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Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis 被引量:1
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作者 Seyed Sobhan Bahreiny Mojtaba Aghaei +3 位作者 Mohammad Reza Dabbagh Hamid Ghorbani Moslem Javidan Reza Mohammadpour Fard 《Asian pacific Journal of Reproduction》 CAS 2024年第1期12-21,共10页
Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the as... Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality parameters.This search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and Scopus.Pooled effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen samples.Results:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality parameters.In particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm parameters.Conclusions:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters. 展开更多
关键词 Semen quality Sulfur dioxide Ambient air pollution META-ANALYSIS
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Surface Water Quality Profiling Using Physicochemical Parameters in Open Defecation Free and Non-Open Defecation Free Local Government Areas in Benue State, Nigeria
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作者 Moses T. Asoo Celestine U. Aguoru +1 位作者 Innocent O. Ogbonna Hyacinth O.A. Oluma 《Open Journal of Modern Hydrology》 CAS 2024年第3期174-191,共18页
Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 ... Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 mg/L), Na (28.72 mg/L), Ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), TSS (6.27 mg/L), TDS (104.23 mg/L), BOD (2.83 mg/L) and F (0.87 mg/L) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTU), dissolved oxygen (DO) (5.32 mg/L), chemical oxygen demand (COD) (445.50 mg/L), K (125.06 mg/L), PO4 (0.78 mg/L) and Fe (0.57 mg/L) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pollution of the water sources by organic matter. 展开更多
关键词 Open Defecation Surface Water Water quality Standard Physicochemical parameters
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Exploring the Relationship between Spatiotemporal Variations in Air Quality and Meteorological Parameters before and during the COVID-19 Pandemic in Xi’an
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作者 Muhammad Sajid Mehmood Shiyan Zhai +2 位作者 Gang Li Yaochen Qin Vithana Pathirannehelage Indika Sandamali Wijeratne 《Journal of Geoscience and Environment Protection》 2024年第8期115-148,共34页
The COVID-19 pandemic has significantly changed the air pollution of the world. The present study investigated the temporal and spatial variability in air quality in Xi’an, China, and its relationship with meteorolog... The COVID-19 pandemic has significantly changed the air pollution of the world. The present study investigated the temporal and spatial variability in air quality in Xi’an, China, and its relationship with meteorological parameters during and before the COVID-19 pandemic. The outcomes of this study indicated that air pollutants, PM2.5, NO2, PM10, CO, and SO2 are likely to decrease during winter (25%, 50%, 30%, 40%, and 35%) to spring (30%, 55%, 38%, 50%, and 40%) and summer (40%, 58%, 60%, 55%, and 47%), respectively. However, the concentration of O3-8h increased by 40%, 55%, and 65% during winter, spring, and summer, respectively. The values of the air quality index decreased during the COVID-19 period. Furthermore, significant positive trends were reported in PM2.5, NO2, PM10, O3, and SO2, and no notable trends in CO during the COVID-19 pandemic. Both during and before the COVID-19 period, PM10, NO2, PM2.5, CO, and SO2 showed a negative correlation with the temperature and a moderately positive significant correlation between O3-8h and temperature. The findings of this study would help understand the air pollution circumstances in Xi’an before and during the COVID-19 period and offer helpful information regarding the implications of different air pollution control strategies. 展开更多
关键词 Spatiotemporal Analysis Air quality Index Meteorological parameters COVID-19
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Analysis of the Quality of Physical and Chemical Parameters of Groundwater in Three Localities in the Sub-Prefecture of Zanzra (Ivory Coast)
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作者 Djedjess Essoh Jules-César Meledje Bi Irié Marc Gouli +3 位作者 Drissa Ouattara Kra Vanh Eric-Simon Zran Adjourma Konate Albert Trokourey 《Journal of Materials Science and Chemical Engineering》 2024年第4期1-17,共17页
The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly Côte d’Ivoire. The State of Côte d’Ivoire and rural populations are building h... The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly Côte d’Ivoire. The State of Côte d’Ivoire and rural populations are building hydraulic infrastructure for this purpose. However, the quality of water coming from these infrastructures remains to be determined. This study therefore aims to analyze certain physicochemical parameters of the groundwater of Gloazra, Kouezra and Trahonfla. These are temperature, pH, electrical conductivity, TDS, salinity level, hardness, alkalinity, chloride content and bicarbonate. To determine the pH, electrical conductivity, temperature, TDS, and salinity rate, an electrochemical analysis was carried out. The titrimetric analysis made it possible to determine the chloride and bicarbonate content, alkalinity, and hardness. The results indicate that the studied groundwater is soft and acidic with good mineralization. This water does not present a health hazard to consumers but can affect hydraulic equipment and household containers. 展开更多
关键词 Ivory Coast Gloazra Trahonfla Kouezra Physicochemical parameters Water WHO Standards
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Assessing the Impact of Petrol Service Stations on Selected Physico-Chemical Water Quality Parameters within Port Harcourt Metropolis, Nigeria
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作者 William Azuka Iyama Obrieze Chekwa Nnadi +7 位作者 Ini Ubong Michael Nakara Timothy Chukwudi Osademe Dollah Yenor Lekie Gbode Chukwudi Omeni Egbunefu Woboroma Stella Emejuru Preye Nimame Williams Chinedu Onuegbu 《Journal of Geoscience and Environment Protection》 2024年第10期204-220,共17页
This study assessed the impact of petrol service stations on physico-chemical water quality in Port Harcourt metropolis, Rivers State. This threw light on the extent of damage and alteration of water quality in Port H... This study assessed the impact of petrol service stations on physico-chemical water quality in Port Harcourt metropolis, Rivers State. This threw light on the extent of damage and alteration of water quality in Port Harcourt metropolis as a result of the proliferation of petrol service stations especially the condition of ground and nearby surface water. This serves as a useful tool to government and regulatory authorities for planning especially due to lack of central water supply system in Port Harcourt metropolis. The parameters studied were sampled, measured and analyzed using in situ and other standard methods. Remarkable results above permissible limits of interest for physicochemical parameter analysis revealed pH values from 4.6 to 6.8, electrical conductivity from 0.002 µS/cm to 0.42 µS/cm, salinity from 3 ppm to 4050 ppm, and temperatures from 19.9˚C to 32.6˚C. Total dissolved solids (TDS) varied from 7 ppm to 1000 ppm, biochemical oxygen demand (BOD) from 0.167 mg/L to 2.167 mg/L, chemical oxygen demand (COD) from 0.257 mg/L to 3.253 mg/L, and dissolved oxygen (DO) concentrations from 1.70 mg/L to 4.30 mg/L. Specifically, water samples from NNPC Filling Station (Choba) and Eneka Pond displayed “Poor” water quality with WQI values of 112.003 and 112.076, respectively. Similarly, ALLTEC Filling Station (Eneka) and TOTAL Filling Station (Rumuomasi) had “Poor” water quality with WQI values of 173.707 and 180.946, respectively. In contrast, Excelsis Filling Station (Akpajo) demonstrated “Good” water quality with a WQI of 85.2072, while Total Filling Stations (Slaughter) and Choba River revealed “unsuitable for drinking” water quality with WQI values of 552.461 and 654.601, respectively. Slaughter River also indicated very poor water quality with a WQI of 442.024. The physicochemical and nutrient analyses of the water samples showed that activities of the filling stations within the study area may have polluted groundwater in the environment posing poor aesthetics and great health risk to consumers of the water bodies. The findings underscore the need for immediate remediation efforts and stricter regulatory measures to protect water quality. The study concluded that surface and groundwater near petrol service stations in Port Harcourt are unfit for drinking and irrigation purposes without adequate treatment. 展开更多
关键词 Water quality Index Petrol Service Stations Contamination Environmental Impact Assessment Eneka Drilling Points
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Investigating the Air Quality Parameters in Louisiana’s Industrial Corridor: A Baton Rouge Case Study
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作者 Oluwafemi Awolesi Peter G. Oni +5 位作者 Oluwatoyin K. Adekoya Seyi B. Adekoya Oluwafeyikemi D. Ogunmusi Fatemeh Ghafari Abosede Oje Odunayo Lawal 《Journal of Geoscience and Environment Protection》 2024年第7期139-164,共26页
In a local context, sustainable development entails utilizing the current resources—material and immaterial, measurable and immeasurable, popular and unpopular—of the community in a manner that avoids overexploitati... In a local context, sustainable development entails utilizing the current resources—material and immaterial, measurable and immeasurable, popular and unpopular—of the community in a manner that avoids overexploitation and ensures intergenerational equity. This approach prioritizes the safety and health of local citizens, placing communal productivity above corporate profitability. This research aims to assess air quality surrounding 28 chemical industry sites in Baton Rouge, Louisiana, to understand the environmental and health impacts of industrial pollutants, with a focus on environmental justice. Air quality pollutants, including PM2.5, PM10, O3, NO2, CO, and SO2, were monitored for 75 days during the Summer, using the BreezoMeter app. Python, Mapize, and QGIS software technologies were utilized for data analysis and visualization. Findings indicate a reduction in NO2 and CO levels, compared to existing literature. However, the persistent challenge of particulate matter suggests areas for further environmental management efforts. Additionally, the research suggests a significant disparity in air pollution exposure, probably affecting marginalized communities. Although the nature of the study might not fully capture annual pollution trends, the findings highlight the urgent need for the chemical industry to adopt efficient production methods and for policymakers to enhance air quality standards and enforcement, particularly in pollution-sensitive areas. The disproportionate impact of air pollution on vulnerable communities calls for a more inclusive approach to environmental justice, ensuring equitable distribution of clean air benefits and community involvement in pollution management decisions. 展开更多
关键词 Air quality Monitoring Chemical Industry Pollution Environmental Justice Health Implications Particulate Matter Case Study
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Effect of Main Cultivation Factors on Quality Combination Parameters of High-quality Brassica napus Hybrids 被引量:4
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作者 赵继献 王仙平 高志宏 《Agricultural Science & Technology》 CAS 2013年第5期738-749,753,共13页
[Objective] This study aimed to analyze the influence of five cultivation factors including sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on the quali... [Objective] This study aimed to analyze the influence of five cultivation factors including sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on the quality parameters of Brassica napus hybrid& [Method] Statistical analysis on the data from previous studies and our work was carried out [Result] The contents of erucic acid, thioglycoside, oil, oleic acid and linoleic acid were negatively correlated with the sowing date, while the contents of seed protein, palmitic acid, stearic acid and linolenic acid were positively correlated with the sowing date. The total amount of fat and protein, the ratio of unsaturated fatty acid (UFA) to saturated fatty acid (SFA), the fatty acid (FA) of erucic acid chain, the total amount of oleic acid and linoleic acid were negatively correlated with the sowing date; the UFA content, the unsatu- ration index, the SFA content, the 18-C FA content, and the ratio of UFA to FA in erucic acid chain were positively correlated with the sowing date. The contents of erucic acid, thioglycoside, seed protein, oleic acid, linolenic acid and eicosenoic acid were negatively correlated with the plant density, while the contents of oil, palmitic acid, stearic acid and linoleic acid were positively correlated with the plant density. The total amount of fat and protein (F & P), and the ratio of UFA to FA in erucic acid chain were negatively correlated with the plant density, while the UFA content, the unsaturation index, the SFA content, the ratio of UFA to SFA, the 18-C FA content, the FA in erucic acid chain, and the total amount of oleic acid and linoleic acid were positively correlated with the plant density. The contents of erucic acid, thioglycoside, oil, protein in milled rapeseed, palmitic acid and eicosenoic acid were negatively correlated with the nitrogen fertilizer amount, while the contents of seed protein, oleic acid, stearic acid, linoleic acid and linolenic acid were posi- tively correlated with the nitrogen fertilizer amount; the total F & P, the unsaturation index and the ratio of UFA to FA in erucic acid chain were positively correlated with the nitrogen fertilizer amount, while the UFA content, the SFA content, the FA in erucic acid chain, the total amount of oleic acid and linoleic acid, the ratio of UFA to SFA, and the 18-C FA content were negatively correlated with the nitrogen fertilizer amount The contents of erucic acid, thioglycoside, seed protein, linoleic acid and linolenic acid were negatively correlated with the potash fertilizer amount, while contents of oil, oleic acid, stearic acid and eicosenoic acid were positively correlated with the potash fertilizer amount; the total F & P, the unsaturation index, the SFA, and the ratio of UFA to FA in erucic acid chain were negatively correlated with the potash fertilizer amount There were negative correlations between the contents of erucic acid, thioglycoside, seed protein, palmitic acid, stearic acid, linoleic acid, linolenic acid and phosphate fertilizer amount; positive correlations between the contents of oil, oleic acid, eicosenoic acid and phosphate fertilizer amount The total UFA, the unsaturation index, the 1843 FA, the SFA, the FA in erucic acid chain, and the ratio of UFA to FA in erucic acid chain were negatively correlated with the phosphate fertilizer amount [Conclusion] This study identified the correlations of the five cultivation factors with the quality parameters of high-quality Brassica napus hybrids, to provide theoretical basis for its cultivation. 展开更多
关键词 Cultivation factors quality traits quality combination traits Influence
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Effect of geometrical parameters on forming quality of high-strength TA18 titanium alloy tube in numerical control bending 被引量:7
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作者 方军 梁闯 +1 位作者 鲁世强 王克鲁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期309-318,共10页
The forming quality of high-strength TA18 titanium alloy tube during numerical control bending in changing bending angle β, relative bending radius R/D and tube sizes such as diameter D and wall thickness t was clari... The forming quality of high-strength TA18 titanium alloy tube during numerical control bending in changing bending angle β, relative bending radius R/D and tube sizes such as diameter D and wall thickness t was clarified by finite element simulation. The results show that the distribution of wall thickness change ratio Δt and cross section deformation ratio ΔD are very similar under different β; the Δt and ΔD decrease with the increase of R/D, and to obtain the qualified bent tube, the R/D must be greater than 2.0; the wall thinning ratio Δto slightly increases with larger D and t, while the wall thickening ratio Δti and ΔD increase with the larger D and smaller t; the Δto and ΔD firstly decrease and then increase, while the Δti increases, for the same D/t with the increase of D and t. 展开更多
关键词 high-strength TA18 tube geometrical parameters forming quality finite element simulation numerical control bending
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Effect of Cultivation Conditionss on Quality Parameters of High Grade Hybrid Rape of Brassica napus L.
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作者 赵继献 任廷波 程国平 《Agricultural Science & Technology》 CAS 2013年第1期59-68,共10页
[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapesee... [Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed. 展开更多
关键词 Hybrid rapeseed Cultivation factor quality parameters Orthogonal rota- tion combination design EFFECT
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Comprehensive evaluation of water quality parameters in Tianjin Dagu Dainage Canal 被引量:1
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作者 董玉波 戴媛媛 +1 位作者 马超 孙学亮 《Marine Science Bulletin》 CAS 2014年第2期90-96,共7页
In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons... In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons in 2012 - 2013 are selected, and Water Quality Pollution Index (API) is applied to evaluate water quality indices, aiming for the systematic evaluation of the water quality of Dagu Dainage Canal. The results showed that four stations of D3, D6, D7and D9 for S2 had the type Ⅱand Ⅲ of water; others had the type Ⅰ ; the total level of TOC, TPH, Cu, Pb, Zn, Cd, Hg, As and Cr were type Ⅰ, Ⅳ, Ⅱ, Ⅴ, Ⅱ, Ⅴ, Ⅲ, Vand Ⅴ. Water Quality Pollution Index (API) was 3.28, which illustrated Dagu Dainage Canal was in the state of contamination and the degree of pollution exceeded the standard functional areas. 展开更多
关键词 Dagu Dainage Canal water quality indices spatial and temporadistribution comprehensive evaluation
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Structure Parameters and Physiological Indices Research of High-quality and High-yield Apple Orchards 被引量:1
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作者 薛晓敏 王翠玲 +2 位作者 王金政 孟海凤 聂佩显 《Agricultural Science & Technology》 CAS 2014年第11期1953-1956,1959,共5页
In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of ap... In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively. 展开更多
关键词 High-quality and high-yield Apple orchard Structure parameters Physio-logical index
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Does exposure to computers affect the routine parameters of semen quality? 被引量:6
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作者 Yue-Lian Sun Wei-Jin Zhou Jun-Qing Wu Er-Sheng Gao 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第3期263-266,共4页
Aim: To assess whether exposure to computers harms the semen quality of healthy young men. Methods: A total of 178 subjects were recruited from two maternity and children healthcare centers in Shanghai, 91 with a hi... Aim: To assess whether exposure to computers harms the semen quality of healthy young men. Methods: A total of 178 subjects were recruited from two maternity and children healthcare centers in Shanghai, 91 with a history of exposure to computers (i.e., exposure for 20 h or more per week in the last 2 years) and 87 persons to act as control (no or little exposure to computers). Data on the history of exposure to computers and other characteristics were obtained by means of a structured questionnaire interview. Semen samples were collected by masturbation in the place where the semen samples were analyzed. Results: No differences in the distribution of the semen parameters (semen volume, sperm density, percentage of progressive sperm, sperm viability and percentage of normal form sperm) were found between the exposed group and the control group. Exposure to computers was not found to be a risk factor for inferior semen quality after adjusting for potential confounders, including abstinence days, testicle size, occupation, history of exposure to toxic substances. Conclusion: The present study did not find that healthy: men exposed to computers had inferior semen quality. (Asian J Andro12005 Sep; 7: 263-266) 展开更多
关键词 COMPUTER MAGNETIZATION electromagnetization male reproduction semen analysis semen quality semen parameters
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Analysis of acquisition parameters and geometry quality 被引量:2
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作者 Zhao Hu Xu Hao +2 位作者 Di Zhi-Xin Zhang Jin-Miao Liu Zhi-Peng 《Applied Geophysics》 SCIE CSCD 2018年第3期413-419,共7页
High-quality seismic geometry is the key to obtain high-quality seismic data, and can affect the accuracy of data processing and imaging. Based on the analysis of the relationship between the quality of the geometry a... High-quality seismic geometry is the key to obtain high-quality seismic data, and can affect the accuracy of data processing and imaging. Based on the analysis of the relationship between the quality of the geometry and the four acquisition parameters(the number of traces, shot line spacing, and the space and number of receiver lines), a quality evaluation method of the geometry based on comprehensive quality factor(CQF) is proposed, and the relationship between the geometry quality and the four parameters is given. We use field data collected in an oil field in Western China with complex geology: First we use a wide azimuth geometry. Then, we calculate the relationship curve between geometry and data quality by varying each parameter while keeping the rest fixed. and the analysis results are given by using the CQF evaluation method. The results show that the shot-line spacing has the greatest effect on the quality of the geometry, and the increase of the receiver line spacing can appropriately improve the quality of the geometry, and the increase of the number of receiving traces can improve the geometry quality. The different acquisition parameters have different effects on the imaging quality of shallow and deep events. The model forward and prestack depth migration are used to generate prestack depth migration profiles with different acquisition parameters. The imaging results are consistent with the above calculated results. According to the depth of the target layer, the quality factor evaluation method is applied to guide the design of the geometry and optimize the acquisition parameters to improve the imaging accuracy of seismic data. 展开更多
关键词 SEISMIC ACQUISITION GEOMETRY quality FACTOR ACQUISITION parameters
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Influence of FSW parameters on formation quality and mechanical properties of Al 2024-T351 butt welded joints 被引量:8
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作者 I.RADISAVLJEVIC A.ZIVKOVIC +1 位作者 N.RADOVIC V.GRABULOV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3525-3539,共15页
The influence of R/v ratio on joint quality in 2024-T351 aluminum alloy was studied. Specimens were subjected to friction stir welding with the rotation rates of 750, 950 and 1180 r/min and welding speed between 73 an... The influence of R/v ratio on joint quality in 2024-T351 aluminum alloy was studied. Specimens were subjected to friction stir welding with the rotation rates of 750, 950 and 1180 r/min and welding speed between 73 and 190 mm/min, providing R/v ratio between 5.00 and 10.27. The welded joints were tested by means of both non-destructive (visual, penetrant and X-ray inspection) and destructive (metallographic, tension and hardness) testing. In all specimens typical zones are revealed, with corresponding differences in grain size. Tensile efficiency of the joints obtained is in the range of 52.2%to 82.3%. The results show that the best quality is obtained at R/v ratio of 8.06, 10.17 and 10.27. This behavior is attributed to the assumption that the material flows around the pin with an optimal speed, i.e. sufficient amount of material is available to fill the gap and prevent tunnel formation. R/v ratio also showed influence on hardness distribution, onion features and crack initiation/propagation zones. 展开更多
关键词 Al 2024 alloy friction stir welding welding parameters heat input weld quality
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Identification welding parameters using complex criteria of quality 被引量:3
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作者 Aleksandr Sergeevich Babkin Chang Yunlong Igor Aleksandrovich Babkin 《China Welding》 EI CAS 2017年第4期1-9,共9页
In the present paper,the graphical method determination of optimal welding parameters of GMAW is described.Some quality complex criteria that are the ratio of weld sizes have been proposed. These criteria allow optimi... In the present paper,the graphical method determination of optimal welding parameters of GMAW is described.Some quality complex criteria that are the ratio of weld sizes have been proposed. These criteria allow optimizing the shape of the weld metal zone,reducing the likelihood of hot cracks formation,and reducing the stress concentration of the weld at the toe. In the proposed methodology,the earlier described equations connecting the welding parameters and the weld dimensions of mild and low-alloy steels are explored. Determination of the optimal welding parameters is carried out graphically taking into account the variance of the welding parameters. An example of using the proposed method destined to determine the optimum welding parameters is provided. It is shown that its accuracy is sufficiently good for a practical application. 展开更多
关键词 gas metal ARC WELDING INVERSE problem quality CRITERIA optimal WELDING parameters WELD dimensions
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Modeling river water quality parameters using modified adaptive neuro fuzzy inference system 被引量:2
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作者 Armin Azad Hojat Karami +2 位作者 Saeed Farzin Sayed-Farhad Mousavi Ozgur Kisi 《Water Science and Engineering》 EI CAS CSCD 2019年第1期45-54,共10页
Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improv... Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improving the performance of artificial intelligence models such as the adaptive neuro fuzzy inference system (ANFIS) and artificial neural networks (ANN). Attempts have been made to make the models more suitable and accurate with the replacement of other training methods that do not suffer from some shortcomings, including a tendency to being trapped in local optima or voluminous computations. This study investigated the applicability of ANFIS with particle swarm optimization (PSO) and ant colony optimization for continuous domains (ACOR) in estimating water quality parameters at three stations along the Zayandehrood River, in Iran. The ANFIS-PSO and ANFIS-ACOR methods were also compared with the classic ANFIS method, which uses least squares and gradient descent as training algorithms. The estimated water quality parameters in this study were electrical conductivity (EC), total dissolved solids (TDS), the sodium adsorption ratio (SAR), carbonate hardness (CH), and total hardness (TH). Correlation analysis was performed using SPSS software to determine the optimal inputs to the models. The analysis showed that ANFIS-PSO was the better model compared with ANFIS-ACOR. It is noteworthy that EA models can improve ANFIS' performance at all three stations for different water quality parameters. 展开更多
关键词 Water quality parameters ANFIS Evolutionary algorithm Particle SWARM OPTIMIZATION Ant COLONY OPTIMIZATION for continuous DOMAINS
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Reproducibility of optical quality parameters measured at objective and subjective best focuses in a doublepass system 被引量:8
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作者 Ai-Lian Hu Li-Ya Qiao +3 位作者 Ye Zhang Xiao-Gu Cai Lei Li Xiu-Hua Wan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第5期1043-1050,共8页
AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.METHODSThirty Chinese healthy adults (19 to 40 yea... AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.METHODSThirty Chinese healthy adults (19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System (OQAS) with an artificial pupil diameter of 4.0 mm.RESULTSWith each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency (MTF<sub>cutoff</sub>), the Strehl<sup>2D</sup> ratio, the OQAS values (OVs) at contrasts of 100%, 20%, 9% and the objective scatter index (OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit (RL) and the coefficient of repeatability (COR). Reproducibility of the two methods was evaluated by intra-class correlation coefficient (ICC) and the 95% limits of agreement (Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs (percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13% and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83% and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters (in comparison of the two methods) ranged from -0.57 to 42.18 (MTF<sub>cutoff</sub>), -0.01 to 0.23 (Strehl<sup>2D</sup> ratio), -0.02 to 1.40 (OV<sub>100%</sub>), -0.10 to 1.75 (OV<sub>20%</sub>), -0.14 to 1.80 (OV<sub>9%</sub>) and -1.46 to 0.18 (OSI).CONCLUSIONMeasurements provided by OQAS with either method showed a good repeatability. However, the results obtained from the two different measurement methods showed a poor reproducibility. These findings suggest that it might be best to evaluate patients' optical quality by OQAS using the best focus as chosen automatically by the instrument. 展开更多
关键词 optical quality double-pass system best focus REPEATABILITY REPRODUCIBILITY
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Understanding Seasonal and Spatial Variation of Water Quality Parameters in Mangrove Estuary of the Nyong River Using Multivariate Analysis (Cameroon Southern Atlantic Coast) 被引量:1
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作者 Anselme Crépin Mama Willy Karol Abouga Bodo +2 位作者 Gisele Flodore Youbouni Ghepdeu Gordon Nwutih Ajonina Jules Rémi Ngoupayou Ndam 《Open Journal of Marine Science》 2021年第3期103-128,共26页
To evaluate the actual status of water quality and conclude on the mains source of pollution in the Nyong estuary River, seasonal and spatial variation of water quality parameters was interpreted by multivariate stati... To evaluate the actual status of water quality and conclude on the mains source of pollution in the Nyong estuary River, seasonal and spatial variation of water quality parameters was interpreted by multivariate statistical techniques (Principal Component analysis). Nine (09) environmental variables were monitored at four surface stations in the estuary for two seasonal cycles. The fieldwork was conducted from 2018 to 2019 during high tide and low <span style="letter-spacing:0.1pt;">tide for each survey. In situ physical parameters were measured for a total of</span> 64 samples (32 samples for each tide). The laboratory works consisted of some physicochemical analyses and processing of these data by descriptive <span style="letter-spacing:0.1pt;">and multidimensional statistical analyses. Temperature, suspended particle</span> matter, nitrate, nitrite and phosphate change significantly in the estuary with season (<i>p</i> < 0.05), while salinity, dissolved oxygen, pH, and ammonium do not vary significantly with season (<i>p</i> > 0.05). Principal Component analysis found temperature, salinity, pH, ammonium to be the most important parameters contributing to the fluctuations of surface water quality in the Nyong estuary during the dry seasons whereas suspended particle matter, nitrate, and phosphate are the most important parameters contributing to the fluctuation of surface water quality in the Nyong estuary during the rainy seasons. Based on spatial variation, the Principal Component analysis found that, suspended particle matter, nitrate and phosphate contribute to the fluctuation of surface water quality parameters upstream of the estuary while downstream salinity, pH, and ammonium contribute the most to the fluctuation of surface water quality. This study shows us the usefulness of multivariate statistical techniques used in assessing water quality data sets that would help us in un<span style="letter-spacing:0.1pt;">derstanding seasonal and spatial variations of water quality parameters to</span> manage estuarine systems. 展开更多
关键词 Water quality parameters Nyong Estuary Principal Component Analysis
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Effect of HMW-GS 5+10 on Quality Parameters in Four Leading Wheat Cultivars 被引量:7
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作者 ZHANG Yan-bin, SUN Lian-fa, XIN Wen-li, SONG Qin-jie, ZHANG Chun-li, ZHAO Hai-bin, XIAO Zhi-min and QI Shi-yuCrop Breeding Institute , Heilongjiang Academy of Agricultural Sciences , Harbin 150086 , P. R. China 《Agricultural Sciences in China》 CAS CSCD 2003年第5期483-488,共6页
HMW-GS 5 + 10 was introduced to four major wheat cultivars Kehan9, Kefeng3, Longmai20 and Kenda4 through 5 or 6 consecutive backcrosses. No significant difference in protein content and dry gluten content was observed... HMW-GS 5 + 10 was introduced to four major wheat cultivars Kehan9, Kefeng3, Longmai20 and Kenda4 through 5 or 6 consecutive backcrosses. No significant difference in protein content and dry gluten content was observed between cultivars containing 5 + 10 and 2 + 12 or 3 + 12 (P>0.1). In cultivars containing HMW-GS 5 + 10, the ratio of wet gluten content to dry gluten content was 2. 9 - 5.0% (P<0. 01) lower than the ratio from the cultivars containing 2 + 12 or 3 + 12, the ratio of Zeleny sedimentation volume to dry gluten content was 4. 5 - 13. 4% (P<0.05) higher. The degree of softening in cultivars having 5 + 10 was 15 -25 FU (P<0. 01) lower, while the maximum resistance was 82 - 193 EU (P<0. 05) higher. Backcrosses with biochemical marker assisted selection in the improvement of quality in wheat cultivars was discussed. 展开更多
关键词 WHEAT HMW glutenin subunits Selective backcross quality
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Predictive Model for Cement Clinker Quality Parameters 被引量:1
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作者 Nsidibe-Obong Ekpe Moses Sunday Boladale Alabi 《Journal of Materials Science and Chemical Engineering》 2016年第7期84-100,共17页
Managers of cement plants are gradually becoming aware of the need for soft sensors in product quality assessment. Cement clinker quality parameters are mostly measured by offline laboratory analysis or by the use of ... Managers of cement plants are gradually becoming aware of the need for soft sensors in product quality assessment. Cement clinker quality parameters are mostly measured by offline laboratory analysis or by the use of online analyzers. The measurement delay and cost, associated with these methods, are a concern in the cement industry. In this study, a regression-based model was developed to predict the clinker quality parameters as a function of the raw meal quality and the kiln operating variables. This model has mean squared error, coefficient of determination, worst case relative error and variance account for (in external data) given as 8.96 × 10<sup>–7</sup>, 0.9999, 2.17% and above 97%, respectively. Thus, it is concluded that the developed model can provide real time estimates of the clinker quality parameters and capture wider ranges of real plant operating conditions from first principle-based cement rotary kiln models. Also, the model developed can be utilized online as soft sensor since they contain only variables that are easily measured online. 展开更多
关键词 Clinker quality parameters Online Estimation Cement Rotary Kiln MODEL Soft Sensor
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