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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(5): 802-809, 2024 May 28.
Article in English, Chinese | MEDLINE | ID: mdl-39174894

ABSTRACT

OBJECTIVES: Postdoctoral researchers in Chinese universities commonly face a high risk of mental health issues, such as depression, yet the underlying causes and mechanisms remain unclear. This study aims to explore the influence of childhood socioeconomic status (SES) on depression among postdoctoral researchers and the mediating roles of current subjective SES and perceived stress in this process. METHODS: An online survey was conducted among postdoctoral researchers at a university. The survey included a general information questionnaire, the Childhood Socioeconomic Status Scale, the Subjective Socioeconomic Status Scale, the Perceived Stress Scale, and the Patient Health Questionnaire. A total of 505 valid responses were collected. Pearson correlation analysis was used to analyze the data, and the PROCESS macro was employed for chain mediation analysis. RESULTS: Childhood SES was significantly positively correlated with current subjective SES (P<0.05) and significantly negatively correlated with postdoctoral tenure, perceived stress, and depression (all P<0.05). Current subjective SES was significantly negatively correlated with perceived stress and depression (both P<0.05), while perceived stress was significantly positively correlated with depression (P<0.05). The chain mediation effect of childhood SES → current subjective SES → perceived stress → depression was significant (P<0.05). CONCLUSIONS: Childhood socioeconomic status can influence depression among postdoctoral researchers through the mediating roles of current subjective socioeconomic status and perceived stress. These findings provide a target for the prevention and intervention of depression in postdoctoral populations and offer a reference for the development of mental health promotion strategies for young university faculty.


Subject(s)
Depression , Social Class , Stress, Psychological , Humans , Stress, Psychological/psychology , Universities , Depression/etiology , Depression/psychology , Surveys and Questionnaires , Female , Male , Research Personnel/psychology , Research Personnel/statistics & numerical data , China/epidemiology , Adult
2.
J Hazard Mater ; 476: 134878, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-38897115

ABSTRACT

Micro- and nanoplastic pollution has emerged as a significant global concern due to their extensive presence in the environment and potential adverse effects on human health. Nanoplastics can enter the human circulatory system and accumulate in the liver, disrupting hepatic metabolism and causing hepatotoxicity. However, the precise mechanism remains uncertain. Lipophagy is an alternative mechanism of lipid metabolism involving autophagy. This study aims to explore how polystyrene nanoplastics (PSNPs) influence lipid metabolism in hepatocytes via lipophagy. Initially, it was found that PSNPs were internalized by human hepatocytes, resulting in decreased cell viability. PSNPs were found to induce the accumulation of lipid droplets (LDs), with autophagy inhibition exacerbating this accumulation. Then, PSNPs were proved to activate lipophagy by recruiting LDs into autophagosomes and block the lipophagic flux by impairing lysosomal function, inhibiting LD degradation. Ultimately, PSNPs were shown to activate lipophagy through the AMPK/ULK1 pathway, and knocking down AMPK exacerbated lipid accumulation in hepatocytes. Overall, these results indicated that PSNPs triggered lipophagy via the AMPK/ULK1 pathway and blocked lipophagic flux, leading to lipid accumulation in hepatocytes. Thus, this study identifies a novel mechanism underlying nanoplastic-induced lipid accumulation, providing a foundation for the toxicity study and risk assessments of nanoplastics.


Subject(s)
AMP-Activated Protein Kinases , Autophagy-Related Protein-1 Homolog , Autophagy , Hepatocytes , Lipid Metabolism , Polystyrenes , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Polystyrenes/toxicity , Autophagy-Related Protein-1 Homolog/metabolism , Autophagy/drug effects , Lipid Metabolism/drug effects , AMP-Activated Protein Kinases/metabolism , Lipid Droplets/metabolism , Lipid Droplets/drug effects , Nanoparticles/toxicity , Signal Transduction/drug effects , Microplastics/toxicity , Hep G2 Cells , Intracellular Signaling Peptides and Proteins/metabolism , Cell Survival/drug effects
3.
BMC Public Health ; 24(1): 1198, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38685094

ABSTRACT

BACKGROUND: Healthcare staff in China, especially females, work in a high-pressure, high-load, and high-risk environment, which affects the physical and mental health, the efficiency and quality of work, and increases turnover intention. The present study investigated the relationship between perceived stress and turnover intention in female healthcare staff, and the effects of future-oriented coping and work-family balance on this relationship. METHODS: Four hundred thirty-five female medical workers were recruited to perform a perceived stress scale, future-oriented coping inventory, work-family balance scale and turnover intention scale. Meanwhile, serial multiple mediation analysis was performed using PROCESS. RESULTS: 1) Perceived stress positively predicted the level of turnover intention in female healthcare staff; 2) Preventive coping and proactive coping showed mediation effects on the relationship between perceived stress and turnover intention, and preventive coping positively related to proactive coping; 3) The work-family balance also showed mediation effects on the relationship between perceived stress and turnover intention; 4) Preventive coping, proactive coping and work-family balance showed a serial multiple mediation on the relationship between perceived stress and turnover intention in female healthcare workers. CONCLUSIONS: Perceived stress affects the level of turnover intention in female healthcare staff through preventive coping, proactive coping, and work-family balance. In addition, the sequential model of future-oriented coping was validated among female healthcare staff.


Subject(s)
Adaptation, Psychological , Health Personnel , Intention , Personnel Turnover , Humans , Female , Personnel Turnover/statistics & numerical data , Adult , China , Health Personnel/psychology , Health Personnel/statistics & numerical data , Middle Aged , Occupational Stress/psychology , Occupational Stress/epidemiology , Stress, Psychological/psychology , Mediation Analysis , Surveys and Questionnaires , Young Adult
4.
J Environ Manage ; 341: 118107, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37156022

ABSTRACT

Microplastics (MPs) in water pose a great threat to the ecological environment, but the impact of MPs on constructed wetland microbial fuel cells (CW-MFCs) has not been studied, so in order to fill the research gap and enrich the research in the field of microplastics, a 360-day experiment was designed to determine the operating status of CW-MFCs at different concentrations (0, 10, 100 and 1000 µg/L) polyethylene microplastics (PE-MPs) at different times, focusing on the changes of the CW-MFCs' ability to handle pollutants, power production performance and microbial composition. The results showed that with the accumulation of PE-MPs, the removal effect of COD and TP did not change significantly, and that the removal rate was maintained at around 90% and 77.9% respectively, within 120 d of operation. What's more, the denitrification efficiency increased (from 4.1% to 19.6%), but with the passage of time, it decreased significantly (from 7.16% to 31.9%) at the end of the experiment, while oxygen mass transfer rate was significantly increased. Further analysis showed that the accumulation of PE-MPs did not affect the current power density significantly with the changes of time and concentration, but the accumulation of PE-MPs would inhibit the exogenous electrical biofilm and increase the internal resistance, thereby affecting the electrochemical performance of the system. In addition, the results of microbial PCA showed that the composition and the activity of the microorganisms were changed under the action of PE-MPs, that the microbial community in CW-MFC showed a dose effect on the input of PE-MPs, and that the relative abundance of nitrifying bacteria with time was significantly affected by PE-MPs concentration. The relative abundance of denitrifying bacteria decreased over time, but PE-MPs promoted the reproduction of denitrifying bacteria, which was consistent with the changes in nitrification and denitrification rates. The removal modes of EP-MPs by CW-MFC include the adsorption and the electrochemical degradation, with two isothermal adsorption models of Langmuir and Freundlich being constructed in the experiment, and the electrochemical degradation process of EP-MPs being simulated. In summary, the results show that the accumulation of PE-MPs can induce a series of changes in substrate, microbial species and activity of CW-MFCs, which in turn affects the pollutant removal efficiency and power generation performance during its operation.


Subject(s)
Bioelectric Energy Sources , Microplastics , Plastics , Polyethylene , Wetlands , Wastewater , Bacteria
5.
Bioresour Technol ; 326: 124777, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33540214

ABSTRACT

To investigate the effect of microplastics (MPs) particles in vermicomposting, polyethylene (PE) particles added into sludge. Results showed that the vermicomposting with high MPs addition obtained lower removal efficiencies for organics than the vermicomposting with low MPs addition. The content of DOC and NH4+-N in M4 reactor (with the highest MPs addition) at 80 days was 8.4 mg/kg and 74.2 mg/kg, respectively. The pH, C/N, electrical conductivity (EC), and germination index (GI) results showed that the addition amount of MPs was directly proportional to the negative effect of composting. The negative effect mainly occurred after 20 days of composting. High MPs addition resulted in apparent oxidative stress and neurotoxicity on earthworm, the values of catalase (CAT) and acetylcholine esterase (AChE) in M4 reactor increased by 2.03 times and 1.60 times. The bacteria in M4 were more barren and lower in terms of diversity.


Subject(s)
Composting , Oligochaeta , Animals , Microplastics , Plastics , Sewage , Soil
6.
Sci Total Environ ; 776: 145909, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-33639468

ABSTRACT

In order to eliminate the weak degradation ability of organic matter in sludge treatment wetland (STW). In current work, a combined biological power generation and earthworm assisted sludge treatment wetland (BE-STW) system is proposed for the first time to accelerate degradation and dehydration process of organics in STW, thusly, recovering biomass energy in sludge. Experimental results show that S4 system (earthworm and bioelectricity combined) yields a voltage of 0.832 V and maximum power density of 94.98 W/m2 in the 5th day. The combination of earthworm, microorganism and plants in STW system can reduce the ratio of volatile solids to total solids (VS/TS) to 15% while the removal rate of total chemical oxygen demand (TCOD) reaches 92.1%. The BE-STW system increases sludge particle size while reduces absolute value of Zeta and extracellular polymeric substances (EPS) content, so that the moisture content of effluent sludge retains to 66.8%. Meanwhile, the richness of bacterial communities in S4 proves that bioelectrochemistry and earthworm can effectively improve the sludge treatment effect.


Subject(s)
Oligochaeta , Sewage , Animals , Bacteria , Biological Oxygen Demand Analysis , Waste Disposal, Fluid , Wetlands
7.
Environ Sci Pollut Res Int ; 27(10): 10766-10777, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31942720

ABSTRACT

This study investigated the feature of phosphorus uptake by low-cost waste concrete. Adsorption isotherms, metal dissolution, influence of P concentration and temperature, as well as adsorbent regeneration were investigated. Chemical extraction, SEM, XRD, FTIR, and XPS were employed to determine the products of P sequestration. Results demonstrated that phosphate adsorption fitted the Langmuir isotherm model well, with estimated maximum phosphate adsorption capacity of 80.5 mg/g (10 °C). Of adsorbed phosphate, 72.1% could be desorbed when 0.1 M citrate buffer was used as eluant, and waste concrete could be recovered and reused for 4 times by the combination of eluting and roasting. Mechanisms including Ca/alkali dissolution, surface adsorption, and chemical precipitation are involved in the sequestration of phosphorus from wastewater by waste concrete. Weakly adsorptive phosphorus and Ca-P precipitate were the main products. P concentration was the major factor that affected P removal capacity and the product types, while temperature had certain effect at low P concentration. The dominant product was weakly adsorptive phosphorus for low P concentration at low temperature, which was substituted by Ca-P precipitate as temperature or P concentration increased. The increase of P concentration assisted both the increase of P removal potential and the formation of Ca-P precipitate to crystal DCPD.


Subject(s)
Wastewater , Water Pollutants, Chemical/analysis , Adsorption , Hydrogen-Ion Concentration , Kinetics , Phosphorus , Temperature
8.
Bioresour Technol ; 289: 121740, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31323716

ABSTRACT

Bioelectrochemically-assisted vermifilter (VBFBE) with sewage sludge as the anode fuel was constructed to accelerate composting of sewage sludge, which could increase the quality of the compost and harvest electric energy in comparison with vermicomposting and electrochemical only. Results revealed that the sludge stabilization with a higher soluble chemical oxygen demand (SCOD) and lower NH4+-H during 40 days of composting. At the composting, pH, C/N, electrical conductivity (EC) and germination index (GI) results demonstrated that the maturity degree of VBFBE4 was higher than that of other VBFBE. The VBFBE4 yielded a voltage of 1.024 V and maximum power density of 105.28 mW/m2 on 3th day. The bacteria in VBFBE4 were richer and higher in terms of diversity than those in other VBFBE, that was demonstrated that combination vermicomposting and electrochemistry could improve the sludge stabilization degree, accelerate sludge composting process and enhance composting maturity.


Subject(s)
Sewage/microbiology , Bacteria , Composting , Electricity , Electrochemical Techniques , Filtration
9.
Bioresour Technol ; 289: 121617, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31220767

ABSTRACT

Carrier aerated biofilm reactor (CABR) with nylon silk as the biofilm growth carrier was constructed to treatment of polluted surface water, which could improve the practical application in comparison with MABR process. The results show that CABR process can effectively improve the self-purification capacity of the polluted surface water, efficient removal of COD and NH3-N, making water quality achieve the level V of Environmental Quality Standards for Surface Water (GB 3838-2002, China). Modified nylon silk can alter the community structures and increase bacteria during CABR process operation. Large pore size of nylon silk leads to the formation of special biofilm structure in CABR. Extracellular polymer (EPS) and membrane fouling resistance distribution indicated that the nylon silk fouling control ability of CABR reactor is much higher than that of membrane-aerated biofilm reactors (MABR). The results show that the CABR process can effectively purify surface water and improve the practical application.


Subject(s)
Bioreactors , Water Purification , Biofilms , China , Nylons , Silk , Waste Disposal, Fluid
10.
Environ Sci Pollut Res Int ; 25(1): 771-781, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29063402

ABSTRACT

Horizontal zeolite subsurface constructed wetland system (HZCWs) and horizontal limestone subsurface constructed wetland system (HLCWs) were applied to the removal of nitrogen in lightly polluted wastewater, and the existing forms, changes, and removal mechanism of nitrogen in the constructed wetlands were analyzed. The results indicated that compared with HLCWs, HZCWs exhibited better nitrogen removal effect, and the maximum removal rates of ammonia nitrogen and total nitrogen could reach 96.97 ± 5.29 and 93.12 ± 3.35%, respectively. Besides, analysis of the removal effect on nitrogen in different existing forms on different substrate heights in the constructed wetlands showed that variation of nitrogen removal efficiency had certain regularities, which were related to the interior construction features of the wetland systems, and agreed with the regularities in the changes of the influential factors such as DO inside of the wetlands. In addition, degradation mechanism of pollutions was also analyzed, and the results indicated that the quantity of microorganisms and enzymes, including FDA, catalase, and urease, on the surface of the substrates had significant influence on the removal regularities and effects of the major pollutions in constructed wetlands.


Subject(s)
Nitrogen/chemistry , Water Pollutants, Chemical/chemistry , Wetlands , Calcium Carbonate/chemistry , Nitrogen/analysis , Waste Disposal, Fluid , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Water Purification , Zeolites/chemistry
11.
Chemosphere ; 180: 57-64, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28391153

ABSTRACT

Vermi-biofilter (VF) System could be an efficient sludge treatment unit in regard of rates and extents of total chemical oxygen demand (TCOD) removal, particularly the first 10 days earthworm-treated. This study characterized the organic matter in sludge before and after VF system treatment, with or without earthworm stage. The 60 days earthworm-treated VF system reached a TCOD removal of 10,450 mg/L, bulk DOC removal of 89.5 mg/L, and earthworm density increase from 32 g/L to 43 g/L in sludge EBOM in 60 days of VF system operation. The aromatic proteins, soluble microbial byproduct-like fluorescent compounds and carboxylic components, aliphatic components (C-H related), hydrocarbon and carbohydrate materials were identified to be principally increased by 10 days earthworm-treated and then degradation in the nest days under VF system.


Subject(s)
Filtration/instrumentation , Oligochaeta , Waste Disposal, Fluid/methods , Animals , Biological Oxygen Demand Analysis , Carbohydrates , Hydrocarbons , Proteins , Sewage/chemistry
12.
Nat Commun ; 6: 6802, 2015 Apr 14.
Article in English | MEDLINE | ID: mdl-25869033

ABSTRACT

The responses of visual cortical neurons to natural stimuli are both reliable and sparse. These properties require inhibition, yet the contribution of specific types of inhibitory neurons is not well understood. Here we demonstrate that optogenetic suppression of parvalbumin (PV)- but not somatostatin (SOM)-expressing interneurons reduces response reliability in the primary visual cortex of anaesthetized and awake mice. PV suppression leads to increases in the low firing rates and decreases in the high firing rates of cortical neurons, resulting in an overall reduction of the signal-to-noise ratio (SNR). In contrast, SOM suppression generally increases the overall firing rate for most neurons, without affecting the SNR. Further analysis reveals that PV, but not SOM, suppression impairs neural discrimination of natural stimuli. Together, these results reveal a critical role for PV interneurons in the formation of reliable visual cortical representations of natural stimuli.


Subject(s)
Evoked Potentials, Visual/genetics , Interneurons/metabolism , Neural Inhibition/genetics , Parvalbumins/genetics , Somatostatin/genetics , Visual Cortex/metabolism , Anesthesia , Animals , Gene Expression , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Interneurons/cytology , Mice , Mice, Transgenic , Optogenetics , Parvalbumins/metabolism , Photic Stimulation , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Reproducibility of Results , Rhodopsins, Microbial/genetics , Rhodopsins, Microbial/metabolism , Signal-To-Noise Ratio , Somatostatin/metabolism , Synaptic Transmission/genetics , Visual Cortex/cytology , Wakefulness/physiology
13.
J Environ Sci (China) ; 25(1): 59-68, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23586300

ABSTRACT

To find a simple and economical way for treating the domestic wastewater in small counties and towns, a process combining chemically enhanced primary treatment and a trickling filter (CEPT-TF, representing the physical and biological effects) was constructed and operated in laboratory conditions. The characteristic behaviors of dissolved organic matter in raw wastewater and effluents were examined during steady-state operation. Experimental results showed that the process of CEPT and TF in series was beneficial for the removal of hydrophobic and hydrophilic organics. Specially, the hydrophobic and aromatic materials could be preferentially removed in the CEPT unit, and the hydrophilic fraction in the TF. Structural changes of the organic fractions during the operation of the different units were also characterized via spectrum analysis.


Subject(s)
Filtration/methods , Organic Chemicals/isolation & purification , Waste Disposal, Fluid/methods , Wastewater
14.
Water Sci Technol ; 65(9): 1599-605, 2012.
Article in English | MEDLINE | ID: mdl-22508122

ABSTRACT

More and more research effort has been put into the development of affordable and high-efficiency wastewater reclamation technology for small communities. In this study, an integrated chemically enhanced primary treatment (CEPT), trickling filter (TF) and ultrafiltration (UF) process was developed with success. Coagulant produced from fly ash was used to enhance primary treatment, while trickling filter packed with coal cinder through four-layer structure without aeration was employed for further removal of COD and ammonium-nitrogen from the CEPT effluent. 95 and 88% removal of COD and ammonium were achieved, while total phosphorus (TP) and suspended solid (SS) were found to be removed completely at a coagulant dosage of 2.5 mL/L in the CEPT-TF-UF system. The product water can meet the standard of Reuse of Recycling Water for Urban Water Quality Standard for Urban Miscellaneous Water Consumption (GB/T 18920-2002, China).


Subject(s)
Filtration/instrumentation , Filtration/methods , Recycling , Waste Disposal, Fluid/methods , Coal , Coal Ash , Membranes, Artificial , Nitrogen/chemistry , Quaternary Ammonium Compounds/chemistry , Seasons , Time Factors , Water Purification
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