogenase did not differ between groups. Muscle lactate accumulation with exercise was higher in type 1 diabetic than nondiabetic subjects and corresponded to indexes of glycemia (A1C, fasting plasma glucose); however, glycogenolytic and glycolytic rates were similar. Posttraining, at rest, hexokinase activity increased in type 1 diabetic subjects; in both groups, citrate synthase activity increased and pyruvate dehydrogenase activity decreased; during submaximal exercise, fat oxidation was higher; and during intense exercise, peak ventilation and carbon dioxide output, plasma lactate and [H+], muscle lactate, glycogenolytic and glycolytic rates, and ATP degradation were lower in both groups.

CONCLUSIONS—High-intensity exercise training was well tolerated, reduced metabolic destabilization (of lactate, H+, glycogenolysis/glycolysis, and ATP) during intense exercise, and enhanced muscle oxidative metabolism in young adults with type 1 diabetes. The latter may have clinically important health benefits.
Normal Glucose Values Are Associated With a Lower Risk of Mortality in Hospitalized Patients
Authors: Bruno Alberto , Gregori Dario , Caropreso Antonio , Lazzarato Fulvio , Petrinco Michele , Pagano Eva
Published: August 2008

OBJECTIVE—Hyperglycemia is a common condition in hospitalized patients. The aim of this study was to investigate the relationships between glycemia upon admission and mortality in a heterogeneous group of adult patients.

RESEARCH DESIGN AND METHODS—The 3-year records released from a general hospital were associated with a plasma glucose dataset of its general laboratory. A matched case-control study was implemented (3,338 case-control subject pairs). All-patient refined diagnosis–related groups and the relative risk of death were the matching criteria. A multivariate conditional logistic regression model was used to evaluate the associations between death and glycemia.

RESULTS—Higher in-hospital mortality was associated with hyperglycemia or hypoglycemia, whereas lower risk was observed for values between 78 and 101 mg/dl.

CONCLUSIONS—Our data confirm the relation between glycemia upon admission and mortality and suggest that slightly increased or decreased plasma glucose can be linked with increased mortality risk.
Euglycemic Hyperinsulinemia Alters the Response to Orthostatic Stress in Older Adults With Type 2 Diabetes
Authors: Madden Kenneth M. , Tedder Gale , Lockhart Chris , Meneilly Graydon S.
Published: August 2008

OBJECTIVE—Insulin has opposing influences on blood pressure by simultaneously increasing adrenergic activity and vasodilatating peripheral blood vessels. In this study, we sought to determine whether hyperinsulinemia affects tilt table responses in older adults with type 2 diabetes not complicated by orthostatic hypotension.

RESEARCH DESIGN AND METHODS—Twenty-two older adults (mean age 71.7 ± 1.1) with diet-controlled or oral hypoglycemic drug–controlled type 2 diabetes were recruited. All subjects with orthostatic hypotension, diabetic nephropathy, and sensory neuropathy were excluded. Subjects underwent euglycemic-hyperinsulinemic clamp and placebo “sham clamp” sessions. Sequential euglycemic-hyperinsulinemic clamps were performed for 2 h at 40 mU · m−2 · min−1 (low dose) and 2 h at 80 mU · m−2 · min−1 (high dose), and each was followed by a head-up tilt table test at 70°C for 10 min.

RESULTS—There were no incidents of presyncope during the sham clamp, whereas there were four presyncopal events during both the low-dose and high-dose tilts. Although the low-dose clamp showed no difference in the response between sessions (two-way ANOVA), subjects demonstrated a significantly larger decrease in mean arterial pressure (P = 0.005) and diastolic blood pressure (P = 0.08) during the high-dose tilt. Doppler measures of middle cerebral artery velocity were no different between the two sessions at either dose.

CONCLUSIONS—The vasodilatory response to insulin can unmask orthostatic intolerance in older adults with type 2 diabetes, resulting in presyncopal symptoms. This could contribute to orthostatic hypotension in combination with other factors such as hyperthermia, hypovolemia, and adverse effects from medications.
Interaction of Air and High-Speed Rail in Japan
Authors: Clever Reinhard , Hansen Mark M.
Published: August 2008

There has been a unique convergence of factors that have contributed to Japan's outstanding public transportation system. The paper focuses on two modes of transportation: air and high-speed rail (HSR). These two modes do not complement each other as in Europe, but compete head-on in Japan. Moreover, Japan does not have to contend with market-distorting public subsidies, because both companies operating HSR in the corridor of interest are highly profitable, primarily because of their HSR service. The Japanese transportation system therefore provides an excellent environment in which to study the nature of competition between air and HSR. (Conventional rail is also discussed where appropriate.) Individual contributors to terminal pair choice are contrasted between air and HSR, and the trade-offs between accessibility, frequency, and speed are analyzed in detail.
Train Slot Cooperation in Multicarrier, International Rail-Based Intermodal Freight Transport
Authors: Kuo April , Miller-Hooks Elise , Zhang Kuilin , Mahmassani Hani
Published: August 2008

Collaborative decision-making (CDM) strategies are proposed for the collaborative operation of international rail-based intermodal freight services by multiple carriers. The benefits of the proposed techniques are assessed using a carrier collaboration simulation—assignment framework on a real-world European intermodal network spanning 11 countries from Scandinavia to Greece through Bulgaria, Czech Republic, Hungary, Poland, Romania, and Slovakia. This is termed the REORIENT corridor. Three CDM strategies are presented in this work: (a) train slot cooperation, (b) train space leasing, and (c) train slot swapping. Results of numerical experiments indicate that these strategies are expected to result in significant improvements in terms of shipments that are attracted to the proposed services. The best-performing CDM strategy, train slot swapping, resulted in a more than 40% increase in terms of ton-kilometers attracted to proposed services. Such CDM strategies result in a win–win situation for all parties. In addition to attracting more demand, cost savings in terms of rolling stock and labor and reduced shipment delays can be achieved. The potential of such strategies for a real-world application is discussed.
New Decision Support System for Optimization of Rail Track Maintenance Planning Based on Adaptive Neurofuzzy Inference System
Authors: Dell'Orco Mauro , Ottomanelli Michele , Caggiani Leonardo , Sassanelli Domenico
Published: August 2008

It is well known that maintenance planning affects, in general, the life of the structures, material wear, and quality of service. In particular, the maintenance of rail tracks affects the traffic volume as well, and therefore it is an important issue for the management of a railway system. Accurate maintenance planning is necessary to optimize resources. The condition of railways is checked by special diagnostic trains. Because of the vast amount of data that these trains record, it is necessary to analyze these data through an appropriate decision support system (DSS). However, the most up-to-date DSSs, such as EcoTrack, are based on a binary logic with rigid thresholds and complicated algorithms with a large number of rules that restrict their flexibility in use. In addition, they adopt considerable simplifications in the rail track deterioration model. In this paper, a neurofuzzy inference engine has been implemented for a DSS to overcome these drawbacks. Based on fuzzy logic, it was able to handle thresholds expressed as a range, an approximate number, or even a verbal value. Moreover, through artificial neural networks, it was possible to obtain more precise rail track deterioration models. The results obtained with the proposed model have been clustered through a fuzzy procedure to optimize the maintenance schedule, thus grouping the interventions in space and in time.
Testing of Slab Track under Heavy Axle Loads
Authors: Li Dingqing , Bilow David N.
Published: August 2008

In July 2003, two types of slab tracks were installed on the high tonnage loop at the Facility for Accelerated Service Testing, Pueblo, Colorado. Direct fixation slab track (DFST) and independent dual block track (IDBT) were installed into a 5° curve. The total slab track test section is 500 ft long, consisting of 250 ft of IDBT and 250 ft of DFST. The transition from each slab to the adjacent ballasted track is in a spiral to tangent track. For 3 years, more than 170 million gross tons of heavy axle load (HAL) traffic was accumulated and the slab track test section was capable of supporting HAL train operations, while maintaining track geometry conditions for a Class 9 track. This paper summarizes part of the test results and the main conclusions of the slab track test, which is described more completely in a report published by the Portland Cement Association.
Effects of Route Rationalization on Hazardous Materials Transportation Risk
Authors: Kawprasert Athaphon , Barkan Christopher P. L.
Published: August 2008

Hazardous materials traffic originates and terminates at numerous locations throughout the North American railroad network. Rerouting of this traffic, especially toxic inhalation hazard materials, away from populated areas has received considerable attention in recent years as a means of reducing risk. However, rerouting on a route-specific basis is neither simple nor necessarily effective at reducing risk because of physical constraints in the configuration of the rail network and the possible need to increase the miles traveled by hazardous materials so as to avoid populated areas. A more comprehensive approach is rationalization of the transportation route structure for these materials. This does not simply involve trying to reroute traffic between the current set of origins and destinations to avoid population centers en route. Instead, route rationalization encompasses analysis of the entire route structure for a particular material. The objective is to identify opportunities to reduce risk by considering critical factors associated with each possible route, while simultaneously taking into account the production and consumption levels at each location in the network. This paper presents a risk analysis model combined with an optimization technique to formally consider risk reduction by means of rationalization of the hazardous materials transportation rail route structure. The model is flexible and enables optimization of the route structure based on a variety of possible objective functions, including minimization of miles traveled, accident (derailment) probability, likelihood of release, population exposure, and risk.
High‐Performance Organic Transistor Memory Elements with Steep Flanks of Hysteresis
Authors: Wu Weiping , Zhang Hongliang , Wang Ying , Ye Shanghui , Guo Yunlong , Di Chongan , Yu Gui , Zhu Daoben , Liu Yunqi
Published: August 2008

High‐performance organic transistor memory elements with donor‐polymer blends as buffer layers are presented. These organic memory transistors have steep flanks of hysteresis with an ON/OFF memory ratio of up to 2 × 104, and a retention time in excess of 24 h. Inexpensive materials such as poly(methyl methacrylate), ferrocene and copper phthalocyanine are used for the device fabrication, providing a convenient approach of producing organic memory transistors at low cost and high efficiency.
Epidemiology, risk and prognostic factors in mesenteric venous thrombosis
Authors: Acosta S , Alhadad A , Svensson P , Ekberg O
Published: August 2008

Background

Epidemiological reports on risk and prognostic factors in patients with mesenteric venous thrombosis (MVT) are scarce.

Methods

Patients with MVT were identified through the inpatient and autopsy registry between 2000 and 2006 at Malmö University Hospital.

Results

Fifty-one patients had MVT, diagnosed at autopsy in six. The highest incidence (11·3 per 100 000 person-years) was in the age category 70–79 years. Activated protein C resistance was present in 13 of 29 patients tested. D-dimer at admission was raised in all five patients tested. Multidetector row computed tomography (CT) in the portal venous phase was diagnostic in all 20 patients investigated, of whom 19 were managed conservatively. The median length of resected bowel in 12 patients who had surgery was 0·6 (range 0·1–2·2) m. The overall 30-day mortality rate was 20 per cent; intestinal infarction (P = 0·046), treatment on a non-surgical ward (P = 0·001) and CT not done (P = 0·022) were associated with increased mortality. Cancer was independently associated with long-term mortality: hazard ratio 4·03, 95 per cent confidence interval 1·03 to 15·85; P = 0·046.

Conclusion

Portal venous phase CT appeared sensitive in diagnosing MVT. As activated protein C resistance was a strong risk factor, lifelong anticoagulation should be considered.
Getting involved: Testing the effectiveness of a volunteering intervention on young adolescents' future intentions
Authors: Wilson Anne E. , Allen James W. , Strahan Erin J. , Ethier Nicole
Published: August 2008

Past research has identified a host of benefits associated with volunteering and community involvement, yet involvement appears to be on the decline in recent years. We tested the effectiveness of an intervention designed to encourage involvement. We provided young adolescents with information about volunteer opportunities, benefits and ways to overcome barriers to involvement. Adolescents who participated in the volunteering intervention reported greater involvement intentions than control participants. In addition, mediation analyses indicated that adolescents in the volunteering intervention based their self‐worth to a greater degree on virtuous behaviour, which in turn predicted their involvement intentions, especially in the helping domain. Copyright © 2008 John Wiley & Sons, Ltd.
Investigation on a Potential Targeting Drug Delivery System Consisting of Folate, Mitoxantrone and Human Serum Albumin
Authors: ZHOU Qiu‐Ju , BI Ya‐Jing , XIANG Jun‐Feng , TANG Ya‐Lin , YANG Qian‐Fan , XU Guang‐Zhi
Published: August 2008

A potential targeting drug delivery system consisting of folate (FA), the targeting molecule, human serum albumin (HSA), the carrier, and mitoxantrone (MTO), the medicine, has been designed. Data obtained by UV absorption, fluorescence, and NMR techniques indicated the formation of ternary complexes and possible application to building a targeting drug delivery system by using FA, MTO and HSA. Furthermore, cytotoxicity assay indicated that the toxicity of the FA‐HSA‐MTO against PC‐3 cell line was 79.95%, which was much higher than that of free MTO tested in totally the same conditions. About 30% increase of the toxicity should be owed to the targeting effect of FA. Thus, the feasibility and validity of a novel targeting drug delivery system, FA‐HSA‐MTO, was confirmed.
Effect of Cadion 1B on the Spectrum of Mercaptoacetic Acid‐stabilized CdTe Quantum Dots
Authors: WEN Li‐Qun , ZHOU Xing‐Wang , LÜ Jian‐Quan
Published: August 2008

The effect of cadion 1B (4‐nitro‐benzene‐diazo‐amino‐azobenzene) on the fluorescent and absorption spectroscopy of mercaptoacetic acid‐stabilized CdTe quantum dots (CdTe QD) in aqueous media was studied. Surfactant, medium, dosages of the cadion 1B, pH and thermodynamics parameters were also examined. The experimental results showed that when cadion 1B was added into the CdTe QD solution, a new absorption peak was observed, and the fluorescence of CdTe QD was quenched to some extent, suggesting that there exist an interaction between cadion 1B and CdTe QD. The apparent equilibrium constant at room temperature was calculated to be 1.095×106 L·mol−1, and the coverage ratio of cadion 1B on the surface of CdTe QD was estimated as 45%. Thermodynamic calculations revealed that the interaction was a spontaneous process in which electrostatic interactions play a major role.
Immunonanogold Catalytic Resonance Scattering Spectral Assay of Trace Immunoglobulin M
Authors: LIANG Ai‐Hui , WANG Su‐Mei , JIANG Zhi‐Liang
Published: August 2008

Gold nanoparticles of 10 nm were prepared by the improved method of trisodium citrate, and used to label goat anti‐human immunoglobulin M (anti‐IgM) to obtain a resonance scattering spectral probe for IgM. In pH 4.5 KH2PO4‐Na2HPO4 buffer solution and in the presence of polyethylene glycol, the nanogold‐labeled anti‐IgM was combined with IgM specifically to form immunogold complex particles. After centrifugation, the immunonanogold in the supernatant catalyzed the reduction of AuCl4− ions by NH2OH·HCl to form larger size gold particles in pH 1.9 citrate buffer solution, making the resonance scattering intensity at 580 nm enhanced. The amount of the nanogold‐labeled anti‐IgM in the supernatant decreased with the addition of IgM. The decreased intensity ΔI580 nm was proportional to the concentration of IgM in the range of 0.06–4.80 ng·mL−1. The regression equation was ΔI580 nm=14.5c(IgM)+1.8, with a detection limit of 0.03 ng·mL−1 IgM. The method was applied to the determination of IgM in sera of healthy humans, with satisfactory results.
Synthesis ofo‐[N‐(Substituted benzoyl)‐N‐methylamino]phenyl Disulfides by the Spontaneous Coupling ofN‐Methyl‐2‐mono(substituted phenyl)benzothiazolines in Solution and Their VEGF Inhibitory Activities
Authors: TANG Jian , ZHANG Bei‐Na , GE Mei , ZHU Li , WANG Yang , CHEN Ying , XIA Peng
Published: August 2008

The solidN‐methyl‐2‐mono(substituted phenyl)benzothiazolines (1) are stable and can be stored in atmosphere, whereas they present different behavior in different solvents. They are relatively stable in alcohol and DMSO‐H2O. However, in other organic solvents such as acetone, CH2Cl2, CHCl3, EtOAcetc., the oxidation‐coupling reactions occurred spontaneously to give the corresponding disulfide dimers2. The substituents at 2‐phenyl rings, reaction temperature and the acidities of the solutions exerted obvious impacts on the reaction rates and yields of2. 12 samples ofN‐methyl‐2‐(substituted phenyl)benzothiazolines (1) and 11 dimers2were evaluatedinvitrovascular endothelial growth factor (VEGF) inhibitory activity in human breast cancer cell MDA‐MB‐231 with 2‐methoxyestradiol (2‐ME) as the positive reference and most of them showed potent VEGF inhibitory activity with the EC50values of sub‐millimolar range. Among them, the compounds1l,1i, and2dshowed potent VEGF inhibitory activities and selectivities with EC50values of 0.07, <0.12, and 0.03 mmol/L and SI values of 25, >32 and >32, respectively, which were about 10 times of those of 2‐ME (EC50=0.49 mmol/L, SI=3.37). The results further demonstrated that the scaffolds of1and2were privileged and merited further investigation as VEGF inhibitors.
Synthesis, Crystal Structure and Bioactivities of N‐(4‐Methyl‐ benzamido)‐ N′‐[5‐(2‐trifluoromethylphenyl)‐2‐furoyl]thiourea
Authors: XUE Si‐Jia , BIAN Wang‐Dong , CHAN An , YU Song‐Rui
Published: August 2008

The title compound N‐(4‐methylbenzamido)‐N′‐[5‐(2‐trifluoromethylphenyl)‐2‐furoyl]thiourea has been synthesized for the first time and its crystal structure (C21H16F3N3O3S, Mr=447.43) has been determined by single‐crystal X‐ray diffraction analysis. The crystal belongs to monoclinic, space group P‐1 with a=0.9677(7) nm, b=1.0461(8) nm, c=1.0771(7) nm, β=98.912(6)°, V=1.0083(12) nm3, Z=2, Dc=1.474 g/cm3, µ=0.22 mm−1, F(000) =460, R=0.0445 and wR=0.194 for 3504 unique reflections with 2598 observed ones [I>2δ(I)]. In the crystal structure, there are some intra‐ and intermolecular hydrogen bonds and C–H··· interaction between the molecules, which stabilize the crystal structure. The preliminary bioassay shows that the title compound exhibits good fungicidal activities against Fusarium oxysporium, Botrytis cinereapers, and Dothiorella gregaria.
A phase 2 trial of sequential temozolomide chemotherapy followed by high‐dose interleukin 2 immunotherapy for metastatic melanoma
Authors: Tarhini Ahmad A. , Kirkwood John M. , Gooding William E. , Moschos Stergios , Agarwala Sanjiv S.
Published: August 2008

BACKGROUND.

Previous biochemotherapy regimens for metastatic melanoma have required attenuated dosages of interleukin 2 (IL‐2) that may have compromised efficacy.

METHODS.

In a phase 2 study, the authors tested sequential temozolomide (75 mg/m2 per day orally for 3 weeks) followed by high‐dose, IL‐2 (600,000 U/kg per dose intravenously; maximum, 14 doses over 5 days).

RESULTS.

Thirty‐eight patients with treatment‐naive American Joint Committee on Cancer stage IV melanoma (8 patients with M1a disease, 6 patients with M1b disease, and 24 patients with M1c disease) were enrolled. Ten patients had a history of treated brain metastases. Thirty‐one patients who received at least 2 cycles of IL‐2 were evaluable for response. Grade 3 toxicities included hyperbilirubinemia (9 patients), hematologic toxicities (leukopenia in 5 patients, thrombocytopenia in 3 patients), diarrhea (2 patients), and oliguria (1 patient). One patient had grade 4 nausea. The overall response rate (ORR) was 16% and included 3 complete responses that lasted 10.8 months, ≥32 months, and ≥36 months and 2 partial responses that lasted 13 months and 14 months. Responses were observed in patients with M1a disease and in patients with M1c disease. Sixteen patients had stable disease (15 patients progressed). The median progression‐free survival (PFS) was 5.3 months (95% confidence interval [CI], 3.7‐7.5 months). The probability of PFS at 6 months was 0.52 (95% CI, 0.33‐0.67). Among 38 enrolled patients, 16 patients remained alive at a median follow‐up of 6.7 months (range, 1.9‐36.1 months). The median overall survival (OS) was 12.1 months (95% CI, 9.1‐16.4 months), and the probability of 12‐month OS was 0.54 (95% CI, 0.34‐0.70 months).

CONCLUSIONS.

The current results indicated that it is safe to administer HD IL‐2 sequentially with temozolomide and that this combination has lower toxicity than previously used concurrent biochemotherapy regimens. However, The ORR and the durability of responses with this combination did not exceed those of single‐agent HD IL‐2. Cancer 2008. © 2008 American Cancer Society.
Risk of subsequent endometrial carcinoma associated with endometrial intraepithelial neoplasia classification of endometrial biopsies
Authors: Lacey James V. , Mutter George L. , Nucci Marisa R. , Ronnett Brigitte M. , Ioffe Olga B. , Rush Brenda B. , Glass Andrew G. , Richesson Douglas A. , Chatterjee Nilanjan , Langholz Bryan , Sherman Mark E.
Published: August 2008

BACKGROUND.

Histopathologic diagnosis of endometrial biopsies is used to estimate the risk of progression to carcinoma and guide clinical management. Problems with the widely used World Health Organization (WHO) system for classifying endometrial hyperplasia (EH) have prompted the development of an alternative system based on endometrial intraepithelial neoplasia (EIN). The authors estimated progression risk associated with EIN among endometrial biopsies in a nested case‐control study of EH progression.

METHODS.

Index biopsies with original community pathology diagnoses of disordered proliferative endometrium (DPEM) or EH that were independently confirmed by a panel of pathologists were independently reviewed and assigned EIN classifications (inadequate, benign, EIN, or cancer) by a second panel of pathologists. Cases (N = 138) progressed to carcinoma at least 1 year (median, 6 years) after their index biopsy. Controls (N = 241) also had EH, did not progress to carcinoma, and were individually matched to cases based on age at EH, date of EH, and length of follow‐up. By using conditional logistic regression, the authors estimated relative risks (RRs) with 95% confidence intervals (95% CIs) for progression to carcinoma for EIN versus benign.

RESULTS.

In the EIN system, 71 (52.6%) cases and 159 (66.8%) controls were classified as benign and 42 (31.1%) cases and 65 (27.3%) controls were classified as EIN. The RR for EIN versus benign was 7.76 (95% CI, 3.36‐17.91). In the WHO system, the RR for atypical hyperplasia (AH) versus DPEM, simple hyperplasia, or complex hyperplasia was 9.19 (95% CI, 3.87‐21.83).

CONCLUSIONS.

Among women observed for at least 1 year after receiving a biopsy‐based EH diagnosis, EIN and AH were both found to have similarly increased risks of progression to carcinoma. Cancer 2008. © Published 2008 by American Cancer Society
Minimal latency to hippocampal epileptogenesis and clinical epilepsy after perforant pathway stimulation‐induced status epilepticus in awake rats
Authors: Bumanglag Argyle V. , Sloviter Robert S.
Published: August 2008

Hippocampal epileptogenesis is hypothesized to involve secondary mechanisms triggered by initial brain injury. Chemoconvulsant‐induced status epilepticus has been used to identify secondary epileptogenic mechanisms under the assumption that a seizure‐free, preepileptic “latent period” exists that is long enough to accommodate delayed mechanisms. The latent period is difficult to assess experimentally because early spontaneous seizures may be caused or influenced by residual chemoconvulsant that masks the true duration of the epileptogenic process. To avoid the use of chemoconvulsants and determine the latency to hippocampal epileptogenesis and clinical epilepsy, we developed an electrical stimulation‐based method to evoke hippocampal discharges in awake rats and produce hippocampal injury and hippocampal‐onset epilepsy reliably. Continuous video monitoring and granule cell layer recording determined whether hippocampal epileptogenesis develops immediately or long after injury. Bilateral perforant pathway stimulation for 3 hours evoked granule cell epileptiform discharges and convulsive status epilepticus with minimal lethality. Spontaneous stage 3–5 behavioral seizures reliably developed within 3 days poststimulation, and all 72 spontaneous behavioral seizures recorded in 10 animals were preceded by spontaneous granule cell epileptiform discharges. Histological analysis confirmed a reproducible pattern of limited hippocampal and extrahippocampal injury, including an extensive bilateral loss of hilar neurons throughout the hippocampal longitudinal axis. These results indicate that hippocampal epileptogenesis after convulsive status epilepticus is an immediate network defect coincident with neuron loss or other early changes. We hypothesize that the latent period is directly related and inversely proportional to the extent of neuron loss in brain regions involved in seizure initiation, spread, and clinical expression. J. Comp. Neurol. 510:561–580, 2008. © 2008 Wiley‐Liss, Inc.
Distribution and neurochemical characterization of neurons expressing GIRK channels in the rat brain
Authors: del Burgo Laura Saenz , Cortes Roser , Mengod Guadalupe , Zarate Jon , Echevarria Enrique , Salles Joan
Published: August 2008

G‐protein inwardly rectifying potassium (GIRK) channels mediate the synaptic actions of numerous neurotransmitters in the mammalian brain and play an important role in the regulation of neuronal excitability in most brain regions through activation of various G‐protein‐coupled receptors such as the serotonin 5‐HT1Areceptor. In this report we describe the localization of GIRK1, GIRK2, and GIRK3 subunits and 5‐HT1Areceptor in the rat brain, as assessed by immunohistochemistry and in situ hybridization. We also analyze the co‐expression of GIRK subunits with the 5‐HT1Areceptor and cell markers of glutamatergic, γ‐aminobutyric acid (GABA)ergic, cholinergic, and serotonergic neurons in different brain areas by double‐label in situ hybridization. The three GIRK subunits are widely distributed throughout the brain, with an overlapping expression in cerebral cortex, hippocampus, paraventricular nucleus, supraoptic nucleus, thalamic nuclei, pontine nuclei, and granular layer of the cerebellum. Double‐labeling experiments show that GIRK subunits are present in most of the 5‐HT1Areceptor‐expressing cells in hippocampus, cerebral cortex, septum, and dorsal raphe nucleus. Similarly, GIRK mRNA subunits are found in glutamatergic and GABAergic neurons in hippocampus, cerebral cortex, and thalamus, in cholinergic cells in the nucleus of vertical limb of the diagonal band, and in serotonergic cells in the dorsal raphe nucleus. These results provide a deeper knowledge of the distribution of GIRK channels in different cell subtypes in the rat brain and might help to elucidate their physiological roles and to evaluate their potential involvement in human diseases. J. Comp. Neurol. 510:581–606, 2008. © 2008 Wiley‐Liss, Inc.
Neonatal hypoxic/ischemic brain injury induces production of calretinin‐expressing interneurons in the striatum
Authors: Yang Zhengang , You Yan , Levison Steven W.
Published: August 2008

Ischemia‐induced striatal neurogenesis from progenitors in the adjacent subventricular zone (SVZ) in young and adult rodents has been reported. However, it has not been established whether the precursors that reside in the SVZ retain the capacity to produce the full range of striatal neurons that has been destroyed. By using a neonatal rat model of hypoxic/ischemic brain damage, we show here that virtually all of the newly produced striatal neurons are calretinin (CR)‐immunoreactive (+), but not DARPP‐32+, calbindin‐D‐28K+, parvalbumin+, somatostatin+, or choline acetyltransferase+. Retroviral fate‐mapping studies confirm that these newly born CR+ neurons are indeed descendants of the SVZ. Our studies indicate that, although the postnatal SVZ has the capacity to produce a range of neurons, only a subset of this repertoire is manifested in the brain after injury. J. Comp. Neurol. 511:19–33, 2008. © 2008 Wiley‐Liss, Inc.
Informing family approaches to eating disorder prevention: Perspectives of those who have been there
Authors: Loth Katie A. , Neumark‐Sztainer Dianne , Croll Jillian K.
Published: August 2008

Objective:

The study explored how aspects of the family environment may relate to the onset of eating disorders.

Method:

Semi‐structured interviews were conducted with 27 individuals currently receiving treatment for eating disorders. Data were analyzed using principles of content analysis.

Results:

Eight themes emerged regarding recommendations for families to prevent the onset of eating disorders: (1) Enhance parental support; (2) Decrease weight and body talk; (3) Provide a supportive home food environment; (4) Model healthy eating habits and physical activity patterns; (5) Help your children build self‐esteem beyond looks and physical appearance; (6) Encourage appropriate expression of feelings and use of coping mechanisms; (7) Increase your understanding of eating disorder signs and symptoms; and (8) Gain support in dealing appropriately with your own struggles.

Discussion:

Our results can be utilized to generate new theoretical insights as to how parents can raise children with healthy weight‐related attitudes and behaviors. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2009