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Showing papers by "Oklahoma State University–Stillwater published in 2014"


Journal ArticleDOI
TL;DR: Global rates of change suggest that only 16 countries will achieve the MDG 5 target by 2015, with evidence of continued acceleration in the MMR, and MMR was highest in the oldest age groups in both 1990 and 2013.

1,383 citations


Journal ArticleDOI
TL;DR: The Global Burden of Disease 2013 study provides a consistent and comprehensive approach to disease estimation for between 1990 and 2013, and an opportunity to assess whether accelerated progress has occured since the Millennium Declaration.

875 citations


Journal ArticleDOI
TL;DR: By combining the freedom of both the structural design and the orientation of split ring resonator antennas, this work demonstrates terahertz metasurfaces that are capable of controlling both the phase and amplitude profiles over a very broad bandwidth.
Abstract: By combining the freedom of both the structural design and the orientation of split ring resonator antennas, we demonstrate terahertz metasurfaces that are capable of controlling both the phase and amplitude profiles over a very broad bandwidth. As an example, we show that the phase-amplitude metasurfaces can be engineered to control the diffraction orders arbitrarily.

569 citations


Journal ArticleDOI
TL;DR: In this paper, a planar terahertz metamaterial was used for ultra-sensitive sensing in the fingerprint region of the tera-hertz regime, where the low-loss quadrupole and Fano resonances with extremely narrow linewidths were used to measure the minute spectral shift caused due to the smallest change in the refractive index of the surrounding media.
Abstract: High quality factor resonances are extremely promising for designing ultra-sensitive refractive index label-free sensors, since it allows intense interaction between electromagnetic waves and the analyte material. Metamaterial and plasmonic sensing have recently attracted a lot of attention due to subwavelength confinement of electromagnetic fields in the resonant structures. However, the excitation of high quality factor resonances in these systems has been a challenge. We excite an order of magnitude higher quality factor resonances in planar terahertz metamaterials that we exploit for ultrasensitive sensing. The low-loss quadrupole and Fano resonances with extremely narrow linewidths enable us to measure the minute spectral shift caused due to the smallest change in the refractive index of the surrounding media. We achieve sensitivity levels of 7.75 × 103 nm/refractive index unit (RIU) with quadrupole and 5.7 × 104 nm/RIU with the Fano resonances which could be further enhanced by using thinner substrates. These findings would facilitate the design of ultrasensitive real time chemical and biomolecular sensors in the fingerprint region of the terahertz regime.

565 citations


Journal ArticleDOI
S. Chatrchyan, Khachatryan1, Albert M. Sirunyan, Armen Tumasyan  +2384 moreInstitutions (207)
26 May 2014
TL;DR: In this paper, a description of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices is provided.
Abstract: A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tt events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p_T > 0.9GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p_T = 100GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p_T, and respectively, 10μm and 30μm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10–12μm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

559 citations


Journal ArticleDOI
TL;DR: It is argued that although recent progress has been impressive, the next decade will yield even more substantial insights not only into how domestication took place, but also when and where it did, and where and why it did not.
Abstract: It is difficult to overstate the cultural and biological impacts that the domestication of plants and animals has had on our species. Fundamental questions regarding where, when, and how many times domestication took place have been of primary interest within a wide range of academic disciplines. Within the last two decades, the advent of new archaeological and genetic techniques has revolutionized our understanding of the pattern and process of domestication and agricultural origins that led to our modern way of life. In the spring of 2011, 25 scholars with a central interest in domestication representing the fields of genetics, archaeobotany, zooarchaeology, geoarchaeology, and archaeology met at the National Evolutionary Synthesis Center to discuss recent domestication research progress and identify challenges for the future. In this introduction to the resulting Special Feature, we present the state of the art in the field by discussing what is known about the spatial and temporal patterns of domestication, and controversies surrounding the speed, intentionality, and evolutionary aspects of the domestication process. We then highlight three key challenges for future research. We conclude by arguing that although recent progress has been impressive, the next decade will yield even more substantial insights not only into how domestication took place, but also when and where it did, and where and why it did not.

555 citations


Journal ArticleDOI
TL;DR: Despite consistency in average values of SOC and root biomass between data and data from rangelands worldwide, broad ranges in root biomass and SOC in data suggest these variables are affected by other site-specific factors.
Abstract: Soils contain much of Earth’s terrestrial organic carbon but are sensitive to land-use. Rangelands are important to carbon dynamics and are among ecosystems most widely impacted by land-use. While common practices like grazing, fire, and tillage affect soil properties directly related to soil carbon dynamics, their magnitude and direction of change vary among ecosystems and with intensity of disturbance. We describe variability in soil organic carbon (SOC) and root biomass—sampled from 0–170 cm and 0–100 cm, respectively—in terms of soil properties, land-use history, current management, and plant community composition using linear regression and multivariate ordination. Despite consistency in average values of SOC and root biomass between our data and data from rangelands worldwide, broad ranges in root biomass and SOC in our data suggest these variables are affected by other site-specific factors. Pastures with a recent history of severe grazing had reduced root biomass and greater bulk density. Ordination suggests greater exotic species richness is associated with lower root biomass but the relationship was not apparent when an invasive species of management concern was specifically tested. We discuss how unexplained variability in belowground properties can complicate measurement and prediction of ecosystem processes such as carbon sequestration.

498 citations


Journal ArticleDOI
Georges Aad1, Alexander Kupco2, Peter Davison2, Samuel Webb3  +2918 moreInstitutions (81)
TL;DR: In this paper, the ATLAS detector at the Large Hadron Collider is used to search for high-mass resonances decaying to dielectron or dimuon final states.
Abstract: The ATLAS detector at the Large Hadron Collider is used to search for high-mass resonances decaying to dielectron or dimuon final states. Results are presented from an analysis of proton-proton (pp) collisions at a center-of-mass energy of 8 TeV corresponding to an integrated luminosity of 20.3 fb(-1) in the dimuon channel. A narrow resonance with Standard Model Z couplings to fermions is excluded at 95% confidence level for masses less than 2.79 TeV in the dielectron channel, 2.53 TeV in the dimuon channel, and 2.90 TeV in the two channels combined. Limits on other model interpretations are also presented, including a grand-unification model based on the E-6 gauge group, Z* bosons, minimal Z' models, a spin-2 graviton excitation from Randall-Sundrum models, quantum black holes, and a minimal walking technicolor model with a composite Higgs boson.

364 citations


Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2871 moreInstitutions (167)
TL;DR: In this article, the authors presented the electron and photon energy calibration achieved with the ATLAS detector using about 25 fb(-1) of LHC proton-proton collision data taken at center-of-mass energies of root s = 7 and 8 TeV.
Abstract: This paper presents the electron and photon energy calibration achieved with the ATLAS detector using about 25 fb(-1) of LHC proton-proton collision data taken at centre-of-mass energies of root s = 7 and 8 TeV. The reconstruction of electron and photon energies is optimised using multivariate algorithms. The response of the calorimeter layers is equalised in data and simulation, and the longitudinal profile of the electromagnetic showers is exploited to estimate the passive material in front of the calorimeter and reoptimise the detector simulation. After all corrections, the Z resonance is used to set the absolute energy scale. For electrons from Z decays, the achieved calibration is typically accurate to 0.05% in most of the detector acceptance, rising to 0.2% in regions with large amounts of passive material. The remaining inaccuracy is less than 0.2-1% for electrons with a transverse energy of 10 GeV, and is on average 0.3% for photons. The detector resolution is determined with a relative inaccuracy of less than 10% for electrons and photons up to 60 GeV transverse energy, rising to 40% for transverse energies above 500 GeV.

361 citations


Journal ArticleDOI
TL;DR: It is argued that cattle migration, movement and trading followed by admixture have been important forces in shaping modern bovine genomic variation.
Abstract: The domestication and development of cattle has considerably impacted human societies, but the histories of cattle breeds and populations have been poorly understood especially for African, Asian, and American breeds. Using genotypes from 43,043 autosomal single nucleotide polymorphism markers scored in 1,543 animals, we evaluate the population structure of 134 domesticated bovid breeds. Regardless of the analytical method or sample subset, the three major groups of Asian indicine, Eurasian taurine, and African taurine were consistently observed. Patterns of geographic dispersal resulting from co-migration with humans and exportation are recognizable in phylogenetic networks. All analytical methods reveal patterns of hybridization which occurred after divergence. Using 19 breeds, we map the cline of indicine introgression into Africa. We infer that African taurine possess a large portion of wild African auroch ancestry, causing their divergence from Eurasian taurine. We detect exportation patterns in Asia and identify a cline of Eurasian taurine/indicine hybridization in Asia. We also identify the influence of species other than Bos taurus taurus and B. t. indicus in the formation of Asian breeds. We detect the pronounced influence of Shorthorn cattle in the formation of European breeds. Iberian and Italian cattle possess introgression from African taurine. American Criollo cattle originate from Iberia, and not directly from Africa with African ancestry inherited via Iberian ancestors. Indicine introgression into American cattle occurred in the Americas, and not Europe. We argue that cattle migration, movement and trading followed by admixture have been important forces in shaping modern bovine genomic variation.

343 citations


Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2911 moreInstitutions (209)
TL;DR: In this paper, a measurement of the Z/gamma* boson transverse momentum spectrum using ATLAS proton-proton collision data at a centre-of-mass energy of root s = 7TeV at the LHC is described.
Abstract: This paper describes a measurement of the Z/gamma* boson transverse momentum spectrum using ATLAS proton-proton collision data at a centre-of-mass energy of root s = 7TeV at the LHC. The measurement is performed in the Z/gamma* -> e(+)e(-) and Z/gamma* -> mu(+)mu(-) channels, using data corresponding to an integrated luminosity of 4.7 fb(-1). Normalized differential cross sections as a function of the Z/gamma* boson transverse momentum are measured for transverse momenta up to 800 GeV. The measurement is performed inclusively for Z/gamma* rapidities up to 2.4, as well as in three rapidity bins. The channel results are combined, compared to perturbative and resummed QCD calculations and used to constrain the parton shower parameters of Monte Carlo generators.

Journal ArticleDOI
TL;DR: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently produce genome-scale data sets for phylogenomics.
Abstract: Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca) were used to design enrichment probes for 3385 exons from 768 genes (>1.6 Mbp) followed by Illumina sequencing of enriched libraries. Hyb-Seq of 12 individuals (10 Asclepias species and two related genera) resulted in at least partial assembly of 92.6% of exons and 99.7% of genes and an average assembly length >2 Mbp. Importantly, complete plastomes and nuclear ribosomal DNA cistrons were assembled using off-target reads. Phylogenomic analyses demonstrated signal conflict between genomes. Conclusions: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently...

Journal ArticleDOI
TL;DR: This paper examines the consistency of survey results across student samples, consumer panels, and online crowdsourcing markets (specifically Amazon's Mechanical Turk) both within the United States and outside and finds that U.S. OCM samples produced models that lead to similar statistical conclusions as both U. s. and non-U.s. participants.
Abstract: Online crowdsourcing markets (OCM) are becoming more popular as a source for data collection. In this paper, we examine the consistency of survey results across student samples, consumer panels, and online crowdsourcing markets (specifically Amazon's Mechanical Turk) both within the United States and outside. We conduct two studies examining the technology acceptance model (TAM) and the expectation-disconfirmation theory (EDT) to explore potential differences in demographics, psychometrics, structural model estimates, and measurement invariances. Our findings indicate that (1) U.S.-based OCM samples provide demographics much more similar to our student and consumer panel samples than the non-U.S.-based OCM samples; (2) both U.S. and non-U.S. OCM samples provide initial psychometric properties (reliability, convergent, and divergent validity) that are similar to those of both student and consumer panels; (3) non-U.S. OCM samples generally provide differences in scale means compared to those of our students, consumer panels, and U.S. OCM samples; and (4) one of the non-U.S. OCM samples refuted the highly replicated and validated TAM model in the relationship of perceived usefulness to behavioral intentions. Although our post hoc analyses isolated some cultural and demographic effects with regard to the non-U.S. samples in Study 1, they did not address the model differences found in Study 2. Specifically, the inclusion of non-U.S. OCM respondents led to statistically significant differences in parameter estimates, and hence to different statistical conclusions. Due to these unexplained differences that exist within the non-U.S. OCM samples, we caution that the inclusion of non-U.S. OCM participants may lead to different conclusions than studies with only U.S. OCM participants. We are unable to conclude whether this is due to of cultural differences, differences in the demographic profiles of non-U.S. OCM participants, or some unexplored factors within the models. Therefore, until further research is conducted to explore these differences in detail, we urge researchers utilizing OCMs with the intention to generalize to U.S. populations focus on U.S.-based participants and exercise caution in using non-U.S. participants. We further recommend that researchers should clearly describe their OCM usage and design (e.g., demographics, participant filters, etc.) procedures. Overall, we find that U.S. OCM samples produced models that lead to similar statistical conclusions as both U.S. students and U.S. consumer panels at a considerably reduced cost.

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2916 moreInstitutions (211)
TL;DR: In this article, a search for squarks and gluinos in final states containing high-p T jets, missing transverse momentum and no electrons or muons is presented.
Abstract: A search for squarks and gluinos in final states containing high-p T jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2012 by the ATLAS experiment in s√=8 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 20.3 fb−1. Results are interpreted in a variety of simplified and specific supersymmetry-breaking models assuming that R-parity is conserved and that the lightest neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 1330 GeV for a simplified model incorporating only a gluino and the lightest neutralino. For a simplified model involving the strong production of first- and second-generation squarks, squark masses below 850 GeV (440 GeV) are excluded for a massless lightest neutralino, assuming mass degenerate (single light-flavour) squarks. In mSUGRA/CMSSM models with tan β = 30, A 0 = −2m 0 and μ > 0, squarks and gluinos of equal mass are excluded for masses below 1700 GeV. Additional limits are set for non-universal Higgs mass models with gaugino mediation and for simplified models involving the pair production of gluinos, each decaying to a top squark and a top quark, with the top squark decaying to a charm quark and a neutralino. These limits extend the region of supersymmetric parameter space excluded by previous searches with the ATLAS detector.

Journal ArticleDOI
TL;DR: The experimental results for large-sized problems from a large set of randomly generated graphs as well as graphs of real-world problems with various characteristics show that the proposed MPQGA algorithm outperforms two non-evolutionary heuristics and a random search method in terms of schedule quality.

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2870 moreInstitutions (169)
TL;DR: The performance of the ATLAS muon reconstruction during the LHC run withpp collisions at s=7–8 TeV in 2011–2012 is presented, focusing mainly on data collected in 2012.
Abstract: This paper presents the performance of the ATLAS muon reconstruction during the LHC run with pp collisions at root s = 7-8 TeV in 2011-2012, focusing mainly on data collected in 2012. Measurements ...

Journal ArticleDOI
Georges Aad1, T. Abajyan2, Brad Abbott3, Jalal Abdallah4  +2885 moreInstitutions (169)
TL;DR: In this article, the electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton-proton collision data collected in 2011 at TeV and corresponding to an integrated luminosity of 4.7 fb.
Abstract: Many of the interesting physics processes to be measured at the LHC have a signature involving one or more isolated electrons. The electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton-proton collision data collected in 2011 at TeV and corresponding to an integrated luminosity of 4.7 fb. Tag-and-probe methods using events with leptonic decays of and bosons and mesons are employed to benchmark these performance parameters. The combination of all measurements results in identification efficiencies determined with an accuracy at the few per mil level for electron transverse energy greater than 30 GeV.

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2868 moreInstitutions (187)
TL;DR: In this paper, an improved measurement of the mass of the Higgs boson is derived from a combined fit to the reconstructed invariant mass spectra of the decay channels H -> gamma gamma and H -> ZZ* -> 4l.
Abstract: An improved measurement of the mass of the Higgs boson is derived from a combined fit to the reconstructed invariant mass spectra of the decay channels H -> gamma gamma and H -> ZZ* -> 4l. The analysis uses the pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at center-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of 25 fb(-1). The measured value of the Higgs boson mass is m(H) = 125.36 +/- 0.37(stat) +/- 0.18 (syst) GeV. This result is based on improved energy-scale calibrations for photons, electrons, and muons as well as other analysis improvements, and supersedes the previous result from ATLAS. Upper limits on the total width of the Higgs boson are derived from fits to the invariant mass spectra of the H -> gamma gamma and H -> ZZ* -> 4l decay channels.

Journal ArticleDOI
TL;DR: This work presents an orthogonal approach which proceeds via photochemically catalyzed isomerization of the thermodynamic E-alkene to the less stable Z-isomer which occurs via a photochemical pumping mechanism.
Abstract: Catalytic access to thermodynamically less stable Z-alkenes has recently received considerable attention. These approaches have relied upon kinetic control of the reaction to arrive at the thermodynamically less stable geometrical isomer. Herein, we present an orthogonal approach which proceeds via photochemically catalyzed isomerization of the thermodynamic E-alkene to the less stable Z-isomer which occurs via a photochemical pumping mechanism. We consider two potential mechanisms. Importantly, the reaction conditions are mild, tolerant, and operationally simple and will be easily implemented.

Journal ArticleDOI
TL;DR: A new fitness evaluation mechanism to continuously differentiate individuals into different degrees of optimality beyond the classification of the original Pareto dominance is introduced, and the concept of fuzzy logic is adopted to define a fuzzy Pare to domination relation.
Abstract: Evolutionary algorithms have been effectively used to solve multiobjective optimization problems with a small number of objectives, two or three in general. However, when problems with many objectives are encountered, nearly all algorithms perform poorly due to loss of selection pressure in fitness evaluation solely based upon the Pareto optimality principle. In this paper, we introduce a new fitness evaluation mechanism to continuously differentiate individuals into different degrees of optimality beyond the classification of the original Pareto dominance. The concept of fuzzy logic is adopted to define a fuzzy Pareto domination relation. As a case study, the fuzzy concept is incorporated into the designs of NSGA-II and SPEA2. Experimental results show that the proposed methods exhibit better performance in both convergence and diversity than the original ones for solving many-objective optimization problems.

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2916 moreInstitutions (196)
TL;DR: In this paper, a measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.4 GeV.
Abstract: A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, called the signal strength, is found to be mu = 1.17 +/- 0.27 at the value of the Higgs boson mass measured by ATLAS, m(H) = 125.4 GeV. The analysis is optimized to measure the signal strengths for individual Higgs boson production processes at this value of m(H). They are found to be mu(ggF) = 1.32 +/- 0.38, mu(VBF) = 0.8 +/- 0.7, mu(WH) = 1.0 +/- 1.6, mu(ZH) = 0.1(-0.1)(+3.7), and mu t (t) over barH = 1.6(-1.8)(+2.7), for Higgs boson production through gluon fusion, vector-boson fusion, and in association with a W or Z boson or a top-quark pair, respectively. Compared with the previously published ATLAS analysis, the results reported here also benefit from a new energy calibration procedure for photons and the subsequent reduction of the systematic uncertainty on the diphoton mass resolution. No significant deviations from the predictions of the Standard Model are found.

Journal ArticleDOI
TL;DR: The move towards understanding of anaerobic fungi using -omics based (genomic, transcriptomic and proteomic) approaches is starting to yield valuable insights into the unique cellular processes, evolutionary history, metabolic capabilities and adaptations that exist within the Neocallimastigomycota.

Journal ArticleDOI
TL;DR: This article focuses on the growing understanding of bacteria and archaea responsible for the degradation of hydrocarbons under aerobic conditions in moderate to high salinity conditions and reveals that degradation of oxygenated and non-oxygenated hydrocarbon degradation by halophilic and halotolerant microorganisms occur by pathways similar to those found in non-halophiles.
Abstract: Many hypersaline environments are often contaminated with petroleum compounds. Among these, oil and natural gas production sites all over the world and hundreds of kilometers of coastlines in the more arid regions of Gulf countries are of major concern due to the extent and magnitude of contamination. Because conventional microbiological processes do not function well at elevated salinities, bioremediation of hypersaline environments can only be accomplished using high salt-tolerant microorganisms capable of degrading petroleum compounds. In the last two decades, there have been many reports on the biodegradation of hydrocarbons in moderate to high salinity environments. Numerous microorganisms belonging to the domain Bacteria and Archaea have been isolated and their phylogeny and metabolic capacity to degrade a variety of aliphatic and aromatic hydrocarbons in varying salinities have been demonstrated. This article focuses on our growing understanding of bacteria and archaea responsible for the degradation of hydrocarbons under aerobic conditions in moderate to high salinity conditions. Even though organisms belonging to various genera have been shown to degrade hydrocarbons, members of the genera Halomonas Alcanivorax, Marinobacter, Haloferax, Haloarcula, and Halobacterium dominate the published literature. Despite rapid advances in understanding microbial taxa that degrade hydrocarbons under aerobic conditions, not much is known about organisms that carry out similar processes in anaerobic conditions. Also, information on molecular mechanisms and pathways of hydrocarbon degradation in high salinity is scarce and only recently there have been a few reports describing genes, enzymes and breakdown steps for some hydrocarbons. These limited studies have clearly revealed that degradation of oxygenated and non-oxygenated hydrocarbons by halophilic and halotolerant microorganisms occur by pathways similar to those found in non-halophiles.

Journal ArticleDOI
TL;DR: Job insecurity and work organization hazards play a role in creating and sustaining occupational health disparities and employment and workplace policies and programs have the potential to reduce these hazards, and to reduce disparities.
Abstract: This article appeared in a journal published by Wiley-Blackwell. Under Wiley's copyright, mandated authors are not permitted to make work available in an institutional repository.

Journal ArticleDOI
TL;DR: In this article, the authors examined the mediating role of perceived organizational support as explanations for employees' job satisfaction and performance and provided evidence explaining how and why these variables impact important workplace outcomes and extend existing theory by identifying appraisals of the organization as a mechanism explaining stressor-strain relationships.
Abstract: The literature on organizational change has increasingly recognized that characteristics of change recipients influence their reactions to workplace change. Yet little is known about the influence of employees’ adaptability and change-related uncertainty on their interpretation of organizational actions. We examined these antecedents and the mediating role of perceived organizational support as explanations for employees’ job satisfaction and performance. A survey was administered to material handling employees from two organizations. Employees completed measures of individual adaptability, uncertainty experienced regarding changes in the workplace, support received from the organization, and job satisfaction. Performance data were collected from the records of one organization. Results from both samples support the role of perceived organizational support as a mediator of the relationship between employees’ adaptability and perceptions of change-related uncertainty and employees’ satisfaction and performance. Change is a frequent occurrence in today’s workplace; thus, improving employee satisfaction and performance requires the consideration of change-related perceptions and individuals’ dispositions relevant to change. The present study offers insights regarding how organizations may help improve perceptions of organizational support by reducing perceived uncertainty as well as identifying employees who may need assistance to adapt to workplace changes. Despite practitioners’ expressed interest, there is scant research examining employees’ adaptability and change-related uncertainty. We provide the first evidence explaining how and why these variables impact important workplace outcomes and extend existing theory by identifying appraisals of the organization (and not the self) as a mechanism explaining stressor–strain relationships.

Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2870 moreInstitutions (169)
01 Nov 2014
TL;DR: In this paper, the performance of ATLAS muon reconstruction during the LHC run with pp collisions at root s = 7-8 TeV in 2011-2012, focusing mainly on data collected in 2012.
Abstract: This paper presents the performance of the ATLAS muon reconstruction during the LHC run with pp collisions at root s = 7-8 TeV in 2011-2012, focusing mainly on data collected in 2012. Measurements ...

Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2916 moreInstitutions (196)
01 Dec 2014
TL;DR: In this paper, a measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.4 GeV.
Abstract: A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, called the signal strength, is found to be mu = 1.17 +/- 0.27 at the value of the Higgs boson mass measured by ATLAS, m(H) = 125.4 GeV. The analysis is optimized to measure the signal strengths for individual Higgs boson production processes at this value of m(H). They are found to be mu(ggF) = 1.32 +/- 0.38, mu(VBF) = 0.8 +/- 0.7, mu(WH) = 1.0 +/- 1.6, mu(ZH) = 0.1(-0.1)(+3.7), and mu t (t) over barH = 1.6(-1.8)(+2.7), for Higgs boson production through gluon fusion, vector-boson fusion, and in association with a W or Z boson or a top-quark pair, respectively. Compared with the previously published ATLAS analysis, the results reported here also benefit from a new energy calibration procedure for photons and the subsequent reduction of the systematic uncertainty on the diphoton mass resolution. No significant deviations from the predictions of the Standard Model are found.

Journal ArticleDOI
TL;DR: Analysis of General Social Survey data from 1974 to 2012 finds that there has been significant partisan and ideological polarization on support for environmental spending since 1992-consistent with the expectations of party sorting theory.

Journal ArticleDOI
Georges Aad1, T. Abajyan2, Brad Abbott3, Jalal Abdallah4  +2913 moreInstitutions (200)
TL;DR: In this article, the authors search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in root s=8 TeV pp collisions with the ATLAS detector.
Abstract: Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in root s=8 TeV pp collisions with the ATLAS detector

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Jalal Abdallah3, S. Abdel Khalek4  +2881 moreInstitutions (168)
TL;DR: In this paper, two different analysis strategies based on monojetlike and c-tagged event selections are carried out to optimize the sensitivity for direct top-squark-pair production in the decay channel to a charm quark and the lightest neutralino.
Abstract: Results of a search for supersymmetry via direct production of third-generation squarks are reported, using 20.3 fb(-1) of proton-proton collision data at root s = 8 TeV recorded by the ATLAS experiment at the LHC in 2012. Two different analysis strategies based on monojetlike and c-tagged event selections are carried out to optimize the sensitivity for direct top squark-pair production in the decay channel to a charm quark and the lightest neutralino ((t) over tilde (1) -> c + (chi) over tilde (0)(1)) across the top squark-neutralino mass parameter space. No excess above the Standard Model background expectation is observed. The results are interpreted in the context of direct pair production of top squarks and presented in terms of exclusion limits in the (m((t) over tilde1), m((chi) over tilde 10)) parameter space. A top squark of mass up to about 240 GeV is excluded at 95% confidence level for arbitrary neutralino masses, within the kinematic boundaries. Top squark masses up to 270 GeV are excluded for a neutralino mass of 200 GeV. In a scenario where the top squark and the lightest neutralino are nearly degenerate in mass, top squark masses up to 260 GeV are excluded. The results from the monojetlike analysis are also interpreted in terms of compressed scenarios for top squark-pair production in the decay channel (t) over tilde (1) -> b + ff' + (chi) over tilde (0)(1) and sbottom pair production with (b) over tilde -> b + (chi) over tilde (0)(1), leading to a similar exclusion for nearly mass-degenerate third-generation squarks and the lightest neutralino. The results in this paper significantly extend previous results at colliders.