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1.
Sci Rep ; 14(1): 6452, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499599

RESUMO

During the coal and rock mass fracture process, elastic properties are released and vibration waves are radiated outward. The energy attenuation characteristics of these waves can describe the cumulative damage and elastic energy accumulation of the mass. To investigate coal and rock mass failure characteristics and energy attenuation rules during rockburst, numerical simulation and laboratory testing were utilized to study the energy transfer laws under various parameters. Six variables, including elastic modulus, Poisson's ratio, bulk density, cohesion, internal friction angle, and void ratio, were selected to simulate the rockburst energy release process under different parameter combinations by adding surface pressure to the model. The coal and rock mass energy attenuation coefficient was obtained by fitting the node energy straight line using the least squares method. The six variables' influence on vibration wave energy transfer was obtained using analytic hierarchy process program written in MATLAB, and a comprehensive calculation formula was proposed. Using the energy attenuation coefficient, the rock layer energy diffusion distance was calculated and compared with the roof collapse rock layer step distance, resulting in the roof rock layer cutting distance determination. By roof rock strata precutting, rockburst occurrence can be prevented, ensuring safe and efficient coal mine production.

2.
Coron Artery Dis ; 35(2): 114-121, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38189652

RESUMO

BACKGROUND: The purpose of this study was to evaluate the relationship between remnant cholesterol (RC) to high-density lipoprotein cholesterol (HDL-C) ratio and the risk of coronary artery disease (CAD). We also investigated the clinical value of RC/HDL-C ratio in evaluating the severity of CAD and in predicting the short-term prognosis of CAD patients. METHODS: In total, 615 patients were enrolled and they were classified into a CAD group (418 cases) and a normal group (197 cases) according to the results of coronary angiography. Serum RC/HDL-C ratio and Gensini score were calculated. Multivariate logistic regression and receiver operating characteristic (ROC) curves were employed to evaluate the association between RC/HDL-C ratio and CAD. The effect of RC/HDL-C ratio on the progression of major adverse cardiovascular events (MACEs) was also explored. RESULTS: Increased RC/HDL-C ratio was associated with an increased risk of CAD (OR: 11.122; 95% CI: 5.903-20.954; P  < 0.001). When stratified by CAD subtypes, increased RC/HDL-C ratio was correlated with a greater risk of acute coronary syndrome (ACS) (OR:1.549; 95% CI: 1.014-2.364; P  < 0.05). Compared with the first quartile, the 4th quartile of RC/HDL-C ratio had a 9.774-fold ( P  = 0.000) increase in the odds ratio for CAD, and a 2.241-fold ( P  = 0.017) increase in the odds ratio for ACS. RC/HDL-C ratio was an independent determinant of Gensini score ≥32 (OR: 2.138, 95% CI:1.389-3.292, P  < 0.01), and multi-branch (MVD) (OR: 2.245; 95% CI: 1.468-3.443; P  < 0.001). The prevalence of Gensini score ≥32 and MVD in the 4th quartile of RC/HDL-C ratio group were much higher than that of other quartile groups ( P  < 0.01). Moreover, the areas under the ROC for the predictive value of RC/HDL-C ratio for CAD, ACS, Gensini score ≥32, and MVD were 0.702, 0.563, 0.602, and 0.669, respectively. Furthermore, the incidence of MACEs was significantly increased in CAD patients with levels of RC/HDL-C ratio ( P  < 0.05). CONCLUSION: RC/HDL-C ratio plays an important role in the progression and severity of CAD.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , HDL-Colesterol , LDL-Colesterol , Colesterol , Angiografia Coronária , Síndrome Coronariana Aguda/complicações , Fatores de Risco
3.
Pest Manag Sci ; 79(2): 729-740, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36258287

RESUMO

BACKGROUND: Both arrhenotoky (sexual reproduction of females and asexual reproduction of males) and thelytoky (asexual reproduction of females) occur within the order Hymenoptera. The existence of both thelytokous and arrhenotokous strains within one species provides an opportunity to compare the biocontrol efficiency between two reproductive modes. The parasitoid Neochrysocharis formosa (Westwood) (Hymenoptera: Eulophidae) has thelytokous and arrhenotokous strains with sympatric distributions. This parasitoid is used to control invasive leafminers through feeding, stinging, and parasitization. To compare the biocontrol efficiency of the two strains, we analyzed life tables and host-killing parameters of these two strains reared on the leafminer Liriomyza sativae Blanchard using the age-stage, two-sex life table and the CONSUME-MSChart software. RESULTS: Our results showed that the intrinsic rate of increase (r), finite rate of increase (λ), and net reproduction rate (R0 ) of the thelytokous strain were significantly higher than those of the arrhenotokous strain. The thelytokous females also performed better than the arrhenotokous females for the net host-feeding rate, net host-stinging rate, and net host-killing rate, but not the finite parasitism rate. Conclusively, the finite host-killing rate of the thelytokous strain (0.8720 ± 0.0516) was significantly higher than that of the arrhenotokous strain (0.5914 ± 0.0832). CONCLUSION: We concluded that thelytokous N. formosa is a better candidate as a biocontrol agent than arrhenotokous N. formosa to control leafminers. Our results shed light on how to choose a better biocontrol agent for integrated pest management (IPM) based on biological control, especially for co-occurring thelytokous and arrhenotokous parasitoids. © 2022 Society of Chemical Industry.


Assuntos
Himenópteros , Vespas , Animais , Feminino , Masculino , Taiwan , Reprodução
4.
Front Public Health ; 9: 728768, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722440

RESUMO

Aim: The aim of this study was to analyze the changes in incidence of notifiable infectious diseases in China under the prevention and control measures of COVID-19. Methods: Using descriptive epidemiological methods, data were collected from the official website of the Health Commission of the People's Republic of China, and the prevalence characteristics of notifiable infectious diseases in the country in 2020 were analyzed and compared with the historical data in 2019. Monthly reporting data on influenza and tuberculosis from 2015 to 2019 were also collected. Results: Except for COVID-19, the total number of notifiable infectious diseases cases in 2020 was 6,366,176, a decrease of 41.38% year-on-year compared with 2019. Category B and C notifiable infectious diseases decreased by 14.84 and 54.98% year-on-year, respectively (P < 0.01). The top three incidence rates were influenza (87.63 cases/100,000), hepatitis B (81.36 cases/100,000) and other infectious diarrhea (76.33 cases/100,000). Three types of diseases with the largest decline were influenza (-2,280,502 cases), hand-foot-mouth disease (-1,174,588 cases), and other infectious diarrhea diseases (-275,746 cases). Compared with 2019, respiratory infectious diseases were reported to be in the largest decline in 2020, followed by intestinal infectious diseases, blood-borne and sexually transmitted diseases, natural foci, and insect-borne infectious diseases. The monthly reported incidences of influenza and tuberculosis in 2020 were lower than the average of the previous 5 years. Conclusion: In 2020, the incidence of most notifiable infectious diseases in China showed a downward trend, non-pharmaceutical interventions (NPIs)such as the wearing of masks, frequent hand-washing, more ventilation, less gathering, etc, played an positive role in the prevention and control of respiratory and intestinal infectious diseases. The various public health intervention strategies and measures adopted by China to contain COVID-19 can provide a reference for the prevention and control of infectious diseases in other countries.


Assuntos
COVID-19 , Doenças Transmissíveis , China/epidemiologia , Doenças Transmissíveis/epidemiologia , Humanos , Incidência , SARS-CoV-2
5.
ACS Omega ; 4(2): 3933-3945, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31459602

RESUMO

Herein, we report a novel type of smart graphene oxide nanocomposites (MGO@PNB) with excellent magnetism and high thermosensitive ion-recognition selectivity of lead ions (Pb2+). The MGO@PNB are fabricated by immobilizing superparamagnetic Fe3O4 nanoparticles (NPs) and poly(N-isopropylacrylamide-co-benzo-18-crown-6 acrylamide) thermosensitive microgels (PNB) onto graphene oxide (GO) nanosheets using a simple one-step solvothermal method and mussel-inspired polydopamine chemistry. The PNB are composed of cross-linked poly(N-isopropylacrylamide) (PNIPAM) chains with numerous appended 18-crown-6 units. The 18-crown-6 units serve as hosts that can selectively recognize and capture Pb2+ from aqueous solution, and the PNIPAM chains act as a microenvironmental actuator for the inclusion constants of 18-crown-6/Pb2+ host-guest complexes. The loaded Fe3O4 NPs endow the MGO@PNB with convenient magnetic separability. The fabricated MGO@PNB demonstrate remarkably high ion-recognition selectivity of Pb2+ among the coexisting metal ions because of the formation of stable 18-crown-6/Pb2+ inclusion complexes. Most interestingly, the MGO@PNB show excellent thermosensitive adsorption ability toward Pb2+ due to the incorporation of PNIPAM functional chains on the GO. Further thermodynamic studies indicate that the adsorption of Pb2+ onto the MGO@PNB is a spontaneous and endothermic process. The adsorption kinetics and isotherm data can be well described by the pseudo-second-order kinetic model and the Langmuir isotherm model, respectively. Most importantly, the Pb2+-loaded MGO@PNB can be more easily regenerated by alternatively washing with hot/cold water than the commonly used regeneration methods. Such multifunctional graphene oxide nanocomposites could be used for specific recognition and removal of Pb2+ from water environment.

6.
Rev Port Cardiol (Engl Ed) ; 38(1): 65.e1-65.e3, 2019 Jan.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30685294

RESUMO

Superior vena cava (SVC) syndrome is typically dramatic. Although the diagnosis is usually easy, elucidation of the etiology is difficult. We present a patient who developed SVC syndrome early after transvenous pacemaker implantation and who was subsequently diagnosed with lung carcinoma. The pathogenesis seems to be explained by a combination of two etiologies: lung carcinoma plus transvenous pacemaker implantation. We emphasize that common etiologies such as malignancy should be considered first when faced with SVC syndrome.


Assuntos
Neoplasias Pulmonares/complicações , Marca-Passo Artificial/efeitos adversos , Síndrome da Veia Cava Superior/etiologia , Idoso de 80 Anos ou mais , Evolução Fatal , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Síndrome da Veia Cava Superior/diagnóstico , Fatores de Tempo , Tomografia Computadorizada por Raios X
7.
Coron Artery Dis ; 25(5): 433-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24608795

RESUMO

BACKGROUND AND AIMS: Our aim was to examine whether the combined use of apolipoprotein B (apoB)/apolipoprotein A1 (apoA1) and non-high-density lipoprotein cholesterol (non-HDL-C) was useful before routine clinical lipid measurement in predicting coronary heart disease (CHD). PATIENTS AND METHODS: In total, 826 patients were enrolled and they were classified into a CHD group (532 cases) and a normal group (294 cases) according to the results of coronary angiography. Laboratory data including fasting lipid profile were obtained after an overnight fast. Serum apoB/apoA1 ratio and non-HDL-C were calculated. Logistic regression was applied to estimate the cross-sectional association between the apoB/apoA1 ratio, non-HDL-C, and CHD. Receiver operating characteristics curve analysis was used to determine the value of apoB/apoA1 ratio and non-HDL-C in the diagnosis of CHD. RESULTS: The associations with an increased risk of CHD were much stronger for the apoB/apoA1 ratio [odds ratio (OR)=8.941, 95% confidence interval (CI) 4.363-18.323] than for non-HDL-C (OR=1.373, 95% CI 1.163-1.622). The patients in the top quartile of the apoB/apoA1 distribution had an OR of 7.321 (95% CI 3.891-13.771) compared with those in the bottom quartile. Patients with combined high levels of apoB/apoA1 and non-HDL-C (N=92, 79.31%) had the highest risk of CHD. The combined use of apoB/apoA1 ratio and non-HDL-C (0.762; 95% CI 0.677-0.847) showed greater receiver operating characteristics area than its individual components or other lipid profiles. CONCLUSION: The combination of apoB/apoA1 and non-HDL-C had even greater predictive value than its individual components or other lipid profiles.


Assuntos
Apolipoproteína A-I/sangue , Apolipoproteína B-100/sangue , Colesterol/sangue , Doença das Coronárias/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Regulação para Cima
8.
Virus Res ; 135(1): 175-80, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18455826

RESUMO

The combination of sodium butyrate (NaB) and ganciclovir (GCV) was considered to be a noteworthy therapeutic strategy in Epstein-Barr virus (EBV)-associated cancers. However, clinical studies have indicated that an extremely high dose of NaB is required to obtain the expected curative efficacy. This obviously limits the practical clinical application of the two drugs combined. In this study, we investigated the possibility of sensitizing tumor cells to NaB and GCV mediated cytotoxicity by modulating intracellular signal pathways. The results showed that the disruption of Ras/Raf activity by expressing dominant negative forms of both Ras and Raf-1 did not alter the potency of the NaB and GCV combination in the EBV-positive cell line, B95-8. However, blocking Akt activity by expressing its dominant negative form remarkably promoted NaB and GCV-mediated cytotoxicity via a thymidine kinase (TK)-independent mechanism. Interestingly, it was found that the constitutive activation of mitogen-activated protein kinase kinase kinase 1 (MEKK1) dramatically enhanced the sensitization of the cells to the combination of NaB and GCV, accompanied with an increase in TK expression in B95-8 cells. These results suggest that interfering with either the Akt or MEKK1 signaling pathway may be a useful therapeutic strategy to increase the sensitivity of EBV-positive tumor cells to the combination of NaB and GCV.


Assuntos
Butiratos/farmacocinética , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Ganciclovir/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Infecções por Vírus Epstein-Barr/virologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MAP Quinase Quinase Quinase 1/genética , MAP Quinase Quinase Quinase 1/metabolismo , Neoplasias/virologia , Proteína Oncogênica p21(ras)/genética , Proteína Oncogênica p21(ras)/metabolismo , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Timidina Quinase/genética , Timidina Quinase/metabolismo , Quinases raf/genética , Quinases raf/metabolismo
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