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1.
J Hazard Mater ; 471: 134324, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38640666

RESUMEN

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.

2.
Small ; : e2402726, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651509

RESUMEN

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.
Clin Microbiol Rev ; : e0016123, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634634

RESUMEN

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.

4.
iScience ; 27(4): 109398, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38544573

RESUMEN

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.

5.
Environ Pollut ; 346: 123682, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38428788

RESUMEN

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.


Asunto(s)
Microplásticos , Polipropilenos , Plásticos , Dióxido de Carbono , Humedales , Sedimentos Geológicos
6.
Opt Express ; 31(20): 33141-33149, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859101

RESUMEN

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.

7.
Int J Biol Macromol ; 253(Pt 1): 126536, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37634775

RESUMEN

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.


Asunto(s)
Contaminantes Ambientales , Metales Pesados , Nanofibras , Contaminantes Químicos del Agua , Zeína , Humanos , Alcohol Polivinílico/química , Nanofibras/química , Adsorción , Iones , Colágeno , Contaminantes Químicos del Agua/química
8.
Int Wound J ; 20(10): 4300-4307, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37493021

RESUMEN

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.


Asunto(s)
Laparoscopía , Neoplasias Gástricas , Humanos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/cirugía , Neoplasias Gástricas/cirugía , Gastrectomía/efectos adversos , Gastrectomía/métodos , Laparoscopía/efectos adversos , Laparoscopía/métodos , China/epidemiología
9.
Artículo en Inglés | MEDLINE | ID: mdl-37314913

RESUMEN

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.

10.
Sci Total Environ ; 891: 164608, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37286002

RESUMEN

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.


Asunto(s)
Inoculantes Agrícolas , Compostaje , Compostaje/métodos , Fósforo/metabolismo , Verduras/metabolismo , Inoculantes Agrícolas/metabolismo , Suelo
11.
Front Psychol ; 13: 1005249, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467173

RESUMEN

The impact of CEOs' psychological traits on firms' decision-making has been explored by many psychological researchers. What's more, the CEO hometown identity, as one of the most fundamental psychological traits, has drawn increasing attention from the psychological literature. Firms' adoption of blockchain technology plays an innovative and efficient role in firms' strategic transformation. Thus, it is necessary to investigate the relationship between CEOs' psychological traits and firms' adoptions of blockchain technology from the perspective of hometown identity. To examine the impact of the CEO hometown identity on firms' adoption of blockchain technology, this paper manually collects information about the CEO hometown identity and constructs the index of firms' adoption of blockchain technology based on the textual analysis of firms' annual reports. Based on the theory about the psychology of identity, this paper constructs the theoretical hypothesis about the relationship between CEO hometown identity and firms' adoption of blockchain technology. Then, this paper uses a two-way fixed effect regression model to estimate the impact of the CEO hometown identity on firms' adoption of blockchain technology based on the panel data of Chinese A-share non-financial listed firms during 2008-2019. The research results show that: (1) the CEO hometown identity has a positive effect on firms' adoption of blockchain technology. (2) For firms with severe financing constraints and State-owned enterprises (SOEs), the positive effect of the CEO hometown identity on firms' adoption of blockchain technology is more prominent. (3) Our benchmark results still hold after a series of robustness checks, including altering the measurement of the CEO hometown identity, altering the sample, adding CEO-specific control variables, and altering the logit regression model. Based on the above-mentioned findings, this paper not only sheds new light on the power of CEOs' psychological trait but also deepens the understanding about theories of the psychology of identity.

12.
Nat Commun ; 13(1): 5715, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36175407

RESUMEN

Protein kinase A promotes beige adipogenesis downstream from ß-adrenergic receptor signaling by phosphorylating proteins, including histone H3 lysine 9 (H3K9) demethylase JMJD1A. To ensure homeostasis, this process needs to be reversible however, this step is not well understood. We show that myosin phosphatase target subunit 1- protein phosphatase 1ß (MYPT1-PP1ß) phosphatase activity is inhibited via PKA-dependent phosphorylation, which increases phosphorylated JMJD1A and beige adipogenesis. Mechanistically, MYPT1-PP1ß depletion results in JMJD1A-mediated H3K9 demethylation and activation of the Ucp1 enhancer/promoter regions. Interestingly, MYPT1-PP1ß also dephosphorylates myosin light chain which regulates actomyosin tension-mediated activation of YAP/TAZ which directly stimulates Ucp1 gene expression. Pre-adipocyte specific Mypt1 deficiency increases cold tolerance with higher Ucp1 levels in subcutaneous white adipose tissues compared to control mice, confirming this regulatory mechanism in vivo. Thus, we have uncovered regulatory cross-talk involved in beige adipogenesis that coordinates epigenetic regulation with direct activation of the mechano-sensitive YAP/TAZ transcriptional co-activators.


Asunto(s)
Adipogénesis , Cromatina , Fosfatasa de Miosina de Cadena Ligera/metabolismo , Actomiosina , Adipogénesis/genética , Animales , Proteínas Quinasas Dependientes de AMP Cíclico , Epigénesis Genética , Histonas , Lisina , Ratones , Cadenas Ligeras de Miosina , Fosfatasa de Miosina de Cadena Ligera/genética , Monoéster Fosfórico Hidrolasas
13.
RSC Adv ; 12(32): 20857-20865, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35919138

RESUMEN

In view of the diversification of pollutants in current sewage, further improving the application efficiency of water treatment agents and realizing multi-functionalization are important directions for the research of water treatment agents. In this paper, on the basis of the natural polymer flocculant chitosan, MAPTAC and AM were used as modified monomers to improve its solubility and also enhance its flocculation and bactericidal properties. Furthermore, the preparation conditions of chitosan flocculant poly(CTS-g-AM-MAPTAC) were optimized by response surface methodology, and its flocculation and sterilization functions were evaluated in detail. The experimental results showed that the significance order of the factors in the preparation process was illumination time, mass ratio of total monomer to chitosan, molar ratio of monomers, and initiator concentration. The optimum conditions for preparing poly(CTS-g-AM-MAPTAC) were 6 moL L-1 for initiator concentration, 4 for mass ratio of total monomer to chitosan, 25% for monomer molar ratio, and 60 min for illumination time. The intrinsic viscosity and grafting rate of poly(CTS-g-AM-MAPTAC) prepared under optimum conditions were 5.4965 dL g-1 and 220.34%. The obtained poly(CTS-g-AM-MAPTAC) had good solubility, which could fully expose the active sites in wastewater with different acidity and had good flocculation effect. The performance evaluation results showed that the flocculant had a good combination of flocculation and sterilization, and had the advantages of high turbidity removal and sterilization efficiency, good biodegradability and low reagent consumption.

14.
J Environ Sci (China) ; 107: 150-159, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34412778

RESUMEN

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.


Asunto(s)
Dípteros , Metales Pesados , Animales , Cobre/toxicidad , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Incidencia , Larva , Metales Pesados/toxicidad
15.
J Phys Chem Lett ; 12(30): 7229-7235, 2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34310154

RESUMEN

Carbon disulfide is an archetypal double-bonded molecule belonging to the class of group IV-group VI, AB2 compounds. It is widely believed that, upon compression to several GPa at room temperature and above, a polymeric chain of type (-(C═S)-S-)n, named Bridgman's black polymer, will form. By combining optical spectroscopy and synchrotron X-ray diffraction data with ab initio simulations, we demonstrate that the structure of this polymer is different. Solid molecular CS2 polymerizes at ∼10-11 GPa. The polymer is disordered and consists of a mixture of 3-fold (C3) and 4-fold (C4) coordinated carbon atoms with some C═C double bonds. The C4/C3 ratio continuously increases upon further compression to 40 GPa. Upon decompression, structural changes are partially reverted, while the sample also undergoes partial disproportionation. Our work uncovers the nontrivial high-pressure structural evolution in one of the simplest molecular systems exhibiting molecular as well as polymeric phases.

16.
Ecotoxicol Environ Saf ; 211: 111925, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33465627

RESUMEN

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.


Asunto(s)
Biotransformación/fisiología , Dípteros/fisiología , Metales/metabolismo , Animales , Heces , Microbioma Gastrointestinal , Larva , Ganado , Estiércol , Nitrógeno , Porcinos
17.
Artículo en Inglés | MEDLINE | ID: mdl-32824886

RESUMEN

OBJECTIVES: This study aimed to examine the prevalence of medication non-adherence among older adults with diabetes mellitus (DM) in Shandong province, China and to identify its influencing factors. METHODS: A sample of 1002 older adults aged 60 or above with DM was analyzed. Medication adherence was measured using the Morisky-Green-Levine (MGL) Medication Adherence Scale. Descriptive statistical analysis, chi-square test, univariate and multivariate logistic regression analyses were employed. RESULTS: The prevalence of self-reported medication non-adherence among older adults with DM was 19.9%. Female respondents (adjusted odds ratio (AOR) = 1.56, 95% CI: 1.09-2.24) and respondents who perceived medication adherence to be unimportant (AOR = 1.69, 95% CI: 1.05-2.74) were more likely to experience medication non-adherence. Respondents with 5 years of disease duration or longer were less likely (AOR = 0.63, 95% CI: 0.46-0.87) to experience medication non-adherence. CONCLUSIONS: This study showed that about one out of five older adults with DM in Shandong province, China, experienced medication non-adherence, and that gender, disease duration and perceived importance of medication adherence were associated with medication non-adherence in this population group. Provision of counseling and health education programs could be the future priority to raise patients' awareness of the importance of medication adherence and improve patients' self-management of DM.


Asunto(s)
Diabetes Mellitus , Cumplimiento de la Medicación , Anciano , Pueblo Asiatico , China , Estudios Transversales , Diabetes Mellitus/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Sci Total Environ ; 744: 140920, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-32711322

RESUMEN

The impact of pile temperature on the fate of antibiotic resistance genes (ARGs), metal resistance genes (MRGs) and mobile genetic elements (MGEs) during aerobic composting was not fully explored. Here, three composting piles were tested with different maximum temperature control. A total of 211 ARGs, 9 MRGs and 44 MGEs were observed. After 42 days, the numbers and the total abundances of detected genes were generally decreased (3.8%-50.0% and 25.4%-66.0%, respectively) in three treatments, except for the total abundance of MRGs (increased by 82.2%-500.5%). Higher pile temperature substantially stimulated the attenuation of gene diversity, but had no significant impact on promoting the decline in total abundances. For certain gene subtypes, higher temperature remarkably promoted their removal or suppressed their rebounding during maturation phase. The erm(F), sul1 and floR were potential indicators of ARGs during composting. The MGEs IS26, int1, intl2, IncP_oriT and IncQ_oriT acted as crucial hubs for ARGs and MRGs. Genera Acinetobacter, Pseudomonas, Corynebacterium_1 and Proteiniphilum were major potential hosts for multiple genes. The ARG, MRG and MGE profiles were mainly driven by the joint effect of environmental factors and microbial community.


Asunto(s)
Compostaje , Microbiota , Animales , Antibacterianos/farmacología , Farmacorresistencia Microbiana/efectos de los fármacos , Genes Bacterianos , Estiércol , Metales , Porcinos , Temperatura
19.
Ecotoxicol Environ Saf ; 192: 110323, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32066008

RESUMEN

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.


Asunto(s)
Dípteros/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Metales Pesados/farmacología , Animales , Bacterias/aislamiento & purificación , Bioacumulación , Cadmio/farmacocinética , Cadmio/farmacología , Cobre/farmacocinética , Cobre/farmacología , Dípteros/crecimiento & desarrollo , Dípteros/metabolismo , Dípteros/microbiología , Heces/química , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/metabolismo , Larva/microbiología , Metales Pesados/farmacocinética , Eliminación de Residuos
20.
Sci Rep ; 8(1): 9107, 2018 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-29904062

RESUMEN

The electron and hole avalanche multiplication characteristics have been measured in bulk AlAs0.56Sb0.44 p-i-n and n-i-p homojunction diodes, lattice matched to InP, with nominal avalanche region thicknesses of ~0.6 µm, 1.0 µm and 1.5 µm. From these and data from two much thinner devices, the bulk electron and hole impact ionization coefficients (α and ß respectively), have been determined over an electric-field range from 220-1250 kV/cm for α and from 360-1250 kV/cm for ß for the first time. The α/ß ratio is found to vary from 1000 to 2 over this field range, making it the first report of a wide band-gap III-V semiconductor with ionization coefficient ratios similar to or larger than that observed in silicon.

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