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1.
BMC Public Health ; 24(1): 1769, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961390

RESUMO

BACKGROUND: This study aimed to assess the public knowledge regarding Alzheimer's Disease (AD) in Zhuhai, China, focusing on identifying knowledge gaps and the influence of demographic and health factors. METHODS: A cross-sectional study was conducted in Zhuhai, China, from October to November 2022. A total of 1986 residents from 18 communities were selected employing stratified multi-stage equi-proportional sampling. Questionnaires covering general information and the Alzheimer's Disease Knowledge Scale (ADKS) were investigated face-to-face. Ordinal multiclass logistic regression was applied to assess the relationship between AD awareness and demographic and health characteristics. RESULTS: The average ADKS score was 18.5 (SD = 3.36) in Zhuhai. The lowest awareness rates were observed in the "Symptoms" and "Caregiving" subdomains of ADKS, with rates of 51.01% and 43.78%, respectively. The correct rates for the 30 ADKS questions ranged from 16.62 to 92.6%, showing a bimodal pattern with clusters around 80% and 20%. Women (OR = 1.203, 95% CI: 1.009-1.435), individuals aged 60 years or older (OR = 2.073, 95% CI: 1.467-2.932), those living in urban areas (OR = 1.361, 95% CI: 1.117-1.662), higher average monthly household income per capita (OR = 1.641, 95% CI: 1.297-2.082), and without any neurological or mental disorders (OR = 1.810, 95% CI: 1.323-2.478) were more likely to have higher levels of awareness about Alzheimer's disease. CONCLUSIONS: Adults in Zhuhai show a limited knowledge of AD, particularly in the 'Symptoms' and 'Caregiving' subdomains. Upcoming health campaigns must focus on bridging the knowledge gaps in different subdomains of AD, especially among subgroups with lower awareness, as identified in our study.


Assuntos
Doença de Alzheimer , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudos Transversais , China/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Inquéritos e Questionários , Adulto Jovem
2.
Nanomaterials (Basel) ; 14(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38921920

RESUMO

In the field of perovskite optoelectronics, developing hole-transporting materials (HTMs) on the spiro[fluorene-9,9'-xanthene] (SFX) platform is one of the current research focuses. The SFX inherits the merits of spirobifluorene in terms of the configuration and property, but it is more easily derivatized and regulated by virtue of its binary structure. In this work, we design and synthesize four isomeric SFX-based HTMs, namely m-SFX-mF, p-SFX-mF, m-SFX-oF, and p-SFX-oF, through varying the positions of fluorination on the peripheral aniline units and their substitutions on the SFX core, and the optoelectronic performance of the resulting HTMs is evaluated in both perovskite solar cells (PSCs) and light-emitting diodes (PeLEDs) by the vacuum thermal evaporating hole-transporting layers (HTLs). The HTM p-SFX-oF exhibits an improved power conversion efficiency of 15.21% in an inverted PSC using CH3NH3PbI3 as an absorber, benefiting from the deep HOMO level and good HTL/perovskite interface contact. Meanwhile, the HTM m-SFX-mF provides a maximum external quantum efficiency of 3.15% in CsPb(Br/Cl)3-based PeLEDs, which is attributed to its perched HOMO level and shrunken band-gap for facilitating charge carrier injection and then exciton combination. Through elucidating the synergistic position effect of fluorination on aniline units and their substitutions on the SFX core, this work lays the foundation for developing low-cost and efficient HTMs in the future.

3.
World J Otorhinolaryngol Head Neck Surg ; 10(2): 113-120, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855290

RESUMO

Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.

4.
Phys Chem Chem Phys ; 26(25): 17599-17608, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864183

RESUMO

We conducted a study on the trajectory-dependent threshold effects of proton stopping power in LiF nanosheets using time-dependent density functional theory non-adiabatically coupled to the molecular dynamics. This study covered protons with initial velocities in the range of 0.1-1.0 a.u., offering a vast amount of detailed information on the electronic structure during the stopping process with superior spatial and temporal resolution. Our results show that the impact parameters of incident protons play a crucial role in determining the threshold behavior of proton stopping power in LiF nanosheets. Most importantly, we found that close collisions do not exhibit a discernible threshold. In addition, the research results also revealed the time dependence of the number of electrons occupying the atomic orbitals of F and Li as protons pass through the nanosheets.

5.
Chemosphere ; 361: 142462, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38815816

RESUMO

As perfluorooctanoic acid (PFOA) alternatives, hexafluoropropylene oxide dimeric acid (HFPO-DA) and hexafluoropropylene oxide trimeric acid (HFPO-TA) have been increasingly used and caused considerable water pollution. However, their toxicities to aquatic organisms are still not well known. Therefore, in this study, zebrafish embryos were exposed to PFOA (0, 1.5, 3 and 6 mg/L), HFPO-DA (0, 3, 6 and 12 mg/L) and HFPO-TA (0, 1, 2 and 4 mg/L) to comparatively investigate their thyroid disrupting effects and the developmental toxicity. Results demonstrated that waterborne exposure to PFOA and its two alternatives decreased T4 contents, the heart rate and swirl-escape rate of zebrafish embryos/larvae. The transcription levels of genes related to thyroid hormone regulation (crh), biosynthesis (tpo and tg), function (trα and trß), transport (transthyretin, ttr), and metabolism (dio1, dio2 and ugt1ab), were differently altered after the exposures, which induced the thyroid disrupting effects and decreased the heart rate. In addition, the transcription levels of some genes related to the nervous system development were also significantly affected, which was associated with the thyroid disrupting effects and consequently affected the locomotor activity of zebrafish. Therefore, HFPO-DA and HFPO-TA could not be safe alternatives to PFOA. Further studies to uncover the underlying mechanisms of these adverse effects are warranted.


Assuntos
Embrião não Mamífero , Fluorocarbonos , Glândula Tireoide , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/embriologia , Fluorocarbonos/toxicidade , Glândula Tireoide/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Caprilatos/toxicidade , Disruptores Endócrinos/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Hormônios Tireóideos/metabolismo
6.
BMJ Open ; 14(5): e085645, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802272

RESUMO

OBJECTIVES: This study explored the association between the Frailty Index (FI) and low back pain (LBP) in middle-aged and older Chinese adults. We hypothesised that a higher FI correlates with increased LBP prevalence. DESIGN: Cross-sectional analysis. SETTING: The study used data from the China Health and Retirement Longitudinal Study (CHARLS) across various regions of China. PARTICIPANTS: The analysis included 6375 participants aged 45 and above with complete LBP and FI data from the CHARLS for 2011, 2013 and 2015. We excluded individuals under 45, those with incomplete LBP data, participants with fewer than 30 health deficit items and those missing covariate data. OUTCOME MEASURES: We constructed an FI consisting of 35 health deficits. Logistic multivariable regression examined the relationship between FI and LBP, using threshold analysis to identify inflection points. Sensitivity analyses were performed to ensure the robustness of the findings. RESULTS: Of the participants, 27.2% reported LBP. A U-shaped association was observed between FI and LBP, with the highest quartile (Q4, FI ≥0.23) showing more than a twofold increased risk of LBP (OR=2.90, 95% CI: 2.45-3.42, p<0.001). Stratified analysis showed a significant association in participants under 60, particularly in the lowest FI quartile (OR=1.43, 95% CI: 1.14 to 1.79). Sensitivity analysis upheld the robustness of the primary results. CONCLUSIONS: The findings suggest a complex relationship between frailty and LBP, highlighting the need for early screening and tailored interventions to manage LBP in this demographic. Further research is necessary to understand the mechanisms of this association and to validate the findings through longitudinal studies.


Assuntos
Fragilidade , Dor Lombar , Humanos , Dor Lombar/epidemiologia , Masculino , China/epidemiologia , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Idoso , Estudos Longitudinais , Fragilidade/epidemiologia , Fragilidade/diagnóstico , Prevalência , Modelos Logísticos , Fatores de Risco , Idoso de 80 Anos ou mais , População do Leste Asiático
7.
Phys Chem Chem Phys ; 26(22): 16253-16260, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804578

RESUMO

Dynamic infrared radiation regulation has been widely explored for smart windows because of its vital importance for comfortable and energy-efficient buildings. However, it remains a great challenge to synchronously achieve high visible transmittance and pronounced infrared tunability. Here, we propose a dynamic infrared tunable metamaterial composed of indium tin oxide (ITO) gratings, an air insulator, and an ITO reflector. The ITO grating-based infrared radiation regulator exhibits a high emissivity tunability of 0.73 at 8-13 µm while maintaining a high visible transmittance of 0.65 and 0.72 before and after actuation, respectively. By adjusting the geometric parameters, the tunable bandwidth can be further extended to 3-30 µm and the ultra-broadband tunability reaches 0.62. The excellent infrared tunable performance arises from the insulator thickness-dependent effect of Fabry-Pérot and propagating surface plasmon resonance coupling and decoupling, which lead to perfect and low absorption, respectively. This work provides potential for the advancement of smart window technology and makes a significant contribution to sustainable buildings.

8.
Bioresour Bioprocess ; 11(1): 17, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38647810

RESUMO

Cell immobilization plays an important role in biocatalysis for high-value products. It is necessary to maintain the viability of immobilized cells for bioconversion using viable cells as biocatalysts. In this study, a novel polyester nonwoven chemostat was designed for cell immobilization to investigate biofilm formation and the dynamic balance between adsorption and desorption of cells on polyester nonwoven. The polyester nonwoven was suitable for cell immobilization, and the cell numbers on the polyester nonwoven can reach 6.5 ± 0.38 log CFU/mL. After adding the polyester nonwoven to the chemostat, the fluctuation phenomenon of free bacterial cells occurred. The reason for this phenomenon was the balance between adsorption and desorption of bacterial cells on the polyester nonwoven. Bacterial cells could adhere to the surface of polyester nonwoven via secreting extracellular polymeric substances (EPS) to form biofilms. As the maturation of biofilms, some dead cells inside the biofilms can cause the detachment of biofilms. This process of continuous adsorption and desorption of cells can ensure that the polyester nonwoven chemostat has lasting biological activity.

9.
J Neuroinflammation ; 21(1): 99, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632655

RESUMO

BACKGROUND: The pathogenesis of memory impairment, a common complication of chronic neuropathic pain (CNP), has not been fully elucidated. Schwann cell (SC)-derived extracellular vesicles (EVs) contribute to remote organ injury. Here, we showed that SC-EVs may mediate pathological communication between SCs and hippocampal neurons in the context of CNP. METHODS: We used an adeno-associated virus harboring the SC-specific promoter Mpz and expressing the CD63-GFP gene to track SC-EVs transport. microRNA (miRNA) expression profiles of EVs and gain-of-function and loss-of-function regulatory experiments revealed that miR-142-5p was the main cargo of SC-EVs. Next, luciferase reporter gene and phenotyping experiments confirmed the direct targets of miR-142-5p. RESULTS: The contents and granule sizes of plasma EVs were significantly greater in rats with chronic sciatic nerve constriction injury (CCI)than in sham rats. Administration of the EV biogenesis inhibitor GW4869 ameliorated memory impairment in CCI rats and reversed CCI-associated dendritic spine damage. Notably, during CCI stress, SC-EVs could be transferred into the brain through the circulation and accumulate in the hippocampal CA1-CA3 regions. miR-142-5p was the main cargo wrapped in SC-EVs and mediated the development of CCI-associated memory impairment. Furthermore, α-actinin-4 (ACTN4), ELAV-like protein 4 (ELAVL4) and ubiquitin-specific peptidase 9 X-linked (USP9X) were demonstrated to be important downstream target genes for miR-142-5p-mediated regulation of dendritic spine damage in hippocampal neurons from CCI rats. CONCLUSION: Together, these findings suggest that SCs-EVs and/or their cargo miR-142-5p may be potential therapeutic targets for memory impairment associated with CNP.


Assuntos
Vesículas Extracelulares , MicroRNAs , Neuralgia , Ratos , Animais , MicroRNAs/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Células de Schwann/metabolismo , Vesículas Extracelulares/metabolismo
10.
Hepatol Int ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683274

RESUMO

BACKGROUND: Droplet digital PCR (ddPCR) is increasingly used in diagnosing clinical pathogens, but its effectiveness in cirrhosis patients with suspected ascites infection remains uncertain. METHODS: The diagnostic performance of ddPCR was assessed in 305 ascites samples, utilizing culture and clinical composite standards. The quantitative value and potential clinical impact of ddPCR were further analyzed in patients with spontaneous bacterial peritonitis. RESULTS: With culture standards, ddPCR demonstrated a sensitivity of 86.5% and specificity of 83.2% for bacterial or fungal detection. After adjustment of clinical composite criteria, specificity increased to 96.4%. Better diagnostic performance for all types of targeted pathogens, particularly fungi, was observed with ddPCR compared to culture, and more polymicrobial infections were detected (30.4% versus 5.7%, p < 0.001). Pathogen loads detected by ddPCR correlated with white blood cell count in ascites and blood, as well as polymorphonuclear cell (PMN) count in ascites, reflecting infection status rapidly. A positive clinical impact of 55.8% (43/77) was observed for ddPCR, which was more significant among patients with PMN count ≤ 250/mm3 in terms of medication adjustment and new diagnosis. ddPCR results for fungal detection were confirmed by clinical symptoms and other microbiological tests, which could guide antifungal therapy and reduce the risk of short-term mortality. CONCLUSIONS: ddPCR, with appropriate panel design, has advantages in pathogen detection and clinical management of ascites infection, especially for patients with fungal and polymicrobial infections. Patients with atypical spontaneous bacterial peritonitis benefited more from ddPCR.

11.
World J Hepatol ; 16(3): 344-352, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577527

RESUMO

Succinylation is a highly conserved post-translational modification that is processed via enzymatic and non-enzymatic mechanisms. Succinylation exhibits strong effects on protein stability, enzyme activity, and transcriptional regulation. Protein succinylation is extensively present in the liver, and increasing evidence has demonstrated that succinylation is closely related to hepatic metabolism. For instance, histone acetyltransferase 1 promotes liver glycolysis, and the sirtuin 5-induced desuccinylation is involved in the regulation of the hepatic urea cycle and lipid metabolism. Therefore, the effects of succinylation on hepatic glucose, amino acid, and lipid metabolism under the action of various enzymes will be discussed in this work. In addition, how succinylases regulate the progression of different liver diseases will be reviewed, including the desuccinylation activity of sirtuin 7, which is closely associated with fatty liver disease and hepatitis, and the actions of lysine acetyltransferase 2A and histone acetyltransferase 1 that act as succinyltransferases to regulate the succinylation of target genes that influence the development of hepatocellular carcinoma. In view of the diversity and significance of protein succinylation, targeting the succinylation pathway may serve as an attractive direction for the treatment of liver diseases.

12.
Medicine (Baltimore) ; 103(14): e37588, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579095

RESUMO

BACKGROUND: Thyroid surgery involves the partial or complete removal of the thyroid gland and is a frequently performed surgical procedure. The adoption of robots, equipped with flexible and stable operating systems, has garnered acceptance among numerous surgeons for their capability to enable precise anatomical dissection in thyroid surgery. To gain a comprehensive insight into the present research landscape of robot-assisted thyroid surgery, this paper endeavored to conduct a thorough analysis of the field through bibliometric analysis. METHODS: Relevant literature pertaining to robot-assisted thyroid surgery was retrieved from the Web of Science Core Collection (WOSCC) database, spanning from the inception of WOSCC to October 17, 2022. Visual analyses of publication quantity, distribution across countries/regions, institutions/organizations, authorship, journals, references, and keywords were conducted using Microsoft Excel, the bibliometrix package in R, Citescape, and VOSviewer software. RESULTS: A total of 505 articles from 406 institutions in 36 countries/regions were included. South Korea emerged with highest number of publications. Notably, Professor CHUNG WY from Yonsei University in South Korea and the journal "Surg Endosc" stood out with the most publications. The current research landscape indicated significant interest in endoscopic thyroidectomy, surgical procedures, and the axillary approach. In addition, transoral robotic thyroidectomy (TROT), and learning curve (LC) were recognized as research frontiers, representing potential future hotspots in this field. CONCLUSION: This study marks the first bibliometric analysis of the literature on robot-assisted thyroid surgery. The results highlight endoscopic thyroidectomy, surgical procedures, and the axillary approach as current research hotspots, with TROT and LC identified as potential future research hotspots.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Glândula Tireoide/cirurgia , Tireoidectomia , Bibliometria
13.
Carbohydr Polym ; 332: 121935, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431402

RESUMO

A novel cellulose composite (denoted as PEI@MMA-1) with porous interconnected structure was prepared by adsorbing methyl cellulose (MC) onto microcrystalline cellulose (MCC) and cross-linking polyethyleneimine (PEI) with MCC by the action of epichlorohydrin, which had the excellent adsorption property, wettability and elasticity. The performances of PEI@MMA-1 composite for removing tetracycline (TC), Cu2+ and coexistent pollutant (TC and Cu2+ mixture) were systematically explored. For single TC or Cu2+ contaminant, the maximum adsorption capacities were 75.53 and 562.23 mg/g at 30 °C, respectively, while in the dual contaminant system, they would form complexes and Cu2+ could play a "bridge" role to remarkably promote the adsorption of TC with the maximum adsorption capacities of 281.66 and 253.58 mg/g for TC and Cu2+. In addition, the adsorption kinetics, isotherms and adsorption mechanisms of single-pollutant and dual-pollutant systems have been thoroughly investigated. Theoretical calculations indicated that the amide group of TC molecule with the assistance of Cu2+ interacted with the hydroxyl group of PEI@MMA-1 composite to enhance the TC adsorption capacity. Cycle regeneration and fixed bed column experiments revealed that the PEI@MMA-1 possessed the excellent stability and utility. Current PEI@MMA-1 cellulose composite exhibited a promising application for remediation of heavy metals and antibiotics coexistence wastewater.


Assuntos
Celulose/análogos & derivados , Cobre , Polietilenoimina/análogos & derivados , Poluentes Químicos da Água , Cobre/química , Adsorção , Poluentes Químicos da Água/química , Tetraciclina/química , Antibacterianos , Íons , Cinética
14.
Biotechnol Biofuels Bioprod ; 17(1): 38, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454489

RESUMO

BACKGROUND: Glycerol, as a by-product, mainly derives from the conversion of many crops to biodiesel, ethanol, and fatty ester. Its bioconversion to 1,3-propanediol (1,3-PDO) is an environmentally friendly method. Continuous fermentation has many striking merits over fed-batch and batch fermentation, such as high product concentration with easy feeding operation, long-term high productivity without frequent seed culture, and energy-intensive sterilization. However, it is usually difficult to harvest high product concentrations. RESULTS: In this study, a three-stage continuous fermentation was firstly designed to produce 1,3-PDO from crude glycerol by Clostridium butyricum, in which the first stage fermentation was responsible for providing the excellent cells in a robust growth state, the second stage focused on promoting 1,3-PDO production, and the third stage aimed to further boost the 1,3-PDO concentration and reduce the residual glycerol concentration as much as possible. Through the three-stage continuous fermentation, 80.05 g/L 1,3-PDO as the maximum concentration was produced while maintaining residual glycerol of 5.87 g/L, achieving a yield of 0.48 g/g and a productivity of 3.67 g/(L·h). Based on the 14 sets of experimental data from the first stage, a kinetic model was developed to describe the intricate relationships among the concentrations of 1,3-PDO, substrate, biomass, and butyrate. Subsequently, this kinetic model was used to optimize and predict the highest 1,3-PDO productivity of 11.26 g/(L·h) in the first stage fermentation, while the glycerol feeding concentration and dilution rate were determined to be 92 g/L and 0.341 h-1, separately. Additionally, to achieve a target 1,3-PDO production of 80 g/L without the third stage fermentation, the predicted minimum volume ratio of the second fermenter to the first one was 11.9. The kinetics-based two-stage continuous fermentation was experimentally verified well with the predicted results. CONCLUSION: A novel three-stage continuous fermentation and a kinetic model were reported. Then a simpler two-stage continuous fermentation was developed based on the optimization of the kinetic model. This kinetics-based development of two-stage continuous fermentation could achieve high-level production of 1,3-PDO. Meanwhile, it provides a reference for other bio-chemicals production by applying kinetics to optimize multi-stage continuous fermentation.

15.
Materials (Basel) ; 17(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38473687

RESUMO

Solid oxide electrolysis cell (SOEC) industrialization has been developing for many years. Commercial materials such as 8 mol% Y2O3-stabilized zirconia (YSZ), Gd0.1Ce0.9O1.95 (GDC), La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), La0.6Sr0.4CoO3-δ (LSC), etc., have been used for many years, but the problem of mismatched thermal expansion coefficients of various materials between cells has not been fundamentally solved, which affects the lifetime of SOECs and restricts their industry development. Currently, various solutions have been reported, such as element doping, manufacturing defects, and introducing negative thermal expansion coefficient materials. To promote the development of the SOEC industry, a direct treatment method for commercial materials-quenching and doping-is reported to achieve the controllable preparation of the thermal expansion coefficient of commercial materials. The quenching process only involves the micro-treatment of raw materials and does not have any negative impact on preparation processes such as powder slurry and sintering. It is a simple, low-cost, and universal research strategy to achieve the controllable preparation of the thermal expansion coefficient of the commercial material La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) through a quenching process by doping elements and increasing oxygen vacancies in the material. Commercial LSCF materials are heated to 800 °C in a muffle furnace, quickly removed, and cooled and quenched in 3.4 mol/L of prepared Y(NO3)3. The thermal expansion coefficient of the treated material can be reduced to 13.6 × 10-6 K-1, and the blank sample is 14.1 × 10-6 K-1. In the future, it may be possible to use the quenching process to select appropriate doping elements in order to achieve similar thermal expansion coefficients in SOECs.

16.
Adv Mater ; 36(25): e2314097, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466829

RESUMO

Planarly aligning 2D platelets is challenging due to their additional orientational freedom compared to 1D materials. This study reports a sequential dual-alignment approach, employing an extrusion-printing-induced shear force and rotating-magnetic-field-induced force couple for platelet planarly alignment in a yield-stress support bath. It is hypothesized that the partial alignment induced by a directional shear force facilitates subsequent axial rotation of the platelets for planar alignment under an external force couple, resulting in a synergistic alignment effect. This sequential dual-alignment approach achieves better planar alignment of 2D modified hexagonal boron nitride (mhBN). Specifically, the thermal conductivity of the 40 wt% mhBN/epoxy composite is significantly higher (692%) than that of unaligned composites, surpassing the cumulative effect of individual methods (only 133%) with a 5 times more synergistic effect. For 30, 40, and 50 wt% mhBN composites, the thermal conductivity values (5.9, 9.5, and 13.8 W m-1 K-1) show considerable improvement compared to the previously reported highest values (5.3, 6.6, and 8.6 W m-1 K-1). Additionally, a 3D mhBN/epoxy heat sink is printed and evaluated to demonstrate the feasibility of device fabrication. The approach enables the planar alignment of electrically or thermally conducting 2D fillers during 3D fabrication.

17.
Langmuir ; 40(14): 7680-7691, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551605

RESUMO

Due to incommensurability between initial thickness and interdomain distance, thermal annealing inevitably produces relief surface terraces (islands and holes) of various morphologies in thin films of block copolymers. We have demonstrated three kinds of surface terraces in blend films: polygrain terraces with diffuse edges, polygrain terraces with step edges, and pseudo-monograin terraces with island coarsening. The three morphologies were obtained by three different thermal histories, respectively. The thermal histories were imposed on blend films, which were prepared by mixing a homopolystyrene (hPS, 6.1 kg/mol) with a weakly segregated, symmetry polystyrene-block poly(methyl methacrylate) (PS-b-PMMA, 42 kg/mol) followed by spin coating. At a given weight-fraction ratio of PS-b-PMMA/hPS = 75/25, the interior of the blend films forms parallel cylinders. Nevertheless, the surface of the blend films is always dominated by a skin layer of perforations, which epitaxially grow on top of parallel cylinders. By oxygen plasma etching at various time intervals to probe interior nanodomains, the epitaxial relationship between surface perforations and parallel cylinders has been identified by a scanning electron microscope.

18.
J Environ Manage ; 356: 120635, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508001

RESUMO

The transport sector proves a major energy consumer in China, but improving energy-saving performance in China's provincial transport sector from the lifecycle perspective remains unresolved. Thus, this study employs the environmentally extended multi-region input-output (MRIO) method, structural path analysis, and the newest MRIO table of China from 2017, to investigate how to improve the energy-saving performance from final demand structure, supply chain, and pathway perspectives. The relevant results are threefold. (1) Regarding the final demand structure level, the embodied energy consumption of China's transport sector is predominantly driven by investment from the production side, while that of the consumption side is primarily caused by exports. (2) At the supply chain level, production-side embodied energy consumption primarily occurs along a three-echelon supply chain, while that from the consumption side mostly occurs via a two-echelon supply chain. (3) At the pathway level, the production-side energy-saving performance of China's provincial transport sector is dominated by two pathways along the construction sector, including transport sector → construction sector → final demands, and transport sector → intermediate inputs → construction sector → final demands, while that of the consumption side is chiefly determined by three pathways along internal transportation chains.


Assuntos
Desenvolvimento Econômico , Investimentos em Saúde , China , Meios de Transporte , Dióxido de Carbono/análise
19.
Artigo em Inglês | MEDLINE | ID: mdl-38504012

RESUMO

Witnessing violent or traumatic events is common during childhood and adolescence and could cause detrimental effects such as increased risks of psychiatric disorders. This stressor could be modeled in adolescent laboratory animals using the chronic witnessing social defeat (CWSD) paradigm, but the behavioral consequences of CWSD in adolescent animals remain to be validated for cognitive, anxiety-like, and depression-like behaviors and, more importantly, the underlying neural mechanisms remain to be uncovered. In this study, we first established the CWSD model in adolescent male mice and found that CWSD impaired cognitive function and increased anxiety levels and that these behavioral deficits persisted into adulthood. Based on the dorsal-ventral functional division in hippocampus, we employed immediate early gene c-fos immunostaining after behavioral tasks and found that CWSD-induced cognition deficits were associated with dorsal CA3 overactivation and anxiety-like behaviors were associated with ventral CA3 activity reduction. Indeed, chemogenetic activation and inhibition of dorsal CA3 neurons mimicked and reversed CWSD-induced recognition memory deficits (not anxiety-like behaviors), respectively, whereas both inhibition and activation of ventral CA3 neurons increased anxiety-like behaviors in adolescent mice. Finally, chronic administration of vortioxetine (a novel multimodal antidepressant) successfully restored the overactivation of dorsal CA3 neurons and the cognitive deficits in CWSD mice. Together, our findings suggest that dorsal CA3 overactivation mediates CWSD-induced recognition memory deficits in adolescent male mice, shedding light on the pathophysiology of adolescent CWSD-induced adverse effects and providing preclinical evidence for early treatment of stress-induced cognitive deficits.

20.
Pediatr Neonatol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38523015

RESUMO

OBJECTIVE: To study the relationship between umbilical cord blood vitamin A (VA) and neonatal lung diseases and explore the impact of umbilical cord blood VA on neonatal lung diseases. METHOD: Umbilical vein blood was collected at birth, and its VA content was measured. According to the VA levels in umbilical cord blood, a VA deficiency (VAD) group, a marginal deficiency group and a normal group were created and followed up until 28 days after birth. RESULTS: The umbilical cord blood VA level in the neonatal group with lung disease was 0.13 ± 0.05 mg/L, while the result for the VA level in the non-lung disease group was 0.15 ± 0.05 mg/L. The umbilical cord blood VA levels in the neonatal lung disease group were significantly lower than those in the non-lung disease group. The incidence of neonatal pulmonary diseases was highest in the VAD group, and the incidence decreased as the level of VA in umbilical cord blood increased. Umbilical cord blood VAD and premature birth were found to be independent risk factors for neonatal respiratory disease. CONCLUSION: Umbilical cord blood VAD and premature birth are independent risk factors for neonatal pulmonary diseases. The lower the level of VA in umbilical cord blood, the more susceptible infants will be to neonatal respiratory infections in the neonatal period.

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