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1.
Small ; : e2309822, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396268

RESUMO

Fe─N─C is the most promising alternative to platinum-based catalysts to lower the cost of proton-exchange-membrane fuel cell (PEMFC). However, the deficient durability of Fe─N─C has hindered their application. Herein, a TiN-doped Fe─N─C (Fe─N─C/TiN) is elaborately synthesized via the sol-gel method for the oxygen-reduction reaction (ORR) in PEMFC. The interpenetrating network composed by Fe─N─C and TiN can simultaneously eliminate the free radical intermediates while maintaining the high ORR activity. As a result, the H2 O2 yields of Fe─N─C/TiN are suppressed below 4%, ≈4 times lower than the Fe─N─C, and the half-wave potential only lost 15 mV after 30 kilo-cycle accelerated durability test (ADT). In a H2 ─O2 fuel cell assembled with Fe─N─C/TiN, it presents 980 mA cm-2 current density at 0.6 V, 880 mW cm-2 peak power density, and only 17 mV voltage loss at 0.80 A cm-2 after 10 kilo-cycle ADT. The experiment and calculation results prove that the TiN has a strong adsorption interaction for the free radical intermediates (such as *OH, *OOH, etc.), and the radicals are scavenged subsequently. The rational integration of Fe single-atom, TiN radical scavenger, and highly porous network adequately utilize the intrinsic advantages of composite structure, enabling a durable and active Pt-metal-free catalyst for PEMFC.

2.
BMC Microbiol ; 24(1): 138, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658823

RESUMO

BACKGROUND: Co-infection with other pathogens in coronavirus disease 2019 (COVID-19) patients exacerbates disease severity and impacts patient prognosis. Clarifying the exact pathogens co-infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is premise of the precise treatment for COVID-19 patients. METHODS: Sputum samples were collected from 17 patients in the COVID-19 positive group and 18 patients in the COVID-19 negative group. DNA extraction was performed to obtain the total DNA. Sequencing analysis using 16S and ITS rRNA gene was carried out to analyze the composition of bacterial and fungal communities. Meanwhile, all the samples were inoculated for culture. RESULTS: We did not observe significant differences in bacterial composition between the COVID-19 positive and negative groups. However, a significantly higher abundance of Candida albicans was observed in the upper respiratory tract samples from the COVID-19 positive group compared to the COVID-19 negative group. Moreover, the Candida albicans strains isolated from COVID-19 positive group exhibited impaired secretion of aspartyl proteinases. CONCLUSION: COVID-19 positive patients demonstrate a notable increase in the abundance of Candida albicans, along with a decrease in the levels of aspartyl proteinases, indicating the alteration of microbiota composition of upper respiratory tract.


Assuntos
Bactérias , COVID-19 , Candida albicans , Microbiota , Sistema Respiratório , SARS-CoV-2 , Escarro , Humanos , COVID-19/microbiologia , COVID-19/virologia , Microbiota/genética , Masculino , Candida albicans/isolamento & purificação , Candida albicans/genética , Feminino , Escarro/microbiologia , Escarro/virologia , Pessoa de Meia-Idade , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Sistema Respiratório/microbiologia , Sistema Respiratório/virologia , Idoso , RNA Ribossômico 16S/genética , Adulto , Coinfecção/microbiologia , Coinfecção/virologia
3.
Gastric Cancer ; 27(1): 28-35, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985571

RESUMO

BACKGROUND: Gastric cancer (GC) accounts for the greatest disparity in cancer mortality between Black and White Americans. Although clinical trials have shown that Helicobacter pylori (Hp) treatment reduces risk of GC, Hp testing and treatment is not consistently performed in the US, and may offer an opportunity to improve survival. METHODS: In a diverse retrospective cohort of 99 GC cases diagnosed at Duke University from 2002-2020 (57% Black; 43% white), we examined the association of Hp testing and treatment prior to or at cancer diagnosis with overall survival using Cox regression analyses to calculate adjusted hazards ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Overall, 62% of patients were tested for Hp prior to or at GC diagnosis. Of those, 25% tested positive and were treated < 1 year prior to or at diagnosis, 15% tested positive and were treated ≥ 1 year prior to diagnosis, 6% tested positive without evidence of treatment, and 54% tested negative. Compared to never tested, Hp testing and treatment < 1 year prior to or at diagnosis was associated with a significantly reduced likelihood of death (HR 0.21, 95% CI 0.08-0.58). The benefit of any Hp test and treat prior to or at GC diagnosis was significant even among stage IV patients only (HR, 0.22; 95% CI 0.05-0.96). CONCLUSIONS: These findings support Hp testing and treatment for patients at risk of or diagnosed with GC, and suggest Hp treatment may provide an opportunity to reduce GC mortality disparities in the US.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/epidemiologia , Estudos Retrospectivos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/complicações , Modelos de Riscos Proporcionais
4.
Phys Chem Chem Phys ; 26(22): 16200-16206, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804194

RESUMO

Considering that the crystallographic characteristics of the Sb-rich secondary phase particles (SPPs) greatly affect the thermoelectric properties of Bi2Te3 based materials, it is of great significance to explore the mechanism behind the Sb-rich SPPs in the p-type (Bi, Sb)2Te3 material. Here a conventional TEM technique was used to characterize the composition, size and distribution of Sb-rich SPPs in a spark plasma sintered p-type (Bi, Sb)2Te3 alloy. The results indicated that two different morphologies of Sb-rich SPPs including elongated and circular Sb-rich SPPs were frequently observed. Combined with high-resolution transmission electron microscopy, this work provides atomic-scale evidence for the formation mechanism behind the Sb-rich SPPs in the (Bi, Sb)2Te3 material.

5.
Chem Soc Rev ; 52(17): 6139-6190, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37565571

RESUMO

Sustainable zinc-air batteries (ZABs) are considered promising energy storage devices owing to their inherent safety, high energy density, wide operating temperature window, environmental friendliness, etc., showing great prospect for future large-scale applications. Thus, tremendous efforts have been devoted to addressing the critical challenges associated with sustainable ZABs, aiming to significantly improve their energy efficiency and prolong their operation lifespan. The growing interest in sustainable ZABs requires in-depth research on oxygen electrocatalysts, electrolytes, and Zn anodes, which have not been systematically reviewed to date. In this review, the fundamentals of ZABs, oxygen electrocatalysts for air cathodes, physicochemical properties of ZAB electrolytes, and issues and strategies for the stabilization of Zn anodes are systematically summarized from the perspective of fundamental characteristics and design principles. Meanwhile, significant advances in the in situ/operando characterization of ZABs are highlighted to provide insights into the reaction mechanism and dynamic evolution of the electrolyte|electrode interface. Finally, several critical thoughts and perspectives are provided regarding the challenges and opportunities for sustainable ZABs. Therefore, this review provides a thorough understanding of the advanced sustainable ZAB chemistry, hoping that this timely and comprehensive review can shed light on the upcoming research horizons of this prosperous area.

6.
J Environ Manage ; 356: 120669, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520852

RESUMO

The objective of this review was to provide quantitative insights into algal growth and nutrient removal in anaerobic digestate. To synthesize the relevant literature, a meta-analysis was conducted using data from 58 articles to elucidate key factors that impact algal biomass productivity and nutrient removal from anaerobic digestate. On average, algal biomass productivity in anaerobic digestate was significantly lower than that in synthetic control media (p < 0.05) but large variation in productivity was observed. A mixed-effects multiple regression model across study revealed that biological or chemical pretreatment of digestate significantly increase productivity (p < 0.001). In contrast, the commonly used practice of digestate dilution was not a significant factor in the model. High initial total ammonia nitrogen suppressed algal growth (p = 0.036) whereas initial total phosphorus concentration, digestate sterilization, CO2 supplementation, and temperature were not statistically significant factors. Higher growth corresponded with significantly higher NH4-N and phosphorus removal with a linear relationship of 6.4 mg NH4-N and 0.73 mg P removed per 100 mg of algal biomass growth (p < 0.001). The literature suggests that suboptimal algal growth in anaerobic digestate could be due to factors such as turbidity, high free ammonia, and residual organic compounds. This analysis shows that non-dilution approaches, such as biological or chemical pretreatment, for alleviating algal inhibition are recommended for algal digestate treatment systems.


Assuntos
Amônia , Microalgas , Anaerobiose , Nutrientes , Biomassa , Fósforo , Nitrogênio
7.
Emerg Infect Dis ; 29(11): 2398-2400, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877674

RESUMO

We identified a novel ceftazidime/avibactam resistance mechanism in sequence type 11 Klebsiella pneumoniae carbapenemase 2-producing K. pneumoniae. Plasmid recombination and chromosomal integration formed a novel virulence plasmid and provided an additional promoter for blaSHV-12, leading to blaSHV-12 overexpression and ceftazidime/avibactam resistance. Genetic rearrangement contributed to convergence of hypervirulence and ceftazidime/avibactam resistance.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Humanos , Ceftazidima/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Klebsiella pneumoniae/genética , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico , Proteínas de Bactérias/genética , beta-Lactamases/genética , Testes de Sensibilidade Microbiana
8.
J Antimicrob Chemother ; 78(12): 2890-2894, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37875024

RESUMO

OBJECTIVES: To determine the genomic features of IMP-4-producing Klebsiella pneumoniae isolates recovered from paediatric patients and the transmission dynamics of blaIMP-4. METHODS: IMP-producing K. pneumoniae isolates were collected from paediatric patients in Shanghai Children's Medical Center from 2013 to 2020. WGS was performed for all isolates, and the complete genomes of three IMP-4-producing isolates were generated. The distribution of blaIMP-4-harbouring plasmids was determined, and a conjugation assay was employed to investigate the horizontal transfer of blaIMP-4-harbouring plasmids. RESULTS: We collected 21 blaIMP-carrying K. pneumoniae isolates, with IMP-4 (16/21, 76.2%) as the predominant subtype, followed by IMP-8 (n = 3) and IMP-26 (n = 2). IMP-4-producing isolates displayed a diverse population structure and all blaIMP-4 genes were located on plasmids, including IncN (n = 9), IncHI5 (n = 5), IncFII(K) (n = 1) and IncFII(pKP91) (n = 1), although only IncN plasmids were conjugative. Clonal transmission of ST101 strains carrying IncHI5 blaIMP-4-harbouring plasmids was observed, and the acquisition of blaIMP-4 by the international high-risk ST101 clone constituted a novel combination of ST101 clone and carbapenemase genes. Plasmid analysis demonstrated that the conjugal transfer of the IncHI5 blaIMP-4-harbouring plasmid might be blocked by the ST101 bacterial host. CONCLUSIONS: The horizontal transfer of IncN plasmids and clonal spread of the international high-risk ST101 clone facilitated the nosocomial dissemination of blaIMP-4 among K. pneumoniae. The emerging IMP-4-producing ST101 clone displays diverse combinations of carbapenemase genes, and this clone could be a continually evolving threat and warrants prospective monitoring.


Assuntos
Infecção Hospitalar , Infecções por Enterobacteriaceae , Infecções por Klebsiella , Humanos , Criança , Klebsiella pneumoniae/genética , Infecções por Enterobacteriaceae/microbiologia , Transferência Genética Horizontal , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Prospectivos , China/epidemiologia , beta-Lactamases/genética , Plasmídeos/genética , Proteínas de Bactérias/genética , Infecções por Klebsiella/epidemiologia , Testes de Sensibilidade Microbiana , Antibacterianos
9.
Cancer Causes Control ; 34(10): 897-907, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37310566

RESUMO

PURPOSE: Gastric cancer remains a racial health disparity in the US, but few studies have examined supplements as a potential protective factor. We examined associations between regular supplement use and gastric cancer risk among the predominantly Black participants in the Southern Community Cohort Study (SCCS). METHODS: Of the 84,508 individuals recruited in the SCCS from 2002 to 2009, 81,884 responded to the baseline question: any vitamin or supplement taken at least once per month in the past year. Secondary analyses assessed specific supplement use. Associations with incident gastric cancer were examined using adjusted Cox proportional hazards models, stratified by histologic subtype and secondarily by healthy eating index (HEI). RESULTS: Approximately half of the participants (47%, n = 38,318) reported any regular supplement use. Among the 203 incident gastric cancers over the follow-up period (median, 7 years), 142 were non-cardia (NCGC), 31 cardia (CGC), and 30 unknown. Regular supplement use was associated with a 30% decreased risk of NCGC (hazards ratio (HR) 0.70; 95% confidence interval (CI) 0.49-0.99). Among participants below the HEI median, any regular supplement and multivitamin use were associated with a 52% and 70% decrease in risk of NCGC (HR 0.48; 95%CI 0.25-0.92 and HR 0.30; 95%CI 0.13-0.71), respectively. No associations were found for CGC. CONCLUSION: Regular supplement use, including multivitamins, was associated with a decreased risk of NCGC in the SCCS, particularly among participants with a lower quality diet. Inverse associations of supplement use and NCGC incidence provide support for clinical trials among high-risk populations in the US.


Assuntos
Neoplasias Gástricas , Humanos , Estudos de Coortes , Neoplasias Gástricas/epidemiologia , Suplementos Nutricionais , Fatores de Risco , Vitaminas
10.
BMC Microbiol ; 23(1): 130, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183254

RESUMO

BACKGROUND: Atopic dermatitis (AD) is an inflammatory skin condition distinguished by an activated Th2 immune response. The local skin microbial dysbiosis is a contributing factor to the development of AD. The pathogenic coagulase-positive Staphylococcus aureus is the primary species responsible for the progression of AD. Even though Staphylococcus pseudintermedius is an animal-origin pathogen, it is increasingly becoming a source of concern in human diseases. As another coagulase-positive Staphylococci, it is crucial to pay more attention to S. pseudintermedius isolated from the lesion site. RESULTS: In our investigation, we presented a case of cheilitis in a patient with atopic dermatitis (AD). We utilized culture and next-generation genomic sequencing (NGS) to identify the bacteria present on the skin swabs taken from the lip sites both prior to and following treatment. Our findings indicated that the predominant bacteria colonizing the lesion site of AD were S. pseudintermedius and S. aureus, both of which were eradicated after treatment. The Multi-locus sequence typing (MLST) of S. pseudintermedius and S. aureus demonstrated coordinated antibiotic susceptibility, with ST2384 and ST22 being the respective types. Although the skin abscess area resulting from S. pseudintermedius infection was significantly smaller than that caused by S. aureus in mice, the expression of cytokines interleukin-4 (IL-4) and interleukin-5 (IL-5) were significantly higher in the S. pseudintermedius-infected mice. CONCLUSIONS: The S. pseudintermedius strain isolated from the lesion site of the AD patient exhibited a higher expression of IL-4 and IL-5 when colonized on mouse skin, as compared to S. aureus. This observation confirms that S. pseudintermedius can effectively induce the Th2 response in vivo. Our findings suggest that animal-origin S. pseudintermedius may play a role in the development of AD when colonized on the skin, emphasizing the importance of taking preventive measures when in contact with animals.


Assuntos
Queilite , Coinfecção , Dermatite Atópica , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Staphylococcus aureus/fisiologia , Dermatite Atópica/complicações , Dermatite Atópica/microbiologia , Interleucina-4 , Interleucina-5 , Tipagem de Sequências Multilocus , Queilite/complicações , Queilite/patologia , Coagulase , Infecções Estafilocócicas/complicações , Pele/microbiologia
11.
Phys Chem Chem Phys ; 25(47): 32578-32583, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37999744

RESUMO

Twin boundaries provide a strong phonon scattering center to hinder the lattice thermal conductivity in thermoelectric materials, but the underlying evolution process of deformation twinning remains to be figured out. By applying atomic resolution transmission electron microscope (TEM) observations, a novel type of transitional structure of {0001} twin was observed, for the first time, in the p-type (Bi,Sb)2Te3 alloy subjected to three-point bending deformation. The transformation from matrix to (0001) twin can be realized by the following path: matrix → transitional twin → (0001) twin, and this process was completed by the gliding of a total of four partial dislocations (b1 = 1/3[011̄0]) extended in the different (0001) planes. This new finding here will shed light on the nucleation and growth of deformation twins in the p-type (Bi, Sb)2Te3 alloy.

12.
J Environ Manage ; 300: 113787, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34649312

RESUMO

Poultry litter waste is typically land-applied as a soil amendment but repeated application in the vicinity of poultry houses has led to phosphorus accumulation in soil. Such application can also lead to runoff that causes eutrophication. Most farmers store litter under dry conditions or compost the litter prior to land application, but it is not clear if these approaches are best from a nutrient management-perspective. The objective of this study was to investigate the effects of moisture content and active aeration on soluble mineral forms of nitrogen and phosphorus in poultry litter incubated for roughly one month. Mineral forms of nutrients are immediately plant-available upon field application and also most conducive to low-cost stripping and recovery methods. Litters were incubated at 50% and 70% moisture content with and without active aeration. Litter aeration led to significant ammonia losses and a consequent decline in litter pH but it had no effect on phosphate solubility. Moisture content during litter incubation governed the levels of plant-available phosphate and nitrification. High (70%) moisture led to 41%-78% higher plant-available phosphate (4.2-4.8 mg/g litter) compared to litters with 50% moisture content (2.7-3.0 mg/g litter). In contrast, the 50% moisture litters experienced 5-6 fold higher levels of nitrification (0.11-0.12 mg NO3-N/g litter) than litters with 70% moisture content (0.02 mg NO3-N/g litter), regardless of aeration. The implication is that lower-moisture litter storage is likely best for field application because phosphate is less soluble under neutral-alkaline conditions and therefore less likely to end up in runoff. In contrast, higher-moisture litter storage may be amenable to low-cost processes to leach and recover phosphate from litter.


Assuntos
Esterco , Aves Domésticas , Animais , Minerais , Nutrientes , Fósforo , Solubilidade
13.
Small ; 16(24): e2001571, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32390233

RESUMO

Due to the earth abundance and tunable electronic properties, etc., transition metal oxides (TMOs) show attractive attention in oxygen evolution reaction. O-vacancies (Vo ) play important roles in tailoring the local surface and electronic environment to lower the activation barriers. Herein, an effective strategy is shown to enhance the oxygen evolution reduction (OER) performance on Co3 O4 ultrathin nanosheets via combined cation substitution and anion vacancies. The oxygen-deficient Fe-Co-O nanosheets (3-4 nm thickness) display an overpotential of 260 mV@10 mA cm-2 and a Tafel slope of 53 mV dec-1 , outperforming those of the benchmark RuO2 in 1.0 m KOH. Further calculations demonstrate that the combined introduction of Fe cation and Vo with appropriate location and content finely tune the intermediate absorption, consequently lowering the rate-limiting activation energy from 0.82 to as low as 0.15 eV. The feasibility is also proved by oxygen-deficient Ni-Co-O nanosheets. This work not only establishes a clear atomic-level correlation between cation substitution, anion vacancies, and OER performance, but also provides valuable insights for the rational design of highly efficient catalysts for OER.

14.
Angew Chem Int Ed Engl ; 59(3): 1295-1301, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31654544

RESUMO

It is highly desirable but challenging to optimize the structure of photocatalysts at the atomic scale to facilitate the separation of electron-hole pairs for enhanced performance. Now, a highly efficient photocatalyst is formed by assembling single Pt atoms on a defective TiO2 support (Pt1 /def-TiO2 ). Apart from being proton reduction sites, single Pt atoms promote the neighboring TiO2 units to generate surface oxygen vacancies and form a Pt-O-Ti3+ atomic interface. Experimental results and density functional theory calculations demonstrate that the Pt-O-Ti3+ atomic interface effectively facilitates photogenerated electrons to transfer from Ti3+ defective sites to single Pt atoms, thereby enhancing the separation of electron-hole pairs. This unique structure makes Pt1 /def-TiO2 exhibit a record-level photocatalytic hydrogen production performance with an unexpectedly high turnover frequency of 51423 h-1 , exceeding the Pt nanoparticle supported TiO2 catalyst by a factor of 591.

15.
BMC Med Imaging ; 19(1): 12, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683072

RESUMO

BACKGROUND: Fetal deformity is a disease caused by abnormal chromosome structure, which may be influenced by genetic factors as well as the maternal and external environment. Magnetic resonance imaging (MRI) may be used to effectively diagnose fetus deformities. However it has been reported that gene analysis is a more accurate diagnostic method. The aim of the present study was to investigate the effectiveness of MRI in combination with gene analysis for the diagnosis of fetal congenital heart disease, a form of fetus deformity. METHODS: MRI, array comparative genome hybridization analysis and fluorescence in situ hybridization were used to analyze the effectiveness of the two methods in a total of 78 pregnant women with suspected fetal congenital heart disease. RESULTS: Our findings demonstrated that the combination of MRI and gene analysis resulted in significantly improved diagnostic accuracy, sensitivity and specificity for fetal congenital heart disease compared with either method alone. MRI combined with gene analysis confirmed 42 fetuses with pulmonary stenosis, 24 with aortic stenosis and 12 healthy fetuses, which was significantly improved compared with MRI or gene analysis alone. It was also observed that gene analysis was a more efficient method of diagnosis compared with MRI; however, the combination of the two methods was the most effective. CONCLUSION: In conclusion, the results of the present study suggest that MRI combined with gene analysis may be a more effective diagnostic method for fetal congenital heart disease compared with the current protocol.


Assuntos
Hibridização Genômica Comparativa/métodos , Cardiopatias Congênitas/diagnóstico , Hibridização in Situ Fluorescente/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Estenose da Valva Aórtica/congênito , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/genética , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Cardiopatias Congênitas/genética , Humanos , Idade Materna , Gravidez , Estenose da Valva Pulmonar/congênito , Estenose da Valva Pulmonar/diagnóstico por imagem , Estenose da Valva Pulmonar/genética , Sensibilidade e Especificidade , Adulto Jovem
16.
Behav Sci (Basel) ; 14(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38247669

RESUMO

Parental burnout refers to exhaustion caused by the parenting role. This devastating negative emotion can have repercussions for adolescent social development. Nevertheless, much remains unclear about the association between parental burnout and adolescent prosocial behavior and the potential mechanisms underlying this relationship. Based on theoretical and empirical evidence, the current study examined the relationship between parental burnout and adolescent prosocial behavior by using a sequential mediation model that included both parental empathy and adolescent empathy as potential mediators. A total of 488 parent-adolescent dyads (for adolescents: 45.7% men, 54.3% women, Mage = 15.28 ± 1.67 years; for parents: 36.5% fathers, 63.5% mothers, Mage = 41.30 ± 3.79 years) completed questionnaires regarding demographics, social desirability, parental burnout, parental empathy, adolescent empathy, and adolescent prosocial behavior. After controlling for demographic covariates and social desirability, the results showed that parental burnout had a negative effect on adolescent-reported prosocial behavior through parental cognitive empathy and adolescent other-oriented empathy (adolescent cognitive empathy and empathic concern) sequentially. These findings contribute to our understanding of the role of parental burnout as a family environmental factor detrimental to the positive functioning of adolescents through parental reactions to their children's emotions and children's own social competence.

17.
ACS Nano ; 17(10): 9565-9574, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37158422

RESUMO

Robust operation of Zn-air batteries (ZABs) with high capacity and excellent energy efficiency is desirable for practical harsh applications, whose bottlenecks are mainly originated from the sluggish oxygen catalytic kinetics and unstable Zn|electrolyte interface. In this work, we synthesized the edge-hosted Mn-N4-C12 coordination supported on N-doped defective carbon (Mn1/NDC) catalyst, exhibiting a good bifunctional performance of the oxygen reduction/evolution reaction (ORR/OER) with a low potential gap of 0.684 V. Theoretical calculation reveals that the edge-hosted Mn-N4-C12 coordination displayed the lowest overpotential of the ORR/OER owing to the decreased adsorption free energy of OH*. The Mn1/NDC-based aqueous ZABs deliver impressive rate performance, ultralong discharging lifespan, and excellent stability. Notably, the assembled solid-state ZABs demonstrate a high capacity of 1.29 Ah, a large critical current density of 8 mA cm-2, and robust cycling stability with excellent energy efficiency at -40 °C, which should be attributed to the good bifunctional performance of Mn1/NDC and anti-freezing solid-state electrolyte (SSE). Meanwhile, the zincophilic nanocomposite SSE with high polarity accounts for the stable Zn|SSE interface compatibility. This work not only highlights the importance of the atomic structure design of oxygen electrocatalysts for ultralow-temperature and high-capacity ZABs but also spurs the development of sustainable Zn-based batteries at harsh conditions.

18.
ACS Omega ; 8(20): 17712-17718, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37251147

RESUMO

Staphylococcus aureus is a high-virulent Gram-positive pathogen that is responsible for a serious of diseases. The emergence of antibiotic-resistant S. aureus poses a significant challenge in terms of treatment. The recent research on the human microbiome suggested that the application of commensal bacteria is a new strategy for combating pathogenic infections. Staphylococcus epidermidis, one of the most abundant species in the nasal microbiome, is able to inhibit the colonization of S. aureus. However, during bacterial competition, S. aureus undergoes evolutionary changes to adapt to the diverse environment. Our study has demonstrated that the nasal colonized S. epidermidis possesses the ability to inhibit the hemolytic activity of S. aureus. Moreover, we deciphered another layer of mechanism to inhibit S. aureus colonization by S. epidermidis. The active component present in the cell-free culture of S. epidermidis was found to significantly reduce the hemolytic activity of S. aureus in SaeRS- and Agr-dependent manner. Specifically, the hemolytic inhibition on the S. aureus Agr-I type by S. epidermidis is primarily dependent on the SaeRS two-component system. The active component is characterized as a small molecule that is heat sensitive and protease resistant. Critically, S. epidermidis significantly inhibit the virulence of S. aureus in a mouse skin abscess model, suggesting that the active compound could potentially be used as a therapeutic agent for managing S. aureus infections.

19.
Emerg Microbes Infect ; 12(2): 2276335, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37882148

RESUMO

Diabetic foot infections are a common complication of diabetes. Staphylococcus aureus is frequently isolated from diabetic foot infections and commonly colonizes human nares. According to the study, the nasal microbiome analysis revealed that diabetic patients had a significantly altered nasal microbial composition and diversity. Typically, the fasting blood glucose (FBG) level had an impact on the abundance and sequence type (ST) of S. aureus in diabetic patients. We observed that highly virulent S. aureus ST7 strains were more frequently colonized in diabetic patients, especially those with poorly controlled FBG, while ST59 was dominant in healthy individuals. S. aureus ST7 strains were more resistant to human antimicrobial peptides and formed stronger biofilms than ST59 strains. Critically, S. aureus ST7 strains displayed higher virulence compared to ST59 strains in vivo. The dominance of S. aureus ST7 strains in hyperglycemic environment is due to the higher activity of the SaeRS two-component system (TCS). S. aureus ST7 strains outcompeted ST59 both in vitro, and in nasal colonization model in diabetic mice, which was abolished by the deletion of the SaeRS TCS. Our data indicated that highly virulent S. aureus strains preferentially colonize diabetic patients with poorly controlled FBG through SaeRS TCS. Detection of S. aureus colonization and elimination of colonizing S. aureus are critical in the care of diabetic patients with high FBG.


Assuntos
Diabetes Mellitus Experimental , Pé Diabético , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Staphylococcus aureus , Diabetes Mellitus Experimental/complicações , Nariz , Cavidade Nasal
20.
Polymers (Basel) ; 14(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35335405

RESUMO

Geopolymers may be the best alternative to ordinary Portland cement because they are manufactured using waste materials enriched in aluminosilicate. Research on geopolymer composites is accelerating. However, considerable work, expense, and time are needed to cast, cure, and test specimens. The application of computational methods to the stated objective is critical for speedy and cost-effective research. In this study, supervised machine learning approaches were employed to predict the compressive strength of geopolymer composites. One individual machine learning approach, decision tree, and two ensembled machine learning approaches, AdaBoost and random forest, were used. The coefficient correlation (R2), statistical tests, and k-fold analysis were used to determine the validity and comparison of all models. It was discovered that ensembled machine learning techniques outperformed individual machine learning techniques in forecasting the compressive strength of geopolymer composites. However, the outcomes of the individual machine learning model were also within the acceptable limit. R2 values of 0.90, 0.90, and 0.83 were obtained for AdaBoost, random forest, and decision models, respectively. The models' decreased error values, such as mean absolute error, mean absolute percentage error, and root-mean-square errors, further confirmed the ensembled machine learning techniques' increased precision. Machine learning approaches will aid the building industry by providing quick and cost-effective methods for evaluating material properties.

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