Joint Effects of Mexidol and Nitroglycerine on Nitric Oxide Formation in Animal Liver Tissues

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.

Joint effects of micro-sized polystyrene and chlorpyrifos on zebrafish based on multiple endpoints and gut microbial effects

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.

Single and joint stress of acetochlor and Pb on three agricultural crops in northeast China

In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seeds of the three crops including wheat （Triticum aestivum）, Chinese cabbage （Brassica pekimensis） and soybean （Glycine max） as the main crops in northeast China were exposed to acetochior as a herbicide and lead （Pb） as a heavy metal using the pot-culture method, and meadow brown soil as one of the main soils distributed in northeast China was applied in the investigation. The results indicated that the interactive effects of the two pollutants on root elongation of the three crops were very complicated although they had markedly significant （P〈0.01） linear interrelationships based on the regression analyses. When the concentration of added Pb^2＋ reached 200 mg/kg, acetochlor and Pb had an antagonistic effect on the inhibition of root elongation of the three crops. However, acetochlor and Pb had significantly （P〈0.05） synergic effects on the inhibition of root elongation when concentration of added Pb^2＋ was up to 1000 mg/kg. At the low concentration of added Pb, joint toxicity of acetochlor and Pb was more dependent on the concentration of Pb. Among the three crops, wheat was the most sensitive to the toxicity of Pb and Chinese cabbage was the most sensitive to the toxicity of acetochlor.

Shear strength criteria for rock,rock joints,rockfill and rock masses:Problems and some solutions

Although many intact rock types can be very strong,a critical confining pressure can eventually be reached in triaxial testing,such that the Mohr shear strength envelope becomes horizontal.This critical state has recently been better defined,and correct curvature or correct deviation from linear Mohr-Coulomb（MC） has finally been found.Standard shear testing procedures for rock joints,using multiple testing of the same sample,in case of insufficient samples,can be shown to exaggerate apparent cohesion.Even rough joints do not have any cohesion,but instead have very high friction angles at low stress,due to strong dilation.Rock masses,implying problems of large-scale interaction with engineering structures,may have both cohesive and frictional strength components.However,it is not correct to add these,following linear M-C or nonlinear Hoek-Brown（H-B） standard routines.Cohesion is broken at small strain,while friction is mobilized at larger strain and remains to the end of the shear deformation.The criterion ＇c then σn tan φ＇ should replace ＇c plus σn tan φ＇ for improved fit to reality.Transformation of principal stresses to a shear plane seems to ignore mobilized dilation,and caused great experimental difficulties until understood.There seems to be plenty of room for continued research,so that errors of judgement of the last 50 years can be corrected.

Vitamin d deficiency and metabolic syndrome:The joint effect on cardiovascular and all-cause mortality in the United States adults

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.

Effect of pad geometry on current density and temperature distributions in solder bump joints

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.

Effects of molten state of ultrasonic welded Joints of plastics on their strength

Effects of molten state of ultrasonic welded joints of plastics on their strength were investigated. Physical parameters such as temperature, viscosity and thickness of melting layers of plastic material joints were measured and analyzed. Results show that when the welding vibration amplitude and pressure increase, the temperature increases, the viscosity decreases, and the thickness of molten layer decreases. The microstructure of weld fusion zone was observed by using an optical microscope. It was found that there is strong orientation along transverse direction in the microstructure of fusion zone. Testing results show that the mechanics performance of welded joints are obviously anisotropic, and strongly affected by the thickness of molten layer and the extent of orientation.

Ecotoxicological effects of polycyclic musks and cadmium on seed germination and seedling growth of wheat(Triticum aestivum)

Single and joint toxic effects of polycyclic musks including 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2- benzopyran （HHCB） and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene （AHTN） and cadmium （Cd） on seed germination and seedling growth of wheat （Triticum aestivum） were investigated. The results showed that the toxicity sequence of HHCB toxic to wheat seed germination and seedling growth was similar to that of AHTN, that is, germination rate 〉 shoot elongation 〉 root elongation, while the toxicity of Cd was in the sequence of root elongation 〉 shoot elongation 〉 germination rate, according to the LC50 and EC50 values. It is suggested that polycyclic musks and Cd had different toxicological mechanisms. Root and shoot elongation of wheat might be good bioindicators for the contamination of polycyclic musks and Cd in soil. The mixture of polycyclic musks and Cd had synergistic effects on T. aestivum according to the equi-toxic mixture approach when root elongation was selected as the toxicological endpoint. Thus, the joint toxicity of HHCB and Cd was significantly higher than the single toxicity of HHCB or Cd, which was also confirmed by the EC50mix value of the mixture （EC50mix = 0.530 TUrnix）. The EC50mix value of the mixture of AHTN and Cd was 0.614 TUmix, which indicated that the mixture toxicity was strengthened when AHTN coexisted with Cd.

The toxic effects of three active pharmaceutical ingredients(APIs)with different efficacy to Vibrio fischeri

The environmental residues of active pharmaceutical ingredients(APIs)are associated with environmental risks and health problems,the influence to environment have become a matter of public concern.In this paper,the individual and joint toxicities to vibrio fischeri of three APIs,including ibuprofen,azithromycin,and triclosan were investigated.The EC50 endpoint values of the above tested APIs were 36.5×10^-5 mol L^-1,30.26×10^-5 mol L^-1,and 0.0155×10^-5 mol L^-1 respectively.It was indicated that the endpoint toxicities to vibrio fischeri for different mixtures are higher than those of the individual toxins.The joint toxicities of the multiple systems of three pharmaceuticals were evaluated by the additive index,toxicity unit,and mixed toxicity index methods.The consistent evaluation results were obtained.It was observed that antagonistic effects in binary and ternary systems were appeared different antagonistic strengths.It was deduced that different functional groups of the studied pharmaceuticals could affect the physiological and biochemical reaction processes of organisms.The obtained data of the acute toxicities of pharmaceuticals to vibrio fischeri can facilitate the evaluation of the environmental risks associated with emerging pollutants.

Joint model of user check-in activities for point-of-interest recommendation

With the rapid development of location-based networks, point-of-interest（POI） recommendation has become an important means to help people discover interesting and attractive locations, especially when users travel out of town. However, because users only check-in interaction is highly sparse, which creates a big challenge for POI recommendation. To tackle this challenge, we propose a joint probabilistic generative model called geographical temporal social content popularity（GTSCP） to imitate user check-in activities in a process of decision making, which effectively integrates the geographical influence, temporal effect, social correlation, content information and popularity impact factors to overcome the data sparsity, especially for out-of-town users. Our proposed the GTSCP supports two recommendation scenarios in a joint model, i.e., home-town recommendation and out-of-town recommendation. Experimental results show that GTSCP achieves significantly superior recommendation quality compared to other state-of-the-art POI recommendation techniques.

Human exposure to a mixture of endocrine disruptors and serum levels of thyroid hormones:A cross-sectional study

Exposure to endocrine disruptors(EDCs) could disrupt thyroid hormone homeostasis. However, human epidemiological studies reported inconsistent observations, and scarce information on the effect of a mixture of chemicals. The aim of the present study was to examine the associations of multiple chemicals with thyroid hormones among adults from China. We measured serum levels of thyroid hormones and urinary levels of 11 EDCs, including six phthalate metabolites, bisphenol A(BPA), bisphenol F(BPF), bisphenol S(BPS), perchlorate, and thiocyanate among 177 healthy adults without occupational exposure. Associations of multiple urinary analytes with serum thyroid hormones were examined by performing general linear regression analysis and bayesian kernal machine regression analysis. These EDCs were detected in almost all samples. After adjusting for various covariates, we observed only BPF significantly associated with total thyroxin(TT4)(β=-0.27, 95% confidence interval(CI) [-0.41,-0.14]), total triiodothyronine(TT3)(β=-0.02 95% CI [-0.03,-0.01]), free T4(fT4)(β=-0.02, 95% CI [-0.03,-0.01]), and free T3(fT3)(β=-0.04, 95% CI [-0.07,-0.01]), and mono-(2-ethyl-5-oxohexyl) phthalate(MEOHP) and monoethyl phthalate(MEP) positively associated with TT4(β=0.24, 95% CI [0.01, 0.48]) and fT4(β=0.02, 95% CI [0.01, 0.04]), respectively. Moreover, we observed significant dose-response relationships between TT4 and the mixture of11 EDCs, and BPF was the main contributor to the mixture effect, suggesting the priority of potential effect of BPF on disrupting thyroid function under a real scenario of human exposure to multiple EDCs. Our findings supported the hypothesis that human exposure to low levels of EDCs could alter thyroid hormones homeostasis among non-occupational healthy adults.

Response of antibiotic and heavy metal resistance genes to the co-occurrence of gadolinium and sulfamethoxazole in activated sludge systems

With the increasing use of antibiotics and rare earth elements(REE)during the coronavirus disease(COVID-19)pandemic,the co-occurrence of sulfamethoxazole(SMX)and gadolinium(Gd)has increased in wastewater treatment plants(WWTPs).However,the effects of SMX and Gd exposure on the transmission of antibiotic resistance genes(ARGs)and heavy metal resistance genes(MRGs)remain unknown.This study investigated the impacts of SMX and Gd on the fate of ARGs and MRGs in an activated sludge system.The diversity and relative abundance of ARGs,MRGs,and mobile genetic elements(MGEs)were detected by metagenomic sequencing.The results revealed an increased abundance of ARGs but a decreased abundance of MRGs under the joint effect of SMX and Gd.In addition,Gd alone exerted adverse effects on the proliferation and spread of ARGs and MRGs.However,SMX alone resulted in an increase in the diversity of ARGs and MRGs and promoted the growth of Pseudomonas,Thauera,and Streptomyces in the activated sludge system.Interestingly,a positive correlation was observed between most ARGs and MGEs.These findings provide comprehensive insights into the effects of co-occurring REEs and antibiotics on the fate of ARGs,MRGs,and MGEs,providing evidence to assist in controlling the spread and proliferation of ARGs and MRGs in activated sludge systems.