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1.
Sci Total Environ ; 927: 172258, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583618

RESUMO

Population outbreaks of the crown-of-thorns starfish (COTS) seriously threaten the sustainability of coral reef ecosystems. However, traditional ecological monitoring techniques cannot provide early warning before the outbreaks, thus preventing timely intervention. Therefore, there is an urgent need for a more accurate and faster technology to predict the outbreaks of COTS. In this work, we developed an electrochemical biosensor based on a programmed catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR) cyclic amplification strategy for sensitive and selective detection of COTS environmental DNA (eDNA) in water bodies. This biosensor exhibited excellent electrochemical characteristics, including a low limit of detection (LOD = 18.4 fM), low limit of quantification (LOQ = 41.1 fM), and wide linear range (50 fM - 10 nM). The biosensing technology successfully allowed the detection of COTS eDNA in the aquarium environment, and the results also demonstrated a significant correlation between eDNA concentration and COTS number (r = 0.990; P < 0.001). The reliability and accuracy of the biosensor results have been further validated through comparison with digital droplet PCR (ddPCR). Moreover, the applicability and accuracy of the biosensor were reconfirmed in field tests at the COTS outbreak site in the South China Sea, which has shown potential application in dynamically monitoring the larvae before the COTS outbreak. Therefore, this efficient electrochemical biosensing technology offers a new solution for on-site monitoring and early warning of the COTS outbreak.


Assuntos
Técnicas Biossensoriais , DNA Ambiental , Monitoramento Ambiental , Estrelas-do-Mar , Técnicas Biossensoriais/métodos , Animais , Monitoramento Ambiental/métodos , Recifes de Corais , China
2.
Subst Use Misuse ; : 1-8, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635979

RESUMO

BACKGROUND: Disability is associated with alcohol misuse and drug overdose death, however, its association with alcohol-induced death remains understudied. OBJECTIVE: To quantify the risk of alcohol-induced death among adults with different types of disabilities in a nationally representative longitudinal sample of US adults. METHODS: Persons with disabilities were identified among participants ages 18 or older in the Mortality Disparities in American Communities (MDAC) study (n = 3,324,000). Baseline data were collected in 2008 and mortality outcomes were ascertained through 2019 using the National Death Index. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were estimated for the association between disability type and alcohol-induced death, controlling for demographic and socioeconomic covariates. RESULTS: During a maximum of 12 years of follow-up, 4000 alcohol-induced deaths occurred in the study population. In descending order, the following disability types displayed the greatest risk of alcohol-induced death (compared to adults without disability): complex activity limitation (aHR = 1.7; 95% CI = 1.3-2.3), vision limitation (aHR = 1.6; 95% CI = 1.2-2.0), mobility limitation (aHR = 1.4; 95% CI = 1.3-1.7), ≥2 limitations (aHR = 1.4; 95% CI = 1.3-1.6), cognitive limitation (aHR = 1.2; 95% CI = 1.0-1.4), and hearing limitation (aHR = 1.0; 95% CI = 0.9-1.3). CONCLUSIONS: The risk of alcohol-induced death varies considerably by disability type. Efforts to prevent alcohol-induced deaths should be tailored to meet the needs of the highest-risk groups, including adults with complex activity (i.e., activities of daily living - "ALDs"), vision, mobility, and ≥2 limitations. Early diagnosis and treatment of alcohol use disorder within these populations, and improved access to educational and occupational opportunities, should be considered as prevention strategies for alcohol-induced deaths.

3.
Heliyon ; 10(6): e27956, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515703

RESUMO

Despite existing evidence linking dyskinesia to levodopa, the primary treatment for Parkinson's, the dose-response relationship and risk factors remain uncertain. In this study, the risk for dyskinesia in patients with Parkinson's disease receiving levodopa was evaluated via meta-analysis and meta-regression approaches to examine dyskinesia risk factors more reliably and improve treatment strategies and patient care. The PubMed and Embase databases were searched to identify randomized controlled trials comparing levodopa with other anti-Parkinson's drugs published in English before June 31, 2023. The primary outcome was dyskinesia, and a risk of bias assessment was performed. In total, 24 studies met the inclusion criteria; 21 had a low risk of bias, and 3 had a high risk of bias. These studies included 4698 patients with Hoehn and Yahr Grade I-III Parkinson's disease. Our meta-analysis showed that the risk of dyskinesia was higher for levodopa than for other anti-Parkinson's drugs (odds ratio: 2.52 [95% confidence interval: 1.84-3.46]). Dyskinesia was not related to age (slope coefficient: 0.185 [0.095]; P = 0.061), disease duration (slope coefficient: 0.011 [0.018]; P = 0.566), or treatment duration (slope coefficient: 0.008 [0.007]; P = 0.216). The mean levodopa equivalent dose (slope coefficient: 0.004 [0.001]; P = 0.001) in the experimental group and the differences in drug doses between the experimental and control groups were correlated with the risk of dyskinesia. Results of randomized controlled trials supported an association between the levodopa dose and dyskinesia in patients with Parkinson's disease. Compared with levodopa users, users of other anti-Parkinson's drugs had a lower incidence of dyskinesia. Age, disease duration, and treatment duration were not correlated with dyskinesia. These findings suggest that anti-Parkinson's drugs other than levodopa, particularly in cases of early-stage Parkinson's disease, should be considered to reduce the risk of dyskinesia.

4.
Int J Behav Med ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499962

RESUMO

BACKGROUND: Black sexual minority men (BSMM) are disproportionately vulnerable to HIV acquisition; the MPowerment model is one community-based framework for preventing HIV in this population. It focuses on developing a supportive network of peers to promote health messaging, reduce stigma, and improve resilience. While these interventions have demonstrated general success, there are important challenges related to race, sexuality, and internalized stigma. Our study aimed to explore these experiences among BSMM in MPowerment models focused on HIV prevention. METHOD: We conducted 24 qualitative interviews of BSMM attending HIV prevention-related MPowerment events in the greater D.C. Metropolitan area. In-depth interviews were conducted via phone, and interviews were analyzed using thematic analysis. RESULTS: We identified four themes from the transcript analysis process: Black queer intersectional social support and community, HIV-related information and destigmatization, social status, and sexuality. Within each of these themes, we identified relationships with overall HIV prevention messaging, including barriers to PrEP use. Barriers related to social status were especially prevalent and described as unique to the D.C. metropolitan area. CONCLUSION: Overall, MPowerment event spaces provide a forum for BSMM to feel safe and supported while gaining important HIV-related knowledge and prevention access. Challenges related to social status and destigmatization of sexuality are important considerations in designing and implementing this model, especially related to PrEP promotion.

5.
Bioelectrochemistry ; 158: 108697, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38554560

RESUMO

Heat stress and coral diseases are the predominant factors causing the degradation of coral reef ecosystems. Over recent years, Vibrio coralliilyticus was identified as a temperature-dependent pathogen causing tissue lysis in Pocillopora damicornis and one of the primary pathogens causing bleaching and mortality in other corals. Yet current detection techniques for V. coralliilyticus rely primarily on qPCR and ddPCR, which cannot meet the requirements for non-invasive and real-time detection. Herein, we developed an effective electrochemical biosensor modified by an Au-MoS2/rGO (AMG) nanocomposites and a specific capture probe to dynamically detect V. coralliilyticus environment DNA (eDNA) in aquarium experiments, with a lower limit of detection (0.28 fM) for synthetic DNA and a lower limit of quantification (9.8 fg/µL, ∼0.86 copies/µL) for genomic DNA. Its reliability and accuracy were verified by comparison with the ddPCR method (P > 0.05). Notably, coral tissue started to lyse at only 29 °C when the concentration of V. coralliilyticus increased abruptly to 880 copies/µL, indicating the biosensor could reflect the types of pathogen and health risks of corals under heat stress. Overall, the novel and reliable electrochemical biosensing technology provides an efficient strategy for the on-site monitoring and early warning of coral health in the context of global warming.

6.
Mol Plant ; 17(3): 496-508, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38341616

RESUMO

Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length changes. Seed weight is one of the key traits determining the soybean yield; however, the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly understood. In this study, we identify SW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1, an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit, as the causal gene of the SW19 locus. We showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in soybean. Further analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo, thus modulating seed weight under long days. However, Dt1 does not function in seed development under short days due to its very low expression. Importantly, we discovered a novel natural allelic variant of Dt1 (H4 haplotype) that decouples its pleiotropic effects on seed size and growth habit; i.e., this variant remains functional in seed development but fails to regulate the stem growth habit of soybean. Collectively, our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes, offering an ideal genetic component for improving soybean's yield by manipulating its seed weight and growth habit.


Assuntos
Soja , Fotoperíodo , Proteínas de Plantas , Sementes , Arabidopsis/metabolismo , Mapeamento Cromossômico , Soja/genética , Sementes/metabolismo , Sacarose/metabolismo , Proteínas de Plantas/metabolismo
7.
Plant Sci ; 342: 112035, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38367822

RESUMO

The post-translational modification (PTM) of proteins by ubiquitination modulates many physiological processes in plants. As the major protein degradation pathway in plants, the ubiquitin-proteasome system (UPS) is considered a promising target for improving crop tolerance drought, high salinity, extreme temperatures, and other abiotic stressors. The UPS also participates in abiotic stress-related abscisic acid (ABA) signaling. E3 ligases are core components of the UPS-mediated modification process due to their substrate specificity. In this review, we focus on the abiotic stress-associated regulatory mechanisms and functions of different UPS components, emphasizing the participation of E3 ubiquitin ligases. We also summarize and discuss UPS-mediated modulation of ABA signaling. In particular, we focus our review on recent research into the UPS-mediated modulation of the abiotic stress response in major crop plants. We propose that altering the ubiquitination site of the substrate or the substrate-specificity of E3 ligase using genome editing technology such as CRISPR/Cas9 may improve the resistance of crop plants to adverse environmental conditions. Such a strategy will require continued research into the role of the UPS in mediating the abiotic stress response in plants.


Assuntos
Resiliência Psicológica , Ubiquitina , Ubiquitina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Plantas/genética , Plantas/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Estresse Fisiológico/genética , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Sensors (Basel) ; 24(4)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38400337

RESUMO

Satellite clock error is a key factor affecting the positioning accuracy of a global navigation satellite system (GNSS). In this paper, we use a gated recurrent unit (GRU) neural network to construct a satellite clock bias forecasting model for the BDS-3 navigation system. In order to further improve the prediction accuracy and stability of the GRU, this paper proposes a satellite clock bias forecasting model, termed ITSSA-GRU, which combines the improved sparrow search algorithm (SSA) and the GRU, avoiding the problems of GRU's sensitivity to hyperparameters and its tendency to fall into local optimal solutions. The model improves the initialization population phase of the SSA by introducing iterative chaotic mapping and adopts an iterative update strategy based on t-step optimization to enhance the optimization ability of the SSA. Five models, namely, ITSSA-GRU, SSA-GRU, GRU, LSTM, and GM(1,1), are used to forecast the satellite clock bias data in three different types of orbits of the BDS-3 system: MEO, IGSO, and GEO. The experimental results show that, as compared with the other four models, the ITSSA-GRU model has a stronger generalization ability and forecasting effect in the clock bias forecasting of all three types of satellites. Therefore, the ITSSA-GRU model can provide a new means of improving the accuracy of navigation satellite clock bias forecasting to meet the needs of high-precision positioning.

9.
Sci Total Environ ; 918: 170663, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38311087

RESUMO

Arsenic (As) and cadmium (Cd) are two toxic metal(loid)s that pose significant risks to food security and human health. Silicon (Si) has attracted substantial attention because of its positive effects on alleviating the toxicity and accumulation of As and Cd in crops. However, our current knowledge of the comprehensive effects and detailed mechanisms of Si amendment is limited. In this study, a global meta-analysis of 248 original articles with over 7000 paired observations was conducted to evaluate Si-mediated effects on growth and As and Cd accumulation in rice (Oryza sativa L.), wheat (Triticum aestivum L.), and maize (Zea mays L.). Si application increases the biomass of these crops under As and/or Cd contamination. Si amendment also decreased shoot As and Cd accumulation by 24.1 % (20.6 to 27.5 %) and 31.9 % (29.0 to 31.9 %), respectively. Furthermore, the Si amendment reduced the human health risks posed by As (2.6 %) and Cd (12.9 %) in crop grains. Si-induced inhibition of Cd accumulation is associated with decreased Cd bioavailability and the downregulation of gene expression. The regulation of gene expression by Si addition was the driving factor limiting shoot As accumulation. Overall, our analysis demonstrated that Si amendment has great potential to reduce the toxicity and accumulation of As and/or Cd in crops, providing a scientific basis for promoting food safety globally.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Humanos , Grão Comestível/química , Cádmio/análise , Silício/farmacologia , Arsênio/metabolismo , Poluentes do Solo/análise , Solo , Oryza/metabolismo , Triticum/metabolismo
10.
Int J Biol Macromol ; 260(Pt 1): 129421, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228206

RESUMO

The quantitative analysis and spatial chemical visualization of amylopectin and amylose in different varieties of sweet potatoes were studied by merging spectral and image information. Three-dimensional (3D) hyperspectral images carrying 1D spectra and 2D images of hundreds of the samples (amylopectin, n = 644; amylose, n = 665) in near-infrared (NIR) range of 950-1650 nm (426 wavelengths) were acquired. The NIR spectra were mined to correlate with the values of the two indexes using a linear algorithm, generating a best performance with correlation coefficients and root mean square error of prediction (rP and RMSEP) of 0.983 and 0.847 g/100 mg for amylopectin, and 0.975 and 0.500 g/100 mg for amylose, respectively. Then, 14 % of the wavelengths (60 for amylopectin, 61 for amylopectin) were selected to simplify the prediction with rP and RMSEP of 0.970 and 1.103 g/100 mg for amylopectin, and 0.952 and 0.684 g/100 mg for amylose, respectively, comparable to those of full-wavelength models. By transferring the simplified model to original images, the color chemical maps were created and the differences of the two indexes in spatial distribution were visualized. The integration of NIR spectra and 2D image could be used for the more comprehensive evaluation of amylopectin and amylose concentrations in sweet potatoes.


Assuntos
Ipomoea batatas , Solanum tuberosum , Amilopectina , Amilose/análise , Amido , Algoritmos
11.
Adv Mater ; 36(1): e2307925, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37742133

RESUMO

Adopting renewable electricity to produce "green" hydrogen has been a critical challenge because at a high current density the mass transfer capability of most catalytic electrodes deteriorates significantly. Herein, a unique lamellar fern-like alloy aerogel (LFA) electrode, showing a unique dynamically adaptive bubbling capability and can effectively avoid stress concentration caused by bubble aggregation is reported. The LFA electrode is intrinsically highly catalytic-active and shows a highly porous, resilient, hierarchically ordered, and well-percolated conductive network. It not only shows superior gas evacuation capability but also exhibits significantly improved stability at high current densities, showing the record lowest oxygen evolution reaction (OER) overpotential of 244 mV at 1000 mA cm-2 and stably over 6000 h. With the merits of mechanical robustness, excellent electron transport, and efficient bubble evacuation, LFA can be self-standing catalytic electrode and gas diffusion layers in anion-exchange-membrane water electrolysis (AEMWE), which can achieve 3000 mA cm-2 at a low voltage of 1.88 V and can sustain stable electrolysis at 2000 mA cm-2 for over 1300 h. This strategy can be extended to various gas evolution reactions as a general design rule for multiphase catalysis applications.

12.
Pest Manag Sci ; 80(2): 473-497, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37794582

RESUMO

BACKGROUND: We designed an umbrella wind-field-type anti-drift spraying device to improve droplet deposit in the fruit tree canopy, reduce spray drift between fruit tree rows, and avoid uneven droplet deposit in the canopy. RESULTS: We used Computational Fluid Dynamics combined with wind field tests to optimize the parameters of the anti-drift spray device, and the results showed that airflow velocity at the outlet of the device after optimization was 24.5 m s-1 , which is 48% higher than that before optimization (16.5 m s-1 ) airflow velocity. We designed wind tunnel tests and field tests to analyze the anti-drift characteristics of the anti-drift spraying device. Wind tunnel test results showed that the side airflow velocity, outlet diameter, spray distance, and spray drift ratio were correlated. The mathematical models established by vertical and horizontal multifactor orthogonal tests were significant (P < 0.05, R2 0.947, 0.878, respectively). The results of the field tests showed that side airflow, velocity spray pressure and outlet diameter had significant effects on the droplet deposit characteristics (in descending order: the side airflow velocity, spray pressure, and outlet diameter). The maximum droplet deposit was 6.34 µL cm-2 when the side airflow velocity was 2 m s-1 , the spray pressure was 0.4 MPa, and the outlet diameter was 70 mm2 . When the side airflow velocity exceeded 2 m s-1 , the outlet diameter and spray pressure had to be reduced to ensure better droplet deposit. CONCLUSION: The results indicated that the umbrella wind field could reduce spray drift and ineffective deposit in off-target areas and provides a reference for the comprehensive analysis of the spray drift deposit law. © 2023 Society of Chemical Industry.


Assuntos
Mariposas , Praguicidas , Animais , Agricultura/métodos , Tamanho da Partícula , Modelos Teóricos , Praguicidas/análise
13.
Sci Total Environ ; 912: 168994, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38043809

RESUMO

Heavy metal(loid) (HM) pollution of agricultural soils is a growing global environmental concern that affects planetary health. Numerous studies have shown that soil microbial consortia can inhibit the accumulation of HMs in crops. However, our current understanding of the effects and mechanisms of inhibition is fragmented. In this review, we summarise extant studies and knowledge to provide a comprehensive view of HM toxicity on crop growth and development at the biological, cellular and the molecular levels. In a meta-analysis, we find that microbial consortia can improve crop resistance and reduce HM uptake, which in turn promotes healthy crop growth, demonstrating that microbial consortia are more effective than single microorganisms. We then review three main mechanisms by which microbial consortia reduce the toxicity of HMs to crops and inhibit HMs accumulation in crops: 1) reducing the bioavailability of HMs in soil (e.g. biosorption, bioaccumulation and biotransformation); 2) improving crop resistance to HMs (e.g. facilitating the absorption of nutrients); and 3) synergistic effects between microorganisms. Finally, we discuss the prospects of microbial consortium applications in simultaneous crop safety production and soil remediation, indicating that they play a key role in sustainable agricultural development, and conclude by identifying research challenges and future directions for the microbial consortium to promote safe crop production.


Assuntos
Metais Pesados , Poluentes do Solo , Solo , Consórcios Microbianos , Poluentes do Solo/análise , Metais Pesados/análise , Produtos Agrícolas/metabolismo , Produção Agrícola
14.
Prev Med ; 178: 107799, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070712

RESUMO

BACKGROUND: Disability is associated with increased risk of drug overdose mortality, but previous studies use coarse and inconsistent methods to identify adults with disabilities. This investigation makes use of the U.S. Department of Health and Human Services disability questions to estimate the risk of drug overdose death among U.S. adults using seven established disability categories. METHODS: The longitudinal Mortality Disparities in American Communities study was used to determine disability status among a nationally representative sample of adults age ≥18 in 2008 (n = 3,324,000). Through linkage to the National Death Index, drug overdose deaths were identified through 2019. Adults in mutually-exclusive disability categories (hearing, vision, cognitive, mobility, complex activity, ≥2 limitations) were compared to adults with no reported disabilities using adjusted hazard ratios (aHRs) and controlling for demographic and socioeconomic covariates. RESULTS: The risk of drug overdose death varied considerably by disability type, as adults in some disability categories displayed only marginally significant risk, while adults in other disability categories displayed substantially elevated risk. Compared to non-disabled adults, the risk of drug overdose death was highest among adults with ≥2 limitations (aHR = 3.0, 95% CI = 2.8-3.3), cognitive limitation (aHR = 2.6, 95% CI = 2.3-2.9), mobility limitation (aHR = 2.6, 95% CI = 2.3-2.9), complex activity limitation (aHR = 2.3, 95% CI = 1.8-2.9), hearing limitation (aHR = 1.6, 95% CI = 1.3-1.9), and vision limitation (aHR = 1.3, 95% CI = 1.0-1.7). CONCLUSIONS: The examination of specific disability categories revealed unique associations that were not apparent in previous research. These findings can be used to focus overdose prevention efforts on the populations at greatest risk for drug-related mortality.


Assuntos
Pessoas com Deficiência , Overdose de Drogas , Adulto , Humanos , Estados Unidos/epidemiologia , Estudos Longitudinais , Modelos de Riscos Proporcionais
15.
Angew Chem Int Ed Engl ; 62(50): e202315817, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37885150

RESUMO

Inorganic Bi-based perovskites have shown great potential in X-ray detection for their large absorption to X-rays, diverse low-dimensional structures, and eco-friendliness without toxic metals. However, they suffer from poor carrier transport properties compared to Pb-based perovskites. Here, we propose a mixed-halogen strategy to tune the structural dimensions and optoelectronic properties of Cs3 Bi2 I9-n Brn (0≤n≤9). Ten centimeter-sized single crystals are successfully grown by the Bridgman technique. Upon doping bromine to zero-dimensional Cs3 Bi2 I9 , the crystal transforms into a two-dimensional structure as the bromine content reaches Cs3 Bi2 I8 Br. Correspondingly, the optoelectronic properties are adjusted. Among these crystals, Cs3 Bi2 I8 Br exhibits negligible ion migration, moderate resistivity, and the best carrier transport capability. The sensitivities in 100 keV hard X-ray detection are 1.33×104 and 1.74×104  µC Gyair -1 cm-2 at room temperature and 75 °C, respectively, which are the highest among all reported bismuth perovskites. Moreover, the lowest detection limit of 28.6 nGyair s-1 and ultralow dark current drift of 9.12×10-9  nA cm-1 s-1 V-1 are obtained owing to the high ionic activation energy. Our work demonstrates that Br incorporation is an effective strategy to enhance the X-ray detection performance by tuning the dimensional and optoelectronic properties.

16.
Opt Express ; 31(19): 30184-30193, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710566

RESUMO

LiB3O5 (LBO) crystal has a very high bulk laser damage threshold. Laser damage often occurs on the surfaces with a large number of processing defects during application. In this paper, the surface laser damage threshold, damage growth threshold, and damage growth curve of LBO crystal and fused silica under the same processing process have been comparatively studied by using a 355 nm pulsed laser. The surface laser damage performance of LBO crystal has been comprehensive evaluated. The results show that the laser damage threshold and damage growth threshold of LBO are about twice that of fused silica, and the damage growth coefficient is about 0.7 times that of fused silica. The detection and analysis of impurity defects and photothermal weak absorption defects show that the subsurface defects of LBO crystal are less than that of fused silica. Laser damage morphologies show that the damage process is related to strongly bonded chemical structure and anisotropic physical characteristics of LBO crystal. These characteristics together determine the high threshold damage performance of LBO crystal. The results of this study are of great guidance for the application of LBO crystal in high-power laser systems.

17.
J Acquir Immune Defic Syndr ; 94(5): 387-394, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37732879

RESUMO

BACKGROUND: The COVID-19 pandemic has created substantial and profound barriers to several forms of health care engagement. For Black sexual minority men, this may include engagement with pre-exposure prophylaxis (PrEP) to prevent HIV infection, with significant implications for HIV disparities. Our study explored how the COVID-19 pandemic affected Black sexual minority men, with a focus on relationships between COVID-19 and PrEP engagement. SETTING: We sampled 24 Black sexual minority men attending HIV prevention-related events in the greater D.C. Metropolitan area (D.C., Maryland, Virginia). METHODS: We conducted qualitative phone interviews among our sample. Questions were primarily focused on the COVID-19 pandemic and how it affected engagement and considerations of PrEP use. Interviews were transcribed and qualitatively analyzed using the 6 stages of thematic analysis. RESULTS: We identified 3 major themes from our thematic analysis: Changes in the health care system, changes in sexual and relationship contexts, and COVID-19 vaccine hesitancy and misinformation. Relationships between COVID-19 vaccine hesitancy and PrEP hesitancy were especially prevalent, with participants describing that COVID-19 hesitancy can directly deter PrEP use through eroding medical trust further. CONCLUSIONS: We identified changes in the health care system, sexual and relationship contexts, and COVID-19 vaccine hesitancy as important issues driven by COVID-19 with significant implications for PrEP use. The COVID-19 pandemic has changed the health care and social landscape in profound ways that affect PrEP access, sexual networks, and associated HIV vulnerability. Future research further exploring relationships between specific pandemic stressors and HIV prevention among Black sexual minority men is recommended .


Assuntos
Fármacos Anti-HIV , COVID-19 , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina , Vacinas contra COVID-19 , Hesitação Vacinal , Pandemias/prevenção & controle , Fármacos Anti-HIV/uso terapêutico , COVID-19/prevenção & controle
18.
Front Endocrinol (Lausanne) ; 14: 1195658, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37538787

RESUMO

Background: Previous experimental studies have shown that mice overexpressing amyloid precursor protein, in which ß-amyloid (Aß) is overproduced, exhibit peripheral insulin resistance, pancreatic impairment, and hyperglycemia. We aimed to explore the effects of Aß on insulin action and insulin secretion in vitro and the association of plasma Aß with prediabetes in human. Methods: We examined the effects of Aß40 and Aß42 on insulin-inhibited glucose production in HepG2 cells, insulin-promoted glucose uptake in C2C12 myotubes, and insulin secretion in INS-1 cells. Furthermore, we conducted a case-control study (N = 1142) and a nested case-control study (N = 300) within the prospective Tongji-Ezhou cohort. Odds ratios (ORs) and 95% confidence intervals (CIs) for prediabetes were estimated by using conditional logistic regression analyses. Results: In the in vitro studies, Aß40 and Aß42 dose-dependently attenuated insulin-inhibited glucose production in HepG2 cells, insulin-promoted glucose uptake in C2C12 myotubes, and basal and glucose-stimulated insulin secretion in INS-1 cells. In the case-control study, plasma Aß40 (adjusted OR: 2.00; 95% CI: 1.34, 3.01) and Aß42 (adjusted OR: 1.94; 95% CI: 1.33, 2.83) were positively associated with prediabetes risk when comparing the extreme quartiles. In the nested case-control study, compared to the lowest quartile, the highest quartile of plasma Aß40 and Aß42 were associated with 3.51-fold (95% CI: 1.61, 7.62) and 2.75-fold (95% CI: 1.21, 6.22) greater odds of prediabetes, respectively. Conclusion: Elevated plasma Aß40 and Aß42 levels were associated with increased risk of prediabetes in human subjects, which may be through impairing insulin sensitivity in hepatocytes and myotubes and insulin secretion in pancreatic ß-cells.


Assuntos
Resistência à Insulina , Estado Pré-Diabético , Humanos , Animais , Camundongos , Peptídeos beta-Amiloides/metabolismo , Estudos de Casos e Controles , Secreção de Insulina , Estudos Prospectivos , Insulina/metabolismo
19.
Animals (Basel) ; 13(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37627408

RESUMO

Humans overlap with Asian elephants, resulting in frequent costly human-elephant conflicts, which disturb and even threaten local residents. In this study, we treat provincial and national nature reserves where Asian elephants still exist and other alternative habitats suitable for Asian elephants in southern Yunnan, China, as ecological patches. By using this approach, we can treat the terrain and surface state factors that hinder the migration of Asian elephants as a form of ecological resistance surface. We can then use a circuit theory model and remote sensing data to construct an ecological network, which allows us to identify ecological corridors and ecological pinch points. Herein, the possible migration routes of wild Asian elephants were identified. The main results are as follows: (1) In the study area, dense forests with steep slopes and high altitudes, cultivated land, and building land have greater migration resistance, while the gently undulating shrubs, bamboo forests, and grasslands far away from the city have less migration resistance. (2) There are three ecological corridor groups in the study area, mainly composed of shrub and grassland. The ecological corridors identified in this paper are the most likely migration routes of wild Asian elephants in China, and areas with higher simulated current densities reflect a higher probability of Asian elephants passing through. (3) According to the analysis, the ecological pinch points in the study area are 602 km2 in total, and woodland and grassland account for 89.2% of the total ecological pinch area. The areas where the pinch points are located have a high probability of Asian elephants passing through and a narrow space. Our findings can provide suggestions and solutions for the current conservation of wild Asian elephant species, alleviate human-elephant conflicts, promote the harmonious coexistence between humans and nature, and provide reference for biological protection and biological reserve planning.

20.
Bioelectrochemistry ; 154: 108541, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37579553

RESUMO

MiRNA-155 is a typical biomarker for breast cancer. Since its low concentration in the physiological environment and the limitations of conventional miRNA detection methods like Northern imprinting and RT-qPCR, convenient, real-time, and rapid detection methods are urgently needed. In this work, an electrochemical biosensor was constructed based on the flower-like MoSe2@1T-MoS2 heterojunction electrode material and specific RNA recognition probes, which can realize the rapid determination of miRNA-155 content with a wide detection range from 1 fM to 1 nM and a limit of detection (LOD) as low as 0.34 fM. Furthermore, the contents of miRNA-155 in blood samples of tumor-bearing mice and normal mice were measured as 724.93 pM and 21.42 pM, respectively by this biosensor, demonstrating its strong identification ability and miRNA-155 can be regarded as an ideal diagnostic marker. On this basis, a portable sensor platform was designed for on-site detection simulation and showed good recovery efficiency from 95.80% to 98.69%. Meanwhile, compared with the standard detection method RT-qPCR, the accuracy and reliability of the biosensor were verified, indicating that the biosensor has the potential to provide point-of-care testing (POCT) for the early diagnosis of breast cancer.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Neoplasias , Animais , Camundongos , Molibdênio/química , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos , MicroRNAs/genética , Limite de Detecção , Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos
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