105 research outputs found
Assessing students' experiences of teaching-learning environments and approaches to learning.:Validation of a questionnaire used in different countries and varying contexts.
ERGONOMIA E SEGURANÇA EM ATIVIDADES EXTRATIVISTAS NO ESTADO DO ACRE
A ergonomia é a ciência que estuda a adaptação do trabalho ao homem, tendo como objetivo a melhoria das condições de saúde, segurança e bem estar do trabalhador. Apesar de existirem diversos estudos de ergonomia em vários setores, ao que tange atividades extrativistas, ainda são poucas as informações obtidas. Esta pesquisa teve como objetivo analisar e compreender as condições de trabalho, saúde e segurança das atividades na coleta e transporte de castanha e açaí na Reserva Extrativista Cazumbá - Iracema no Estado do Acre, a fim de propor sugestões à referida categoria a partir da análise dos fatores ergonômicos. As variáveis analisadas foram os fatores humanos, ambientais (clima e iluminação), carga física, posturas adotadas e o manuseio de cargas. Foram avaliados ao total 40 trabalhadores. De acordo com os resultados, os trabalhadores tinham idade média de 35 anos, peso médio de 69 kg, baixo índice de analfabetismo (2,3%), de origem predominantemente rural (94,1%), tendo um consumo alto de bebidas alcoólicas (49%) e tabaco (15%). A maioria dos trabalhadores já tiveram acidentes em suas atividades. A exposição ao calor e a iluminância foram considerados elevados e inadequados entre os horários de 12 e 13:30 horas. A carga física foi considerada moderadamente pesada na maioria das operações, destacando-se o transporte de castanha e a coleta do açai, sendo considerados pesados. As posturas mais prejudiciais foram observadas na coleta do açaí e no transporte de castanha. O manuseio de cargas apresentou alto risco de lesão nas atividades de transporte de castanha. Para melhoria das condições de trabalho, saúde, bem estar e segurança, deve haver uma conscientização a fim de diminuir os vícios e fiscalização para que haja o uso devido dos equipamentos de proteção individual. Ainda assim, os trabalhadores devem ser treinados e conscientizados para utilizar medidas adequadas de controle onde os níveis de exposição a iluminância são elevados. Também necessita-se de adoção de tempo de repouso por hora efetiva de trabalho nas atividades de coleta do açaí e transporte de castanha. A fim de evitar danos a coluna do trabalhador, é necessário a adoção de pausas durante as atividades de coleta e transporte de ambas as cadeias analisadas. E com relação ao manuseio de cargas é necessária uma reorganização ergonômica a fim de reduzir o peso manuseado para execução da atividade de transporte de castanha.
Palavra - chave: Processo Produtivo, Unidades de Conservação, Condições de Trabalho
Suppression of superconductivity by non-magnetic disorder in organic superconductor -(BEDT-TTF)Cu(NCS)
The suppression of superconductivity by nonmagnetic disorder is investigated
systematically in the organic superconductor
-(BEDT-TTF)Cu(NCS). We introduce a nonmagnetic disorder arising
from molecule substitution in part with deuterated BEDT-TTF or BMDT-TTF for
BEDT-TTF molecules and molecular defects introduced by X-ray irradiation. A
quantitative evaluation of the scattering time is carried out
by de Haas-van Alphen (dHvA) effect measurement. A large reduction in with a linear dependence on is found in the
small-disorder region below 1 10
s in both the BMDT-TTF molecule-substituted and X-ray-irradiated
samples. The observed linear relation between and is in agreement with the Abrikosov-Gorkov (AG) formula, at least in the
small-disorder region. This observation is reasonably consistent with the
unconventional superconductivity proposed thus far for the present organic
superconductor. A deviation from the AG formula, however, is observed in the
large-disorder region above 1 10
s, which reproduces the previous transport study (J. G. Analytis {\it et
al.}: Phys. Rev. Lett. {\bf 96} (2006) 177002). We present some interpretations
of this deviation from the viewpoints of superconductivity and the inherent
difficulties in the evaluation of scattering time.Comment: 11 pages, 6 figure
A review of the benefits and drawbacks to virtual field guides in today’s Geoscience higher education environment
Virtual Field Guides are a way for educators to tackle the growing issue of funding pressures in areas of higher education, such as geography. Virtual Field Guides are however underutilised and can offer students a different way of learning. Virtual Field Guides have many benefits to students, such as being more inclusive, building student skills and confidence in a controlled environment pre fieldtrip and can increase engagement in the topic studied. There are also benefits to the educator, such as reduced cost, more efficient students on fieldwork tasks and the ability to tailor and update their field guides to suit their needs. However there are drawbacks in the challenge of creation and their outcome as educational standalone tools. This paper reviews the literature around the benefits and draw backs to the creation and incorporation of virtual field guides in geoscience education. © 2017, The Author(s)
Effects of Subthalamic Nucleus Lesions and Stimulation upon Corticostriatal Afferents in the 6-Hydroxydopamine-Lesioned Rat
Abnormalities of striatal glutamate neurotransmission may play a role in the pathophysiology of Parkinson's disease and may respond to neurosurgical interventions, specifically stimulation or lesioning of the subthalamic nucleus (STN). The major glutamatergic afferent pathways to the striatum are from the cortex and thalamus, and are thus likely to be sources of striatal neuronally-released glutamate. Corticostriatal terminals can be distinguished within the striatum at the electron microscopic level as their synaptic vesicles contain the vesicular glutamate transporter, VGLUT1. The majority of terminals which are immunolabeled for glutamate but are not VGLUT1 positive are likely to be thalamostriatal afferents. We compared the effects of short term, high frequency, STN stimulation and lesioning in 6-hydroxydopamine (6OHDA)-lesioned rats upon striatal terminals immunolabeled for both presynaptic glutamate and VGLUT1. 6OHDA lesions resulted in a small but significant increase in the proportions of VGLUT1-labeled terminals making synapses on dendritic shafts rather than spines. STN stimulation for one hour, but not STN lesions, increased the proportion of synapses upon spines. The density of presynaptic glutamate immuno-gold labeling was unchanged in both VGLUT1-labeled and -unlabeled terminals in 6OHDA-lesioned rats compared to controls. Rats with 6OHDA lesions+STN stimulation showed a decrease in nerve terminal glutamate immuno-gold labeling in both VGLUT1-labeled and -unlabeled terminals. STN lesions resulted in a significant decrease in the density of presynaptic immuno-gold-labeled glutamate only in VGLUT1-labeled terminals. STN interventions may achieve at least part of their therapeutic effect in PD by normalizing the location of corticostriatal glutamatergic terminals and by altering striatal glutamatergic neurotransmission
Tuberculosis and HIV Co-Infection
Tuberculosis (TB) and HIV co-infections place an immense burden on health care systems and pose particular diagnostic and therapeutic challenges. Infection with HIV is the most powerful known risk factor predisposing for Mycobacterium tuberculosis infection and progression to active disease, which increases the risk of latent TB reactivation 20-fold. TB is also the most common cause of AIDS-related death. Thus, M. tuberculosis and HIV act in synergy, accelerating the decline of immunological functions and leading to subsequent death if untreated. The mechanisms behind the breakdown of the immune defense of the co-infected individual are not well known. The aim of this review is to highlight immunological events that may accelerate the development of one of the two diseases in the presence of the co-infecting organism. We also review possible animal models for studies of the interaction of the two pathogens, and describe gaps in knowledge and needs for future studies to develop preventive measures against the two diseases
Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model
We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095%=3.47×10-25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering. © 2019 American Physical Society
Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model
We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO’s second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h95%0=3.47×10−25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering
Absence of fine structure in the photoemission spectrum of the icosahedral Al-Pd-Mn quasicrystal
Differential White Blood Cell Count and Type 2 Diabetes: Systematic Review and Meta-Analysis of Cross-Sectional and Prospective Studies
Objective: Biological evidence suggests that inflammation might induce type 2 diabetes (T2D), and epidemiological studies have shown an association between higher white blood cell count (WBC) and T2D. However, the association has not been systematically investigated.Research Design and Methods: Studies were identified through computer-based and manual searches. Previously unreported studies were sought through correspondence. 20 studies were identified (8,647 T2D cases and 85,040 non-cases). Estimates of the association of WBC with T2D were combined using random effects meta-analysis; sources of heterogeneity as well as presence of publication bias were explored.Results: The combined relative risk (RR) comparing the top to bottom tertile of the WBC count was 1.61 (95% CI: 1.45; 1.79, p = 1.5*10(-18)). Substantial heterogeneity was present (I-2 = 83%). For granulocytes the RR was 1.38 (95% CI: 1.17; 1.64, p = 1.5*10(-4)), for lymphocytes 1.26 (95% CI: 1.02; 1.56, p = 0.029), and for monocytes 0.93 (95% CI: 0.68; 1.28, p = 0.67) comparing top to bottom tertile. In cross-sectional studies, RR was 1.74 (95% CI: 1.49; 2.02, p = 7.7*10(-13)), while in cohort studies it was 1.48 (95% CI: 1.22; 1.79, p = 7.7*10(-5)). We assessed the impact of confounding in EPIC-Norfolk study and found that the age and sex adjusted HR of 2.19 (95% CI: 1.74; 2.75) was attenuated to 1.82 (95% CI: 1.45; 2.29) after further accounting for smoking, T2D family history, physical activity, education, BMI and waist circumference.Conclusions: A raised WBC is associated with higher risk of T2D. The presence of publication bias and failure to control for all potential confounders in all studies means the observed association is likely an overestimate
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