Affective and evaluative descriptors of pain in the McGill Pain Questionnaire: reduction and reorganization

Recent reports indicate that several descriptors of pain sensations in the McGill Pain Questionnaire (MPQ) are difficult to classify within MPQ sensory subcategories because of incomprehension, underuse, or ambiguity of usage. Adopting the same methodology of recent studies, the present investigation focused on the affective and evaluative subcategories of the MPQ. A decision rule revealed that only 6 of 18 words met criteria for the affective category and 5 of 11 words met criteria for the evaluative category, thus warranting a reduced list of words in these categories. This reduction, however, led to negligible loss of information transmitted. Despite notable changes in classification, the intensity ratings of the retained words correlated very highly with those originally reported for the MPQ. In conclusion, although the intensity ratings of MPQ affective and evaluative descriptors need no revision, selective reduction and reorganization of these descriptors can enhance the efficiency of this approach to pain assessment. [copy ] 2001 by the American Pain Society

Bridge strike reduction: optimising the design of markings

Cases of high-sided vehicles striking low bridges is a large problem in many countries, especially the UK. This paper describes an experiment to evaluate a new design of markings for low bridges. A full size bridge was constructed which was capable of having its overhead clearance adjusted. Subjects sat in a truck cab as. it drove towards the bridge and were asked to judge whether the vehicle could pass safely under the bridge. The main objective of the research, was to determine whether marking the bridge with a newly devised experimental marking would result in more cautious decisions from subjects regarding whether or not the experimental bridge structure could be passed under safely compared with the currently used UK bridge marking standard. The results show that the type of bridge marking influenced the level of caution associated with decisions regarding bridge navigation, with the new marking design producing the most cautious decisions for the two different bridge heights used, at all distances away from the bridge structure. Additionally, the distance before the bridge at which decisions were given had an effect on the level of caution associated with decisions regarding bridge navigation (the closer to the bridge, the more cautious the decisions became, irrespective of the marking design). The implications of these results for reducing the number of bridge strikes are discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.

The DMSO reductase family of microbial molybdenum enzymes; Molecular properties and role in the dissimilatory reduction of toxic elements

The dimethylsulfoxide (DMSO) reductase family of molybdenum enzymes is a large and diverse group that is found in bacteria and archaea. These enzymes are characterised by a bis(molybdopterin guanine dinucleotide)Mo form of the molybdenum cofactor, and they are particularly important in anaerobic respiration including the dissimilatory reduction of certain toxic oxoanions. The structural and phylogenetic relationship between the proteins of this family is discussed. High-resolution crystal structures of enzymes of the DMSO reductase family have revealed a high degree of similarity in tertiary structure. However, there is considerable variation in the structure of the molybdenum active site and it seems likely that these subtle but important differences lead to the great diversity of function seen in this family of enzymes. This diversity of catalytic capability is associated with several distinct pathways of electron transport.

Review of "Clearing the Smoke: Assessing the Science Base for Tobacco Harm Reduction"

Review of Clearing the Smoke: Assessing the Science Base for Tobacco Harm Reductionbby K. STRATTON, P. SHEATHE, R. WALLACE & S. BANDURANT Washington DC, National Academy Press, 2001, xix + 636 pp, US$49.95, ISBN 0309 07282 4 (hbk)

Robust model-order reduction of complex biological processes

This paper addresses robust model-order reduction of a high dimensional nonlinear partial differential equation (PDE) model of a complex biological process. Based on a nonlinear, distributed parameter model of the same process which was validated against experimental data of an existing, pilot-scale BNR activated sludge plant, we developed a state-space model with 154 state variables in this work. A general algorithm for robustly reducing the nonlinear PDE model is presented and based on an investigation of five state-of-the-art model-order reduction techniques, we are able to reduce the original model to a model with only 30 states without incurring pronounced modelling errors. The Singular perturbation approximation balanced truncating technique is found to give the lowest modelling errors in low frequency ranges and hence is deemed most suitable for controller design and other real-time applications. (C) 2002 Elsevier Science Ltd. All rights reserved.

Effect of weight reduction on liver histology and biochemistry in patients with chronic hepatitis C

Background: Steatosis occurs in more than 50% of patients with chronic hepatitis C and is associated with increased hepatic fibrosis. In many of these patients the pathogenesis of steatosis appears to be the some as for patients with non-alcoholic fatty liver disease-that is, related to visceral adiposity and obesity. Methods: The effect of a three month weight reduction programme on liver biochemistry and metabolic parameters was examined in 19 subjects with steatosis and chronic hepatitis C. Paired liver biopsies were performed in 10 subjects, prior to and 3-6 months following the intervention, to determine the effect of weight loss on liver histology. Results: There was a mean weight loss of 5.9 (3.2) kg and a mean reduction in waist circumference of 9.0 (5.0) cm. In 16 of the 19 patients, serum alanine aminotransferase levels fell progressively with weight loss. Mean fasting insulin fell from 16 (7) to 11 (4) mmol/l (p

Adaptation of rainbow fish to lake and stream habitats

Fish occupy a range of hydrological habitats that exert different demands on locomotor performance. We examined replicate natural populations of the rainbow fishes Melanotaenia eachamensis and M. duboulayi to determine if colonization of low-velocity (lake) habitats by fish from high-velocity (stream) habitats resulted in adaptation of locomotor morphology and performance. Relative to stream conspecifics, lake fish had more posteriorly positioned first dorsal and pelvic fins, and shorter second dorsal fin bases. Habitat dimorphism observed between wild-caught fish was determined to be heritable as it was retained in M. eachamensis offspring raised in a common garden. Repeated evolution of the same heritable phenotype in independently derived populations indicated body shape divergence was a consequence of natural selection. Morphological divergence between hydrological habitats did not support a priori expectations of deeper bodies and caudal peduncles in lake fish. However, observed divergence in fin positioning was consistent with a family-wide association between habitat and morphology, and with empirical studies on other fish species. As predicted, decreased demand for sustained swimming in takes resulted in a reduction in caudal red muscle area of lake fish relative to their stream counterparts. Melanotaenia duboulayi lake fish also had slower sustained swimming speeds (U-crit) than stream conspecifics. In M. eachamensis, habitat affected U-crit of males and females differently. Specifically, females exhibited the pattern observed in M. duboulayi (lake fish had faster U-crit than stream fish), but the opposite association was observed in males (stream males had slower Ucrit than lake males). Stream M. eachamensis also exhibited a reversed pattern of sexual dimorphism in U-crit (males slower than females) relative to all other groups (males faster than females). We suggest that M. eachamensis males from streams responded to factors other than water velocity. Although replication of muscle and U,,it phenotypes across same habitat populations within and/or among species was suggestive of adaptation, the common garden experiment did not confirm a genetic basis to these associations. Kinematic studies should consider the effect of the position and base length of dorsal fins.

A randomized trial of aggressive lipid reduction for improvement of myocardial ischemia, symptom status, and vascular function in patients with coronary artery disease not amenable to intervention

PURPOSE: To determine the effects of aggressive lipid lowering on markers of ischemia, resistance vessel function, atherosclerotic burden, and Symptom status in patients with symptomatic coronary artery disease. METHODS: Sixty consecutive patients with coronary artery disease that was unsuitable for revascularization were assigned randomly to either usual therapy of lipids for patients with a low-density lipoprotein (LDL) cholesterol target level <116 mg/dL, or to a, more aggressive lipid-lowering strategy involving up to 80 mg/d of atorvastatin, with a target LDL cholesterol level <77 mg/dL. The extent and severity of inducible ischemia (by dobutamine echocardiography), vascular function.(brachial artery reactivity), atheroma burden (carotid intima-media thickness), and symptom status were evaluated blindly at baseline and after 12 weeks of treatment. RESULTS: After 12 weeks of treatment, patients in the aggressive therapy group had a significantly greater decrease in mean (+/- SD) LDL cholesterol level than those in the usual care group (29 +/- 38 mg/dL vs. 7 +/- 24 mg/dL, P = 0.03). Patients in the aggressive therapy group had a reduction in the number of ischemic wall segments (mean between-group difference of 1.3; 95% confidence interval: 0.1 to 2.0; P = 0.04), flow-mediated dilatation (mean between-group difference of 5.9%; 95% confidence interval: 2.5% to 9.4%; P = 0.001), and angina score after 12 weeks. There were no significant changes in atherosclerotic burden in either group. CONCLUSION: Patients with symptomatic coronary artery disease who are treated with aggressive lipid lowering have improvement of symptom status and ischemia that appears to reflect improved vascular function but not atheroma burden. Am J Med. 2003;114:445-453. (C) 2003 by Excerpta Medica Inc.

Independent contribution of plaque complexity to myocardial ischemia during Dobutamine stress echocardiography

The influence of complex plaque morphology on the extent of demand-induced ischemia in unselected patients is not well defined. We sought to investigate the functional significance of lesion morphology in patients who underwent coronary angiography and dobutamine stress echocardiography (DSE).,Angiography and DSE were performed within a 6-month period (mean 1 +/- 1 month) in 196 patients. Angiographic assessments involved quantification of stenosis severity, assessment of the extent of jeopardized myocardium, and categorization of plaque morphology according to the Ambrose classification. DSE was interpreted by separate investigators with respect to wall motion score index (WMSI) and number of coronary territories involved. A general linear model was constructed to assess,the independent contribution of patient characteristics and angiographic and DSE results with respect to extent of ischemic myocardium. Complex lesion morphology was seen in 62 patients (32%). Patients with complex lesions were more likely to have had prior myocardial infarction (p < 0.001) and be current smokers (p = 0.03). During angiography, they exhibited a trend toward a greater number of diseased vessels, had a greater coronary jeopardy score (p < 0.001) and more frequent collateral flow (p = 0.03). During echocardiography, patients had a higher stress WMSI (p < 0.001) and were more likely to show ischemia in all 3 arterial territories (p < 0.01). On multivariate regression, the coronary artery jeopardy score and the presence of complex plaque morphology were independent predictors of the extent of ischemic myocardium (R 2 = 34%, p < 0.001). Thus, patients with complex plaque morphology are older, more likely to smoke, and more likely to have had prior myocardial. infarction. They exhibit more extensive disease with higher coronary jeopardy scores and a higher resting and peak stress WMSI. Despite these differences, complex plaque morphology remains an independent predictor of the extent of ischemia during stress. (C) 2003 by Excerpta Medica, Inc.

A política antidrogas brasileira : velhos dilemas

O debate atual sobre drogas tem sido organizado em torno de discursos científicos que tendem a configurar a questão ora como problema de segurança pública (relacionado ao tráfico e à repressão), ora como problema de saúde pública (relacionado à repressão da demanda por um lado e à redução de danos por outro). O presente texto traz uma reflexão que busca configurar como a política de enfrentamento às drogas no Brasil enseja em suas proposições uma luta entre as lógicas de segurança pública e de saúde pública expressas no embate entre as duas políticas instituídas pelo governo brasileiro no enfrentamento à questão – a política nacional antidrogas regulamentada em 2003 pela Secretaria Nacional Antidrogas (estrutura criada no governo Fernando Henrique Cardoso – FHC - por meio da medida provisória nº 1669, de 1998, e modificada no governo Lula para "Política Pública Sobre Drogas") e a Política de Atenção Integral ao Usuário de Álcool e Drogas do Ministério da Saúde (também formulada no governo FHC)

Cobertura permanente de solo com leguminosas herbáceas perenes no cultivo de bananeiras no médio Vale do Jequitinhonha

A região da Caatinga é caracterizada pelas altas temperaturas durante o ano e má distribuição das chuvas. Em virtude desses fatores de clima regional, tem-se a necessidade de adoção por práticas que elevem à eficiência e sustentabilidade agrícola local. Assim, objetivou-se avaliar a aptidão de leguminosas herbáceas perenes como cobertura permanente de solo no cultivo de bananeira. Foram conduzidos três experimentos, para avaliação das leguminosas, utilizou-se um delineamento experimental em blocos casualizados, com quatro repetições, em esquema de parcelas subdivididas no espaço e para algumas variáveis, sub-subdividida no tempo, sendo: Fator “A” os dois diferentes ambientes de plantio: municípios de Itaobim/MG e Virgem da Lapa/MG; Fator “B”, nas subparcelas, dois manejos de cobertura do solo e para algumas variáveis, três manejos, constituídos pelas leguminosas: cudzu tropical (Pueraria phaseoloides) calopogônio (Calopogonium mucunoides) e solo descoberto (solo capinado); Fator “C” épocas de coleta de dados. Para avaliação das bananeiras, foram dois experimentos em blocos casualizados, com quatro repetições, em esquema de parcelas sudivididas no espaço, sendo: nas parcelas, fator “A” constituído por três manejos de cobertura do solo, pelas leguminosas: cudzu tropical e o calopogônio, e solo descoberto (solo capinado); fator “B”, nas subparcelas, plantas de bananeiras em três idades morfofisiológicas (diferentes ciclos e tamanhos); Para algumas variáveis que foram submetidas a coletas periódicas, utilizou-se o esquema de parcelas subsubdivididas no tempo, acrescentando-se o fator “C”, datas das coletas nas sub-subparcelas, tendo como referência os dias após semeadura (DAS) das leguminosas. Foram avaliadas as seguintes variáveis: taxa de cobertura do solo; potencial de deposição de folhas e a ciclagem de nutrientes; capacidade de inibição da vegetação espontânea; conservação da temperatura e promoção da retenção de umidade do solo. Também foi avaliado o crescimento vegetativo e produtividade das bananeiras. Como resultados principais, notou-se que as leguminosas proporcionaram eficiente cobertura do solo, o calopogônio apresentou o maior acúmulo de N, P, K, e Ca, via deposição de material senescente, tal como maior inibição das plantas espontâneas nos pomares de bananeiras. Essa cobertura também promoveu uma eficiente redução da temperatura do solo, possibilitando menor variação térmica nas camadas de maior concentração radicular da bananeira, e consequentemente, obtendo maior acúmulo de umidade no solo. As bananeiras cultivadas sobre coberturas vivas de solo apresentaram aumento gradativo no crescimento e peso de cacho. Os resultados reforçam o potencial uso dessas espécies na fruticultura, principalmente em regiões de severas restrições hídricas, como forma de adubação e otimização de diversos processos biológicos em seu ambiente de cultivo.

Modelo matemático para planejamento da circulação de trens em uma ferrovia de linha singela

Diversos fatores têm contribuído para o aumento da demanda por transporte ferroviário no Brasil. Dentre eles, citam-se: o aumento das exportações brasileiras nos últimos anos e a aprovação do novo marco regulatório para o setor ferroviário brasileiro que permitiu o uso da capacidade ociosa das ferrovias e o compartilhamento da malha por diversos operadores. Investimentos para construção de novas ferrovias e melhorias nas já existentes são muito elevados, o que dificulta a implantação de novos projetos. Assim, faz-se necessário melhorar o planejamento da circulação de trens visando o aumento de capacidade sem a necessidade de novos investimentos, otimizando o uso da estrutura já existente. Esta dissertação tem como objetivo propor um modelo matemático para realizar o planejamento da circulação de trens em uma ferrovia de linha singela, que minimize o transit time, isto é, o tempo total de viagem de todos os trens e consequentemente reduza o tempo parado em pátios de cruzamento. O modelo proposto permite que os trens sejam atrasados ou adiantados na partida visando reduzir o tempo parado em pátios de cruzamento. O modelo é resolvido de forma ótima usando o solver CPLEX 12.6. Foram realizados testes com dados reais da Ferrovia Centro Atlântica (FCA) e os resultados alcançados pelo CPLEX foram comparados com os resultados do planejamento manual da FCA. O modelo obteve redução do tempo de viagem dos trens em todos os cenários testados.