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Results 301 - 350 of 2246
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Lacy Fred - - 2011
Experimental evidence has made it clear that the size of an object can have an effect on its properties. The electrical resistivity of a thin film will become larger as the thickness of that film decreases in size. Furthermore, the electrical resistivity will also increase as the temperature increases. To ...
Alessandrelli Maria - - 2011
This paper aims at describing some relevant aspects related to the classification, labelling and packaging of nanomaterials. Concerns have been raised about potential adverse effects to humans or the environment as result of impacts of nanomaterials. The new Regulation (EC) no. 1272/2008 on classification, labelling and packaging of substances and ...
de Ceglia Francesco Paolo - - 2011
This article reconstructs the 19th century history of events regarding a few female wax anatomical models made in Florence. More or less faithful copies of those housed in Florence's Museum of Physics and Natural History, these models were destined for display in temporary exhibitions. In their travels through Europe and ...
Wu Chang-fu - - 2011
In the Seattle Air Toxics Monitoring Pilot Program, we measured 15 hazardous air pollutants (HAPs) at 6 sites for more than a year between 2000 and 2002. Spatial-temporal variations were evaluated with random-effects models and principal component analyses. The potential health risks were further estimated based on the monitored data, ...
Faul Franz - - 2011
In F. Faul and V. Ekroll (2002), we proposed a filter model of perceptual transparency that describes typical color changes caused by optical filters and accurately predicts perceived transparency. Here, we provide a more elaborate analysis of this model: (A) We address the question of how the model parameters can ...
Fischer Paul H - - 2011
Daily variations in the levels of air pollution are well known to be associated with daily variations in mortality counts. Given the large number of time-series studies, there is little need for simple replication of these results in additional locations. However, additional analyses of time-series data might be useful in ...
Khan S - - 2011
Stormwater retention ponds are one of the principal methods to treat stormwater runoff. Analysis of residence time distribution (RTD) curves can be used to evaluate the capability of these ponds for sediment removal. Deflector islands have been suggested as a means of improving the performance of retention ponds, due to ...
Monaco Cristián J - - 2011
The ongoing and future effects of global climate change on natural and human-managed ecosystems have led to a renewed interest in the concept of ecological thresholds or tipping points. While generalizations such as poleward range shifts serve as a useful heuristic framework to understand the overall ecological impacts of climate ...
Hyeon Changbong - - 2011
The distances over which biological molecules and their complexes can function range from a few nanometres, in the case of folded structures, to millimetres, for example, during chromosome organization. Describing phenomena that cover such diverse length, and also time, scales requires models that capture the underlying physics for the particular ...
Kim Samuel - - 2011
We propose a new methodology to model high-level descriptions of physical activities using multimodal sensor signals (ambulatory electrocardiogram (ECG) and accelerometer signals) obtained by a wearable wireless sensor network. We introduce a two-step strategy where the first step estimates likelihood scores over the low-level descriptions of physical activities such as ...
Thatte Gautam - - 2011
The optimal allocation of samples for physical activity detection in a wireless body area network for health-monitoring is considered. The number of biometric samples collected at the mobile device fusion center, from both device-internal and external Bluetooth heterogeneous sensors, is optimized to minimize the transmission power for a fixed number ...
Xia Ying - - 2011
Background. Physical activity classification is an objective approach to assess levels of physical activity, and indicates an individual's degree of functional ability. It is significant for a number of the disciplines, such as behavioural sciences, physiotherapy, etc. Accelerometry is found to be a practical and low cost method for activity ...
Soares Marta C - - 2011
In humans, physical stimulation, such as massage therapy, reduces stress and has demonstrable health benefits. Grooming in primates may have similar effects but it remains unclear whether the positive effects are due to physical contact or to its social value. Here we show that physical stimulation reduces stress in a ...
Campbell Ian H - - 2011
Ubiquitous and unobtrusive in-home monitoring has the potential to detect physical and mental decline earlier and with higher precision than current clinical methods. However, given that this field is in its infancy, the specific metrics through which these changes are detected are not well defined. The work presented here offers ...
Lee Paul H - - 2011
The International Physical Activity Questionnaire-Short Form (IPAQ-SF) has been recommended as a cost-effective method to assess physical activity. Several studies validating the IPAQ-SF have been conducted with differing results, but no systematic review of these studies has been reported. The keywords "IPAQ", "validation", and "validity" were searched in PubMed and ...
Huff David D - - 2011
The green sturgeon (Acipenser medirostris) is a highly migratory, oceanic, anadromous species with a complex life history that makes it vulnerable to species-wide threats in both freshwater and at sea. Green sturgeon population declines have preceded legal protection and curtailment of activities in marine environments deemed to increase its extinction ...
McCormack Gavin R - - 2011
Empirical evidence suggests that an association between the built environment and physical activity exists. This evidence is mostly derived from cross-sectional studies that do not account for other causal explanations such as neighborhood self-selection. Experimental and quasi-experimental designs can be used to isolate the effect of the built environment on ...
Cook Daniel L - - 2011
As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In ...
Krauss Jeffrey - - 2011
Short telomere length (TL) is an independent predictor of mortality in patients with coronary heart disease (CHD). However, the relationship between physical fitness and TL has not been explored in these patients. In a cross sectional study of 944 outpatients with stable CHD, we performed exercise treadmill testing, assessed self-reported ...
Kuffel Erin E - - 2011
Objective measurement of physical activity remains an important challenge. For wearable monitors such as accelerometer-based physical activity monitors, more accurate methods are needed to convert activity counts into energy expenditure (EE). The purpose of this study was to examine the accuracy of the refined Crouter 2-Regression Model (C2RM) for estimating ...
Saunders Travis J - - 2011
While we concur with the objectives of the recent International Journal of Behavioural Nutrition and Physical Activity paper published by Jago and colleagues titled "Physical activity and sedentary behaviour typologies of 10-11 year olds", we feel that the results as currently presented do not support their conclusions. Though the authors ...
Mannini Andrea - - 2011
Accelerometers are a popular choice as body-motion sensors: the reason is partly in their capability of extracting information that is useful for automatically inferring the physical activity in which the human subject is involved, beside their role in feeding biomechanical parameters estimators. Automatic classification of human physical activities is highly ...
Swinkels Raymond A H M - - 2011
In many countries, the need for physical therapists to use standardised measures has been recognised and is recommended in clinical practice guidelines. Research has shown a lack of clinimetric knowledge and clinical application of measurement instruments in daily practice may hamper implementation of these guidelines. The aims of our study ...
Christian Hayley E - - 2011
Understanding the relationship between urban design and physical activity is a high priority. Different representations of land use diversity may impact the association between neighbourhood design and specific walking behaviours. This study examined different entropy based computations of land use mix (LUM) used in the development of walkability indices (WIs) ...
Flanders W Dana - - 2011
A difficult issue in observational studies is assessment of whether important confounders are omitted or misspecified. In this study, we present a method for assessing whether residual confounding is present. Our method depends on availability of an indicator with 2 key characteristics: first, it is conditionally independent (given measured exposures ...
Sherar Lauren B LB College of Kinesiology, University of Saskatchewan, Saskatoon, SK, Canada. - - 2011
Over the past decade, accelerometers have increased in popularity as an objective measure of physical activity in free-living individuals. Evidence suggests that objective measures, rather than subjective tools such as questionnaires, are more likely to detect associations between physical activity and health in children. To date, a number of studies ...
Morales Terrés Isabel M - - 2010
This paper describes a novel methodology for evaluating the extent to which petrol stations affect their surroundings. The method is based on the fact that the ratio of the concentrations of aliphatic and aromatic hydrocarbon pollutants in the air of the petrol stations and their surroundings (basically determined by vapor ...
Kriech Anthony J - - 2010
Field studies were conducted at paving and roofing sites to compare the German Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA) Fourier transform infrared spectroscopy method 6305 with the National Institute for Occupational Science and Health (NIOSH) benzene soluble fraction method 5042 plus total organic ...
Lee Duncan - - 2010
Summary In studies that estimate the short-term effects of air pollution on health, daily measurements of pollution concentrations are often available from a number of monitoring locations within the study area. However, the health data are typically only available in the form of daily counts for the entire area, meaning ...
Persily A - - 2010
A set of 209 dwellings that represent 80% of U.S. housing stock is used to generate frequency distributions of residential infiltration rates. The set of homes is based on an analysis of the 1997 U.S. Department of Energy's Residential Energy Consumption Survey, which documents numerous housing characteristics including type, floor ...
Sana Aria - - 2011
The diagnosis of chronic gastrointestinal ischemia (CGI) remains a clinical challenge. We aimed to assess the diagnostic value of clinical features, visualization of the gastrointestinal arteries, and evaluation of mucosal perfusion in patients clinically suspected of CGI. A total of 186 patients referred for suspicion of CGI were prospectively included ...
Grant Daniel T - - 2010
Flight capability for micro air vehicles is rapidly maturing throughout the aviation community; however, mission capability has not yet matured at the same pace. Maintaining trim during a descent or in the presence of crosswinds remains challenging for fixed-wing aircraft but yet is routinely performed by birds. This paper presents ...
Salway Ruth - - 2010
This paper describes the use of Bayesian latent variable models in the context of studies investigating the short-term effects of air pollution on health. Traditional Poisson or quasi-likelihood regression models used in this area assume that consecutive outcomes are independent (although the latter allows for overdispersion), which in many studies ...
Donovan Sally Maree - - 2011
The aim of this research was to predict the effect that the biodegradable municipal waste (BMW) diversion targets in the European Union landfill directive (99/31/EC) would have on landfill gas emissions. This is important for continued mitigation of these emissions. Work was undertaken in three stages using the GasSim model ...
Hammond Davyda - - 2011
Communities are concerned over pollution levels and seek methods to systematically identify and prioritize the environmental stressors in their communities. Geographic information system (GIS) maps of environmental information can be useful tools for communities in their assessment of environmental-pollution-related risks. Databases and mapping tools that supply community-level estimates of ambient ...
Carlton Annmarie G - - 2010
Numerous scientific upgrades to the representation of secondary organic aerosol (SOA) are incorporated into the Community Multiscale Air Quality (CMAQ) modeling system. Additions include several recently identified SOA precursors: benzene, isoprene, and sesquiterpenes; and pathways: in-cloud oxidation of glyoxal and methylglyoxal, particle-phase oligomerization, and acid enhancement of isoprene SOA. NO(x)-dependent ...
Spatari Sabrina - - 2010
Renewable and low carbon fuel standards being developed at federal and state levels require an estimation of the life cycle carbon intensity (LCCI) of candidate fuels that can substitute for gasoline, such as second generation bioethanol. Estimating the LCCI of such fuels with a high degree of confidence requires the ...
Breen Michael S - - 2010
A critical aspect of air pollution exposure models is the estimation of the air exchange rate (AER) of individual homes, where people spend most of their time. The AER, which is the airflow into and out of a building, is a primary mechanism for entry of outdoor air pollutants and ...
Laner David - - 2011
Municipal solid waste landfills need to be managed after closure. This so-called aftercare comprises the treatment and monitoring of residual emissions as well as the maintenance and control of landfill elements. The measures can be terminated when a landfill does not pose a threat to the environment any more. Consequently, ...
Viana Mar - - 2010
African dust (AD) contributions to particulate matter (PM) levels may be reported by Member States to the European Commission during justification of exceedances of the daily limit value (DLV). However, the detection and subsequent quantification of the AD contribution to PM levels is complex, and only two measurement-based methods are ...
Lundstedt-Enkel Katrin - - 2010
Baltic Sea herring (Clupea harengus) is a pelagic, zoo-planktivorous fish and young (2-5 years old) individuals of this species are sampled annually in the Swedish marine monitoring program. This study determined concentrations of organochlorines (OCs) and brominated flame retardants (BFRs) in dorsal muscle from herring (n = 60) of varying ...
Ishizawa Yumiko - - 2011
General anesthetics are administered to approximately 50 million patients each year in the United States. Anesthetic vapors and gases are also widely used in dentists' offices, veterinary clinics, and laboratories for animal research. All the volatile anesthetics that are currently used are halogenated compounds destructive to the ozone layer. These ...
Venkatesh Aranya - - 2011
The climate change impacts of U.S. petroleum-based fuels consumption have contributed to the development of legislation supporting the introduction of low carbon alternatives, such as biofuels. However, the potential greenhouse gas (GHG) emissions reductions estimated for these policies using life cycle assessment methods are predominantly based on deterministic approaches that ...
Jacques David R - - 2010
A simplified building airflow model is presented that can be used to predict the spread of a contaminant agent from a chemical or biological attack. If the dominant means of agent transport throughout the building is an air-handling system operating at steady-state, a linear time-invariant (LTI) model can be constructed ...
Plevin Richard J - - 2010
The life cycle greenhouse gas (GHG) emissions induced by increased biofuel consumption are highly uncertain: individual estimates vary from each other and each has a wide intrinsic error band. Using a reduced-form model, we estimated that the bounding range for emissions from indirect land-use change (ILUC) from US corn ethanol ...
Chakraborty Paromita - - 2010
India has extensive production and usage of organochlorine pesticides (OCPs) for agriculture and vector control. Despite this, few data are available on the levels and distribution of OCPs in the urban atmosphere of India. Passive and active air sampling was therefore conducted between Dec 2006 and March 2007 in 7 ...
Schuster Jasmin K - - 2010
Long-term air monitoring data sets are needed for persistent organic pollutants (POPs), to assess the effectiveness of source abatement measures and the factors controlling ambient levels. The Toxic Organic Micro-Pollutants (TOMPS) program in the United Kingdom started in 1991, generating a data set for polychlorinated biphenyls (PCBs). The history and ...
Belland Kxis M - - 2010
In 1998, the Navy's center of excellence for advanced air wing combat operations, namely the Naval Strike and Air Warfare Center (NSAWC), had a spike in Class A flight mishaps. The spike triggered an intense review of prior mishaps and current mishap-reduction practices using the Human Factors Analysis and Classification ...
Fernandez Linda - - 2011
We apply a fixed-effects model to examine the impact of trade and environmental policies on air quality at ports along the U.S.-Mexico border. We control for other factors influencing air quality, such as air quality of cities near the border, volume of traffic flows and congestion. Results show the air ...
Grinn-GofroĊ„ Agnieszka - - 2011
Fungal spores are an important component of bioaerosol and also considered to act as indicator of the level of atmospheric bio-pollution. Therefore, better understanding of these phenomena demands a detailed survey of airborne particles. The objective of this study was to examine the dependence of two the most important allergenic ...
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