790 research outputs found
Neighbors' income, public goods, and wellâbeing
How does neighbors' income affect individual wellâbeing? Our analysis is based on rich U.S. local data from the Behavioral Risk Factor Surveillance System, which contains information on where respondents live and their selfâreported wellâbeing. We find that the effect of neighbors' income on individuals' selfâreported wellâbeing varies with the size of the neighborhood included. In smaller areas such as ZIP codes, we find a positive relationship between median income and individuals' life satisfaction, whereas it is the opposite at the county, MSA, and state levels. We provide evidence that local public goods and local area characteristics such as unemployment, criminality, and poverty rates drive the association between satisfaction and neighbors' income at the ZIP code level. The neighbors' income effects are mainly concentrated among poorer individuals and are as large as one quarter of the effect of own income on selfâreported wellâbeing
Exploring the Value of Understanding Society for Neighbourhood Effects Analyses
Related data set âUnderstanding Society: Waves 1-6, 2009-2015â with DOI http://dx.doi.org/10.5255/UKDA-SN-6614-7 in repository âUK Data Serviceâ.Understanding Society is a large representative household panel study for the UK. The study follows the same 40,000 households over time, beginning in 2009 and providing a detailed picture of how peopleâs lives are changing. One of the many innovative features of Understanding Society is that a great deal of information about neighbourhoods can be used alongside the individual and household-level information collected in the study, making it a useful study for neighbourhood effects analyses. In this paper we explore four Understanding Society data products, based on four different types of rural-urban neighbourhood classifications, to throw light on how much heterogeneity in neighbourhood contexts is captured in the first waves of Understanding Society, including change in neighbourhood contexts
Hotter Is Better and Broader: Thermal Sensitivity of Fitness in a Population of Bacteriophages
Hotter is better is a hypothesis of thermal adaptation that posits that the rate-depressing effects of low temperature on biochemical reactions cannot be overcome by physiological plasticity or genetic adaptation. If so, then genotypes or populations adapted to warmer temperatures will have higher maximum growth rates than those adapted to low temperatures. Here we test hotter is better by measuring thermal reaction norms for intrinsic rate of population growth among an intraspecific collection of bacteriophages recently isolated from nature. Consistent with hotter is better, we find that phage genotypes with higher optimal temperatures have higher maximum growth rates. Unexpectedly, we also found that hotter is broader, meaning that the phages with the highest optimal temperatures also have the greatest temperature ranges. We found that the temperature sensitivity of fitness for phages is similar to that for insects
Linear Compressor Suction Valve Optimization
Design of hermetic compressors for household refrigeration follows a common sequence that considers an initial concept, normally based on existing families. Those are then upgraded with new features, aiming improvements in efficiency, sound quality or even cost reduction. Common compressors have a cylinder head that carries discharge and suction valve. In a new and compact designs for linear compressor suction valve is placed on the top of the piston, requiring new shapes in order to make it possible to satisfy, gas flow, fatigue and dynamics requirements. This article aims to present the use of optimization procedure used to develop the suction valve design for a linear compressor, the results obtained with the optimization process, and final results in compressor, in terms of performance and noise
Erroneous Arrhenius: Modified Arrhenius Model Best Explains the Temperature Dependence of Ectotherm Fitness
The initial rise of fitness that occurs with increasing temperature is attributed to Arrhenius kinetics, in which rates of reaction increase exponentially with increasing temperature. Models based on Arrhenius typically assume single rate-limiting reaction(s) over some physiological temperature range for which all the rate-limiting enzymes are in 100% active conformation. We test this assumption using datasets for microbes that have measurements of fitness (intrinsic rate of population growth) at many temperatures and over a broad temperature range, and for diverse ectotherms that have measurements at fewer temperatures. When measurements are available at many temperatures, strictly Arrhenius kinetics is rejected over the physiological temperature range. However, over a narrower temperature range, we cannot reject strictly Arrhenius kinetics. The temperature range also affects estimates of the temperature dependence of fitness. These results indicate that Arrhenius kinetics only apply over a narrow range of temperatures for ectotherms, complicating attempts to identify general patterns of temperature dependence
eROSITA studies of the Carina Nebula
© 2024 The Author(s). Published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Context. During the first four all-sky surveys eRASS:4, which was carried out from December 2019 to 2021, the extended Roentgen Survey with an Imaging Telescope Array (eROSITA) on board the Spektrum-Roentgen-Gamma (Spektr-RG, SRG) observed the Galactic H II region, the Carina nebula. Aims. We analysed the eRASS:4 data to study the distribution and spectral properties of the hot interstellar plasma and the bright stellar sources in the Carina nebula. Methods. The spectral extraction regions of the diffuse emission were defined based on the X-ray spectral morphology and multi-wavelength data. The spectra were fit with a combination of thermal and non-thermal emission models. The X-ray bright point sources in the Carina nebula are the colliding wind binary η Car, several O stars, and WolfâRayet (WR) stars. We extracted the spectra of the brightest stellar sources, which can be well fit with a multi-component thermal plasma model. Results. The spectra of the diffuse emission in the brighter parts of the Carina nebula are well reproduced by two thermal models, a lower-temperature component (~0.2 keV) and a higher-temperature component (0.6â0.8 keV). An additional non-thermal component dominates the emission above ~1 keV in the Central region around η Car and the other massive stars. Significant orbital variation in the X-ray flux was measured for η Car, WR 22, and WR 25. η Car requires an additional time-variable thermal component in the spectral model, which is associated with the wind-wind collision zone. Conclusions. Properties such as temperature, pressure, and luminosity of the X-ray emitting plasma in the Carina nebula derived from the eROSITA data are consistent with theoretical calculations of emission from superbubbles. This confirms that the X-ray emission is caused by the hot plasma inside the Carina nebula that has been shocked-heated by the stellar winds of the massive stars, in particular, of η Car.Peer reviewe
The Genetic Basis of Thermal Reaction Norm Evolution in Lab and Natural Phage Populations
Two major goals of laboratory evolution experiments are to integrate from genotype to phenotype to fitness, and to understand the genetic basis of adaptation in natural populations. Here we demonstrate that both goals are possible by re-examining the outcome of a previous laboratory evolution experiment in which the bacteriophage G4 was adapted to high temperatures. We quantified the evolutionary changes in the thermal reaction normsâthe curves that describe the effect of temperature on the growth rate of the phagesâand decomposed the changes into modes of biological interest. Our analysis indicated that changes in optimal temperature accounted for almost half of the evolutionary changes in thermal reaction norm shape, and made the largest contribution toward adaptation at high temperatures. Genome sequencing allowed us to associate reaction norm shape changes with particular nucleotide mutations, and several of the identified mutations were found to be polymorphic in natural populations. Growth rate measures of natural phage that differed at a site that contributed substantially to adaptation in the lab indicated that this mutation also underlies thermal reaction norm shape variation in nature. In combination, our results suggest that laboratory evolution experiments may successfully predict the genetic bases of evolutionary responses to temperature in nature. The implications of this work for viral evolution arise from the fact that shifts in the thermal optimum are characterized by tradeoffs in performance between high and low temperatures. Optimum shifts, if characteristic of viral adaptation to novel temperatures, would ensure the success of vaccine development strategies that adapt viruses to low temperatures in an attempt to reduce virulence at higher (body) temperatures
eROSITA studies of the Carina Nebula
During the first four all-sky surveys eRASS:4 carried out from December 2019
to 2021, the extended Roentgen Survey with an Imaging Telescope Array (eROSITA)
on board Spektrum-Roentgen-Gamma (Spektr-RG, SRG) observed the Galactic HII
region Carina nebula. We analysed the eRASS:4 data to study the distribution
and the spectral properties of the hot interstellar plasma and the bright
stellar sources in the Carina nebula. Spectral extraction regions of the
diffuse emission were defined based on X-ray spectral morphology and
multi-wavelength data. The spectra were fit with a combination of thermal and
non-thermal emission models. X-ray bright point sources in the Carina nebula
are the colliding wind binary Car, several O stars, and Wolf-Rayet (WR)
stars. We extracted the spectrum of the brightest stellar sources, which can be
well fit with a multi-component thermal plasma model. The spectra of the
diffuse emission in the brighter parts of the Carina nebula is well reproduced
by two thermal models, a lower-temperature component (0.2 keV) and a
higher-temperature component (0.6 - 0.8 keV). An additional non-thermal
component dominates the emission above 1 keV in the central region around
Car and the other massive stars. Significant orbital variation of the
X-ray flux was measured for Car, WR22 and WR25. Car requires an
additional time-variable thermal component in the spectral model, which is
associated to the wind-wind-collision zone. Properties like temperature,
pressure, and luminosity of the X-ray emitting plasma in the Carina nebula
derived from the eROSITA data are consistent with theoretical calculations of
emission from superbubbles. It confirms that the X-ray emission is caused by
the hot plasma inside the Carina nebula which has been shocked-heated by the
stellar winds of the massive stars, in particular, of Car.Comment: Accepted for publication in Astronomy & Astrophysic
Linking PIAAC Data to Individual Administrative Data: Insights from a German Pilot Project
Linking survey data to administrative data offers researchers many opportunities. In particular, it enables them to enrich survey data with additional information without increasing the burden on respondents. German PIAAC data on individual skills, for example, can be combined with administrative data on individual employment histories. However, as the linkage of survey data with administrative data records requires the consent of respondents, there may be bias in the linked dataset if only a subsample of respondents - for example, high-educated individuals - give their consent. The present chapter provides an overview of the pilot project about linking the German PIAAC data with individual administrative data. In a first step, we illustrate characteristics of the linkable datasets and describe the linkage process and its methodological challenges. In a second step, we provide an illustrative example of the use of the linked data and investigate how the skills assessed in PIAAC are associated with the linkage decision
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