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1.
Clin Microbiol Rev ; 37(2): e0016123, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38634634

ABSTRACT

SUMMARYLincosamides constitute an important class of antibiotics used against a wide range of pathogens, including methicillin-resistant Staphylococcus aureus. However, due to the misuse of lincosamide and co-selection pressure, the resistance to lincosamide has become a serious concern. It is urgently needed to carefully understand the phenomenon and mechanism of lincosamide resistance to effectively prevent and control lincosamide resistance. To date, six mobile lincosamide resistance classes, including lnu, cfr, erm, vga, lsa, and sal, have been identified. These lincosamide resistance genes are frequently found on mobile genetic elements (MGEs), such as plasmids, transposons, integrative and conjugative elements, genomic islands, and prophages. Additionally, MGEs harbor the genes that confer resistance not only to antimicrobial agents of other classes but also to metals and biocides. The ultimate purpose of discovering and summarizing bacterial resistance is to prevent, control, and combat resistance effectively. This review highlights four promising strategies, including chemical modification of antibiotics, the development of antimicrobial peptides, the initiation of bacterial self-destruct program, and antimicrobial stewardship, to fight against resistance and safeguard global health.


Subject(s)
Anti-Bacterial Agents , Drug Resistance, Bacterial , Lincosamides , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Lincosamides/pharmacology , Lincosamides/therapeutic use , Humans , Drug Resistance, Bacterial/genetics , Bacteria/drug effects , Bacteria/genetics
2.
Small ; : e2402726, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38651509

ABSTRACT

Heterogeneous catalysts have attracted extensive attention among various emerging catalysts for their exceptional oxygen evolution reaction (OER) capabilities, outperforming their single-component counterparts. Nonetheless, the synthesis of heterogeneous materials with predictable, precise, and facile control remains a formidable challenge. Herein, a novel strategy involving the decoration of catalysts with CeO2 is introduced to concurrently engineer heterogeneous interfaces and adjust phase composition, thereby enhancing OER performance. Theoretical calculations suggest that the presence of ceria reduces the free energy barrier for the conversion of nitrides into metals. Supporting this, the experimental findings reveal that the incorporation of rare earth oxides enables the controlled phase transition from nitride into metal, with the proportion adjustable by varying the amount of added rare earth. Thanks to the role of CeO2 decoration in promoting the reaction kinetics and fostering the formation of the genuine active phase, the optimized Ni3FeN/Ni3Fe/CeO2-5% nanoparticles heterostructure catalyst exhibits outstanding OER activity, achieving an overpotential of just 249 mV at 10 mA cm-2. This approach offers fresh perspectives for the conception of highly efficient heterogeneous OER catalysts, contributing a strategic avenue for advanced catalytic design in the field of energy conversion.

3.
BMC Public Health ; 24(1): 1760, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956571

ABSTRACT

OBJECTIVE: Adverse childhood experiences (ACEs) have been associated with a range of adverse health outcomes, with pain being potentially one of them. This population-based cross-sectional study aimed to investigate the associations between Adverse Childhood Experiences (ACEs) and pain in Chinese adults and evaluate whether physical activity and demographic and socioeconomic characteristics modify this associations. METHODS: Cross-sectional data from the China Health and Retirement Longitudinal Study (CHARLS), were utilized in this study. A total of 9923 respondents with information on 12 ACE indicators and 15 self-reported body pains were included. Logistic regression models were used to assess associations of the ACEs and pain. Modification of the associations by physical activity, demographic and socioeconomic characteristics was assessed by stratified analyses and tests for interaction. RESULTS: Among the 9923 individuals included in the primary analyses, 5098 (51.4%) males and the mean (SD) age was 61.18 (10·.44) years. Compared with individuals with 0 ACEs, those who with ≥ 5 ACEs had increased risk of single pains and multiple pain. A dose-response association was found between the number of ACEs and the risk of pain (e.g. neck pain for ≥ 5 ACEs vs. none: OR, 1.107; 95% CI, 0.903-1.356; p < 0.001 for trend). In the associations of each body pain with each ACE indicator, most ACE indicators were associated with an increased risk of pain. In addition, physical activity, sociodemographic and socioeconomic characteristics, such as age, sex, educational level, area of residence, childhood economic hardship, did not demonstrate a significant modify on the associations between ACEs and pain. CONCLUSIONS: These findings indicate that cumulative ACE exposure is associated with increased odds of self-reported pain in Chinese adults, regardless of adult physical activity, sociodemographic and socioeconomic characteristics.


Subject(s)
Adverse Childhood Experiences , Pain , Humans , Male , Female , China/epidemiology , Longitudinal Studies , Adverse Childhood Experiences/statistics & numerical data , Middle Aged , Cross-Sectional Studies , Aged , Pain/epidemiology , Exercise , Socioeconomic Factors , Risk Factors
4.
Opt Express ; 31(20): 33141-33149, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859101

ABSTRACT

AlxGa1-xAsySb1-y grown lattice-matched to InP has attracted significant research interest as a material for low noise, high sensitivity avalanche photodiodes (APDs) due to its very dissimilar electron and hole ionization coefficients, especially at low electric fields. All work reported to date has been on Al concentrations of x = 0.85 or higher. This work demonstrates that much lower excess noise (F = 2.4) at a very high multiplication of 90 can be obtained in thick Al0.75Ga0.25As0.56Sb0.44 grown on InP substrates. This is the lowest excess noise that has been reported in any III-V APD operating at room temperature. The impact ionization coefficients for both electrons and holes are determined over a wide electric field range (up to 650 kV/cm) from avalanche multiplication measurements undertaken on complementary p-i-n and n-i-p diode structures. While these ionization coefficients can fit the experimental multiplication over three orders of magnitude, the measured excess noise is significantly lower than that expected from the ß/α ratio and the conventional local McIntyre noise theory. These results are of importance not just for the design of APDs but other high field devices, such as transistors using this material.

5.
Int Wound J ; 20(10): 4300-4307, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37493021

ABSTRACT

By conducting a meta-analysis of relevant clinical studies on the treatment of advanced gastric cancer (GC) using laparoscopic and open surgeries, we aimed to evaluate the impact of these two surgical approaches on postoperative surgical site infections (SSIs) in patients with advanced GC. We aimed to provide evidence-based support for preventing SSIs in postoperative patients with advanced GC. From database establishment until May 2023, we systematically searched PubMed, Cochrane Library, MEDLINE, Embase, China National Knowledge Infrastructure, and Wanfang Data databases for relevant studies comparing laparoscopic and open surgeries for the treatment of advanced GC. Two researchers independently performed the literature screening and data extraction based on predefined inclusion and exclusion criteria. The meta-analysis was conducted using STATA 17.0. Twenty articles involving 3084 patients met the inclusion criteria, including 1462 patients in the laparoscopic group and 1622 cases in the open surgery group. The meta-analysis results revealed that the incidence of postoperative SSIs was significantly lower in the laparoscopic group than in the open surgery group (odds ratio = 0.341, 95% confidence interval: 0.219-0.532, p < 0.001). The current evidence indicates that laparoscopic radical gastrectomy can significantly reduce the incidence of postoperative site infections in patients with advanced GC.


Subject(s)
Laparoscopy , Stomach Neoplasms , Humans , Surgical Wound Infection/etiology , Surgical Wound Infection/prevention & control , Surgical Wound Infection/surgery , Stomach Neoplasms/surgery , Gastrectomy/adverse effects , Gastrectomy/methods , Laparoscopy/adverse effects , Laparoscopy/methods , China/epidemiology
6.
Ecotoxicol Environ Saf ; 211: 111925, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33465627

ABSTRACT

Black soldier fly larvae (BSFL) have great potential in livestock manure disposal. However, the changes in metal speciation, microbial communities, potential pathogens during the manure transformation process by BSFL is still largely uncharacterized, as well as the underlying metal tolerance mechanism of larval gut microbiome. Here we used BSFL to convert pig manure (PM) into larval feces (BF), and investigated the metal and microbial changes in the conversion process. Physicochemical parameters (e.g. pH, electrical conductivity, total nitrogen, total phosphorus and total potassium) in PM were significantly altered compared to BF. After conversion, less than 10% of Cu and Zn were accumulated in larval bodies. The bioavailable fraction of Cu (88.3%-86.2%) and Zn (80.6%-82.3%) occupied as the primary form in PM and BF. Genera Enterococcus, Clostridium_sensu_stricto_1, Terrisporobacter and Romboutsia were substantially enriched in the final BSFL gut (GF) compared with initial gut (GI). BSFL transformation substantially reduced pathogen abundances (decreased by 89%) derived from pig manure. Functional genes involved in metal homeostasis and resistance (e.g. CutC, pcoC, cusR, zurR and zntB) were obviously strengthened (by 2.3-7.7 folds) in GF than in GI, which might partly explain the metal tolerance ability of BSFL during the livestock manure transformation process.


Subject(s)
Biotransformation/physiology , Diptera/physiology , Metals/metabolism , Animals , Feces , Gastrointestinal Microbiome , Larva , Livestock , Manure , Nitrogen , Swine
7.
J Environ Sci (China) ; 107: 150-159, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34412778

ABSTRACT

The black soldier fly larvae (BSFL) have been successfully applied to treat various organic wastes. However, the impacts of heavy metals on antibiotic resistance in the BSFL guts are poorly understood. Here, we investigated the effect of copper (exposure concentrations of 0, 100 and 800 mg/kg) on the antibiotic and metal resistance profiles in BSFL guts. A total of 83 antibiotic resistance genes (ARGs), 18 mobile genetic elements (MGEs) and 6 metal resistance genes (MRGs) were observed in larval gut samples. Exposure to Cu remarkably reduced the diversity of ARGs and MGEs, but significantly enhanced the abundances of gut-associated ARGs and MRGs. The levels of MRGs copA, czcA and pbrT were dramatically strengthened after Cu exposure as compared with CK (increased by 2.8-13.5 times). Genera Enterococcus acted as the most predominant potential host of multiple ARG, MGE and MRG subtypes. Meanwhile, high exposure to Cu aggravated the enrichment of potential pathogens in BSFL guts, especially for Escherichia, Enterococcus and Salmonella species. The mantel test and procrustes analysis revealed that the gut microbial communities could be a key determinant for antibiotic and metal resistance. However, no significant positive links were observed between MGEs and ARGs or MRGs, possibly suggesting that MGEs did not play a crucial role in shaping the ARGs or MRGs in BSFL guts under the stress of Cu. These findings extend our understanding on the impact of heavy metals on the gut-associated antibiotic and metal resistome of BSFL.


Subject(s)
Diptera , Metals, Heavy , Animals , Copper/toxicity , Drug Resistance, Microbial/genetics , Genes, Bacterial , Incidence , Larva , Metals, Heavy/toxicity
8.
Ecotoxicol Environ Saf ; 192: 110323, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32066008

ABSTRACT

The black soldier fly larvae (BSFL) have become a promising candidate for waste disposal and are an ideal feed source for animal nutrition. The uptake of heavy metals could influence the growth of BSFL, but the effects of heavy metal pressures on the gut microbiota of BSFL are largely uncharacterized. Here, we examine the influences of Cu and Cd on the growth and gut microbiota of BSFL as well as the distribution of accumulated heavy metals in the larvae and their feces. Exposure to Cu (from 100 to 800 mg/kg) and Cd (from 10 to 80 mg/kg) did not significantly inhibit the weight gain of BSFL. With elevated exposure doses, the contents of both Cu and Cd accumulated in the bodies and feces of BSFL were remarkably increased. In the BSFL feces, Cu mainly existed as residues, while Cd mainly existed as either water-soluble states (in the low-exposure groups) or residues (in the high-exposure groups). Cd was more readily enriched (47.1%-91.3%) than Cu (<30%) in vivo. More importantly, exposure to Cu and Cd remarkably altered the gut microbiota of BSFL, particularly in the phyla Proteobacteria, Firmicutes and Bacteroidetes. High exposure to the metals (i.e., Cu-800 and Cd-80 groups) substantially decreased the abundances of most of the dominant families, but significantly stimulated the enrichment of Brucellaceae, Enterobacteriaceae, Alcaligenaceae, Campylobacteraceae, and Enterococcaceae. Moreover, the bacterial diversity in the BSFL gut was significantly reduced following high exposure to the metals. These results may fill a gap in our knowledge of the effects of heavy metals on the intestinal microbiome of BSFL.


Subject(s)
Diptera/drug effects , Gastrointestinal Microbiome/drug effects , Metals, Heavy/pharmacology , Animals , Bacteria/isolation & purification , Bioaccumulation , Cadmium/pharmacokinetics , Cadmium/pharmacology , Copper/pharmacokinetics , Copper/pharmacology , Diptera/growth & development , Diptera/metabolism , Diptera/microbiology , Feces/chemistry , Larva/drug effects , Larva/growth & development , Larva/metabolism , Larva/microbiology , Metals, Heavy/pharmacokinetics , Refuse Disposal
9.
Biochim Biophys Acta Mol Basis Dis ; 1864(7): 2481-2494, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29654945

ABSTRACT

Diabetes-induced endothelial cell (EC) dysfunction and neovascularization impairment constitute vascular complications with limited treatment regimens. Transcription factor FOXO1 is a key angiogenic regulator and plays a pathologic role in progression of diabetes. The present study was designed to determine the involvement of FOXO1 in impaired EC function and post-ischemic neovascularization in diabetes and investigate underlying mechanisms. We found that FOXO1-selective inhibitor AS1842856 improved blood flow recovery and capillary density in ischemic hindlimb, and rescued the delay of wound closure with a concomitant augmentation of mean perfusion rate in diabetic mice. In vitro, treatment with AS1842856 or FOXO1 siRNA abrogated high glucose-induced apoptosis and ameliorated capillary tube formation in human umbilical vein endothelial cells (HUVECs). FOXO1 inhibition relieved alterations in mitochondrial networks and significantly suppressed the overproduction of mitochondrial reactive oxygen species (mtROS) induced by high glucose in ECs. Expression of dynamin-related protein-1 (Drp1) and phosphorylation at Ser616, a protein required for mitochondrial fission, were enhanced by hyperglycemia, which could be neutralized by FOXO1 inhibition. Moreover, the transcription of Rho-associated coiled-coil containing protein kinase 1 (ROCK1), which phosphorylates Drp1 at Ser616, was shown by luciferase assay to be directly regulated by FOXO1. These findings suggested that FOXO1 is critical to preserve mitochondrial quantity and function in ECs, and FOXO1 may serve as a therapeutic target for microvascular complications of diabetes.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Diabetic Angiopathies/metabolism , Dynamins/metabolism , Endothelium, Vascular/metabolism , Forkhead Box Protein O1/metabolism , Mitochondria/metabolism , Mitochondrial Dynamics , Neovascularization, Physiologic , rho-Associated Kinases/metabolism , Animals , Diabetes Mellitus, Experimental/pathology , Diabetic Angiopathies/pathology , Endothelium, Vascular/pathology , Human Umbilical Vein Endothelial Cells , Humans , Male , Mice , Mitochondria/pathology
10.
Opt Express ; 24(21): 24242-24247, 2016 Oct 17.
Article in English | MEDLINE | ID: mdl-27828254

ABSTRACT

Increasing reliance on the Internet places greater and greater demands for high-speed optical communication systems. Increasing their data transfer rate allows more data to be transferred over existing links. With optical receivers being essential to all optical links, bandwidth performance of key components in receivers, such as avalanche photodiodes (APDs), must be improved. The APDs rely on In0.53Ga0.47As (grown lattice-matched to InP substrates) to efficiently absorb and detect the optical signals with 1310 or 1550 nm wavelength, the optimal wavelengths of operation for these optical links. Thus developing InP-compatible APDs with high gain-bandwidth product (GBP) is important to the overall effort of increasing optical links' data transfer rate. Here we demonstrate a novel InGaAs/AlGaAsSb APD, grown on an InP substrate, with a GBP of 424 GHz, the highest value reported for InP-compatible APDs, which is clearly applicable to future optical communication systems at or above 10 Gb/s. The data reported in this article are available from the figshare digital repository (https://dx.doi.org/10.15131/shef. DATA: 3827460.v1).

11.
Front Psychol ; 15: 1387677, 2024.
Article in English | MEDLINE | ID: mdl-39015326

ABSTRACT

Objective: To explore the mediating roles of activities of daily living (ADL) and economic burden of diseases in the relationship between chronic diseases and depressive symptoms of older adults. Methods: The data were sourced from China Health and Retirement Longitudinal Study (CHARLS). The number of chronic diseases, ADL, out-of-pocket medical expenses and the Center for Epidemiological Studies Depression Scale (CES-D) were selected as measuring indexes. Mediation analysis was conducted to explore the potential mediating roles of ADL and economic burden of diseases in the association between chronic diseases and depressive symptoms. Results: The number of chronic diseases, ADL, economic burden of diseases and depressive symptoms of older adults were significantly correlated with each other. ADL and economic burden of diseases individually mediated the relationship between the number of chronic diseases and depressive symptoms, accounting for 31.460% and 5.471% of the total effect, respectively. Additionally, ADL and economic burden of diseases demonstrated a chain mediating effect in this relationship, contributing to 0.759% of the total effect. Conclusion: The chain-mediated model effectively elucidated the mediating roles of ADL and economic burden of diseases in the association between chronic diseases and depressive symptoms among older adults. The study underscores the need for policymakers to focus attentively on the mental health of older adults with chronic diseases. Enhancing the capacity for ADL and strengthening social security to mitigate the economic burden of diseases are recommended strategies to alleviate depressive symptoms in older adults.

12.
J Hazard Mater ; 471: 134324, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38640666

ABSTRACT

In recent years, aquaculture has expanded rapidly to address food scarcity and provides high-quality aquatic products. However, this growth has led to the release of significant effluents, containing emerging contaminants like antibiotics, microplastics (MPs), and antibiotic resistance genes (ARGs). This study investigated the occurrence and interactions of these pollutants in aquaculture environment. Combined pollutants, such as MPs and coexisting adsorbents, were widespread and could include antibiotics, heavy metals, resistance genes, and pathogens. Elevated levels of chemical pollutants on MPs could lead to the emergence of resistance genes under selective pressure, facilitated by bacterial communities and horizontal gene transfer (HGT). MPs acted as vectors, transferring pollutants into the food web. Various technologies, including membrane technology, coagulation, and advanced oxidation, have been trialed for pollutants removal, each with its benefits and drawbacks. Future research should focus on ecologically friendly treatment technologies for emerging contaminants in aquaculture wastewater. This review provided insights into understanding and addressing newly developing toxins, aiming to develop integrated systems for effective aquaculture wastewater treatment.


Subject(s)
Anti-Bacterial Agents , Aquaculture , Microplastics , Water Pollutants, Chemical , Microplastics/toxicity , Water Pollutants, Chemical/analysis , Drug Resistance, Microbial/genetics , Gene Transfer, Horizontal , Wastewater/chemistry
13.
Adv Sci (Weinh) ; : e2404404, 2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38973215

ABSTRACT

Drawing inspiration from the jumping mechanisms of insects (e.g., click beetles), bistable structures can convert slow deformations of soft actuating material into fast jumping motions (i.e., power amplification). However, bistable jumpers often encounter large energy barriers for energy release/re-storage, posing a challenge in achieving multimodal (i.e., height/distance) and continuous jumps at the insect scale (body length under 20 mm). Here, a new offset-buckling bistable design is introduced that features antisymmetric equilibrium states and tunable energy barriers. Leveraging this design, a Boundary Actuation Tunable Energy-barrier (BATE) jumper (body length down to 15 mm) is developed, and transform BATE jumper from height-jump mode (up to 12.7 body lengths) to distance-jump mode (up to 20 body lengths). BATE jumpers can perform agile continuous jumping (within 300 ms for energy release/re-storage times) and real-time status detection is further demonstrated. This insect-level performance of the proposed BATE jumper showcases its potential toward future applications in exploration, search, and rescue.

14.
Environ Pollut ; 346: 123682, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38428788

ABSTRACT

Microplastics (MPs) in soil can influence CO2 dynamics by altering organic carbon (OC) and microbial composition. Nevertheless, the fluctuation of CO2 response attributed to MPs in mangrove sediments is unclear. This study explores the impact of micro-sized polypropylene (mPP) particles on the carbon dynamics of intertidal mangrove sediments. In the high-tide level sediment, after 28 days, the cumulative CO2 levels for varying mPP dosages were as follows: 496.86 ± 2.07, 430.38 ± 3.84 and 447.09 ± 1.72 mg kg-1 for 0.1%, 1% and 10% (w/w) mPP, respectively. The CO2 emissions were found to be increased with a 0.1% (w/w) mPP level and decreased with 1% and 10% (w/w) mPP at high-tide level sediment, suggesting a tide level-specific dose dependence of the CO2 emission pattern in mangrove sediments. Overall, results indicated that the presence of mPP in mangrove sediments would potentially affect intertidal total CO2 storage under given experimental conditions.


Subject(s)
Microplastics , Polypropylenes , Plastics , Carbon Dioxide , Wetlands , Geologic Sediments
15.
Environ Pollut ; 351: 124115, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38718963

ABSTRACT

Composting has emerged as a suitable method to convert or transform organic waste including manure, green waste, and food waste into valuable products with several advantages, such as high efficiency, cost feasibility, and being environmentally friendly. However, volatile organic compounds (VOCs), mainly malodorous gases, are the major concern and challenges to overcome in facilitating composting. Ammonia (NH3) and volatile sulfur compounds (VSCs), including hydrogen sulfide (H2S), and methyl mercaptan (CH4S), primarily contributed to the malodorous gases emission during the entire composting process due to their low olfactory threshold. These compounds are mainly emitted at the thermophilic phase, accounting for over 70% of total gas emissions during the whole process, whereas methane (CH4) and nitrous oxide (N2O) are commonly detected during the mesophilic and cooling phases. Therefore, the human health risk assessment of malodorous gases using various indexes such as ECi (maximum exposure concentration for an individual volatile compound EC), HR (non-carcinogenic risk), and CR (carcinogenic risk) has been evaluated and discussed. Also, several strategies such as maintaining optimal operating conditions, and adding bulking agents and additives (e.g., biochar and zeolite) to reduce malodorous emissions have been pointed out and highlighted. Biochar has specific adsorption properties such as high surface area and high porosity and contains various functional groups that can adsorb up to 60%-70% of malodorous gases emitted from composting. Notably, biofiltration emerged as a resilient and cost-effective technique, achieving up to 90% reduction in malodorous gases at the end-of-pipe. This study offers a comprehensive insight into the characterization of malodorous emissions during composting. Additionally, it emphasizes the need to address these issues on a larger scale and provides a promising outlook for future research.


Subject(s)
Air Pollutants , Composting , Volatile Organic Compounds , Air Pollutants/analysis , Humans , Risk Assessment , Volatile Organic Compounds/analysis , Composting/methods , Odorants/analysis , Ammonia/analysis , Air Pollution/prevention & control , Air Pollution/statistics & numerical data , Methane/analysis , Hydrogen Sulfide/analysis , Environmental Monitoring/methods
16.
iScience ; 27(4): 109398, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38544573

ABSTRACT

Mitochondria play a vital role in non-shivering thermogenesis in both brown and subcutaneous white adipose tissues (BAT and scWAT, respectively). However, specific regulatory mechanisms driving mitochondrial function in these tissues have been unclear. Here we demonstrate that prolonged activation of ß-adrenergic signaling induces epigenetic modifications in scWAT, specifically targeting the enhancers for the mitochondria master regulator genes Pgc1a/b. This is mediated at least partially through JMJD1A, a histone demethylase that in response to ß-adrenergic signals, facilitates H3K9 demethylation of the Pgc1a/b enhancers, promoting mitochondrial biogenesis and the formation of beige adipocytes. Disruption of demethylation activity of JMJD1A in mice impairs activation of Pgc1a/b driven mitochondrial biogenesis and limits scWAT beiging, contributing to reduced energy expenditure, obesity, insulin resistance, and metabolic disorders. Notably, JMJD1A demethylase activity is not required for Pgc1a/b dependent thermogenic capacity of BAT especially during acute cold stress, emphasizing the importance of scWAT thermogenesis in overall energy metabolism.

17.
Opt Express ; 21(7): 8630-7, 2013 Apr 08.
Article in English | MEDLINE | ID: mdl-23571953

ABSTRACT

An Analytical Band Monte Carlo model was used to investigate the temperature dependence of impact ionization in InAs. The model produced an excellent agreement with experimental data for both avalanche gain and excess noise factors at all temperatures modeled. The gain exhibits a positive temperature dependence whilst the excess noise shows a very weak negative dependence. These dependencies were investigated by tracking the location of electrons initiating the ionization events, the distribution of ionization energy and the effect of threshold energy. We concluded that at low electric fields, the positive temperature dependence of avalanche gain can be explained by the negative temperature dependence of the ionization threshold energy. At low temperature most electrons initiating ionization events occupy L valleys due to the increased ionization threshold. As the scattering rates in L valleys are higher than those in Γ valley, a broader distribution of ionization energy was produced leading to a higher fluctuation in the ionization chain and hence the marginally higher excess noise at low temperature.


Subject(s)
Arsenicals/chemistry , Indium/chemistry , Models, Chemical , Computer Simulation , Electromagnetic Fields , Ions , Semiconductors , Temperature
18.
Article in English | MEDLINE | ID: mdl-37314913

ABSTRACT

Owing to its simplicity, the traditional k -means (Lloyd heuristic) clustering method plays a vital role in a variety of machine-learning applications. Disappointingly, the Lloyd heuristic is prone to local minima. In this article, we propose k -mRSR, which converts the sum-of-squared error (SSE) (Lloyd) into a combinatorial optimization problem and incorporates a relaxed trace maximization term and an improved spectral rotation term. The main advantage of k -mRSR is that it only needs to solve the membership matrix instead of computing the cluster centers in each iteration. Furthermore, we present a nonredundant coordinate descent method that brings the discrete solution infinitely close to the scaled partition matrix. Two novel findings from the experiments are that k -mRSR can further decrease (increase) the objective function values of the k -means obtained by Lloyd (CD), while Lloyd (CD) cannot decrease (increase) the objective function obtained by k -mRSR. In addition, the results of extensive experiments on 15 datasets indicate that k -mRSR outperforms both Lloyd and CD in terms of the objective function value and outperforms other state-of-the-art methods in terms of clustering performance.

19.
Int J Biol Macromol ; 253(Pt 1): 126536, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37634775

ABSTRACT

The adverse effects of heavy metal pollutants in wastewater have threatened human health in recent decades. Therefore, the development of absorbents for such pollutants is essential to overcome these problems. Electrospun nanofibers are often used for wastewater treatment owing to their high porosity and high specific surface area. Zein from plants and collagen from animals are vulnerable to moisture, which limits its broad application in practice. However fully biodegradable polyvinyl alcohol (PVA), which is soluble in water, can be mixed with protein individually to overcome the limitation. In this work, the two proteins described above and PVA were combined to prepare protein nanofibers by electrospinning technology, which could achieve adsorption of Cu2+. As the protein content increased, the adsorption properties of the obtained nanofibers for Cu2+ showed a rising and then decreasing trend, with the highest point at 50 % of protein content, especially the collagen nanofibers, which reached 24.62 mg/g. Both protein nanofibers reached adsorption equilibrium after 15 h, but overall, collagen nanofibers showed a superior adsorption performance for Cu2+ than that by zein nanofibers. In the process of Cu2+ adsorption by protein nanofibers, both physical and chemical effect existed, and the physical effect played the leading role.


Subject(s)
Environmental Pollutants , Metals, Heavy , Nanofibers , Water Pollutants, Chemical , Zein , Humans , Polyvinyl Alcohol/chemistry , Nanofibers/chemistry , Adsorption , Ions , Collagen , Water Pollutants, Chemical/chemistry
20.
Sci Total Environ ; 891: 164608, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37286002

ABSTRACT

The conversion of organic matter and P in the waste composting process affects the efficiency of the composted product. However, the addition of microbial inoculants may improve the conversion characteristics of organic matter and P. In this study, straw-decomposing microbial inoculant (SDMI) was added to investigate its effects on the organic matter stabilization and phosphorus activation during the composting of vegetable waste (VWs). Aliphatic carboxyl-containing compounds were degraded during composting, but the stability of the organic matter and P was improved. The addition of SDMI promoted the degradation of dissolved organic carbon by 81.7 % and improved P stability and thermal stability of organic matter. Hedley sequential P fractionation showed a decrease in the H2O-P proportion by >12 % and increased in the HCl-P proportion by >4 % by the end of composting. Stable forms of P, such as AlPO4 and iron-containing phosphate, were the main forms of P in the final compost. The results provide a basis for producing high-quality vegetable compost products and improving the reutilization potential of VWs.


Subject(s)
Agricultural Inoculants , Composting , Composting/methods , Phosphorus/metabolism , Vegetables/metabolism , Agricultural Inoculants/metabolism , Soil
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