10 research outputs found

    Influence of T shape baffles arrangement on flow hydraulic characteristics in fishways

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    Hydraulic structures constructed along the rivers cause disturbances in the natural process of aquatic life and the ecosystem of the region. In order to solve this problem, fishway structure is widely used to facilitate the communication path between downstream and upstream of hydraulic structures crossing the river and to eliminate the inability of fish to swim upstream and also to facilitate their movement downstream of dams. The different types of this structure should be designed to absorb the type of migratory fish in the area and to pass them safely and out of the outlet, without injuring the fish or creating unnecessary delays for the adult spawning fish. Therefore, in the present study, in order to determine the optimal configuration of the T shape baffles used in the path, three types of arrangements were numerically simulated using OpenFOAM software and K-ε turbulence model. These three types of arrangements are consecutive, alternate and also reversed. Then, the results of the numerical model were validated by comparing it with the results of the related laboratory model. The findings indicate that the numerical model is in good agreement with the laboratory results. Among the three configurations, taking into account different factors, the reverse location of T-shaped baffles with 68.3% backwater, 86.2% flow at less than 0.5 m/s, 84.1% turbulent kinetic energy values less than 0.02 square meters per square second and also 61% energy dissipation percentage, had the best performance

    The effects of saffron (Crocus sativus L.) on mental health parameters and C-reactive protein: A meta-analysis of randomized clinical trials

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    Background: The findings of trials investigating the effects of saffron (Crocus sativus L.) supplementation on depression, anxiety, and C-reactive protein (CRP) are inconsistent. The current meta-analysis of randomized controlled trials (RCTs) was carried out to assess the effects of saffron (Crocus sativus L.) administration on mental health parameters and CRP levels. Methods: Two independent authors systematically searched online databases including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until 30th July 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I-square (I2) statistic. Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. Results: Twenty one trials were included in this meta-analysis. Consumption of saffron resulted in a significant reduction in Beck Depression Inventory (BDI) (11 studies with 12 effect size) (WMD: �4.86; 95 CI: �6.58, �3.14), Beck Anxiety Inventory (BAI) (5 studies) (WMD: �5.29; 95 CI: �8.27, �2.31) and Pittsburgh Sleep Quality Index (PSQI) scores (3 studies with 4 effect size) (WMD: �2.22; 95 CI: �2.73, �1.72). Saffron intake did not affect Hamilton Depression Rating Scale (HDRS-D), Hamilton Anxiety Rating Scale (HARS-A) scores and C-reactive protein (CRP) levels. Conclusions: This meta-analysis demonstrated that saffron intake significantly reduced BDI, BAI and PSQI scores, but did not affect HDRS-D, HARS-A scores and CRP levels. © 2019 Elsevier Lt

    A three-dimensional study of flow characteristics over different forms of stepped–labyrinth spillways in the skimming flow regime

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    To improve the performance of stepped spillways, their combination with labyrinth spillways is an interesting topic. In this study, several labyrinth configurations of stepped spillways were presented. Validation of the numerical model was done using the results of the previous physical models. After that, three configurations including: conventional stepped, trapezoidal-labyrinth, and rectangular-labyrinth were modeled using the OpenFOAM model for the skimming flow regime. For simulation, the InterFOAM solver and RNG k–ε turbulence model were used. The results showed an increase of 34.7 and 21.1% in energy dissipation in the trapezoidal and rectangular stepped–labyrinth spillways compared to the conventional stepped type, for dc/h = 1.45 (the range of dc is between 8 and 14.5 cm). The flow velocity in the end step of the trapezoidal- and rectangular-labyrinth configuration is reduced by 50.5 and 31.1%, respectively. Furthermore, in the trapezoidal configuration, a 14.7% reduction in flow velocity has been achieved compared to the rectangular stepped–labyrinth configuration. The results showed that the minimum pressure on the vertical faces of the steps occurred in their upper half and the rectangular configuration has resulted in the highest amount of negative pressure. The turbulence kinetic energy, especially in trapezoidal configuration, has increased toward the downstream. HIGHLIGHTS The combination of stepped and labyrinth spillways is effective in improving the performance of spillways in terms of energy dissipation.; The trapezoidal stepped–labyrinth combined spillway has the best performance among the combined spillways in terms of energy dissipation.; The minimum pressure on the horizontal face of the steps occurred in the central axis and the maximum occurred near the outer edge of the steps.

    Investigation of the Necessity of Petroff Method for More Accurate Diagnosis of Tuberculosis in Tuberculosis Reference Laboratory of Hamadan Province, Iran, During the COVID-19 Pandemic

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    Background and Objective: A definitive diagnosis of tuberculosis is based on the identification of tubercle bacilli in sputum using microscopy and culture. Although direct smear microscopy is the most common diagnostic method, the Petroff method is recommended for a better diagnosis of tuberculosis. This study aimed to evaluate the Petroff method for a more accurate diagnosis of tuberculosis in health centers of Hamadan province, Iran, during the COVID-19 pandemic. Materials and Methods: In this descriptive cross-sectional study, 210 sputum specimens from patients who were referred to the tuberculosis reference laboratory in Hamadan province were collected in health centers. All of the samples were processed for the presence of mycobacteria using the Petroff method and the direct smear technique, and the results of both techniques were compared afterward. Results: Among 210 samples, 9 (4.28%) and 12 (5.71%) cases were reported as smear-positive samples by direct smear method and Petroff method, respectively. A comparison of the results showed that the sensitivity for acid-fast bacilli (AFB) smears was increased using the Petroff method. Conclusion: Petroff method improved the sensitivity of AFB identification. It was methodologically simpler and less expensive and can be used as a promising candidate in primary TB control programs. Therefore, we recommend the Petroff method for the improvement of the sensitivity of AFB microscopy

    Population-level risks of alcohol consumption by amount, geography, age, sex, and year : a systematic analysis for the Global Burden of Disease Study 2020

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    Background: The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods: For this analysis, we constructed burden-weighted dose–response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15–95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings: The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15–39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0–0) and 0·603 (0·400–1·00) standard drinks per day, and the NDE varied between 0·002 (0–0) and 1·75 (0·698–4·30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0·114 (0–0·403) to 1·87 (0·500–3·30) standard drinks per day and an NDE that ranged between 0·193 (0–0·900) and 6·94 (3·40–8·30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59·1% (54·3–65·4) were aged 15–39 years and 76·9% (73·0–81·3) were male. Interpretation: There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Funding: Bill &amp; Melinda Gates Foundation.</p

    Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020

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    Background The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods For this analysis, we constructed burden-weighted dose-response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15-95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15-39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0-0) and 0.603 (0.400-1.00) standard drinks per day, and the NDE varied between 0.002 (0-0) and 1.75 (0.698-4.30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0.114 (0-0.403) to 1.87 (0.500-3.30) standard drinks per day and an NDE that ranged between 0.193 (0-0.900) and 6.94 (3.40-8.30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59.1% (54.3-65.4) were aged 15-39 years and 76.9% (73.0-81.3) were male. Interpretation There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol

    Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020

    Get PDF
    Background: The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods: For this analysis, we constructed burden-weighted dose–response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15–95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings: The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15–39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0–0) and 0·603 (0·400–1·00) standard drinks per day, and the NDE varied between 0·002 (0–0) and 1·75 (0·698–4·30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0·114 (0–0·403) to 1·87 (0·500–3·30) standard drinks per day and an NDE that ranged between 0·193 (0–0·900) and 6·94 (3·40–8·30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59·1% (54·3–65·4) were aged 15–39 years and 76·9% (73·0–81·3) were male. Interpretation: There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Funding: Bill & Melinda Gates Foundation
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