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Power of SAR Imagery and Machine Learning in Monitoring Ulva prolifera:A Case Study of Sentinel-1 and Random Forest
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作者 ZHENG Longxiao WU Mengquan +5 位作者 XUE Mingyue WU Hao LIANG Feng LI Xiangpeng HOU Shimin LIU Jiayan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1134-1143,共10页
Automatically detecting Ulva prolifera(U.prolifera)in rainy and cloudy weather using remote sensing imagery has been a long-standing problem.Here,we address this challenge by combining high-resolution Synthetic Apertu... Automatically detecting Ulva prolifera(U.prolifera)in rainy and cloudy weather using remote sensing imagery has been a long-standing problem.Here,we address this challenge by combining high-resolution Synthetic Aperture Radar(SAR)imagery with the machine learning,and detect the U.prolifera of the South Yellow Sea of China(SYS)in 2021.The findings indicate that the Random Forest model can accurately and robustly detect U.prolifera,even in the presence of complex ocean backgrounds and speckle noise.Visual inspection confirmed that the method successfully identified the majority of pixels containing U.prolifera without misidentifying noise pixels or seawater pixels as U.prolifera.Additionally,the method demonstrated consistent performance across different im-ages,with an average Area Under Curve(AUC)of 0.930(+0.028).The analysis yielded an overall accuracy of over 96%,with an average Kappa coefficient of 0.941(+0.038).Compared to the traditional thresholding method,Random Forest model has a lower estimation error of 14.81%.Practical application indicates that this method can be used in the detection of unprecedented U.prolifera in 2021 to derive continuous spatiotemporal changes.This study provides a potential new method to detect U.prolifera and enhances our under-standing of macroalgal outbreaks in the marine environment. 展开更多
关键词 Ulva prolifera random Forest Sentinel-1 Synthetic Aperture Radar(Sar)image machine learning remote sensing Google Earth Engine South Yellow Sea of China
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Does type 1 diabetes serve as a protective factor against inflammatory bowel disease:A Mendelian randomization study
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作者 Ke-Ke Tong Yun-Feng Yu +3 位作者 Xin-Yu Yang Jing-Yi Wu Rong Yu Chuan-Chuan Tan 《World Journal of Diabetes》 SCIE 2024年第7期1551-1561,共11页
BACKGROUND The impact of type 1 diabetes(T1D)on inflammatory bowel disease(IBD)remains unclear.AIM To analyze the causal relationship between T1D and IBD using Mendelian randomization(MR).METHODS Single nucleotide pol... BACKGROUND The impact of type 1 diabetes(T1D)on inflammatory bowel disease(IBD)remains unclear.AIM To analyze the causal relationship between T1D and IBD using Mendelian randomization(MR).METHODS Single nucleotide polymorphisms were sourced from FinnGen for T1D,IBD,ulcerative colitis(UC)and Crohn’s disease(CD).Inverse variance-weighted,MREgger,and weighted median tests were used to assess exposure-outcome causality.The MR-Egger intercept was used to assess horizontal pleiotropy.Cochran’s Q and leave-one-out method were used to analyze heterogeneity and sensitivity,respectively.RESULTS Our MR analysis indicated that T1D was associated with a reduced risk of IBD[odds ratio(OR):0.959;95%confidence interval(CI):0.938-0.980;P<0.001]and UC(OR:0.960;95%CI:0.929-0.992;P=0.015),with no significant association observed in terms of CD risk(OR:0.966;95%CI:0.913-1.022;P=0.227).The MR-Egger intercept showed no horizontal pleiotropy(P>0.05).Cochran’s Q and leave-one-out sensitivity analyses showed that the results were not heterogeneous(P>0.05)and were robust.CONCLUSION This MR analysis suggests that T1D serves as a potential protective factor against IBD and UC but is independent of CD. 展开更多
关键词 Type 1 diabetes Inflammatory bowel disease Ulcerative colitis Crohn’s disease Mendelian randomization
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Robustness self-testing of states and measurements in the prepare-and-measure scenario with 3 → 1 random access code
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作者 Shi-Hui Wei Fen-Zhuo Guo +1 位作者 Xin-Hui Li Qiao-Yan Wen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期144-151,共8页
Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(... Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors. 展开更多
关键词 ROBUSTNESS SELF-TESTING prepare-and-measure SCENarIO 3 1 random access CODE
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TESTING OF CORRELATION AND HETEROSCEDASTICITY IN NONLINEAR REGRESSION MODELS WITH DBL(p,q,1) RANDOM ERRORS
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作者 刘应安 韦博成 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期613-632,共20页
Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity (K... Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity (Kantz and Schreiber (1997)). Tsai (1986) introduced a composite test for autocorrelation and heteroscedasticity in linear models with AR(1) errors. Liu (2003) introduced a composite test for correlation and heteroscedasticity in nonlinear models with DBL(p, 0, 1) errors. Therefore, the important problems in regression model axe detections of bilinearity, correlation and heteroscedasticity. In this article, the authors discuss more general case of nonlinear models with DBL(p, q, 1) random errors by score test. Several statistics for the test of bilinearity, correlation, and heteroscedasticity are obtained, and expressed in simple matrix formulas. The results of regression models with linear errors are extended to those with bilinear errors. The simulation study is carried out to investigate the powers of the test statistics. All results of this article extend and develop results of Tsai (1986), Wei, et al (1995), and Liu, et al (2003). 展开更多
关键词 DBL(p Q 1 random errors nonlinear regression models score test HETEROSCEDASTICITY CORRELATION
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Markov Chains Based on Random Generalized 1-Flipper Operations for Connected Regular Multi-digraphs
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作者 邓爱平 伍陈晨 +1 位作者 王枫杰 胡宇庭 《Journal of Donghua University(English Edition)》 CAS 2023年第1期110-115,共6页
The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-F... The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-Flipper operation preserves the regularity and weak connectivity of multi-digraphs.The generalized 1-Flipper operation is proved to be symmetric.Moreover,it is presented that a series of random generalized 1-Flipper operations eventually lead to a uniform probability distribution over all connected d-regular multi-digraphs without loops. 展开更多
关键词 random graph transformation regular multi-digraph Markov chain 1-Flipper triangle reverse
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Postoperative chemotherapy with S-1 plus oxaliplatin versus S-1alone in locally advanced gastric cancer(RESCUE-GC study): a protocol for a phase Ⅲ randomized controlled trial 被引量:5
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作者 Xiang Hu Lin Chen +29 位作者 Yian Du Biao Fan Zhaode Bu Xin Wang Yingjiang Ye Zhongtao Zhang Gang Xiao Fei Li Qingsi He Guoli Li Xian Shen Bin Xiong Liming Zhu Jiwei Liui Lian Liu Tao Wu Jing Zhou Jun Zhang Gang Zhao Xulin Wang Pin Liang Xinxin Wang Yan Zhang Xiaojiang Wu Ji Zhang Xin Ji Xianglong Zong Tao Fu Ziyu Jia Jiafu Ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第2期144-148,共5页
Background: The ACTS-GC study had shown postoperative adiuvant therapy with S-1 improved survival of patients with locally advanced gastric cancer. Addition of oxaliplatin to S-1 is considered to be acceptable as one... Background: The ACTS-GC study had shown postoperative adiuvant therapy with S-1 improved survival of patients with locally advanced gastric cancer. Addition of oxaliplatin to S-1 is considered to be acceptable as one of the treatment options for gastric cancer patients after radical gastrectomy with D2 lymph node excision. Methods: We have commenced a randomized phase III trial in December 2016 to evaluate S-I plus oxaliplatin compared with S-1 alone in the adjuvant setting for locally advanced gastric cancer. A total of 564 patients will be accrued from 13 Chinese institutions in two years. The primary endpoint is 3-year relapse-free survival. The secondary endpoints are 5-year overall survival, proportion of patients who complete the postoperative chemotherapy and incidence of adverse events. Ethic and dissemination: The trial has been approved by the institutional review board of each participating institution and it was activated on December, 2016. The enrollment will be finished in December, 2018. Patient's follow-up will be ended until December, 2023. Trial registration: ClinicalTrials.gov, identifier: NCT02867839. Registered on August 4, 2016. 展开更多
关键词 Locally advanced gastric cancer S-1 plus oxaliplatin randomized phase HI trial
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Spin-1 Blume-Capel model with longitudinal random crystal and transverse magnetic fields:A mean-field approach 被引量:2
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作者 Erhan Albayrak 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期494-498,共5页
The spin-1 Blume–Capel model with transverse and longitudinal external magnetic fields h, in addition to a longitudinal random crystal field D, is studied in the mean-field approximation. It is assumed that the cryst... The spin-1 Blume–Capel model with transverse and longitudinal external magnetic fields h, in addition to a longitudinal random crystal field D, is studied in the mean-field approximation. It is assumed that the crystal field is either turned on with probability p or turned off with probability 1 p on the sites of a square lattice. Phase diagrams are then calculated on the reduced temperature crystal field planes for given values of γ=Ω/J and p at zero h. Thus, the effect of changing γ and p are illustrated on the phase diagrams in great detail and interesting results are observed. 展开更多
关键词 random crystal field transverse field spin-1 Blume–Capel model
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Influence of education training in patients with type 2 diabetes in the improvement of lifestyle and biochemical characteristics: a randomized controlled trial 被引量:1
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作者 Alida Ramaj Fatjona Kamberi 《Frontiers of Nursing》 CAS 2019年第4期293-299,共7页
Objective: The objective of this randomized controlled trial study was to evaluate the education training in relation to lifestyle improvement in patients with type 2 diabetes through its influence in the levels of gl... Objective: The objective of this randomized controlled trial study was to evaluate the education training in relation to lifestyle improvement in patients with type 2 diabetes through its influence in the levels of glycated hemoglobin(HbA1 c), blood pressure, triglyceride, cholesterol levels, and body mass index(BMI).Methods: The study included patients with type 2 diabetes randomly selected from 20 residential areas in Tirana, Albania where family physicians provide services. The sample size in total was 200 patients in both groups(control and intervention). The education training(four sessions) was conducted by trained nursing staff for 6 months. Patients were screened for the biochemical profile before and after the intervention. To compare the groups with respect to the interest outcomes, the t-test was used. The value of P < 0.05 was considered significant.Results: There were 104 male patients and 96 female patients. The mean age was 54.9 ± 8.7. No significant differences were found between the study groups in relation to clinical and biochemical data before the education sessions. After the intervention, in the intervention group, the mean level of HbA1 c was significantly lower than the value in the control group(6.2% vs 6.8%, P = 0.001) as well as for the mean values of BMI. The mean reduction(more than 15%) in HbA1 c after the intervention was 43% in the intervention group and 2% in the control group(OR = 36.9, P < 0.05). Differences in BMI, HbA1 c, triglycerides, and cholesterol were more significantly visible in the intervention group. However, the difference in systolic and diastolic blood pressure values was almost the same(P > 0.05).Conclusions: The results of this study further support that the approach for education of patients with type 2 diabetes on changing lifestyle benefit the patient in controlling diabetes. It is believed that the establishment of diabetes education classes in health centers is an important investment in improving the management of type 2 diabetes. 展开更多
关键词 type 2 diabetes health education MANAGEMENT randomized controlled trial HBA1C BMI
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Effects of Film Thickness and Ar/O2 Ratio on Resistive Switching Characteristics of HfOx-Based Resistive-Switching Random Access Memories
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作者 郭婷婷 谭婷婷 刘正堂 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期125-128,共4页
Cu/HfOx/n^+Si devices are fabricated to investigate the influence of technological parameters including film thickness and Ar/02 ratio on the resistive switching (RS) characteristics of HfOx films, in terms of swit... Cu/HfOx/n^+Si devices are fabricated to investigate the influence of technological parameters including film thickness and Ar/02 ratio on the resistive switching (RS) characteristics of HfOx films, in terms of switch ratio, endurance properties, retention time and multilevel storage. It is revealed that the RS characteristics show strong dependence on technological parameters mainly by altering the defects (oxygen vacancies) in the film. The sample with thickness of 2Onto and Ar/O2 ratio of 12:3 exhibits the best RS behavior with the potential of multilevel storage. The conduction mechanism of all the films is interpreted based on the filamentary model. 展开更多
关键词 Effects of Film Thickness and ar/O2 Ratio on Resistive Switching Characteristics of HfOx-Based Resistive-Switching random Access Memories
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Safety,immunogenicity,and preliminary efficacy of a randomized clinical trial ofomicron XBB.1.5-containing bivalent mRNA vaccine
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作者 Xuanjing Yu Wei Yang +15 位作者 Wei Li Na Wan Guanghong Yan Zumi Zhou Xiao Zhu Wei Su Yani Li Chenyu Xing Sifan Duan Houze Yu Xinshuai Zhao Chunmei Li Taicheng Zhou Dingyun You Jia Wei Zijie Zhang 《hLife》 2024年第3期113-125,共13页
Periodically updating coronavirus disease 19(COVID-19)vaccines that offer broad-spectrum protection is needed giventhe strong immune evasion by the circulating omicron sublineages.The effectiveness of prototype and BA... Periodically updating coronavirus disease 19(COVID-19)vaccines that offer broad-spectrum protection is needed giventhe strong immune evasion by the circulating omicron sublineages.The effectiveness of prototype and BA.4/5-containing bivalent mRNA vaccines is reduced when XBB subvariants predominate.We initiated an observer-blinded,threearms study in 376 patients in Chinese individuals aged from 18 to 55 years old who had previously received three dosesCOVID-19 vaccine.Immunogenicity in terms of neutralizing antibodies elicited by a 30-mg dose of XBB.1.5-containingbivalent vaccine(RQ3027),a 30-mg dose of BA.2/BA.5-Alpha/Beta bivalent vaccine(RQ3025)and their precedent 30-mg Alpha/Beta(combined mutations)monovalent mRNA vaccine(RQ3013)and safety are primary and secondary endpoints,respectively.We recorded prescribed COVID-19 cases to explore the preliminary efficacy of three vaccines.RQ3027 and RQ3025 boosters elicited superior neutralizing antibodies(NAbs)against XBB.1.5,XBB.1.16,XBB.1.9.1,and JN.1 compared to RQ3013 at day 14 in participants without SARS-CoV-2 infection.All study vaccines were welltolerated without serious adverse reactions identified.The incidence rates per 1000 person-years of COVID-19 casesduring the 2nd-19th week after randomization were lowest in RQ3027.Overall,our data show that XBB.1.5-containingbivalent booster generated superior immunogenicity and better protection against newer severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants compared to BA.2/BA.5-containing bivalent and Alpha/Beta monovalentwith no new safety concerns. 展开更多
关键词 severe acute respiratory syndrome coronavirus 2(SarS-CoV-2) JN.1 XBB lineages coronavirus disease19(COVID-19)vaccine mRNA bivalent vaccine randomized clinical trial
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The Effect of Chloroquine on Pro-Inflammatory Cytokines Levels in Graves’ Disease: Historical Cohort from a Pilot Randomized Controlled Trial
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作者 Hadi Moattar Hamideh Moosapour +1 位作者 Akbar Soltani Bagher Larijani 《Pharmacology & Pharmacy》 2013年第4期392-397,共6页
Objectives: Analyzing the trend in the serum inflammatory cytokines levels in a historical cohort of patients treated with combination of chloroquine and methimazole. Material and methods: We analyzed the pro-inflamma... Objectives: Analyzing the trend in the serum inflammatory cytokines levels in a historical cohort of patients treated with combination of chloroquine and methimazole. Material and methods: We analyzed the pro-inflammatory serum cytokines level [Interleukin-6(IL-6), Tumor Necrosis Factor alpha (TNF-α), Interleukin 1 alpha (IL-1 α) and Interferon gamma (INF-γ)] in the stored blood samples of 22 patients with Graves’ disease who previously randomized to receive either chloroquine and methimazole combination therapy or methimazole monotherapy. Total T3, T4 and TSH levels were measured by an enzyme linked immunosorbent assay (ELISA) method (DRG, New York, USA) and the result was published previously. In this study we used an ELISA method (Bender Medsystem Vienna Austria) to measure serum pro-inflammatory cytokines in the first 6 months of trial. Results: No significant differences in serum cytokines concentration were observed between the two treatment groups (p > 0.05). Although it was not statistically significant, serum INF-gamma concentration tended to be lower in the chloroquine group after four months of therapy (p = 0.12). Conclusion: In this study we found changes in the serum thyroid hormones level did not accompany concomitant changes in the serum cytokines levels in two treatment groups. Therefore it is possible that chloroquine reduce serum thyroid hormones levels independent of its immunomodulatory effect. 展开更多
关键词 CHLOROQUINE Cytokines Graves’ Disease randomized Controlled Trial INTERLEUKIN-1 INTERLEUKIN-6 INTERLEUKIN-1 Alpha Tumor Necrosis FACTOR-ALPHA Interferon Gamma
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L_1-Norm Estimation and Random Weighting Method in a Semiparametric Model 被引量:3
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作者 Liu-genXue Li-xingZhu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第2期295-302,共8页
In this paper, the L_1-norm estimators and the random weighted statistic fora semiparametric regression model are constructed, the strong convergence rates of estimators areobtain under certain conditions, the strong ... In this paper, the L_1-norm estimators and the random weighted statistic fora semiparametric regression model are constructed, the strong convergence rates of estimators areobtain under certain conditions, the strong efficiency of the random weighting method is shown. Asimulation study is conducted to compare the L_1-norm estimator with the least square estimator interm of approximate accuracy, and simulation results are given for comparison between the randomweighting method and normal approximation method. 展开更多
关键词 L_1-norm estimation random weighting method semiparametric regression model
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Polo-like kinase 1 as a biomarker predicts the prognosis and immunotherapy of breast invasive carcinoma patients
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作者 JUAN SHEN WEIYU ZHANG +11 位作者 QINQIN JIN FUYU GONG HEPING ZHANG HONGLIANG XU JIEJIE LI HUI YAO XIYA JIANG YINTING YANG LIN HONG JIE MEI YANG SONG SHUGUANG ZHOU 《Oncology Research》 SCIE 2024年第2期339-351,共13页
Invasive breast carcinoma(BRCA)is associated with poor prognosis and high risk of mortality.Therefore,it is critical to identify novel biomarkers for the prognostic assessment of BRCA.Methods:The expression data of po... Invasive breast carcinoma(BRCA)is associated with poor prognosis and high risk of mortality.Therefore,it is critical to identify novel biomarkers for the prognostic assessment of BRCA.Methods:The expression data of polo-like kinase 1(PLK1)in BRCA and the corresponding clinical information were extracted from TCGA and GEO databases.PLK1 expression was validated in diverse breast cancer cell lines by quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting.Single sample gene set enrichment analysis(ssGSEA)was performed to evaluate immune infiltration in the BRCA microenvironment,and the random forest(RF)and support vector machine(SVM)algorithms were used to screen for the hub infiltrating cells and calculate the immunophenoscore(IPS).The RF algorithm and COX regression model were applied to calculate survival risk scores based on the PLK1 expression and immune cell infiltration.Finally,a prognostic nomogram was constructed with the risk score and pathological stage,and its clinical potential was evaluated by plotting calibration charts and DCA curves.The application of the nomogram was further validated in an immunotherapy cohort.Results:PLK1 expression was significantly higher in the tumor samples in TCGA-BRCA cohort.Furthermore,PLK1 expression level,age and stage were identified as independent prognostic factors of BRCA.While the IPS was unaffected by PLK1 expression,the TMB and MATH scores were higher in the PLK1-high group,and the TIDE scores were higher for the PLK1-low patients.We also identified 6 immune cell types with high infiltration,along with 11 immune cell types with low infiltration in the PLK1-high tumors.A risk score was devised using PLK1 expression and hub immune cells,which predicted the prognosis of BRCA patients.In addition,a nomogram was constructed based on the risk score and pathological staging,and showed good predictive performance.Conclusions:PLK1 expression and immune cell infiltration can predict post-immunotherapy prognosis of BRCA patients. 展开更多
关键词 Breast invasive carcinoma(BRCA) Polo-like kinase 1(PLK 1) random forest(RF) Support vector machine(SVM) Immune infiltration
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m6A甲基转移酶METTL3通过β‐arrestin 1/p65调控结肠癌细胞增殖
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作者 江洁 刘慧玲 吴斌 《解剖学研究》 CAS 2024年第6期579-583,共5页
目的探讨m6A甲基转移酶METTL3通过β-arrestin 1/p65在结肠癌细胞中的作用机制。方法使用结肠癌细胞系HCT116,应用荧光定量PCR、Western blot测定结肠癌细胞中METTL3、β-arrestin 1及增值蛋白PCNA、Cyclin D1及Cyclin E的表达水平;利... 目的探讨m6A甲基转移酶METTL3通过β-arrestin 1/p65在结肠癌细胞中的作用机制。方法使用结肠癌细胞系HCT116,应用荧光定量PCR、Western blot测定结肠癌细胞中METTL3、β-arrestin 1及增值蛋白PCNA、Cyclin D1及Cyclin E的表达水平;利用细胞转染及细胞克隆实验,观察METTL3、β-arres-tin1和p65在结肠癌细胞增殖中的作用。结果METTL3和β-arrestin 1在结肠癌细胞中表达升高(以actin作为内参基因,与正常对照组比较,P<0.05)。结肠癌细胞转染METTL3-shRNA后,转染组灰度(0.36±0.046)较对照组(1.27±0.14)明显减少(P=0.0004);与对照组克隆数(465±42)比较,转染组细胞增殖(85±37)明显减少(P<0.05);细胞增殖蛋白PCNA、Cyclin D1及Cyclin E的表达也明显减少(分别为P<0.01、0.05、0.01);结肠癌细胞中METTL3、β-arrestin 1和p-p65蛋白表达均增高(均为P<0.05)。随后HCT116细胞沉默MET-TL3的表达,发现细胞中β-arrestin 1、p-p65蛋白的表达明显下降(均为P<0.05)。结论METTL3影响结肠癌细胞的增殖可能通过β-arrestin 1/p65调控参与肿瘤的发生发展。 展开更多
关键词 结肠癌 N6-甲基腺苷 甲基转移酶样蛋白3 β-抑制蛋白1 核因子κappa B
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An approach to estimate tree height using PolInSAR data constructed by the Sentinel-1 dual-pol SAR data and RVoG model
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作者 Yin Zhang Ding-Feng Duan 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第3期69-79,共11页
We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Se... We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is unavailable.The S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were obtained.The proposed approach was first verified in simulation with satisfactory results.It was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,USA.According to local observations and forest descriptions,the range of estimated tree heights was overall reasonable.Comparing the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is possible.For instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be explored.Also,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season. 展开更多
关键词 Constructed polarimetric Sar data Dual polarization Sentinel-1 Sar data Polarimetric interferometric Sar random volume over the ground model Tree height estimation
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Gravid oviposition sticky trap and dengue non-structural 1 antigen test for early surveillance of dengue in multi-storey dwellings: study protocol of a cluster randomized controlled trial
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作者 Jonathan Wee Kent Liew Sivaneswari Selvarajoo +2 位作者 Wing Tan Rafdzah Ahmad Zaki Indra Vythilingam 《Infectious Diseases of Poverty》 SCIE 2019年第5期71-82,共12页
Background:Dengue is a global disease,transmitted by the Aedes vectors.In 2018,there were 80615 dengue cases with 147 deaths in Malaysia.Currently,the nationwide surveillance programs are dependent on Aedes larval sur... Background:Dengue is a global disease,transmitted by the Aedes vectors.In 2018,there were 80615 dengue cases with 147 deaths in Malaysia.Currently,the nationwide surveillance programs are dependent on Aedes larval surveys and notifications of lab-confirmed human infections.The existing,reactive programs appear to lack sensitivity and proactivity.More efficient dengue vector surveillance/control methods are needed.Methods:A parallel,cluster,randomized controlled,interventional trial is being conducted for 18 months in Damansara Damai,Selangor,Malaysia,to determine the efficacy of using gravid oviposition sticky(GOS)trap and dengue non-structural 1(NS1)antigen test for early surveillance of dengue among Aedes mosquitoes to reduce dengue outbreaks.Eight residential apartments were randomly assigned into intervention and control arms.GOS traps are set at the apartments to collect Aedes weekly,following which dengue NS1 antigen is deteaed in these mosquitoes.When a dengue-positive mosquito is detected,the community will be advised to execute vector search-and-destroy and protective measures.The primary outcome concerns the the percentage change in the(i)number of dengue cases and(ii)durations of dengue outbreaks.Whereas other outcome measures include the change in density threshold of Aedes and changes in dengue-related knowledge,attitude and practice among cluster inhabitants.Discussion:This is a proactive and early dengue surveillance in the mosquito vector that does not rely on notification of dengue cases.Surveillance using the GOS traps should be able to efficiently provide sufficient coverage for multistorey dwellings where population per unit area is likely to be higher.Furthermore,trapping dengue-infected mosquitoes using the GOS trap,helps to halt the dengue transmission carried by the mosquito.It is envisaged that the results of this randomized controlled trial will provide a new proactive,cheap and targeted surveillance tool for the prevention and control of dengue outbreaks.Trial registration:This is a parallel-cluster,randomized controlled,interventional trial,registered at ClinicalTrials.gov(ID:NCT03799237),on 8th January 2019(retrospectively registered). 展开更多
关键词 AEDES Mosquito DENGUE Dengue NS1 test Gravid oviposition sticky trap Cluster randomized controlled trial SURVEILLANCE
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Improved LS+MAR hybrid method to UT1-UTC ultra-short-term prediction by using first-order-difference UT1-UTC
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作者 Fei Ye Yunbin Yuan 《Geodesy and Geodynamics》 EI CSCD 2024年第4期379-385,共7页
Accurate ultra-short-term prediction of the Earth rotation parameters(ERP)holds paramount impor-tance for real-time applications,particularly in reference frame conversion.Among them,diurnal rota-tion(UT1-UTC)which ca... Accurate ultra-short-term prediction of the Earth rotation parameters(ERP)holds paramount impor-tance for real-time applications,particularly in reference frame conversion.Among them,diurnal rota-tion(UT1-UTC)which cannot be directly estimated through Global Navigation Satellite System(GNSS)techniques,significantly affects the rapid and ultra-rapid orbit determination of GNsS satellites.Pres-ently,the traditional LS(least squares)+AR(autoregressive)and LS+MAR(multivariate autoregressive)hybrid methods stand as primary approaches for UT1-UTC ultra-short-term predictions(1-10 days).The LS+MAR hybrid method relies on the UT1-UTC and LOD(length of day)series.However,the correlation between LOD and first-order-difference UT1-UTC is stronger than that between LOD and UT1-UTC.In light of this,and with the aid of the first-order-difference UT1-UTC,we propose an enhanced LS+MAR hybrid method to UT1-UTC ultra-short-term prediction.By using the UT1-UTC and LOD data series of the IERS(International Earth Rotation and Reference Systems Service)EOP 14 C04 product,we conducted a thorough analysis and evaluation of the improved method's prediction performance compared to the traditional LS+AR and LS+MAR hybrid methods.According to the numerical results over more than 210 days,they demonstrate that,when considering the correlation information between the LoD and the first-order-difference UT1-UTC,the mean absolute errors(MAEs)of the improved LS+MAR hybrid method range from 21 to 934μs in 1-10 days predictions.In comparison to the traditional LS+AR hybrid method,the MAEs show a reduction of 7-53μs in 1-10 days predictions,with corresponding improvement percentages ranging from 1 to 28%.Similarly,when compared to the traditional LS+MAR hybrid method,the MAEs have a reduction of 5-42μs in 1-10 days predictions,with corresponding improvement percentages ranging from 4-20%.Additionally,when aided by GNSS-derived LOD data series,the MAEs of improved LS+MAR hybrid method experience further reduction. 展开更多
关键词 UT1-UTCultra-short-termprediction Rapidandultra-rapidproducts LS+ar and LS+Mar CORRELATION First-order-differenceUT1-UTC
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Influence of Angiotensin II on α1-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells
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作者 Itzell Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido +3 位作者 Santiago C. Sigrist-Flores Juan Javier López-Guerrero Enrique Hong Rafael Villalobos-Molina 《Journal of Biosciences and Medicines》 2024年第4期123-134,共12页
Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including func... Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α<sub>1</sub>-adrenergic receptors (α<sub>1</sub>-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10<sup>−5</sup> M), and in some experiments, 5-Methylurapidil (α<sub>1A</sub>-AR antagonist), AH11110A (α<sub>1B</sub>-AR antagonist), or BMY-7378 (α<sub>1D</sub>-AR antagonist), were used to identify the α<sub>1</sub>-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α<sub>1D</sub>-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α<sub>1</sub>-ARs proteins were evaluated. α<sub>1D</sub>-AR increased at 30 and 60 min post Ang II exposure, the α<sub>1A</sub>-AR diminished from 1 to 4 h, while α<sub>1B</sub>-AR remained unchanged over 24 h of Ang II exposure. Ang II induced an increase of α<sub>1D</sub>-AR at short times, and BMY-7378 protected α<sub>1D</sub>-AR from desensitization. 展开更多
关键词 Angiotensin II α1D-ar α1-ar Expression Rat aorta Smooth Muscle Cells
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血清c5ar1、ALP及25(OH)D3的表达规律对股骨颈骨折术后骨折愈合情况的预测价值
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作者 王义冬 《四川生理科学杂志》 2024年第3期606-609,共4页
目的:探讨血清补体成分5a受体1(Complement component 5a receptor,c5ar1)、碱性磷酸酶(Alkaline phosphatase,ALP)及25羟基维生素D(Vitamin D325-hydroxy monohydrate,25(OH)D3)的表达规律对股骨颈骨折术后骨折愈合情况的预测价值.方法... 目的:探讨血清补体成分5a受体1(Complement component 5a receptor,c5ar1)、碱性磷酸酶(Alkaline phosphatase,ALP)及25羟基维生素D(Vitamin D325-hydroxy monohydrate,25(OH)D3)的表达规律对股骨颈骨折术后骨折愈合情况的预测价值.方法:选取2019年1月至2022年12月本院治疗的股骨颈发生骨折且实施全髋关节置换术的98例患者作为研究对象.依据其术后6 m的影像学方面检查结果评估患者的骨折愈合情况,并将患者分成骨折愈合组(77例)和未愈合组(21例).于入院及术后42 d分别对两组的血清c5ar1、ALP、25(OH)D3水平进行测定,采用Pearson相关性分析c5ar1、ALP、25(OH)D3的相关性.采用受试者工作(Receiver operating characteristic,ROC)曲线分析血清c5ar1、ALP及25(OH)D3对股骨颈骨折术后骨折的愈合情况的预测价值.结果:骨折愈合组术后血清c5ar1、ALP及25(OH)D3的表达水平均高于术前(P<0.05),未愈合组术后血清c5ar1、ALP及25(OH)D3的表达水平均低于术前(P<0.05);Pearson相关性分析结果显示,c5ar1与25(OH)D3呈正相关关系(P<0.05);c5ar1、ALP、25(OH)D3诊断股骨颈骨折术后骨折愈合情况的敏感度分别为92.20%、62.30%、76.60%,特异度分别为90.50%、47.60%、52.40%,ROC曲线分析显示,c5ar1、ALP、25(OH)D3诊断股骨颈骨折术后骨折愈合情况的曲线下面积(area under curve,AUC)分别为0.953、0.515、0.765.结论:血清c5ar1、ALP及25(OH)D3的表达水平升高可促进股骨颈骨折术后骨折愈合,c5ar1与25(OH)D3呈正相关关系,c5ar1、25(OH)D3诊断股骨颈骨折术后骨折愈合情况具有较高的准确性,而ALP预测股骨颈骨折术后骨折愈合情况的准确性较低. 展开更多
关键词 c5ar1 ALP 25(OH)D3 股骨颈骨折 术后骨折愈合
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WT-1、AR和Ki-67在睾丸穿刺活检组织病理诊断中的应用 被引量:6
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作者 吴惠 孟宇宏 +4 位作者 路平 宁浩勇 洪柳 康筱玲 段敏刚 《临床与实验病理学杂志》 CAS CSCD 北大核心 2015年第8期846-849,共4页
目的探讨睾丸穿刺活检标本中Sertoli细胞和生精细胞的特异性标志物。方法选取3例经病理诊断为前列腺腺癌行去势治疗的正常睾丸组织及15例临床诊断为无精症的睾丸穿刺活检组织,采用免疫组化En Vision两步法检测WT-1、AR和Ki-67的表达。... 目的探讨睾丸穿刺活检标本中Sertoli细胞和生精细胞的特异性标志物。方法选取3例经病理诊断为前列腺腺癌行去势治疗的正常睾丸组织及15例临床诊断为无精症的睾丸穿刺活检组织,采用免疫组化En Vision两步法检测WT-1、AR和Ki-67的表达。结果免疫组化染色显示WT-1和AR在3例正常睾丸组织和15例睾丸穿刺活检组织曲细精管内的Sertoli细胞胞核均呈棕黄色,阳性率均为100%,生精细胞胞核的阳性率为0。15例睾丸活检组织中生精细胞的Ki-67阳性率为100%。结论 WT-1、AR和Ki-67可做为睾丸穿刺活检组织中Sertoli细胞和生精细胞的特异性标志物,为睾丸穿刺活检的病理诊断提供依据。 展开更多
关键词 睾丸穿刺活检 SERTOLI细胞 WT-1 ar KI-67
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