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1.
PLoS One ; 19(6): e0304207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38917092

RESUMO

Simultaneous acquisition is a construction method that has been proposed in recent years to meet the requirements of ultra-large-scale and high-precision seismic exploration. Such method is highly efficient and can significantly reduce exploration costs by saving manpower and material resources, being extensively used in offshore exploration and several foreign seismic exploration projects. The data deblending step is a significant part of the operation of simultaneous acquisition, which directly affects the acquired data quality, and is a key factor for the success of oil and gas exploration. The simultaneous use of multiple seismic sources can generate blended noise with a random distribution in non-shot-gather datasets. However, the useful signal exhibits strong coherence, making it possible to separate the non-used wavefield from the blended data. Although the blended noise is randomly distributed in non-shot-gather datasets, it also has characteristics that are different from normal ambient noise, and its kinematic and dynamical characteristics are almost similar to the useful signal. As such, traditional filtering methods are not applicable, especially in the case of strong background noise. In the present study, simultaneous acquisition was introduced, the principle of data deblending using CNN was analyzed, and a data deblending method based on an improved version of GoogLeNet was established. The experimental results show that the trained network model could quickly and effectively separate the mixed wavefield from blended data, and achieve the expected useful signal.


Assuntos
Redes Neurais de Computação , Algoritmos
2.
China CDC Wkly ; 6(4): 69-74, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38313817

RESUMO

Introduction: Plague is a zoonotic disease that occurs naturally in specific geographic areas. Climate change can influence the populations of the plague host or vector, leading to variations in the occurrence and epidemiology of plague in animals. Methods: In this study, we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau. The data spanned from 2000 to 2022. We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson's correlation. Results: During the period from 2000 to 2022, the isolation rates of Yersinia pestis (Y.pestis) from marmots and fleas were 9.27% (451/4,864) and 7.17% (118/1,646), respectively. Additionally, we observed a positive rate of F1 antibody of 11.25% (443/3,937) in marmots and 18.16% (142/782) in dogs. With regards to climate, there was little variation, and a decreasing trend in blowing-sand days was observed. The temperature in the previous year showed a negative correlation with the Y. pestis isolation rate in marmots (r=-0.555, P=0.011) and the positive rate of F1 antibody in marmots (r=-0.552, P=0.012) in the current year. The average annual precipitation in the previous two years showed a positive correlation with marmot density (r=0.514, P=0.024), while blowing-sand days showed a negative correlation with marmot density (r=-0.701, P=0.001). Furthermore, the average annual precipitation in the previous three years showed a positive correlation with the isolation rate of Y. pestis from marmots (r=0.666, P=0.003), and blowing-sand days showed a negative correlation with marmot density (r=-0.597, P=0.009). Conclusions: The findings of this study indicate that there is a hysteresis effect of climate change on the prevalence of plague. Therefore, monitoring climate conditions can offer significant insights for implementing timely preventive and control measures to combat plague epidemics.

3.
Sci Rep ; 13(1): 17082, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816792

RESUMO

Urban commercial centres are the most concentrated areas of economic activity. Understanding the spatial distribution pattern and comprehensive strength of urban commercial centres is important to guide the reasonable graded allocation of urban commercial space, spatial structure optimization and sustainable development of the commercial economy. Herein, mobile phone signalling data are used to identify the functional connection between recreational and residential places and local spatial autocorrelation analysis is used to identify the 24 commercial centres in the central city of Hefei. The comprehensive strength evaluation system of commercial centres is constructed from their basic conditions and customer consumption behaviours, and their comprehensive strength indices are accordingly measured and graded. The spatial distribution characteristics of commercial centres at all levels are analysed, and optimisation suggestions are made for the whole area and region. The following conclusions are drawn from the results of this study. (1) Compared to traditional single-perspective evaluations, the developed comprehensive strength evaluation system considers supply and demand perspectives for commercial centres, providing a more holistic and accurate portrayal of the strengths of various centres within a region. (2) The current commercial centres are characterised by 'large dispersion and small concentration' in spatial and hierarchical distribution. (3) The commercial centres in Hefei have formed a relatively complete 'first, second, and third level' commercial centre system, with the first level as the core and relying on the urban road system to form a network spatial connection. (4) Most of the commercial centres are concentrated in the First Ring Road, Swan Lake in the Government Affairs District and Binhu Century Town Estate, while most areas north of the Second Ring Road and Binhu New District still lack large-scale commercial centres. This study provides a technical reference for analysing urban commercial spatial structure patterns and provides decision support for optimising the spatial layout of urban commercial service functions.

4.
Tohoku J Exp Med ; 260(3): 205-214, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37019647

RESUMO

Glioblastoma (GBM) is a highly aggressive primary brain tumor that shows intratumoral heterogeneity at the cellular and molecular level. Activation of programmed death receptor 1 (PD-1) interaction with its ligand PD-L1 is a well-known mechanism requisite for immune evasion deployed by malignant tumors including GBM. Herein, we set out to dissect the mechanism explaining the regulation of PD-L1 gene expression in GBM. The clinical samples consisted of 37 GBM tissues and 18 normal brain tissues. GBM cell model was treated by microRNA (miRNA) inhibitor, DNA constructs, and siRNAs. Assays of CCK-8 and Transwell insert were employed to assess the survival, migratory and invasive ability of GBM cell model. The immunosuppressive factor production, T cell apoptosis, and T cell cytotoxicity to GBM cells were evaluated in the co-culture system. GBM exhibited more miR-10b-5p abundance than normal at both tissue and cellular level. Suppression of miR-10b-5p weakened the ability of GBM cell model to survive, migrate, and invade, decreased the release of immunosuppressive factors, reduced T cell apoptosis, and strengthened the T cell cytotoxicity to GBM cell model. MiR-10b-5p conferred a negative control of Ten-eleven translocation 2 (TET2) that was downregulated in GBM. The functions of miR-10b-5p on GBM cell aggressiveness and immune evasion were mediated by TET2. TET2 recruited histone deacetylases HDAC1 and HDAC2 into the PD-L1 promoter region thus inhibiting its transcription. The study demonstrated the importance of miR-10b-5p-mediated repression of TET2 in PD-L1-driven immune evasion and their potential for immunotherapeutic targeting in GBM.


Assuntos
Dioxigenases , Glioblastoma , MicroRNAs , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Evasão da Resposta Imune , MicroRNAs/genética , MicroRNAs/metabolismo
5.
J Environ Sci (China) ; 128: 35-44, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36801040

RESUMO

Surface-enhanced Raman scattering (SERS) has been used in atmospheric aerosol detection as it enables the high-resolution analysis of particulate matter. However, its use in the detection of historical samples without damaging the sampling membrane while achieving effective transfer and the high-sensitivity analysis of particulate matter from sample films remains challenging. In this study, a new type of SERS tape was developed, consisting of Au nanoparticles (NPs) on an adhesive double-sided Cu film (DCu). The enhanced electromagnetic field generated by the coupled resonance of the local surface plasmon resonances of AuNPs and DCu led to an enhanced SERS signal with an experimental enhancement factor of 107. The AuNPs were semi-embedded and distributed on the substrate, and the viscous DCu layer was exposed, enabling particle transfer. The substrates exhibited good uniformity and favorable reproducibility with relative standard deviations of 13.53% and 9.74% respectively, and the substrates could be stored for 180 days with no signs of signal weakening. The application of the substrates was demonstrated by the extraction and detection of malachite green and ammonium salt particulate matter. The results demonstrated that SERS substrates based on AuNPs and DCu are highly promising in real-world environmental particle monitoring and detection.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Análise Espectral Raman/métodos , Ouro , Material Particulado , Reprodutibilidade dos Testes
6.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1001-1008, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285200

RESUMO

Ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF/MS) was used to investigate the effect of Pterocephalus hookeri on serum metabolism of adjuvant arthritis(AA) model rats induced by complete Freund's adjuvant. After the AA model was properly induced, the serum of rats was collected 30 days after treatment. UPLC-Q-TOF-MS chromatograms were collected and analyzed by principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). The results revealed that compared with the control group, the model group showed increased content of 12 biomarkers in the serum(P<0.05) and reduced content of the other nine biomarkers(P<0.05). P. hookeri extract could recover the above-mentioned 19 biomarkers to a certain range. Pathway enrichment showed that these markers mainly involved eight metabolic pathways, including valine, leucine, and isoleucine degradation, arachidonic acid metabolism, arginine and proline metabolism, glycerol phospholipid metabolism, primary bile acid biosynthesis, bile acid biosynthesis, tryptophan metabolism, and unsaturated fatty acid biosynthesis. The findings of this study demonstrate that P. hookeri extract can regulate metabolic disorders and promote the regression of metabolic phenotype to the normal level to exert the therapeutic effect on AA rats. This study is expected to provide a certain scientific basis for the biological research on the treatment of rheumatoid arthritis by P. hookeri.


Assuntos
Artrite Reumatoide , Medicamentos de Ervas Chinesas , Animais , Artrite Reumatoide/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Tibetana , Metabolômica , Ratos
7.
Front Pharmacol ; 12: 531325, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967742

RESUMO

Endotoxemia is characterized by initial uncontrollable inflammation, terminal immune paralysis, significant cell apoptosis and tissue injury, which can aggravate or induce multiple diseases and become one of the complications of many diseases. Therefore, anti-inflammatory and anti-apoptotic therapy is a valuable strategy for the treatment of endotoxemia-induced tissue injury. Traditional Chinese medicine exhibits great advantages in the treatment of endotoxemia. In this review, we have analyzed and summarized the active ingredients and their metabolites of Sanhuang Xiexin Decoction, a famous formula in endotoxemia therapy. We then have summarized the mechanisms of Sanhuang Xiexin Decoction against endotoxemia and its mediated tissue injury. Furthermore, silico strategy was used to evaluate the anti-apoptotic mechanism of anisodamine, a well-known natural product that widely used to improve survival in patients with septic shock. Finally, we also have summarized other anti-apoptotic natural products as well as their therapeutic effects on endotoxemia and its mediated tissue injury.

8.
RSC Adv ; 11(46): 28761-28774, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35478563

RESUMO

Pterocephalus hookeri (C. B. Clarke) Höeck is a member of the Dipsacaceae family and has been used in traditional Tibetan medicine for thousands of years. P. hookeri clears heat, detoxifies, stops dysentery, eliminates distemper, dispels wind, and relieves stagnation and is mainly prescribed for heat syndrome, dysentery, arthritis, and plague. Approximately 93 chemical compounds have been isolated and identified from P. hookeri, including iridoid glycosides, lignan and triterpenoids. Meanwhile, modern pharmacological studies have shown that P. hookeri has anti-inflammatory, anti-rheumatoid arthritis, analgesic, anticancer, and neuroprotection activities. However, studies on the in vivo pharmacokinetics and mechanism of action, discovery of quality markers, and qualitative and quantitative analysis are still insufficient. Hence, this paper provides a comprehensive review of the ethnic medicine, phytochemistry, pharmacology, and toxicology of P. hookeri to increase the understanding of the medicinal value of P. hookeri.

9.
Database (Oxford) ; 20192019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31738435

RESUMO

Since the invention over a hundred years ago, plastics have been used in many applications, and they are involved in every aspect of our lives. The extensive usage of plastics results in a tremendous amount of waste, which has become a severe burden on the environment. Several degradation approaches exist in nature to cope with ever-increasing plastic waste. Among these approaches, biodegradation by microorganisms has emerged as a natural way, which is favored by many environmentally conscious societies. To facilitate the study on biodegradation of plastics, we developed an online resource, Plastics Microbial Biodegradation Database (PMBD), to gather and present the information about microbial biodegradation of plastics. In this database, 949 microorganisms-plastics relationships and 79 genes involved in the biodegradation of plastics were manually collected and confirmed through literature searching. In addition, more than 8000 automatically annotated enzyme sequences, which were predicted to be involved in the plastics biodegradation, were extracted from the TrEMBL section of the UniProt database. The PMBD database is presented with a website at http://pmbd.genome-mining.cn/home. Data may be accessed through browsing or searching. Also included on the website are a sequence alignment tool and a function prediction tool.


Assuntos
Bases de Dados Factuais , Plásticos/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Alinhamento de Sequência
10.
J Colloid Interface Sci ; 553: 475-483, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31229866

RESUMO

To enhance hexavalent chromium (Cr(VI)) removal performance under acidic conditions, the nanofiltration (NF) membrane with enhanced negative charge was fabricated via introducing 2, 5-diaminobenzenesulfonic acid (DABSA) into polyamide layer. The control membrane (NF-P) was directly prepared from piperazine and 1, 3, 5-benzenetricarbonyltrichloride. Surface chemical compositions, morphology, surface charge, pore size, permeability and pH-dependent separation performance of the fabricated membranes were characterized. The membranes showed the similar water permeance (∼11.5 L m-2 h-1 bar-1) and Na2SO4 rejections (∼98%) under neutral environments. The DABSA introduced NF membrane (NF-PD) was negatively charged in the pH range of 2.5-11, while the isoelectric point for NF-P was ∼pH 4.0. Cr(VI) removal ability was then evaluated under various concentrations and pH environments. The results indicated that NF-PD showed the better Cr(VI) rejection performance in all tested conditions than NF-P, especially under acidic environments (e.g., pH 4 and pH 5). Moreover, there was a fluctuation of the rejection with the increase of Cr(VI) concentration under acidic environments, which was mainly caused by the formation of Cr2O72- species. The harmful Cr(VI) was efficiently removed by the NF membrane with enhanced negative charge under acidic environments, which indicated the wider application range of the NF membrane.

11.
World Neurosurg ; 84(2): 520-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25900791

RESUMO

OBJECTIVE: To explore the value of flat detector computed tomography-based vessel fusion technique for visualizing and evaluating anatomic structures and hemodynamic features of patients diagnosed with dural arteriovenous fistulas (DAVF). METHODS: Eleven patients with DAVF were investigated. The 3-dimensional structure of the DAVF fistula point, feeding arteries, and draining veins were reconstructed from separately acquired rotational angiographic images and then displayed as a single image in a fused manner. RESULTS: In the vessel fusion image, the tangled cluster of vessels of the DAVF could be clearly visualized from selected optimal viewing angles in the 3-dimensional space. Each component of the DAVF fistula point with its specific artery feedings and venous drainage could be identified accurately. CONCLUSIONS: The vessel fusion technique gave detailed anatomic information that enabled better understanding of the DAVF structure, and facilitated an accurate interventional or surgical planning.


Assuntos
Angiografia Digital/métodos , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Angiografia Cerebral/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Meios de Contraste , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia
12.
Int J Infect Dis ; 33: 67-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25555623

RESUMO

A case of primary pneumonic plague (PPP) caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case.


Assuntos
Marmota/microbiologia , Peste/diagnóstico , Adulto , Animais , China , Doenças do Cão/microbiologia , Cães , Humanos , Masculino , Peste/veterinária , Doenças dos Roedores/microbiologia , Yersinia pestis/isolamento & purificação
13.
J Neurointerv Surg ; 6(9): 667-71, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24235097

RESUMO

AIM: This study explored the value of using a vessel fusion technique for visualizing and evaluating the vessel structure of patients diagnosed with arteriovenous malformations (AVMs). MATERIALS AND: methods 10 patients with AVMs supplied by multiple cerebral arteries were investigated. The three-dimensional structure of the AVM nidus, feeding arteries, and draining veins were reconstructed from rotational angiographic images and then displayed on a single image in a fused manner. RESULTS: In the vessel fusion image, the tangled cluster of vessels surrounding the AVMs could be clearly visualized in three-dimensional space from a selected optimal viewing angle. Each AVM nidus component with its specific feeding arteries and venous drainage could be accurately identified. CONCLUSIONS: The vessel fusion technique offered detailed anatomical information that enabled clinicians to better understand the AVM structure, which helped with treatment planning.


Assuntos
Angiografia Digital/métodos , Angiografia Cerebral/métodos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/patologia , Processamento de Imagem Assistida por Computador/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/patologia , Adolescente , Adulto , Artéria Carótida Interna/patologia , Criança , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Artéria Vertebral/patologia , Adulto Jovem
14.
Opt Express ; 20(13): 13727-37, 2012 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-22714438

RESUMO

A conformal phosphor coating can realize a phosphor layer with uniform thickness, which could enhance the angular color uniformity (ACU) of light-emitting diode (LED) packaging. In this study, a novel freeform lens was designed for simultaneous realization of LED uniform illumination and conformal phosphor coating. The detailed algorithm of the design method, which involves an extended light source and double refractions, was presented. The packaging configuration of the LED modules and the modeling of the light-conversion process were also presented. Monte Carlo ray-tracing simulations were conducted to validate the design method by comparisons with a conventional freeform lens. It is demonstrated that for the LED module with the present freeform lens, the illumination uniformity and ACU was 0.89 and 0.9283, respectively. The present freeform lens can realize equivalent illumination uniformity, but the angular color uniformity can be enhanced by 282.3% when compared with the conventional freeform lens.


Assuntos
Lentes , Iluminação/instrumentação , Semicondutores , Desenho de Equipamento , Análise de Falha de Equipamento
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