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Toxic heavy metal exposure and insufficiency or excess of essential heavy metals may have negative effects on pregnant women's health and fetal growth. To date, the predictors of pregnant women's heavy metal exposure levels remain unclear and vary with different regions. The study intended to explore potential predictors of exposure to heavy metals individually and high co-exposure to heavy metal mixtures. We recruited 298 pregnant women in first trimester from prenatal clinics in Jinan, Shandong Province, China, and collected spot urine samples and questionnaire data on their demographic characteristics, lifestyle habits, consumption of food and dietary supplement, and residential environment. All urine samples were analyzed for seven heavy metals: cobalt (Co), molybdenum (Mo), strontium (Sr), arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg). Factors associated with single heavy metal concentration were as follows: a) urinary As, Sr and Cd increased with women's age respectively; b) pregnant women with higher monthly household income per capita had lower Sr and Mo levels; c) pregnant women with intermittent folic acid supplementation and those not taking tap water as domestic drinking water had lower Sr concentrations; d) Cd was positively linked with consumption frequency of rice; e) Hg was adversely related to consumption frequency of egg and the women who took purified water as domestic drinking water had lower Hg exposure. In addition, pregnant women's age was positively associated with odds of high co-exposure to Co, As, Sr, Mo, Cd and Pb; while those with an educational level of college had lower odds of high exposure to such a metal mixture compared with those whose educational levels were lower than high school. Predictors of single urinary heavy metal concentration included pregnant women's age (As, Sr and Cd), monthly household income per capita (Sr and Mo), folic acid supplementation (Sr), rice consumption frequency (Cd), egg consumption frequency (Hg) and the type of domestic drinking water (Sr and Hg). Pregnant women with older age, lower educational level tended to have high co-exposure to Co, As, Sr, Mo, Cd and Pb. [ABSTRACT FROM AUTHOR]

A severe Cr-contaminated site was left after the demolition of a Chemical plant. Based on the preliminary monitoring results and related literature data, this paper studied how to prevent and control the possible contamination from the site to Jialing River effectively, which is building an intercept contamination dam in the side of the contaminated site along Jialing River and constructing leachate collection system in the site. This is the antifouling effect: in the same stratum of the same elevation, the Cr 6+ content inside the intercept contamination dam (soil:144.8 mg/kg∼827.4 mg/kg, leaching solution: 7.3 mg/L∼55.1 mg/L) is higher than that of the outside (soil:10.4 mg/kg∼64.9 mg/kg, leaching solution: 0.27 mg/L∼0.63 mg/L); Water level of monitoring hole inside the dam is higher than that of the outside; the water level difference is 3.26m to 5.39m. The disaster controlling for the site provides security for the later contamination remediation and the river environment protection. [ABSTRACT FROM AUTHOR]

Abstract: Al-4.7Mg-0.7Mn-0.3Er alloy plates were welded by laser beam welding (LBW) and tungsten inert gas (TIG). Mechanical properties and microstructures of both welded joints were analyzed. The results showed that the tensile strength of LBW joint was 315MPa, which was approximately 10% higher than that of TIG welded joint. This was attributed to the fine grains, dispersed primary Al3Er phase and low Mg evaporation in LBW weld. Equiaxed grains with average size of 30μm were obtained in the fusion zone, which were much smaller than that of 90μm in the fusion zone of TIG joint, due to the low heat input during LBW process. Moreover, finer primary Al3Er particles were uniformly distributed in the LBW joints, which resulted in a substantial increase of nucleation rate in LBW welds. In addition, it was also found that Mg concentrations in the fusion zones, in both TIG and LBW joints, were lower than that of the base one tested by EPMA. The burning loss rates of Mg in TIG and LBW joints were 36% and 22%, respectively. [Copyright &y& Elsevier]

Abstract: Samples of Al–Mg–Mn–Zr–Er alloys have been welded using the method of TIG welding. Microstructures characterization was performed by optical microscopy (OM), energy dispersive X-ray (EDX) and transmission electron microscopy (TEM), respectively. In addition, tensile and hardness test was conducted. The relationship between mechanical properties and microstructure of welded joints is evaluated. Results indicate that the ultimate tensile strength of the joints is 72% of that of the base metal. The base metal consists of a typical rolled structure, and the fusion zone (FZ) is mainly made up of dendrite grains. A characteristic equiaxed zone (EQZ) is obtained at the fusion boundary between the base metal and fusion zone. Fine dispersion of coherent Al3Er precipitates was found in the base metal, however, the quantity of these particles dropped significantly in the fusion zone. The hardness test results indicate that the microhardness in the fusion zone is lower than that of the base metal, due to the as-cast structure in this region. Based on the present work, it is concluded that TIG welding is the suitable welding procedure for joining this new type Er-containing aluminum alloy. [Copyright &y& Elsevier]

Hydrogen engines show great potential as a power source with good combustion performance, zero carbon emissions, and diverse sources. However, the exhaust emission characteristics with high water vapor (H 2 O) content have not yet been clarified. This study presents the exhaust emissions of a heavy-duty direct-injection hydrogen engine under various operational parameters, with a focus on the H 2 O content. The results reveal important exhaust emissions characteristics of the hydrogen engine, including lower exhaust temperature (200 °C–400 °C), higher unburned H 2 emissions (up to 17100 ppm), less nitrogen oxide (NO) generation (<1000 ppm), and higher H 2 O content (6%–40%). Additionally, unburned H 2 rises, and NO and H 2 O decrease as the excess air ratio (λ) increases. When λ is greater than 3, NO levels fall sharply to below 100 ppm. Optimal emissions performance is achieved with a 5 °CA BTDC ignition timing where low levels of H 2 , H 2 O, and NO are maintained. Increasing hydrogen injection pressure decreases H 2 but raises exhaust temperature, H 2 O, and NO emissions. Excessively delaying hydrogen injection timing adversely affects the concentration gradient in the cylinder, increasing unburned H 2 emissions. The best emissions performance is observed at a hydrogen injection timing of 110 °CA BTDC. • Studied the exhaust emissions of heavy-duty direct-injection hydrogen engine. • Clarified the high H 2 O and H 2 emission characteristics of hydrogen engines. • Analyzed lower NO emissions and exhaust temperature from hydrogen engines. • Explored the effects of operating conditions on emission characteristics. [ABSTRACT FROM AUTHOR]

Haemophilus parasuis ( H. parasui s) is a swine pathogen responsible for the Glässer's disease, which has received more attention in the past decade due to the increasing economic losses in the pig industry worldwide. As traditional inactive vaccine of H. parasui s has obvious disadvantage, to identify efficient immunoprotective antigens would undoubtedly contribute to the development of novel subunit vaccines. The putative secreted proteins of H. parasuis are potentially essential components of more potent vaccines. In the present study, six secreted proteins (PflA, Gcp, Ndk, HsdS, RnfC and HAPS_0017) were selected from the annotated H. parasuis serovar 5 genome as immunogenic protein with bioinformatic and experimental approaches. These proteins were successfully expressed in Escherichia coli and their immunogenicity was assessed in a mouse challenge model. The results showed that subcutaneous injection with the recombinant proteins resulted in the production of antibodies with high levels. Antigen-specific lymphoproliferative responses were detected in the splenocytes of the immunized animals. CD4 + T-cell populations were higher in the vaccinated animals 3 weeks after the booster immunization than those of the control animals. A significant increase was observed in the cytokine levels of IL-2, IL-4 and IFN-γ in the culture supernatants of splenocytes. Furthermore, immunized mice conferred different levels of protection against challenge with a lethal dose of highly virulent serovar 5 strain (H46). Our results indicate that these six secreted proteins induced a good Th1 response and protection against H. parasuis infection, could be potential subunit vaccine candidates. [ABSTRACT FROM AUTHOR]

Objective: To explore the association of circadian rhythm disruption with polycystic ovary syndrome (PCOS) and the potential underlying mechanism in ovarian granulosa cells (GCs).Design: Multicenter questionnaire-based survey, in vivo and ex vivo studies.Setting: Twelve hospitals in China, animal research center, and research laboratory of a women's hospital.Patients/animals: A total of 436 PCOS case subjects and 715 control subjects were recruited for the survey. In vivo and ex vivo studies were conducted in PCOS-model rats and on ovarian GCs collected from women with PCOS and control subjects.Intervention(s): The PCOS rat model was established with the use of testosterone propionate.Main Outcome Measure(s): Assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq), RNA sequencing, rhythmicity analysis, functional enrichment analysis.Result(s): There was a significant correlation between night shift work and PCOS. PCOS-model rats presented distinct differences in the circadian variation of corticotropin-releasing hormone, adrenocorticotropic hormone, prolactin, and a 4-h phase delay in thyrotropic hormone levels. The motif enrichment analysis of ATAC-seq revealed the absence of clock-related transcription factors in specific peaks of PCOS group, and RNA sequencing ex vivo at various time points over 24 hours demonstrated the differential rhythmic expression patterns of women with PCOS. Kyoto Encyclopedia of Genes and Genomes analysis further highlighted metabolic dysfunction, including both carbohydrate and amino acid metabolism and the tricarboxylic acid cycle.Conclusion(s): There is a significant association of night shift work with PCOS, and genome-wide chronodisruption exists in ovarian GCs. [ABSTRACT FROM AUTHOR]

Diabetes is a high-risk factor for neurocognitive dysfunction. Diabetic acute hyperglycaemia accompanied by high osmotic pressure can induce immune cell dysfunction, but its mechanism of action in brain microglia remains unclear. This study aimed to evaluate the role of the mechanically sensitive ion channel Piezo1 in the dysfunction of microglia in acute hyperglycaemia. To construct an in vitro acute hyperglycaemia model using the BV2 microglial cell line, Piezo1 in microglia was inhibited by GsMTx4 and siRNA, and the changes in microglial function were further evaluated. High concentrations of glucose upregulated the expression of Piezo1, led to weakened cell proliferation and migration, and reduced the immune response to inflammatory stimulating factors (Aβ and LPS). Additionally, LPS upregulated Piezo1 in BV2 microglial cultures in vitro. The activation of Piezo1 channels increased the intracellular Ca2+ concentration and reduced the phosphorylation of JNK1 and mTOR. Inhibiting Piezo1 did not affect cell viability at average glucose concentrations but improved acute HCG-induced cell damage and increased the phosphorylation of JNK1 and mTOR, suggesting that the latter modification may be a potential downstream mechanism of Piezo1. Piezo1 is necessary for microglial damage in acute hyperglycaemia and may become a promising target to treat hyperglycaemic brain injury. [ABSTRACT FROM AUTHOR]

• Ultrasound-assisted field was utilized to synthesize Pd/Ce 0.4 Zr 0.5 La 0.05 Y 0.05 O 1.95 catalysts for the low-temperature combustion of CH 4. • Ultrasonic external field effectively increased the specific surface area of the catalyst and decreased the particle size. • The catalytic activity of methane combustion catalysts can be improved with the application of an appropriate level of ultrasonic power. In this work, ultrasound-assisted sol–gel (UASG) and wet incipient impregnation (WIP) methods were employed to synthesize a series of Ce 0.4 Zr 0.5 La 0.05 Y 0.05 O 1.95 oxygen storage materials (OSM) and Pd/Ce 0.4 Zr 0.5 La 0.05 Y 0.05 O 1.95 catalysts under different frequency ultrasound external field. The effect of the ultrasonic external field on the low-temperature catalytic activity of the catalyst was investigated. The BET and TEM results demonstrated that ultrasound field can increase the catalyst's specific surface area by 25% and decrease the particle size from 10.1 nm to 7.3 nm. The XPS results showed that the concentrations of surface Pd2+, O ads , and Ce3+ species increased from 21%, 44%, and 43% to 42%, 65%, and 46%, respectively, enhancing the formation of Pd2+, O ads and Ce3+ species on the catalyst surface. The performance tests revealed that T 90 (CH 4) of the prepared Pd/Ce 0.4 Zr 0.5 La 0.05 Y 0.05 O 1.95 catalyst by UASG method decreased from 536 ℃ to 331 ℃, improving its low-temperature catalytic activity. Additionally, the catalysts synthesized using by UASG method exhibited the enhanced resistance to water and sulfur poisoning and maintained their catalytic performance for 20 h. [ABSTRACT FROM AUTHOR]

• The addition of Niobium can improve the catalytic performance of Pt-based catalyst. • The addition of Niobium enables the presence of Platinum in the catalyst as a metallic state. • The addition of Niobium can improve the thermal stability and anti-sulfur performance of the catalyst. With the improvement of current global vehicle emission standards increase and widespread application of natural gas vehicles (CNG), existing three-way catalytic converters (TWCs) need to be modified to meet the new emission regulations. In recent years, the price of palladium has been rising, while platinum, which is also used in catalytic systems, is relatively cheap, and the industry has come up with the idea of replacing palladium with platinum. Palladium loaded with a mass fraction of 1% on Ce 0.4 Zr 0.5 La 0.05 Y 0.05 O 1.95 (CZLY) did show excellent catalytic activity, however, when palladium is replaced by platinum, the catalytic activity of the catalyst for methane combustion is significantly reduced. At 680 °C under oxygen-rich conditions (20%), methane conversion can typically reach 90%. The reduced 1% Pt/CZLY catalyst, on the other hand, was unstable in activity at high temperatures, although it was significantly higher at the starting temperature (T 50 = 378 °C). In this work, it was found that the addition of niobium to CZLY improved the activity of Pt-based catalysts. The 1% Pt/Ce 0.4 Zr 0.5 La 0.05 Nb 0.05 O 2 (1% Pt/CZLN) catalysts showed a decrease in T 90 (CO) of 26 °C and T 90 (CH 4) of approximately 250 °C. The activity of this catalyst is consistent with that of the reduction pre-treatment 1% Pt/CZLY catalyst. Results from thermal deactivation and sulphur poisoning experiments show that the 1% Pt/CZLN catalyst exhibits superior thermal stability and anti-sulphur toxicity. For example, methane conversion of the 1% Pt/CZLN catalyst maintained at 85% at 600 °C for 32 h with a 5% decrease in activity. To clearly explain the effect of niobium doping on the catalyst, BET, XRD, H 2 -TPR, XPS and TEM tests were performed on the catalysts confirming that the strong Pt-Nb interaction stabilizes the valence state of the platinum and loads the platinum on the carrier surface in the active metallic platinum state. The amount of niobium doping was positively correlated with the metallic Pt content in the catalyst. In conclusion, the addition of niobium to platinum-based catalysts increases the methane combustion activity of the catalyst and delays thermal deactivation and sulphur poisoning of the platinum-based catalyst, extending the service life of the platinum-based catalyst. [ABSTRACT FROM AUTHOR]

Abstract High altitude shows a great influence on vehicle emissions because of lower pressure and shortage of oxygen concentrations. In addition, type approval test of light duty vehicle is usually carried out below the elevation of 1000 m. In order to address the effect of high altitude on vehicle emissions, real driving emission (RDE) test procedure has been introduced in China VI emission regulation. Thus, the effects of altitude on the emissions from a China IV certificated light-duty diesel vehicle under real road driving conditions were investigated in this work. Research results show that CO emissions increased with the elevated altitude. At the altitude of 2990 m, the CO emissions increased by 209% in comparison with that of near sea level in whole test cycle. At specific test modes, CO emissions follow the sequence of urban > rural > motorway. Both PN and NO x emissions also rose with altitude while NO x emissions at 2990 m showed a decreasing tendency. In addition, different tendency between high altitudes and relative low altitudes was observed under specific test modes, which was probably related to the function of after-treatment device. Highlights • The effect of altitude on vehicle emissions under RDE has been studied. • There is great influence of after-treatment on the vehicle emissions. • NOx emissions slightly decrease at 2990 m in whole test cycle. • Different tendency occurs for NOx and PN emissions in specific test modals. [ABSTRACT FROM AUTHOR]

Haemophilus parasuis infection is of considerable economic importance in the swine industry due to high morbidity and mortality in naive swine populations. Accurate detection and identification of the causative agent are difficult, yet necessary, for disease control. In this study, a simple and rapid method of cross-priming amplification (CPA) with a vertical flow (VF) visualization strip was established to detect H. parasuis . The reaction can specifically identify 15 serovar reference strains and 57 clinically isolated strains of H. parasuis , with a detection limit of 14 CFU. The performance of the CPA-VF assay was evaluated and compared with that of species-specific PCR by testing 62 clinical culture-positive specimens of H. parasuis . The entire process, from specimen processing to analysis of the results, can be completed in 2 h without a complicated apparatus. The convenience and speed of the CPA-VF assay in this study make it a suitable choice for epidemiological investigation and point-of-care testing (POCT) for H. parasuis infection. [ABSTRACT FROM AUTHOR]

• The key deactivation factor depends on the structural stability of CZ solid solution. • Hydrothermal aging is favorable for improving PGM dispersion and active sites exposure. • Accumulation of stable formate and bicarbonate intermediates inhibits the proceeding reactions. Commercial three-way catalysts with high-activity and long-term durability are critical for the aftertreatment of compressed natural gas vehicle exhausts to meet increasingly stringent policy requirements, but high concentrations of CH 4 and H 2 O in the exhaust gas make the catalyst susceptible to deactivation. In this work, a series of commercially deactivated and aged honeycomb Pt/Pd/Rh/CeO 2 -ZrO 2 /Al 2 O 3 catalysts were obtained by dry-aging, hydrothermal-aging and engine bench-aging methods, and the effects of aging conditions on catalytic performance, surface composition and microstructure evolution were investigated. The combinations of H 2 -TPR, XRD, Raman, HRTEM, XPS and in situ DRIFTS of CO/CH 4 characterizations confirmed that the stability of CeO 2 -ZrO 2 solid solution structure is a key factor affecting the catalytic activity and durability. Hydrothermally-aged catalyst has a relatively stable CeO 2 -ZrO 2 solid solution structure, which ensures a high dispersion of precious metal particles in the form of small particles on the catalyst surface. Dry-aged catalyst shows that more CeO 2 crystals have been segregated from CeO 2 -ZrO 2 solid solution, resulting in most precious metal particles in the form of agglomerates. For the deactivated catalysts after engine bench aging, the microstructure was significantly changed with a large number of CeO 2 crystals detached from CeO 2 -ZrO 2 solid solution, resulting in more active sites of Platinum Group Metal (PGM) being encapsulated. In situ DRIFTS of CH 4 experiments showed that the process of generation and depletion of intermediate species (e.g., methoxy, formate and bicarbonate species) is a matching process. For the deactivated catalysts with fewer active sites, the subsequent reaction steps of these intermediate species to CO 2 and H 2 O are hindered by the accumulation of stable formate and bicarbonate intermediate species. [ABSTRACT FROM AUTHOR]

Haemophilus parasuis is the causative agent of Glässer's disease, which causes high morbidity and mortality in piglets, leading to severe economic losses. The lack of a commercial vaccine against a broad spectrum of strains has limited the disease control. H. parasuis outer membrane proteins (OMPs) are potentially essential components for vaccine formulation. In this study, seven putative OMPs were selected from the annotated H. parasuis serovar 5 genome; they were predicted by bioinformatics and annotated as potential virulence-related factors. These proteins were cloned, expressed, and purified as His-tagged proteins . Antigenicity of the candidate proteins was assessed using Western blotting with convalescent sera against H. parasuis serovar 5. The immunogenicity of the seven OMPs was assessed in a guinea pig model. Except VacJ, all the other six recombinant proteins elicited a detectable antibody response. Antisera against four of the selected proteins effectively killed the bacteria in vitro . Three proteins (Omp26, VacJ, and HAPS_0742) were found to confer significant protection against challenge with a lethal dose of H. parasuis in a guinea pig model. The results suggest that these three proteins have a strong potential to be vaccine candidates against Glässer's disease. [ABSTRACT FROM AUTHOR]

• Rh-only catalyst has been shown to have the potential to improve CO and NOx conversions when as a downstream catalyst. • Rhodium and palladium differ significantly in terms of their activity towards N 2 O and NH 3 formation. • Rh-only catalyst was shown to generate the highest amount of N 2 O and the Pd-only catalyst the highest amount of NH 3. With the increase in worldwide automobile usage and the tightening of associated emissions legislation, the total demand of PGMs for use in automotive emission control catalysts is growing. Reducing the amount of required PGM in automotive catalysts as well as maintaining or improving the associated catalytic performance is an area of significant focus. This work presents a comparative study of the catalytic activity of Pd-only, Pd/Rh and Rh-only catalyst systems with respect to CO, HC and NO x conversion. The Rh-only catalyst has been shown to have the potential to improve CO and NO x conversions when functioning as a downstream catalyst compared with a Pd/Rh catalyst as well as reducing the usage of precious metals. In addition the formation of the three way catalysis by-products N 2 O and NH 3 in different catalyst systems was investigated. The temperature of N 2 O and NH 3 formation was shown to correlate with NO x light off temperatures and to vary depending upon the catalyst system employed and ageing conditions. The Rh-only catalyst was shown to generate the highest amount of N 2 O and the Pd-only catalyst the highest amount of NH 3. [ABSTRACT FROM AUTHOR]