303 research outputs found

    Survey of whole air data from the second airborne Biomass Burning and Lightning Experiment using principal component analysis

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    Hydrocarbon and halocarbon measurements collected during the second airborne Biomass Burning and Lightning Experiment (BIBLE-B) were subjected to a principal component analysis (PCA), to test the capability for identifying intercorrelated compounds within a large whole air data set. The BIBLE expeditions have sought to quantify and understand the products of burning, electrical discharge, and general atmospheric chemical processes during flights arrayed along the western edge of the Pacific. Principal component analysis was found to offer a compact method for identifying the major modes of composition encountered in the regional whole air data set. Transecting the continental monsoon, urban and industrial tracers (e.g., combustion byproducts, chlorinated methanes and ethanes, xylenes, and longer chain alkanes) dominated the observed variability. Pentane enhancements reflected vehicular emissions. In general, ethyl and propyl nitrate groupings indicated oxidation under nitrogen oxide (NOx) rich conditions and hence city or lightning influences. Over the tropical ocean, methyl nitrate grouped with brominated compounds and sometimes with dimethyl sulfide and methyl iodide. Biomass burning signatures were observed during flights over the Australian continent. Strong indications of wetland anaerobics (methane) or liquefied petroleum gas leakage (propane) were conspicuous by their absence. When all flights were considered together, sources attributable to human activity emerged as the most important. We suggest that factor reductions in general and PCA in particular may soon play a vital role in the analysis of regional whole air data sets, as a complement to more familiar methods

    Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 314)

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    This bibliography lists 139 reports, articles, and other documents introduced into the NASA scientific and technical information system in August, 1988

    Morphological variation of the diatom species Gomphonema parvulum KĂĽtz. under nutrient and shading treatment

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    Diatoms (Bacillariophyta) are unicellular microalgae inhabiting nearly all aquatic environments on Earth. Some taxa are endemic to certain regions, whereas some are widely spread or even cosmopolitan. Diatoms’ species diversity and habitat selection support their use as bioindicators, and traditional water quality indices are based on species composition and index species. However, trait-based indices have gained interest in recent years and researchers believe that traits could potentially act as a useful tool in environmental assessment. Traits refers to the morphological, physiological and phenological properties of species, and they are closely linked to the species’ capacity to grow and reproduce in certain circumstances. Morphological variation in diatoms varies significantly between taxa and species. The possibilities of a diatom to adapt into changing habitat is a result of its capacity to alter its morphological properties. Urban and agricultural land use affect water resources negatively, and climate change acts as a reinforcing factor creating complex and mixed effects on aquatic environments. Global warming is and will proceed to be strongest near the poles and its unique and harsh habitats. Climate change by anthropogenic activities and environmental pollution has affected and will affect microbial communities and primary producers everywhere. Diatoms have a central role in global productivity and biogeochemical cycle, and changes in microbial cell size could have severe implications for food webs and energy transition of energy in the trophic system. The aim of this thesis was to monitor the morphological properties, including the size, shape and striae density, of G. parvulum and its link to different combinations two stressors: nutrient solution (PO4 and NO3) and limited light availability. Shading treatment had a clear effect on average cell width, but average cell length did not correlate with shading. Nutrient treatment did not alter the cell length but had some effect on striae density. However, it was concluded that striae count or head shape are not most suitable for indicator purposes, as they are affected by cell size. In conclusion, no clear variation patterns according to the nutrient or shading treatment were detected, but result suggest that the increased availability of light could alter the size of G. parvulum. Results could be blurred by the small sample size or the presence of cryptic or semi-cryptic species

    Utility of remote sensing data in retrieval of water quality consituents concentrations in coastal water of New Jersey

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    Three important optical properties used for monitoring coastal water quality are the concentrations of chlorophyll (CHL), color dissolved organic matter (CDOM) and total suspended materials (TSM). Ocean color remote sensing, a technique to collect color data by detection of upward radiance from a distance (Bukata et al.,1995), provides a synoptic view for determining these concentrations from upwelling radiances. In the open ocean (Case-I), it is not difficult to derive empirical algorithms relating the received radiances to surface concentrations of water quality parameters. In coastal waters (Case-Il), there are serious unresolved problems in extracting chlorophyll concentration because of high concentration of suspended particles (Gordon and Morel, 1983). There are three basic approaches to estimate optical water quality parameters from remotely sensed spectral data based on the definitions given by Morel & Gordon (1980): (1) an empirical method, in which statistical relationships between the upward radiance at the sea surface and the quantity of interest are taken into account; (2) a semiempirical method, in which the spectral characteristics of the parameters of interest are known and some modeling of the physics is introduced; and (3) an analytical method, in which radiative transfer models are used to extract the inherent optical properties (lOPs) and a suite of analysis methods can be used to optimally retrieve the water constituents from the remotely sensed upwelling radiance or irradiance reflectance signal. The focus of this research is the modification and application of analytical and statistical algorithms to characterize the physically based surface spectral reflectance for the waters of the Hudson/Raritan Estuary and to retrieve the water constituent concentrations from the NASA Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and LIght Detection And Ranging (LIDAR) signals. The approaches used here are based on the unique capabilities of AVIRIS and LIDAR data which can potentially provide a better understanding of how sunlight interacts with estuarine/inland water, especially when complemented with in situ measurements for analysis of water quality parameters and eutrophication processes. The results of analysis in forms of thematic maps are then input into geographic information system (GIS) of the study site for use by water resource managers and planners for better monitoring and management of water quality condition

    Understanding building and urban environment interactions: An integrated framework for building occupancy modelling

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    Improving building energy efficiency requires accurate modelling and a comprehensive understanding of how occupants use building space. This thesis focuses on modelling building occupancy to enhance the predictive accuracy of occupancy patterns and gain a better understanding of the causal reasons for occupancy behaviour. A conceptual framework is proposed to relax the restriction of isolated building analysis, which accounts for interactions between buildings, its occupants, and other urban systems, such as the effects of transport incidents on occupancy and circulation in buildings. This thesis also presents a counterpart mapping of the framework that elaborates the links between modelling of transport and building systems. To operationalise the proposed framework, a novel modelling approach which has not been used in the current context, called the hazard-based model, is applied to model occupancy from a single building up to a district area. The proposed framework is further adapted to integrate more readily with transport models, to ensure that arrivals and departures to and from the building are consistent with the situation of the surrounding transport systems. The proposed framework and occupancy models are calibrated and validated using Wi-Fi data and other variables, such as transport and weather parameters, harvested from the South Kensington campus of Imperial College London. In addition to calibrating the occupancy model, integrating a travel simulator produces synthetic arrivals into or around the campus, which are further distributed over campus buildings via an adapted technique and feed the occupancy simulations. The model estimation results reveal the causal reasons for or exogenous effects on individual occupancy states. The validation results confirm the ability of the proposed models to predict building occupancy accurately both on average and day by day across the future dataset. Finally, evaluating occupancy simulations for various hypothetical scenarios provides valuable suggestions for efficient building design and facility operation.Open Acces

    Aerospace medicine and biology: A continuing bibliography with indexes (supplement 317)

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    This bibliography lists 182 reports, articles and other documents introduced into the NASA scientific and technical information system in November, 1988

    2022 GREAT Day Program

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    SUNY Geneseo’s Sixteenth Annual GREAT Day.https://knightscholar.geneseo.edu/program-2007/1016/thumbnail.jp

    Diet and dietary biomarkers during pregnancy and lactation in relation to offspring allergy development

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    Allergy causes a large burden on society and reduces the quality of life for the individual. The increased allergy incidence over the last decades cannot be explained by genetics. Research has indicated that diet, which is a modifiable factor, might influence the risk of developing allergy. Traditional dietary assessment methods are, however, prone to large measurement errors. Objective biomarkers may be complementary but have typically not been applied in cohorts with pregnant women and in the early life context.The objective of this thesis was to investigate if the diet during pregnancy and lactation is related to offspring allergy development (i.e., atopic eczema, food allergy, and asthma) diagnosed by an allergologist at twelve months of age. The thesis is based on data from the birth cohort Nutritional impact on Immunological maturation during Childhood in relation to the Environment (NICE). Dietary data were collected using a repeated web-based semi-quantitative food frequency questionnaire sent out in gestational week 34, one month postpartum, and four months postpartum. Dietary intakes were quantified based on pictures of portion sizes and reported intake frequency. Maternal and infant blood, urine, and breast milk samples were collected, and nutrients, trace elements, and metabolomics-based food intake biomarkers were related to the self-reported food intake and to allergy diagnosis.The results show that maternal intake of cow’s milk products and saturated fat during lactation was associated with a lower incidence of offspring allergy. Higher proportions of n-6 polyunsaturated fatty acids in umbilical cord plasma phospholipids correlated to a higher incidence of atopic eczema during thefirst year of life. In addition, food intake during pregnancy was associated with maternal characteristics, primarily age and educational level. Food intake biomarkers known from a general (i.e., non-pregnant or lactating) population seemed useful also during lactation, whilst dietary biomarkers during pregnancy warrant further investigation.In summary, the findings indicate that the most crucial period of time in terms of allergy prevention may be the first months postpartum, rather than during pregnancy. Hence, changing maternal diet during lactation may be a useful strategy for allergy prevention in the offspring

    International Students\u27 Psychological and Sociocultural Adaptation in the United States

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    International students constitute an important cohort in the United States (U.S.) colleges and universities. In order for the U.S. colleges and universities to better accommodate the significant number of international students and to recruit them in the future, it is critical to identify factors that influence these students’ acculturation and adjustment processes and provide professionals with guidelines for creating culturally appropriate services and programs for them. Therefore the current study examined international students’ adaptation to the U.S. in relation to their acculturation levels, coping processes, and intent to stay in the U.S. after their graduation. Center for Epidemiologic Studies - Depression scale was used as a measure of psychological adaptation. In addition, Sociocultural Adaptation Scale, Acculturation Index, and Ways of Coping Questionnaire, were used to measure sociocultural adaptation, acculturation dimensions, and coping processes, respectively. A total of 204 F1 visa holding international students participated in the current study. This project was a cross-sectional, exploratory study that measured depression and sociocultural adaptation among international students. Cronbach’s alpha for each instrument was calculated to determine the internal reliability for the current sample. Pearson product moment correlational analyses were performed to examine the relations between interval variables. Analysis of variance was utilized to examine gender differences in coping processes. Multiple regression analyses were conducted in order to explore the predictors of international students’ psychological and sociocultural adaptations. Results showed that in females identification with the host culture was associated with lower levels of depression, and Escape-Avoidance was associated with higher levels of depression. Identification with the host culture and Escape-Avoidance were predictors of sociocultural adaptation for both genders. Specifically, students who identified more strongly with the American culture were less likely to experience difficulty functioning in the U.S. In addition, these students were more likely to report higher levels of English proficiency, higher likelihood of staying in the U.S. after graduation, and lower levels of depression. The study identified important gender differences with regards to acculturation dimensions and coping processes. Implications and suggestions for future research were discussed
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