Microplastics often co-occur with a variety of organic contaminants in aquatic environment and pose combined risks to aquatic wildlife. Here, we investigated joint effects of microsized polystyrene(mPS, 5 μm) and an ...Microplastics often co-occur with a variety of organic contaminants in aquatic environment and pose combined risks to aquatic wildlife. Here, we investigated joint effects of microsized polystyrene(mPS, 5 μm) and an organophosphate pesticide chlorpyrifos on zebrafish,using multiple endpoints at both fish individual and gut microbiota levels. It was revealed that mPS ingested by zebrafish accumulated in gut and liver, and caused oxidative stress, hyperactive swimming performance and histological damages in fish, and induced disorders and diversity alterations of the gut microbial community. More importantly, mPS exhibited considerable adsorption capacity against chlorpyrifos, and those adsorbing chlorpyrifos presented greater effects on fish individuals but no different effects on gut microbiota compared to single mPS exposure. Together with body residues of chlorpyrifos in zebrafish,it was proposed that the joint effects between mPS and chlorpyrifos were attributed to the chlorpyrifos released from mPS within zebrafish. The present results provided a comprehensive understanding of joint effects of mPS and contaminants co-occurring in the environment and emphasized the importance of considering the adsorbed chemicals in toxicological studies of microplastics.展开更多
BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hyd...BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hydroxyvitamin D[25(OH)D]concentrations(a marker of vitamin D level)and MetS have a long-term impact on the risk of CVD and all-cause mortality,and individuals with vitamin D deficiency can be identified by multiple factors.METHODS A sample of 9094 adults,20 to 90 years of age,who participated in the Third National Health and Nutrition Examination Survey(NHANES III,1988 to 1994)were followed through December 2015 was analyzed.The associations of serum 25(OH)D concentrations and MetS with CVD and all-cause mortality were analyzed longitudinally using Cox regression models.Classification and regression tree(CART)for machine learning was applied to classify individuals with vitamin D deficiency.RESULTS Of 9094 participants,30%had serum 25(OH)D concentrations<20 ng/mL(defined as vitamin D deficiency),39%had serum 25(OH)D concentrations between 20 to 29 ng/mL(insufficiency),and 31%had serum 25(OH)D concentrations≥30 ng/mL(sufficiency).Prevalence of MetS was 28.4%.During a mean of 18 years follow-up,vitamin D deficiency and MetS were significantly associated with increased risk of CVD and all-cause mortality.Subjects with both vitamin D deficiency and MetS had the highest risk of CVD mortality(HR=1.77,95%CI:1.22-2.58)and all-cause mortality(HR=1.62,95%CI:1.26-2.09),followed by those with both vitamin D insufficiency and MetS for CVD mortality(HR=1.59,95%CI:1.12-2.24),and all-cause mortality(HR=1.41,95%CI:1.08-1.85).Meanwhile,vitamin D sufficiency significantly decreased the risk of CVD and all-cause mortality for those who even had MetS.Among the total study sample,CART analysis suggests that being non-Hispanic Black,having lower serum folate level,and being female were the first three predictors for those with serum 25(OH)D deficiency.CONCLUSION Vitamin D deficiency and MetS were significantly associated with increased risk of CVD and allcause mortality.There was a significant joint effect of vitamin D deficiency and MetS on the risk of mortality.Findings of the CART analysis may be useful to identify individuals positioned to benefit from interventions to reduce the risk of CVD and all-cause mortality.展开更多
This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays a...This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays an important role in the vascular relaxation, neurotransmission and immune system functioning. Analyses performed by EPR spectroscopy revealed Hem-NO complex signals from paramagnetic centers in arbitrary units;produced nitrogen oxide amount in liver tissues was determined by method of double integration signals from nitrosyl complexes.展开更多
The combined and interactive effects of the bolt-hole fit conditions and the preloads of the fasteners on the load carrying capacity of single-lap composite-to-titanium bolted joints have been investigated both experi...The combined and interactive effects of the bolt-hole fit conditions and the preloads of the fasteners on the load carrying capacity of single-lap composite-to-titanium bolted joints have been investigated both experimentally and numerically. Quasi-static tests of the hybrid joints with different fit conditions are implemented, and a three dimensional finite element progressive failure analysis model is proposed to predict the influences of the bolt-hole fit conditions and fastener＇s pre- loads on the mechanical behaviors of the joints. Based on the experimental validated simulation method, a multi-factor, mixed levels orthogonal design table and the analysis of variance method are used to arrange the simulation conditions and to further study the interactive effects of preloads and fit conditions. Through the analysis of the results, for the researched double bolt, single-lap composite-titanium joints, it is found that： the effects of both the interference fit and the preloads change from positive into negative mode with the increase of the interference fit values or preload values; appropriate bolt-hole fit conditions and preloads can improve the bolt-hole contact conditions of the loaded joints, and then retard the fiber failures around the fastener holes, and increase the load carrying capacity of the joints eventually; the interactive effect of the bolt-hole interference fit conditions and preloads cannot be ignored and the parameters need to be considered together and synthetically as the joints are being optimized.展开更多
In order to evaluate ecological risk of agrochemicals in common use, joint toxic effects of acetochlor and urea on germinating characteristics of Chinese cabbage (Brassica Pe-kinensis Rupr) seeds were investigated usi...In order to evaluate ecological risk of agrochemicals in common use, joint toxic effects of acetochlor and urea on germinating characteristics of Chinese cabbage (Brassica Pe-kinensis Rupr) seeds were investigated using the water-culture method and the soil-culture method. The results indicated(that excessive application of acetochlor and urea, when the concentrations were higher than 31.3 mg · kg-1 for acetochlor and 500 mg · kg-1 for urea, had strong inhibitory effects on the rate of seed germination, root elongation and hypocotyl length of Chinese cabbage. The inhibitory rate of the germinating characteristics of Chinese cabbage seeds was significantly increased with an increase in the concentration of acetochlor or urea. The two agrochemicals in water had a stronger toxicity than these in the soil at the same concentration. Among the three indexes, hypocotyl length was the most sensitive to the toxicity of acetochlor and urea.展开更多
In this study, the joint effects of Cd(Ⅱ), Pb(Ⅱ) and atrazine (ATR) on Solidago Canadensis L. were investigated. The results showed that soil containing Cd, Pb and ATR could inhibit root elongation of Solidago Canad...In this study, the joint effects of Cd(Ⅱ), Pb(Ⅱ) and atrazine (ATR) on Solidago Canadensis L. were investigated. The results showed that soil containing Cd, Pb and ATR could inhibit root elongation of Solidago Canadensis L., and that there was a positive linear relationship between the inhibitory rate of root elongation and the concentrations of Pb(Ⅱ). The mixture of Cd(Ⅱ) and Pb(Ⅱ)-ATR in soil showed a significant adverse effect on root and shoot biomass of Solidago Canadensis L. Acetylsalicylic acid (ASA) contents increased slightly at the lower concentrations of Cd(Ⅱ)-ATR, then decreased when Cd(Ⅱ)-ATR concentrations were higher than those of 1.0 TUmix(Cd+ATR). The toxic effect of Pb(Ⅱ)-ATR on the ASA contents of Solidago Canadensis L. was greater than that of Cd(Ⅱ)-ATR. Soluble sugar contents firstly decreased and then increased with increasing concentrations of Cd(Ⅱ)-ATR and displayed fluctuation with increasing concentrations of Pb(Ⅱ)-ATR. Total protein contents in-creased with increasing concentrations of Cd(Ⅱ) and Pb(Ⅱ)-ATR , relative to the control sample. The NP-SH con-tents showed a significant increase up to 12.2 mg/gfw of Cd(Ⅱ)-ATR, followed by a significant decline to 4.5 mg/gfw after 14 days of exposure. The effect of Pb(Ⅱ)-ATR was similar to that of Cd(Ⅱ)-ATR but the amount of NP-SH was not higher than that of Cd(Ⅱ)-ATR.展开更多
Three-dimensional thermo-electrical finite element analyses were conducted to simulate the current density and temperature distributions in solder bump joints with different pad geometries.The effects of pad thickness...Three-dimensional thermo-electrical finite element analyses were conducted to simulate the current density and temperature distributions in solder bump joints with different pad geometries.The effects of pad thickness,diameter and shape on current density and temperate distributions were investigated respectively.It was found that pads with larger thickness or/and diameter could reduce current density and temperature in solder bump significantly.Pad shapes affected the current density and temperature distributions in solder bumps.The relatively low current density and temperature didn＇t occur in the bump joint with traditional rounded pad but occurred in bump joints with octagonal and nonagonal pads respectively.Therefore,optimized pad geometry may be designed to alleviate the current crowding effect and reduce the bump temperature,and therefore delay electromigration failure and increase the mean-time-to-failure.展开更多
Based on the survey research of poverty controlling model of "Three Drives, Four Joints" in Zhen'an County, its forming motives, implementing mechanism, and constraint factors have been explored to testi...Based on the survey research of poverty controlling model of "Three Drives, Four Joints" in Zhen'an County, its forming motives, implementing mechanism, and constraint factors have been explored to testify its enlightenment and applicability, establishing a promotable, applicable, and effective poverty alleviation model. "Three Drives, Four Joints" model is linked to the poor who lacks ability of self-development. Relying on the drives from key leading companies, the capable and the rich, a community with shared interests by the poor and the subjects of the "three drives" could be formed through "Joint Production, Joint Resources, Joint Community of Stock, and Joint Operation". The linked poverty alleviation development model of "the influential and the rich bring along the poor" and "A rich household would help the others" come into being. It is found out that the model of "Three Drives, Four Joints" is in essence a poverty alleviation method focusing on the increase of the income and diversified ways of increasing the earnings. Problems of poverty alleviation carrier and joint mechanism have been solved in the poverty alleviation process. The model is innovative in activating the resource elements, helping to move the poor out of poverty. A referential, copyable, and applicable model is offered to advance the poverty alleviation in mountainous areas in China.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 21936004, 21806055)the Joint Funds of the National Natural Science Foundation of China (No. U1901220)+2 种基金the Guangdong Provincial Department of Science and Technology (No. 2019A1515011583)Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (No. SML2021SP208)Innovative Research Team of Department of Education of Guangdong Province (No. 2020KCXTD005)。
文摘Microplastics often co-occur with a variety of organic contaminants in aquatic environment and pose combined risks to aquatic wildlife. Here, we investigated joint effects of microsized polystyrene(mPS, 5 μm) and an organophosphate pesticide chlorpyrifos on zebrafish,using multiple endpoints at both fish individual and gut microbiota levels. It was revealed that mPS ingested by zebrafish accumulated in gut and liver, and caused oxidative stress, hyperactive swimming performance and histological damages in fish, and induced disorders and diversity alterations of the gut microbial community. More importantly, mPS exhibited considerable adsorption capacity against chlorpyrifos, and those adsorbing chlorpyrifos presented greater effects on fish individuals but no different effects on gut microbiota compared to single mPS exposure. Together with body residues of chlorpyrifos in zebrafish,it was proposed that the joint effects between mPS and chlorpyrifos were attributed to the chlorpyrifos released from mPS within zebrafish. The present results provided a comprehensive understanding of joint effects of mPS and contaminants co-occurring in the environment and emphasized the importance of considering the adsorbed chemicals in toxicological studies of microplastics.
文摘BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hydroxyvitamin D[25(OH)D]concentrations(a marker of vitamin D level)and MetS have a long-term impact on the risk of CVD and all-cause mortality,and individuals with vitamin D deficiency can be identified by multiple factors.METHODS A sample of 9094 adults,20 to 90 years of age,who participated in the Third National Health and Nutrition Examination Survey(NHANES III,1988 to 1994)were followed through December 2015 was analyzed.The associations of serum 25(OH)D concentrations and MetS with CVD and all-cause mortality were analyzed longitudinally using Cox regression models.Classification and regression tree(CART)for machine learning was applied to classify individuals with vitamin D deficiency.RESULTS Of 9094 participants,30%had serum 25(OH)D concentrations<20 ng/mL(defined as vitamin D deficiency),39%had serum 25(OH)D concentrations between 20 to 29 ng/mL(insufficiency),and 31%had serum 25(OH)D concentrations≥30 ng/mL(sufficiency).Prevalence of MetS was 28.4%.During a mean of 18 years follow-up,vitamin D deficiency and MetS were significantly associated with increased risk of CVD and all-cause mortality.Subjects with both vitamin D deficiency and MetS had the highest risk of CVD mortality(HR=1.77,95%CI:1.22-2.58)and all-cause mortality(HR=1.62,95%CI:1.26-2.09),followed by those with both vitamin D insufficiency and MetS for CVD mortality(HR=1.59,95%CI:1.12-2.24),and all-cause mortality(HR=1.41,95%CI:1.08-1.85).Meanwhile,vitamin D sufficiency significantly decreased the risk of CVD and all-cause mortality for those who even had MetS.Among the total study sample,CART analysis suggests that being non-Hispanic Black,having lower serum folate level,and being female were the first three predictors for those with serum 25(OH)D deficiency.CONCLUSION Vitamin D deficiency and MetS were significantly associated with increased risk of CVD and allcause mortality.There was a significant joint effect of vitamin D deficiency and MetS on the risk of mortality.Findings of the CART analysis may be useful to identify individuals positioned to benefit from interventions to reduce the risk of CVD and all-cause mortality.
文摘This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays an important role in the vascular relaxation, neurotransmission and immune system functioning. Analyses performed by EPR spectroscopy revealed Hem-NO complex signals from paramagnetic centers in arbitrary units;produced nitrogen oxide amount in liver tissues was determined by method of double integration signals from nitrosyl complexes.
文摘The combined and interactive effects of the bolt-hole fit conditions and the preloads of the fasteners on the load carrying capacity of single-lap composite-to-titanium bolted joints have been investigated both experimentally and numerically. Quasi-static tests of the hybrid joints with different fit conditions are implemented, and a three dimensional finite element progressive failure analysis model is proposed to predict the influences of the bolt-hole fit conditions and fastener＇s pre- loads on the mechanical behaviors of the joints. Based on the experimental validated simulation method, a multi-factor, mixed levels orthogonal design table and the analysis of variance method are used to arrange the simulation conditions and to further study the interactive effects of preloads and fit conditions. Through the analysis of the results, for the researched double bolt, single-lap composite-titanium joints, it is found that： the effects of both the interference fit and the preloads change from positive into negative mode with the increase of the interference fit values or preload values; appropriate bolt-hole fit conditions and preloads can improve the bolt-hole contact conditions of the loaded joints, and then retard the fiber failures around the fastener holes, and increase the load carrying capacity of the joints eventually; the interactive effect of the bolt-hole interference fit conditions and preloads cannot be ignored and the parameters need to be considered together and synthetically as the joints are being optimized.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 20225722) for distinguished young scholarsa component part of 973 Project (approved No.2004CB418503) supported by the Ministry of Science and Technology,People's Republic of China.
文摘In order to evaluate ecological risk of agrochemicals in common use, joint toxic effects of acetochlor and urea on germinating characteristics of Chinese cabbage (Brassica Pe-kinensis Rupr) seeds were investigated using the water-culture method and the soil-culture method. The results indicated(that excessive application of acetochlor and urea, when the concentrations were higher than 31.3 mg · kg-1 for acetochlor and 500 mg · kg-1 for urea, had strong inhibitory effects on the rate of seed germination, root elongation and hypocotyl length of Chinese cabbage. The inhibitory rate of the germinating characteristics of Chinese cabbage seeds was significantly increased with an increase in the concentration of acetochlor or urea. The two agrochemicals in water had a stronger toxicity than these in the soil at the same concentration. Among the three indexes, hypocotyl length was the most sensitive to the toxicity of acetochlor and urea.
基金supported by the Foundation of Chongqing Key Laboratory of Micro/Nano Materials Engineering and Technology (No.KFJJ1106)Foundation of Jiangsu Marine Resources Development Research Institute (No.JSIMR10E04)+1 种基金Foundation of Jiangsu university student renovation project of institution of higher education (No.1116)the National Nature Science Foundation of China (Project No.20977040)
文摘In this study, the joint effects of Cd(Ⅱ), Pb(Ⅱ) and atrazine (ATR) on Solidago Canadensis L. were investigated. The results showed that soil containing Cd, Pb and ATR could inhibit root elongation of Solidago Canadensis L., and that there was a positive linear relationship between the inhibitory rate of root elongation and the concentrations of Pb(Ⅱ). The mixture of Cd(Ⅱ) and Pb(Ⅱ)-ATR in soil showed a significant adverse effect on root and shoot biomass of Solidago Canadensis L. Acetylsalicylic acid (ASA) contents increased slightly at the lower concentrations of Cd(Ⅱ)-ATR, then decreased when Cd(Ⅱ)-ATR concentrations were higher than those of 1.0 TUmix(Cd+ATR). The toxic effect of Pb(Ⅱ)-ATR on the ASA contents of Solidago Canadensis L. was greater than that of Cd(Ⅱ)-ATR. Soluble sugar contents firstly decreased and then increased with increasing concentrations of Cd(Ⅱ)-ATR and displayed fluctuation with increasing concentrations of Pb(Ⅱ)-ATR. Total protein contents in-creased with increasing concentrations of Cd(Ⅱ) and Pb(Ⅱ)-ATR , relative to the control sample. The NP-SH con-tents showed a significant increase up to 12.2 mg/gfw of Cd(Ⅱ)-ATR, followed by a significant decline to 4.5 mg/gfw after 14 days of exposure. The effect of Pb(Ⅱ)-ATR was similar to that of Cd(Ⅱ)-ATR but the amount of NP-SH was not higher than that of Cd(Ⅱ)-ATR.
文摘Three-dimensional thermo-electrical finite element analyses were conducted to simulate the current density and temperature distributions in solder bump joints with different pad geometries.The effects of pad thickness,diameter and shape on current density and temperate distributions were investigated respectively.It was found that pads with larger thickness or/and diameter could reduce current density and temperature in solder bump significantly.Pad shapes affected the current density and temperature distributions in solder bumps.The relatively low current density and temperature didn＇t occur in the bump joint with traditional rounded pad but occurred in bump joints with octagonal and nonagonal pads respectively.Therefore,optimized pad geometry may be designed to alleviate the current crowding effect and reduce the bump temperature,and therefore delay electromigration failure and increase the mean-time-to-failure.
基金supported by National Natural Science Funds for Distinguished Young Scholar (Grant No. 71503202)the Fundamental Research Funds for the Central Universities (Grant No. 2017RWYB14)
文摘Based on the survey research of poverty controlling model of "Three Drives, Four Joints" in Zhen'an County, its forming motives, implementing mechanism, and constraint factors have been explored to testify its enlightenment and applicability, establishing a promotable, applicable, and effective poverty alleviation model. "Three Drives, Four Joints" model is linked to the poor who lacks ability of self-development. Relying on the drives from key leading companies, the capable and the rich, a community with shared interests by the poor and the subjects of the "three drives" could be formed through "Joint Production, Joint Resources, Joint Community of Stock, and Joint Operation". The linked poverty alleviation development model of "the influential and the rich bring along the poor" and "A rich household would help the others" come into being. It is found out that the model of "Three Drives, Four Joints" is in essence a poverty alleviation method focusing on the increase of the income and diversified ways of increasing the earnings. Problems of poverty alleviation carrier and joint mechanism have been solved in the poverty alleviation process. The model is innovative in activating the resource elements, helping to move the poor out of poverty. A referential, copyable, and applicable model is offered to advance the poverty alleviation in mountainous areas in China.
