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1.
J Hazard Mater ; 469: 133940, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38457979

ABSTRACT

Glutaraldehyde-Didecyldimethylammonium bromides (GDs) has been frequently and widely employed in livestock and poultry breeding farms to avoid epidemics such as African swine fever, but its long-term effect on the active sludge microorganisms of the receiving wastewater treatment plant was keep unclear. Four simulation systems were built here to explore the performance of aerobic activated sludge with the long-term exposure of GDs and its mechanism by analyzing water qualities, resistance genes, extracellular polymeric substances and microbial community structure. The results showed that the removal rates of CODCr and ammonia nitrogen decreased with the exposure concentration of GDs increasing. It is worth noting that long-term exposure to GDs can induce the horizontal transfer and coordinated expression of a large number of resistance genes, such as qacE, sul1, tetx, and int1, in drug-resistant microorganisms. Additionally, it promotes the secretion of more extracellular proteins, including arginine, forming a "barrier-like" protection. Therefore, long-term exposure to disinfectants can alter the treatment capacity of activated sludge receiving systems, and the abundance of resistance genes generated through horizontal transfer and coordinated expression by drug-resistant microorganisms does pose a significant threat to ecosystems and health. It is recommended to develop effective pretreatment methods to eliminate disinfectants.


Subject(s)
African Swine Fever , Disinfectants , Animals , Swine , Sewage/chemistry , Extracellular Polymeric Substance Matrix , Waste Disposal, Fluid/methods , Disinfectants/toxicity , Ecosystem
2.
Water Res ; 253: 120141, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38377919

ABSTRACT

Anaerobic ammonium oxidation (ANAMMOX)-mediated system is a cost-effective green nitrogen removal process. However, there are few examples of successful application of this advanced wastewater denitrification process in wastewater treatment plants, and the understanding of how to implement anaerobic ammonia oxidation process in full-scale is still limited. In this study, it was found that the abundance of anaerobic ammonia-oxidizing bacteria (AnAOB) in the two livestock wastewater plants named J1 and J2, respectively, showed diametrically opposed trends of waxing and waning with time. The microbial communities of the activated sludge in the two plants at different time were sampled and analyzed by high-throughput sequencing of 16S rRNA genes. Structural equation models (SEMs) were used to reveal the key factors affecting the realization of the ANAMMOX. Changes in the concentration of dissolved oxygen and C/N had a significant effect on the relative abundance of anaerobic ammonia oxidation bacteria (AnAOB). The low concentration of DO (0.2∼0.5 mg/L) could inhibit the activity of nitrifying bacteria (NOB) to achieve partial oxidation of ammonia nitrogen and provide sufficient substrate for the growth of AnAOB, similar to the CANON (Completely Autotrophic Nitrogen removal Over Nitrite). Unlike CANON, heterotrophic denitrification is also a particularly critical part of the livestock wastewater treatment, and a suitable C/N of about 0.6 could reduce the competition risk of heterotrophic microorganisms to AnAOB and ensure a good ecological niche for AnAOB. Based on the results of 16S rRNA and microbial co-occurrence networks, it was discovered that microorganisms in the sludge not only had a richer network interaction, but also achieved a mutually beneficial symbiotic interaction network among denitrifying bacteria (Pseudomonas sp., Terrimonas sp., Dokdonella sp.), AnAOB (Candidatus Brocadia sp.) at DO of 0.2∼0.5 mg/L and C/N of 0.6. Among the top 20 in abundance of genus level, AnAOB had a high relative abundance of 27.66%, followed by denitrifying bacteria of 3.67%, AOB of 0.64% and NOB of 0.26%, which is an essential indicator for the emergence of an AnAOB-dominated nitrogen removal cycle. In conclusion, this study highlights the importance of dissolved oxygen and C/N regulation by analyzing the mechanism of ANAMMOX sludge extinction and growth in two plants under anthropogenic regulation of AnAOB in full-scale wastewater treatment systems.


Subject(s)
Wastewater , Water Purification , Animals , Sewage , Ammonia , Livestock , Anaerobic Ammonia Oxidation , RNA, Ribosomal, 16S , Bioreactors/microbiology , Bacteria/genetics , Agriculture , Nitrogen , Oxygen , Oxidation-Reduction , Denitrification
3.
Front Psychol ; 14: 1124477, 2023.
Article in English | MEDLINE | ID: mdl-38022958

ABSTRACT

Introduction: Memory and discourse production are closely related in healthy populations. A few studies in people with amnestic mild cognitive impairment and people with dementia (PWD) suggested similar links, although empirical evidence is insufficient to inform emerging intervention design and natural language processing research. Fine-grained discourse assessment is needed to understand their complex relationship in PWD. Methods: Spoken samples from 104 PWD were elicited using personal narrative and sequential picture description and assessed using Main Concept Analysis and other content-based analytic methods. Discourse and memory performance data were analyzed in bivariate correlation and linear multiple regression models to determine the relationship between discourse production and episodic autobiographical memory and verbal short-term memory (vSTM). Results: Global coherence was a significant predictor of episodic autobiographical memory, explaining over half of the variance. Both episodic autobiographical memory and vSTM were positively correlated with global coherence and informativeness, and negatively with empty speech indices. Discussion: Coherence in personal narrative may be supported by episodic autobiographical memory and vice versa, suggesting potential mechanism of interventions targeting personhood through conversation. Indices of global coherence, informativeness, and empty speech can be used as markers of memory functions in PWD.

4.
Clin Interv Aging ; 17: 97-116, 2022.
Article in English | MEDLINE | ID: mdl-35173425

ABSTRACT

PURPOSE: This feasibility and pilot study aimed to develop and field-test a 14-session virtual Cognitive Stimulation Therapy (vCST) programme for people living with dementia, developed as a result of services moving online during the COVID-19 pandemic. METHODS: The vCST protocol was developed using the existing group CST manual, through stakeholder consultation with people living with dementia, caregivers, CST group facilitators and dementia service managers. This protocol was then field-tested with 10 groups of people living with dementia in the Brazil, China (Hong Kong), India, Ireland and the UK, and feedback on the protocol was gathered from 14 facilitators. RESULTS: Field testing in five countries indicated acceptability to group facilitators and participants. Feedback from these groups was used to refine the developed protocol. The final vCST protocol is proposed, including session materials for delivery of CST over videoconferencing and a framework for offering CST virtually in global settings. CONCLUSION: vCST is a feasible online intervention for many people living with dementia. We recommend that it is offered to those unable to access traditional in-person CST for health reasons, lack of transport or COVID-19 restrictions. Further research is needed to explore if participant outcomes are comparable to in-person CST groups.


Subject(s)
COVID-19 , Dementia , Cognition , Dementia/psychology , Dementia/therapy , Humans , Pandemics , Pilot Projects , Quality of Life , SARS-CoV-2
5.
BMJ Open ; 11(8): e047560, 2021 08 17.
Article in English | MEDLINE | ID: mdl-34404702

ABSTRACT

INTRODUCTION: As the largest and most rapidly ageing population, Chinese people are now the major driver of the continued growth in dementia prevalence globally. The need for evidence-based interventions in Chinese communities is urgent. Although a wide range of pharmacological and non-pharmacological interventions for dementia have been trialled in Chinese populations, the evidence has not been systematically synthesised. This systematic review and meta-analysis aims to map out the interventions for people living with dementia and their carers in Chinese communities worldwide and compare the effectiveness of these interventions. METHODS AND ANALYSIS: This protocol followed the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols checklist. We will search Chinese (China National Knowledge Infrastructure, WanFang DATA) and English bibliographical databases (MEDLINE, EMBASE, PsycINFO, CINAHL Plus, Global Health, WHO Global Index Medicus, Virtual Health Library, Cochrane CENTRAL, Social Care Online, BASE, MODelling Outcome and cost impacts of interventions for DEMentia (MODEM) Toolkit, Cochrane Database of Systematic Reviews), complemented by hand searching of reference lists. We will include studies evaluating the effectiveness of interventions for dementia or mild cognitive impairment in Chinese populations, using a randomised controlled trial design, and published between January 2008 and June 2020. We will use a standardised form to extract data and Version 2 of the Cochrane risk-of-bias tool for randomised trials to assess the risk of bias of the included studies. Collected data will be fully interpreted with narrative synthesis and analysed using pairwise and network meta-analyses to pool intervention effects where sufficient information is available. We will perform subgroup analysis and meta-regression to explore potential reasons for heterogeneity. ETHICS AND DISSEMINATION: No formal ethics approval is required for this protocol. The findings will facilitate the development of studies on interventions for dementia and timely inform dementia policymaking and practice. Planned dissemination channels include peer-reviewed publications, conference presentations, public events and websites. PROSPERO REGISTRATION NUMBER: CRD42019134135.


Subject(s)
Caregivers , Dementia , China , Dementia/therapy , Humans , Meta-Analysis as Topic , Randomized Controlled Trials as Topic , Systematic Reviews as Topic
7.
J Environ Manage ; 257: 109968, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31868637

ABSTRACT

The removal of trace antibiotics from the aquatic environment has received great interest. In this investigation, NaOH activated graphite felt (NaOH-GF) was characterized by multiple-methods, including scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle, linear sweep voltammetry (LSV) and electron paramagnetic resonance (EPR). The NaOH-GF was then used as the cathode in the electro-Fenton process for oxytetracycline (OTC) degradation, the experiment was carried out in an undivided and light-proof beaker with a Pt anode and a NaOH-GF cathode at pH 3. The results showed that the modification with NaOH enhanced the antibiotics degradation efficiency of graphite felt by increasing the oxygen reduction capacity and hydroxyl radicals yielding rate. Complete OTC removal was achieved at 5.17 mA cm-2 after 40, 60 and 90 s with initial OTC concentration of 22, 44, and 66 µM, respectively. With an initial OTC concentration of 44 µM, after 30 min the removal rates of chemical oxygen demand (COD) by Raw-GF and NaOH-GF were 59.18% and 83.75%, respectively. The proposed degradation mechanism of OTC was an EF process, which consisted of hydroxylation, secondary alcohol oxidation, demethylation, decarbonylation, dehydration and deamination. This study demonstrates that NaOH activated GF cathode possesses high degradation capacity and good stability. It provides insight into the removal of non-biodegradable antibiotics and may shed light on future to its practical application.


Subject(s)
Graphite , Oxytetracycline , Water Pollutants, Chemical , Electrodes , Hydrogen Peroxide , Iron , Kinetics , Oxidation-Reduction
8.
Mem Cognit ; 46(5): 809-825, 2018 07.
Article in English | MEDLINE | ID: mdl-29383599

ABSTRACT

Research examining object identity and location processing in visuo-spatial working memory (VSWM) has yielded inconsistent results on whether age differences exist in VSWM. The present study investigated whether these inconsistencies may stem from age-related differences in VSWM sub-processes, and whether processing of component VSWM information can be facilitated. In two experiments, younger and older adults studied 5 × 5 grids containing five objects in separate locations. In a continuous recognition paradigm, participants were tested on memory for object identity, location, or identity and location information combined. Spatial and categorical relationships were manipulated within grids to provide trial-level facilitation. In Experiment 1, randomizing trial types (location, identity, combination) assured that participants could not predict the information that would be queried. In Experiment 2, blocking trials by type encouraged strategic processing. Thus, we manipulated the nature of the task through object categorical relationship and spatial organization, and trial blocking. Our findings support age-related declines in VSWM. Additionally, grid organizations (categorical and spatial relationships), and trial blocking differentially affected younger and older adults. Younger adults used spatial organizations more effectively whereas older adults demonstrated an association bias. Our finding also suggests that older adults may be less efficient than younger adults in strategically engaging information processing.


Subject(s)
Aging/physiology , Memory, Short-Term/physiology , Pattern Recognition, Visual/physiology , Recognition, Psychology/physiology , Space Perception/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult
9.
Huan Jing Ke Xue ; 30(3): 875-81, 2009 Mar 15.
Article in Chinese | MEDLINE | ID: mdl-19432344

ABSTRACT

Samples of sediment, overlying water, pore water, and benthic invertebrate were collected at 13 stations along a typical municipal polluted river in the Pearl River Delta. The samples were analyzed to study relationships between acid volatile sulfide (AVS) versus Cr(III) and Cr(VI) in sediment, overlying water, and pore water as well as Cr in Limnodrilus sp.. Based on the "Cr hypothesis", the relationship between AVS and bioavailability of Cr in heavily polluted areas was explored to extend the utility of AVS measurements as sediment assessments. The mean value of total Cr in sediment was 329.57 mg/kg, which was 9.4 times of background value (35 mg/kg). The result indicated that the study area has been seriously polluted by Cr. The concentrations of Cr(VI) in sediment and overlying water were low, indicating that most of Cr was in the form of Cr(III). In the study area, the value of AVS was relatively high with an average value of 650.38 mg/kg, while Cr in the pore water was low with the average of 68.42 microg/L. Cr(VI) in the pore water was below the detection limit except at Z1 station. The range of Cr concentrations in Limnodrilus sp. was from 12.46 mg/kg to 38.99 mg/kg of dried weight, with the average of 25.85 mg/kg, which was higher than other similar results in the literature. The result showed that the amount of Cr accumulation in Limnodrilus sp. was significant. A further analysis showed a significant correlation between Cr in Limnodrilus sp. and Cr in the pore water (r = 0.614, p < 0.05). Since most of Cr in pore water was in the form of Cr(III), the toxicity of Cr(III) in pore water to organism can not be neglected in the heavily polluted river.


Subject(s)
Chromium/analysis , Geologic Sediments/chemistry , Sulfides/analysis , Water Pollutants, Chemical/analysis , Acids/chemistry , Animals , China , Cities , Environmental Monitoring , Fresh Water/analysis , Invertebrates/metabolism , Rivers/chemistry , Volatilization
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