4,666 research outputs found
Energy savings measures in compressed air systems
Compressed air is one of the most widely used application energies in the industry, such as good transportability, safety, purity, cleanliness, storage capacity and ease of use. In many countries, compressed air systems account for approximately 10% of the industryâs total electricity consumption. Despite all its advantages, compressed air is expensive, only between 10% and 30% of the energy consumed reaches the point of final use. Energy is lost as heat, leaks, pressure drop, misuse, among others. Energy efficiency measures such as: reducing compressor pressure, lowering air inlet temperature, adequate storage capacity, recovering residual heat from the air compressor and reducing leakage, can produce energy savings between 20% and 60%, with an average return on investment lower than 2 years. This paper analyzes the main energy efficiency measures that can be applied in the CASs, the potential energy savings, implementation costs and return rate of each of them are being calculated giving a necessary tool for companies in their objectives to reduce greenhouse gas emissions and energy consumption
Psychometric properties and invariance of an English self-efficacy scale for university students in Peru
"Background: English is a global language used to communicate with members
of the international community. Self-efficacy in learning English is an important
factor that is influenced by perceived importance, interest, and beliefs about the
ability to successfully perform tasks in English.
Objective: The aim is to develop and validate a measurement instrument to
assess English self-efficacy.
Methods: A total of 453 students from different Peruvian universities participated,
with ages ranging from 18 to 60âyears (Mâ=â23; SDâ=â6.18). Statistical techniques
for latent variables were used and recommendations for educational and
psychological tests were followed in its construction. The sample was divided
into two groups to perform exploratory factor analysis (EFA) and confirmatory
factor analysis (CFA).
Results: The English Self-Efficacy Scale (ESS-P) is representative and relevant in
terms of its item content (Aikenâs Vâ>â0.70). Its internal structure is organized into
three first order factors and a second order factor that are consistent with the
theoretical proposal and was confirmed through CFA with excellent goodnessof-fit indices (Ď2
â=â1184.9, glâ=â626, CFIâ=â0.92, TLIâ=â0.92, RMSEAâ=â0.06 y SRMRâ=â0.04).
It also has adequate internal consistency in its three factors (Reading Îą/Ďâ=â0.96),
Oral Communication (Îą/Ďâ=â0.95), and Writing (Îą/Ďâ=â0.97) and the whole scale
(Îą/Ďâ=â0.98), is invariant with respect to sex, and has a conceptual relationship with
variables such as academic self-efficacy and exam anxiety.
Conclusion: The ESS-P is a measurement instrument with evidence of validity,
factorial invariance, and good reliability of its scores. Therefore, it can be used in
future studies in the academic contex
Multivariate analysis of 1.5 million people identifies genetic associations with traits related to self-regulation and addiction
Behaviors and disorders related to self-regulation, such as substance use, antisocial behavior and attention-deficit/hyperactivity disorder, are collectively referred to as externalizing and have shared genetic liability. We applied a multivariate approach that leverages genetic correlations among externalizing traits for genome-wide association analyses. By pooling data from ~1.5 million people, our approach is statistically more powerful than single-trait analyses and identifies more than 500 genetic loci. The loci were enriched for genes expressed in the brain and related to nervous system development. A polygenic score constructed from our results predicts a range of behavioral and medical outcomes that were not part of genome-wide analyses, including traits that until now lacked well-performing polygenic scores, such as opioid use disorder, suicide, HIV infections, criminal convictions and unemployment. Our findings are consistent with the idea that persistent difficulties in self-regulation can be conceptualized as a neurodevelopmental trait with complex and far-reaching social and health correlates
Metaproteomics characterization of the alphaproteobacteria microbiome in different developmental and feeding stages of the poultry red mite Dermanyssus gallinae (De Geer, 1778)
The poultry red mite (PRM), Dermanyssus gallinae (De Geer, 1778), is a worldwide distributed ectoparasite and considered a major pest affecting the laying hen industry in Europe. Based on available information in other ectoparasites, the mite microbiome might participate in several biological processes and the acquisition, maintenance and transmission of pathogens. However, little is known about the role of PRM as a mechanical carrier or a biological vector in the transmission of pathogenic bacteria. Herein, we used a metaproteomics approach to characterize the alphaproteobacteria in the microbiota of PRM, and variations in its profile with ectoparasite development (nymphs vs. adults) and feeding (unfed vs. fed). The results showed that the bacterial community associated with D. gallinae was mainly composed of environmental and commensal bacteria. Putative symbiotic bacteria of the genera Wolbachia, C. Tokpelaia and Sphingomonas were identified, together with potential pathogenic bacteria of the genera Inquilinus, Neorickettsia and Roseomonas. Significant differences in the composition of alphaproteobacterial microbiota were associated with mite development and feeding, suggesting that bacteria have functional implications in metabolic pathways associated with blood feeding. These results support the use of metaproteomics for the characterization of alphaproteobacteria associated with the D. gallinae microbiota that could provide relevant information for the understanding of mite-host interactions and the development of potential control interventions.El ĂĄcaro rojo de las aves de corral (PRM) , Dermanyssus gallinae (De Geer, 1778), es un ectoparĂĄsito distribuido en todo el mundo y considerado una plaga importante que afecta a la industria de las gallinas ponedoras en Europa. SegĂşn la informaciĂłn disponible en otros ectoparĂĄsitos, el microbioma del ĂĄcaro podrĂa participar en varios procesos biolĂłgicos y en la adquisiciĂłn, mantenimiento y transmisiĂłn de patĂłgenos. Sin embargo, se sabe poco sobre el papel del PRM como transportador mecĂĄnico o vector biolĂłgico en la transmisiĂłn de bacterias patĂłgenas. En este documento, utilizamos un enfoque de metaproteĂłmica para caracterizar las alfaproteobacterias en la microbiota de PRM y las variaciones en su perfil con el desarrollo de ectoparĂĄsitos (ninfas frente a adultos) y la alimentaciĂłn (sin alimentar frente a alimentados). Los resultados mostraron que la comunidad bacteriana asociada con D. gallinaeestaba compuesta principalmente por bacterias ambientales y comensales. Se identificaron bacterias simbiĂłticas putativas de los gĂŠneros Wolbachia, C. Tokpelaia y Sphingomonas , junto con bacterias patĂłgenas potenciales de los gĂŠneros Inquilinus , Neorickettsia y Roseomonas. Se asociaron diferencias significativas en la composiciĂłn de la microbiota alfaproteobacteriana con el desarrollo y la alimentaciĂłn de los ĂĄcaros, lo que sugiere que las bacterias tienen implicaciones funcionales en las vĂas metabĂłlicas asociadas con la alimentaciĂłn con sangre. Estos resultados apoyan el uso de la metaproteĂłmica para la caracterizaciĂłn de alfaproteobacterias asociadas a D. gallinaemicrobiota que podrĂa proporcionar informaciĂłn relevante para la comprensiĂłn de las interacciones ĂĄcaro-huĂŠsped y el desarrollo de posibles intervenciones de control
The histone binding capacity of SPT2 controls chromatin structure and function in Metazoa
Histone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans ortholog of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 null mutants display signatures of a global stress response. Genome-wide profiling showed that CeSPT-2 binds to a range of highly expressed genes, and we find that spt-2 mutants have increased chromatin accessibility at a subset of these loci. We also show that SPT2 influences chromatin structure and controls the levels of soluble and chromatin-bound H3.3 in human cells. Our work reveals roles for SPT2 in controlling chromatin structure and function in Metazoa.</p
Rucaparib maintenance treatment for recurrent ovarian carcinoma after response to platinum therapy (ARIEL3): a randomised, double-blind, placebo-controlled, phase 3 trial
Background:
Rucaparib, a poly(ADP-ribose) polymerase inhibitor, has anticancer activity in recurrent ovarian carcinoma harbouring a BRCA mutation or high percentage of genome-wide loss of heterozygosity. In this trial we assessed rucaparib versus placebo after response to second-line or later platinum-based chemotherapy in patients with high-grade, recurrent, platinum-sensitive ovarian carcinoma.
Methods:
In this randomised, double-blind, placebo-controlled, phase 3 trial, we recruited patients from 87 hospitals and cancer centres across 11 countries. Eligible patients were aged 18 years or older, had a platinum-sensitive, high-grade serous or endometrioid ovarian, primary peritoneal, or fallopian tube carcinoma, had received at least two previous platinum-based chemotherapy regimens, had achieved complete or partial response to their last platinum-based regimen, had a cancer antigen 125 concentration of less than the upper limit of normal, had a performance status of 0â1, and had adequate organ function. Patients were ineligible if they had symptomatic or untreated central nervous system metastases, had received anticancer therapy 14 days or fewer before starting the study, or had received previous treatment with a poly(ADP-ribose) polymerase inhibitor. We randomly allocated patients 2:1 to receive oral rucaparib 600 mg twice daily or placebo in 28 day cycles using a computer-generated sequence (block size of six, stratified by homologous recombination repair gene mutation status, progression-free interval after the penultimate platinum-based regimen, and best response to the most recent platinum-based regimen). Patients, investigators, site staff, assessors, and the funder were masked to assignments. The primary outcome was investigator-assessed progression-free survival evaluated with use of an ordered step-down procedure for three nested cohorts: patients with BRCA mutations (carcinoma associated with deleterious germline or somatic BRCA mutations), patients with homologous recombination deficiencies (BRCA mutant or BRCA wild-type and high loss of heterozygosity), and the intention-to-treat population, assessed at screening and every 12 weeks thereafter. This trial is registered with ClinicalTrials.gov, number NCT01968213; enrolment is complete.
Findings:
Between April 7, 2014, and July 19, 2016, we randomly allocated 564 patients: 375 (66%) to rucaparib and 189 (34%) to placebo. Median progression-free survival in patients with a BRCA-mutant carcinoma was 16¡6 months (95% CI 13¡4â22¡9; 130 [35%] patients) in the rucaparib group versus 5¡4 months (3¡4â6¡7; 66 [35%] patients) in the placebo group (hazard ratio 0¡23 [95% CI 0¡16â0¡34]; p<0¡0001). In patients with a homologous recombination deficient carcinoma (236 [63%] vs 118 [62%]), it was 13¡6 months (10¡9â16¡2) versus 5¡4 months (5¡1â5¡6; 0¡32 [0¡24â0¡42]; p<0¡0001). In the intention-to-treat population, it was 10¡8 months (8¡3â11¡4) versus 5¡4 months (5¡3â5¡5; 0¡36 [0¡30â0¡45]; p<0¡0001). Treatment-emergent adverse events of grade 3 or higher in the safety population (372 [99%] patients in the rucaparib group vs 189 [100%] in the placebo group) were reported in 209 (56%) patients in the rucaparib group versus 28 (15%) in the placebo group, the most common of which were anaemia or decreased haemoglobin concentration (70 [19%] vs one [1%]) and increased alanine or aspartate aminotransferase concentration (39 [10%] vs none).
Interpretation:
Across all primary analysis groups, rucaparib significantly improved progression-free survival in patients with platinum-sensitive ovarian cancer who had achieved a response to platinum-based chemotherapy. ARIEL3 provides further evidence that use of a poly(ADP-ribose) polymerase inhibitor in the maintenance treatment setting versus placebo could be considered a new standard of care for women with platinum-sensitive ovarian cancer following a complete or partial response to second-line or later platinum-based chemotherapy.
Funding:
Clovis Oncology
A preliminary assessment on use of biochar as a soil additive for reducing the soil-to-plant update of cesium isotopes in radioactively contaminated environments
peer-reviewedA series of Kd tracer batch experiments were conducted to assess the absorptive-desorption properties of Biochar as a potential agent to selectively sequester labile soil Cs or otherwise help reduce the uptake of Cs isotopes into plants. A parallel experiment was conducted for strontium. Fine-grained fractionated Woodlands tree Biochar was found to have a relatively high affinity for Cs ions (Kd > 100) in comparison with untreated coral soil (Kd < 10) collected from the Marshall Islands. The Biochar material also contains an abundance of K (and Mg). These findings support a hypothesis that the addition of Biochar as a soil amendment may provide a simple yet effective method for reducing the soil-to-plant transfer of Cs isotopes in contaminated environments
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV
The production of b jets in association with a Z/gamma* boson is studied
using proton-proton collisions delivered by the LHC at a centre-of-mass energy
of 7 TeV and recorded by the CMS detector. The inclusive cross section for
Z/gamma* + b-jet production is measured in a sample corresponding to an
integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross
section with Z/gamma* to ll (where ll = ee or mu mu) for events with the
invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level
with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and
the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.)
+(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also
studied and found to be in agreement with the predictions made by the MadGraph
event generator with the parton shower and the hadronisation performed by
PYTHIA.Comment: Submitted to the Journal of High Energy Physic
Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks
produced singly or in pairs in a data set corresponding to an integrated
luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in
2011. A novel strategy has been developed for a combined search for quarks of
the up and down type in decay channels with at least one isolated muon or
electron. Limits on the mass of the fourth-generation quarks and the relevant
Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a
simple extension of the standard model with a sequential fourth generation of
fermions. The existence of mass-degenerate fourth-generation quarks with masses
below 685 GeV is excluded at 95% confidence level for minimal off-diagonal
mixing between the third- and the fourth-generation quarks. With a mass
difference of 25 GeV between the quark masses, the obtained limit on the masses
of the fourth-generation quarks shifts by about +/- 20 GeV. These results
significantly reduce the allowed parameter space for a fourth generation of
fermions.Comment: Replaced with published version. Added journal reference and DO
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