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Characterization of chemical composition of high viscosity heavy oils:Macroscopic properties, and semi-quantitative analysis of molecular composition using high-resolution mass spectrometry
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作者 Jian-Xun Wu Shuo-Fan Li +6 位作者 Qi-Fu Li Feng Yan Qi-Lin Zhou Shuai Ma Ya-He Zhang Suo-Qi Zhao Quan Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3612-3620,共9页
Heavy oil is an important resource in current petroleum exploitation, and the chemical composition information of heavy oil is crucial for revealing its viscosity-inducing mechanism and solving practical exploitation ... Heavy oil is an important resource in current petroleum exploitation, and the chemical composition information of heavy oil is crucial for revealing its viscosity-inducing mechanism and solving practical exploitation issues. In this study, the techniques of high-temperature gas chromatography and high-resolution mass spectrometry equipped with an electrospray ionization source were applied to reveal the chemical composition of typical heavy oils from western, central, and eastern China. The results indicate that these heavy oils display significant variations in their bulk properties, with initial boiling points all above 200℃. Utilizing pre-treatment and ESI high-resolution mass spectrometry, an analysis of the molecular composition of saturated hydrocarbons, aromatic hydrocarbons, acidic oxygen compounds, sulfur compounds, basic nitrogen compounds, and neutral nitrogen compounds within the heavy oil was conducted. Ultimately, a semi-quantitative analysis of the molecular composition of the heavy oil was achieved by integrating the elemental content. The semi-quantitative analysis results of Shengli-J8 heavy oil and a conventional Shengli crude oil show that Shengli-J8 heavy oil lacks alkanes and low molecular weight aromatic hydrocarbons, which contributes to its high viscosity. Additionally,characteristic molecular sets for different heavy oils were identified based on the semi-quantitative analysis of molecular composition. The semi-quantitative analysis of molecular composition in heavy oils may provide valuable reference data for establishing theoretical models on the viscosity-inducing mechanism in heavy oils and designing viscosity-reducing agents for heavy oil exploitation. 展开更多
关键词 Heavy oil HRMS Molecular composition semi-quantitative analysis VISCOSITY
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Garg incontinence scores: New scoring system on the horizon to evaluate fecal incontinence. Will it make a difference?
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作者 Petr Tsarkov Inna Tulina +2 位作者 Parvez Sheikh Darya D Shlyk Pankaj Garg 《World Journal of Gastroenterology》 SCIE CAS 2024年第3期204-210,共7页
The main aim of this opinion review is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593–4603.The authors in the published article developed a new scoring ... The main aim of this opinion review is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593–4603.The authors in the published article developed a new scoring system,Garg incon-tinence scores(GIS),for fecal incontinence(FI).FI is a chronic debilitating disease that has a severe negative impact on the quality of life of the patients.Rome IV criteria define FI as multiple episodes of solid or liquid stool passed into the clothes at least twice a month.The associated social stigmatization often leads to significant under-reporting of the condition,which further impairs management.An important point is that the complexity and vagueness of the disease make it difficult for the patients to properly define and report the magnitude of the problem to their physicians.Due to this,the management becomes even more difficult.This issue is resolved up to a considerable extent by a scoring ques-tionnaire.There were several scoring systems in use for the last three decades.The prominent of them were the Cleveland Clinic scoring system or the Wexner scoring system,St.Marks Hospital or Vaizey’s scores,and the FI severity index.However,there were several shortcomings in these scoring systems.In the opinion review,we tried to analyze the strength of GIS and compare it to the existing scoring systems.The main pitfalls in the existing scoring systems were that most of them gave equal weightage to different types of FI(solid,liquid,flatus,etc.),were not comprehensive,and took only the surgeon’s perception of FI into view.In GIS,almost all shortcomings of previous scoring systems had been addressed:different weights were assigned to different types of FI by a robust statistical methodology;the scoring system was made comprehensive by including all types of FI that were previously omitted(urge,stress and mucus FI)and gave priority to patients’rather than the physicians’perceptions while developing the scoring system.Due to this,GIS indeed looked like a paradigm shift in the evaluation of FI.However,it is too early to conclude this,as GIS needs to be validated for accuracy and simplicity in future studies. 展开更多
关键词 Fecal incontinence scoring system URGE Stress Flatus
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Comparison of different severity scores in correlating hemoglobin levels with the severity of hepatic decompensation: An observational study
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作者 Himayat Ullah Sarwat Huma +13 位作者 Ghulam Yasin Muhammad Ashraf Nafisa Tahir Qazi Tahir Uddin Hossam Shabana Mostafa A R Hussein Abdulrahman Shalaby Mohammad Mossaad Alsayyad Ashraf Said Ali Farahat Hani Ismail Hamed Hazem Sayed Ahmed Ayoub Mohammed S Imam Essam Elmahdi 《World Journal of Hepatology》 2025年第1期55-63,共9页
BACKGROUND Chronic liver disease is a growing global health problem,leading to hepatic decompensation characterized by an array of clinical and biochemical complic-ations.Several scoring systems have been introduced i... BACKGROUND Chronic liver disease is a growing global health problem,leading to hepatic decompensation characterized by an array of clinical and biochemical complic-ations.Several scoring systems have been introduced in assessing the severity of hepatic decompensation with the most frequent ones are Child-Pugh score,model of end-stage liver disease(MELD)score,and MELD-Na score.Anemia is frequently observed in cirrhotic patients and is linked to worsened clinical outcomes.Although studies have explored anemia in liver disease,few have investigated the correlation of hemoglobin level with the severity of hepatic decompensation.AIM To determine the relationship between hemoglobin levels and the severity of decompensated liver disease and comparing the strength of this correlation using the Child-Pugh,MELD,and MELD-Na scores.METHODS This cross-sectional study was conducted at a tertiary care hospital with 652 decompensated liver disease patients enrolled in the study.Data was collected on demographics,clinical history,and laboratory findings,including hemoglobin levels,bilirubin,albumin,prothrombin time(international normalized ratio),sodium,and creatinine.The Child-Pugh,MELD,and MELD-Na scores were calculated.Statistical analysis was performed using Statistical Package for the Social Sciences version 26,and correlations between hemoglobin levels and severity scores were assessed using Spearman's correlation coefficient.RESULTS The study included 405 males(62.1%)and 247 females(37.9%)with an average age of 58.8 years.Significant inverse correlations were found between hemoglobin levels and Child-Pugh,MELD,and MELD-Na scores(P<0.01),with the MELD scoring system being the strongest correlator among all.One-way analysis of variance revealed significant differences in hemoglobin levels across the severity groups of each scoring system(P=0.001).Tukey's post hoc analysis confirmed significant internal differences among each severity group.CONCLUSION Understanding the correlation between hemoglobin and liver disease severity can improve patient management by offering insights into prognosis and guiding treatment decisions. 展开更多
关键词 Hepatic decompensation Hemoglobin level Chronic liver disease Child Turcotte Pugh score Model of end-stage liver disease score Model of end-stage liver disease-Na score
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Improving gastrointestinal scoring systems for predicting short-term mortality in critically ill patients
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作者 Shane Moore Noel E Donlon 《World Journal of Gastroenterology》 2025年第5期137-139,共3页
Shen et al’s retrospective study aims to compare the utility of two separate scoring systems for predicting mortality attributable to gastrointestinal(GI)injury in critically ill patients[the GI Dysfunction Score(GID... Shen et al’s retrospective study aims to compare the utility of two separate scoring systems for predicting mortality attributable to gastrointestinal(GI)injury in critically ill patients[the GI Dysfunction Score(GIDS)and the Acute Gastroin-testinal Injury(AGI)grade].The authors note that this study is the first proposal that suggests an equivalence between the ability of both scores to predict mor-tality at 28 days from intensive care unit(ICU)admission.Shen et al retrospec-tively analysed an ICU cohort of patients utilising two physicians administering both the AGI grade and GIDS score,using electronic healthcare records and ICU flowsheets.Where these physicians disagreed about the scores,the final decision as to the scores was made by an associate chief physician,or chief physician.We note that the primary reason for the development of GIDS was to create a clear score for GI dysfunction,with minimal subjectivity or inter-operator variability.The subjectivity inherent to the older AGI grading system is what ultimately led to the development of GIDS in 2021.By ensuring consensus between physicians administering the AGI,Shen et al have controlled for one of this grading systems biggest issues.We have concerns,however,that this does not represent the real-world challenges associated with applying the AGI compared to the newer GIDS,and wonder if this arbitration process had not been instituted,would the two scoring systems remain equivalent in terms of predicted mortality? 展开更多
关键词 Gastrointestinal injury Critical care Patient mortality prediction Gastrointe-stinal Dysfunction Score Acute Gastrointestinal Injury grade Intensive care unit scoring systems
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GATIS score:An innovative prognostic score for rectal neuroendocrine neoplasms
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作者 Daniel Paramythiotis Dimitrios Tsavdaris Eleni Karlafti 《World Journal of Gastroenterology》 2025年第6期121-125,共5页
In this article,we discussed the article by Zeng et al,published in a recent issue of the World Journal of Gastroenterology.The publication represents a significant advancement in the prognostic evaluation of rectal n... In this article,we discussed the article by Zeng et al,published in a recent issue of the World Journal of Gastroenterology.The publication represents a significant advancement in the prognostic evaluation of rectal neuroendocrine neoplasms.The GATIS score is a single nomogram model that incorporates five key progno-stic factors:Tumor grade;T stage;tumor size;age;and the prognostic nutritional index.This innovation optimizes the prognostic process,delivering more accurate predictions of overall survival and progression-free survival compared to tradi-tional TNM staging and World Health Organization classification systems.The findings of the study were based on a retrospective analysis spanning 12 years and involving 1408 patients from 17 reference centers in China.In this editorial,we specifically examined the strengths and limitations of the study,the clinical implications of the GATIS score,and the questions arising from its conclusions. 展开更多
关键词 Rectal neuroendocrine neoplasm PROGNOSIS SCORE Overall survival Pro-gression-free survival
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Predicting post-hepatectomy liver failure using a nomogram based on portal vein width,inflammatory indices,and the albumin-bilirubin score
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作者 Ke Sun Jiang-Bin Li +3 位作者 Ya-Feng Chen Zhong-Jie Zhai Lang Chen Rui Dong 《World Journal of Gastrointestinal Surgery》 2025年第2期87-96,共10页
BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identif... BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identify potential high-risk PHLF patients as early as possible through preoperative evaluation.AIM To identify risk factors for PHLF and develop a prediction model.METHODS This study included 248 patients with HCC at The Second Affiliated Hospital of Air Force Medical University between January 2014 and December 2023;these patients were divided into a training group(n=164)and a validation group(n=84)via random sampling.The independent variables for the occurrence of PHLF were identified by univariate and multivariate analyses and visualized as nomograms.Ultimately,comparisons were made with traditional models via receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS In this study,portal vein width[odds ratio(OR)=1.603,95%CI:1.288-1.994,P≤0.001],the preoperative neutrophil-to-lymphocyte ratio(NLR)(OR=1.495,95%CI:1.126-1.984,P=0.005),and the albumin-bilirubin(ALBI)score(OR=8.868,95%CI:2.144-36.678,P=0.003)were independent risk factors for PHLF.A nomogram prediction model was developed using these factors.ROC and DCA analyses revealed that the predictive efficacy and clinical value of this model were better than those of traditional models.CONCLUSION A new Nomogram model for predicting PHLF in HCC patients was successfully established based on portal vein width,the NLR,and the ALBI score,which outperforms the traditional model. 展开更多
关键词 NOMOGRAM Hepatocellular carcinoma Post-hepatectomy liver failure Albumin-bilirubin score Portal vein width
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Scoring system supporting suture decision-making for duodenal submucosal tumors
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作者 Zi-Han Geng Yi-Fan Qu +4 位作者 Yan Zhu Pei-Yao Fu Wei-Feng Chen Quan-Lin Li Ping-Hong Zhou 《World Journal of Clinical Oncology》 2025年第3期20-29,共10页
BACKGROUND In recent years,endoscopic resection(ER)has been employed for the excision of submucosal tumors(SMTs).Nonetheless,ER in the duodenum is linked to ele-vated risks of both immediate and delayed hemorrhagic co... BACKGROUND In recent years,endoscopic resection(ER)has been employed for the excision of submucosal tumors(SMTs).Nonetheless,ER in the duodenum is linked to ele-vated risks of both immediate and delayed hemorrhagic complications and perforations.Satisfactory suturing is crucial for reducing the occurrence of complications.AIM To establish a clinical score model for supporting suture decision-making of duodenal SMTs.METHODS This study included 137 individuals diagnosed with duodenal SMTs who under-went ER.Participants were evenly divided into two groups:A training cohort(TC)comprising 95 cases and an internal validation cohort(VC)with 42 cases.Subsequently,a scoring system was formulated utilizing multivariate logistic regression analysis within the TC,which was then subjected to evaluation in the VC.RESULTS The clinical scoring system incorporated two key factors:Extraluminal growth,which was assigned 2 points,and endoscopic full-thickness resection,which was given 3 points.This model demonstrated strong predictive accuracy,as evidenced by the area under the receiver operating characteristic curve of 0.900(95%confidence interval:0.823-0.976).Additionally,the model’s goodness-of-fit was validated by the Hosmer-Lemeshow test(P=0.404).The probability of purse-string suturing in low(score 0-2)and high(score>3)categories were 3.0%and 64.3%in the TC,and 6.1%and 88.9%in the VC,respectively.CONCLUSION This scoring system may function as a beneficial instrumentality for medical practitioners,facilitating the decision-making process concerning suture techniques in the context of duodenal SMTs. 展开更多
关键词 Endoscopic resection Duodenal submucosal tumors Clinical score model Suturing technique Submucosal tumors
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Efficacy-cost analysis of endoscopic mucosal resection and cold snare polypectomy:A propensity score matching analysis
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作者 Shi-Yi Zhang Ying-Chun Wang +2 位作者 Lei-Lei Liu Zhi-Heng Wang Xue-Mei Guan 《World Journal of Gastrointestinal Surgery》 2025年第2期77-86,共10页
BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences b... BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences between CSP and traditional endoscopic mucosal resection(EMR)for the treatment of intestinal polyps.AIM To compare the efficacy-cost of EMR and CSP in the treatment of intestinal polyps.METHODS A total of 100 patients with intestinal polyps were included in the retrospective data of our hospital from April 2022 to May 2023.According to the treatment methods,they were divided into EMR(n=46)group and CSP(n=54)group.The baseline data of the two groups were balanced by 1:1 propensity score matching(PSM),and the cost-effectiveness analysis was performed on the two groups after matching.The recurrence rate of the two groups of patients was followed up for 1 year,and they were divided into recurrence group and non-recurrence group according to whether they recurred.Multivariate logistic regression analysis was used to screen out the influencing factors affecting the recurrence of intestinal polyps after endoscopic resection.RESULTS Significant disparities were observed in the number of polyps and smoking background between the two groups before PSM(P<0.05).Following PSM,the number of polyps and smoking history were well balanced between the EMR and CSP groups.The direct cost incurred by the CSP group was markedly higher than that incurred by the EMR group.Concurrently,the cost-effectiveness ratio in the CSP group was substantially reduced when juxtaposed with that in the EMR group(P<0.05).Upon completion of the 1-year follow-up,the rate of recurrence after endoscopic intestinal polypectomy was 38.00%.Multivariate methods revealed that age≥60 years,male sex,number of polyps≥3,and pathological type of adenoma were risk factors for recurrence after endoscopic intestinal polypectomy(all P<0.05).CONCLUSION CSP was more cost-effective for the treatment of intestinal polyps.An age≥60 years,male sex,having a number of polyps≥3,and pathological type of adenoma are independent influencing factors for recurrence. 展开更多
关键词 Propensity score matching method Endoscopic mucosal resection Cold snare polypectomy Intestinal polyps Curative effect Cost analysis
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Laparoscopic hepatectomy using indocyanine green attenuates postoperative inflammatory response for hepatocellular carcinoma:A propensity score matching analysis
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作者 Wei-Xun Wu Ming-Bin Huang +3 位作者 Mei-Xia Wang Li-Hua Chen Bo Hu Zhen-Bin Ding 《World Journal of Gastrointestinal Surgery》 2025年第1期193-202,共10页
BACKGROUND Improving the intraoperative and postoperative performance of laparoscopic hepatectomy was quite a challenge for liver surgeons.AIM To determine the benefits of indocyanine green(ICG)fluorescence imaging in... BACKGROUND Improving the intraoperative and postoperative performance of laparoscopic hepatectomy was quite a challenge for liver surgeons.AIM To determine the benefits of indocyanine green(ICG)fluorescence imaging in patients with hepatocellular carcinoma(HCC)who underwent laparoscopic hepatectomy during and after surgery.METHODS We retrospectively collected the clinicopathological data of 107 patients who successfully underwent laparoscopic hepatectomy at Zhongshan Hospital(Xiamen),Fudan University from June 2022 to June 2023.Whether using the ICG fluorescence imaging technique,we divided them into the ICG and non-ICG groups.To eliminate statistical bias,a 1:1 propensity score matching analysis was conducted.The comparison of perioperative outcomes,including inflammationrelated markers and progression-free survival,was analyzed statistically.RESULTS Intraoperatively,the ICG group exhibited lower blood loss,a shorter surgical time,lower hepatic inflow occlusion(HIO)frequency,and a shorter total HIO time.Postoperatively,the participation of ICG resulted in a shorter duration of hospitalization(6.5 vs 7.6 days,P=0.03)and postoperative inflammatory response attenuation(lower neutrophil-lymphocyte ratio on the first day after surgery and platelet-lymphocyte ratio on the third day,P<0.05).Although the differences were not significant,the levels of all inflammation-related markers were lower in the ICG group.The rates of postoperative complications and the survival analyses,including progression-free and overall survivals showed no significant difference between the groups.CONCLUSION The involvement of ICG fluorescence imaging may lead to improved perioperative outcomes,especially postoperative inflammatory response attenuation,and ultimately improve HCC patients’recovery after surgery. 展开更多
关键词 Hepatocellular carcinoma Laparoscopic hepatectomy Indocyanine green fluorescence Postoperative inflammatory response attenuation Propensity score matching analysis
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Radiomics-based predictive risk score: A scoring system for preoperatively predicting risk of lymph node metastasis in patients with resectable non-small cell lung cancer 被引量:10
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作者 Lan He Yanqi Huang +3 位作者 Lixu Yan Junhui Zheng Changhong Liang Zaiyi Liu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第4期641-652,共12页
Objective: To develop and validate a radiomics-based predictive risk score(RPRS) for preoperative prediction of lymph node(LN) metastasis in patients with resectable non-small cell lung cancer(NSCLC).Methods: We retro... Objective: To develop and validate a radiomics-based predictive risk score(RPRS) for preoperative prediction of lymph node(LN) metastasis in patients with resectable non-small cell lung cancer(NSCLC).Methods: We retrospectively analyzed 717 who underwent surgical resection for primary NSCLC with systematic mediastinal lymphadenectomy from October 2007 to July 2016. By using the method of radiomics analysis, 591 computed tomography(CT)-based radiomics features were extracted, and the radiomics-based classifier was constructed. Then, using multivariable logistic regression analysis, a weighted score RPRS was derived to identify LN metastasis. Apparent prediction performance of RPRS was assessed with its calibration,discrimination, and clinical usefulness.Results: The radiomics-based classifier was constructed, which consisted of 13 selected radiomics features.Multivariate models demonstrated that radiomics-based classifier, age group, tumor diameter, tumor location, and CT-based LN status were independent predictors. When we assigned the corresponding score to each variable,patients with RPRSs of 0-3, 4-5, 6, 7-8, and 9 had distinctly very low(0%-20%), low(21%-40%), intermediate(41%-60%), high(61%-80%), and very high(81%-100%) risks of LN involvement, respectively. The developed RPRS showed good discrimination and satisfactory calibration (C-index: 0.785, 95% confidence interval(95% CI):0.780-0.790)Additionally, RPRS outperformed the clinicopathologic-based characteristics model with net reclassification index(NRI) of 0.711(95% CI: 0.555-0.867).Conclusions: The novel clinical scoring system developed as RPRS can serve as an easy-to-use tool to facilitate the preoperatively individualized prediction of LN metastasis in patients with resectable NSCLC. This stratification of patients according to their LN status may provide a basis for individualized treatment. 展开更多
关键词 LYMPH node radiomics RISK SCORE CT NON-SMALL cell LUNG cancer
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Validation of a new scoring system: Rapid assessment faecal incontinence score 被引量:5
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作者 Fernando de la Portilla Arantxa Calero-Lillo +4 位作者 Rosa M Jiménez-Rodríguez Maria L Reyes Manuela Segovia-González María Victoria Maestre Ana M García-Cabrera 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2015年第9期203-207,共5页
AIM: To implement a quick and simple test- rapid assessment faecal incontinence score(RAFIS) and show its reliability and validity.METHODS: From March 2008 through March 2010, we evaluated a total of 261 consecutive p... AIM: To implement a quick and simple test- rapid assessment faecal incontinence score(RAFIS) and show its reliability and validity.METHODS: From March 2008 through March 2010, we evaluated a total of 261 consecutive patients, including 53 patients with faecal incontinence. Demographic and comorbidity information was collected. In a single visit, patients were administered the RAFIS. The results obtained with the new score were compared with those of both Wexner score and faecal incontinence quality of life scale(FIQL) questionnaire. The patient withoutinfluence of the surgeon completed the test. The role of surgeon was explaining the meaning of each section and how he had to fill. Reliability of the RAFIS score was measured using intra-observer agreement and Cronbach's alpha(internal consistency) coefficient. Multivariate analysis of the main components within the different scores was performed in order to determine whether all the scores measured the same factor and to conclude whether the information could be encompassed in a single factor. A sample size of 50 patients with faecal incontinence was estimated to be enough to detect a correlation of 0.55 or better at 5% level of significance with 80% power.RESULTS: We analysed the results obtained by 53 consecutive patients with faecal incontinence(median age 61.55 ± 12.49 years) in the three scoring systems. A total of 208 healthy volunteers(median age 58.41 ± 18.41 years) without faecal incontinence were included in the study as negative controls. Pearson's correlation coefficient between "state" and "leaks" was excellent(r = 0.92, P < 0.005). Internal consistency in the comparison of "state" and "leaks" yielded also excellent correlation(Cronbach's α = 0.93). Results in each score were compared using regression analysis and a correlation value of r = 0.98 was obtained with Wexner score. As regards FIQL questionnaire, the values of "r " for the different subscales of the questionnaire were: "lifestyle" r =-0.87, "coping/behaviour" r =-0.91, "depression" r =-0.36 and "embarrassment" r =-0.90,(P < 0.01). A multivariate analysis showed that all the scoring systems measured the same factor. A single factor may explain 80.84% of the variability of FI, so all the scoring systems measure the same factor. Patient's continence improves when RAFIS and Jorge-Wexner scores show low values and when the values obtained in the FIQL questionnaire are high.CONCLUSION: RAFIS is a valid and reliable tool to assess Faecal Incontinence. 展开更多
关键词 FAECAL INCONTINENCE MEASURE SCORE TEST FAECAL inco
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A semi-quantitative coal burst risk classification system 被引量:5
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作者 Onur Vardar Chengguo Zhang +1 位作者 Ismet Canbulat Bruce Hebblewhite 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第5期721-727,共7页
Safety is the highest priority in the mining industry as underground mining in particular poses high safety risks to its workers. In underground coal mines, coal bursts are one of the most catastrophic hazards, which ... Safety is the highest priority in the mining industry as underground mining in particular poses high safety risks to its workers. In underground coal mines, coal bursts are one of the most catastrophic hazards, which involves sudden and violent dynamic coal mass failure with rapid ejection of the broken material into the mine workings. Despite decades of research, the contributing mechanisms of coal bursts are still not completely understood. Hence, it remains challenging to forecast coal bursts and quantify their likelihood of occurrence. However, a range of geological and geotechnical factors are associated with coal bursts and can increase the coal burst proneness. This paper introduces a semi-quantitative coal burst risk classification system, namely, BurstRisk. Based on back-analysis of case histories from Australia, China and the United States, BurstRisk classifies the coal burst risk into three categories:low, medium and high risk. In addition, it allows mining engineers to modify the weighting of the selected factors based on specific conditions. The risk classification charts introduced are for both longwall retreat and development sections of long-wall mining operations. This paper also provides a set of risk management strategies and control measures for effective coal burst mitigation. 展开更多
关键词 UNDERGROUND COAL MINING COAL BURST ROCKBURST Risk management Safety semi-quantitative
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A Semi-Quantitative Analysis of Essential Micronutrient in Folium Lycii Using Laser-Induced Breakdown Spectroscopy Technique 被引量:3
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作者 孙对兄 苏茂根 +2 位作者 董晨钟 张大成 马新文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第4期478-481,共4页
Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Bas... Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Based on homogeneous plasma assumption, nine of essential micronutrients in folium lycii are identified. Using Saha equation and Boltzmann plot method electron density and plasma temperature are obtained, and their relative concentration (Ca, Mg, A1, Si, Ti, Na, K, Li, and Sr) are obtained employing a semi-quantitative method. 展开更多
关键词 PLASMA LIBS folium lycii semi-quantitative analysis
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基于Z-Score动态压缩的高效联邦学习算法
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作者 刘乔寿 皮胜文 原炜锡 《计算机应用研究》 CSCD 北大核心 2024年第7期2093-2097,共5页
联邦学习作为一种具有隐私保护的新兴分布式计算范式,在一定程度上保护了用户隐私和数据安全。然而,由于联邦学习系统中客户端与服务器需要频繁地交换模型参数,造成了较大的通信开销。在带宽有限的无线通信场景中,这成为了限制联邦学习... 联邦学习作为一种具有隐私保护的新兴分布式计算范式,在一定程度上保护了用户隐私和数据安全。然而,由于联邦学习系统中客户端与服务器需要频繁地交换模型参数,造成了较大的通信开销。在带宽有限的无线通信场景中,这成为了限制联邦学习发展的主要瓶颈。针对这一问题,提出了一种基于Z-Score的动态稀疏压缩算法。通过引入Z-Score,对局部模型更新进行离群点检测,将重要的更新值视为离群点,从而将其挑选出来。在不需要复杂的排序算法以及原始模型更新的先验知识的情况下,实现模型更新的稀疏化。同时随着通信轮次的增加,根据全局模型的损失值动态地调整稀疏率,从而在保证模型精度的前提下最大程度地减少总通信量。通过实验证明,在I.I.D.数据场景下,该算法与联邦平均(FedAvg)算法相比可以降低95%的通信量,精度损失仅仅为1.6%,与FTTQ算法相比可以降低40%~50%的通信量,精度损失仅为1.29%,证明了该方法在保证模型性能的同时显著降低了通信成本。 展开更多
关键词 联邦学习 Z-SCORE 稀疏化 动态稀疏率
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A Semi-quantitative Serological Method to Assess the Potency of Inactivated Rabies Vaccine for Veterinary Use 被引量:1
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作者 Ye Liu Shoufeng Zhang +1 位作者 Fei Zhang Rongliang Hu 《Virologica Sinica》 CAS CSCD 2012年第4期259-264,共6页
Potency is one of the most important indexes of inactivated vaccines.A number of methods have been established to assay the potency,of which the NIH test and single-dose mouse protection test are the "prescribed ... Potency is one of the most important indexes of inactivated vaccines.A number of methods have been established to assay the potency,of which the NIH test and single-dose mouse protection test are the "prescribed methods".Here,we report a method to semi-quantitatively assay the potency of an inactivated rabies vaccine,which uses fewer animals and takes less time to complete.Depending on the quality requirements of a vaccine(e.g.minimum potency),a rabies reference vaccine is,for example,diluted to the minimum potency,and 50 μL of the dilution is taken to inoculate 10 mice.The same amount of the test rabies vaccine is inoculated into another 10 mice.After two weeks,all mice are bled and serum samples are assayed for viral neutralizing antibody by the fluorescent antibody virus neutralization(FAVN) test.By comparing the median and interquartile range of antibody titers of the reference vaccine with those of the test vaccine,the test vaccine potency can be semi-quantitatively judged as to whether it is in accord with the required quality.The reliability of this method was also confirmed in dogs.The procedure can be recommended for batch potency testing during inactivated rabies vaccine production. 展开更多
关键词 RABIES Inactivated vaccine Potency assay semi-quantitative method
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Can semi-quantitative evaluation of uncertain (type II) time-intensity curves improve diagnosis in breast DCE-MRI? 被引量:1
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作者 Roberta Fusco Salvatore Filice +9 位作者 Vincenza Granata Ylenia Mandato Annamaria Porto Massimiliano D’Aiuto Massimo Rinaldo Maurizio Di Bonito Mario Sansone Carlo Sansone Antonio Rotondo Antonella Petrillo Petrillo 《Journal of Biomedical Science and Engineering》 2013年第3期418-425,共8页
Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative asse... Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative assessment of uncertain TICs could improve overall diagnostic performance. Methods: In this study 49 lesions from 44 patients were retrospectively analysed. Per each lesion one region-of-interest (ROI)- averaged TIC was qualitatively evaluated by two radiologists in consensus: all the ROIs resulted in type II (uncertain) TIC. The same TICs were semi-quantitatively re-classified on the basis of the difference between the signal intensities of the last-time-point and of the peak: this difference was classified according to two different cut-off ranges (±5% and ±3%). All patients were cytological or histological biopsy proven. Fisher test and McNemar test were performed to evaluate if results were statistically significant (p < 0.05). Results: Using ±5% cut-off 16 TICs were reclassified as type III and 12 as type I while 21 were reclassified again as type II. Using ±3% 22 TICs were reclassified as type III and 16 as type I while 11 were reclassified again as type II. The semi-quantitative classification was compared to the histological-cytological results: the sensitivity, specificity, positive and negative predictive values obtained with ±3% were 77%, 91%, 91% and 78% respectively while using ±5% were 58%, 96%, 94% and 68% respectively. Using the ±5% cut-off 26/28 (93%) TICs were correctly reclassified while using the ±3% cut-off 34/38 (90%) TICs were correctly reclassified (p < 0.05). Conclusions: Semi-quantitative methods in kinetic curve assessment on DCE-MRI could improve classification of qualitatively uncertain TICs, leading to a more accurate classification of suspicious breast lesions. 展开更多
关键词 BREAST Cancer Dynamic CONTRAST Enhanced-MRI Time Intensity CURVE TRACER Kinetics semi-quantitative Analysis
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基于F-score和二进制灰狼优化的肿瘤基因选择方法
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作者 穆晓霞 郑李婧 《南京师大学报(自然科学版)》 CAS 北大核心 2024年第1期111-120,共10页
针对肿瘤基因数据维度高、噪声多、冗余性高的现状,结合Spearman相关系数改进F-score算法,在此基础上优化二进制灰狼算法,提出了一种基于改进F-score和二进制灰狼算法的肿瘤基因选择算法.首先,考虑特征之间的相关性,计算每个特征的F-sc... 针对肿瘤基因数据维度高、噪声多、冗余性高的现状,结合Spearman相关系数改进F-score算法,在此基础上优化二进制灰狼算法,提出了一种基于改进F-score和二进制灰狼算法的肿瘤基因选择算法.首先,考虑特征之间的相关性,计算每个特征的F-score值和特征之间的Spearman相关系数的绝对值;然后,计算权重系数得出各个特征的权重值,依据重要性进行排序,选出初选特征子集;最后,通过收敛因子的衰减曲线和初始化方法优化二进制灰狼算法,调整全局搜索和局部搜索所占比例,增强全局搜索能力并提高局部搜索速度,有效节省时间开销,提升特征选择的分类性能和效率,得到最优特征子集.在9个肿瘤基因数据集上测试所提算法,在分类准确率和筛选特征数目两个指标上进行仿真实验,并与4种其他算法进行对比,实验结果证明所提算法表现良好,可有效降低基因数据维度,并具有较好的分类精度. 展开更多
关键词 肿瘤基因 Fisher-score Spearman 相关系数 二进制灰狼优化算法 特征选择
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引入ESG框架的Z-Score业绩评价模式研究
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作者 柯剑 曾锦晴 《管理会计研究》 2024年第6期79-88,共10页
本文结合当前企业可持续高质量发展的目标导向,构建了引入ESG框架的Z-Score业绩评价模式,以弥补EVA评价中过于关注经济利润以及BSC评价中过于关注企业内部治理的视角局限性。通过主成分分析法测度的关键综合业绩指标,在案例分析中证明... 本文结合当前企业可持续高质量发展的目标导向,构建了引入ESG框架的Z-Score业绩评价模式,以弥补EVA评价中过于关注经济利润以及BSC评价中过于关注企业内部治理的视角局限性。通过主成分分析法测度的关键综合业绩指标,在案例分析中证明了引入ESG框架后的业绩评价模式在实际应用中具有必要性和合理性。在传统业绩指标评价模式的基础上引入ESG框架来进一步优化企业业绩评价体系,有助于企业培育或强化适应高质量发展的业绩观。 展开更多
关键词 ESG 业绩评价 BSC EVA Z-SCORE
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Research on Fast Semi-Quantitative Risk Assessment Method for High Temperature and High Pressure Gas Wells
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作者 Mifeng Zhao Hailong Geng +2 位作者 Jingcheng Zhang Junfeng Xie Kelin Wang 《World Journal of Engineering and Technology》 2021年第1期100-108,共9页
Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temp... Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temperature and pressure is studied. Based on the rapid risk assessment method of annulus well with pressure in Chevron Company and the existing risk assessment methods, the well barrier and annulus pressure of high temperature and high pressure gas wells are fully considered. A rapid semi-quantitative risk assessment method for high temperature and high pressure gas wells is established, which takes the annulus pressure value, well service life, annulus pressure recovery after pressure relief, reservoir conditions (formation pressure, production) and well CO<sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2 </span></sub><span style="font-family:Verdana;">and H</span><sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">S content as the key risk indexes. The method is applied in a gas field, and the risk value and risk grade of a practical well are semi-quantitatively evaluated. The overall risk situation of the well is obtained. The research results provide important technical guidance for the safe production of gas well.</span> 展开更多
关键词 HPHT semi-quantitative Risk Assessment Quantitative scoring
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Diagnostic tools for fecal incontinence: Scoring systems are the crucial first step 被引量:2
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作者 Peter Liptak Martin Duricek Peter Banovcin 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期516-522,共7页
The main aim of this editorial is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593-4603.This original research presents a new scoring system for fecal inco... The main aim of this editorial is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593-4603.This original research presents a new scoring system for fecal incontinence.Fecal incontinence is a chronic disease with a severe impact on the quality of life of the patients.Substantial social stigmatization often leads to significant underreporting of the condition even during visits to a specialist and could lead to further misman-agement or non-existent management of the disease.An important fact is that patients are often unable to describe their condition when not asked precisely defined questions.This problem is partially resolved by scoring questionnaires.Several scoring systems are commonly used;however,each of them has their shortcomings.For example,the absence of different kinds of leakage besides flatus and stool could further lead to underscoring the incontinence severity.Therefore,there has long been a call for a more precise scoring system.The correct identification of the presence and severity of fecal incontinence is paramount for further diagnostic approach and for choosing the appropriate therapy option.This editorial describes fecal incontinence,its effect on quality of life in general and further evaluates the diagnostic approach with a particular focus on symptom scoring systems and their implications for clinical practice. 展开更多
关键词 INCONTINENCE FECAL scoring system Questionary Quality of life
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