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Application of the extended Fourier amplitude sensitivity testing(FAST)method to inflated,axial stretched,and residually stressed cylinders 被引量:1
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作者 H.ASGHARI H.TOPOL +1 位作者 B.MARKERT J.MERODIO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2139-2162,共24页
This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafuncti... This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafunctions and the Ishigami function are considered in the sensitivity analysis(SA).The effects of the input variables on the output variables are investigated,and the most important parameters of the system under the applied pressure and axial force such as the axial stretch and the azimuthal stretch are determined. 展开更多
关键词 sensitivity analysis(SA) Fourier amplitude sensitivity test(FAST)method cylindrical inflation nonlinear elasticity
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Tumour chemotherapy sensitivity test may predict clinical outcomes in colorectal cancer patients receiving oxaliplatin and fluoropyrimidine-based regimens
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作者 Si-Jia Li Yi-Xuan Lu +3 位作者 Fang-Yue Zheng Yi-Cong Bian Li-Yan Miao Chen-Rong Huang 《World Journal of Gastrointestinal Oncology》 2025年第11期141-152,共12页
BACKGROUND Chemotherapy is an essential treatment for colorectal cancer(CRC)patients after surgery,but many patients do not benefit from chemotherapy because tumour heterogeneity results in varied responses.AIM To stu... BACKGROUND Chemotherapy is an essential treatment for colorectal cancer(CRC)patients after surgery,but many patients do not benefit from chemotherapy because tumour heterogeneity results in varied responses.AIM To study the effectiveness of in vitro chemosensitivity tests adenosine tripho-sphate-based tumour chemotherapy sensitivity test(ATP-TCA)for tailoring po-stoperative chemotherapy regimens for patients with CRC.METHODS Between January 2015 to December 2021,a total of 1549 CRC patients underwent surgery and in vitro chemosensitivity testing using ATP-TCA.A subset of 405 patients who met the survival assessment criteria were followed to collect data on overall survival(OS)and disease-free survival(DFS).Cox regression analysis revealed independent prognostic factors that affect OS and DFS for those re-ceiving oxaliplatin(L-OPH)and fluoropyrimidine-based regimens,aiding in the development of clinical predictive models.The relationships between the ATP-TCA results and clinical outcomes were analysed using the Kaplan-Meier method.RESULTS Tumour heterogeneity and resistance to multiple drugs were observed in 1549 patients.The sensitivity to 5-fluorouracil(5-FU)combined with L-OPH was tested among 1474 of these patients,yielding a sensitivity rate of 11.9%.ATP-TCA results were identified as an independent prognostic factor for DFS[P=0.002,hazard ratio(95%confidence interval):4.98(1.81-13.72)]in patients with resectable CRC.Compared with drug-resistant patients,sensitive CRC patients treated with 5-FU and L-OPH had significantly prolonged DFS(P=0.027).Further Kaplan-Meier analysis indicated that ATP-TCA sensitivity was significantly associated with improved OS(P=0.048)and DFS(P=0.003)in patients with stage III CRC.CONCLUSION The response of CRC patients to the combination regimen of 5-FU and L-OPH is heterogeneous.This study confirmed that the ATP-TCA is a valuable tool for predicting clinical outcomes,such as DFS,in patients with resectable CRC receiving chemotherapy.Although further validation with multicentre data is still necessary,these findings support that the ATP-TCA may function as a guiding tool for personalized chemotherapy administration,thereby optimizing treatment opportunities for patients. 展开更多
关键词 Colorectal cancer Precision oncology Adenosine triphosphate-based tumour chemotherapy sensitivity test Clinical prediction model CHEMOSENSITIVITY 5-fluorouracil OXALIPLATIN
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Patient-derived organoids in hepatobiliary pancreatic cancer research:Their uses and limitations
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作者 Sam Jacobs William Butterworth Ewen A Griffiths 《World Journal of Gastroenterology》 2025年第36期162-165,共4页
In this letter,we discuss the highlights of the paper by Hu et al,including how patient-derived organoids may be beneficial to hepatobiliary pancreatic research.The article provides a review of how organoids can be us... In this letter,we discuss the highlights of the paper by Hu et al,including how patient-derived organoids may be beneficial to hepatobiliary pancreatic research.The article provides a review of how organoids can be used in drug sensitivity testing;looking at ways in which successful organoids are created.The literature included in the review revealed heterogeneity in organoid establishment inclu-ding some differences between organoids from resected tumours compared with liquid biopsies.Additional research is required in creating organoids from liquid biopsies and optimizing these techniques for widespread clinical practice.The article raises awareness of limitations of organoids with suggestions of how co-culture or microfluid platforms may help to simulate the tumour microenvir-onment for better model fidelity.The article provides a comprehensive review of how organoids are being used in drug testing and ideas about how to harvest or produce these in future. 展开更多
关键词 Patient-derived organoids Organ-on-a-chip Sensitivity testing CO-CULTURES Tumour microenvironment
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Ensemble source apportionment of particulate matter and volatile organic compounds and quantifying ensemble source impacts on ozone
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作者 Weiqing Liang Zhenyu Wang +4 位作者 Dongheng Zhao Jinxing Liu Tong Ma Yinchang Feng Guoliang Shi 《Journal of Environmental Sciences》 2025年第11期534-545,共12页
Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pol... Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pollution,exploring the common sources of PM_(2.5) and VOCs is essential.However,previous researches most carried out either PM_(2.5) or VOCs source appointment.In this study,we applied the ensemble source apportionment method to explore the impacts of common sources on PM_(2.5)-VOCs.Subsequently,we obtained the ensemble source impacts on O_(3) combining the extracted VOCs source profile and ozone formation potential.We found that the focus of environmentalmanagement and source control should be varied accordingly for different pollutants.Vehicle emission was the largest contributor(41%)to PM_(2.5)-VOCs,while industrial emission was the main common source(51%)to O_(3).The result showed that the O_(3) production rate is not only related to the VOCs emission,but also to the reactivity of VOCs.In addition,sensitivity tests revealed that temperature was the main factor affecting O_(3) formation.The study provides a framework to explore the common sources impact on PM_(2.5) and VOCs,which is benefit to address both PM_(2.5) and O_(3) mitigations. 展开更多
关键词 Ensemble source apportionment Particulate matter Volatile organic compounds OZONE Sensitivity test
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Integrating network pharmacology and experimental validation to uncover the synergistic effects of Huangqi (Radix Astragali Mongolici)-Ezhu (Rhizoma Curcumae Phaeocaulis)with 5-fluorouracil in colorectal cancer models
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作者 TAN Xiying GU Ruxin +5 位作者 TAO Jing ZHANG Yu SUN RuiQian YIN Gang ZHANG Shuo TANG Decai 《Journal of Traditional Chinese Medicine》 2025年第2期385-398,共14页
OBJECTIVE:To evaluate the effects of Huangqi(Radix Astragali Mongolici)-Ezhu(Rhizoma Curcumae Phaeocaulis)(HQEZ)on colorectal cancer therapies and to elucidate the potential mechanisms of HQEZ,especially in combinatio... OBJECTIVE:To evaluate the effects of Huangqi(Radix Astragali Mongolici)-Ezhu(Rhizoma Curcumae Phaeocaulis)(HQEZ)on colorectal cancer therapies and to elucidate the potential mechanisms of HQEZ,especially in combination with 5-Fluorouracil(5-FU).METHODS:The anti-tumor effects of HQEZ were evaluated in colorectal cancer models both in vivo and in vitro.The network pharmacological assay was used to investigate potential mechanisms of HQEZ.Potential target genes were selected by Gene Ontology(GO)enrichment analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis,protein-protein interaction network(PPI)and molecular docking.Within key targets,potential targets related to drug sensitivity,especially the sensitivity to 5-FU,were evaluated in HCT116 in vitro by immunofluorescence,quantitative real-time polymerase chain reaction(qPCR)and Western-blot.Then,changes in potential targets were assessed in tumors from tumor-bearing mice and the expression of these targets was also evaluated in colorectal cancer(COAD)patients from the Cancer Genome Atlas Program(TCGA)database.RESULTS:HQEZ significantly enhanced the anti-tumor activity of 5-FU in vivo and inhibit the growth of HCT116 in vitro.By network pharmacological analysis,key targets,such as protein kinase B(AKT1),epidermal growth factor receptor(EGFR),adenosine triphosphate(ATP)binding cassette subfamily B member 1(ABCB1,also named multidrug resistance protein 1,MDR1),ATP binding cassette subfamily G member 2(ABCG2),thymidylate synthetase(TYMS,also named TS),prostaglandinendoperoxide synthase 2(PTGS2),matrix metallopeptidase 2(MMP2),MMP9,toll like receptor 4(TLR4),TLR9 and dihydropyrimidine dehydrogenase(DPYD),were identified.Additionally,4 potential core active ingredients(Folate,Curcumin,quercetin and kaempferol)were identified to be important for the treatment of colorectal cancer with HQEZ.In key targets,chemoresistance related targets were validated to be affected by HQEZ.Furthermore,5-FU sensitivity related targets,including MDR1,TS,EGFR,ribonucleotide reductase catalytic subunit M1,Breast and Ovarian Cancer Susceptibility Protein 1(BRCA1)and mutl homolog 1 were also significantly reduced by HQEZ both in vitro and in vivo.Finally,these validated key targets and 5-FU sensitivity related targets were demonstrated to be up-regulated in COAD patients based on TCGA database.CONCLUSION:HQEZ has synergistic effects on the antitumor activity of 5-FU in the treatment of colorectal cancer both in vivo and in vitro.The beneficial effect of HQEZ results from the inhibition of the drug sensitivity targets associated with 5-FU.The combination therapy of HQEZ with 5-FU or other chemotherapeutic drugs will also improve the anti-tumor efficacy of chemotherapy. 展开更多
关键词 fluorouracil parasitic sensitivity tests colorectal neoplasms network pharmacology Huangqi(Radix Astragali Mongolici)-Ezhu(Rhizoma Curcumae Phaeocaulis)
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Screening and Efficacy Observation of Traditional Chinese Medicine Against Chicken Pathogenic Escherichia coli 被引量:18
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作者 庞向红 褚秀玲 +3 位作者 苏建青 梁淑珍 李全福 胡满 《Agricultural Science & Technology》 CAS 2009年第1期140-144,共5页
[ Objective] The aim of this study was to lay a foundation for obtaining effective traditional Chinese medicine preparations controlling chicken colibacillosis. [ Method] With the western medicine Lomeflbxacin Hydroch... [ Objective] The aim of this study was to lay a foundation for obtaining effective traditional Chinese medicine preparations controlling chicken colibacillosis. [ Method] With the western medicine Lomeflbxacin Hydrochloride and Sodium Chloride Injection as the control, drug sensitivity tests of 15 single traditional Chinese herbs and seven self-made Chinese herbal compounds were conducted. Subsequently, the single traditional Chinese herbs presenting good in vitro antibacterial effects against Escherichia coli and all the seven compounds were given to the chicks artificially infected with E. coil to observe their efficacies. [ Result] The results of drug sensitivity tests showed that all the 15 traditional Chinese herbs had certain antibacterial effect against E. coli, among which aloe, pomegranate rind and radix sanguisorbae were the best. Compound 1, 2 and 5 had good antibacterial effects in vitro. By in vivo test, traditional Chinese medicines showed superior efficacies on infected chicks than western medicine, and compound 1 and 2 performed well. [ConclusiOn] Traditional Chinese medicine preparations are good at controlling Chicken colibacillosis, but their bacteriostasis mechanism in vivo was different with that in vitro. 展开更多
关键词 Traditional Chinese medicine preparation Drug sensitivity test Chicken colibacillosis In vivo test
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Test and Study of the Rock Pressure Sensitivity for KeLa-2 Gas Reservoir in the Tarim Basin 被引量:1
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作者 杨胜来 王小强 +1 位作者 冯积累 苏应献 《Petroleum Science》 SCIE CAS CSCD 2004年第4期11-16,46,共7页
KeLa-2 gas reservoir is the largest uncompartimentalized gas field so far discovered in China, with a reserve of hundreds of billions of cubic meters of dry gas. It has such features as extremely long interval (550m)... KeLa-2 gas reservoir is the largest uncompartimentalized gas field so far discovered in China, with a reserve of hundreds of billions of cubic meters of dry gas. It has such features as extremely long interval (550m), high pressure (74.5MPa) and pressure coefficient (2.022). Gas reservoirs with a pressure coefficient of over 2.0 are not commonly found. The abnormal high-pressure reservoirs are quite different in characteristic and performance during the process of depletion exploitation. Therefore, it is necessary to know the property of pressure sensitivity for this abnormal high-pressure reservoir. The aim of this paper is to test the reservoir pressure sensitivity and to analyze its effect on the deliverability of gas. Through some experiments, the permeability change with the confining pressure of rock samples from KeLa-2 abnormal high-pressure gas reservoir is measured. A power function is used to match the measured data, and to derive an empirical equation to describe the change of permeability through the change of the reservoir pressure or effective overburden pressure. Considering the permeability change during the development of reservoirs, a conventional deliverability equation is modified, and the deliverability curve for KeLa-2 gas reservoir is predicted. The research indicates that the extent of the pressure sensitivity of rock samples from KeLa-2 is higher than that from the Daqing oilfield. KeLa-2 reservoir rock has the feature of an undercompaction state. The pressure sensitivity of a reservoir may decrease the well deliverability. It is concluded that for KeLa-2 reservoir the predicted absolute open flow (AOF), when the pressure sensitivity is taken into account, is approximately 70% of the AOF when permeability is constant and does not change with pressure. 展开更多
关键词 Abnormal high-pressure reservoir pressure sensitivity test PERMEABILITY deliverability
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Percentiles Estimation for a Response Distribution 被引量:1
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作者 田玉斌 牟可典 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期424-428,共5页
To estimate percentiles of a response distribution, the transformed response rule of Wetherill and Robbins-Monro sequential design were proposed under Log-Logistic model. Based on responses data, a necessary and suffi... To estimate percentiles of a response distribution, the transformed response rule of Wetherill and Robbins-Monro sequential design were proposed under Log-Logistic model. Based on responses data, a necessary and sufficient condition for the existence of maximum likelihood estimators and then the calculating formula were presented. After a simulation study, the proposed approach was applied to 65# detonator. Numerical results showed that estimators of percentiles from the proposed approach are robust to the parametric models lacking information on the original response distribution. 展开更多
关键词 PERCENTILES maximum likelihood estimator sensitivity test transformed response
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New System to Measure the Yaw and PitchAngles of Rocket in Launch Phase
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作者 王志军 王瑞臣 +1 位作者 王辉 蔡汉文 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期73-77,共5页
Aim To describe a news system for measuring the and pitch angles of rocket during the launch phase Methods Optical system was to reflect the spot that represents the angular movement of rocket to the position sensitiv... Aim To describe a news system for measuring the and pitch angles of rocket during the launch phase Methods Optical system was to reflect the spot that represents the angular movement of rocket to the position sensitive detector that can convert analogue signal into digital one.Results Compared with conventional optical lever test system which had been applied to measure rocket attitude angle,the new system used the position sensitive detector to replace the screen and high-speed photographic instrumentation as grapher,which can avert photointerpretive data reduction and apply to field experiment more easily and pre- cisely .Conclusion Experimental results show that the test system can be used in measuring the yaw and pitch angles of rocket effectively. 展开更多
关键词 ROCKETS attitude angle position sensitive detector test system
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Diagnosis and Treatment of Hemorrhagic Pneumonia of Mink 被引量:4
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作者 张贵贤 项方 +1 位作者 王殿永 李国华 《Agricultural Science & Technology》 CAS 2012年第12期2560-2561,2666,共3页
[Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materi... [Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materials. It was necropsied, and its tissues such as liver, kidney, spleen and lung were taken under aseptic condition, then inoculated into general nutrition agar and blood agar. The bacteria were isolated and purified, and the strains obtained were carried out animal inoculation test and drug sensitivity test. Finally, the relevant treatment and preven- tive measures were put forward. [Conclusion] The bacteria isolated were detected to be negative by Gram staining; it formed hemolysis ring in blood agar; the bacteria could ferment glucose and xylose, which could not ferment sucrose, lactose, maltose and esculin; it was positive in catalase and oxidase test, and negative in urease test and hydrogen sulfide test; so the strain was indentified to be Pseudomonas aerugi- nosa. Drug sensitivity test showed that the bacteria were highly sensitive to ciprofloxacin, which had tolerance to cefoxitin. [Conclusion] The study laid foundation for diagnosis and treatment of hemorrhagic pneumonia of mink. 展开更多
关键词 MINK Pseudomonas aeruginosa Drug sensitivity test
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Simulations of a Hydrological Model as Coupled to a Regional Climate Model 被引量:8
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作者 曾新民 赵鸣 +4 位作者 苏炳凯 汤剑平 郑益群 桂祁军 周祖刚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第2期227-236,共10页
Considering a detailed hydrologic model in the land surface scheme helps to improve the simulation of regional hydro-climatology. A hydrologic model, which includes spatial heterogeneities in precipitation and infiltr... Considering a detailed hydrologic model in the land surface scheme helps to improve the simulation of regional hydro-climatology. A hydrologic model, which includes spatial heterogeneities in precipitation and infiltration, is constructed and incorporated into the land surface scheme BATS. Via the coupled-model (i.e., a regional climate model) simulations, the following major conclusions are obtained: the simulation of surface hydrology is sensitive to the inclusion of heterogeneities in precipitation and infiltration; the runoff ratio is increased after considering the infiltration heterogeneity, a result which is more consistent with the observations of surface moisture balance over humid areas; the introduction of the parameterization of infiltration heterogeneity can have a greater influence on the regional hydro-climatology than the precipitation heterogeneity; and the consideration of the impermeable fraction for the region reveals some features that are closer to the trend of aridification over northern China. 展开更多
关键词 hydrological model spatial heterogeneity moisture balance regional climate sensitivity test
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Attempts to enhance the eradication rate of helicobacter pylori infection 被引量:9
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作者 Chang Seok Bang Gwang Ho Baik 《World Journal of Gastroenterology》 SCIE CAS 2014年第18期5252-5262,共11页
Increasing rates of antimicrobial resistance to clarithromycin and metronidazole present challenges in maintaining optimal eradication rates.Knowledge of local antibiotic resistance and consumption pattern is importan... Increasing rates of antimicrobial resistance to clarithromycin and metronidazole present challenges in maintaining optimal eradication rates.Knowledge of local antibiotic resistance and consumption pattern is important in selecting a reliable regimen.In addition,adverse effect profiles of therapeutic regimens are important and must be addressed to enhance compliance rates.Various methods of enhancing the eradication rates of Helicobacter pylori(H.pylori)have been investigated,including changing combinations or durations of established drugs,adding adjuvant drugs,or development of new molecules or agents.Bismuth-containing quadruple,sequential,concomitant,and levofloxacin-based triple therapies are replacing the long-standing standard of the triple regimen.Despite the encouraging results of these regimens,individualized approaches like treatment after antibiotics resistance test or CYP2C19genotyping would be the mainstream of future therapy.Because scientific,economic,and technical problems make these advance therapies unfit for widespread use,future development for H.pylori therapy should be directed to overcome individualized antibiotic resistance.Although various novel regimens and additive agents have indicated favorable outcomes,more studies or validations are needed to become a mainstream H.pylori therapy. 展开更多
关键词 Helicobacter pylori Antimicrobial drug resistance CLARITHROMYCIN METRONIDAZOLE Microbial sensitivity tests
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Using a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to Study the Sensitivity of Land Surface and Boundary Layer Processes to Soil and Vegetation Conditions 被引量:7
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作者 刘树华 乐旭 +1 位作者 刘辉志 胡非 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第5期717-729,共13页
A series of sensitivity tests are performed to test the stability and sensibility of the Modified Soil-Plant-Atmosphere Scheme (MSPAS), which was wholly introduced in a previous paper. The numerical simulation results... A series of sensitivity tests are performed to test the stability and sensibility of the Modified Soil-Plant-Atmosphere Scheme (MSPAS), which was wholly introduced in a previous paper. The numerical simulation results from the experiments show good agreement with physical reality. Besides, some of the results are illuminating. Together with the first paper, it is concluded that MSPAS is a simple but effective model, and it is practically valuable in the research work of desertification control and reforestation in China. 展开更多
关键词 Modified Soil-Plant-Atmosphere Scheme DESERTIFICATION sensitivity test
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The Coordinated Influence of Indian Ocean Sea Surface Temperature and Arctic Sea Ice on Anomalous Northeast China Cold Vortex Activities with Different Paths during Late Summer 被引量:5
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作者 Yitong LIN Yihe FANG +3 位作者 Chunyu ZHAO Zhiqiang GONG Siqi YANG Yiqiu YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期62-77,共16页
The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NC... The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NCCV intensity with atmospheric circulations in late summer,the sea surface temperature(SST),and Arctic sea ice concentration(SIC)in the preceding months,are analyzed.The sensitivity tests by the Community Atmosphere Model version 5.3(CAM5.3)are used to verify the statistical results.The results show that the coordination pattern of East Asia-Pacific(EAP)and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode(NIOD)during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV.While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer-which is forced by SST anomalies in the South Indian Ocean dipole mode(SIOD)in the preceding June and SIC anomalies in the Barents Sea in the preceding April-causes the intensity anomaly of the second type.The third type is atypical and is not analyzed in detail.Sensitivity tests,jointly forced by the SST and SIC in the preceding period,can well reproduce the observations.In contrast,the results forced separately by the SST and SIC are poor,indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months. 展开更多
关键词 machine learning method Northeast China cold vortex path classification Indian Ocean sea surface temperature Arctic sea ice model sensitivity test
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Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori 被引量:4
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作者 Xiao-Feng Luo Jian-Hua Jiao +5 位作者 Wen-Yue Zhang Han-Ming Pu Bao-Jin Qu Bing-Ya Yang Min Hou Min-Jun Ji 《World Journal of Gastroenterology》 SCIE CAS 2016年第25期5822-5830,共9页
AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23 Sr RNA gene in Helicobacter pylori(H. pylori) by nested-allele specific primer-polymerase chain reaction(nested-ASP-PCR).METHODS: T... AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23 Sr RNA gene in Helicobacter pylori(H. pylori) by nested-allele specific primer-polymerase chain reaction(nested-ASP-PCR).METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test(RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nestedASP-PCR, bacterial culture and disk diffusion. RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23 SrR NA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates thanASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87(87.88%) and 67(67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin. CONCLUSION: The nested-ASP-PCR assay showed higher detection sensitivity than ASP-PCR and drug sensitivity testing, which could be performed to evaluate clarithromycin resistance of H. pylori. 展开更多
关键词 Helicobacter pylori Nested-allele specific primer-polymerase chain reaction Rapid urease test Clarithromycin resistance Drug sensitivity testing
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Numerical simulation based on two-directional freeze and thaw algorithm for thermal diffusion model 被引量:5
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作者 Junqiang GAO Zhenghui XIE +1 位作者 Aiwen WANG Zhendong LUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第11期1467-1478,共12页
Freeze-thaw processes significantly modulate hydraulic and thermal char- acteristics of soil. The changes in the frost and thaw fronts (FTFs) affect the water and energy cycles between the land surface and the atmos... Freeze-thaw processes significantly modulate hydraulic and thermal char- acteristics of soil. The changes in the frost and thaw fronts (FTFs) affect the water and energy cycles between the land surface and the atmosphere. Thus, the frozen soil com- prising permafrost and seasonally frozen soil has important effects on the land surface hydrology in cold regions. In this study, a two-directional freeze and thaw algorithm is incorporated into a thermal diffusion equation for simulating FTFs. A local adaptive variable-grid method is used to discretize the model. Sensitivity tests demonstrate that the method is stable and FTFs can be tracked continuously. The FTFs and soil tempera- ture at the Qinghai-Tibet Plateau D66 site are simulated hourly from September 1, 1997 to September 22, 1998. The results show that the incorporated model performs much better in the soil temperature simulation than the original thermal diffusion equation, showing potential applications of the method in land-surface process modeling. 展开更多
关键词 freeze and thaw algorithm frost and thaw front (FTF) sensitivity test thermal diffusion equation
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Relationship between Mutation of IR in the mtr System of Neisseria Gonorrhoeae and Multiple Antibiotic Resistance 被引量:2
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作者 张丽霞 林能兴 +3 位作者 黄长征 陈宏翔 林云 涂亚庭 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第2期248-250,共3页
To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and its multiple antibiotic resistance, minimal i... To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and its multiple antibiotic resistance, minimal inhibitory concentrations (MICs) for the clinically isolated strains were tested by agar-dilution-method. The mtr system's IR gene of NG was sequenced after amplification by polymerase chain reaction (PCR). Either two susceptive or five penicillin-resistant strains had no base mutation in IR gene, while all of the 13 strains with multiple-antibiotic-resistance had a singlebase deletion (A/T). The result suggests that a single-base deletion of the thirteen-base IR sequence in mtr system of NG might result in multiple antibiotic resistance but is not associated with single antibiotic resistance. 展开更多
关键词 Neisseria gonorrhoeae gene mutation inverted repeat sequence antimicrobial sensitivity tests
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Study on Possible Mechanism of Terrain Influence on Cold-flow Snowstorm 被引量:2
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作者 ZHOU Xue-song YANG Cheng-fang ZHANG Shao-lin 《Meteorological and Environmental Research》 CAS 2011年第8期48-51,85,共5页
[Objective] The research aimed to study the possible mechanism of terrain effect on cold-flow snowstorm.[Method] By using the meso-scale numerical model(WRF),a cold-flow snowstorm weather process in Shandong Peninsula... [Objective] The research aimed to study the possible mechanism of terrain effect on cold-flow snowstorm.[Method] By using the meso-scale numerical model(WRF),a cold-flow snowstorm weather process in Shandong Peninsula was carried out numerical simulation and terrain sensitivity contrast test.The possible reason of terrain effect on falling zone and strength of snowstorm was deeply analyzed from water vapor,thermodynamic field and so on.[Result] The mountain terrain in Shandong Peninsula had great influences on falling zone and strength of cold-flow snowstorm.The strength of snowstorm obviously increased,and the snowfall center obviously moved northward.The main reason was that terrain caused the low-level wind field convergence and vertical movement in the troposphere strengthened.Then,the spatial distribution of water vapor and snow water content in the cold-flow snowstorm process obviously changed.So,the whole snowstorm process was affected.[Conclusion] The mountain terrain in Shandong Peninsula was the important element which needed to be focused on considering in the forecast analysis of cold-flow snowstorm weather process. 展开更多
关键词 Cold-flow snowstorm Mountain terrain Numerical sensitivity test Influence mechanism China
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An Improvement of the Mass Flux Convection Parameterization Scheme and its Sensitivity Tests for Seasonal Prediction over China 被引量:1
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作者 平凡 高守亭 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第6期978-990,共13页
A modified cumulus parameterization scheme, suitable for use in a seasonal forecast model, is presented. This parameterization scheme is an improvement of the mass flux convection scheme developed by Gregory and Rownt... A modified cumulus parameterization scheme, suitable for use in a seasonal forecast model, is presented. This parameterization scheme is an improvement of the mass flux convection scheme developed by Gregory and Rowntree (1989; 1990). This convection scheme uses a 'bulk' cloud model to present an ensemble of convective clouds, and aims to represent shallow, deep, and mid-level convection. At present, this convection scheme is employed in the NCC T63L20 model (National Climate Center, China Meteorological Administration). Simulation results with this scheme have revealed some deficiencies in the scheme, although to some extent, it improves the accuracy of the simulation. In order to alleviate the deficiencies and reflect the effect of cumulus convection in the actual atmosphere, the scheme is modified and improved. The improvements include (i) the full estimation of the effects of the large-scale convergence in the lower layer upon cumulus convection, (ii) the revision of the initial convective mass flux, and (iii) the regulation of convective-scale downdrafts. A comparison of the results obtained by using the original model and the modified one shows that the improvement and modification of the original convection scheme is successful in simulating the precipitation and general circulation field, because the modified scheme provides a good simulation of the main features of seasonal precipitation in China, and an analysis of the anomaly correlation coefficient between the simulation and the observations confirms the improved results. 展开更多
关键词 cumulus convection parameterization scheme convection heating and moistening numerical simulation sensitivity test
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Distribution of pathogenic bacteria and antimicrobial sensitivity of eye infections in Suzhou 被引量:1
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作者 Li Zhang Hai-Zhang You +4 位作者 Guo-Hui Wang Wei Xu Jian-Shan Li Qing-Liang Zhao Shu Du 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期700-706,共7页
AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collecte... AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections. 展开更多
关键词 eye infection pathogenic bacteria drug resistance antimicrobial sensitivity test
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