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1.
Small ; 20(27): e2310530, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38317526

RESUMO

Rechargeable aprotic Li-CO2 batteries have aroused worldwide interest owing to their environmentally friendly CO2 fixation ability and ultra-high specific energy density. However, its practical applications are impeded by the sluggish reaction kinetics and discharge product accumulation during cycling. Herein, a flexible composite electrode comprising CoSe2 nanoparticles embedded in 3D carbonized melamine foam (CoSe2/CMF) for Li-CO2 batteries is reported. The abundant CoSe2 clusters can not only facilitate CO2 reduction/evolution kinetics but also serve as Li2CO3 nucleation sites for homogeneous discharge product growth. The CoSe2/CMF-based Li-CO2 battery exhibits a large initial discharge capacity as high as 5.62 mAh cm-2 at 0.05 mA cm-2, a remarkably small voltage gap of 0.72 V, and an ultrahigh energy efficiency of 85.9% at 0.01 mA cm-2, surpassing most of the noble metal-based catalysts. Meanwhile, the battery demonstrates excellent cycling stability of 1620 h (162 cycles) at 0.02 mA cm-2 with an average overpotential of 0.98 V and energy efficiency of 85.4%. Theoretical investigations suggest that this outstanding performance is attributed to the suitable CO2/Li adsorption and low Li2CO3 decomposition energy. Moreover, flexible Li-CO2 pouch cell with CoSe2/CMF cathode displays stable power output under different bending deformations, showing promising potential in wearable electronic devices.

2.
Small ; 20(25): e2309906, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38221704

RESUMO

On-site hydrogen production from liquid organic hydrogen carriers e.g., methanol provides an emerging strategy for the safe storage and transportation of hydrogen. Herein, a catalytic architecture consisting of nickel-cobalt nanoclusters dispersed on gallium nitride nanowires supported by silicon for light-driven hydrogen production from methanol is reported. By correlative microscopic, spectroscopic characterizations, and density functional theory calculations, it is revealed that NiCo nanoclusters work in synergy with GaN nanowires to enable the achievement of a significantly reduced activation energy of methanol dehydrogenation by switching the potential-limiting step from *CHO → *CO to *CH3O → *CH2O. In combination with the marked photothermal effect, a high hydrogen rate of 5.62 mol·gcat-1·h-1 with a prominent turnover frequency of 43,460 h-1 is achieved at 5 Wcm-2 without additional energy input. Remarkably, the synergy between Co and Ni, in combination with the unique surface of GaN, renders the architecture with outstanding resistance to sintering and coking. The architecture thereby exhibits a high turnover number of >16,310,000 over 600 h. Outdoor testing validates the viability of the architecture for active and robust hydrogen evolution under natural concentrated sunlight. Overall, this work presents a promising architecture for on-site hydrogen production from CH3OH by virtually unlimited solar energy.

3.
Small ; : e2311500, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372501

RESUMO

Singlet oxygen (term symbol 1 Δg , hereafter 1 O2 ), a reactive oxygen species, has recently attracted increasing interest in the field of rechargeable batteries and electrocatalysis and photocatalysis. These sustainable energy conversion and storage technologies are of vital significance to replace fossil fuels and promote carbon neutrality and finally tackle the energy crisis and climate change. Herein, the recent progresses of 1 O2 for energy storage and conversion is summarized, including physical and chemical properties, formation mechanisms, detection technologies, side reactions in rechargeable batteries and corresponding inhibition strategies, and applications in electrocatalysis and photocatalysis. The formation mechanisms and inhibition strategies of 1 O2 in particular aprotic lithium-oxygen (Li-O2 ) batteries are highlighted, and the applications of 1 O2 in photocatalysis and electrocatalysis is also emphasized. Moreover, the confronting challenges and promising directions of 1 O2 in energy conversion and storage systems are discussed.

4.
Nat Mater ; 22(7): 853-859, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37349395

RESUMO

III-nitride wide bandgap semiconductors are promising materials for modern optoelectronics and electronics. Their application has progressed greatly thanks to the continuous quality improvements of heteroepitaxial films grown on large-lattice-mismatched foreign substrates. But compared with bulk single crystals, there is still tremendous room for the further improvement of the material quality. Here we show a paradigm to achieve high-quality III-nitride heteroepitaxial films by the controllable discretization and coalescence of columns. By adopting nano-patterned AlN/sapphire templates with regular hexagonal holes, discrete AlN columns coalesce with uniform out-of-plane and in-plane orientations guaranteed by sapphire nitridation pretreatment and the ordered lateral growth of cleavage facets, which efficiently suppresses the regeneration of threading dislocations during coalescence. The density of dislocation etch pits in the AlN heteroepitaxial film reaches 3.3 × 104 cm-2, close to the present available AlN bulk single crystals. This study facilitates the growth of bulk-class quality III-nitride films featuring low cost and scalability.


Assuntos
Óxido de Alumínio , Eletrônica , Semicondutores , Software
5.
Opt Lett ; 49(14): 4058-4061, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008776

RESUMO

A near-resonant excitation strategy is proposed and implemented in a 4-µm-thick GaN microcavity to realize an exciton-polariton condensate/lasing with low threshold. Strong exciton-photon coupling is demonstrated, and polariton lasing is realized with an ultra-low threshold excitation power density of about 13.3 W/cm2 at room temperature. Such an ultra-low threshold is ascribed to the implementation of the near-resonant optical excitation strategy, which enables acceleration of the exciton and polariton relaxation and suppression of the heat generation in the cavity, thereby reducing the energy loss and enhance the cavity excitation efficiency.

6.
Inorg Chem ; 63(4): 2275-2281, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38226409

RESUMO

In recent years, there has been a surge in research enthusiasm on searching for solid-state nonlinear optical (NLO) switching materials in halide perovskites owing to their exceptional structural flexibility, compositional diversity, and broad property tenability. However, the majority of reported halide perovskite NLO switching materials contain toxic elements (e.g., Pb), which raise significant environmental concerns. Herein, we present a novel lead-free multilayered halide perovskite NLO switching material, (BA)2(EA)2Sn3Br10 (1, where BA is butylammonium and EA is ethylammonium). Driven by the stereochemically active lone-pair electrons of the Sn2+ cation and the cage-confined effect of EA rotators, 1 undergoes a phase transition with symmetry breaking from P4/mnc to Cmc21, which gives rise to a highly efficient modulation of the quadratic NLO property (0.7 times that of KH2PO4) at a high temperature of 353 K. Furthermore, crystallographic investigation combined with theoretical calculations reveals that the efficient modulation of NLO properties in 1 stems from the synergistic effects between stereochemically active lone pair-induced octahedral distortions and order/disorder transformation of organic cations. This study opens up an instructive avenue for designing and advancing environmentally friendly solid-state NLO switches in halide perovskites.

7.
Entropy (Basel) ; 26(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38920489

RESUMO

In most silent speech research, continuously observing tongue movements is crucial, thus requiring the use of ultrasound to extract tongue contours. Precisely and in real-time extracting ultrasonic tongue contours presents a major challenge. To tackle this challenge, the novel end-to-end lightweight network DAFT-Net is introduced for ultrasonic tongue contour extraction. Integrating the Convolutional Block Attention Module (CBAM) and Attention Gate (AG) module with entropy-based optimization strategies, DAFT-Net establishes a comprehensive attention mechanism with dual functionality. This innovative approach enhances feature representation by replacing traditional skip connection architecture, thus leveraging entropy and information-theoretic measures to ensure efficient and precise feature selection. Additionally, the U-Net's encoder and decoder layers have been streamlined to reduce computational demands. This process is further supported by information theory, thus guiding the reduction without compromising the network's ability to capture and utilize critical information. Ablation studies confirm the efficacy of the integrated attention module and its components. The comparative analysis of the NS, TGU, and TIMIT datasets shows that DAFT-Net efficiently extracts relevant features, and it significantly reduces extraction time. These findings demonstrate the practical advantages of applying entropy and information theory principles. This approach improves the performance of medical image segmentation networks, thus paving the way for real-world applications.

8.
Angew Chem Int Ed Engl ; 63(16): e202400011, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38409577

RESUMO

Light-driven hydrogen production from biomass derivatives offers a path towards carbon neutrality. It is often however operated with the limitations of sluggish kinetics and severe coking. Herein, a disruptive air-promoted strategy is explored for efficient and durable light-driven hydrogen production from ethanol over a core/shell Cr2O3@GaN nanoarchitecture. The correlative computational and experimental investigations show ethanol is energetically favorable to be adsorbed on the Cr2O3@GaN interface, followed by dehydrogenation toward acetaldehyde and protons by photoexcited holes. The released protons are then consumed for H2 evolution by photogenerated electrons. Afterward, O2 can be evolved into active oxygen species and promote the deprotonation and C-C cleavage of the key C2 intermediate, thus significantly lowering the reaction energy barrier of hydrogen evolution and removing the carbon residual with inhibited overoxidation. Consequently, hydrogen is produced at a high rate of 76.9 mole H2 per gram Cr2O3@GaN per hour by only feeding ethanol, air, and light, leading to the achievement of a turnover number of 266,943,000 mole H2 per mole Cr2O3 over a long-term operation of 180 hours. Notably, an unprecedented light-to-hydrogen efficiency of 17.6 % is achieved under concentrated light illumination. The simultaneous generation of aldehyde from ethanol dehydrogenation enables the process more economically promising.

9.
Nat Mater ; 21(11): 1263-1268, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36109673

RESUMO

The production of large-area twisted bilayer graphene (TBG) with controllable angles is a prerequisite for proceeding with its massive applications. However, most of the prevailing strategies to fabricate twisted bilayers face great challenges, where the transfer methods are easily stuck by interfacial contamination, and direct growth methods lack the flexibility in twist-angle design. Here we develop an effective strategy to grow centimetre-scale TBG with arbitrary twist angles (accuracy, <1.0°). The success in accurate angle control is realized by an angle replication from two prerotated single-crystal Cu(111) foils to form a Cu/TBG/Cu sandwich structure, from which the TBG can be isolated by a custom-developed equipotential surface etching process. The accuracy and consistency of the twist angles are unambiguously illustrated by comprehensive characterization techniques, namely, optical spectroscopy, electron microscopy, photoemission spectroscopy and photocurrent spectroscopy. Our work opens an accessible avenue for the designed growth of large-scale two-dimensional twisted bilayers and thus lays the material foundation for the future applications of twistronics at the integration level.

10.
Phys Chem Chem Phys ; 25(31): 21037-21044, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37522183

RESUMO

The discovery of superconductivity in layered MgB2 has renewed interest in the search for high-temperature conventional superconductors, leading to the synthesis of numerous hydrogen-dominated materials with high critical temperatures (Tc) under high pressures. However, achieving a high-Tc superconductor under ambient pressure remains a challenging goal. In this study, we propose a novel approach to realize a high-temperature superconductor under ambient pressure by introducing a hexagonal H monolayer into the hexagonal close-packed magnesium lattice, resulting in a new and stable few-hydrogen metal-bonded layered magnesium hydride (Mg4)2H1. This compound exhibits superior ductility compared to multi-hydrogen, cuprate, and iron-based superconductors due to its metallic bonding. Our unconventional strategy diverges from the conventional design principles used in hydrogen-dominated covalent high-temperature superconductors. Using anisotropic Migdal-Eliashberg equations, we demonstrate that the stable (Mg4)2H1 compound is a typical phonon-mediated superconductor, characterized by strong electron-phonon coupling and an excellent Tc of 37 K under ambient conditions, comparable to that of MgB2. Our findings not only present a new pathway for exploring high-temperature superconductors but also provide valuable insights for future experimental synthesis endeavors.

11.
BMC Pregnancy Childbirth ; 23(1): 725, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37821857

RESUMO

BACKGROUND: The placenta serves as the sole maternal organ responsible for transmitting nutrients to the fetus, playing a crucial role in supporting standard fetal growth and development. To date, only a small number of studies have investigated the impact of maternal gestational weight gain and lipid concentrations on placental development. This study aimed to explore the influence of weight gain during pregnancy and lipid levels in the second trimester on placental weight, volume, and the placental weight ratio. METHODS: This birth cohort study encompassed 1,358 mother-child pairs. Placental data for each participant was gathered immediately post-delivery, and the study incorporated data on gestational weight gain throughout pregnancy and lipid profiles from the mid-trimester. A linear regression model was employed to assess the correlations between gestational weight gain, mid-trimester lipid levels, and metrics such as placental weight, placental volume, and the placental-to-birth weight ratio (PFR). RESULTS: In the study groups of pre-pregnancy underweight, normal weight, and overweight, the placental weight increased by 4.93 g (95% CI: 1.04-8.81), 2.52 g (95% CI: 1.04-3.99), and 3.30 g (95% CI: 0.38-6.22) per 1 kg of gestational weight gain, respectively. Within the pre-pregnancy underweight and normal weight groups, the placental volume increased by 6.79 cm^3 (95% CI: 3.43-10.15) and 2.85 cm^3 (95% CI: 1.31-4.39) per 1 kg of gestational weight gain, respectively. Additionally, placental weight exhibited a positive correlation with triglyceride (TG) levels (ß = 9.81, 95% CI: 3.28-16.34) and a negative correlation with high-density lipoprotein (HDL-C) levels (ß = - 46.30, 95% CI: - 69.49 to - 23.11). Placental volume also showed a positive association with TG levels (ß = 14.54, 95% CI: 7.69-21.39). Conversely, PFR demonstrated a negative correlation with increasing HDL-C levels (ß = - 0.89, 95% CI: - 1.50 to - 0.27). CONCLUSIONS: Gestational weight gain was significantly correlated with both placental weight and volume. This association was especially pronounced in women who, prior to pregnancy, were underweight or of normal weight. Additionally, TG and HDL-C levels during the mid-trimester were linked to placental development.


Assuntos
Ganho de Peso na Gestação , Placenta , Feminino , Humanos , Gravidez , Peso ao Nascer , Estudos de Coortes , População do Leste Asiático , Lipídeos , Placenta/embriologia , Magreza , Tamanho do Órgão
12.
Arch Gynecol Obstet ; 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773466

RESUMO

BACKGROUND: It has been suggested that gestational diabetes mellitus (GDM) alters the growth trajectory of a fetus and increases the risk of abnormal birth weight. In spite of this, there is still a significant debate regarding the mode and optimal timing of diagnosing this condition. Our aim was to determine fetal growth velocity and birth biometry in pregnant women with GDM at varying risk levels. METHODS: We conducted a cohort study involving 1023 pregnant women at a maternity hospital in Ma'anshan, China. All women completed an oral glucose tolerance test at 24-28 weeks' gestation. We measured fetal head circumference (HC), femoral length (FL), abdominal circumference (AC), biparietal diameter (BPD), and estimate fetal weight (EFW) by ultrasound at 17, 24, 31, and 35 weeks' gestation, respectively. RESULTS: Overall, 5115 ultrasound scans were performed. Among both low-risk and medium-high-risk pregnant women at 17-24 weeks' gestation, GDM exposure was associated with an increase in fetal growth velocity. Neonates born to women with GDM at medium-high risk had significantly larger birth weights than those born to women without GDM, while this was not observed in women at low risk. CONCLUSION: In medium-high-risk pregnant women, exposure to GDM has a greater effect on the fetus, leading to abnormal fetal growth velocity that lasts beyond week 24. It is evident from our results that the effects of GDM on fetal growth differ between medium-high-risk pregnant women and low-risk pregnant women, and therefore a different screening program based on the risk factor for GDM is warranted.

13.
Environ Geochem Health ; 45(11): 8187-8202, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37552412

RESUMO

We aimed to characterize the association between air pollutants exposure and periodontal diseases outpatient visits and to explore the interactions between ambient air pollutants and meteorological factors. The outpatient visits data of several large stomatological and general hospitals in Hefei during 2015-2020 were collected to explore the relationship between daily air pollutants exposure and periodontal diseases by combining Poisson's generalized linear model (GLMs) and distributed lag nonlinear model (DLNMs). Subgroup analysis was performed to identify the vulnerability of different populations to air pollutants exposure. The interaction between air pollutants and meteorological factors was verified in both multiplicative and additive interaction models. An interquartile range (IQR) increased in nitrogen dioxide (NO2) concentration was associated with the greatest lag-specific relative risk (RR) of gingivitis at lag 3 days (RR = 1.087, 95% CI 1.008-1.173). Fine particulate matter (PM2.5) exposure also increased the risk of periodontitis at the day of exposure (RR = 1.049, 95% CI 1.004-1.096). Elderly patients with gingivitis and periodontitis were both vulnerable to PM2.5 exposure. The interaction analyses showed that exposure to high levels of NO2 at low temperatures was related to an increased risk of gingivitis, while exposure to high levels of NO2 and PM2.5 may also increase the risk of gingivitis and periodontitis in the high-humidity environment, respectively. This study supported that NO2 and PM2.5 exposure increased the risk of gingivitis and periodontitis outpatient visits, respectively. Besides, the adverse effects of air pollutants exposure on periodontal diseases may vary depending on ambient temperature and humidity.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Gengivite , Doenças Periodontais , Periodontite , Humanos , Idoso , Dióxido de Nitrogênio/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Material Particulado/análise , Conceitos Meteorológicos , Doenças Periodontais/etiologia , Doenças Periodontais/induzido quimicamente , Periodontite/induzido quimicamente , Gengivite/induzido quimicamente , Gengivite/epidemiologia , China , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise
14.
Phys Chem Chem Phys ; 24(4): 2110-2117, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35019921

RESUMO

Very recently, the septuple-atomic-layer MoSi2N4 has been successfully synthesized by a chemical vapor deposition method. However, pristine MoSi2N4 exhibits some shortcomings, including poor visible-light harvesting capability and a low separation rate of photo-excited electron-hole pairs, when it is applied in water splitting to produce hydrogen. Fortunately, we find that MoSi2N4 can be considered as a good co-catalyst to be stacked with InSe forming an efficient heterostructure photocatalyst. Here, the electronic and photocatalytic properties of the two-dimensional (2D) InSe/MoSi2N4 heterostructure have been systematically investigated by density functional theory for the first time. The results demonstrate that 2D InSe/MoSi2N4 has a type-II band alignment with a favourable direct bandgap of 1.61 eV and exhibits suitable band edge positions for overall water splitting. Particularly, 2D InSe/MoSi2N4 has high electron mobility (104 cm2 V-1 s-1) and shows a noticeable optical absorption coefficient (105 cm-1) in the visible-light region of the solar spectrum. These brilliant properties declare that 2D InSe/MoSi2N4 is a potential photocatalyst for overall water splitting.

15.
Appl Opt ; 61(6): C13-C19, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35200993

RESUMO

Spatial heterodyne scanning imaging combines the advantages of spatial heterodyne spectroscopy and imaging technology. It can obtain images and spectral information simultaneously with the characteristics of high spectral resolution, high flux, and small volume and can achieve spectral restoration of all target points in the measured area through scan imaging only once. When two-dimensional spatial information and one-dimensional spectral information are obtained, the imaging spectrum data cube is generated. Using MATLAB and ZEMAX as simulation software, image information with interference fringes was constructed, and the distribution of interference information was explored. A potassium lamp, xenon lamp, and tungsten lamp were used as different light sources to perform validation. Because of the influence of the scanning displacement error on the accuracy of interference information extraction, an algorithm for image spectrum reconstruction is proposed based on the principle of distribution of interference information. The speed-up robust features algorithm was used for image registration to improve accuracy. The experimental results show that the spectral information under the three light sources can be reconstructed, which corresponds to the standard spectrum from the optical fiber spectrometer. The feasibility of this imaging spectrum reconstruction has been preliminarily verified, and the spectral information of the desired target can be directly extracted from the data cube.

16.
BMC Anesthesiol ; 22(1): 181, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35698062

RESUMO

BACKGROUND: Internal jugular vein catheterization is widely used in clinical practice, and there are many related studies on internal jugular vein catheterization. However, the omohyoid muscle, which is adjacent to the internal jugular vein, is a rarely mentioned muscle of the infrahyoid muscles group. The purpose of this study is to explore the anatomical relationship between the omohyoid muscle and the internal jugular vein on ultrasound guidance and provide a theoretical reference for jugular puncture and catheterization. METHODS: The study included 30 volunteers. The volunteer's head lay in the neutral position and was then turned to the left at an angle of 30°, 45° and 60° with the bed surface, as verified using an adjustable protractor. A high-frequency ultrasound probe (6-14 Hz) was used to examine the plane of the apex of sternocleidomastoid triangle (PAST), the triangle consists of anatomical landmarks: a base was clavicle, its sides - heads of sternocleidomastoid muscle. And the plane of the middle of sternocleidomastoid triangle(PMST) which was a horizontal line, connecting midpoints of both sides. The right omohyoid muscle (OM) and the right internal jugular vein (IJV) were observed and recorded for statistical analysis. RESULTS: There were statistically significant differences in the number of overlapping cases of OM and IJV at each head rotation angle between the PAST and PMST groups. There were statistically significant differences between the angles which OM and IJV centre point line and the left horizontal position of the PAST and PMST at different body angles. CONCLUSION: The traditional middle route puncture point is the apex of the sternocleidomastoid triangle, which can effectively avoid injury to the omohyoid muscle, to an extent. TRAIL REGISTRATION: ChiCTR2000034233 , Registered 29/06/2020. www. Chinese Clinical Trial Registry.gov.


Assuntos
Cateterismo Venoso Central , Veias Jugulares , Músculos do Pescoço , Cabeça , Humanos , Veias Jugulares/diagnóstico por imagem , Músculos , Músculos do Pescoço/anatomia & histologia , Ultrassonografia
17.
Int J Behav Med ; 29(4): 416-425, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34581977

RESUMO

BACKGROUND: The global spread of COVID-19 has brought immense psychological distress and sleep problems to those affected. This study examined the mediating role of rumination in the direct association between COVID-19 stressors and poor sleep quality and the moderating roles of emotion regulation strategies. METHOD: A cross-sectional online survey study was conducted in China during the early outbreak of the pandemic. A total of 1106 Chinese college students (Mage = 19.58, SD = 1.61) completed measures of COVID-19 stressors, rumination, emotion regulation strategies (i.e., cognitive reappraisal and expressive suppression), and poor sleep quality. RESULTS: COVID-19 stressors were positively associated with poor sleep quality (ß = .431, p < .001), and rumination partially mediated this association. The mediation effect accounted for 70.93% of the total effect of COVID-19 stressors on poor sleep quality. Moreover, cognitive reappraisal moderated the relation between COVID-19 stressors and rumination, and expressive suppression moderated the association between rumination and poor sleep quality. CONCLUSION: Rumination could be a mechanism by which COVID-19 stressors are linked with poor sleep quality. Cognitive reappraisal might provide desired benefits to improving sleep quality while expressive suppression may do the opposite. Implications for future steps and health interventions are discussed.


Assuntos
COVID-19 , Regulação Emocional , Distúrbios do Início e da Manutenção do Sono , Adulto , Estudos Transversais , Emoções/fisiologia , Humanos , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Qualidade do Sono , Adulto Jovem
18.
Child Youth Serv Rev ; 137: 106493, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35400776

RESUMO

Previous studies have revealed that situational risk factors have a significant influence on the willingness to help. Amidst the COVID-19 pandemic, maybe risk perception of COVID-19 is also correlated to the willingness to help. This study examined the mediating effect of interpersonal alienation and the moderating effect of cognitive reappraisal and expressive suppression in the relationship between risk perception of COVID-19 and willingness to help. Data from a large sample of Chinese college students (N = 2, 163) completed the measures of risk perception of COVID-19, willingness to help, interpersonal alienation, emotion regulation strategies including cognitive reappraisal and expressive suppression. The results indicated that the risk perception of COVID-19 negatively correlated to willingness to help. Interpersonal alienation partially mediated the link between risk perception of COVID-19 and willingness to help. College students' expressive suppression moderated the associations between interpersonal alienation and willingness to help. And who adopted more expressive suppression, the connection between interpersonal alienation and willingness to help was weaker compared to students who reported less expressive suppression. But cognitive reappraisal did not moderate the relationship between risk perception of COVID-19 and interpersonal alienation. Implications of the present paper for theory and practice are discussed.

19.
Immunology ; 162(1): 3-10, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32876334

RESUMO

Hydrogen sulphide (H2 S) is the latest identified small gaseous mediator enabled by its lipophilic nature to freely permeate the biological membranes. Initially, H2 S was recognized by its roles in neuronal activity and vascular relaxation, which makes it an important molecule involved in paracrine signalling pathways. Recently, the immune regulatory function of gasotransmitters, H2 S in particular, is increasingly being appreciated. Endogenous H2 S level has been linked to macrophage activation, polarization and inflammasome formation. Mechanistically, H2 S-induced protein S-sulphydration suppresses several inflammatory pathways including NF-κB and JNK signalling. Moreover, H2 S serves as a potent cellular redox regulator to modulate epigenetic alterations and to promote mitochondrial biogenesis in macrophages. Here in this review, we intend to summarize the recent advancements of H2 S studies in macrophages, and to discuss with focus on the therapeutic potential of H2 S donors by targeting macrophages. The feasibility of H2 S signalling component as a macrophage biomarker under disease conditions would be also discussed.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , NF-kappa B/metabolismo
20.
Adv Funct Mater ; 31(7): 2008452, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33349747

RESUMO

The world-wide spreading of coronavirus disease (COVID-19) has greatly shaken human society, thus effective and fast-speed methods of non-daily-life-disturbance sterilization have become extremely significant. In this work, by fully benefitting from high-quality AlN template (with threading dislocation density as low as ≈6×108 cm-2) as well as outstanding deep ultraviolet (UVC-less than 280 nm) light-emitting diodes (LEDs) structure design and epitaxy optimization, high power UVC LEDs and ultra-high-power sterilization irradiation source are achieved. Moreover, for the first time, a result in which a fast and complete elimination of SARS-CoV-2 (the virus causes COVID-19) within only 1 s is achieved by the nearly whole industry-chain-covered product. These results advance the promising potential in UVC-LED disinfection particularly in the shadow of COVID-19.

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