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1.
Proc Natl Acad Sci U S A ; 119(28): e2123274119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35759652

RESUMO

Biotic interactions that hierarchically organize ecosystems by driving ecological and evolutionary processes across spatial scales are ubiquitous in our biosphere. Biotic interactions have been extensively studied at local and global scales, but how long-distance, cross-ecosystem interactions at intermediate landscape scales influence the structure, function, and resilience of ecological systems remains poorly understood. We used remote sensing, modeling, and field data to test the hypothesis that the long-distance impact of an invasive species dramatically affects one of the largest tidal flat ecosystems in East Asia. We found that the invasion of exotic cordgrass Spartina alterniflora can produce long-distance effects on native species up to 10 km away, driving decadal coastal ecosystem transitions. The invasive cordgrass at low elevations facilitated the expansion of the native reed Phragmites australis at high elevations, leading to the massive loss and reduced resilience of the iconic Suaeda salsa "Red Beach" marshes at intermediate elevations, largely as a consequence of reduced soil salinity across the landscape. Our results illustrate the complex role that long-distance interactions can play in shaping landscape structure and ecosystem resilience and in bridging the gap between local and global biotic interactions.


Assuntos
Biota , Espécies Introduzidas , Poaceae , Áreas Alagadas , Salinidade , Solo/química
2.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35012978

RESUMO

Preventing pathogenic viral and bacterial transmission in the human environment is critical, especially in potential outbreaks that may be caused by the release of ancient bacteria currently trapped in the permafrost. Existing commercial disinfectants present issues such as a high carbon footprint. This study proposes a sustainable alternative, a bioliquid derived from biomass prepared by hydrothermal liquefaction. Results indicate a high inactivation rate of pathogenic virus and bacteria by the as-prepared bioliquid, such as up to 99.99% for H1N1, H5N1, H7N9 influenza A virus, and Bacillus subtilis var. niger spores and 99.49% for Bacillus anthracis Inactivation of Escherichia coli and Staphylococcus epidermidis confirmed that low-molecular-weight and low-polarity compounds in bioliquid are potential antibacterial components. High temperatures promoted the production of antibacterial substances via depolymerization and dehydration reactions. Moreover, bioliquid was innoxious as confirmed by the rabbit skin test, and the cost per kilogram of the bioliquid was $0.04427, which is notably lower than that of commercial disinfectants. This study demonstrates the potential of biomass to support our biosafety with greater environmental sustainability.


Assuntos
Biomassa , Contenção de Riscos Biológicos , Meio Ambiente , Energia Renovável , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Humanos , Testes de Sensibilidade Microbiana , Peso Molecular , Pandemias , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/ultraestrutura
3.
J Appl Microbiol ; 135(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38192042

RESUMO

AIM: This study aimed to investigate the positive effect of natto powder on obese rats fed with a high-fat diet (HFD). METHODS AND RESULTS: Sprague-Dawley rats were fed with a HFD for 8 weeks continuously and gavaged with natto powder, respectively, for 8 weeks starting from the ninth week. The results showed that natto powder significantly reduced the body weight of rats and maintained the balance of cholesterol metabolism in the body by inhibiting the activity of liver X receptors (LXR) target genes, increasing the active expression of cholesterol 7 alpha-hydroxylase, and reducing the active expression of sterol-regulatory element-binding protein and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR). Furthermore, natto powder increased the relative abundance of potentially beneficial microbiota in gut and decreased the relative abundance of obesity-related harmful bacteria, and also increased the Bacteroidetes/Firmicutes ratio and improved the composition of gut microbiota. CONCLUSIONS: Natto powder maintains the balance of cholesterol metabolism by inhibiting the LXR pathway and regulating the gut microbiota.


Assuntos
Microbioma Gastrointestinal , Alimentos de Soja , Ratos , Animais , Camundongos , Pós/farmacologia , Receptores X do Fígado , Ratos Sprague-Dawley , Obesidade/microbiologia , Dieta Hiperlipídica , Colesterol/metabolismo , Camundongos Endogâmicos C57BL
4.
Sensors (Basel) ; 23(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37765904

RESUMO

The precursors that appear when geological disasters occur are geotechnical deformations. This paper studies the TDR (Time Domain Reflection) measurement technology for the distributed measurement of geotechnical deformation using parallel spiral wire as a sensor, which is used for monitoring and early warning detection of geological disasters. Based on the mechanism of the electromagnetic field distribution parameters of the parallel spiral sensing wire, the relationship between the stretching amount of the parallel spiral wire and the change in its characteristic impedance is analyzed. When the parallel spiral wire is buried in the soil, the geotechnical deformation causes the parallel spiral wire to be stretched, and according to its characteristic impedance change, the stretching position and the stretching degree can be obtained, thus realizing the distributed measurement of geotechnical deformation. Based on this principle, the TDR measurement system is developed, and a local single-point stretching amount and stretching positioning experiment are designed for the parallel spiral sensing line to verify the effectiveness of the sensing technology and the usability of the measurement system.

5.
Molecules ; 28(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38138505

RESUMO

Soybean meal (SBM) is a high-quality vegetable protein, whose application is greatly limited due to its high molecular weight and anti-nutritional properties. The aim of this study was to modify the protein of soybean meal via solid-state fermentation of Bacillus subtilis. The fermentation conditions were optimized as, finally, the best process parameters were obtained, namely fermentation temperature of 37 °C, inoculum amount of 12%, time of 47 h, and material-liquid ratio of 1:0.58, which improved the content of acid-soluble protein. To explore the utilization of modified SBM as a food ingredient, the protein structure and properties were investigated. Compared to SBM, the protein secondary structure of fermented soybean meal (FSBM) from the optimal process decreased by 8.3% for α-helix content, increased by 3.08% for ß-sheet, increased by 2.71% for ß-turn, and increased by 2.51% for random coil. SDS-PAGE patterns showed that its 25-250 KDa bands appeared to be significantly attenuated, with multiple newborn peptide bands smaller than 25 KDa. The analysis of particle size and zeta potential showed that fermentation reduced the average particle size and increased the absolute value of zeta potential. It was visualized by SEM and CLSM maps that the macromolecular proteins in FSBM were broken down into fragmented pieces with a folded and porous surface structure. Fermentation increased the solubility, decreased the hydrophobicity, increased the free sulfhydryl content, decreased the antigenicity, improved the protein properties of SBM, and promoted further processing and production of FSBM as a food ingredient.


Assuntos
Ingredientes de Alimentos , Proteínas de Soja , Humanos , Recém-Nascido , Proteínas de Soja/metabolismo , Bacillus subtilis/metabolismo , Fermentação , Farinha , Glycine max , Ração Animal/análise
6.
Molecules ; 28(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36770993

RESUMO

Soybean residue is a by-product of soybean product production that is wasted unreasonably at present. Accomplishing the efficient utilization of soybean residue can save resources. A composite microbial system was constructed using lactic acid bacteria (LAB) and Saccharomyces cerevisiae (SC), and modified soybean residue was prepared by solid fermentation. In order to explore the value of modified soybean residue as a food raw material, its physical and chemical properties, adsorption properties, and antioxidant properties were studied. The results showed that the soluble dietary fiber (SDF) yield of mixed fermentation (MF) increased significantly. Both groups of soybean residues had representative polysaccharide infrared absorption peaks, and MF showed a looser structure and lower crystallinity. In terms of the adsorption capacity index, MF also has a higher adsorption capacity for water molecules, oil molecules, and cholesterol molecules. In addition, the in vitro antioxidant capacity of MF was also significantly higher than that of unfermented soybean residue (UF). In conclusion, our study shows that mixed fermentation could increase SDF content and improve the functional properties of soybean residue. Modified soybean residue prepared by mixed fermentation is the ideal food raw material.


Assuntos
Antioxidantes , Glycine max , Glycine max/química , Antioxidantes/química , Fermentação , Fibras na Dieta , Adsorção
7.
Biochem Biophys Res Commun ; 603: 160-166, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35298948

RESUMO

Obesity has become the second leading cause of death globally after smoking. Probiotic Bacillus has noticeable weight-loss effects. This study aimed to investigate the mechanism of Bacillus natto (B. natto) on insulin resistance in obese rats. The obese rat model was established with a HFD for 8 weeks, and then, B. natto was orally administered at different dosed for 8 weeks. The results showed that B. natto significantly reduced the body weight, epididymis fat weight, total cholesterol, triglyceride, low-density lipoprotein while increasing the level of high-density lipoprotein in HFD rats. B. natto intervention improved liver injury by reducing alanine aminotransferase and aspartate transaminase levels. B. natto intervention was also beneficial for the inhibition of hepatic steatosis and inflammation factors in HFD rats by inhibiting the mRNA expression level of SREBP-1 gene. Moreover, B. natto improved insulin resistance homeostasis by activating PI3K/AKT signaling pathway. Therefore, B. natto could be used as a potential probiotic supplement to provided new strategy for the prevention and treatment of metabolic diseases such as obesity.


Assuntos
Bacillus , Resistência à Insulina , Alimentos de Soja , Animais , Bacillus/metabolismo , Dieta Hiperlipídica , Insulina/metabolismo , Fígado/metabolismo , Masculino , Obesidade/metabolismo , Obesidade/terapia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
8.
Genet Med ; 24(12): 2501-2515, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36178483

RESUMO

PURPOSE: The study aimed to identify novel genes for idiopathic hypogonadotropic hypogonadism (IHH). METHODS: A cohort of 1387 probands with IHH underwent exome sequencing and de novo, familial, and cohort-wide investigations. Functional studies were performed on 2 p190 Rho GTPase-activating proteins (p190 RhoGAP), ARHGAP35 and ARHGAP5, which involved in vivo modeling in larval zebrafish and an in vitro p190A-GAP activity assay. RESULTS: Rare protein-truncating variants (PTVs; n = 5) and missense variants in the RhoGAP domain (n = 7) in ARHGAP35 were identified in IHH cases (rare variant enrichment: PTV [unadjusted P = 3.1E-06] and missense [adjusted P = 4.9E-03] vs controls). Zebrafish modeling using gnrh3:egfp phenotype assessment showed that mutant larvae with deficient arhgap35a, the predominant ARHGAP35 paralog in the zebrafish brain, display decreased GnRH3-GFP+ neuronal area, a readout for IHH. In vitro GAP activity studies showed that 1 rare missense variant [ARHGAP35 p.(Arg1284Trp)] had decreased GAP activity. Rare PTVs (n = 2) also were discovered in ARHGAP5, a paralog of ARHGAP35; however, arhgap5 zebrafish mutants did not display significant GnRH3-GFP+ abnormalities. CONCLUSION: This study identified ARHGAP35 as a new autosomal dominant genetic driver for IHH and ARHGAP5 as a candidate gene for IHH. These observations suggest a novel role for the p190 RhoGAP proteins in GnRH neuronal development and integrity.


Assuntos
Hipogonadismo , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/genética , Hipogonadismo/genética , Hormônio Liberador de Gonadotropina/genética , Proteínas Repressoras , Fatores de Troca do Nucleotídeo Guanina , Proteínas Ativadoras de GTPase/genética
9.
Opt Express ; 30(2): 1686-1698, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209324

RESUMO

This work proposes a robust unwrapping algorithm for noisy and steep phase maps based on the residue calibrated least-squares method. The proposed algorithm calculates and calibrates the residues in the derivative maps to get a noise-free Poisson equation. Moreover, it compensates for the residuals between the wrapped and unwrapped phase maps iteratively to eliminate approximation errors and the smoothing effect of the least-squares method. The robustness and efficiency of the proposed algorithm are validated by unwrapping simulated and experimentally wrapped phase maps. Compared with the other three typical algorithms, the proposed algorithm has the most effective performance in noisy and steep phase unwrapping, providing a reliable alternative for practical applications.

10.
Opt Express ; 30(20): 35759-35775, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258520

RESUMO

The polarization based phase shifting method is an effective way for dynamic measurements. However, when this technique is applied to the measurements of large optics, the interferometric results are easily limited by the birefringence of large optics. The birefringence changes the polarization states of reference light and test light, and brings constant polarization aberrations into the measurement results independent of the phase shifting procedure. In this article, the detailed theoretical analysis on the mechanism of polarization aberration is presented. Afterwards, we propose a new interferometric method to determine the birefringence effects by measuring the transmitted wavefronts of the large optics, which are considered as birefringent samples. Theoretical analysis shows that the polarization error in the linearly polarized system can be corrected by two independent measurements with orthogonal polarization states. The phase retardance can be obtained from the wavefront difference of the transmitted wavefronts when switching the polarization states of the incident lights. The birefringence distribution obtained is used to calibrate the polarization aberrations in the measurement result of a homemade large aperture measurement platform and the correction result is compared with the result via the wavelength tuning phase shifting method. The elimination of the polarization aberrations can be observed in the final results.

11.
Cardiovasc Diabetol ; 21(1): 201, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192784

RESUMO

BACKGROUND: Recent literature reported the biological role of C-peptide, but this role is still controversial and unclear. The primary aim of this study was to investigate associations between C-peptide and cardiovascular biomarkers as well as events. METHODS: A total of 55636 participants who had a health examination from 2017 to 2021 were included. Of them, 6727 participants visited the hospital at least twice. Cardiovascular biomarkers like high-sensitivity C-reactive protein (hs-CRP) and high-sensitivity cardiac troponin T (hs-cTnT) were measured and their relationships with fasting C-peptide were evaluated for all participants. Cardiovascular events were obtained during the last visit and their associations with C-peptide were evaluated for those participants who visited the hospital at least twice. RESULTS: Among the included participants, 11.1% had a previous type 2 diabetes mellitus (T2DM). In the participants without previous T2DM, the relationships between fasting C-peptide and hs-CRP and hs-cTnT were negative if the value of fasting C-peptide was < 1.4 ng/mL and positive if the value was ≥ 1.4 ng/mL. These relationships remained significant after adjusting for hemoglobin A1c, insulin resistance index, and its interaction with C-peptide, even if the participants were stratified by glucose metabolism status or levels of insulin resistance index. Hazard ratios of cardiovascular events were first decreased and then increased with the increasing of baseline C-peptide levels, though these associations became unsignificant using the multivariate Cox regression model. Unlike the participants without previous T2DM, the associations of C-peptide with cardiovascular biomarkers and events were not significant in the patients with previous T2DM. CONCLUSIONS: The associations of C-peptide with cardiovascular biomarkers and events were different between the participants without previous T2DM and those with previous T2DM. The effect of C-peptide on cardiovascular risk may be bidirectional, play a benefit role at a low level, and play a harmful role at a high level in the nondiabetic adults and the patients with newly diagnosed T2DM.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Adulto , Biomarcadores , Peptídeo C , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Glucose , Hemoglobinas Glicadas/metabolismo , Fatores de Risco de Doenças Cardíacas , Humanos , Estudos Retrospectivos , Fatores de Risco , Troponina T
12.
Opt Lett ; 47(17): 4371-4374, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048656

RESUMO

Segmented phase unwrapping is an intractable problem in the phase-shifting technique. To solve the problem, this Letter presents an iterative pseudo-phase inpainting algorithm (IPPI). By means of image inpainting, the IPPI can be used to realize the pseudo-phases connecting each other among these phase islands. The error points in the pseudo-phases can be reduced by iterations of phase inpainting with the assistance of the reference pseudo-phase obtained by introducing the numerical carrier frequency and using the 2D Fourier transform. Compared with other methods, the proposed algorithm does not have to do any processing on the effective area of the wrapped phase, which ensures the authenticity of the result. The simulated and experimental verifications show that the proposed method not only possesses high precision, but also can be applied to a segmented phase with severe noise.

13.
J Appl Microbiol ; 133(6): 3634-3644, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36036228

RESUMO

AIMS: This study aimed to investigate the effects of Bacillus subtilis natto JLCC513 (JLCC513) on gut microbiota, inflammation and intestinal barrier function in high-fat-diet (HFD) rats. METHODS AND RESULTS: Sprague-Dawley (SD) rats were fed HFD for 16 weeks, and treated with JLCC513 in 9th week. The oral administration of JLCC513 decreased body weight and reduced the inflammation level in HFD rats. Pathologically, JLCC513 prevented the detachment of ileal villus and increased the villus height in rats. Mechanistically, western blot analysis showed that the protein levels of tight junction (TJ) proteins involved in intestinal barrier function, including zonula occludens-1 (ZO-1), occludin and claudin-1, were increased after JLCC513 treatment. Meanwhile, JLCC513 treatment also decreased the protein levels of toll-like receptor 4 (TLR4), nuclear factor kappa-B (NF-κB) and NOD-like receptor protein 3 (NLRP3), indicating inhibition of the TLR4/NF-κB/NLRP3 pathway. Furthermore, faecal analysis showed that JLCC513 increased the abundance of Lactobacillus and Oscillospira and the ratio of Firmicutes/Bacteroidetes (F/B), and decreased the levels of Blautia and C_Clostridium. CONCLUSIONS: JLCC513 alleviated intestinal barrier dysfunction by inhibiting TLR4/NF-κB/NLRP3 pathway and regulating gut microbiota disorders. SIGNIFICANCE AND IMPACT OF STUDY: Our study might provide new treatment strategies for obesity and metabolic diseases.


Assuntos
Microbioma Gastrointestinal , Alimentos de Soja , Ratos , Animais , Receptor 4 Toll-Like , NF-kappa B/metabolismo , Bacillus subtilis/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Obesidade , Mucosa Intestinal/metabolismo , Inflamação
14.
BMC Geriatr ; 22(1): 245, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331164

RESUMO

BACKGROUND: The association of vitamin D with all-cause mortality remains controversial and longitudinal evidence exploring the potential effects of change in vitamin D status is limited in the oldest old (aged ≥ 80 years old). We aimed to study the relationship between vitamin D change and all-cause mortality among older Chinese adults including the oldest old. METHODS: The data of Chinese Longitudinal and Health Longevity Study in 2012 and 2014 wave was used for baseline data. Mortality was assessed in the subsequent 2018 survey waves. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% confidence interval (CI) of all-cause mortality related to vitamin D change, including maintaining deficiency or no deficiency, deficiency to no deficiency, and no deficiency to deficiency, using below 50 nmol/L as definition of deficiency. RESULTS: The mean age of the total 1362 participants was 84.4 ± 12.1(60-113) years. The prevalence of vitamin D deficiency was 67.5% and 68.4% in 2012 and 2014 wave respectively, and significantly differed by sex and age at baseline. Cox regression showed that participants with deficiency to no deficiency and maintaining no deficiency of vitamin D status had decreased HR for all-cause mortality, compared to the maintaining deficiency group. The HRs for mortality were 0.70(95%CI: 0.50-0.96, p = 0.028) and 0.47(95%CI: 0.33-0.68, p < 0.001) respectively in the adjusted model. Also, females and the oldest old had a greatest reduction in mortality risk. And no significant difference in mortality in the no deficiency to deficiency group. CONCLUSIONS: Not only maintaining no deficiency, but also the change from deficiency to no deficiency of vitamin D status were associated with lower risk of all-cause mortality, especially in the female and oldest-old participants initially with low vitamin D level.


Assuntos
Deficiência de Vitamina D , Vitamina D , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Deficiência de Vitamina D/diagnóstico , Vitaminas
15.
Bull Environ Contam Toxicol ; 108(6): 1132-1138, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35577927

RESUMO

In this study, pumpkin seedlings were subjected to cadmium stress (100 mg/L cadmium ion solution, 10 days) without or with wheat straw biochar at different concentrations (0%, 0.5%, 1%, and 2% w/v). As the biochar concentration increased, the amount of cadmium accumulated in the root and stem of pumpkin seedlings decreased and the fresh weight of root, stem and leaf increased. The highest cadmium concentration was in the root, followed by the stem and then the leaf. 1% and 2% biochar treatments reduced the oxidative stress of cadmium to seedlings, and added the contents of fatty acid, carbohydrate, amino acid and indoleacetic acid in the root. With the increase of biochar concentration, the metabolites promoting root growth increased. These results provide new information about how biochar alleviates cadmium stress by affecting the metabolic response.


Assuntos
Cucurbita , Poluentes do Solo , Cádmio/análise , Carvão Vegetal/química , Cucurbita/metabolismo , Plântula , Solo/química , Poluentes do Solo/análise
16.
Bull Environ Contam Toxicol ; 108(1): 129-135, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34652458

RESUMO

In this study, pot-culture experiments were conducted to investigate the single effect of Cd, PCBs, and the combined effect of Cd-PCBs with Tagetes patula L. The study highlights that the minimum concentration of PCBs (100 µg kg-1) could enable the growth of the plant with an increase in biomass by 27.76% when compared with the control. In all the experiments performed, the Cd concentrations over the surface parts were found to be above 100 mg kg-1. Significant positive correlations were observed between the Cd and PCBs concentrations accumulated in tissues of the soil and plants (p < 0.05). T. patula exhibited high tolerance to Cd and PCBs, and the plant promoted the removal rate of PCBs. The removal rates of PCB18 and PCB28 were up to 42.72 and 42.29%, respectively. The study highlights the potential and suitability of T. patula for phytoremediation of Cd and PCBs in contaminated soils.


Assuntos
Bifenilos Policlorados , Poluentes do Solo , Tagetes , Biodegradação Ambiental , Cádmio/análise , Solo , Poluentes do Solo/análise
17.
J Proteome Res ; 20(5): 2839-2850, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33872026

RESUMO

The unreasonable misuse of antibiotics has led to the emergence of large-scale drug-resistant bacteria, seriously threatening human health. Compared with drug-sensitive bacteria, resistant bacteria are difficult to clear by host immunity. To fully explore the adaptive mechanism of resistant bacteria to the iron-restricted environment, we performed data-independent acquisition-based quantitative proteomics on ciprofloxacin (CIP)-resistant (CIP-R) Staphylococcus aureus in the presence or absence of iron. On bioinformatics analysis, CIP-R bacteria showed stronger amino acid synthesis and energy storage ability. Notably, CIP-R bacteria increased virulence by upregulating the expression of many virulence-related proteins and enhancing the synthesis of virulence-related amino acids under iron-restricted stress. This study will help us to further explain the adaptive mechanisms that lead to bacterial resistance to antibiotics depending on the host environment and provide insights into the development of novel drugs for the treatment of drug-resistant bacterial infections.


Assuntos
Ciprofloxacina , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ciprofloxacina/farmacologia , Humanos , Ferro , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Virulência
18.
Langmuir ; 37(13): 4016-4024, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33761744

RESUMO

The lithium-sulfur (Li-S) battery is an ideal electrochemical energy storage system owing to the high theoretical energy density and acceptable cost of finance and the environment. However, some disadvantages, including low electrical conductivity, poor sulfur utilization, and rapid capacity fading, obstruct its practical application. In this work, 3D carbon foam from a melamine resin is synthesized via high-temperature calcination. Carbon nanotubes (CNTs) and MnO2 are utilized to tailor the properties of the 3D cathode collector in the liquid Li2S6-containing Li-S battery without additional conductive agents, binders, and aluminum foil. Herein, the decorated MnO2 on the carbon fiber foam prolongs the lifespan of the Li-S battery, and adding CNTs is beneficial to enhance the capacity and cyclic performance of the Li-S battery under high sulfur loading. The Li-S battery with a sulfur loading of 3 mg cm-2 possesses a reversible capacity of 437.9 mA h g-1 after 400 cycles at 0.1 C. The capacity could be maintained at 568 mA h g-1 at 0.1 C after 80 cycles when the sulfur loading increases to 6 mg cm-2.

19.
Appl Opt ; 60(4): A62-A72, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690355

RESUMO

Laser inertial confinement fusion (ICF) triggers a nuclear fusion reaction via the evenly compressed capsule containing deuterium tritium fuel with a high-power laser. However, isolated defects on the surface of the capsules reduce the probability of ignition. In this paper, we present a full-surface defects detection method based on a null interferometric microscope (NIM) to achieve high-precision, high-efficiency, and full-surface defects detection on ICF capsules. A dynamic phase-shifting module is applied to the NIM to achieve a single-shot measurement in a single subaperture. With the capsule controlling system, the capsule is rotated and scanned along a planned lattice to get all subapertures measured. The eccentricity error can be measured from wavefront aberrations and compensated online to guarantee the measurement accuracy during the scanning process. After the scanning process, all of the surface defects are identified on the full-surface map. Theories and experimental results indicate that for the capsule with 875-µm-diameter, the lateral resolution could reach 0.7 µm and the measurement time is less than 1 h. The number of sampling points can reach about 50 million. To the best of our knowledge, our proposed system is the first to achieve full-surface defects detection of ICF capsules with such high efficiency and high resolution at the same time.

20.
Ecotoxicol Environ Saf ; 212: 111998, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540339

RESUMO

Metabolomics is an implement for testing the toxicity of antibiotics, and provides a comprehensive view of the overall response to stress; however, the connections between metabolites and biologic endpoints keep unclear in response to antibiotics. In this study, wheat seeds were exposed to tetracycline for 5 days. The results proved that tetracycline restrained growth, reduced chlorophyl and carotinoid contents and cell permeability, and increased reactive oxygen species (ROS) levels and malondialdehyde (MDA) content. Orthogonal partial least squares (OPLS) was used to analyze the connections between metabolites and biologic endpoints, which discovered that 11 metabolic pathways were significantly affected by tetracycline, and amino acid metabolism could largely apply to root growth and ROS accumulation, while carbohydrate metabolism could have a ruling effect on tetracycline-induced cell permeability. 13 metabolites all played active roles in mediating tetracycline's effects on root length, root fresh weight and cell permeability but had no significant effects on ROS levels. The majority of metabolites with passive effects on root length, root fresh weight and cell permeability had active effects on ROS levels. These results offer a view about stress reaction of wheat to tetracycline.


Assuntos
Antibacterianos/toxicidade , Redes e Vias Metabólicas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Tetraciclina/toxicidade , Triticum/efeitos dos fármacos , Análise dos Mínimos Quadrados , Malondialdeído/metabolismo , Metabolômica/métodos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
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