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1.
Proc Natl Acad Sci U S A ; 119(45): e2208505119, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322772

RESUMO

The linear positive magnetoresistance (LPMR) is a widely observed phenomenon in topological materials, which is promising for potential applications on topological spintronics. However, its mechanism remains ambiguous yet, and the effect is thus uncontrollable. Here, we report a quantitative scaling model that correlates the LPMR with the Berry curvature, based on a ferromagnetic Weyl semimetal CoS2 that bears the largest LPMR of over 500% at 2 K and 9 T, among known magnetic topological semimetals. In this system, masses of Weyl nodes existing near the Fermi level, revealed by theoretical calculations, serve as Berry-curvature monopoles and low-effective-mass carriers. Based on the Weyl picture, we propose a relation [Formula: see text], with B being the applied magnetic field and [Formula: see text] the average Berry curvature near the Fermi surface, and further introduce temperature factor to both MR/B slope (MR per unit field) and anomalous Hall conductivity, which establishes the connection between the model and experimental measurements. A clear picture of the linearly slowing down of carriers, i.e., the LPMR effect, is demonstrated under the cooperation of the k-space Berry curvature and real-space magnetic field. Our study not only provides experimental evidence of Berry curvature-induced LPMR but also promotes the common understanding and functional designing of the large Berry-curvature MR in topological Dirac/Weyl systems for magnetic sensing or information storage.

2.
Anal Chem ; 96(3): 1301-1309, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38193144

RESUMO

Microalgae play a crucial role in global carbon cycling as they convert carbon dioxide into various valuable macromolecules. Among them, Haematococcus pluvialis (H. pluvialis) is the richest natural source of astaxanthin (AXT), which is a valuable antioxidant, anti-inflammatory, and antiapoptosis agent. These benefits make AXT highly commercially valuable in pharmaceuticals, cosmetics, and nutritional industries. However, intrinsic genetic characteristics and extrinsic cultivation conditions influence biomass gains, leading to low productivity and extraction as the main techno-economic bottlenecks in this industry. Thus, detecting AXT in H. pluvialis is essential to determine the influence of multiple parameters on biocompound accumulation, enabling optimization of cultivation and enrichment of AXT-rich H. pluvialis cells. This work developed an opto-acousto-fluidic microplatform for detection, analysis, and sorting of microalgae. Via label-free monitoring and extraction of sample-induced ultrasonic signals, a photoacoustic microscopic system was proposed to provide a full-field visualization of AXT's content and distribution inside H. pluvialis cells. When employed as on-chip image-based flow cytometry, our microplatform can also offer high-throughput measurements of intracellular AXT in real time, which demonstrates similar results to conventional spectrophotometry methods and further reveals the heterogeneity of AXT content at the single-cell level. In addition, a solenoid valve-pump dual-mode cell sorter was integrated for effective sorting of cells with a maximum working frequency of 0.77 Hz, reducing the fluid response time by 50% in rising and 40-fold in recovery. The H. pluvialis cells which have more AXT accumulation (>30 µm in diameter) were 4.38-fold enriched with almost no dead empty and small green cells. According to the results, automated and reliable photoacoustics-activated cell sorting (PA-ACS) can screen AXT-rich cells and remove impurities at the terminal stage of cultivation, thereby increasing the effectiveness and purity of AXT extraction. The proposed system can be further adopted to enrich strains and mutants for the production of biofuels or other rare organic substances such as ß-carotene and lutein.


Assuntos
Clorofíceas , Microalgas , Luteína , Análise Espectral , Movimento Celular
3.
Nano Lett ; 23(14): 6449-6457, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37379096

RESUMO

Spin obit torque (SOT) driven magnetization switching has been used widely for encoding consumption-efficient memory and logic. However, symmetry breaking under a magnetic field is required to realize the deterministic switching in synthetic antiferromagnets with perpendicular magnetic anisotropy (PMA), which limits their potential applications. Herein, we report all electric-controlled magnetization switching in the antiferromagnetic Co/Ir/Co trilayers with vertical magnetic imbalance. Besides, the switching polarity could be reversed by optimizing the Ir thickness. By using the polarized neutron reflection (PNR) measurements, the canted noncollinear spin configuration was observed in Co/Ir/Co trilayers, which results from the competition of magnetic inhomogeneity. In addition, the asymmetric domain walls demonstrated by micromagnetic simulations result from introducing imbalance magnetism, leading to the deterministic magnetization switching in Co/Ir/Co trilayers. Our findings highlight a promising route to electric-controlled magnetism via tunable spin configuration, improve our understanding of physical mechanisms, and significantly promote industrial applications in spintronic devices.

4.
J Cell Mol Med ; 27(20): 3065-3074, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37487001

RESUMO

The migratory ability of microglia facilitates their rapid transport to a site of injury to kill and remove pathogens. However, the effect of Treponema pallidum membrane proteins on microglia migration remains unclear. The effect of Tp47 on the migration ability and autophagy and related mechanisms were investigated using the human microglial clone 3 cell line. Tp47 inhibited microglia migration, the expression of autophagy-associated protein P62 decreased, the expression of Beclin-1 and LC3-II/LC3-I increased, and the autophagic flux increased in this process. Furthermore, autophagy was significantly inhibited, and microglial cell migration was significantly increased after neutralisation with an anti-Tp47 antibody. In addition, Tp47 significantly inhibited the expression of p-PI3K, p-AKT, and p-mTOR proteins, and the sequential activation of steps in the PI3K/AKT/mTOR pathways effectively prevented Tp47-induced autophagy. Moreover, Tp47 significantly inhibited the expression of p-FOXO1 protein and promoted FOXO1 nuclear translocation. Inhibition of FOXO1 effectively suppressed Tp47-induced activation of autophagy and inhibition of migration. Treponema pallidum membrane protein Tp47-induced autophagy and inhibited cell migration in HMC3 Cells via the PI3K/AKT/FOXO1 pathway. These data will contribute to understanding the mechanism by which T. pallidum escapes immune killing and clearance after invasion into the central nervous system.

5.
Small ; 19(38): e2300122, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37144423

RESUMO

As a clean and effective approach, the introduction of external magnetic fields to improve the performance of catalysts has attracted extensive attention. Owing to its room-temperature ferromagnetism, chemical stability, and earth abundance, VSe2 is expected to be a promising and cost-effective ferromagnetic electrocatalyst for the accomplishment of high-efficient spin-related OER kinetics. In this work, a facile pulsed laser deposition (PLD) method combined with rapid thermal annealing (RTA) treatment is used to successfully confine monodispersed 1T-VSe2 nanoparticles in amorphous carbon matrix. As expected, with external magnetic fields of 800 mT stimulation, the confined 1T-VSe2 nanoparticles exhibit highly efficient oxygen evolution reaction (OER) catalytic activity with an overpotential of 228 mV for 10 mA cm-2 and remarkable durability without deactivation after >100 h OER operation. The experimental results together with theoretical calculations illustrate that magnetic fields can facilitate the surface charge transfer dynamics of 1T-VSe2 , and modify the adsorption-free energy of *OOH, thus finally improving the intrinsic activity of the catalysts. This work realizes the application of ferromagnetic VSe2 electrocatalyst in highly efficient spin-dependent OER kinetics, which is expected to promote the application of transition metal chalcogenides (TMCs) in external magnetic field-assisted electrocatalysis.

6.
J Med Virol ; 95(4): e28703, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36965144

RESUMO

Given the prevalence of low-pathogenic but highly infectious Omicron variants, a cohort study was conducted to assess the response and duration of novel coronavirus-inactivated vaccine-induced antibodies 1 year after the third dose (Day 641). Blood samples were collected and anti-spike neutralizing antibodies (neutralizing antibody), total antibodies against the receptor-binding domain of the spike protein (total antibody), and immunoglobulin G antibodies against the spike protein (IgG antibody) were determined. Antibody kinetics and attenuation were evaluated. The results showed that the levels of neutralizing, total, and IgG antibodies on Day 641 were 98.05 IU/mL, 152.8 AU/mL, and 7.68 S/CO, respectively. Levels of anti-SARS-CoV-2 antibodies were higher in the younger subgroup than in the older subgroup at several time points after the second and third doses. The seropositive rate of neutralizing antibodies providing protection from infection or severe infection was 46.87% and 87.5%, and the seropositive rates of total antibody and IgG antibody were maintained at 100% and 90.63%, respectively. The half-lives of neutralizing, total, and IgG antibodies were 186.89, 363.04, and 417.50 days, respectively. Collectively, anti-SARS-CoV-2 antibodies may provide a certain degree of protection from infection 1 year after the third dose and high protection from severe infection.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Estudos Prospectivos , Estudos de Coortes , Estudos Longitudinais , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunoglobulina G
7.
Chaos Solitons Fractals ; 167: 112996, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36589549

RESUMO

COVID-19 is the most serious public health event of the 21st century and has had a huge impact across the world. The spatio-temporal pattern analysis and simulation of epidemic spread have become the focus of current research. LSTM model has made a lot of achievements in the prediction of infectious diseases by virtue of its advantages in time prediction, but lacks the spatial expression. CA model plays an important role in epidemic spatial propagation modeling due to its unique evolution characteristics from local to global. However, no existing studies of CA have considered long-term dependence due to the impact of time changes on the evolution of the epidemic, and few have modeled using location data from actual diagnosed patients. Therefore, we proposed a LSTM-CA model to solve above mentioned problems. Base on the advantages of LSTM in temporal level and CA in spatial level, LSTM and CA are integrated from the spatio-temporal perspective of geography based on the fine-grained characteristics of epidemic data. The method divides the study area into regular grids, simulates the spatial interactions between neighborhood cells with the help of CA model, and extracts the parameters affecting the transition probability in CA with the help of LSTM model to assist evolution. Simulations are conducted in Python 3.4 to model the propagation of COVID-19 between Feb, 6 to Mar 20, 2020 in China. Experimental results show that, LSTM-CA performs a higher statistical accuracy than LSTM and spatial accuracy than CA, which could demonstrate the effectiveness of the proposed model. This method could be universal for the temporal and spatial transmission of major public health events. Especially in the early stage of the epidemic, we can quickly understand its development trend and cycle, so as to provide an important reference for epidemic prevention and control and public sentiment counseling.

8.
Environ Dev Sustain ; : 1-19, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-37363032

RESUMO

Food security and the utilization of natural resources in a sustainable manner are vital to the expansion of China's agricultural system. The relationship between environmental pressure and dietary structure has influenced the quantity and spatial distribution of China's food supply and demand, but it has not been evaluated. Our research centered on the security of China's food nutrition-resources-food (NRF) system, considering the inherent relationship between food security, nutritional health, and resource security. The following are the study's findings: (1) The Chinese population is rapidly changing from a diet focused on grains to a more diverse diet. Between 1990 and 2019, the dietary quality and nutritional status of Chinese individuals have vastly improved. In terms of nutrient levels, discrepancies between urban and rural resident persist, with urban residents consuming a diet that is closer to the ideal structure. However, the structure of rural residents' food consumption is diversifying, and the gap between urban and rural residents is gradually narrowing. (2) From 2000 to 2019, the pressure, status, and response indices of China's NRF system all show an upward trend, and the security of the NRF system has steadily grown. The magnitude of change in the response index exceeded that of the state index, which exceeded that of the pressure index. This indicates that the increase in the pressure and state indices of the NRF system was primarily attributable to the effectiveness of policy efforts.

9.
Anal Chem ; 94(15): 5769-5775, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35384647

RESUMO

In order to obtain high yield of astaxanthin, a high-value compound with ultrastrong antioxidant capacity, it is necessary to identify the growth characteristics (biomass, morphology, and size) of Haematococcus pluvialis. The current detection methods have the disadvantages of labor-consuming operation or complicated measurement system. It is an urgent need to explore a simple and cost-effective method for the detection of H. pluvialis with large size distribution during its growth period. In this work, a digital in-line holographic flow cytometry using a linear array sensor is proposed to measure the growth characteristics of H. pluvialis in a two-dimensional (2-D) hydrodynamic focusing microfluidic chip. Based on the modified angular spectrum method, the distorting holograms caused by the asynchrony of sample flow velocity and acquisition speed of the linear array sensor were rectified and reconstructed. In addition, the depth-of-focus of the imaging system were digitally extended to cover the entire depth of the microfluidic channel for optimized imaging quality. We have utilized the proposed method to statistically investigate the biomass, morphology and size of H. pluvialis under different culture conditions and growth durations.


Assuntos
Clorofíceas , Microfluídica , Antioxidantes , Biomassa , Citometria de Fluxo
10.
Inorg Chem ; 61(46): 18380-18389, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36346941

RESUMO

Studying ultrafast dynamics provides us with a way to modify materials from the timescale of particle interaction, and the related research on antiferromagnetic semiconductors is still inadequate. Based on the electron density reconstruction, we achieve the visualization of magnetic interactions of bulk antiferromagnetic MnPS3 in the ground state, reveal the role of two atomic site occupations of S atoms in different magnetic phase transitions, and provide the theoretical and experimental support for modifying magnetic properties by selectively replacing the S atom. The ultrafast carrier dynamics can provide information from the excited state to the ground state. Based on time-resolved transmittance measurements, ultrafast carrier dynamics of MnPS3 are reported. The phonon-assisted gap transition driven by the electronic structure is characterized. The coupling relationship among electrons, spin, and phonons is established. Furthermore, the spin orientations within different phases are confirmed.

11.
Pharm Biol ; 60(1): 144-153, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34962431

RESUMO

CONTEXT: Suchilactone, a lignan compound extracted from Monsonia angustifolia E.Mey. ex A.Rich. (Geraniaceae), has little research on pharmacological activity; whether suchilactone has inhibitory effect on acute myeloid leukaemia (AML) is unclear. OBJECTIVE: To investigate the antitumor effect of suchilactone and its mechanism in AML. MATERIALS AND METHODS: The effects of suchilactone on cell growth were detected by CCK-8 and flow cytometry. Network pharmacology was conducted to explore target of suchilactone. Gene expression was detected by western blot and RT-PCR. SHI-1 cells (1 × 106 cell per mouse) were subcutaneously inoculated into the female SCID mice. Suchilactone (15 and 30 mg/kg) was dissolved in PBS with 0.5% carboxymethylcellulose sodium and administered (i.g.) to mice once a day for 19 days, while the control group received PBS with 0.5% carboxymethylcellulose sodium. Tumour tissues were stained with Ki-67 and TUNEL. RESULTS: Suchilactone exerted an effective inhibition on the growth of SHI-1 cells with IC50 of 17.01 µM. Then, we found that suchilactone binds to the SHP2 protein and inhibits its activation, and suchilactone interacted with SHP2 to inhibit cell proliferation and promote cell apoptosis via blocking the activation of SHP2. Moreover, Suchilaction inhibited tumour growth of AML xenografts in mice, as the tumour weight decreased from 0.618 g (control) to 0.35 g (15 mg/kg) and 0.258 g (30 mg/kg). Suchilactone inhibited Ki-67 expression and increased TUNEL expression in tumour tissue. DISCUSSION AND CONCLUSIONS: Our study is the first to demonstrate suchilactone inhibits AML growth, suggesting that suchilactone is a candidate drug for the treatment of AML.


Assuntos
Antineoplásicos Fitogênicos , Geraniaceae , Leucemia Mieloide Aguda , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Animais , Feminino , Humanos , Camundongos , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Geraniaceae/química , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos Endogâmicos BALB C , Camundongos SCID , Farmacologia em Rede , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Inorg Chem ; 59(12): 8603-8608, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32462872

RESUMO

A large linear negative thermal expansion (NTE) and expanded NTE temperature range (ΔTNTE) were obtained in magnetoelastic CrTe1-xSex (0 ≤ x ≤ 0.15) compounds. For CrTe compound, its thermal expansion coefficient of volume (αV) was calculated to be -28.8 ppm K-1 with the temperature ranging from 280 to 340 K. Substituting Te with Se atoms, the NTE behavior and magnetic properties can be well manipulated. With increasing Se in CrTe1-xSex (0 ≤ x ≤ 0.15) compounds, the ΔTNTE increases from 60 K (280-340 K for x = 0), to 80 K (240-320 K for x = 0.05), to 95 K (200-295 K for x = 0.1), and finally to 100 K (170-270 K for x = 0.15). Furthermore, a linear NTE remains independent of temperature for samples with x ≤ 0.1. The relationship between tunable NTE and magnetic properties was analyzed in detail, indicating that the NTE in CrTe1-xSex compounds originates from the magnetovolume effect (MVE).

13.
Chaos Solitons Fractals ; 140: 110214, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32839643

RESUMO

The COVID-19 outbreak in late December 2019 is still spreading rapidly in many countries and regions around the world. It is thus urgent to predict the development and spread of the epidemic. In this paper, we have developed a forecasting model of COVID-19 by using a deep learning method with rolling update mechanism based on the epidemical data provided by Johns Hopkins University. First, as traditional epidemical models use the accumulative confirmed cases for training, it can only predict a rising trend of the epidemic and cannot predict when the epidemic will decline or end, an improved model is built based on long short-term memory (LSTM) with daily confirmed cases training set. Second, considering the existing forecasting model based on LSTM can only predict the epidemic trend within the next 30 days accurately, the rolling update mechanism is embedded with LSTM for long-term projections. Third, by introducing Diffusion Index (DI), the effectiveness of preventive measures like social isolation and lockdown on the spread of COVID-19 is analyzed in our novel research. The trends of the epidemic in 150 days ahead are modeled for Russia, Peru and Iran, three countries on different continents. Under our estimation, the current epidemic in Peru is predicted to continue until November 2020. The number of positive cases per day in Iran is expected to fall below 1000 by mid-November, with a gradual downward trend expected after several smaller peaks from July to September, while there will still be more than 2000 increase by early December in Russia. Moreover, our study highlights the importance of preventive measures which have been taken by the government, which shows that the strict controlment can significantly reduce the spread of COVID-19.

14.
Chaos Solitons Fractals ; 139: 110058, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32834611

RESUMO

COVID-19 has now had a huge impact in the world, and more than 8 million people in more than 100 countries are infected. To contain its spread, a number of countries published control measures. However, it's not known when the epidemic will end in global and various countries. Predicting the trend of COVID-19 is an extremely important challenge. We integrate the most updated COVID-19 epidemiological data before June 16, 2020 into the Logistic model to fit the cap of epidemic trend, and then feed the cap value into FbProphet model, a machine learning based time series prediction model to derive the epidemic curve and predict the trend of the epidemic. Three significant points are summarized from our modeling results for global, Brazil, Russia, India, Peru and Indonesia. Under mathematical estimation, the global outbreak will peak in late October, with an estimated 14.12 million people infected cumulatively.

15.
Chaos Solitons Fractals ; 140: 110123, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834635

RESUMO

COVID-19 blocked Wuhan in China, which was sealed off on Chinese New Year's Eve. During this period, the research on the relevant topics of COVID-19 and emotional expressions published on social media can provide decision support for the management and control of large-scale public health events. The research assisted the analysis of microblog text topics with the help of the LDA model, and obtained 8 topics ("origin", "host", "organization", "quarantine measures", "role models", "education", "economic", "rumor") and 28 interactive topics. Obtain data through crawler tools, with the help of big data technology, social media topics and emotional change characteristics are analyzed from spatiotemporal perspectives. The results show that: (1) "Double peaks" feature appears in the epidemic topic search curve. Weibo on the topic of the epidemic gradually reduced after January 24. However, the proportion of epidemic topic searches has gradually increased, and a "double peaks" phenomenon appeared within a week; (2) The topic changes with time and the fluctuation of the topic discussion rate gradually weakens. The number of texts on different topics and interactive topics changes with time. At the same time, the discussion rate of epidemic topics gradually weakens; (3) The political and economic center is an area where social media is highly concerned. The areas formed by Beijing, Shanghai, Guangdong, Sichuan and Hubei have published more microblog texts. The spatial division of the number of Weibo social media texts has a high correlation with the economic zone division; (4) The existence of the topic of "rumor" will enable people to have more communication and discussion. The interactive topics of "rumors" always have higher topic popularity and low emotion text expressions. Through the analysis of media information, it helps relevant decision makers to grasp social media topics from spatiotemporal characteristics, so that relevant departments can accurately grasp the public's subjective ideas and emotional expressions, and provide decision support for macro-control response strategies and measures and risk communication.

16.
J Am Chem Soc ; 137(5): 1746-9, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25629796

RESUMO

MnCoGe-based compounds undergo a giant negative thermal expansion (NTE) during the martensitic structural transition from Ni2In-type hexagonal to TiNiSi-type orthorhombic structure. High-resolution neutron diffraction experiments revealed that the expansion of unit cell volume can be as large as ΔV/V ∼ 3.9%. The optimized compositions with concurrent magnetic and structural transitions have been studied for magnetocaloric effect. However, these materials have not been considered as NTE materials partially due to the limited temperature window of phase transition. The as-prepared MnCoGe-based compounds are quite brittle and naturally collapse into powders. By using a few percents (3-4%) of epoxy to bond the powders, we introduced residual stress in the bonded samples and thus realized the broadening of structural transition by utilizing the specific characteristics of lattice softening enforced by the stress. As a result, giant NTE (not only the linear NTE coefficient α but also the operation-temperature window) has been achieved. For example, the average α̅ as much as -51.5 × 10(-6)/K with an operating temperature window as wide as 210 K from 122 to 332 K has been observed in a bonded MnCo0.98Cr0.02Ge compound. Moreover, in the region between 250 and 305 K near room temperature, the α value (-119 × 10(-6)/K) remains nearly independent of temperature. Such an excellent performance exceeds that of most other materials reported previously, suggesting it can potentially be used as a NTE material, particularly for compensating the materials with large positive thermal expansions.

17.
Sci Rep ; 14(1): 721, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184685

RESUMO

The Catering Service Industry (CSI) experienced profound impacts due to the COVID-19 pandemic. However, the long-term and multi-timepoint analysis using big data remained limited, influencing governmental decision-making. We applied Kernel Density Estimation, Shannon Diversity Index, and the Geographic detector to explore the spatial heterogeneity and determinants of the CSI in Beijing during the pandemic, with monthly granularity. The temporal-spatial dynamics of the CSI presented a "W"-shaped trend from 2018 to 2023, with pivotal shifts aligning with key pandemic stages. Spatial characteristics exhibited heterogeneity, with greater stability in the city center and more pronounced shifts in peripheral urban zones. Districts facing intricate outbreaks showed lower catering income, and Chinese eateries exhibited heightened resilience compared to others. The CSI displayed strong interconnections with living service sectors. Development in each district was influenced by economic level, population distribution, service facilities convenience, and the risk of the COVID-19 pandemic. Dominant factors included total retail sales of consumer goods, permanent population, average Baidu Heat Index, density of transportation and catering service facilities, infection cases and the consecutive days with confirmed cases existing. Consequently, we suggested seizing post-pandemic recovery as an avenue to unlock the CSI's substantial potential, ushering a fresh phase of growth.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Big Data , Pandemias , Pequim , Indústrias
18.
Int Immunopharmacol ; 126: 111204, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38016343

RESUMO

Glycolysis is a key pathway in cellular glucose metabolism for energy supply and regulates immune cell activation. Whether glycolysis is involved in the activation of NOD-like receptor family protein 3 (NLRP3) inflammasomes during Treponema pallidum (T. pallidum) infection is unclear. In this study, the effect of T. pallidum membrane protein Tp47 on NLRP3 inflammasome activation in rabbit peritoneal macrophages was analysed and the role of glycolysis in NLRP3 inflammasome activation was explored. The results showed that Tp47 promoted NLRP3, caspase-1, and IL-1ß mRNA expression in macrophages, enhanced glycolysis and glycolytic capacity of macrophage, and promoted the production of macrophage glycolytic metabolites citrate, phosphoenolpyruvate, and lactate. The M2 pyruvate kinase (PKM2) inhibitor shikonin down-regulated the Tp47-promoted NLRP3, caspase-1, and IL-1ß mRNA expression in macrophages, and suppressed the Tp47-enhanced glycolysis and glycolytic capacity. Similarly, si-PKM2 significantly inhibited Tp47-promoted NLRP3, caspase-1, and IL-1ß mRNA expression and the Tp47-enhanced glycolysis and glycolytic capacity in macrophages. In conclusion, Tp47 activated NLRP3 inflammasomes via PKM2-dependent glycolysis and provided a new perspective on the effect of T. pallidum infection on host macrophages, which would contribute to the understanding of the infection mechanism and host immune mechanism of T. pallidum.


Assuntos
Inflamassomos , Treponema pallidum , Animais , Coelhos , Inflamassomos/metabolismo , Treponema pallidum/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR/metabolismo , Macrófagos , Proteínas Recombinantes/farmacologia , Caspase 1/metabolismo , RNA Mensageiro/metabolismo , Glicólise , Interleucina-1beta/metabolismo
19.
Virulence ; 15(1): 2350892, 2024 12.
Artigo em Inglês | MEDLINE | ID: mdl-38745370

RESUMO

The evasive tactics of Treponema pallidum pose a major challenge in combating and eradicating syphilis. Natural killer (NK) cells mediate important effector functions in the control of pathogenic infection, preferentially eliminating targets with low or no expression of major histocompatibility complex (MHC) class I. To clarify T. pallidum's mechanisms in evading NK-mediated immunosurveillance, experiments were performed to explore the cross-talk relations among T. pallidum, NK cells, and platelets. T. pallidum adhered to, activated, and promoted particle secretion of platelets. After preincubation with T. pallidum, platelets expressed and secreted high levels of MHC class I, subsequently transferring them to the surface of T. pallidum, potentially inducing an immune phenotype characterized by the "pseudo-expression" of MHC class I on the surface of T. pallidum (hereafter referred to a "pseudo-expression" of MHC class I). The polA mRNA assay showed that platelet-preincubated T. pallidum group exhibited a significantly higher copy number of polA transcript than the T. pallidum group. The survival rate of T. pallidum mirrored that of polA mRNA, indicating that preincubation of T. pallidum with platelets attenuated NK cell lethality. Platelets pseudo-expressed the MHC class I ligand on the T. pallidum surface, facilitating binding to killer cell immunoglobulin-like receptors with two immunoglobulin domains and long cytoplasmic tail 3 (KIR2DL3) on NK cells and initiating dephosphorylation of Vav1 and phosphorylation of Crk, ultimately attenuating NK cell lethality. Our findings elucidate the mechanism by which platelets transfer MHC class I to the T. pallidum surface to evade NK cell immune clearance.


Assuntos
Plaquetas , Antígenos de Histocompatibilidade Classe I , Células Matadoras Naturais , Sífilis , Treponema pallidum , Células Matadoras Naturais/imunologia , Treponema pallidum/imunologia , Treponema pallidum/genética , Humanos , Plaquetas/imunologia , Plaquetas/microbiologia , Antígenos de Histocompatibilidade Classe I/imunologia , Sífilis/imunologia , Sífilis/microbiologia , Evasão da Resposta Imune
20.
Sci Rep ; 13(1): 2913, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36805527

RESUMO

The urban development of China is changing from incremental expansion to stock renewal mode. The study of urban functional areas has become one of the important fundamental works in current urban renewal and high-quality urban development. In recent years, big spatiotemporal data has been well applied in the urban function field. However, the study of spatial-temporal evolution characteristics and forecasting optimization for mixed-use urban functional areas has not been examined well. Thus, in this study, we proposed a new approach that applies a revised information entropy method to analyze the degrees of mixing for urban functional areas. We applied our approach in Jinan City, Shandong Province as the study area. We used Point-of-Interest, OpenStreetMap and other datasets to identify the mixed-use urban functional areas in Jinan. Then, the CA-Markov model simulated the urban layout in 2025. The results showed that: (1) the combination of road network and kernel density method has the highest accuracy of identifying urban functional areas. (2)The mixing degree model is constructed by using the improved information entropy, which makes up for the shortcoming of identifying the mixed functional areas simply by the frequency ratio of POI data. (3) The "residence and business" functional area has the highest proportion in the central area of Jinan from 2015 to 2020, and the total area of mixed-use unban functional areas continuously increased during this period. (4) The total area of the central area in Jinan has significantly increased in 2025. The optimization of urban functions should expand mixed-use functional areas and increase the proportion of infrastructure. Also, Jinan should improve the efficiency of space development.

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