The protective influence of family support on anxiety, depressive symptoms, and suicidal ideation among elderly Chinese nursing home residents: A study of serial mediation.

In light of the aging demographic in China, heightened attention is warranted for the mental well-being of elderly individuals. Nevertheless, the prevalence of suicidal ideation among older residents in Chinese nursing homes and the nuanced impact of family support on this phenomenon, mediated by anxiety and depressive symptoms, remain unclear. A cohort of 506 Chinese elderly adults participated in the study. Psychosocial traits were assessed using the Perceived Social Support from Family scale (PSS-Fa) for family support, the 7-item Generalized Anxiety Disorder scale (GAD-7) for anxiety symptoms, the 9-item Patient Health Questionnaire (PHQ-9) for depressive symptoms, and suicidal ideation. A structural equation model (SEM) was employed to execute a serial mediation model. The analysis of 506 elderly adults revealed that 8.1% reported varying levels of suicidal ideation within Chinese nursing homes. The pathway from family support to anxiety symptoms (standardized beta = -0.025, P = .241), family support to depressive symptoms (standardized beta = -0.072, P < .05), and family support to suicidal ideation (standardized beta = -0.082, P < .05) were explored. Additionally, pathways from anxiety symptoms to suicidal ideation (standardized beta = 0.364, P < .001), anxiety symptoms to depressive symptoms (standardized beta = 0.647, P < .001), and depressive symptoms to suicidal ideation (standardized beta = 0.369, P < .001) were examined. This study elucidated the underlying mechanisms connecting family support to suicidal ideation, with depressive symptoms partially mediating this association. Additionally, our discoveries shed light on the partial mediation of anxiety symptoms by depressive factors when it came to the realm of suicidal ideation.

Aquaporin-8 transports hydrogen peroxide to regulate granulosa cell autophagy.

Aquaporin-8 (AQP8), a member of the aquaporin family, is strongly expressed in follicular granulosa cells, which could affect the hormone secretion level in females. AQP8, as a membrane protein, could mediate H2O2 into cells, thereby triggering various biological events. The deficiency of Aqp8 increases female fertility, resulting from the decrease in follicular atresia. The low cell death rate is related to the apoptosis of granulosa cells. However, the mechanism by which AQP8 regulates the autophagy of granulosa cells remains unclear. Thus, this study aimed to explore the effect of AQP8 on autophagy in follicular atresia. We found that the expression of the autophagy marker light-chain protein 3 was significantly downregulated in the granulosa cells of Aqp8-knockout (Aqp8 -/- ) mice, compared with wild-type (Aqp8 +/+ ) mice. Immunofluorescence staining and transmission electron microscopic examination indicated that the number of autophagosomes in the granulosa cells of Aqp8 -/- mice decreased. Using a follicular granulosa cell autophagy model, namely a follicular atresia model, we verified that the concentration of H2O2 significantly increased during the autophagy of granulosa cells, consistent with the Aqp8 mRNA level. Intracellular H2O2 accumulation was modulated by endogenous AQP8 expression level, indicating that AQP8-mediated H2O2 was involved in the autophagy of granulosa cells. AQP8 deficiency impaired the elevation of H2O2 concentration through phosphorylated tyrosine activation. In addition, we carried out the analysis of transcriptome sequencing datasets in the ovary and found there were obvious differences in principal components, differentially expressed genes (DEGs) and KEGG pathways, which might be involved in AQP8-regulated follicular atresia. Taken together, these findings indicated that AQP8-mediated H2O2 transport could mediate the autophagy of granulosa cells. AQP8 might be a potential target for diseases related to ovarian insufficiency.

Endocytic degradation of ErbB2 mediates the effectiveness of neratinib in the suppression of ErbB2-positive ovarian cancer.

The tyrosine kinase receptor ErbB2 is frequently found to be overexpressed in multiple cancer types. Targeted therapeutic approaches against ErbB2 have shown promising results and received FDA approvals in the treatment of breast cancer. However, this approach has not been granted in ovarian cancers till now. In order to assess the validity of ErbB2-targeted therapy in ovarian cancer, we investigated the effectiveness of two FDA-approved tyrosine kinase inhibitors of ErbB2, lapatinib and neratinib, on the growth of ovarian cancers. We observed that both lapatinib and neratinib displayed inhibitory effects towards the proliferation and migration of ErbB2-positive ovarian cancer cells in vitro, with neratinib showing stronger suppression in general. Neratinib treatment led to the reduction of ErbB2 protein levels, with concomitant attenuation of the phosphorylation of AKT, MEK, and ERK1/2. Immunofluorescence assays revealed that neratinib induced the internalization and lysosomal degradation of ErbB2, which was accompanied by its hyperubiquitylation. Lapatinib and neratinib also repressed the in vivo growth of SKOV3 cells, and neratinib downregulated ErbB2 levels in xenograft tumors to cause potent inhibition. Therefore, the ubiquitylation-mediated endocytic degradation of ErbB2 incurred by neratinib treatment conferred potent inhibition of ovarian cancer growth. Clinical investigations of neratinib in ErbB2-positive ovarian cancer are warranted.

Investigation of aerosol and gas emissions from a coal-fired power plant under various operating conditions.

The concentrations of fine particles and selected gas pollutants in the flue gas entering the stack were measured under several common operation modes in an operating coal power plant producing electricity. Particle size distributions in a diameter range from 10 nm to 20 µm were measured by a scanning mobility particle sizer (SMPS), and the flue gas temperature and concentrations of CO2 and SO2 were monitored by a continuous emission monitoring system (CEMS). During the test campaign, five plant operating modes were studied: soot blowing, bypass of flue-gas desulfurization (FGD), reheat burner operating at 0% (turned off), 27%, and 42% (normal condition) of its full capacity. For wet and dry aerosols, the measured mode sizes were both around 40 nm, but remarkable differences were observed in the number concentrations (#/cm3, count per square centimeter). A prototype photoionizer enhanced electrostatic precipitator (ESP) showed improved removal efficiency of wet particles at voltages above +11.0 kV. Soot blowing and FGD bypass both increased the total particle number concentration in the flue gas. The temperature was slightly increased by the FGD bypass mode and varied significantly as the rating of reheat burner changed. The variations of CO2 and SO2 emissions showed correlations with the trend of total particle number concentration possibly due to the transitions between gas and particle phases. The results are useful in developing coal-fired power plant operation strategies to control fine particle emissions and developing amine-based CO2 capture technologies without operating and environmental concerns associated with volatile amine emissions.Implications: The measurement of the fine particle size distributions in the exhaust gas under several common operating conditions of a coal-fired power plant revealed different response relations between aerosol number concentration and the operating condition. A photo-ionizer enhanced ESP was demonstrated to capture fine particles with higher efficiency compared to conventional ESPs, and the removal efficiency increased with the applied voltage. The characteristic information of aerosols and main gaseous pollutants in the exhaust gas is extremely important for developing and deploying CO2 scrubbers, whose amine emissions and operating effectiveness depends greatly on the upstream concentrations of fine particles, SO2, from the power plant.

Surfactants Facilitating Carbonic Anhydrase Enzyme-Mediated CO2 Absorption into a Carbonate Solution.

Carbonic anhydrase (CA) enzyme-mediated absorption processes are regarded as promising alternatives to the conventional amine-based process for CO2 capture because of their low energy penalty and low risk of causing secondary pollution. The activity and stability of the CA enzyme are crucial to reducing the equipment and operating costs of the enzyme-mediated process. This work investigated three cationic and nonionic surfactants to improve the activity and stability of a technical-grade CA enzyme in a 20 wt % potassium carbonate solution. Experimental results revealed that the impact of the surfactants on the CA enzyme depended on their properties. For example, the cationic surfactant significantly enhanced the activity of CA enzyme but adversely affected enzyme stability. However, in the presence of the cationic surfactant after 30 days at 50 °C, the activity of the CA enzyme still outperformed that of CA without added surfactant. The nonionic surfactant significantly improved enzyme stability. Furthermore, the addition of surfactants within a critical micelle concentration of 1.0 did not distinctly influence the gas-liquid mass transfer, indicating that surfactant-enzyme interaction was responsible for the observed variations in the activity and stability of the tested enzyme.

Enhanced stability and chemical resistance of a new nanoscale biocatalyst for accelerating CO2 absorption into a carbonate solution.

A novel potassium-carbonate-based absorption process is currently being developed to reduce the energy consumption when capturing CO2 from coal combustion flue gas. The process employs the enzyme carbonic anhydrase (CA) as a catalyst to accelerate the rate of CO2 absorption. This study focused on the immobilization of a new variant of the CA enzyme onto a new group of nonporous nanoparticles to improve the enzyme's thermal stability and its chemical resistance to major impurities from the flue gas. The CA enzyme was manufactured at the pilot scale by a leading enzyme company. As carrier materials, two different batches of SiO2-ZrO2 composite nanoparticles and one batch of silica nanoparticle were synthesized using a flame spray pyrolysis method. Classic Danckwerts absorption theory with reaction was applied to determine the kinetics of the immobilized enzymes for CO2 absorption. The immobilized enzymes retained 56-88% of their original activity in a K2CO3/KHCO3 solution over a 60-day test period at 50 °C, compared with a 30% activity retention for their free CA enzyme counterpart. The immobilized CA enzymes also revealed improved chemical stability. The inactivation kinetics of the free and immobilized CA enzymes in the K2CO3/KHCO3 solution were experimentally quantified.

Mechanical activation of CaO-based adsorbents for CO(2) capture.

The reversible cycling of CaO adsorbents to CaCO(3) for high-temperature CO(2) capture is substantially improved by mechanical treatment. The mechanical milling intensity and conditions of grinding (e.g., wet vs. dry, planetary vs. vibratory milling) were determined to be the main factors that control the effectiveness of the mechanochemical synthesis to enhance the recycling stability of the sorbents prepared. In addition, MgO was used as an example of an inert binder to help mitigate CaCO(3) sintering. Wet planetary milling of MgO into CaCO(3) allowed efficient particle size reduction and the effective dispersion of MgO throughout the particles. Wet planetary milling yielded the most stable sorbents during 50 cycles of carbonation-calcination.

Sintering of calcium oxide (CaO) during CO2 chemisorption: a reactive molecular dynamics study.

Reactive dynamics simulations with the reactive force field (ReaxFF) were performed in NVE ensembles to study the sintering of two solid calcium oxide (CaO) particles with and without CO(2) chemisorption. The simulated sintering conditions included starting adsorption temperatures at 1000 K and 1500 K and particle separation distances of 0.3 and 0.5 nm. The results revealed that the expansion of sorbent particles during CO(2) chemisorption was attributed to the sintering of two CaO-CaO particles. Increasing the adsorption temperature resulted in more particle expansion and sintering. The shorter the distance between two particles, the faster the rate of sintering during CO(2) adsorption. A detailed analysis on atom spatial variations revealed that the sorbent particles with a larger separation distance had a larger CO(2) uptake because of less sintering incurred. The chemisorptions of CO(2) on CaO particles sintered at high adsorption temperatures were also simulated to mimic the process of sorbent regeneration. It was found that regeneration would be more difficult for sintered particles than for fresh particles. In addition, a possible sintering barrier, magnesium oxide (MgO), was introduced to prevent CaO particles from sintering during CO(2) chemisorption. It was found that the MgO particles could reduce the sintering of CaO particles during CO(2) chemisorption. Simulation results from this study provided some guidelines on synthesizing or selecting sorbents with less sintering effect for multiple CO(2) adsorption-regeneration cycles.

Activity and stability of immobilized carbonic anhydrase for promoting CO2 absorption into a carbonate solution for post-combustion CO2 capture.

An Integrated Vacuum Carbonate Absorption Process (IVCAP) currently under development could significantly reduce the energy consumed when capturing CO2 from the flue gases of coal-fired power plants. The biocatalyst carbonic anhydrase (CA) has been found to effectively promote the absorption of CO2 into the potassium carbonate solution that would be used in the IVCAP. Two CA enzymes were immobilized onto three selected support materials having different pore structures. The thermal stability of the immobilized CA enzymes was significantly greater than their free counterparts. For example, the immobilized enzymes retained at least 60% of their initial activities after 90 days at 50 °C compared to about 30% for their free counterparts under the same conditions. The immobilized CA also had significantly improved resistance to concentrations of sulfate (0.4 M), nitrate (0.05 M) and chloride (0.3 M) typically found in flue gas scrubbing liquids than their free counterparts.

Intake fractions of industrial air pollutants in China: estimation and application.

Intake fractions, an emissions-intake relationship for primary pollutants, are defined and are estimated in order to make simple estimates of health damages from air pollution. The sulfur dioxide (SO2) and total suspended particles (TSP) intake fractions for five cities of China are estimated for the four main polluting industries-electric power generation, mineral (mostly cement) products industry, chemical process industry and metallurgical industry (mainly iron and steel smelting). The Industrial Source Complex Long Term (ISTLT3) model is used to simulate the spatial distribution of incremental ambient concentrations due to emissions from a large sample of site-specific sources. Detailed population distribution information is used for each city. The average intake fractions within 50 km of these sources are 4.4x10(-6) for TSP, and 4.2x10(-6) for SO2, with standard deviations of 8.15x10(-6) and 9.16x10(-6), respectively. They vary over a wide range, from 10(-7) to 10(-5). Although the electric power generation has been the focus of much of the air pollution research in China, our results show that it has the lowest average intake fraction for a local range among the four industries, which highlights the importance of pollutant emissions from other industrial sources. Sensitivity analyses show how the intake fractions are affected by the source and pollutant characteristics, the most important parameter being the size of the domain. However, the intake fraction estimates are robust enough to be useful for evaluating the local impacts on human health of primary SO2 and TSP emissions. An application of intake fractions is given to demonstrate how this approach provides a rapid population risk estimate if the dose-response function is linear without threshold, and hence can help in prioritizing pollution control efforts.

[The role of additives in bio-mass coal briquette on sulfur retention enhancement].

The research first conducted the sulfur-fixing experiment of bio-mass coal briquette in a tubular furnace. The impacts of three additives Al2O3, Fe2O3 and MnO2 on the sulfur retention by calcium-based sorbent in briquette were investigated, and only Al2O3 displayed the enhancement of sulfur retention. The TGA experiment was further carried out, and proved that the high-temperature decomposition of CaSO4 in the deoxidization atmosphere was effectively inhibited with the addition of Al2O3. The XPS and XRD analyses of briquette ash showed that due to the interaction among Al2O3, CaSO4 and CaO, the composite CaSO4.3CaO.3Al2O3 which has more thermal stability was formed. With its wrapping or binding onto the surface of CaSO4 crystal, the decomposition of CaSO4 was mitigated.

Emission inventories of NOx from commercial energy consumption in China, 1995-1998.

Emissions of nitrogen oxides (NOx) in China are of great concern because of their impact on local air pollution as well as on regional environmental risks such as acid rain, eutrophication, tropospheric ozone, fine particulate matter, and loss of biodiversity. In this paper, total anthropogenic emissions of NOx in China during the past two decades are estimated on the basis of commercial energy consumption and NOx emission factors of different sectors and fuel types. Specifically, emission inventories of NOx from 31 provinces, 7 economic sectors, and 11 fuel types from 1995 to 1998 are evaluated and analyzed in detail, and the distribution of provincial-based average NOx emission intensity in 1998 is presented. It can be seen that the calculated national total emissions of NOx have rapidly increased from 4.76 Mt in 1980 to a peak value of about 12.03 Mt in 1996, with an average annual growth rate of 6%. However, instead of increasing, NOx emissions in 1997 and 1998 decreased by 0.37 Mt and 0.85 Mt, respectively, as compared to the peak in 1996. In short, NOx emissions caused by energy use are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas. These results imply that China's NOx emissions in the future may not become as high as previously expected which will be helpful for policy making to control local NOx pollution as well as to reduce acid rain and tropospheric ozone in East Asia.