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1.
Plant Physiol Biochem ; 216: 109128, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39307106

RESUMO

Plant homeodomain (PHD) proteins are a family of zinc finger transcription factors that play roles in abiotic stress tolerance. However, their mechanisms in conferring salt tolerance are largely unknown. In this study, we characterized a PHD gene, PdbPHD3, from Populus davidiana × P. bolleana (Shanxin poplar) in response to salt stress. PdbPHD3 is a nuclear protein that is strongly induced by salt and abscisic acid (ABA) treatments. Overexpression of PdbPHD3 conferred salt tolerance, while silencing of PdbPHD3 increased sensitivity to salt. PdbPHD3 could enhance the activities of superoxide dismutase and peroxidase to reduce the abundance of reactive oxygen species, and enhance the osmotic potential by increasing the proline content. Chromatin immunoprecipitation sequencing (ChIP-seq) revealed that PdbPHD3 could bind to various DNA motifs, including the G-box ("CACGTG"), PALBOXAPC ("GGACGG"), and POLLEN1LELAT52 ("TTTCTT"). ChIP-seq combined with RNA sequencing identified a transcription factor gene, squamosa promoter binding protein 3 (PdbSBP3), which is directly regulated by PdbPHD3. Overexpression and silencing of PdbSBP3 improved and decreased salt tolerance, respectively. PdbSBP3 could also regulate all the physiological changes associated with salt tolerance, similar to PdbPHD3. These results suggest that PdbPHD3 confers salt tolerance by regulating PdbSBP3 to reduce ROS accumulation and increase proline content. Therefore, the regulatory axis of PdbPHD3 and PdbSBP3 confers salt tolerance in Shanxin poplar.

2.
Mar Pollut Bull ; 208: 116992, 2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39312813

RESUMO

Nutrient exchange with the East China Sea plays an important role in primary production in the Yellow Sea. Owing to lack of simultaneous observations, the spatiotemporal nutrient exchanges across the boundary between the Yellow Sea and East China Sea (Section YE) remain unclear. In this study, a three-dimensional physical-biogeochemical coupled model was used to determine the flux of dissolved inorganic nitrogen (DIN) across Section YE. The results showed that DIN was transported from the East China Sea to the Yellow Sea throughout the year and was highest in summer, accounting for 38 % of the total annual amount. Seasonal variations in the DIN flux were attributed to seasonal variations in the ocean currents across Section YE. In the Yellow Sea, the annual amount of DIN from lateral boundaries was larger than the river input and was comparable to the atmospheric deposition.

3.
J Photochem Photobiol B ; 259: 113023, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39241393

RESUMO

Pseudomonas aeruginosa, a notable pathogen frequently associated with hospital-acquired infections, displays diverse intrinsic and acquired antibiotic resistance mechanisms, posing a significant challenge in infection management. Antimicrobial blue light (aBL) has been demonstrated as a potential alternative for treating P. aeruginosa infections. In this study, we investigated the impact of blue light wavelength, bacterial growth stage, and growth medium composition on the efficacy of aBL. First, we compared the efficacy of light wavelengths 405 nm, 415 nm, and 470 nm in killing three multidrug resistant clinical strains of P. aeruginosa. The findings indicated considerably higher antibacterial efficacy for 405 nm and 415 nm wavelength compared to 470 nm. We then evaluated the impact of the bacterial growth stage on the efficacy of 405 nm light in killing P. aeruginosa using a reference strain PAO1 in exponential, transitional, or stationary phase. We found that bacteria in the exponential phase were the most susceptible to aBL, followed by the transitional phase, while those in the stationary phase exhibited the highest tolerance. Additionally, we quantified the production of reactive oxygen species (ROS) in bacteria using the 2',7'-dichlorofluorescein diacetate (DCFH-DA) probe and flow cytometry, and observed a positive correlation between aBL efficacy and ROS production. Finally, we determined the influence of growth medium on aBL efficacy. PAO1 was cultivated in brain heart infusion (BHI), Luria-Bertani (LB) broth or Casamino acids (CAA) medium, before being irradiated with aBL at 405 nm. The CAA-grown bacteria exhibited the highest sensitivity to aBL, followed by those grown in LB broth, and the BHI-grown bacteria demonstrated the lowest sensitivity. By incorporating FeCl3, MnCl2, ZnCl2, or the iron chelator 2,2'-bipyridine (BIP) into specific media, we discovered that aBL efficacy was affected by the iron levels in culture media.


Assuntos
Meios de Cultura , Luz , Pseudomonas aeruginosa , Espécies Reativas de Oxigênio , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Meios de Cultura/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Luz Azul
4.
Int J Biol Macromol ; 280(Pt 1): 135598, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276878

RESUMO

This study proposed a novel extraction method for soy protein isolate, which involved solid-state fermentation of high-temperature soybean meal. The proteinases secreted by microorganisms acted on the high-temperature soybean meal, making the SPI easier to extract. The study concludes that Bacillus amyloliquefaciens subsp. plantarum CICC 10265 could be used for solid-state fermentation of soybean meal, and the fermentation effect was good, with a yield of 41.91 % for SPI. Compared to the direct extraction of SPI from high-temperature soybean meal, the yield had increased by 130.19 %. Meanwhile, we also conducted research on the losses during the SPI extraction process. Through experiments, the study identified the patterns of protease activity changes and microbial colony growth during solid-state fermentation of soybean meal by Bacillus amyloliquefaciens subsp. plantarum CICC 10265. It was concluded that extracting SPI after 8 h of fermentation is more suitable. The experimental results indicated that the total amino acid content of SPI extracted from fermented soybean meal was 2.1 % higher compared to SPI extracted from low-temperature soybean meal. The extracted SPI also met the microbial standards.

5.
ACS Appl Mater Interfaces ; 16(36): 47879-47888, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39188162

RESUMO

In the image Gaussian filtering process, convolving with a Gaussian matrix is essential due to the numerous arithmetic computations involved, predominantly multiplications and additions. This can heavily tax the system's memory, particularly with frequent use. To address this issue, a W/Ta2O5/Ag memristor was employed to substantially mitigate the computational overhead associated with convolution operations. Additionally, an interlayer of ZnO was subsequently introduced into the memristor. The resulting Ta2O5/ZnO heterostructure layer exhibited improved linearity in the pulse response, which enhanced linearity facilitates easy adjustment of the conductance magnitude through a linear mapping of the number of pulses and the conductance. Subsequently, the conductance of the W/Ta2O5/ZnO/Ag bilayer memristor was employed as the weights for the convolution kernel in convolution operations. Gaussian noise removal in image processing was achieved by assembling a 5 × 5 memristor array as the kernel. When denoising was performed using memristor arrays, compared to denoising achieved through Gaussian matrix convolution, an average loss of less than 5% was observed. The provided memristors demonstrate significant potential in convolutional computations, particularly for subsequent applications in convolutional neural networks (CNNs).

6.
Toxics ; 12(8)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39195661

RESUMO

Glyphosate is the most widely used herbicide in the world. This study aimed to evaluate the relationships among urinary glyphosate, all-cause mortality and cardiovascular diseases (CVD)-related mortality in the general US population of adults, and to determine the role of alkaline phosphatase (ALP), an inflammation marker that is associated with glyphosate exposure, in these relationships. Subjects from the National Health and Nutrition Examination Survey (NHANES) 2013-2018 cycles were included. Survey-weighted Cox regression analysis was applied to estimate the relationship of glyphosate with overall and CVD mortalities. Restricted cubic spline (RCS) analysis was utilized to detect the linearity of associations. The intermediary role of ALP was explored by mediation analysis. Our results found consistent and positive associations of glyphosate with all-cause mortality (HR: 1.29, 95%CI: 1.05-1.59) and CVD mortality (HR: 1.32, 95%CI: 1.02-1.70). RCS curves further validated linear and positive dose-dependent relationships between glyphosate and mortality-related outcomes. Moreover, serum ALP was identified as a mediator in these associations and explained 12.1% and 14.0% of the total associations between glyphosate and all-cause death and CVD death risk, respectively. Our study indicated that glyphosate was associated with increased all-cause and CVD mortality in humans. Increased ALP may play an essential role in these associations.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39150801

RESUMO

Unsupervised Domain Adaptation (UDA) methods have been successful in reducing label dependency by minimizing the domain discrepancy between labeled source domains and unlabeled target domains. However, these methods face challenges when dealing with Multivariate Time-Series (MTS) data. MTS data typically originates from multiple sensors, each with its unique distribution. This property poses difficulties in adapting existing UDA techniques, which mainly focus on aligning global features while overlooking the distribution discrepancies at the sensor level, thus limiting their effectiveness for MTS data. To address this issue, a practical domain adaptation scenario is formulated as Multivariate Time-Series Unsupervised Domain Adaptation (MTS-UDA). In this paper, we propose SEnsor Alignment (SEA) for MTS-UDA, aiming to address domain discrepancy at both local and global sensor levels. At the local sensor level, we design endo-feature alignment, which aligns sensor features and their correlations across domains. To reduce domain discrepancy at the global sensor level, we design exo-feature alignment that enforces restrictions on global sensor features. We further extend SEA to SEA++ by enhancing the endo-feature alignment. Particularly, we incorporate multi-graph-based higher-order alignment for both sensor features and their correlations. Extensive empirical results have demonstrated the state-of-the-art performance of our SEA and SEA++ on six public MTS datasets for MTS-UDA.

8.
Methods Mol Biol ; 2846: 123-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39141233

RESUMO

DNA-protein interactions play fundamental roles in diverse biological functions. The gene-centered method is used to identify the upstream regulators of defined genes. In this study, we developed a novel method for capturing the proteins that bind to certain chromatin fragments or DNA sequences, which is called reverse chromatin immunoprecipitation (R-ChIP). This technology uses a set of specific DNA probes labeled with biotin to isolate chromatin or DNA fragments, and the DNA-associated proteins are then analyzed using mass spectrometry. This method can capture DNA-associated proteins with sufficient quantity and purity for identification.


Assuntos
Imunoprecipitação da Cromatina , Cromatina , DNA , Imunoprecipitação da Cromatina/métodos , Cromatina/metabolismo , Cromatina/genética , DNA/metabolismo , DNA/genética , Humanos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Espectrometria de Massas/métodos , Ligação Proteica , Sondas de DNA/genética
9.
Biomolecules ; 14(8)2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39199361

RESUMO

The kidney performs fundamental functions by eliminating metabolic waste and reabsorbing essential nutrients and electrolytes such as glucose, proteins, ions, and anions [...].


Assuntos
Nefropatias , Mitocôndrias , Oxirredução , Humanos , Mitocôndrias/metabolismo , Nefropatias/metabolismo , Nefropatias/patologia , Animais , Estresse Oxidativo , Rim/metabolismo , Rim/patologia
10.
Pestic Biochem Physiol ; 203: 106012, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39084804

RESUMO

Liriomyza trifolii, an invasive pest, poses a substantial threat to horticultural and vegetable plants. It spreads rapidly, especially in hot weather, leading to large-scale outbreaks with strong thermotolerance and insecticide resistance. In this study, mortality and LtCYP4g1 expression in L. trifolii were evaluated after thermal and insecticides exposure. Furthermore, functional verification of LtCYP4g1 was conducted through RNA interference and bacterial survival assays in Escherichia coli containing recombinant LtCYP4g1 protein. Results indicated that a short time exposure to high temperature incresed insecticide tolerance of L. trifolii, attributed to decreased mortality and induced LtCYP4g1 expression; LtCYP4g1 was involved in stimulating synthesis of cuticular hydrocarbons (CHCs) and elevating epicuticle lipid content and thickness, and E. coli cells overexpressing LtCYP4g1 exhibited significant tolerance to thermal and insecticide stress. In general, P450-mediated tolerance of L. trifolii was enhanced by high temperature, with LtCYP4g1 playing a role in promoting biosynthesis of CHCs for thickening epidermal lipid barrier and reducing cuticular penetration. This study provides a framework for delving into the function of CYP450s in insecticide detoxification and illustrates the role of global warming in driving the evolution of L. trifolii.


Assuntos
Sistema Enzimático do Citocromo P-450 , Inseticidas , Ivermectina , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Resistência a Inseticidas/genética , Hidrocarbonetos/metabolismo , Temperatura Alta , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Besouros/efeitos dos fármacos , Besouros/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
11.
Neurosurg Rev ; 47(1): 320, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002049

RESUMO

OBJECTIVE: Secretoneurin may play a brain-protective role. We aim to discover the relationship between serum secretoneurin levels and severity plus neurological outcome after intracerebral hemorrhage (ICH). METHODS: In this prospective cohort study, serum secretoneurin levels were measured in 110 ICH patients and 110 healthy controls. Glasgow Coma Scale (GCS) and hematoma volume were used to assess stroke severity. Poor prognosis was defined as Glasgow Outcome Scale (GOS) scores of 1-3 at 90 days after ICH. A multivariate logistic regression model was constructed to determine independent correlation of serum secretoneurin levels with severity and poor prognosis. Under receiver operating characteristic (ROC) curve, prognostic ability of serum secretoneurin levels was assessed. Restricted cubic spline (RCS) model and subgroups analysis were used for discovering association of serum secretoneurin levels with risk of poor prognosis. Calibration curve and decision curve were evaluated to confirm performance of nomogram. RESULTS: Serum secretoneurin levels of patients were significantly higher than those of healthy controls. Serum secretoneurin levels of patients were independently correlated with GCS scores and hematoma volume. There were 42 patients with poor prognosis at 90 days following ICH. Serum secretoneurin levels were significantly higher in patients with poor outcome than in those with good outcome. Under the ROC curve, serum secretoneurin levels significantly differentiated poor outcome. Serum secretoneurin levels ≥ 22.8 ng/mL distinguished patients at risk of poor prognosis at 90 days with a sensitivity of 66.2% and a specificity of 81.0%. Besides, serum secretoneurin levels independently predicted a 90-day poor prognosis. Subgroup analysis showed that serum secretoneurin levels had non-significant interactions with other variables. The nomogram, including independent prognostic predictors, showed reliable prognosis capability using calibration curve and decision curve. Area under the curve of the predictive model was significantly higher than those of GCS scores and hematoma volume. CONCLUSION: Serum secretoneurin levels are strongly related to ICH severity and poor prognosis at 90 days after ICH. Thus, serum secretoneurin may be a promising prognostic biomarker in ICH.


Assuntos
Biomarcadores , Hemorragia Cerebral , Humanos , Masculino , Hemorragia Cerebral/sangue , Hemorragia Cerebral/diagnóstico , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Biomarcadores/sangue , Estudos Prospectivos , Neuropeptídeos/sangue , Secretogranina II/sangue , Escala de Coma de Glasgow , Estudos de Coortes , Adulto , Curva ROC , Escala de Resultado de Glasgow
12.
J Hazard Mater ; 476: 135166, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38991635

RESUMO

Minimization of cadmium (Cd) accumulation in wheat grain (Triticum aestivum L.) is an important way to prevent Cd hazards to humans. However, little is known about the mechanisms of varietal variation of Cd accumulation in wheat grain. This study explores the physiological mechanisms of Cd bioaccumulation through field and hydroponic experiments on two wheat varieties of low-Cd-accumulating variety (L-6331) and high-Cd-accumulating variety (H-6049). Field study showed that average Cd accumulative rates in spikes of H-6049 were 1.57-fold of L-6331 after flowering, ultimately grain-Cd of H-6049 was 1.70-fold of L-6331 in Cd-contaminated farmland. The hydroponic experiment further confirmed that more vegetative tissues of L-6331 were involved in the remobilization of Cd, which jointly mitigated the process of Cd loaded to grains when leaf-cutting conducted after Cd stress. Additionally, the L1 and N1 of L-6331 play an especially important role in regulating Cd remobilization, and the larger EVB areas in N1 have the morphological feature that facilitates the transfer of Cd to L1. Overall results implied that low-Cd-accumulating variety initiated more trade-offs of reproductive growth and Cd remobilizatoin under Cd-stress after flowering compared with high-Cd-accumulating variety, and provided new insights into the processes of Cd loaded into wheat grains among different varieties.


Assuntos
Cádmio , Poluentes do Solo , Triticum , Triticum/metabolismo , Triticum/crescimento & desenvolvimento , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Bioacumulação , Reprodução , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento
13.
Medicine (Baltimore) ; 103(29): e38905, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39029047

RESUMO

The assessment of patient satisfaction following cataract surgery is heavily reliant on the evaluation of visual quality, specifically after the placement of diffractive multifocal intraocular lenses (MIOLs) under varying pupil conditions. The objective of this study was to examine the visual and optical clarity following cataract phacoemulsification and the use of Tecnis ZMB00 MIOL for implantation. The study involved 116 individuals (135 eyes) who received cataract phacoemulsification and underwent Tecnis ZMB00 MIOL implantation. Assessments were conducted 1 week and 3 months after the surgery. These assessments involved measuring uncorrected and corrected visual acuity for distant, intermediate, and near vision. Additionally, scatter light values and wavefront aberrations were measured under different aperture settings of 3 and 5 mm. There was no noticeable disparity in visual acuity between 1 week and 3 months after the surgery. After 3 months of surgery, there was a considerable decrease in scatter light values and spherical aberrations compared to the values observed 1 week after surgery, under the setting of a 5 mm aperture. Moreover, the modulation transfer function values showed a significant rise after 3 months following the surgery, particularly under the 5 mm aperture condition. The most substantial increase was observed at the intermediate spatial frequency of 20 cycles per degree (cpd), in comparison to the values obtained 1 week after the operation. The combination of cataract phacoemulsification and Tecnis ZMB00 MIOL implantation yielded favorable visual acuity at various distances for patients. Furthermore, enhancements in the measurements of scattered light, higher-order aberrations, and modulation transfer function values were noted 3 months after the surgical procedure, specifically under the condition of a 5 mm pupil. These findings suggest an increase in visual clarity and night vision to a certain degree.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares Multifocais , Facoemulsificação , Acuidade Visual , Humanos , Facoemulsificação/métodos , Feminino , Masculino , Idoso , Implante de Lente Intraocular/métodos , Pessoa de Meia-Idade , Satisfação do Paciente , Idoso de 80 Anos ou mais
14.
Animals (Basel) ; 14(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38891750

RESUMO

Hatchery rearing significantly influences the phenotypic development of fish, with potential adverse effects for the post-release performance of hatchery-reared individuals in natural environments, especially when targeted for stock enhancement. To assess the suitability of releasing hatchery-reared fish, a comprehensive understanding of the phenotypic effects of captive rearing, through comparisons with their wild conspecifics, is essential. In this study, we investigated the divergence in body coloration between wild and hatchery-reared marbled rockfish Sebastiscus marmoratus. We examined the selection preferences for different light colors and assessed the impact of different ambient light colors on the morphological color-changing ability of juvenile marbled rockfish. Our findings revealed significant differences in body color between wild and hatchery-reared marbled rockfish. The hue and saturation values of wild marbled rockfish were significantly higher than those of their hatchery-reared counterparts, indicative of deeper and more vibrant body coloration in the wild population. Following a ten-day rearing period under various light color environments, the color of wild marbled rockfish remained relatively unchanged. In contrast, hatchery-reared marbled rockfish tended to change their color, albeit not reaching wild-like coloration. Light color preference tests demonstrated that wild juvenile marbled rockfish exhibited a preference for a red-light environment, while hatchery-reared individuals showed a similar but weaker response. Both wild and hatchery-reared marbled rockfish displayed notable negative phototaxis in the presence of yellow and blue ambient light. These results highlight the impact of hatchery rearing conditions on the body color and morphological color-changing ability, and provide insight into light color selection preferences of marbled rockfish. To mitigate the divergence in phenotypic development and produce more wild-like fish for stocking purposes, modifications to the hatchery environment, such as the regulation of ambient light color, should be considered.

15.
Phys Rev Lett ; 132(21): 216301, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856294

RESUMO

A mobility edge (ME), representing the critical energy that distinguishes between extended and localized states, is a key concept in understanding the transition between extended (metallic) and localized (insulating) states in disordered and quasiperiodic systems. Here we explore the impact of dissipation on a quasiperiodic system featuring MEs by calculating steady-state density matrix and analyzing quench dynamics with sudden introduction of dissipation. We demonstrate that dissipation can lead the system into specific states predominantly characterized by either extended or localized states, irrespective of the initial state. Our results establish the use of dissipation as a new avenue for inducing transitions between extended and localized states and for manipulating dynamic behaviors of particles.

16.
Nano Lett ; 24(26): 8162-8170, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38904300

RESUMO

Developing efficient and CO-tolerant platinum (Pt)-based anodic catalysts is challenging for a direct formic acid fuel cell (DFAFC). Herein, we report heterostructured Pt-lead-sulfur (PtPbS)-based nanomaterials with gradual phase regulation as efficient formic acid oxidation reaction (FAOR) catalysts. The optimized Pt-PbS nanobelts (Pt-PbS NBs/C) display the mass and specific activities of 5.90 A mgPt-1 and 21.4 mA cm-2, 2.2/1.2, 1.5/1.1, and 36.9/79.3 times greater than those of PtPb-PbS NBs/C, Pt-PbSO4 NBs/C, and commercial Pt/C, respectively. Simultaneously, it exhibits a higher membrane electrode assembly (MEA) power density (183.5 mW cm-2) than commercial Pt/C (40.3 mW cm-2). This MEA stably operates at 0.4 V for 25 h, demonstrating a competitive potential of device application. The distinctive heterostructure endows the Pt-PbS NBs/C with optimized dehydrogenation steps and resisting the CO poisoning, thus presenting the remarkable FAOR performance. This work paves an effective avenue for creating high-performance anodic catalysts for fuel cells and beyond.

17.
J Chem Phys ; 160(21)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38832737

RESUMO

High voltage power capacitors employ the oil-impregnated polypropylene film as the insulation. The swelling phenomenon might drive the antioxidants and small molecules within the film to migrate into the oil. It is necessary to comprehensively investigate the physical migration mechanism of antioxidants and their impact on the electrical performance of the oil-film combination insulation system and, consequently, formulate the proper selective prescription of antioxidants. Theoretical elucidation of the competitive interaction mechanism between the film and the oil in attracting antioxidant molecules was achieved through the calculation of inter-molecular binding energy, and the migration coefficient ηm was introduced to quantify the migration characteristics of antioxidants. Experimentally, the effects of antioxidants on the space charge distribution of the film, the dielectric properties of the oil, and the breakdown characteristics of both the film and oil were investigated. The experimental conclusions are consistent with theoretical analysis. The lamellar structure antioxidant molecules with ηm > 1 tend to migrate from the film to the oil, which results in increased dielectric loss and decreased breakdown strength of the insulating oil. In addition, the presence of phosphorus atoms in phosphite antioxidants contributes to a reduction in the breakdown strength of the film. For capacitor grade polypropylene film, in addition to the synergistic effect between different types of antioxidants on the thermo-oxidative stability, the structure of the antioxidant molecules and its influence on the electrical performance of the oil-film systems should also be taken into account.

18.
JMIR Res Protoc ; 13: e53966, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888958

RESUMO

BACKGROUND: Depression poses a major threat to public health with an increasing prevalence in the United States. Mindfulness-based interventions, such as mindfulness-based cognitive therapy (MBCT), are effective methods for managing depression symptoms and may help fortify existing efforts to address the current disease burden. The in-person group format of MBCT, however, incurs barriers to care such as expenses, childcare needs, and transportation issues. Alternate delivery modalities such as MBCT delivered via the web can be investigated for their capacity to overcome these barriers and still reduce symptoms of depression with adequate feasibility and efficacy. OBJECTIVE: This study protocol aims to examine the feasibility and efficacy of MBCT delivered via the web for the treatment of depression. METHODS: To attain study aims, 2 phases will be implemented using a waitlist control design. A total of 128 eligible participants will be randomized into either an 8-week MBCT intervention group plus treatment as usual (MBCT + TAU; group 1) or an 8-week waitlist control group (group 2). In phase I (8 weeks), group 1 will complete the intervention and group 2 will proceed with TAU. In phase II (8 weeks), group 2 will complete the intervention and group 1 will continue with TAU until reaching an 8-week follow-up. TAU may consist of receiving psychotherapy, pharmacotherapy, or combined treatment. Data collection will be completed at baseline, 8 weeks (postintervention for group 1 and preintervention for group 2), and 16 weeks (follow-up for group 1, postintervention for group 2). The primary outcomes will include (1) current, residual, or chronic depression symptoms and (2) psychiatric distress. Secondary outcomes will include perceived stress and facets of mindfulness. The feasibility will be measured by assessing protocol adherence, retention, attendance, and engagement. Finally, the extent of mindfulness self-practice and executive functioning skills will be assessed as mediators of intervention outcomes. RESULTS: This study began screening and recruitment in December 2022. Data collection from the first cohort occurred in January 2023. By November 2023, a total of 30 participants were enrolled out of 224 who received screening. Data analysis began in February 2024, with an approximate publication of results by August 2024. Institutional review board approval took place on September 11, 2019. CONCLUSIONS: This trial will contribute to examining mindfulness-based interventions, delivered via the web, for improving current, residual, or chronic depression symptoms. It will (1) address the feasibility of MBCT delivered via the web; (2) contribute evidence regarding MBCT's efficacy in reducing depression symptoms and psychiatric distress; and (3) assess the impact of MBCT on several important secondary outcomes. Findings from this study will develop the understanding of the causal pathways between MBCT delivered via the web and depression symptoms further, elucidating the potential for future larger-scale designs. TRIAL REGISTRATION: ClinicalTrials.gov NCT05347719; https://www.clinicaltrials.gov/ct2/show/NCT05347719. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53966.


Assuntos
Terapia Cognitivo-Comportamental , Depressão , Atenção Plena , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Cognitivo-Comportamental/métodos , Depressão/terapia , Internet , Intervenção Baseada em Internet , Atenção Plena/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Insects ; 15(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38921114

RESUMO

Bemisia tabaci (Gennadius) is one of the most important invasive species in China, with strong insecticide resistance and thermotolerance. In this study, we investigated the effects of elevated temperature on the tolerance of B. tabaci MEMA1 to abamectin (AB) and thianethixam (TH) insecticides. We firstly cloned two new CYP450 genes from B. tabaci MEAM1, including one CYP6 family gene (BtCYP6k1) and one CYP305 family gene (BtCYP305a1). The expression patterns of the two BtCYP450 genes were compared in response to high-temperature stress and insecticide exposure, and RNAi was then used to demonstrate the role that these two genes play in insecticide tolerance. The results showed that expression of the two BtCYP450 genes could be induced by exposure to elevated temperature or insecticide, but this gene expression could be inhibited to a certain extent when insects were exposed to the combined effects of high temperature and insecticide treatment. For AB treatment, the expression of the two BtCYP450 genes reached the lowest level when insects were exposed to a temperature of 41 °C and treated with AB (combined effects of temperature and insecticide). In contrast, TH treatment showed a general decrease in the expression of the two BtCYP450 genes with exposure to elevated temperatures. These findings suggest that insecticide tolerance in B. tabaci MEAM1 could be mediated by high temperatures. This study provides a prospective method for the more effective application of insecticides for the control of B. tabaci in the field.

20.
Insects ; 15(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921175

RESUMO

Liriomyza trifolii is a significant invasive pest that targets horticultural and vegetable crops, causing large-scale outbreaks characterized by pronounced thermotolerance and insecticide resistance. This study examined the impact of long-term selection for abamectin resistance during the larval stage of L. trifolii on its population dynamics and thermal tolerance. We conducted a comprehensive comparison between the abamectin-resistant strain (AB-R) and the susceptible strain (S), including age-stage, two-sex life table analysis, thermal preference (Tpref), critical thermal maximum (CTmax), heat knockdown times (HKDTs), eclosion and survival rates, and LtHsp expression under heat stress. Our results showed that while selection for abamectin resistance was detrimental to survival and reproduction, it activated self-defense mechanisms and rapid adaptive adjustments and conferred modest thermal tolerance, which suggests a dual nature of insecticide effects. The AB-R strain exhibited significantly higher thermal preference and CTmax values, along with a longer HKDT and improved survival. Additionally, there was a significant upregulation of LtHsp expression in the AB-R strain compared to the S strain. These findings indicate that the evolution of thermal adaptation was accompanied by abamectin resistance development, emphasizing the necessity of considering temperature effects when applying chemical control. Our study provides valuable insights into how physiological acclimation may help mitigate the toxic effects of insecticides and illustrate how insects respond to multiple environmental pressures.

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