Calculation of bound and resonance states of HO2 for nonzero total angular momentum

Bound and resonance states of HO2 have been calculated quantum mechanically by the Lanczos homogeneous filter diagonalization method [Zhang and Smith, Phys. Chem. Chem. Phys. 3, 2282 (2001); J. Chem. Phys. 115, 5751 (2001)] for nonzero total angular momentum J = 1,2,3. For lower bound states, agreement between the results in this paper and previous work is quite satisfactory; while for high lying bound states and resonances these are the first reported results. A helicity quantum number V assignment (within the helicity conserving approximation) is performed and the results indicate that for lower bound states it is possible to assign the V quantum numbers unambiguously, but for resonances it is impossible to assign the V helicity quantum numbers due to strong mixing. In fact, for the high-lying bound states, the mixing has already appeared. These results indicate that the helicity conserving approximation is not good for the resonance state calculations and exact quantum calculations are needed to accurately describe the reaction dynamics for HO2 system. Analysis of the resonance widths shows that most of the resonances are overlapping and the interferences between them lead to large fluctuations from one resonance to another. In accord with the conclusions from earlier J = 0 calculations, this indicates that the dissociation of HO2 is essentially irregular. (C) 2003 American Institute of Physics.

Simultaneous observations of ionospheric quasiperiodic scintillations from short and long meridional baselines using VHF transmissions from transit satellites

For the first time it was possible to observe regular quasiperiodic scintillations (QPS) in VHF radio-satellite transmissions from orbiting satellites simultaneously at short (2.1 km) and long (121 km) meridional baselines in the vicinity of a typical mid-latitude station (Brisbane; 27.5degreesS and 152.9degreesE geog. and 35.6degrees invar.lat.), using three sites (St. Lucia-S, Taringa-T in Brisbane and Boreen Pt.-B, north of Brisbane). A few pronounced quasiperiodic (QP) events were recorded showing unambiguous regular structures at the sites which made it possible to deduce a time displacement of the regular fading minimum at S, T and B. The QP structure is highly dependent on the geometry of the ray-path from a satellite to the observer which is manifested as a change of a QP event from symmetrical to non-symmetrical for stations separated by 2.1 km, and to a radical change in the structure of the event over a distance of 121 km. It is suggested the short-duration intense QP events are due to a Fresnel diffraction (or a reflection mechanism) of radio-satellite signals by a single ionospheric irregularity in a form of an ellipsoid with a large ionization gradient along the major axis. The structure of a QP event depends on the angle of viewing of the irregular blob from a radio-satellite. In view of this it is suggested that the reported variety of the ionization formation, responsible for different types of QPS, is only apparent but not real. (C) 2003 Elsevier Science Ltd. All rights reserved.

Transporte de trabalhadores rurais: parceria para uma nova realidade

Parceria concebida pela DRT-GO que envolve as Pol??cias Rodovi??rias com outros ??rg??os do governo e entidades sindicais, para equacionar problemas existentes no transporte de trabalhadores rurais devido ?? falta de fiscaliza????o. As Pol??cias Rodovi??rias Federal e Estadual assumiram a fiscaliza????o e o controle do transporte de trabalhadores em todo o estado. Foram reduzidas as den??ncias de transporte irregular de trabalhadores rurais. A incid??ncia de mortes ou invalidez por acidentes de trajeto devido ao transporte irregular dos trabalhadores foi praticamente eliminada no Estado

Incidência de alterações estruturais das pregas vocais associadas ao pólipo de prega vocal

A etiologia mais aceita para pólipos de pregas vocais é o fonotrauma. Imaginamos que possa existir alguma alteração anatômica prévia nas pregas vocais que predisponha indivíduos a apresentarem lesões fonotraumáticas. OBJETIVO: O presente estudo retrospectivo procura encontrar correlação entre os pólipos de prega vocal e alterações estruturais da prega vocais. MATERIAL E MÉTODO: Foi realizado trabalho retrospectivo a partir da descrição cirúrgica de 33 pacientes submetidos a exérese de pólipo de prega vocal no período de três anos em hospital universitário. RESULTADOS: Trinta e um pacientes apresentaram pólipos unilaterais e 2 bilaterais. Foram encontradas 27 lesões associadas: 10 lesões reacionais, 12 sulcos, 3 cistos e 2 ectasia capilars. Foram 14 lesões contralaterais e 13 ipsilaterais. DISCUSSÃO E CONCLUSÕES: Encontrou-se uma forte correlação entre a presença de uma lesão de base influindo como co-fator de fragilização da prega vocal ao fonotrauma, pois das 27 lesões encontradas 17 foram consideradas pré-existentes (63%). As lesões poderiam interferir na coaptação das pregas vocais, gerando uma onda mucosa irregular durante a fonação, expondo o espaço de Reinke a uma agressão estrutural. Apesar do caráter preliminar do trabalho os achados sugerem íntima correlação entre o pólipo e lesões estruturais mínimas das pregas vocais.

Monitoração do ambiente externo: uma necessidade para as organizações tecnológicas

Vários sinais evidentes no mundo de hoje indicam que a organização moderna, funcionando na fronteira da tecnologia, não pode mais confiar em métodos intuitivos e não-sistemáticos de agrupar e analisar informação necessária para o gerenciamento estratégico de suas operações. Enquanto os padrões de sinais que levam a esta conclusão estão se tornando mais evidentes todos os dias, a resposta organizacional a este desafio ainda é altamente irregular e freqüentemente irracional. A grande maioria das organizações só pratica a forma não-estruturada de observação (Monitoração Panorámica Informal), para monitorar seu ambiente externo. A recente onda de atividades em empresas tecnológicas, institutos de P&D e órgãos governamentais, para melhor acompanhar as mudanças bruscas e rápidas em seu ambiente externo, é indicativa da crescente tendência de se praticarem formas mais sofisticadas de MA. O objetivo deste trabalho foi o de desenvolver a conceituação do processo de MA dentro do contexto de planejamento estratégico e indicar, com base em uma revisão da literatura e na experiência do autor, como esta atividade pode ser estruturada dentro da organização. Devido à ampla gama de variáveis organizacionais influenciando o desenvolvimento de um sistema de MA, apenas diretrizes gerais puderam ser apresentadas. Entretanto, espera-se que este material venha a ajudar organizações interessadas a entenderem as opções disponíveis e derivarem uma solução compatível com suas atividades e recursos.

A descentralização na vigilância sanitária: trajetória e descompasso

O presente trabalho descreve características do processo de descentralização no Sistema Único de Saúde (SUS) e na vigilância sanitária, quanto à relação entre as esferas de gestão: centralização e descentralização. Utilizou-se uma abordagem analítica com foco na relação entre as esferas governamentais como fator constitutivo da gestão de uma política social. Os resultados indicam que a vigilância sanitária desenvolveu um processo lento e irregular de descentralização, que expressa um claro descompasso com o mesmo processo no SUS, em relação à estrutura institucional, estratégias de pactuação e relação entre as esferas. Conclui-se que as dificuldades enfrentadas no processo de descentralização estão relacionadas também às tensões advindas de diferentes projetos políticos que coexistem nesses espaços institucionais.

Novo encontro do Trypanosoma (Megatrypanum) freitasi, parasita do gambá

Relata-se um novo encontro do Trypanosoma (Megatrypanum) freitasi, raro tripanosomatídeo encontrado no sangue de marsupiais, do gênero Didelphis. Salientam-se a baixa e irregular parasitemia observada, as dificuldades no isolamento, bem como, o concomitante achado do T. cruzi.

Prevalencia del alcoholismo durante tres décadas en Chile (1952-1982)

Mediante el método de Jellinek se estudió la evolución del número de alcohólicos y de la tasa de prevalencia de alcoholismo en Chile y sus variaciones entre los años 1952 y 1982. Se señalan los sesgos y limitaciones de la metodología empleada y se comparan los resultados obtenidos con los de otras investigaciones chilenas. Se concluye que ha habido un incremento del número de alcohólicos y de la tasa de alcoholismo en el periodo analizado que para 1982 es un 70% mayor que para 1952. Este incremento ha sido irregular y fluctuante. Nuestros resultados cuestionan la eficacia de las políticas de prevención del alcoholismo llevadas a cabo en el período.

Observações sobre domiciliação de mosquitos Culex (Melanoconion), em ambiente com acentuadas modificações antrópicas

Estudam-se alguns aspectos do comportamento de espécies de Culex (Melanoconion) em ambiente antrópico intensamente modificado. Foram realizadas coletas mensais de adultos, concomitantes e levadas a efeito no peridomicílio, em área aberta e em área coberta por vegetação de segunda formação. Foram focalizadas as espécies dominantes e representadas por Cx. delpontei, Cx. ocossa, Cx. ribeirensis, Cx. sacchettae e Cx. taeniopus. No peridomicílio, destacam-se pela regularidade de sua presença, Cx. ribeirensis e Cx. sacchettae, incluindo apreciável comparecimento às coletas com isca humana ali realizadas. A época de maior rendimento das capturas correspondeu ao primeiro trimestre, em especial modo, ao mês de março. Aliado a esse aspecto, Cx. ribeirensis e Cx. sacchettae revelaram apreciável freqüência à isca humana. Em relação a esta, o menor comparecimento foi apresentado por Cx. delpontei e Cx. ocossa. Quanto a Cx. taeniopus, compareceu de maneira um tanto irregular e em número geralmente inferior ao dos demais. As observações evidenciaram curva de atividade aumentando rapidamente por ocasião do início da noite e mantendo-se durante todo o período noturno, apresentada por Cx. ribeirensis, Cx. sacchettae e Cx. taeniopus. O outro tipo de curva foi observado com Cx. delpontei e Cx. ocossa, com aumento gradual na primeira metade da noite, alcançando o máximo ao redor da meia-noite, e declinando sensivelmente na segunda metade do período. As coletas de formas imaturas permitiram evidenciar criadouros de Cx. delpontei em cursos de água de porte médio ou grande, e associados à vegetação aquática flutuante. São feitas considerações de ordem ecológica passíveis de interpretar esses comportamentos de interesse epidemiológico.

On the concept of endogenous volatility

Most financial and economic time-series display a strong volatility around their trends. The difficulty in explaining this volatility has led economists to interpret it as exogenous, i.e., as the result of forces that lie outside the scope of the assumed economic relations. Consequently, it becomes hard or impossible to formulate short-run forecasts on asset prices or on values of macroeconomic variables. However, many random looking economic and financial series may, in fact, be subject to deterministic irregular behavior, which can be measured and modelled. We address the notion of endogenous volatility and exemplify the concept with a simple business-cycles model.

Femtosecond laser ablation of dentin

The surface morphology, structure and composition of human dentin treated with a femtosecond infrared laser (pulse duration 500 fs, wavelength 1030 nm, fluences ranging from 1 to 3 J cm(-2)) was studied by scanning electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The average dentin ablation threshold under these conditions was 0.6 +/- 0.2 J cm(-2) and the ablation rate achieved in the range 1 to 2 mu m/pulse for an average fluence of 3 J cm(-2). The ablation surfaces present an irregular and rugged appearance, with no significant traces of melting, deformation, cracking or carbonization. The smear layer was entirely removed by the laser treatment. For fluences only slightly higher than the ablation threshold the morphology of the laser-treated surfaces was very similar to the dentin fracture surfaces and the dentinal tubules remained open. For higher fluences, the surface was more porous and the dentin structure was partially concealed by ablation debris and a few resolidified droplets. Independently on the laser processing parameters and laser processing method used no sub-superficial cracking was observed. The dentin constitution and chemical composition was not significantly modified by the laser treatment in the processing parameter range used. In particular, the organic matter is not preferentially removed from the surface and no traces of high temperature phosphates, such as the beta-tricalcium phosphate, were observed. The achieved results are compatible with an electrostatic ablation mechanism. In conclusion, the high beam quality and short pulse duration of the ultrafast laser used should allow the accurate preparation of cavities, with negligible damage of the underlying material.

El estrato socioeconómico como factor predictor del uso constante de condón en adolescentes

OBJETIVO: El estrato socioeconómico juega un rol importante en las desigualdades en salud. En México, la prevalencia más alta de casos de SIDA se encuentra en población de estratos más bajos. El propósito de lo estudio fue describir el estrato socioeconómico (ajustado por variables psicosociales, situacionales y demográficas) como un factor predictor del uso consistente del condón, en adolescentes. MÉTODOS: Se incluyó en el estudio una muestra de una encuesta previa aplicada a 1.410 adolescentes de 15 a 19 años y estratificada por edad, género y estrato socioeconómico de Guadalajara, México. El análisis fue aplicado sobre los 251 adolescentes que reportaron actividad sexual. El análisis estadístico se realizó mediante Ji Cuadrada, t-test, ANOVA y regresión logística. RESULTADOS: La frecuencia de uso consistente de condón fue 30,7% y hubo una prevalencia de uso irregular. El estrato socioeconómico alto fue el principal predictor (OR= 11,1, CI95%= 2,6-47,6). Otros predictores significativos fueron el género masculino, el soporte de los pares y el nivel alto de conocimientos sobre VIH/SIDA. CONCLUSIÓN: El estrato socioeconómico es un importante factor predictor del uso consistente del condón.

Working hours, work-life conflict and health in precarious and "permanent" employment

OBJECTIVE: The expansion of precarious employment in OECD countries has been widely associated with negative health and safety effects. Although many shiftworkers are precariously employed, shiftwork research has concentrated on full-time workers in continuing employment. This paper examines the impact of precarious employment on working hours, work-life conflict and health by comparing casual employees to full-time, "permanent" employees working in the same occupations and workplaces. METHODS: Thirty-nine convergent interviews were conducted in two five-star hotels. The participants included 26 full-time and 13 casual (temporary) employees. They ranged in age from 19 to 61 years and included 17 females and 22 males. Working hours ranged from zero to 73 hours per week. RESULTS: Marked differences emerged between the reports of casual and full-time employees about working hours, work-life conflict and health. Casuals were more likely to work highly irregular hours over which they had little control. Their daily and weekly working hours ranged from very long to very short according to organisational requirements. Long working hours, combined with low predictability and control, produced greater disruption to family and social lives and poorer work-life balance for casuals. Uncoordinated hours across multiple jobs exacerbated these problems in some cases. Health-related issues reported to arise from work-life conflict included sleep disturbance, fatigue and disrupted exercise and dietary regimes. CONCLUSIONS:This study identified significant disadvantages of casual employment. In the same hotels, and doing largely the same jobs, casual employees had less desirable and predictable work schedules, greater work-life conflict and more associated health complaints than "permanent" workers.

Can varying the number of teams in a shift schedule constitute a preventive strategy?

OBJECTIVE: The study examines the implications for shiftworkers of applying different numbers of teams in the organization of shiftwork. METHODS: The participating operators came from five different companies applying continuous shift rotation systems. The companies shared the same product organization and a common corporate culture belonging to the same multinational company. Each company had a shift system consisting of four, five or six teams, with the proportion of shifts outside day work decreasing as the number of teams increased. Questionnaire and documentary data were used as data sources. RESULTS: Operators in systems with additional teams had more daywork but also more irregular working hours due to both overtime and schedule changes. Operators using six teams used fewer social compensation strategies. Operators in four teams were most satisfied with their work hours. Satisfaction with the time available for various social activities outside work varied inconsistently between the groups. CONCLUSIONS: In rotating systems the application of more teams reduces the number of shifts outside day work. This apparent improvement for shiftworkers was counteracted by a concomitant irregularity produced by greater organizational requirements for flexibility. The balance of this interaction was found to have a critical impact on employees.

Linking better shiftwork arrangements with safety and health management systems

OBJECTIVE: Various support measures useful for promoting joint change approaches to the improvement of both shiftworking arrangements and safety and health management systems were reviewed. A particular focus was placed on enterprise-level risk reduction measures linking working hours and management systems. METHODS: Voluntary industry-based guidelines on night and shift work for department stores and the chemical, automobile and electrical equipment industries were examined. Survey results that had led to the compilation of practicable measures to be included in these guidelines were also examined. The common support measures were then compared with ergonomic checkpoints for plant maintenance work involving irregular nightshifts. On the basis of this analysis, a new night and shift work checklist was designed. RESULTS: Both the guidelines and the plant maintenance work checkpoints were found to commonly cover multiple issues including work schedules and various job-related risks. This close link between shiftwork arrangements and risk management was important as shiftworkers in these industries considered teamwork and welfare services to be essential for managing risks associated with night and shift work. Four areas found suitable for participatory improvement by managers and workers were work schedules, ergonomic work tasks, work environment and training. The checklist designed to facilitate participatory change processes covered all these areas. CONCLUSIONS: The checklist developed to describe feasible workplace actions was suitable for integration with comprehensive safety and health management systems and offered valuable opportunities for improving working time arrangements and job content together.