1,006 research outputs found
Načelo utvrđivanja rizika
The Precautionary Principle in its simplest form states: "When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause-and-effect relationships are not fully established scientifically". This Principle is the basis for European environmental law, and plays an increasing role in developing environmental health policies as well. It also is used in environmental decision-making in Canada and in several European countries, especially in Denmark, Sweden, and Germany. The Precautionary Principle has been used in the environmental decision-making process and in regulating drugs and other consumer products in the United States. The Precautionary Principle enhances the collection of risk information for, among other items, high production volume chemicals and risk-based analyses in general. It does not eliminate the need for good science or for science-based risk assessments. Public participation is encouraged in both the review process and the decision-making process. The Precautionary Principle encourages, and in some cases may require, transparency of the risk assessment process on health risk of chemicals both for public health and the environment. A debate continues on whether the Principle should embrace the "polluter pays" directive and place the responsibility for providing risk assessment on industry. The best elements of a precautionary approach demand good science and challenge the scientific community to improve methods used for risk assessment.Načelo utvrđivanja rizika u svojem najjednostavnijem obliku glasi: "Kad radnja povećava opasnost za ljudsko zdravlje ili okoliš, trebale bi biti poduzete mjere opreza iako neke uzročno-posljedične veze nisu znanstveno utemeljene." To načelo je temelj za Europski zakon o okolišu i igra sve važniju ulogu u razvoju politike zaštite okoliša. Također se rabi u donošenju odluka vezanih za okoliš u Kanadi i nekoliko europskih zemalja, posebno Danskoj, Švedskoj i Njemačkoj. Načelo utvrđivanja rizika rabi se u postupku donošenja odluka vezanih za okoliš i u regulativi lijekova i ostalih proizvoda široke potrošnje u Sjedinjenim Američkim Državama. Načelo utvrđivanja rizika upotpunjuje skup podataka o riziku, između ostalog od kemikalija koje se proizvode u velikim količinama i općenito analiza koje se temelje na procjeni rizika. Načelo ne isključuje potrebu za znanošću ili znanstveno temeljene procjene rizika. Javnost je potaknuta na sudjelovanje u procjenjivanju i donošenju odluka. Načelo utvrđivanja rizika potiče, a u nekim slučajevima i zahtijeva transparentnost postupka procjene rizika od kemikalija opasnih za okoliš i zdravlje ljudi. Nastavlja se rasprava treba li načelo obuhvatiti direktivu "polluter pays" i postaviti odgovornost za provedbu procjene rizika u industriji. Najbolji elementi mjera opreza zahtijevaju dobru znanost i potiču znanstvenu zajednicu da unapređuje metode za procjenu rizika
THEORY OF DEFECTS IN CONDUCTING POLYMERS .2. APPLICATION TO POLYACETYLENE
We exploit the approach of a previous paper, based on self-consistent quantum-chemical molecular dynamics, to investigate the energetics and dynamics of excitations in conducting polymers. The predictions include the formation energies of solitons and polarons, the phenomenon of doping by alkali atoms, luminescence quenching in cis-polyacetylene, the soliton mobility in trans-polyacetylene and the non-existence of breathers in cis-polyacetylene
What Explains the Incidence of the Use of a Common Sediment Control on Lots with Houses Under Construction?
To analyze compliance with one aspect of the regulation of stormwater discharge, we estimate a random-utility model of the probability that a builder uses a silt fence to control sediments on a lot with a house under construction in an urbanizing county of South Carolina. The probability increases if the builder is responsible to the subdivision’s developer or if a homeowners association exists. The probability also increases as the cost to install a silt fence decreases or the number of houses under construction per built house in a subdivision increases. The results can help county officials target inspection to improve compliance.compliance with regulation, erosion and sediment control, filter fabric, management of stormwater runoff, random-utility model, silt fence, storm water pollution prevention plan, Agribusiness, Community/Rural/Urban Development, Demand and Price Analysis, Environmental Economics and Policy, Industrial Organization, Land Economics/Use, Q01, Q24, Q53, Q58,
Status of sonic boom methodology and understanding
In January 1988, approximately 60 representatives of industry, academia, government, and the military gathered at NASA-Langley for a 2 day workshop on the state-of-the-art of sonic boom physics, methodology, and understanding. The purpose of the workshop was to assess the sonic boom area, to determine areas where additional sonic boom research is needed, and to establish some strategies and priorities in this sonic boom research. Attendees included many internationally recognized sonic boom experts who had been very active in the Supersonic Transport (SST) and Supersonic Cruise Aircraft Research Programs of the 60's and 70's. Summaries of the assessed state-of-the-art and the research needs in theory, minimization, atmospheric effects during propagation, and human response are given
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Crystallographic Analysis and Mimicking of Estradiol Binding: Interpretation and Speculation
Substantiating harm reduction and supporting tobacco regulatory science
A framework for the assessment of novel next-generation tobacco and nicotine products with the potential to reduce health risks compared with cigarettes should integrate scientific studies incorpor..
Do ethnic differences in cord blood leptin levels differ by birthweight category? Findings from the Born in Bradford cohort study.
BACKGROUND: There is evidence that South Asian individuals have higher fat mass for a given weight than Europeans. One study reported that the greater fatness for a given birthweight may increase with increasing birth weight, suggesting that any attempt to increase mean birth weight in South Asians would markedly increase their fatness.
OBJECTIVE: Our objective was to examine whether differences in cord leptin values between White British and Pakistani infants vary by birth weight category.
METHOD: We examined the difference in cord leptin levels between 659 White British and 823 Pakistani infants recruited to the Born in Bradford cohort study, by clinical categories and thirds of the birth weight distribution.
RESULTS: Pakistani infants had a lower mean birthweight but higher cord leptin levels than White British infants [ratio of geometric mean(RGM) of cord leptin adjusted for birth weight = 1.36 (95% CI 1.26,1.46)]. Birthweight was positively associated with cord leptin levels in both groups, with no evidence that the regression lines in the two groups diverged from each other with increasing birthweight.The relative ethnic difference in cord leptin was similar in low (<2500 g), normal and high (≥4000 g) birthweight infants(P-value for interaction = 0.91). It was also similar across thirds of the birthweight distribution [RGM (95% CI) in lowest, mid and highest thirds were 1.37 (1.20, 1.57), 1.36 (1.20, 1.54) and 1.31 (1.16, 1.52), respectively, P-interaction = 0.51].
CONCLUSIONS: We found marked differences in cord leptin levels between Pakistani and White British infants but no evidence that this difference increases with increasing birthweight
Morphological Enumeration of Resting Spores in Sporosori of the Plant Pathogen Spongospora subterranean
Plasmodiophorid sporosori (aggregations of resting spores) reach their most complex form in Spongospora subterranea f. sp. subterranea, the biotrophic plant pathogen which causes the economically important disease powdery scab of potato (Solanum tuberosum). Resting spores are the perennation life cycle stage of plasmodiophorids, allowing them to survive for long periods and infect subsequent host generations. Light microscopy was used to measure resting spores and sporosori of Sp. subterranea, and enumerate resting spores in individual sporosori. Mean resting spore diameters differed for two sporosorus collections, being 4.0 μm (from New Zealand) and 4.3 μm (from Switzerland). Counts of resting spores in 4 μm thick serial sections of sporosori from one collection gave a mean of 667 (range 155 to 1,526) resting spores per sporosorus. Number of resting spores per sporosorus was closely related to sporosorus volume, and could be accurately estimated using the formula; number of resting spores = 0.0081 × sporosorus volume (assuming sporosori to be spheroids). Using this formula, mean numbers of resting spores in sporosori from 37 Sp. subterranea collections from field-grown potato tubers from 13 countries were determined to range from 199 to 713. Differences in numbers of resting spores between the collections were statistically significant (P < 0.05), and independent of country or host cultivar of origin, indicating that enumeration should be carried out for individual sporosorus collections to accurately quantify inoculum. Morphology, using scanning electron microscopy, also showed that between 2 and 51% (average 20%) of resting spores released zoospores after exposure to roots of host plants. The formula for resting spore enumeration validated in this study can be used to standardise Sp. subterranea resting spore inoculum for plant pathology studies, and possibly to assist determination of soil inoculum potential for disease risk evaluations
Religion's Role in Promoting Health and Reducing Risk Among American Youth
Although past research has long documented religion's salutary impact on adult health-related behaviors and outcomes, relatively little research has examined the relationship between religion and adolescent health. This study uses large, nationally representative samples of high school seniors to examine the relationship between religion and behavioral predictors of adolescent morbidity and mortality. Relative to their peers, religious youth are less likely to engage in behaviors that compromise their health (e.g., carrying weapons, getting into fights, drinking and driving) and are more likely to behave in ways that enhance their health (e.g., proper nutrition, exercise, and rest). Multivariate analyses suggest that these relationships persist even after controlling for demographic factors, and trend analyses reveal that they have existed over time. Particularly important is the finding that religious seniors have been relatively unaffected by past and recent increases in marijuana use.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66995/2/10.1177_109019819802500604.pd
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