1,424 research outputs found
2000 Families: identifying the research potential of an origins - of migration study
Despite extensive recent advances in the empirical and theoretical study of migration, certain critical areas in the analysis of European migration remain relatively underdeveloped both theoretically and empirically. Specifically, we lack studies that both incorporate an origin comparison and trace processes of intergenerational transmission across migrants over multiple generations and incorporating family migration trajectories. This paper outlines the development, data and design of such a study, the 2000 Families study, framed within a theoretical perspective of ?dissimilation? from origins and over generations. We term the study an origins-of-migration study, in that it captures the country of origin, the family origins and potentially the originating causes of migration processes and outcomes. The resulting data comprised nearly 2,000 migrant and non-migrant Turkish families with members across three or more generations, covering. 50,000 individuals. We reflect on the potential of this study for migration research
Development of a Coherent Bistatic Vegetation Model for Signal of Opportunity Applications at VHF UHF-Bands
A coherent bistatic vegetation scattering model, based on a Monte Carlo simulation, is being developed to simulate polarimetric bi-static reflectometry at VHF/UHF-bands (240-270 MHz). The model is aimed to assess the value of geostationary satellite signals of opportunity to enable estimation of the Earth's biomass and root-zone soil moisture. An expression for bistatic scattering from a vegetation canopy is derived for the practical case of a ground-based/low altitude platforms with passive receivers overlooking vegetation. Using analytical wave theory in conjunction with distorted Born approximation (DBA), the transmit and receive antennas effects (i.e., polarization, orientation, height, etc.) are explicitly accounted for. Both the coherency nature of the model (joint phase and amplitude information) and the explicit account of system parameters (antenna, altitude, polarization, etc) enable one to perform various beamforming techniques to evaluate realistic deployment configurations. In this paper, several test scenarios will be presented and the results will be evaluated for feasibility for future biomass and root-zone soil moisture application using geostationary communication satellite signals of opportunity at low frequencies
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Dehydration of potato slices following brief dipping in osmotic solutions: effect of conditions and understanding the mechanism of water loss
A novel variant of osmotic dehydration, named here as post-dipping dehydration – where a material is dipped in a salt or sugar solution for a very short time followed by simple exposure to ambient conditions was explored with the aim of lowering water content of potato slices but at the same time not gain a high level of sugar/salt. The rate of water loss, which was rapid initially, was found to approach equilibrium. This paper also explored whether the water loss process could subsequently be kick started once again, by employing a multi-stage process, where each stage consisted of osmotic solution dipping followed by ambient holding of the potato slices that had reached equilibrium in the earlier stage. Water loss values comparable to conventional osmotic dehydration could be achieved thus, but with significantly lower overall solid gain (less than 50%) – which can potentially yield a significantly healthy product option
Large-Area (over 50 cm × 50 cm) Freestanding Films of Colloidal InP/ZnS Quantum Dots
Cataloged from PDF version of article.We propose and demonstrate the fabrication of flexible, freestanding films of InP/ZnS quantum dots (QDs) using fatty acid ligands across very large areas (greater than 50 cm x 50 cm), which have been developed for remote phosphor applications in solid-state lighting. Embedded in a poly(methyl methacrylate) matrix, although the formation of stand alone films using other QDs commonly capped with trioctylphosphine oxide (TOPO) and oleic acid is not efficient, employing myristic acid as ligand in the synthesis of these QDs, which imparts a strongly hydrophobic character to the thin film, enables film formation and ease of removal even on surprisingly large areas, thereby avoiding the need for ligand exchange. When pumped by a blue LED, these Cd-free QD films allow for high color rendering, warm white light generation with a color rendering index of 89.30 and a correlated color temperature of 2298 K. In the composite film, the temperature-dependent emission kinetics and energy transfer dynamics among different-sized InP/ZnS QDs are investigated and a model is proposed. High levels of energy transfer efficiency (up to 80%) and strong donor lifetime modification (from 18 to 4 ns) are achieved. The suppression of the nonradiative channels is observed when the hybrid film is cooled to cryogenic temperatures. The lifetime changes of the donor and acceptor InP/ZnS QDs in the film as a result of the energy transfer are explained well by our theoretical model based on the exciton-exciton interactions among the dots and are in excellent agreement with the experimental results. The understanding of these excitonic interactions is essential to facilitate improvements in the fabrication of photometrically high quality nanophosphors. The ability to make such large-area, flexible, freestanding Cd-free QD films pave the way for environmentally friendly phosphor applications including flexible, surface-emitting light engines
Alcohol drinking in one's thirties and forties is associated with body mass index in men, but not in women: A longitudinal analysis of the 1970 British Cohort Study
Our objective was to investigate longitudinal associations between alcohol drinking and body mass index (BMI). Alcohol drinking (exposure), BMI (outcome), smoking habit, occupation, longstanding illness, and leisure time physical activity (potential confounders) were assessed at ages 30, 34, 42, and 46 in the 1970 British Birth Cohort Study. Multilevel models were used to cope with the problem of correlated observations. There were 15,708 observations in 5931 men and 14,077 observations in 5656 women. Drinking was associated with BMI in men. According to the regression coefficients, BMI was expected to increase by 0.36 (95% confidence interval: 0.11, 0.60) kg/m2 per year in men who drank once a week and by 0.40 (0.14, 0.15) kg/m2 per year in men who drank most days. In ten years, BMI was expected to increase by 5.4 kg/m2 in men who drank and by 2.9 kg/m2 in men who drank and were physically active. Drinking was not associated with BMI in women. Rather, BMI was expected to increase by 0.25 (0.07, 0.43) kg/m2 per year in women who were former smokers. In ten years, BMI was expected to increase by 4.3 kg/m2 in women who were former smokers and by 0.8 kg/m2 in women who were former smokers and who were physically active. Associations between drinking and BMI were similar after further adjustment for problematic drinking and diet. These longitudinal data suggest that drinking is associated with BMI in men and that drinking is not associated with BMI in women independent of other lifestyle risk factors
A Large Hadron Electron Collider at CERN
This document provides a brief overview of the recently published report on
the design of the Large Hadron Electron Collider (LHeC), which comprises its
physics programme, accelerator physics, technology and main detector concepts.
The LHeC exploits and develops challenging, though principally existing,
accelerator and detector technologies. This summary is complemented by brief
illustrations of some of the highlights of the physics programme, which relies
on a vastly extended kinematic range, luminosity and unprecedented precision in
deep inelastic scattering. Illustrations are provided regarding high precision
QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed
to run synchronously with the LHC in the twenties and to achieve an integrated
luminosity of O(100) fb. It will become the cleanest high resolution
microscope of mankind and will substantially extend as well as complement the
investigation of the physics of the TeV energy scale, which has been enabled by
the LHC
Systematic study of trace radioactive impurities in candidate construction materials for EXO-200
The Enriched Xenon Observatory (EXO) will search for double beta decays of
136Xe. We report the results of a systematic study of trace concentrations of
radioactive impurities in a wide range of raw materials and finished parts
considered for use in the construction of EXO-200, the first stage of the EXO
experimental program. Analysis techniques employed, and described here, include
direct gamma counting, alpha counting, neutron activation analysis, and
high-sensitivity mass spectrometry.Comment: 32 pages, 6 figures. Expanded introduction, added missing table
entry. Accepted for publication in Nucl. Instrum. Meth.
Application of poly(2-hydroxyethyl methacrylate) hydrogel disks for the immobilization of three different microalgal species
BACKGROUND: Algal growth on solid surfaces confers the advantage of combining the algal harvesting and bioprocessing steps at a single stage, in addition to the easier handling of the immobilized cells that occupy a reduced amount of space. The current work employed the application of macroporous poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel disks as a water-insoluble, non-toxic and recyclable immobilization matrix for different microalgal strains (Nannochloropsis sp., Dunaliella salina, and Botryococcus braunii) that offer value-added products for various commercial applications.
RESULTS: The study demonstrated the effect of variations in the surface characteristics of the algal strains and hydrogel surfaces on the immobilization efficiencies. Gelatin was further used to modify PHEMA hydrogels to achieve higher bioaffinity and surface hydrophilicity. The results showed that highly salt-tolerant microalgal cells (Dunaliella salina, Nannochloropsis sp.) had significantly higher tendencies to attach on the gelatin-modified PHEMA hydrogel compared with the freshwater B. braunii colonies; embedded within an extracellular matrix mainly made of hydrophobic components, which displayed better attachment to the unmodified PHEMA hydrogels.
CONCLUSION: The proposed PHEMA hydrogels are easily-manufactured and highly durable materials with the hydrogel disks still retaining their integrity after several years when in contact with a liquid. PHEMA disks also have the benefits of having adjustable porosities by changing the composition of the polymerization mixture, and modifiable surface properties by simply binding various synthetic or natural molecules on their surfaces, which can bring several new opportunities for harvesting various microalgal cells with different surface morphologies and chemical compositions
Joint association of alcohol consumption and adiposity with alcohol- and obesity-related cancer in a population sample of 399,575 UK adults.
Obesity and alcohol consumption are both important modifiable risk factors for cancer. We examined the joint association of adiposity and alcohol consumption with alcohol- and obesity-related cancer incidence. This prospective cohort study included cancer-free UK Biobank participants aged 40-69 years. Alcohol consumption was categorised based on current UK guidelines into four groups. We defined three markers of adiposity: body fat percentage (BF %), waist circumference and BMI and categorised each into three groups. We derived a joint alcohol consumption and adiposity marker variable with twelve mutually exclusive categories. Among 399 575 participants, 17 617 developed alcohol-related cancer and 20 214 developed obesity-related cancer over an average follow-up of 11·8 (SD 0·9) years. We found relatively weak evidence of independent associations of alcohol consumption with cancer outcomes. However, the joint association analyses showed that across all adiposity markers, above guideline drinkers who were in the top two adiposity groups had elevated cancer incidence risk (e.g. HR for alcohol-related cancer was 1·53 (95 % CI (1·24, 1·90)) for within guideline drinkers and 1·61 (95 % CI (1·30, 2·00)) for above guideline drinkers among participants who were in the top tertile BF %. Regardless of alcohol consumption status, the risk of obesity-related cancer increased with higher adiposity in a dose-response manner within alcohol consumption categories. Our study provides guidance for public health priorities aimed at lowering population cancer risk via two key modifiable risk factors
Alcohol intake and mortality risk of COVID-19, pneumonia, and other infectious diseases: An analysis of 437191 UK biobank participants
This study aims to investigate the association between alcohol consumption and COVID-19, infectious diseases, and pneumonia mortality. This is a prospective analysis of 437,191 UK Biobank participants (age 56.3 years, 54% female). The main exposure was self-reported alcohol consumption. In addition to never and previous drinkers, we applied quartiles-based and UK guidelines-based criteria to divide current drinkers by weekly consumption into four groups. Outcomes included COVID-19, infectious diseases, and pneumonia mortality, obtained from the national death registries until May 2020. After an 11-year follow-up, compared to never drinkers, previous drinkers had higher mortality risks of infectious diseases and pneumonia (adjusted HR: 1.29 [95% CI 1.06–1.57] and 1.35 [1.07–1.70], respectively), but not COVID-19. There was a curvilinear association of alcohol consumption with infectious diseases and pneumonia mortality. Drinking within-guidelines (<14 UK units/wk) and amounts up to double the recommendation (14 to < 28 UK units/wk) was associated with the lowest mortality risks of infectious diseases (0.70 [0.59–0.83] and 0.70 [0.59–0.83], respectively) and pneumonia (0.71 [0.58–0.87] and 0.72 [0.58–0.88], respectively). Alcohol consumption was associated with lower risks of COVID-19 mortality (e.g., drinking within-guidelines: 0.53 [0.33–0.86]). Drinkers reporting multiples of the recommended alcohol drinking amounts did not have higher mortality risks of COVID-19 and other infectious diseases than never drinkers. Despite the well-established unfavorable effects on general health, we found no deleterious associations between alcohol consumption and the risk of infectious diseases, including COVID-19. Future research with other study designs is needed to confirm the causality
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