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1.
Phys Rev Lett ; 132(17): 176201, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728717

RESUMO

Nanoprotrusion (NP) on metal surface and its inevitable contamination layer under high electric field is often considered as the primary precursor that leads to vacuum breakdown, which plays an extremely detrimental effect for high energy physics equipment and many other devices. Yet, the NP growth has never been experimentally observed. Here, we conduct field emission (FE) measurements along with in situ transmission electron microscopy (TEM) imaging of an amorphous-carbon (a-C) coated tungsten nanotip at various nanoscale vacuum gap distances. We find that under certain conditions, the FE current-voltage (I-V) curves switch abruptly into an enhanced-current state, implying the growth of an NP. We then run field emission simulations, demonstrating that the temporary enhanced-current I-V is perfectly consistent with the hypothesis that a NP has grown at the apex of the tip. This hypothesis is also confirmed by the repeatable in situ observation of such a nanoprotrusion and its continued growth during successive FE measurements in TEM. We tentatively attribute this phenomenon to field-induced biased diffusion of surface a-C atoms, after performing a finite element analysis that excludes the alternative possibility of field-induced plastic deformation.

2.
IEEE Trans Med Imaging ; PP2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781069

RESUMO

Open-sided magnetic particle imaging (OS-MPI) has garnered significant interest due to its potential for interventional applications. However, the system matrix calibration in OS-MPI using sequential scans is a time-consuming task and susceptible to the low signal-to-noise ratio (SNR) resulting from the small calibration sample size. These challenges have hindered the practical implementation of system matrix-based reconstruction for sequentially scanned OS-MPI. To address these issues, we propose a novel calibration method, named sequential scan-based single-dimension multi-voxel calibration (SS-SDMVC), to efficiently obtain a high-SNR system matrix. This method was implemented in a cylindrical field of view (FOV), where a bar calibration sample parallel to the field-free line (FFL) was shifted along a fixed radial direction. A standard image reconstruction process was also introduced to verify the feasibility of SS-SDMVC. Through simulations, we analyzed the effects of noise levels and scanner imperfections on the SS-SDMVC-based reconstruction and demonstrated its robustness. In experiments, we compared the imaging performance of SS-SDMVC and the sequential scan-based traditional cubic-FOV SMC. The results showed that SS-SDMVC reduced the number of measurements by a factor of 210.94 and achieved higher reconstruction quality. Therefore, SS-SDMVC is expected to improve the reconstruction quality of human-scale or high-gradient FFL MPI scanners.

3.
Phys Med Biol ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38815602

RESUMO

OBJECTIVE: Magnetic particle imaging (MPI) is a promising imaging modality that leverages the nonlinear magnetization behavior of superparamagnetic iron oxide nanoparticles to determine their concentration distribution. Previous optimization models with multiple regularization terms have been proposed to achieve high-quality MPI reconstruction, but these models often result in increased computational burden, particularly for dense gridding 3D fields of view. In order to achieve faster reconstruction speeds without compromising reconstruction quality, we have developed a novel fused LASSO operator, total sum-difference (TSD), which effectively captures the sparse and smooth priors of MPI images. METHODS: Through an analysissynthesis equivalence strategy and a constraint smoothing strategy, the TSD regularized model was solved using the fast iterative soft-thresholding algorithm (FISTA). The resulting reconstruction method, TSD-FISTA, boasts low computational complexity and quadratic convergence rate over iterations. RESULTS: Experimental results demonstrated that TSD-FISTA required only 10% and 37% of the time to achieve comparable or superior reconstruction quality compared to commonly used fused LASSO-based ADMM and Tikhonov-based algebraic reconstruction techniques, respectively. SIGNIFICANCE: TSD-FISTA shows promise for enabling real-time 3D MPI reconstruction at high frame rates for large fields of view.

4.
Science ; 384(6693): 312-317, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38669572

RESUMO

Electrostatic capacitors are foundational components of advanced electronics and high-power electrical systems owing to their ultrafast charging-discharging capability. Ferroelectric materials offer high maximum polarization, but high remnant polarization has hindered their effective deployment in energy storage applications. Previous methodologies have encountered problems because of the deteriorated crystallinity of the ferroelectric materials. We introduce an approach to control the relaxation time using two-dimensional (2D) materials while minimizing energy loss by using 2D/3D/2D heterostructures and preserving the crystallinity of ferroelectric 3D materials. Using this approach, we were able to achieve an energy density of 191.7 joules per cubic centimeter with an efficiency greater than 90%. This precise control over relaxation time holds promise for a wide array of applications and has the potential to accelerate the development of highly efficient energy storage systems.

5.
J Ethnopharmacol ; 327: 118049, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38484954

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Liriope spicata Lour., a species listed in the catalogue of 'Medicinal and Edible Homologous Species', is traditionally used for the treatment of fatigue, restlessness, insomnia and constipation. AIM OF THE STUDY: This study is aimed to evaluate the sedative and hypnotic effect of the saponins from a natural plant L. spicata Lour. in vivo. MATERIALS AND METHODS: The total saponin (LSTS) and purified saponin (LSPS) were extracted from L. spicata, followed by a thorough analysis of their major components using the HPLC-MS. Subsequently, the therapeutic efficacy of LSTS and LSPS was evaluated by the improvement of anxiety and depression behaviors of the PCPA-induced mice. RESULTS: LSTS and LSPS exhibited similar saponin compositions but differ in their composition ratios, with liriopesides-type saponins accounting for a larger proportion in LSTS. Studies demonstrated that both LSTS and LSPS can extend sleep duration and immobility time, while reducing sleep latency in PCPA-induced mice. However, there was no significant difference in weight change among the various mice groups. Elisa results indicated that the LSTS and LSPS could decrease levels of NE, DA, IL-6, and elevate the levels of 5-HT, NO, PGD2 and TNF-α in mice plasma. LSTS enhanced the expression of neurotransmitter receptors, while LSPS exhibited a more pronounced effect in regulating the expression of inflammatory factors. In conclusion, the saponins derived from L. spicata might hold promise as ingredients for developing health foods with sedative and hypnotic effects, potentially related to the modulation of serotonergic and GABAAergic neuron expression, as well as immunomodulatory process.


Assuntos
Saponinas , Distúrbios do Início e da Manutenção do Sono , Animais , Camundongos , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Saponinas/farmacologia , Saponinas/uso terapêutico , Plantas Comestíveis , Ansiedade
6.
Psychol Res Behav Manag ; 17: 905-915, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464810

RESUMO

Purpose: Mainland universities have become one of the important choices for students from Hong Kong, Macao and Taiwan, but the maladaptation caused by environmental migration will have a negative impact on the mental health of them. Therefore, it is urgent to explore the psychological mechanism of sociocultural adaptation of Hong Kong, Macao and Taiwan students. Methods: In order to explore the influence of self-esteem on the sociocultural adaptation of college students of Hong Kong, Macao and Taiwan studying in mainland universities, as well as the mechanism of social support and school belonging, a survey was conducted among 1108 college students from Hong Kong, Macao and Taiwan studying in mainland universities, with the help of Rosenberg Self-Esteem Scale, Sociocultural Adaptation Scale, Perceptive Social Support Scale and The Psychological Sense of School belonging Scale. Results: The results show that (1) Different grades of college students of Hong Kong, Macao and Taiwan have differences in school belonging and sociocultural adaptation (P<0.05); (2) Self-esteem, social support, school belonging and sociocultural adaptation were positively correlated (P < 0.01); (3) The mediation model test showed that self-esteem could directly and positively predict sociocultural adaptation with a direct effect size of 0.245; Social support and school belonging played a mediating role between self-esteem and sociocultural adaptation, and the mediating effect sizes were 0.094 and 0.085, respectively. The chain mediating effect of social support and school belonging was also significant, and the mediating effect size was 0.108. Conclusion: Self-esteem can not only directly affect college students' sociocultural adaptation, but also indirectly affect college students' sociocultural adaptation through the chain mediating effect of social support and school belonging. This study further reveals the mechanism of self-esteem on sociocultural adaptation and provides psychological basis for universities to improve the sociocultural adaptation level of different groups of students.

7.
Int J Food Microbiol ; 413: 110611, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308880

RESUMO

In the present study, the synergistic bactericidal effect and mechanism of ultrasound (US) combined with Lauroyl Arginate Ethyl (LAE) against Salmonella Typhimurium were investigated. On this basis, the effect of US+LAE treatment on the washing of S. Typhimurium on the surface of onions and on the physical and chemical properties of onion during fresh-cutting and storage were studied. The results showed that treatment with US+LAE could significantly (P < 0.05) reduce the number of S. Typhimurium compared to US and LAE treatments alone, especially the treatment of US+LAE (230 W/cm2, 8 min, 71 µM) reduced S. Typhimurium by 8.82 log CFU/mL. Confocal laser scanning microscopy (CLSM), flow cytometry (FCM), protein and nucleic acid release and N-phenyl-l-naphthylamine (NPN) assays demonstrated that US+LAE disrupted the integrity and permeability of S. Typhimurium cell membranes. Reactive oxygen species (ROS) and malondialdehyde (MDA) assays indicated that US+LAE exacerbated oxidative stress and lipid peroxidation in cell membranes. Field emission scanning electron microscopy (FESEM) demonstrated that US+LAE treatment caused loss of cellular contents and led to cell crumpling and even lost the original cell morphology. US+LAE treatment caused a significant (P < 0.05) decrease in the number of S. Typhimurium on onions, but there was no significant (P > 0.05) effect on the color, hardness, weight and ascorbic acid content of onions. This study elucidated the synergistic antibacterial mechanism of US+LAE and verified the feasibility of bactericidal effect on the surface of onions, providing a theoretical basis for improving the safety of fresh produce in the food industry and to propose a new way to achieve the desired results.


Assuntos
Cebolas , Salmonella typhimurium , Antibacterianos/farmacologia , Preservação Biológica , Microscopia Eletrônica de Varredura , Arginina/farmacologia
8.
Adv Mater ; : e2400138, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38402444

RESUMO

Kesterites, Cu2ZnSn(SxSe1- x)4 (CZTSSe), solar cells suffer from severe open-circuit voltage (VOC) loss due to the numerous secondary phases and defects. The prevailing notion attributes this issue to Sn-loss during the selenization. However, this work unveils that, instead of Sn-loss, elemental inhomogeneity caused by Cu-directional diffusion toward Mo(S,Se)2 layer is the critical factor in the formation of secondary phases and defects. This diffusion decreases the Cu/(Zn+Sn) ratio to 53% at the bottom fine-grain layer, increasing the Sn-/Zn-related bulk defects. By suppressing the Cu-directional diffusion with a blocking layer, the crystal quality is effectively improved and the defect density is reduced, leading to a remarkable photovoltaic coversion efficiency (PCE) of 14.9% with a VOC of 576 mV and a certified efficiency of 14.6%. The findings provide insights into element inhomogeneity, holding significant potential to advance the development of CZTSSe solar cells.

9.
Reprod Biol Endocrinol ; 22(1): 24, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373962

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders in females of childbearing age. Various types of ovarian cells work together to maintain normal reproductive function, whose discordance often takes part in the development and progression of PCOS. Understanding the cellular heterogeneity and compositions of ovarian cells would provide insight into PCOS pathogenesis, but are, however, not well understood. Transcriptomic characterization of cells isolated from PCOS cases have been assessed using bulk RNA-seq but cells isolated contain a mixture of many ovarian cell types. METHODS: Here we utilized the reference scRNA-seq data from human adult ovaries to deconvolute and estimate cell proportions and dysfunction of ovarian cells in PCOS, by integrating various granulosa cells(GCs) transcriptomic data. RESULTS: We successfully defined 22 distinct cell clusters of human ovarian cells. Then after transcriptome integration, we obtained a gene expression matrix with 13,904 genes within 30 samples (15 control vs. 15 PCOS). Subsequent deconvolution analysis revealed decreased proportion of small antral GCs and increased proportion of KRT8high mural GCs, HTRA1high cumulus cells in PCOS, especially increased differentiation from small antral GCs to KRT8high mural GCs. For theca cells, the abundance of internal theca cells (TCs) and external TCs was both increased. Less TCF21high stroma cells (SCs) and more STARhigh SCs were observed. The proportions of NK cells and monocytes were decreased, and T cells occupied more in PCOS and communicated stronger with inTCs and exTCs. In the end, we predicted the candidate drugs which could be used to correct the proportion of ovarian cells in patients with PCOS. CONCLUSIONS: Taken together, this study provides insights into the molecular alterations and cellular compositions in PCOS ovarian tissue. The findings might contribute to our understanding of PCOS pathophysiology and offer resource for PCOS basic research.


Assuntos
Síndrome do Ovário Policístico , Adulto , Feminino , Humanos , Síndrome do Ovário Policístico/metabolismo , Transcriptoma , Células da Granulosa/metabolismo , Perfilação da Expressão Gênica , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
10.
Sci Rep ; 14(1): 5019, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424234

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine metabolic disorders. The lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) reportedly can regulate the reproductive system. Despite studies, the alteration of MALAT1 expression in granulosa cells (GCs) from PCOS patients was inconsistent. To evaluate MALAT1 expression in GCs in different PCOS subgroups and its association with PCOS phenotypes, we collected GCs from 110 PCOS cases and 71 controls, and examined MALAT1 expression by quantitative PCR. The results showed MALAT1 expression was upregulated in PCOS cases, especially in insulin resistant (IR) PCOS subgroup, obese PCOS subgroup and non-hyperandrogenic (NHA) PCOS subgroup. MALAT1 expression was positively correlated with BMI and several metabolic parameters in controls. Interestingly, MALAT1 expression was notably associated with some critical endocrine indexes for PCOS, including E2, FSH, LH and LH/FSH ratio. In different PCOS subgroups, we found significant positive correlations with LH/FSH ratio in IR-PCOS and PCOS with normal weight, and with serum T and LH level in NHA-PCOS subgroup. Integrated analysis with lncRNA target databases and PCOS-related databases revealed MALAT1 could participate in PCOS by influencing immune response and lipids metabolism in GCs. In conclusion, MALAT1 was differently expressed in GCs in PCOS, especially in IR, obese and NHA PCOS subgroups. MALAT1 was likely involved in metabolism and immune response in GCs in PCOS. However, more studies are necessary to establish this concept.


Assuntos
Síndrome do Ovário Policístico , RNA Longo não Codificante , Feminino , Humanos , Hormônio Foliculoestimulante , Células da Granulosa/metabolismo , Insulina/metabolismo , Obesidade/complicações , Obesidade/genética , Obesidade/metabolismo , Fenótipo , Síndrome do Ovário Policístico/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
Transl Lung Cancer Res ; 13(1): 152-162, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38405000

RESUMO

Background: Alectinib, a next-generation anaplastic lymphoma kinase tyrosine kinase inhibitor (ALK-TKI), has demonstrated noteworthy efficacy in the treatment of non-small cell lung cancer (NSCLC). Unfortunately, 53.3% of untreated patients receiving first-line treatment with alectinib developed resistance to alectinib. However, despite the widespread use of alectinib, studies on the efficacy and safety of continuing alectinib with other necessary therapies after progression of alectinib and possible population of benefit are still limited. Methods: This retrospective cohort study included fifteen patients with ALK-positive NSCLC from nine institutions in China who experienced disease progression after first- or second-line treatment and continued to receive alectinib treatment between 2019 and 2022. This study aimed to evaluate the median progression-free survival (mPFS), objective response rate (ORR), median overall survival (mOS), and adverse events (AEs) of continuing alectinib combined with other therapies after the emergence of drug resistance. Results: Among fifteen patients eligible for this study, all patients started continuing treatment with alectinib after oligoprogression or central nervous system (CNS) progression. The mPFS for the whole cohort receiving continuing alectinib with other necessary therapies was 8 months [95% confidence interval (CI): 4 to not applicable (NA)], with an ORR of 46.7%. The mOS was not reached. During continuing alectinib treatment, only one patient experienced grade 2 elevation of aspartate aminotransferase (AST) and serum glutamic-oxaloacetic transaminase (SGOT). Conclusions: The continuation of alectinib treatment combined with other necessary therapies demonstrates favorable response and safety in patients with ALK-positive NSCLC who experienced oligoprogression or CNS progression following alectinib in first- or second-line therapy. Instead of immediately switching to another ALK-TKI, continuing alectinib combined with other necessary therapies may offer greater survival benefits to the patients.

12.
Heliyon ; 10(1): e23750, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192850

RESUMO

Cisplatin (CDDP) stands as a highly effective chemotherapeutic agent; however, its ototoxicity remains a perplexing challenge in the field. Formononetin (FMNT), a potent flavonoid isolated from Astragalus membranaceus, displays a diverse range of promising pharmacological activities, encompassing antioxidant, anti-apoptotic, and anti-inflammatory effects. Nonetheless, the advantageous effects of FMNT on cisplatin-induced cochlear hair cell injury demand further investigation. This study aimed to assess the protective properties of FMNT against cisplatin-induced hair cell damage by conducting in vitro assays on explant-cultured cochlear hair cells. The findings revealed that FMNT exhibited a notable reduction in cisplatin-induced hair cell apoptosis. Also, FMNT effectively mitigated the accumulation of reactive oxygen species and mitochondrial damage in cochlear explants exposed to cisplatin, while also restoring the turnover of the reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio. Furthermore, our study demonstrated that FMNT protects hair cells against CDDP injury through the activation of the PI3K/AKT-Nrf2 signaling pathway. Consequently, formononetin emerges as a potential therapeutic agent for the treatment of cisplatin-induced ototoxicity.

13.
Ultrason Sonochem ; 102: 106752, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38211495

RESUMO

This study investigated the antibacterial effects of ultrasound (US), ß-citronellol (CT), and a combination of the two treatments on Listeria monocytogenes. Results showed that US or CT alone did not show apparent antibacterial effect (0.02-0.76 log CFU/mL reduction). The combined treatment showed obviously inactivate effect of L. monocytogenes, the populations of L. monocytogenes decreased by 8.93 log CFU/mL after US (253 W/cm2, 20 kHz) + 0.8 mg/mL CT treatment. US + CT treatment also had a significant (P < 0.05) antibacterial effect on isolates of L. monocytogenes from three different serotypes. In this study, the damage of US + CT on cell morphology had been observed using field emission scanning electron microscopy, while the damage to cell membranes by US + CT was observed by confocal laser scanning microscopy and flow cytometry. Meanwhile, the uptake of N-phenyl-l-naphthylamine and the absorbance at 260 and 280 nm also indicated that the combined treatment disrupted the permeability and integrity of L. monocytogenes membranes. Reactive oxygen species and malondialdehyde assays showed that US + CT exacerbated cellular oxidative stress and lipid peroxidation. In addition, the US + CT treatment reduced L. monocytogenes by 3.14-4.24 log CFU/g on the surface of carrots. Total phenolic and carotenoid contents in carrots were elevated after US + CT treatment. During storage, compared to control, US + CT did not significantly (P > 0.05) change the surface color of carrots but significantly (P < 0.05) decreased both hardness and weight, and has an impact on the sensory. This study showed that US + CT is a promising cleaning method that will provide new ideas for the preservation of fresh agricultural produce.


Assuntos
Monoterpenos Acíclicos , Daucus carota , Listeria monocytogenes , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Antibacterianos/farmacologia , Conservação de Alimentos/métodos
14.
Heliyon ; 10(1): e23980, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38226268

RESUMO

This study presents a Modified version of Chaos Grasshopper Algorithm (MCGA) as a solution to the Techno-Economic Energy Management Strategy (TEMS) problem in microgrids. Our main contribution is the optimization of parameters to minimize the overall daily electricity price in an integrated clean energy micro-grid, incorporating fuel cell, battery storage, and photovoltaic systems. Through comparative simulations with established methods (HOMER, GAMS, GWO, and MILPA), we demonstrate the superiority of our proposed strategy. The results reveal that MCGA surpasses these methods, yielding significantly improved optimal solutions for the overall daily electricity price. Notably, the MCGA approach exhibits high precision, flexibility, and adaptability to power prices and environmental constraints, leading to accurate and flexible solutions. Thus, our proposed approach offers a promising and effective solution for the TEMS problem in microgrids, with the potential to greatly enhance microgrid performance.

15.
CNS Neurosci Ther ; 30(2): e14403, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37577804

RESUMO

AIM: Cinchonine (CN) and its isomer cinchonidine (CD), two of the common cinchona alkaloids, are wildly used as antimalarial drugs. However, the effects of CN and CD on the auditory system are unknown. METHODS: Molecular docking and molecular dynamics (MD) simulation were used for predicting effective drugs. The CCK-8 assay was conducted for assessing cell viability in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells. MitoSox Red staining revealed reactive oxygen species (ROS) amounts. TMRM staining was used to assess the mitochondrial membrane potential (ΔΨm). Immunofluorescence staining of myosin 7a was used to examine hair cells (HCs) in cisplatin-treated neonatal mouse cochlear explants, while TUJ-1 immunostaining was used for the detection of spiral ganglion neurons (SGNs). Cleaved caspase-3 and TUNEL immunostaining were utilized for apoptosis assessment. Immunoblot was carried out to detect PI3K-AKT signaling effectors. RESULTS: Pretreatment with CN or CD significantly increased cell viability and reduced mitochondrial dysfunction and ROS accumulation in cisplatin-treated HEI-OC1 cells. Immunofluorescent staining of cochlear explants showed that CN and CD attenuated cisplatin-induced damage to SGNs and HCs. Immunoblot revealed that CN and CD downregulated the expression of cleaved caspase-3 and activated PI3K-AKT signaling in cisplatin-injured HEI-OC1 cells. CONCLUSION: CD and CN can reduce ototoxicity caused by cisplatin and might help treat cisplatin-associated hearing loss.


Assuntos
Antineoplásicos , Alcaloides de Cinchona , Ototoxicidade , Camundongos , Animais , Cisplatino/toxicidade , Antineoplásicos/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Caspase 3/metabolismo , Fosfatidilinositol 3-Quinases , Espécies Reativas de Oxigênio/metabolismo , Ototoxicidade/tratamento farmacológico , Simulação de Acoplamento Molecular , Alcaloides de Cinchona/farmacologia , Apoptose
16.
Adv Sci (Weinh) ; 11(6): e2306833, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38044320

RESUMO

Solar-driven interfacial evaporation (SDIE) has attracted great attention by offering a zero-carbon-emission solution for clean water production. The manipulation of the surface structure of the evaporator markedly promotes the enhancement of light capture and the improvement of evaporation performance. Herein, inspired by seedless lotus pod, a flexible pristine polypyrrole (PPy) membrane with macro/micro-bubble and nanotube asymmetric structure is fabricated through template-assisted interfacial polymerization. The macro- and micro-hierarchical structure of the open bubbles enable multiple reflections inner and among the bubble cavities for enhanced light trapping and omnidirectional photothermal conversion. In addition, the multilevel structure (macro/micro/nano) of the asymmetric PPy (PPy-A) membrane induces water evaporation in the form of clusters, leading to a reduction of water evaporation enthalpy. The PPy-A membranes achieve a full-spectrum light absorption of 96.3% and high evaporation rate of 2.03 kg m-2  h-1 under 1 sun. Long-term stable desalination is also verified with PPy-A membranes by applying one-way water channel. This study demonstrates the feasibility of pristine PPy membranes in SDIE applications, providing guidelines for modulation of the evaporator topologies toward high-efficient solar evaporation.

17.
Small ; 20(19): e2308266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100155

RESUMO

Developing well-crystallized light-absorbing layers remains a formidable challenge in the progression of kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. A critical aspect of optimizing CZTSSe lies in accurately governing the high-temperature selenization reaction. This process is intricate and demanding, with underlying mechanisms requiring further comprehension. This study introduces a precursor microstructure-guided hetero-nucleation regulation strategy for high-quality CZTSSe absorbers and well-performing solar cells. The alcoholysis of 2-methoxyethanol (MOE) and the generation of high gas-producing micelles by adding hydrogen chloride (HCl) as a proton additive into the precursor solution are successfully suppressed. This tailored modification of solution components reduces the emission of volatiles during baking, yielding a compact and dense precursor microstructure. The reduced-roughness surface nurtures the formation of larger CZTSSe nuclei, accelerating the ensuing Ostwald ripening process. Ultimately, CZTSSe absorbers with enhanced crystallinity and diminished defects are fabricated, attaining an impressive 14.01% active-area power conversion efficiency. The findings elucidate the influence of precursor microstructure on the selenization reaction process, paving a route for fabricating high-quality kesterite CZTSSe films and high-efficiency solar cells.

18.
Stroke ; 55(1): 113-121, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134266

RESUMO

BACKGROUND: The extent to which genetic susceptibility modifies the associations between air pollutants and the risk of incident stroke is still unclear. This study was designed to investigate the separate and joint associations of long-term exposure to air pollutants and genetic susceptibility on stroke risk. METHODS: The participants of this study were recruited by the UK Biobank between 2006 and 2010. These participants were followed up from the enrollment until the occurrence of stroke events or censoring of data. Hazard ratios (HRs) and 95% CIs for stroke events associated with long-term exposure to air pollutants were estimated by fitting both crude and adjusted Cox proportional hazards models. Additionally, the polygenic risk score was calculated to estimate whether the polygenic risk score modifies the associations between exposure to air pollutants and incident stroke. RESULTS: A total of 502 480 subjects were included in this study. After exclusion, 452 196 participants were taken into the final analysis. During a median follow-up time of 11.7 years, 11 334 stroke events were observed, with a mean age of 61.60 years, and men accounted for 56.2% of the total cases. Long-term exposures to particulate matter with an aerodynamic diameter smaller than 2.5 µm (adjusted HR, 1.70 [95% CI, 1.43-2.03]) or particulate matter with an aerodynamic diameter smaller than 10 µm (adjusted HR, 1.50 [95% CI, 1.36-1.66]), nitrogen dioxide (adjusted HR, 1.10 [95% CI, 1.07-1.12]), and nitrogen oxide (adjusted HR, 1.04 [95% CI, 1.02-1.05]) were pronouncedly associated with increased risk of stroke. Meanwhile, participants with high genetic risk and exposure to high air pollutants had ≈45% (31%, 61%; particulate matter with an aerodynamic diameter smaller than 2.5 µm), 48% (33%, 65%; particulate matter with an aerodynamic diameter smaller than 10 µm), 51% (35%, 69%; nitrogen dioxide), and 39% (25%, 55%; nitrogen oxide) higher risk of stroke compared with those with low genetic risk and exposure to low air pollutants, respectively. Of note, we observed additive and multiplicative interactions between genetic susceptibility and air pollutants on stroke events. CONCLUSIONS: Chronic exposure to air pollutants was associated with an increased risk of stroke, especially in populations at high genetic risk.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Estudos de Coortes , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Dióxido de Nitrogênio/efeitos adversos , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , Material Particulado/análise , Óxidos de Nitrogênio , Predisposição Genética para Doença , Óxido Nítrico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/induzido quimicamente
19.
Artigo em Inglês | MEDLINE | ID: mdl-38083253

RESUMO

Magnetic particle imaging (MPI) is a medical imaging technology with high resolution and high sensitivity, which tracks the distribution of superparamagnetic iron oxide nanoparticles (SPIONs) in the nonlinear response to dynamic excitation at a field-free region. However, various noises distort the signals resulting in a decline in imaging quality. Traditional threshold-based methods cannot remove dynamic noise in MPI signals. Therefore, a self-supervised denoising method is proposed to denoise MPI signals in this study. The approach adopted U-net as the backbone and modified the network for MPI signals. The network is trained using two periods of noisy signals and the shape prior knowledge of the MPI signals is introduced for promoting the convergence of the self-supervised net. The experiments show that the learning-based method can still denoising the MPI signal without labeling data and eventually improve image quality, and our approach can achieve the best performance compared with other self-supervised methods in MPI signal denoising.


Assuntos
Diagnóstico por Imagem , Nanopartículas de Magnetita , Diagnóstico por Imagem/métodos , Fenômenos Magnéticos
20.
Front Immunol ; 14: 1282890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38053999

RESUMO

Changes in lifestyle induce an increase in patients with hyperuricemia (HUA), leading to gout, gouty arthritis, renal damage, and cardiovascular injury. There is a strong inflammatory response in the process of HUA, while dysregulation of immune cells, including monocytes, macrophages, and T cells, plays a crucial role in the inflammatory response. Recent studies have indicated that urate has a direct impact on immune cell populations, changes in cytokine expression, modifications in chemotaxis and differentiation, and the provocation of immune cells by intrinsic cells to cause the aforementioned conditions. Here we conducted a detailed review of the relationship among uric acid, immune response, and inflammatory status in hyperuricemia and its complications, providing new therapeutic targets and strategies.


Assuntos
Artrite Gotosa , Gota , Hiperuricemia , Humanos , Hiperuricemia/complicações , Hiperuricemia/metabolismo , Ácido Úrico/metabolismo , Gota/tratamento farmacológico , Artrite Gotosa/tratamento farmacológico , Inflamação/complicações
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