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The discovery of room-temperature ferromagnetism in van der Waals (vdW) materials opens new avenues for exploring low-dimensional magnetism and its applications in spintronics. Recently, the observation of the room-temperature topological Hall effect in the vdW ferromagnet Fe3GaTe2 suggests the possible existence of room-temperature skyrmions, yet skyrmions have not been directly observed. In this study, real-space imaging was employed to investigate the domain evolution of the labyrinth and skyrmion structure. First, Néel-type skyrmions can be created at room temperature. In addition, the influence of flake thickness and external magnetic field (during field cooling) on both labyrinth domains and the skyrmion lattice is unveiled. Due to the competition between magnetic anisotropy and dipole interactions, the specimen thickness significantly influences the density of skyrmions. These findings demonstrate that Fe3GaTe2 can host room-temperature skyrmions of various sizes, opening up avenues for further study of magnetic topological textures at room temperature.
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With the popularity of smartphones, a large number of "phubbers" have emerged who are engrossed in their phones regardless of the situation. In response to the potential dangers that phubbers face while traveling, this paper proposes a multimodal danger perception network model and early warning system for phubbers, designed for mobile devices. This proposed model consists of surrounding environment feature extraction, user behavior feature extraction, and multimodal feature fusion and recognition modules. The environmental feature module utilizes MobileNet as the backbone network to extract environmental description features from the rear-view image of the mobile phone. The behavior feature module uses acceleration time series as observation data, maps the acceleration observation data to a two-dimensional image space through GADFs (Gramian Angular Difference Fields), and extracts behavior description features through MobileNet, while utilizing statistical feature vectors to enhance the representation capability of behavioral features. Finally, in the recognition module, the environmental and behavioral characteristics are fused to output the type of hazardous state. Experiments indicate that the accuracy of the proposed model surpasses existing methods, and it possesses the advantages of compact model size (28.36 Mb) and fast execution speed (0.08 s), making it more suitable for deployment on mobile devices. Moreover, the developed image-acceleration multimodal phubber hazard recognition network combines the behavior of mobile phone users with surrounding environmental information, effectively identifying potential hazards for phubbers.
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There are limited studies investigating the association between short-term exposure to PM2.5 and incident cardiovascular disease (CVD) cases in China. This study aims to examine the short-term effects of PM2.5 on the incidence of cardiovascular diseases. A combination of Poisson-distribution generalized linear model and distributed lag non-linear model was used to examine the association between short-term exposure to PM2.5 and incident cases of CVD. The results revealed that per 10 µg/m3 increment of PM2.5 would increase the incident CVD cases by 0.147% (Relative Risk: 1.00147, 95% Confidence Interval: 1.00008-1.00286) at a lag of 2 days. The stratified analyses showed higher effects risk in females, older residents (aged 60-75 years), and acute myocardial infarction group (p-value for difference <0.05). This study indicates that short-term exposure to PM2.5 may increase the risk of CVD and highlights the necessity for a higher air quality standard in Yantai, China.
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Poluentes Atmosféricos , Poluição do Ar , Doenças Cardiovasculares , Feminino , Humanos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Material Particulado/toxicidade , Material Particulado/análise , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologiaRESUMO
Few studies have investigated the association between PM2.5 and hypertension among floating populations. We therefore examined the relationship using binary logistic regression. Each grade of increment in the annual average PM2.5 (grade one: ≤15 µg/m3; grade two: 15-25 µg/m3; grade three: 25-35 µg/m3 [Excluding 25]; grade four: ≥35 µg/m3) was associated with an increased risk of hypertension (odds ratio [OR] = 1.081, 95% confidence interval (CI): 1.034-1.129). Among the female floating population (OR = 1.114, 95% CI: 1.030-1.204), those with education level of primary school and below (OR = 1.140, 95% CI: 1.058-1.229), construction workers (OR = 1.228, 95% CI: 1.058-1.426), and those living in the eastern region of China (OR = 1.241, 95% CI: 1.145-1.346) were more vulnerable to PM2.5. These results indicate that PM2.5 is positively associated with hypertension in floating populations. Floating populations who are female, less educated, construction workers, and living in the eastern region of China are more vulnerable to the adverse impacts of PM2.5.
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Poluentes Atmosféricos , Poluição do Ar , Hipertensão , Humanos , Feminino , Masculino , Material Particulado/toxicidade , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Estudos Transversais , Hipertensão/epidemiologia , Hipertensão/etiologia , China/epidemiologia , Exposição AmbientalRESUMO
BACKGROUND: Hepatitis C threatens human health and brings a heavy economic burden. Shandong Province is the second most populous province in China and has uneven regional economic development. Therefore, we analyzed the incidence rate trend and regional differences of hepatitis C in Shandong Province from 2004 to 2021. METHODS: The monthly and annual incidence rates of hepatitis C in Shandong Province from 2022 to 2030 were predicted by fitting Autoregressive Integrated Moving Average model (ARIMA), Long Short-Term Memory (LSTM) and ARIMA-LSTM combined model. RESULTS: From 2004 to 2021, annual new cases of hepatitis C in Shandong Province increased from 635 to 5834, with a total of 61,707 cases. The incidence rate increased from 0.69/100 thousand in 2004 to 6.40/100 thousand in 2019, with a slight decrease in 2020 and 2021. The average annual incidence rate was 3.47/100 thousand. In terms of regional distribution, the hepatitis C incidence rate in Shandong Province was generally high in the west and low in the east. It is estimated that the hepatitis C incidence rate in Shandong Province will be 9.21 per 100 thousand in 2030. CONCLUSION: The hepatitis C incidence rate in Shandong Province showed an increasing trend from 2004 to 2019 and a decreasing trend in 2020 and 2021. Significant regional variations in incidence rate existed. An upward trend in incidence rate is predicted from 2022 to 2030. It is necessary to strengthen the prevention and control of hepatitis C to achieve the goal of eliminating viral hepatitis by 2030.
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Hepatite C , Humanos , Incidência , Hepatite C/epidemiologia , Hepacivirus , China/epidemiologia , Desenvolvimento EconômicoRESUMO
The non-collinear antiferromagnetic Weyl semimetal Mn3X (X = Ga, Ge, Sn) system has attracted a lot of attentions owing to its robust anomalous Hall effect (AHE), large spin Hall angle and small net magnetization at room temperature. The high spin-charge interconversion efficiency makes it a super candidate in topological antiferromagnetic spintronic devices, which could facilitate ultra-fast operation of high-density devices with low energy consumption. In this work, we have realized to obtain different chiral spin structures in Heusler alloy Mn3Ge thin films, which originate from different crystalline orientations. The high-quality (0002)- and (202¯0)-oriented single phase hexagonal Mn3Ge films are achieved by controllable growth, annealing process and ion implantation. The various magnetic properties and AHE behaviors are observed alongaandccrystal axes, equivalent to magnetic field in and out of the inverse triangular spin plane. The observation demonstrates the manipulation of crystal structure accompanied with chiral spin order in a non-collinear antiferromagnetic Mn3Ge film, which is induced by energy conversion and defect introduction. Thein situthermal treatment induces crystal phase rotation up to 90° and robust AHE modulation, which is significantly important and highly desirable for flexible spin memory device applications.
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In order to find new α-glucosidase inhibitors with high efficiency and low toxicity, novel chromone-based benzohydrazide derivatives 6a-6s were synthesized and characterized through 1H NMR, 13C NMR, and HRMS. All the new synthesized compounds were tested for inhibitory activities against α-glucosidase. Compounds 6a-6s with IC50 values ranging from 4.51 ± 0.09 to 27.21 ± 0.83 µM, showed a potential α-glucosidase inhibitory activity as compared to the positive control (acarbose: IC50 = 790.40 ± 0.91 µM). Compound 6i exhibited the highest α-glucosidase inhibitory activity with an IC50 value of 4.51 ± 0.09 µM. Theinteractionbetween α-glucosidase and 6i was further confirmed by enzyme kinetic, fluorescence quenching, circular dichroism, and molecular docking study. In vivo experiment showed that 6i could suppress the rise of blood glucose levels after sucrose loading. The cytotoxicity result indicated that 6i exhibited low cytotoxicity in vitro.
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Inibidores de Glicosídeo Hidrolases , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo , Cromonas/farmacologia , Cromonas/química , Estrutura MolecularRESUMO
To develop novel α-glucosidase inhibitors, a series of chromone-based phenylhydrazone and benzoylhydrazone derivatives were designed, synthesized, and evaluated their inhibitory effects on α-glucosidase. The target compounds were characterized using 1H NMR, 13C NMR, and high-resolution mass spectra. Some of the compounds showed a varying degree of α-glucosidase inhibitory activity with IC50 values ranging from 6.59 ± 0.09 to 158.55 ± 0.87 µM. Among them, compound 5c (IC50 = 6.59 ± 0.09 µM) was the most potent inhibitor by comparison with positive control acarbose (IC50 = 685.11 ± 7.46 µM). Enzyme kinetic, fluorescence analysis, circular dichroism spectra, and molecular docking techniques were employed to explain the underlying molecular mechanisms of 5c inhibition on α-glucosidase. In vivo sucrose-loading test showed that 5c could suppress the rise of blood glucose levels after loading sucrose in normal Kunming mice. The cytotoxicity assay indicated that 5c exhibited low cytotoxicity.
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Hipoglicemiantes , alfa-Glucosidases , Camundongos , Animais , Hipoglicemiantes/química , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo , Relação Estrutura-Atividade , Cromonas/farmacologia , Cromonas/química , Inibidores de Glicosídeo Hidrolases/química , Estrutura MolecularRESUMO
To discover potent α-glucosidase inhibitors, a class of novel triazole-phenylacetamide derivatives (5a-5p) were designed, prepared, and tested for their α-glucosidase inhibitory effects. All tested compounds (5a-5p) displayed a strong α-glucosidase inhibitory activity (IC50 = 6.69 ± 0.18-113.65 ± 2.94 µM) in comparison with the positive control acarbose (IC50 = 723.06 ± 11.26 µM). Thereinto, 5g (IC50 = 6.69 ± 0.18 µM) showed the best anti-α-glucosidase activity and behaved as a mixed-type inhibitor with the value of Ki and Kis to be 1.65 µM and 4.54 µM, respectively. Besides, fluorescence quenching experiment, three-dimensional fluorescence spectra assay, circular dichroism analysis, and molecular docking studies indicated that 5g may inhibit α-glucosidase activity by binding with its active site as well as changing the secondary structure of α-glucosidase. Combined with the inhibition effect on the rise of postprandial blood glucose level and low cytotoxicity of 5g, it could be concluded that these title compounds may play a role as lead compounds to develop novel α-glucosidase inhibitors.
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Inibidores de Glicosídeo Hidrolases , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/química , alfa-Glucosidases/metabolismo , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Triazóis/química , Estrutura Molecular , CinéticaRESUMO
The ability to accurately monitor chiral biological molecules is of great significance for their potential applications in disease diagnosis and virus detection. As the existing chiral detection technologies are mainly relying on an optical method by using left/right circularly polarized light, the universality is low and the operation is complicated. Moreover, large quantity of chiral molecules is required, causing low detection efficiency. Here, a self-assembled monolayer of polypeptides has been fabricated to realize trace detection of chirality based on spin selectivity of photon-electron interaction. We have utilized Kerr technique to detect the rotation angle by the molecular monolayer, which indicates the chirality of polypeptides. The chiral structure of a biological molecule could result in spin-selectivity of electrons and thus influence the interaction between electron spin and light polarization. A Kerr rotation angle of â¼3° has been obviously observed, equivalent to the magneto-optic Kerr effect without magnetic material or magnetic field. Furthermore, we have provided a novel solution to achieve chirality discrimination and amplification simultaneously through an optical fiber. The proposed design is applicable for chiral detection via increasing their differential output signal, which clearly demonstrates a useful strategy toward chirality characterization of biological molecules.
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Elétrons , Campos Magnéticos , Fótons , RotaçãoRESUMO
Urease is a kind of nickel-dependent metalloenzyme, which exists in the biological world widely, and can catalyse the hydrolysis of urea into ammonia and carbon dioxide to provide a nitrogen source for organisms. Urease has important uses in agriculture and medicine because it can catalyse the production of ammonia. Therefore, in this review, metal-based inhibitors of urease will be summarised according to different transition metal ions. Including the urease inhibition, structure-activity relationship, and molecular docking. Importantly, among these reviewed effective urease inhibitors, most of copper metal complexes exhibited stronger urease inhibition with IC50 values ranging from 0.46 µM to 41.1 µM. Significantly, the collected comprehensive information looks forward to providing rational guidance and effective strategies for the development of novel, potent, and safe metal-based urease inhibitors, which are better for practical applications in the future.
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Metaloproteínas , Urease , Amônia , Simulação de Acoplamento Molecular , MetaisRESUMO
The outbreak of the COVID-19 coronavirus epidemic has promoted the development of masked face recognition (MFR). Nevertheless, the performance of regular face recognition is severely compromised when the MFR accuracy is blindly pursued. More facts indicate that MFR should be regarded as a mask bias of face recognition rather than an independent task. To mitigate mask bias, we propose a novel Progressive Learning Loss (PLFace) that achieves a progressive training strategy for deep face recognition to learn balanced performance for masked/mask-free faces recognition based on margin losses. Particularly, our PLFace adaptively adjusts the relative importance of masked and mask-free samples during different training stages. In the early stage of training, PLFace mainly learns the feature representations of mask-free samples. At this time, the regular sample embeddings shrink to the prototype. In the later stage of training, PLFace converges on mask-free samples and further focuses on masked samples until the masked sample embeddings are also gathered in the center of the class. The entire training process emphasizes the paradigm that normal samples shrink first and masked samples gather afterward. Extensive experimental results on popular regular and masked face benchmarks demonstrate the superiority of our PLFace over state-of-the-art competitors.
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The multirelaxation behavior is promising for high-performance dielectric materials based on polarization-controllable high-efficiency electromagnetic attenuation. However, a single polar unit is the main problem that restricts the development of dielectric materials in the field. Herein, by constructing multiple polar units based on nanodomain engineering, enhanced electromagnetic attenuation properties are achieved in La doping BiFeO3 ferroelectric ceramics. A dual-band attenuation with a maximum reflection loss of -43.4 dB together with a wide effective bandwidth (<-10 dB) of 3.3 GHz in X-band, is acquired in Bi0.85 La0.15 FeO3 which just has a thickness of 1.54 mm. A systematic experimental analysis coupled with potential well modeling suggests that the miniaturization of the ferroelectric domain, from micron to nanoscale, induces an additional interface polarization that is capable of responding to microwave frequency, leading to the formation of dual dielectric relaxation. The way that intrinsic polar unit induces another polar unit through size effect to obtain multiple contributions of electromagnetic loss provides a feasible and universal strategy to design high-performance electromagnetic attenuation materials based on the ferroelectric family.
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Tyrosinase is a copper-containing oxidation enzyme, which is responsible for the production of melanin. This enzyme is widely distributed in microorganisms, animals and plants, and plays an essential role in undesirable browning of fruits and vegetables, antibiotic resistance, skin pigment formation, sclerotization of cuticle, neurodegeneration, etc. Hence, it has been recognized as a therapeutic target for the development of antibrowning agents, antibacterial agents, skin-whitening agents, insecticides, and other therapeutic agents. With great potential application in food, agricultural, cosmetic and pharmaceutical industries, a large number of synthetic tyrosinase inhibitors have been widely reported in recent years. In this review, we systematically summarized the advances of synthetic tyrosinase inhibitors in the literatures, including their inhibitory activity, cytotoxicity, structure-activity relationship (SAR), inhibition kinetics, and interaction mechanisms with the enzyme. The collected information is expected to provide a rational guidance and effective strategy to develop novel, potent and safe tyrosinase inhibitors for better practical applications in the future.
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Inibidores Enzimáticos , Monofenol Mono-Oxigenase , Animais , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Cinética , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Relação Estrutura-AtividadeRESUMO
Microtubules play an important role in the process of cell mitosis and can form a spindle in the mitotic prophase of the cell, which can pull chromosomes to the ends of the cell and then divide into two daughter cells to complete the process of mitosis. Tubulin inhibitors suppress cell proliferation by inhibiting microtubule dynamics and disrupting microtubule homeostasis. Thereby inducing a cell cycle arrest at the G2/M phase and interfering with the mitotic process. It has been found that a variety of chalcone derivatives can bind to microtubule proteins and disrupt the dynamic balance of microtubules, inhibit the proliferation of tumour cells, and exert anti-tumour effects. Consequently, a great number of studies have been conducted on chalcone derivatives targeting microtubule proteins. In this review, synthetic or natural chalcone microtubule inhibitors in recent years are described, along with their structure-activity relationship (SAR) for anticancer activity.
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Antineoplásicos/farmacologia , Chalconas/farmacologia , Neoplasias/tratamento farmacológico , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Chalconas/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Moduladores de Tubulina/químicaRESUMO
A series of litseaone B analogues 4aâ¼4p were synthesised and antitumor activities of all compounds were screened. These compounds were designed by introducing different substituents on the B ring. Among these synthesised compounds, it was proved that 4k showed excellent activity against A549, HepG2, and HCT-15 cell lines, the IC50 values were 7.60 µM, 20.53 µM, and 4.59 µM, respectively. The results of tubulin polymerisation inhibition and immunofluorescence staining experiments displayed that 4k could act on tubulin and inhibit the polymerisation of tubulin. Moreover, the wound healing assay showed that 4k could inhibit the migration of A549 cells in a dose-dependent manner. Furthermore, the results of flow cytometry revealed that 4k was capable of blocking the cell cycle in the G2/M phase, inducing a decrease in the mitochondrial membrane potential and ultimately leading to apoptosis in A549 cells. Importantly, the possible binding model was also performed by molecular docking. Subject classification codes: short communication.
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Moduladores de Tubulina , Tubulina (Proteína) , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides , Simulação de Acoplamento Molecular , Tubulina (Proteína)/metabolismoRESUMO
Target search for moving and invisible objects has always been considered a challenge, as the floating objects drift with the flows. This study focuses on target search by multiple autonomous underwater vehicles (AUV) and investigates a multi-agent target search method (MATSMI) for moving and invisible objects. In the MATSMI algorithm, based on the multi-agent deep deterministic policy gradient (MADDPG) method, we add spatial and temporal information to the reinforcement learning state and set up specialized rewards in conjunction with a maritime target search scenario. Additionally, we construct a simulation environment to simulate a multi-AUV search for the floating object. The simulation results show that the MATSMI method has about 20% higher search success rate and about 70 steps shorter search time than the traditional search method. In addition, the MATSMI method converges faster than the MADDPG method. This paper provides a novel and effective method for solving the maritime target search problem.
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Algoritmos , Projetos de Pesquisa , Simulação por Computador , AprendizagemRESUMO
A novel series of thiazole-naphthalene derivatives as tubulin polymerisation inhibitors were designed, synthesised, and evaluated for the anti-proliferative activities. The majority of the tested compounds exhibited moderate to potent antiproliferative activity on the MCF-7 and A549 cancer cell lines. Among them, compound 5b was found to be the most active compound with IC50 values of 0.48 ± 0.03 and 0.97 ± 0.13 µM. Moreover, mechanistic studies revealed that 5b significantly inhibited tubulin polymerisation with an IC50 value of 3.3 µM, as compared to the standard drug colchicine (IC50 = 9.1 µM). Further cellular mechanism studies elucidated that 5b arrested the cell cycle at G2/M phase and induced apoptosis in MCF-7 cancer cells. Molecular modelling study indicated that 5b binds well to the colchicine binding site of tubulin. In summary, these results suggest that 5b represents a promising tubulin polymerisation inhibitor worthy of further investigation as potential anticancer agents.
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Antineoplásicos/farmacologia , Desenho de Fármacos , Naftalenos/farmacologia , Tiazóis/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Naftalenos/síntese química , Naftalenos/química , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/químicaRESUMO
A new series of sulphonamide derivatives bearing naphthalene moiety were synthesised and evaluated for their antiproliferative and tubulin polymerisation inhibitory activities. These new compounds were evaluated for their in vitro antiproliferative activity against MCF-7 and A549 by using CCK-8 method. Among all the tested compounds, compound 5c with naphthalen-1-yl moiety exhibited the most potent antiproliferative activity against MCF-7 and A549 cell line, with IC50 values of 0.51 ± 0.03 µM and 0.33 ± 0.01 µM, respectively. The results of tubulin polymerisation assay shown that 5c exhibited a significant ability to inhibit tubulin polymerisation with IC50 value of 2.8 µM. Consistent with its antitubulin activity, 5c can significantly arrest the cell cycle at G2/M phase and induce apoptosis in MCF-7 cancer cells. Molecular docking study indicated that compound 5c inhibited tubulin polymerisation through interacting at the colchicine-binding site of tubulin. Furthermore, 5c exhibited low cytotoxic activity on human normal cell line.
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Antineoplásicos/farmacologia , Naftalenos/química , Sulfonamidas/farmacologia , Moduladores de Tubulina/farmacologia , Células A549 , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade , Sulfonamidas/química , Moduladores de Tubulina/químicaRESUMO
Two new benzo[de]isoquinoline derivatives, 4-phenyl-benzo[de]isoquinoline-1,3-dione (1) and 4-(4-hydroxyphenyl)-benzo[de]isoquinoline-1,3-dione (2), were isolated from 70% ethanol extract of the rhizomes of Musa basjoo. Their chemical structures were elucidated by HRESIMS, 1 D and 2 D spectra.