254 research outputs found
Effect of soundscape dimensions on acoustic comfort in urban open public spaces
Soundscapes in public squares play important roles in urban open spaces. This study aimed to discover the effect of four soundscape dimensions, namely relaxation, communication, spatiality and dynamics, on acoustic comfort in urban open public spaces. A typical city square in China was selected as a case site. Sound environment measurements and questionnaire surveys were carried out for 8 survey positions. The results showed that the perceived dominance of sound sources had a significant effect on relaxation, communication, spatiality and dynamics. Relaxation was greater when the natural sound was perceived dominantly, while it was lower when mechanical sounds or anthropogenic sounds were perceived dominantly. Acoustic comfort had a significant correlation with the soundscape dimensions and LAeq, with spearman's correlation coefficients of 0.495 (relaxation), 0.210 (sound pressure level) and 0.288 (spatiality). In terms of the differences in perceived sound types, acoustic comfort was positively correlated with relaxation when natural sound or anthropogenic sound was perceived dominantly. As spatiality increased, acoustic comfort first decreased and later increased when relaxation was higher, while there were positive correlations between acoustic comfort and relaxation under the other situations. Moreover, when spatiality or communication was higher, there were significant correlations between acoustic comfort and dynamics. According to these results, acoustic comfort can be increased as soundscape dimensions change in an urban open public space
Working conditions and public health risks in slaughterhouses in western Kenya
Background: Inadequate facilities and hygiene at slaughterhouses can result in contamination of meat and
occupational hazards to workers. The objectives of this study were to assess current conditions in slaughterhouses
in western Kenya and the knowledge, and practices of the slaughterhouse workers toward hygiene and sanitation.
Methods: Between February and October 2012 all consenting slaughterhouses in the study area were recruited.
A standardised questionnaire relating to facilities and practices in the slaughterhouse was administered to the
foreperson at each site. A second questionnaire was used to capture individual slaughterhouse workersâ knowledge,
practices and recent health events.
Results: A total of 738 slaughterhouse workers from 142 slaughterhouses completed questionnaires. Many
slaughterhouses had poor infrastructure, 65% (95% CI 63â67%) had a roof, cement floor and walls, 60%
(95% CI 57â62%) had a toilet and 20% (95% CI 18â22%) had hand-washing facilities. The meat inspector
visited 90% (95% CI 92â95%) of slaughterhouses but antemortem inspection was practiced at only 7% (95% CI 6â8%).
Nine percent (95% CI 7â10%) of slaughterhouses slaughtered sick animals. Only half of workers wore personal
protective clothing - 53% (95% CI 51â55%) wore protective coats and 49% (95% CI 46â51%) wore rubber boots.
Knowledge of zoonotic disease was low with only 31% (95% CI 29â33%) of workers aware that disease could be
transmitted from animals.
Conclusions: The current working conditions in slaughterhouses in western Kenya are not in line with the
recommendations of the Meat Control Act of Kenya. Current facilities and practices may increase occupational
exposure to disease or injury and contaminated meat may enter the consumer market. The findings of this study
could enable the development of appropriate interventions to minimise public health risks. Initially,
improvements need to be made to facilities and practices to improve worker safety and reduce the risk of food
contamination. Simultaneously, training programmes should target workers and inspectors to improve awareness
of the risks. In addition, education of health care workers should highlight the increased risks of injury and
disease in slaughterhouse workers. Finally, enhanced surveillance, targeting slaughterhouse workers could be
used to detect disease outbreaks. This âOne Healthâ approach to disease surveillance is likely to benefit workers,
producers and consumers
Hepcidin Is Involved in Iron Regulation in the Ischemic Brain
Oxidative stress plays an important role in neuronal injuries caused by cerebral ischemia. It is well established that free iron increases significantly during ischemia and is responsible for oxidative damage in the brain. However, the mechanism of this ischemia-induced increase in iron is not completely understood. In this report, the middle cerebral artery occlusion (MCAO) rat model was performed and the mechanism of iron accumulation in cerebral ischemia-reperfusion was studied. The expression of L-ferritin was significantly increased in the cerebral cortex, hippocampus, and striatum on the ischemic side, whereas H-ferritin was reduced in the striatum and increased in the cerebral cortex and hippocampus. The expression level of the iron-export protein ferroportin1 (FPN1) significantly decreased, while the expression of transferrin receptor 1 (TfR1) was increased. In order to elucidate the mechanisms of FPN1 regulation, we studied the expression of the key regulator of FPN1, hepcidin. We observed that the hepcidin level was significantly elevated in the ischemic side of the brain. Knockdown hepcidin repressed the increasing of L-ferritin and decreasing of FPN1 invoked by ischemia-reperfusion. The results indicate that hepcidin is an important contributor to iron overload in cerebral ischemia. Furthermore, our results demonstrated that the levels of hypoxia-inducible factor-1α (HIF-1α) were significantly higher in the cerebral cortex, hippocampus and striatum on the ischemic side; therefore, the HIF-1α-mediated TfR1 expression may be another contributor to the iron overload in the ischemia-reperfusion brain
A Criterion for Brittle Failure of Rocks Using the Theory of Critical Distances
This paper presents a new analytical criterion for brittle failure of rocks and heavily overconsolidated soils. Griffithâs model of a randomly oriented defect under a biaxial stress state is used to keep the criterion simple. The Griffithâs criterion is improved because the maximum tensile strength is not evaluated at the boundary of the defect but at a certain distance from the boundary, known as the critical distance. This fracture
criterion is known as the Point Method, and is part of the Theory of Critical Distances, which is utilized in fracture mechanics. The proposed failure criterion has two parameters: the inherent tensile strength, Ăł0, and the ratio of the half-length of the initial crack/flaw to the critical distance, a/L. These parameters are difficult to measure but they may be correlated with the uniaxial compressive and tensile strengths, Ăłc and Ăłt.
The proposed criterion is able to reproduce the common range of strength ratios for rocks and heavily overconsolidated soils (Ăłc/Ăłt=3-50) and the influence of several microstructural rock properties, such as texture and porosity. Good agreement with laboratory tests reported in the literature is found for tensile and low confining stresses.The work presented was initiated during a research project on âStructural integrity
assessments of notch-type defects", for the Spanish Ministry of Science and Innovation
(Ref.: MAT2010-15721)
In silico exploration of Red Sea Bacillus genomes for natural product biosynthetic gene clusters
Background: The increasing spectrum of multidrug-resistant bacteria is a major global public health concern, necessitating discovery of novel antimicrobial agents. Here, members of the genus Bacillus are investigated as a potentially attractive source of novel antibiotics due to their broad spectrum of antimicrobial activities. We specifically focus on a computational analysis of the distinctive biosynthetic potential of Bacillus paralicheniformis strains isolated from the Red Sea, an ecosystem exposed to adverse, highly saline and hot conditions. Results: We report the complete circular and annotated genomes of two Red Sea strains, B. paralicheniformis Bac48 isolated from mangrove mud and B. paralicheniformis Bac84 isolated from microbial mat collected from Rabigh Harbor Lagoon in Saudi Arabia. Comparing the genomes of B. paralicheniformis Bac48 and B. paralicheniformis Bac84 with nine publicly available complete genomes of B. licheniformis and three genomes of B. paralicheniformis, revealed that all of the B. paralicheniformis strains in this study are more enriched in nonribosomal peptides (NRPs). We further report the first computationally identified trans-acyltransferase (trans-AT) nonribosomal peptide synthetase/polyketide synthase (PKS/ NRPS) cluster in strains of this species. Conclusions:B. paralicheniformis species have more genes associated with biosynthesis of antimicrobial bioactive compounds than other previously characterized species of B. licheniformis, which suggests that these species are better potential sources for novel antibiotics. Moreover, the genome of the Red Sea strain B. paralicheniformis Bac48 is more enriched in modular PKS genes compared to B. licheniformis strains and other B. paralicheniformis strains. This may be linked to adaptations that strains surviving in the Red Sea underwent to survive in the relatively hot and saline ecosystems
Ethnic Related Selection for an ADH Class I Variant within East Asia
The alcohol dehydrogenases (ADH) are widely studied enzymes and the evolution of the mammalian gene cluster encoding these enzymes is also well studied. Previous studies have shown that the ADH1B*47His allele at one of the seven genes in humans is associated with a decrease in the risk of alcoholism and the core molecular region with this allele has been selected for in some East Asian populations. As the frequency of ADH1B*47His is highest in East Asia, and very low in most of the rest of the world, we have undertaken more detailed investigation in this geographic region.Here we report new data on 30 SNPs in the ADH7 and Class I ADH region in samples of 24 populations from China and Laos. These populations cover a wide geographic region and diverse ethnicities. Combined with our previously published East Asian data for these SNPs in 8 populations, we have typed populations from all of the 6 major linguistic phyla (Altaic including Korean-Japanese and inland Altaic, Sino-Tibetan, Hmong-Mien, Austro-Asiatic, Daic, and Austronesian). The ADH1B genotyping data are strongly related to ethnicity. Only some eastern ethnic phyla or subphyla (Korean-Japanese, Han Chinese, Hmong-Mien, Daic, and Austronesian) have a high frequency of ADH1B*47His. ADH1B haplotype data clustered the populations into linguistic subphyla, and divided the subphyla into eastern and western parts. In the Hmong-Mien and Altaic populations, the extended haplotype homozygosity (EHH) and relative EHH (REHH) tests for the ADH1B core were consistent with selection for the haplotype with derived SNP alleles. In the other ethnic phyla, the core showed only a weak signal of selection at best.The selection distribution is more significantly correlated with the frequency of the derived ADH1B regulatory region polymorphism than the derived amino-acid altering allele ADH1B*47His. Thus, the real focus of selection may be the regulatory region. The obvious ethnicity-related distributions of ADH1B diversities suggest the existence of some culture-related selective forces that have acted on the ADH1B region
Test of lepton universality in decays
The first simultaneous test of muon-electron universality using
and decays is performed, in two ranges of the dilepton
invariant-mass squared, . The analysis uses beauty mesons produced in
proton-proton collisions collected with the LHCb detector between 2011 and
2018, corresponding to an integrated luminosity of 9 . Each
of the four lepton universality measurements reported is either the first in
the given interval or supersedes previous LHCb measurements. The
results are compatible with the predictions of the Standard Model.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-046.html (LHCb
public pages
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