Search results for "position"
showing 10 items of 6771 documents
COARSEMAP: synthesis of observations and models for coarse-mode aerosols
2017
Coarse mode aerosols influence Earth's climate and biogeochemistry by interacting with long-wave radiation, promoting ice nucleation, and contributing important elements to biogeochemical cycles during deposition. Yet coarse mode aerosols have received less emphasis in the scientific literature. Here we present first efforts to globally synthesize available mass concentration, compositionand optical depth data and modeling for the coarse mode aerosols (<10 μm) in a new project called "COARSEMAP" (http://www.geo.cornell.edu/eas/PeoplePlaces/Faculty/mahowald/COARSEMAP/). We seek more collaborators who have observational data, especially including elemental or composition data, and/or who a…
Water-Insoluble Organics Dominate Brown Carbon in Wintertime Urban Aerosol of China: Chemical Characteristics and Optical Properties.
2020
The chromophores responsible for light absorption in atmospheric brown carbon (BrC) are not well characterized, which hinders our understanding of BrC chemistry, the links with optical properties, and accurate model representations of BrC to global climate and atmospheric oxidative capacity. In this study, the light absorption properties and chromophore composition of three BrC fractions of different polarities were characterized for urban aerosol collected in Xi'an and Beijing in winter 2013-2014. These three BrC fractions show large differences in light absorption and chromophore composition, but the chromophores responsible for light absorption are similar in Xi'an and Beijing. Water-ins…
Jerarquización y preferencia de valores en los estudiantes de secundaria = Hierarchial structuring and preference of values in the students of second…
2014
This article describes a study of the values and variables that influence hierarchical structuring in secondary school students. The main objectives are to determine which are the preferred values and to compare in what manner gender and age are related to the values of adolescents. The study is conducted with a sample (n=114) of male and female secondary school students, between 14 and 18 years old. The results show that the two variables (gender and age) are related to the subject’s values. Girls prefer final values, more abstract and internalized values; opposite to the instrumental, more egocentric and material values, preferred by boys. Regarding age influence, as they grow older, adol…
Development of Methods for the Evaluation of Olive Oil Oxidation
2012
In this work, the chemical changes produced in an EVOO sample, both in the presence and absence of its phenolic fraction during an accelerated ageing treatment have been studied. The changes produced in phenolic compound concentrations, jointly with the changes observed in free acidity, peroxide value, UV absorbance, fatty acid composition, OSI and T content, were monitored. In addition, transformation of phenolic compounds during the accelerated ageing treatment in EVOO samples with phenolic fraction was also studied.
SW—Soil and Water
2002
Abstract Recent research has directed attention to the size distribution of eroded material because of its influence on deposition mechanics and in carrying capacity of pollutant materials. At first, in this paper the relationship between aggregate breakdown mechanism and erosion processes is briefly reviewed. Then the link between the clay enrichment ratio and the sediment delivery ratio at morphological unit scale is investigated. For 129 soil samples well distributed over the Sicilian Sparacia basin, the values for the experimental clay enrichment ratio calculated by the measured ultimate grain-size distributions are compared with the theoretical clay enrichment ratio values obtained by …
Dynamic Mechanical Behavior Analysis of Flax/Jute Fiber-Reinforced Composites under Salt-Fog Spray Environment
2020
Over the last decades, natural fiber-reinforced polymer composites (NFRPs) gained great attention in several engineering fields thanks to the reduction of the environmental impact and the end-of-life cost disposal. Unfortunately, the use of NFRPs is limited, mainly due to their weak resistance against humid environments. Since limited literature is available about the evolution of the dynamic mechanical response of NFRPs under aggressive environments, this paper aims to investigate the damping properties of flax, jute and flax/jute epoxy composites exposed to salt-fog up to 60 days. Furthermore, sodium bicarbonate fiber treatment was performed to improve the composites&rsquo
Biological clocks and physical functioning in monozygotic female twins
2018
Background Biomarkers of biological aging – DNA methylation age (DNAm age) and leukocyte telomere length (LTL)– correlate strongly with chronological age across the life course. It is, however, unclear how these measures of cellular wear and tear are associated with muscle strength and functional capacity, which are known to decline with older age and are associated with mortality. We investigated if DNAm age and LTL were associated with body composition and physical functioning by examining 48 monozygotic twin sisters. Methods White blood cell DNAm age (predicted years) was calculated from Illumina 450 k BeadChip methylation data using an online calculator. DNAm age acceleration was define…
Major histocompatibility complex and sporadic Alzheimer's disease: a critical reappraisal
2003
Epidemiological data suggest that some genetic determinants of Alzheimer's disease (AD) might reside in those polymorphisms for the immune system genes that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, MHC polymorphisms have been the focus of a large number of AD association studies. Class Ia, Ib (hemochromatosis gene (HFE)), class II and class III (complement, tumour necrosis factor and heat shock proteins) alleles have been studied. Nearly every positive result has been followed by several studies that have failed to replicate it or that have contradicted it. Several factors, including methodological biases, might explain these dis…
Associations of socio-economic position and disability among older women in Britain and Jyväskylä, Finland
2005
The aim was to compare the pattern of associations in measures of socio-economic position and disability among British and Finnish older women. In Britain data from the British Women's Heart and Health Study was used. Women from 23 towns took part in a nurse-assessed medical examination and postal questionnaire (n = 4286). In Finland, data from the Evergreen study was used. Eight hundred and four women from the city of Jyväskylä were interviewed at home. Socio-economic position was measured according to social class in childhood, education, use of a car, home ownership and previous occupation. Disability measures included questions on difficulties in washing/dressing and climbing stairs. Lo…
Meta-analysis of genome-wide association studies from the CHARGE consortium identifies common variants associated with carotid intima media thickness…
2011
Carotid intima media thickness (cIMT) and plaque determined by ultrasonography are established measures of subclinical atherosclerosis that each predicts future cardiovascular disease events. We conducted a meta-analysis of genome-wide association data in 31,211 participants of European ancestry from nine large studies in the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. We then sought additional evidence to support our findings among 11,273 individuals using data from seven additional studies. In the combined meta-analysis, we identified three genomic regions associated with common carotid intima media thickness and two different regions a…