142 research outputs found

    The cosmological bulk flow in QCDM model: (In)consistency with ΛCDM\Lambda CDM

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    We study the bulk flow of the local universe using Type Ia supernova data by considering a class of cosmological model which is spatially flat,(FRW) space-times and contains cold dark matter and QQ component (QCDM models) of the fluid as a scalar field, with self interactions determined by a potential V(Q)=V0Exp(λQ)V(Q)=V_{0}Exp(-\lambda Q) evolving in Universe. We use different cumulative redshift slices of the Union 2 catalogue. A maximum-likelihood analysis of peculiar velocities confirms that at low redshift 0.015<z<0.10.015 <z<0.1, bulk flow is moving towards the (l;b)=(302o±20o;3o±10o)(l; b) = (302^{o}\pm20^{o}; 3^{o}\pm10^{o}) direction with vbulk=240±25kms1v _{bulk} = 240\pm 25kms^{-1} velocity. This direction is aligned with direction of (SSC) and agreement with a number previous studies at (1σ)(1-\sigma), however for high redshift 0.1<z<0.20.1 <z<0.2, we get vbulk=1000±25kms1v _{bulk} = 1000\pm 25kms^{-1} towards the (l;b)=(25414o+16o;610o+7o)(l; b) = (254^{+16^{o}}_{-14^{o}}; 6^{+7^{o}}_{-10^{o}}). This indicates that for low redshift our results are approximately consistent with the ΛCDM\Lambda CDM model with the latest WMAP best fit cosmological parameters however for high redshift they are in disagreement of ΛCDM\Lambda CDM and support the results of previous studies such as Kashlinsky et. al, which report the large bulk flow for the Universe. We can conclude that, in QCDMQCDM model, at small scales, fluctuations of the dark energy are damped and do not enter in the evolution equation for the perturbations in the pressureless matter, while at very large scales (>100h1Mpc)(\sim > 100 h^{-1}Mpc), they leaving an imprint on the microwave background anisotropy

    Photometric Stereo with Non-Lambertian Preprocessing and Hayakawa Lighting Estimation for Highly Detailed Shape Reconstruction

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    In many realistic scenarios, the use of highly detailed photometric 3D reconstruction techniques is hindered by several challenges in given imagery. Especially, the light sources are often unknown and need to be estimated, and the light reflectance is often non-Lambertian. In addition, when approaching the problem to apply photometric techniques at real-world imagery, several parameters appear that need to be fixed in order to obtain high-quality reconstructions. In this chapter, we attempt to tackle these issues by combining photometric stereo with non-Lambertian preprocessing and Hayakawa lighting estimation. At hand of a dedicated study, we discuss the applicability of these techniques for their use in automated 3D geometry recovery for 3D printing

    Spatial and temporal trends of short-term health impacts of PM2.5in Iranian cities; A modelling approach (2013�2016)

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    Estimation of the spatial and temporal trends of health impacts attributable to air pollution is an effective measure for evaluating implemented interventions. The aim of this study was to estimate the short-term mortality attributable to exposure to PM2.5among individuals older than 30 years old in ten Iranian cities from March 2013 to March 2016 using the World Health Organization�s (WHO) AirQ+ software. Hourly concentrations of PM2.5were acquired from the Department of Environment and Tehran Air Quality Control Company. Only stations with 75 and 50 of valid data were qualified for Tehran and other cities, respectively. The annual average PM2.5concentrations in all ten of the cities were higher than the WHO guideline value of 10 µg m�3The total number of attributable short-term deaths during the three-year period in these 10 cities was 3284 (95 CI: 1207�5244). The average daily premature deaths were calculated to be 3. The highest number of premature deaths within the three-year period was estimated to be 548 in Tehran, largely reflecting its population of nearly 9 million. The western and southern cities of Iran experience severe dust storms and showed a high estimated rate of death attributed to air pollution. The health impacts in all cities decreased in the third year compared to the first year except for Ahvaz, Khoram Abad, and Ilam. Governmental interventions need to be enforced more effectively to reduce the high level of adverse health impacts in Iran. Special considerations should be given to the air quality of cities affected by dust storms. © Taiwan Association for Aerosol Research

    Design and evaluation of the performance of local exhaust hood on the welding torch

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    Background and aims: Threats against welders' health due to exposure to welding fume is an important issue; thus, controlling and examining effective exhaust of fumes are necesary. In this study, was evaluated prototype operation of local exhaust ventilation on-gun in bench scale. Methods: Duct velocity average was determined using traverse points method and calculated flow rate by hood using ACGIH standard method. Also capture velocity close in contaminant source (Arc Point) was measured using thermal anemometer. Then, in order to determine total particles concentration and capture efficiency created by system NIOSH 7200 standard method was used. Results: Duct velocity average and created flow rate by evaluated system were 6296.1±92.50 fpm and 34.06±0/50 scfm, respectively. Also, capture velocity in close of the weld point was obtained 140 fpm. Sampling results for averaged total particles concentration in off and on positions of system were 75±7 mg/m3 and 16.7±4 mg/m3, respectively. As a result, 77 containment efficiency was achieved by this system. Conclusion: The local exhaust ventilation used in this study was a low cost prototype and according to the acheived results, it leads to reduce total particles concentration (T.P) in breathing zone aproximately to 22

    Correction to: Indoor and outdoor concentrations of BTEX and formaldehyde in Tehran, Iran: effects of building characteristics and health risk assessment (Environmental Science and Pollution Research, (2018), 10.1007/s11356-018-2794-4)

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    The original publication of this paper contains a mistake. The correct name and affiliation of the 3rd Author is presented in this paper. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature

    Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing

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    A systematic review and meta-analysis of human biomonitoring studies on exposure to environmental pollutants in Iran

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    Population exposure to environmental contaminants can be precisely observed through human biomonitoring studies. The present study aimed to systematically review all the biomonitoring studies conducted in Iran on some selected carcinogen environmental pollutants. In this systematic review study, 11 carcinogen agents were selected including arsenic, cadmium, chromium, nickel, lindane, benzene, trichloroethylene (TCE), pentachlorophenol (PCP), radon-222, radium-224, � 226, � 228, and tobacco smoke. The Web of Science, PubMed, and Scopus databases were searched for peer-reviewed articles published in English. After several screening steps, data were extracted from the studies. Meta-analyses (a random-effect model using the DerSimonian-Laired method) were performed only for the biomarkers with more than three eligible articles, including cadmium in blood and breast milk, and arsenic in breast milk. Methodological quality of the studies was assessed using the Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies. Of the 610 articles found in the database search, 30 studies were eligible for qualitative review, and 13 were included in the meta-analysis (cadmium in blood (n = 3), cadmium in breast milk (n = 6), and arsenic in breast milk (n = 4)). The overall pooled average concentrations (95 CI) of cadmium in blood, cadmium in breast milk, and arsenic in breast milk were 0.11 (95 CI: 0.08, 0.14), 5.38 (95 CI: 3.60, 6.96), and 1.42 (95 CI: 1.02, 1.81) µg/L, respectively. These values were compared with the biomarker concentrations in other countries and health-based guideline values. This study showed that there is a need for comprehensive action plans to reduce the exposure of general population to these environmental contaminants. © 202

    Supply and protected different population of Litopenaeus vannamei subadult zero foster (F0) from difference provinces Iran

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    Nowadays, Litopenaeus vannamei are the most important species of farmed penaeidae shrimp in the world that is rapidly replacing native species in areas aquaculture. Due to demand increase for this species culture, shrimp displacement to different areas may be associated with some potential pathogens transferred to new areas farmed. Therefore, in this study were prepared bi-osecurity conditions for specific disease-free production of L. vannamei. Thereafter, three populations (Molokaei, High health and mix of Molokaei and High health) of the shrimp various reserves were detected base on origin and genetic indexes such as: observed heterozygosity, expected heterozygosity, allele frequency, coefficient inbreeding, genetic differentiation, genetic distance and genetic identity. On the other hand, epidemiological studies indicate non pathogens (viral, bacterial, fungal and parasitic) recognition of different populations selected in the quarantine salon. The bioassay results showed that the average weight and length of the populations of High health and Mix significantly greater than was a population of Molokaei. The shrimp populations were stocked in fiberglass tank (five ton) and were kept separated in the quarantine salon. During maintenance shrimp of populations in the quarantine salon were evaluated living and non-living pathogens with PCR, microbiology and biochemical methods. There is not any pathogens detection from shrimp populations stocking in the quarantine salon, so the shrimps were carried over to pond for broodstock culture of specific pathogenic free

    Changing expression of vertebrate immunity genes in an anthropogenic environment: a controlled experiment

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    Background: The effect of anthropogenic environments on the function of the vertebrate immune system is a problem of general importance. For example, it relates to the increasing rates of immunologically-based disease in modern human populations and to the desirability of identifying optimal immune function in domesticated animals. Despite this importance, our present understanding is compromised by a deficit of experimental studies that make adequately matched comparisons between wild and captive vertebrates. Results: We transferred post-larval fishes (three-spined sticklebacks), collected in the wild, to an anthropogenic (captive) environment. We then monitored, over 11 months, how the systemic expression of immunity genes changed in comparison to cohort-matched wild individuals in the originator population (total n = 299). We found that a range of innate (lyz, defbl2, il1r-like, tbk1)and adaptive (cd8a, igmh) immunity genes were up-regulated in captivity, accompanied by an increase in expression of the antioxidant enzyme, gpx4a. For some genes previously known to show seasonality in the wild, this appeared to be reduced in captive fishes. Captive fishes tended to express immunity genes, including igzh, foxp3b, lyz, defbl2, and il1r-like, more variably. Furthermore, although gene co-expression patterns (analyzed through gene-by-gene correlations and mutual information theory based networks) shared common structure in wild and captive fishes, there was also significant divergence. For one gene in particular, defbl2, high expression was associated with adverse health outcomes in captive fishes. Conclusion: Taken together, these results demonstrate widespread regulatory changes in the immune system in captive populations, and that the expression of immunity genes is more constrained in the wild. An increase in constitutive systemic immune activity, such as we observed here, may alter the risk of immunopathology and contribute to variance in health in vertebrate populations exposed to anthropogenic environments
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