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1.
Front Endocrinol (Lausanne) ; 13: 801925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35282434

RESUMO

Background: The prevalence of thyroid carcinoma (TC) and Hashimoto's thyroiditis (HT) has been increasing dramatically over the past decades. We investigated the relationship between HT and TC. Methods: We followed the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines for carrying out and reporting this meta-analysis. The literature from January 1, 2010 to December 31, 2020, regardless of region and publication type, was searched comprehensively in PubMed, Embase, Web of Science, and Cochrane Library databases. After careful selection and data extraction, the pooled odds ratio of various clinical characteristics in 39 studies were calculated. Publication bias was analyzed using funnel plots. Results: Meta-analysis of 39 original research articles showed HT to be a risk factor of TC (pooled odds ratio = 1.71; 95% confidence interval, 1.57-1.80; p < 0.00001) and papillary thyroid carcinoma (1.67, 1.51-1.85, <0.00001). Patients with papillary thyroid carcinoma (PTC) combined with HT were more likely to have multifocal carcinomas. The prevalence of an extrathyroidal extension, metastasis, BRAFV600E mutation, and recurrence was significantly lower in patients with PTC combined with HT. Conclusions: HT is a "double-edged sword" in TC patients. HT increases the risk of TC and PTC but is a protective factor against PTC progression.


Assuntos
Carcinoma , Doença de Hashimoto , Neoplasias da Glândula Tireoide , Carcinoma/patologia , Doença de Hashimoto/epidemiologia , Doença de Hashimoto/patologia , Humanos , Mutação , Estudos Observacionais como Assunto , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia
2.
Phytomedicine ; 100: 154055, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35344716

RESUMO

BACKGROUND: Dahuang Zhechong pill (DHZCP) improves the inhibitory immune status of mice with hepatocellular carcinoma (HCC) by regulating Treg/Th1 balance. HYPOTHESIS/PURPOSE: To study the multi-material basis and multi-mechanisms of DHZCP against HCC by regulating Treg/Th1 balance in vitro and in vivo. METHODS: UPLC-MS/MS was used to detect the dynamic changes in 29 characteristic components of different polar parts of DHZCP. H&E and TUNEL were used to check pathological condition in HCC mice. The number of CD4+T, CD8+T, Treg, Th1, and Th1-like Treg cells was counted by flow cytometry. TGF-ß, IL-10, IFN-γ, and TNF-α content were detected by ELISA. α-Ketoglutarate and glutamine levels were detected by Trace1310/TSQ8000 GC-MS/MS. p-Smad2, and p-Smad3 protein levels were detected by WB, mRNA expression of Smad2, alanine-serine-cysteine transporter-2, glutaminase, and glutamate dehydrogenase were detected by RT-PCR. Simca-p multivariate data analysis software was used to evaluate the relationship between the different polar parts of DHZCP and the proportion of Treg cells. RESULTS: Water-soluble (PW) and ethyl acetate (PE) polar parts of DHZCP affected the HCC immune system by inhibiting the differentiation of Tregs, reversing the balance of Treg/Th1, and significantly reduced the tumor volume and weight. However, petroleum ether and n-butanol polar parts had no above actions. The changes in emodin, chrysophanol, aloe vera emodin, emodin-8-O-ß-D-glycoside, gallic acid, naringenin, baicalein, wogonin, norwogonin, apigenin, chrysin, glycyrrhizin, formononetin, and palmitic acid were closely related to the changes of Treg cells, which is the main material basis of DHZCP inhibition of Treg differentiation. Additionally, PW mainly inhibit the differentiation of Treg cells by affecting the metabolism of hepatoma cells, improving tumor microenvironment acidity, and glutamine depletion. However, PE inhibited the differentiation of Treg cells mainly by regulating the TGF-ß/Smad pathway. CONCLUSION: In this study, accurate analysis of multi-component was combined with pharmacodynamic evaluations to identify the pharmacodynamic substances of DHZCP in regulating Treg/Th1 balance, and clarified the multi-target mechanism of DHZCP to improve tumor immunity. The study style offers a novel approach for pharmacological research on TCM.


Assuntos
Carcinoma Hepatocelular , Emodina , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Medicamentos de Ervas Chinesas , Glutamina , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Linfócitos T Reguladores , Espectrometria de Massas em Tandem , Fator de Crescimento Transformador beta , Microambiente Tumoral
3.
Front Oncol ; 12: 821958, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35280765

RESUMO

Background: Aldehyde dehydrogenase (ALDH) 1 is an important enzyme involved in the regulation of several cellular mechanisms via aldehyde detoxification. High ALDH1 levels were correlated with tumorigenesis and stemness maintenance in cancer. Methods: We used UALCAN, Human Protein Atlas, Kaplan-Meier plotter, TISIDB, TIMER, and KOBAS databases to investigate the expression and role of ALDH1 in thyroid cancer progression. In addition, quantitative real-time polymerase chain reaction was performed to detect the expression of the target genes in thyroid cancer cell lines and cancer tissues. Results: Expression of ALDH1A1/B1 was significantly decreased based on individual cancer stages and tumor histology, and high levels of ALDH1A1/B1 were associated with poor overall survival in thyroid cancer patients. Moreover, ALDH1A1/B1 expression was negatively correlated with immune-stimulating genes, major histocompatibility complex, chemokines, and receptors. Conclusions: These results suggest that ALDH1A1/B1 might serve as potential prognostic biomarkers for thyroid cancer diagnosis.

5.
Sci Total Environ ; 823: 153318, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121037

RESUMO

Water poverty is among the most significant global challenges and severely restricts the sustainable development of societies and economies, especially in the world's arid regions. Many countries have attempted to address this challenge. Market-based trading mechanisms represent an essential method of resolving the problem of water shortages and alleviating water poverty. Based on a quasi-natural experiment of water rights trading pilots in China, this study uses panel data from 31 provinces (municipalities) from 2009 to 2019 to explore the impact of water rights trading pilot policy on water poverty through a difference-in-differences (DID) model. The research results show that such policies can effectively alleviate water poverty by improving water-saving irrigation technology, promoting industrial and agricultural water trading, and optimizing the industrial structure. Additionally, dynamic effect and spatial heterogeneity analyses show that the water rights trading pilot policy have long-term effects and have a stronger mitigation effect on the western region of China compared with the central and eastern regions. Therefore, the Chinese government should not only further expand the implementation scope of these policies but also adjust measures according to local conditions to accurately and effectively implement such policies in different regions. Our study provides insights into water policies in China that can better manage natural resources and reduce water poverty in the arid areas around the world.


Assuntos
Insegurança Hídrica , Água , China , Cidades , Políticas , Pobreza
6.
J Healthc Eng ; 2022: 6108241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126932

RESUMO

OBJECTIVES: Previous experiments have shown that growth factor receptors play important role in tumor proliferation, metastasis, and therapeutic effect of chemotherapeutic drugs. At the same time, forkhead box D1 (FOXD1) plays an important role in a variety of signal transmission, but its expression profile was known little about head and neck cancer. The purpose of this experiment was to explore the regulation of FOXD1 on the tumor progression of head and neck cancer and to explore the correlation of FOXD1 on the expression of growth factor receptors (EGFR). METHODS: The bioinformatics online database analyzed the expression of FOXD1 and EGFR in tumor tissues and nontumor tissues. Real-time quantitative PCR was used to detect the FOXD1 and EGFR expression in 45 tumor tissues and 15 nontumor tissues. The plasmid was used to construct FOXD1 overexpressing head and neck squamous cell cancer lines and observe the clonal formation and invasion of tumor cells under the intervention of EGFR-specific antibody-cetuximab. RESULTS: The expression of FOXD1 and EGFR in tumor tissues was higher than that in nontumor tissues. The higher expression of FOXD1 and EGFR was not conducive to the prognosis of patients. The expression of FOXD1 and EGFR was positively correlated, and immunohistochemical analysis showed the high expression of FOXD1 and EGFR has close relation to the advanced stage of the tumor. In vitro cell experiments proved that overexpression of FOXD1 can partially offset the cloning ability of cetuximab on head and neck tumor cells. CONCLUSION: FOXD1 has an important regulatory role in the progression of head and neck cancer, and its abnormally high expression was not conducive to the prognosis of cancer patients. FOXD1 can regulate the expression of growth factor receptors in head and neck cancer, which provides a new idea for the better use of tumor growth factor receptor-specific antibodies for collaborative therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço , Linhagem Celular Tumoral , Cetuximab/metabolismo , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Células Epiteliais/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Receptores de Fatores de Crescimento/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
7.
Huan Jing Ke Xue ; 43(1): 113-122, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989495

RESUMO

Due to the high altitude of plateau cities and strong ultraviolet radiation, the sources and fates of volatile organic compounds show unique characteristics. In this study, the atmospheric volatile organic compound (VOCs) samples were collected at two urban sites and one background site using tank sampling in Lhasa in 2019, and then the composition, concentration, and sources were characterized. The results showed that the average φ(VOCs) in Lhasa was 49.83×10-9, of which the proportion of alkanes was the highest (61%), followed by OVOCs (12%), halogenated hydrocarbons (9%), olefin (9%), aromatic hydrocarbons (5%), and alkynes (4%). The respective contributions of VOCs sources at urban sites, such as Barkhor Street and Radiation Station in Lhasa, were as follows:combustion (64% and 48%) > traffic emission (17% and 31%) > industrial emission (14% and 14%) > solvents and coatings (3% and 3%) ≈plant+background (2% and 4%). The contribution of combustion was large mostly due to local incense burning (especially at Barkhor Street) and heating emissions. Traffic emissions contributed about one third to the VOCs at Radiation Station, which is related to its proximity to the transportation hub and the storage and logistics center upwind. Industrial emissions have a regional impact on ambient VOCs. Under the synergistic influence of meteorology and emissions, VOCs concentration, composition characteristics, and source contribution showed obvious seasonal variations and site differences in the Lhasa area.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Raios Ultravioleta , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
8.
Environ Res ; 206: 112300, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736638

RESUMO

Derived from the biodrying of municipal organic wastes (MOWs), biodried products (BPs) are widely identified as renewable energy sources. In this study, for efficient energy recovery, the pyrolysis characteristics of BPs were investigated by comprehensive kinetic analysis, with special focus on the synergistic effect of bulking agents and the influence of biodegradation. Compared with theoretical raw materials (RMs), it was suggested that the synergistic effect of organics and lignocelluloses in RMs promoted decomposition in Stage 1 (400-570 K), especially for the pyrolysis of RM using sawdust, during which the positive effect achieved decomposition in advance with lower overlap ratio (0.9264) and ΔW (-9.50% at 619.0 K) values. Furthermore, compared with RMs, it was indicated that the kinetic indices (Ea and ln A values) of the BPs were upward in Stage 1 and decreased in Stage 2 due to biodegradation. The results of ΔH, ΔG and ΔS indicated that BP pyrolysis required more heat supply as the reaction progressed but formed a more organized activated complex. In addition, biodegradation observably decreased the generation of gas products and typical functional groups of volatiles during BP pyrolysis, such as CO2 and CO, which presented decreasing ratios of 32.18-42.47% and 30.25-46.47%, respectively. In general, the pyrolysis of BPs was intensified by bulking agents and modified by biodegradation.


Assuntos
Pirólise , Esgotos , Biodegradação Ambiental , Temperatura Alta , Cinética
9.
Contrast Media Mol Imaging ; 2021: 8997105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867117

RESUMO

This work aimed to explore the analysis and diagnosis of children with tic disorder by magnetic resonance imaging (MRI) features under convolutional neural network (CNN), to provide a certain reference basis for clinical identification. A total of 45 children diagnosed with tic disorder in hospital from January 2018 to June 2020 were selected as the research subjects. A total of 30 normal children were selected as the control group. MRI images were collected, and CNN was constructed for image processing. The results showed that the convolutional neural network could significantly improve the speed of MRI reconstruction and can improve the diagnostic accuracy. Compared with normal children, the metabolites in children with tic disorder were slightly increased, but there was no statistical significance (P > 0.05). The results of the Yale score showed that the proportion of children with moderate illness was significantly greater than that of children with mild and severe illness. In short, the pathological changes of tic disorder were effectively discovered by MRI based on CNN algorithms, which can provide a reference for clinical identification.


Assuntos
Redes Neurais de Computação , Transtornos de Tique , Algoritmos , Criança , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Transtornos de Tique/diagnóstico por imagem
10.
Popul Health Manag ; 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34935506

RESUMO

A healthy diet is an important protective factor to prevent cardiometabolic disease. Traditional face-to-face dietary interventions are often episodic, expensive, and may have limited effectiveness, particularly among older adults and people living in rural areas. Telehealth-delivered dietary interventions have proven to be a low-cost and effective alternative approach to improve dietary behaviors among adults with chronic health conditions. In this study, we developed a validated agent-based model of cardiometabolic health conditions to project the impact of expanding telehealth-delivered dietary interventions among older adults in the state of Georgia, a state with a large rural population. We projected the incidence of major cardiometabolic health conditions (type 2 diabetes, hypertension, and high cholesterol) with the implementation of telehealth-delivered dietary interventions versus no intervention among all older adults and 3 subpopulations (older adults with diabetes, hypertension, and high cholesterol, separately). The results showed that expanding telehealth-delivered dietary interventions could avert 22,774 (95% confidence interval [CI]: 22,091-23,457) cases of type 2 diabetes, 19,732 (19,145-20,329) cases of hypertension, and 18,219 (17,672-18,766) cases of high cholesterol for 5 years among older adults in Georgia. The intervention would have a similar effect in preventing cardiometabolic health conditions among the 3 selected subpopulations. Therefore, expanding telehealth-delivered dietary interventions could substantially reduce the burden of cardiometabolic health conditions in the long term among older adults and those with chronic health conditions.

11.
Chem Sci ; 12(44): 14808-14814, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34820096

RESUMO

Manipulating the molecular orbital properties of excited states and the subsequent relaxation processes can greatly alter the emission behaviors of luminophores. Herein we report a vivid example of this, with luminescence conversion from thermally activated delayed fluorescence (TADF) to ultralong room-temperature phosphorescence (URTP) via a facile substituent effect on a rigid benzothiazino phenothiazine tetraoxide (BTPO) core. Pristine BTPO with multiple heteroatoms shows obvious intramolecular charge transfer (ICT) excited states with small exchange energy, featuring TADF. Via delicately functionalizing the BTPO core with peripheral moieties, the excited states of the BTPO derivatives become a hybridized local and charge transfer (HLCT) state in the S1 state and a local excitation (LE) dominated HLCT state in the T1 state, with enlarged energy bandgaps. Upon dispersion in a polymer matrix, the BTPO derivatives exhibit a persistent bright green afterglow with long lifetimes of up to 822 ms and decent quantum yields of up to 11.6%.

12.
World J Clin Cases ; 9(25): 7311-7318, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34616797

RESUMO

Extracellular vesicles (EVs) are cystic vesicles naturally released by most mammalian cells and bacteria. EV contents include proteins, lipids, and nucleic acids. EVs can act as messengers to transmit a variety of molecules to recipient cells and thus play important regulatory roles in intercellular signal transduction. EVs, released by either a host cell or a pathogen, can carry pathogen-associated antigens and thus act as modulators of immune responses. EVs derived from Mycobacterium tuberculosis (Mtb)-infected cells can regulate the innate immune response through various pathways, such as regulating the release of inflammatory cytokines. In addition, EVs can mediate antigen presentation and regulate the adaptive immune response by transmitting immunoregulatory molecules to T helper cells. In this review, we summarize the regulatory roles of EVs in the immune response against Mtb.

13.
Neuroreport ; 32(15): 1248-1254, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34494989

RESUMO

OBJECTIVE: The aim of this study was to investigate the potential therapeutic effects of a newly discovered osteopontin-derived synthetic peptide "RSKKFRR" in a rat model of ischemic stroke. METHODS: A total of 24 male SD rats were randomly divided into three groups. The model of ischemic stroke was made up of the middle cerebral artery occlusion (MACO). The rats were divided into sham operation group (Sham), control group (MACO + PBS) and treatment group (MACO + OPNpt9), eight rats in each group. In the control group and the treatment group, PBS or OPNpt9 was injected into the nasal cavity after MACO once a day, and the area of new blood vessels and the recovery of nerve function were observed 14 days later. Whether the proliferation, migration and tube formation of HUVECs were promoted by OPNpt9 was tested. The expression levels of related proangiogenic factors were also detected. RESULTS: OPNpt9 was found to contribute to cerebral microvascular remodeling and neurological improvement in ischemic rats while promoting endothelial cell migration, proliferation and tube formation in vitro. These effects were mediated by activation of the p-ERK/MMP-9/VEGF pathway. CONCLUSION: In conclusion, OPNpt9 promotes angiogenesis and neurological recovery after ischemic stroke.


Assuntos
Encéfalo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , AVC Isquêmico/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Osteopontina/farmacologia , Animais , Encéfalo/metabolismo , Movimento Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neovascularização Fisiológica/fisiologia , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod
14.
ACS Appl Mater Interfaces ; 13(35): 41773-41781, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432410

RESUMO

Full-color matrix devices based on perovskite light-emitting diodes (PeLEDs) formed via inkjet printing are increasingly attractive due to their tunable emission, high color purity, and low cost. A key challenge for realizing PeLED matrix devices is achieving high-quality perovskite films with a favorable emission structure via inkjet printing techniques. In this work, a narrow phase distribution, high-quality quasi-two-dimensional (quasi-2D) perovskite film without a "coffee ring" was obtained via the introduction of a phenylbutylammonium cation into the perovskite and the use of a vacuum-assisted quick-drying process. Relatively efficient emissions of red, green, and blue (RGB) uniform quasi-2D perovskite films with high photoluminescence quantum yields were cast by the inkjet printing technique. The RGB monochrome perovskite matrix devices with 120 pixel-per-inch resolution exhibited electroluminescence, with maximum external quantum efficiencies of 3.5, 3.4, and 1.0% (for red, green, and blue light emissions, respectively). Furthermore, a full-color perovskite matrix device with a color gamut of 102% (NTSC 1931) was realized. To the best of our knowledge, this is the first report of a full-color perovskite matrix device formed by inkjet printing.

15.
Med Phys ; 48(10): 6051-6059, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34293208

RESUMO

PURPOSE: Dynamic susceptibility contrast (DSC)-MRI is a perfusion imaging technique from which useful quantitative imaging biomarkers can be derived. Relative cerebral blood volume (rCBV) is such a biomarker commonly used for evaluating brain tumors. To account for the extravasation of contrast agents in tumors, post-processing leakage correction is often applied to improve rCBV accuracy. Digital reference objects (DRO) are ideal for testing the post-processing software, because the biophysical model used to generate the DRO can be matched to the one that the software uses. This study aims to develop DROs to validate the leakage correction of software using Weisskoff model and to examine the effect of background signal time curves that are required by the model. METHODS: Three DROs were generated using the Weisskoff model, each composed of nine foreground lesion objects with combinations of different levels of rCBV and contrast leakage parameter (K2). Three types of background were implemented for these DROs: (1) a multi-compartment brain-like background, (2) a sphere background with a constant signal time curve, and (3) a sphere background with signal time curve identical to that of the brain-like DRO's white matter (WM). The DROs were then analyzed with an FDA-cleared software with and without leakage correction. Leakage correction was tested with and without brain segmentation. RESULTS: Accuracy of leakage correction was able to be verified using the brain-like phantom and the sphere phantom with WM background. The sphere with constant background did not perform well with leakage correction with or without brain segmentation. The DROs were able to verify that for the particular software tested, leakage correction with brain segmentation achieved the lowest error. CONCLUSIONS: DSC-MRI DROs with biophysical model matched to that of the post-processing software can be well used for the software's validation, provided that the background signals are also properly simulated for generating the reference time curve required by the model. Care needs to be taken to consider the interaction of the design of the DRO with the software's implementation of brain segmentation to extract the reference time curve.


Assuntos
Neoplasias Encefálicas , Meios de Contraste , Neoplasias Encefálicas/diagnóstico por imagem , Volume Sanguíneo Cerebral , Humanos , Imageamento por Ressonância Magnética , Software
16.
Nanomaterials (Basel) ; 11(5)2021 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-34065118

RESUMO

An environment-friendly inverted indium phosphide red quantum dot light-emitting diode (InP QLED) was fabricated using Mg-doped zinc oxide (ZnMgO) as the electron transport layer (ETL). The effects of ZnMgO ETL on the performance of InP QLED were investigated. X-ray diffraction (XRD) analysis indicated that ZnMgO film has an amorphous structure, which is similar to zinc oxide (ZnO) film. Comparison of morphology between ZnO film and ZnMgO film demonstrated that Mg-doped ZnO film remains a high-quality surface (root mean square roughness: 0.86 nm) as smooth as ZnO film. The optical band gap and ultraviolet photoelectron spectroscopy (UPS) analysis revealed that the conduction band of ZnO shifts to a more matched position with InP quantum dot after Mg-doping, resulting in the decrease in turn-on voltage from 2.51 to 2.32 V. In addition, the ratio of irradiation recombination of QLED increases from 7% to 25% using ZnMgO ETL, which can be attributed to reduction in trap state by introducing Mg ions into ZnO lattices. As a result, ZnMgO is a promising material to enhance the performance of inverted InP QLED. This work suggests that ZnMgO has the potential to improve the performance of QLED, which consists of the ITO/ETL/InP QDs/TCTA/MoO3/Al, and Mg-doping strategy is an efficient route to directionally regulate ZnO conduction bands.

17.
Huan Jing Ke Xue ; 42(6): 2648-2658, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032064

RESUMO

Oxygenated volatile organic compounds (OVOCs) are important intermediates in the troposphere and the most important sources of ozone. Proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF-MS) was used to measure VOCs in the Chengdu Plain, Southwestern China. The diurnal variations, photochemical reactivity, O3 formation potential, and sources were also investigated. The mixing ratios of ten kinds of VOCs (acetaldehyde, acetone, isoprene, Methyl ethyl ketone, Methyl vinyl ketone and Methacrolein, benzene, toluene, styrene, C8 aromatics, and C9 aromatics) were (10.97±4.69)×10-9. The concentrations of OVOCs, aromatic hydrocarbons, and biogenic VOCs were (8.54±3.44)×10-9, (1.53±0.93)×10-9, and (0.90±0.32)×10-9, respectively. Isoprene, acetaldehyde, and m-xylene were the top three photochemically active species with the greatest O3 formation potentials. The dominant three OVOCs species (acetaldehyde, acetone, and MEK) were mainly derived from local biogenic sources and anthropogenic secondary sources, and acetone had a strong regional background level, indicating that pollution in this area is significantly affected by regional transmission. This study deepens the understanding of regional O3 formation mechanisms in southwest China and provides a basis for the scientifically informed control of O3 pollution.

18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 166-169, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829686

RESUMO

The incidence of gastric cancer is the highest among all kinds of malignant tumors in China. Because gastric cancer is very hard to identify in its early stage, the early diagnosis rate of gastric cancer in China is relatively low. At present, the pathological diagnosis of gastric cancer mainly depends on the diagnosis of pathologists. However, the gradual improvement of people's living standards and the growing demand for medical and health care have exacerbated the shortage of medical resources, which has become a even more serious problem. Therefore, there is an urgent need for new technologies to help deal with this challenge. In recent years, with the rapid development of artificial intelligence (AI) and digital pathology, AI-aided pathological diagnosis based on convolutional neural network (CNN) as the core technology is showing promises for improving the diagnostic efficiency of gastric cancer. It is also of great significance for the early diagnosis and treatment of the disease and the reduction of its high incidence and mortality. We herein summarize the application and progress of deep-learning CNN in pathological diagnosis of gastric cancer, as well as the existing problems and prospects of future development.


Assuntos
Neoplasias Gástricas , Inteligência Artificial , China/epidemiologia , Humanos , Redes Neurais de Computação , Neoplasias Gástricas/diagnóstico
20.
Waste Manag ; 126: 585-596, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862510

RESUMO

Polylactic acid (PLA) plastic is becoming a popular alternative to traditional petroleum-based plastics, but the biodegradability in engineered biological system is still a matter of concern. In this study, the biodegradability of PLA plastic at mesophilic and thermophilic AD were investigated, and a hydrothermal pretreatment was proposed to enhance the hydrolysis of PLA plastic and subsequent biomethanization. For raw PLA plastic, the biodegradation results indicated that PLA was hardly biodegraded at mesophilic conditions (only 50.5 ± 0.5 mL/g VS after 146 days). Although it was converted into biogas at thermophilic conditions after long incubation period (442.6 ± 1.1 mL/g VS), the long digestion time (T90 95.8 days) was destined to be infeasible for practical application. In contrast, hydrothermal pretreatment significantly enhanced the hydrolysis rates of PLA plastic in AD process from 0.001 day-1 for raw PLA plastic to 0.004-0.111 day-1. By balancing biogas production efficiency, energy and reagent cost, the conditions of 200 °C, 10 min and no alkali addition were recommended for hydrothermal pretreatment of waste PLA plastic in practice. At the optimized hydrothermal pretreatment conditions, 460.1 ± 25.0 mL/g VS was achieved in less than 30 days, which was comparable for AD of food waste (FW). Furthermore, LC-QEMS analysis proved that cleavages of ester bonds in PLA and its reaction with water molecule was the mechanism of triggering the hydrothermally decomposition of PLA. These results suggested the PLA-plastic waste co-mingled with OFMSW could be efficiently biomethanized into biogas by involving a mild hydrothermal pretreatment in practical application.


Assuntos
Eliminação de Resíduos , Anaerobiose , Biocombustíveis , Reatores Biológicos , Alimentos , Cinética , Metano , Plásticos , Poliésteres
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