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A Novel Insertion Solution for the Travelling Salesman Problem
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作者 Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka +5 位作者 Sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson Adekunle Pragasen Mudali Matthew Olusegun Adigun 《Computers, Materials & Continua》 SCIE EI 2024年第4期1581-1597,共17页
The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) a... The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies. 展开更多
关键词 Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem
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Enhancing hydrogen evolution and oxidation kinetics through oxygen insertion into nickel lattice
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作者 Wanli Liang Xiyu Gong +9 位作者 Jinchang Xu Zixuan Dan Fanyan Xie Hulei Yu Hao-Fan Wang Yanshuo Jin Hongjuan Wang Yonghai Cao Hui Meng Hao Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期529-539,I0012,共12页
Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution rea... Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO_(2)).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorption strength of^(*)H and^(*)OH on Ni is optimized,thus resulting in superior electrocatalytic performance of0-Ni/WO_(2)in alkaline HER/HOR.The Tafel slope of O-Ni/WO_(2)@NF for HER is 56 mV dec^(-1),and the kinetic current density of O-Ni/WO_(2)for HOR reaches 4.85 mA cm^(-2),which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts. 展开更多
关键词 Hydrogen evolution Hydrogen oxidation NICKEL Oxygen insertion Adsorption free energy
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An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
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作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
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Velamentous Cord Insertion: Interest of Antenatal Diagnosis and Review of the Literature
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作者 Karam Harou Aboubacar Sidiki Sidibe +1 位作者 Hicham Abdelkhalki Abderaouf Soummani 《Open Journal of Obstetrics and Gynecology》 2024年第2期234-239,共6页
Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be d... Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be diagnosed during the morphological ultrasound of the 2nd trimester, actively looking for the association with a vasa previa, due to the risk of fetal haemorrhagic threat. We report an antenatal diagnosis of velamentous cord insertion and its management with literature review. 展开更多
关键词 Velamentous Cord insertion Vasa Previa Antenatal Diagnosis Ultrasound Doppler Benckiser’s Hemorrhage
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Treatment of benign rectal stricture caused by repeated anal insertion by endoscopy and balloon dilation:A case report
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作者 Shih-Hung Liu Jung-Cheng Kang +3 位作者 Je-Ming Hu Chao-Yang Chen Kuan-Hsun Lin Ta-Wei Pu 《World Journal of Gastrointestinal Endoscopy》 2024年第2期91-97,共7页
BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have dive... BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have diverse etiologies,including various inflammatory conditions.Benign strictures are usually managed by surgery and endoscopy.We present an unusual etiology of benign rectal stricture caused by the repeated insertion of foreign objects into the rectum for sexual purposes,resulting in rectal injury and subsequent chronic inflammation.CASE SUMMARY A 53-year-old man presented to the outpatient clinic of the Colorectal Surgery Department with symptoms of chronic constipation and bloody stools.The patient previously experienced rectal injury due to foreign object insertion for sexual purposes.Colonoscopy revealed benign circumferential narrowing of the rectum.He underwent treatment by endoscopic argon plasma coagulation and balloon dilation and follow-up as an outpatient for 4 months.A colonoscopy at the end of the follow-up period revealed no evidence of rectal stricture relapse.CONCLUSION A history of rectal injury,followed by chronic inflammation,should be considered in patients with benign rectal strictures.Management with endoscopic argon plasma coagulation and balloon dilation can prevent the need for surgical resection of benign rectal strictures. 展开更多
关键词 Chronic rectal inflammation COLONOSCOPY Benign rectal stricture Foreign body insertion Rectal injury Case report
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Atomic-scale insights of indium segregation and its suppression by GaAs insertion layer in InGaAs/AlGaAs multiple quantum wells 被引量:1
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作者 马淑芳 李磊 +8 位作者 孔庆波 徐阳 刘青明 张帅 张西数 韩斌 仇伯仓 许并社 郝晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期544-548,共5页
The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected sc... The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs. 展开更多
关键词 InGaAs/AlGaAs quantum well GaAs insertion layer In segregation scanning transmission electron microscopy
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Complications Related to the Insertion Technique of Jadelle® Contraceptive Implants
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作者 Astou Coly Niassy Moussa Diallo +5 位作者 Tatiana Sandjon Ibrahim Rahadat Marie-Édouard Faye Ndeye Fatou Coulibaly Alassane Diouf Jean-Charles Moreau 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期166-174,共9页
Introduction: Contraceptive implants are one of the most effective methods of birth spacing. Jadelle<sup>&reg;</sup> implants consist of two strands that are easy to insert and remove. Although their e... Introduction: Contraceptive implants are one of the most effective methods of birth spacing. Jadelle<sup>&reg;</sup> implants consist of two strands that are easy to insert and remove. Although their effectiveness is no longer in question, their use (insertion) requires a surgical procedure with the corollary possibility of complications. These are mainly insertions that are too deep (in the arm muscle), vascular and nerve damage. Material and Methods: Our study focused on complications related to implant insertion. It was a descriptive and retrospective study over thirty-four months, from October 2016 to July 2019, and concerned all patients seen in consultation and who presented a complication related to the insertion of contraceptive implants in the Department of Gynecology and Obstetrics of the National Hospital of Pikine. Results: We collected nine complications managed at the Gynecology and Obstetrics Department of the Centre Hospitalier National de Pikine from 2016 to 2019. These were insertions that were too deep with sometimes nerve damage, infection or incident during anesthesia. The operative procedures were based on the type of complication. Conclusion: Although Jadelle<sup>&reg;</sup> has the advantage of having only 2 rods compared to its predecessor Norplant<sup>&reg;</sup>, its use is also conditioned by insertion and removal procedures which may experience complications. 展开更多
关键词 CONTRACEPTION IMPLANTS Incidents insertion REMOVAL
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Complicated expansion trajectories of insertion sequences and potential association with horizontal transfer of Wolbachia DNA
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作者 Yun-Heng Miao Da-Wei Huang Jin-Hua Xiao 《Zoological Research》 SCIE CAS CSCD 2023年第2期273-275,共3页
DEAR EDITOR,Insertion sequences(ISs) are the simplest structural transposable elements(TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to th... DEAR EDITOR,Insertion sequences(ISs) are the simplest structural transposable elements(TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to their gradually streamlined genomic construction, TEs rarely exist in the genomes of obligate endosymbionts. However, TE content, especially ISs. 展开更多
关键词 SEQUENCES insertion WOLBACHIA
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Promoter insertion leads to polyembryony in mango-a case of convergent evolution with citrus
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作者 Chandra Bhan Yadav Ada Rozen +9 位作者 Ravit Eshed Mazal Ish-Shalom Adi Faigenboim Natalie Dillon Ian Bally Matthew Webb David Kuhn Ron Ophir Yuval Cohen Amir Sherman 《Horticulture Research》 SCIE CSCD 2023年第12期165-174,共10页
Sexual reproduction in plants is the main pathway for creating new genetic combinations in modern agriculture.In heterozygous plants,after the identification of a plant with desired traits,vegetative propagation(cloni... Sexual reproduction in plants is the main pathway for creating new genetic combinations in modern agriculture.In heterozygous plants,after the identification of a plant with desired traits,vegetative propagation(cloning)is the primary path to create genetically uniform plants.Another natural plant mechanism that creates genetically uniform plants(clones)is apomixis.In fruit crops like citrus and mango,sporophytic apomixis results in polyembryony,where seeds contain multiple embryos,one of which is sexually originated and the others are vegetative clones of the parent mother tree.Utilizing the mango genome and genetic analysis of a diverse germplasm collection,we identified MiRWP as the gene that causes polyembryony in mango.There is a strong correlation between a specific insertion in the gene’s promoter region and altered expression in flowers and developing fruitlets,inducing multiple embryos.The MiRWP gene is an ortholog of CitRWP that causes polyembryony in citrus.Based on the data,we speculate that promoter insertion events,which occurred independently in citrus and mango,induced nucellar embryogenesis.The results suggest convergent evolution of polyembryony in the two species.Further work is required to demonstrate the utility of these genes(mango and citrus)in other biological systems as a tool for the clonal production of other crops. 展开更多
关键词 CITRUS CROPS insertion
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Novel GaN-based double-channel p-heterostructure field-effect transistors with a p-GaN insertion layer
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作者 牛雪锐 侯斌 +7 位作者 张濛 杨凌 武玫 张新创 贾富春 王冲 马晓华 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期678-683,共6页
GaN-based p-channel heterostructure field-effect transistors(p-HFETs)face significant constraints on on-state currents compared with n-channel high electron mobility transistors.In this work,we propose a novel double ... GaN-based p-channel heterostructure field-effect transistors(p-HFETs)face significant constraints on on-state currents compared with n-channel high electron mobility transistors.In this work,we propose a novel double heterostructure which introduces an additional p-GaN insertion layer into traditional p-HFETs.The impact of the device structure on the hole densities and valence band energies of both the upper and lower channels is analyzed by using Silvaco TACD simulations,including the thickness of the upper AlGaN layer and the doping impurities and concentration in the GaN buffer layer,as well as the thickness and Mg-doping concentration in the p-GaN insertion layer.With the help of the p-GaN insertion layer,the C-doping concentration in the GaN buffer layer can be reduced,while the density of the two-dimensional hole gas in the lower channel is enhanced at the same time.This work suggests that a double heterostructure with a p-GaN insertion layer is a better approach to improve p-HFETs compared with those devices with C-doped buffer layer alone. 展开更多
关键词 GaN double-channel heterostructure field-effect transistors p-GaN insertion layer C-doped buffer layer
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Researchers Develop New Tools for Precise Large DNA Insertions
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作者 GAO Caixia 《Bulletin of the Chinese Academy of Sciences》 2023年第2期115-116,共2页
GAO Caixia’s group from the Institute of Genetics and Developmental Biology(IGDB)of the Chinese Academy of Sciences(CAS)has developed a new genome editing technology that achieves efficient and precise targeted inser... GAO Caixia’s group from the Institute of Genetics and Developmental Biology(IGDB)of the Chinese Academy of Sciences(CAS)has developed a new genome editing technology that achieves efficient and precise targeted insertion of large DNA segments in plants.The new technology,called prime editing-mediated recombination of opportune targets(PrimeRoot),combines an optimized dual-ePPE editor protein previously published by the group with a highly efficient tyrosine site-specific recombinase,Cre.It can achieve one-step,precise targeted insertion of large DNA segments in rice and maize with an efficiency up to 6%and has been used to successfully insert DNA segments up to 11.1 kb. 展开更多
关键词 PRECISE insertion EDITOR
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Esophageal inserted subclavian catheter:a rare complication
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作者 DilberÜçöz Kocaşaban SertaçGüler 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期243-245,共3页
Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemake... Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4] 展开更多
关键词 UNSTABLE insertion initially
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Tubular Heat Enhancement Using Twisted Tape Inserts with Large Holes
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作者 Ali Jaber Abdulhamed Aws Al-Akam +1 位作者 Wisam J.Khudhayer Ali Sabri Allw 《Energy Engineering》 EI 2024年第2期273-290,共18页
Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fi... Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fillers inside the tubes to enhance heat transfer.This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting factor.In the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular cross-section.The turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was constructed.The findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as well.Additionally,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably higher.Additionally,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube values.The maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated. 展开更多
关键词 TUBULAR heat exchanger tape inserts twisted tape
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Establishment and validation of a predictive model for peripherally inserted central catheter-related thrombosis in patients with liver cancer
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作者 Xiao-Fei Chen Hao-Jun Wu +3 位作者 Tang Li Jia-Bin Liu Wen-Jie Zhou Qiang Guo 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2221-2231,共11页
BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other medications.However,PICC-related thrombo... BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other medications.However,PICC-related thrombosis is a serious complication that can lead to morbidity and mortality in this patient population.Several risk factors have been identified for the development of PICC-related thrombosis,including cancer type,stage,comorbidities,and catheter characteristics.Understanding these risk factors and developing a predictive model can help healthcare providers identify high-risk patients and implement preventive measures to reduce the incidence of thrombosis.AIM To analyze the influencing factors of PICC-related thrombosis in hospitalized patients with liver cancer,construct a predictive model,and validate it.METHODS Clinical data of hospitalized patients with liver cancer admitted from January 2020 to December 2023 were collected.Thirty-five cases of PICC-related thrombosis in hospitalized patients with liver cancer were collected,and 220 patients who underwent PICC placement during the same period but did not develop PICC-related thrombosis were randomly selected as controls.A total of 255 samples were collected and used as the training set,and 77 cases were collected as the validation set in a 7:3 ratio.General patient information,case data,catheterization data,coagulation indicators,and Autar Thrombosis Risk Assessment Scale scores were analyzed.Univariate and multivariate unconditional logistic regression analyses were performed on relevant factors,and the value of combined indicators in predicting PICC-related thrombosis in hospitalized patients with liver cancer was evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Univariate analysis showed statistically significant differences(P<0.05)in age,sex,Karnofsky performance status score(KPS),bedridden time,activities of daily living impairment,parenteral nutrition,catheter duration,distant metastasis,and bone marrow suppression between the thrombosis group and the non-thrombosis group.Other aspects had no statistically significant differences(P>0.05).Multivariate regression analysis showed that age≥60 years,KPS score≤50 points,parenteral nutrition,stage III to IV,distant metastasis,bone marrow suppression,and activities of daily living impairment were independent risk factors for PICC-related thrombosis in hospitalized patients with liver cancer(P<0.05).Catheter duration of 1-6 months and catheter duration>6 months were protective factors for PICC-related thrombosis(P<0.05).The predictive model for PICC-related thrombosis was obtained as follows:P predictive probability=[exp(Logit P)]/[1+exp(Logit P)],where Logit P=age×1.907+KPS score×2.045+parenteral nutrition×9.467+catheter duration×0.506+tumor-node-metastasis(TNM)staging×2.844+distant metastasis×2.065+bone marrow suppression×2.082+activities of daily living impairment×13.926.ROC curve analysis showed an area under the curve(AUC)of 0.827(95%CI:0.724-0.929,P<0.001),with a corresponding optimal cut-off value of 0.612,sensitivity of 0.755,and specificity of 0.857.Calibration curve analysis showed good consistency between the predicted occurrence of PICC-related thrombosis and actual occurrence(P>0.05).ROC analysis showed AUCs of 0.888 and 0.729 for the training and validation sets,respectively.CONCLUSION Age,KPS score,parenteral nutrition,TNM staging,distant metastasis,bone marrow suppression,and activities of daily living impairment are independent risk factors for PICC-related thrombosis in hospitalized patients with liver cancer,while catheter duration is a protective factor for the disease.The predictive model has an AUC of 0.827,indicating high predictive accuracy and clinical value. 展开更多
关键词 Liver cancer Peripherally inserted central catheters THROMBOSIS Model Verify
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Lower extremity peripherally inserted central catheter placement ectopic to the ascending lumbar vein:A case report
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作者 Xiao-Ju Zhu Ling Zhao +2 位作者 Na Peng Jia-Min Luo Shui-Xia Liu 《World Journal of Clinical Cases》 SCIE 2024年第8期1430-1436,共7页
BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients... BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients with superior vena cava syndrome(SVCS).We report the case of a patient with a lower extremity PICC ectopic to the ascending lumbar vein,to indicate and verify PICC catheterisation in the lower extremity is safe and feasible.And hope to provide different per-spectives for clinical PICC venipuncture to get the attention of peers.CASE SUMMARY On 24 August 2022,a 58-year-old male was admitted to our department due to an intermittent cough persisting for over a month,which worsened 10 d prior.Imaging and laboratory investigations suggested the patient with pulmonary malignancy and SVCS.Chemotherapy was not an absolute contraindication in this patient.Lower extremity venipuncture is the preferred technique because administering upper extremity venous transfusion to patients with SVCS can exacerbate oedema in the head,neck,and upper extremities.The patient and his family were informed about the procedure,and informed consent was obtained.After successful puncture and prompt treatment,the patient was discharged,experiencing some relief from symptoms.CONCLUSION Inferior vena cava catheterisation is rare and important for cancer patients with SVCS,particularly in complex situations involving ectopic placement. 展开更多
关键词 Superior vena cava syndrome Peripherally inserted central catheter Ascending lumbar vein COMPLICATIONS Case report
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Position and complications of pedicle screw insertion with or without image-navigation techniques in the thoracolumbar spine:a meta-analysis of comparative studies 被引量:16
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作者 Jinshan Tang Ziqiang Zhu +2 位作者 Tao Sui Dechao Kong Xiaojian Cao 《The Journal of Biomedical Research》 CAS 2014年第3期228-239,共12页
Computer-navigated pedicle screw insertion is applied to the thoracic and lumbar spine to attain high insertion accuracy and a low rate of screw-related complications.However,some in vivo and in vitro studies have sho... Computer-navigated pedicle screw insertion is applied to the thoracic and lumbar spine to attain high insertion accuracy and a low rate of screw-related complications.However,some in vivo and in vitro studies have shown that no advantages are gained with the use of navigation techniques compared to conventional techniques.Additionally,inconsistent conclusions have been drawn in various studies due to different population characteristics and methods used to assess the accuracy of screw placement.Moreover,it is not clear whether pedicle screw insertion with navigation techniques decreases the incidence of screw-related complications.Therefore,this study was sought to perform a meta-analysis of all available prospective evidence regarding pedicle screw insertion with or without navigation techniques in human thoracic and lumbar spine.We considered in vivo comparative studies that assessed the results of pedicle screw placement with or without navigation techniques.PubMed,Ovid MEDLINE and EMBASE databases were searched.Three published randomized controlled trials(RCTs) and nine retrospective comparative studies met the inclusion criteria.These studies included a total of 732 patients in whom 4,953 screws were inserted.In conclusion,accuracy of the position of grade I,II,III and IV screws and complication rate related to pedicle screw placement were significantly increased when navigation techniques were used in comparison to conventional techniques.Future research in this area should include RCTs with well-planned methodology to limit bias and report on validated,patient-based outcome measures. 展开更多
关键词 META-ANALYSIS POSITION pedicle screw insertion navigation COMPLICATION
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Does flexible small-diameter colonoscope reduce insertion pain during colonoscopy? 被引量:7
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作者 Yoshiharu Uno Akihiro Munakata 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期659-663,共5页
AIM It is well known that colonoscopy can bedifficult due to abdominal pain induced duringcolonoscope insertion,if sedative agents are notgiven.Recently,an extra-flexible,small-diameter colonoscope(CF-SV,Olympus Inc.,... AIM It is well known that colonoscopy can bedifficult due to abdominal pain induced duringcolonoscope insertion,if sedative agents are notgiven.Recently,an extra-flexible,small-diameter colonoscope(CF-SV,Olympus Inc.,Japan)was developed in order to improve safetyand comfort.The aim of this study was toaccess the usefulness of the CF-SV.METHODS One hundred patients undergoingsigmoidoscopy were recruited and colonoscopywas performed by one experiencedcolonoscopist.First,a routine-type colonoscope(CF-2301)was inserted into the colon withoutsedation.When the patient complained ofabdominal pain(even if mild),the scope wasnot advanced further and was withdrawn afterthe anatomic location of its tip was determinedfluoroscopically.Then,the CF-SV was inserteduntil it reached the cecun or the site whereabdominal pain occurred.Previous abdominalsurgery and abdominal disease were consideredas unfavorable factors(UF)and the relationshipbetween abdominal pain and UF,age and genderwere investigated.Furthermore,the colonicinsertion pressures in 36 patients with abdominalpain were measured with a force gauge.RESULTS Thirty-four cases(34%)felt no painwith the CF-2301 and successful pancolon-0scopies to the cecum were performed.Sixty-six cases(66%)complained of abdominal pain.The procedure was painless for 47% of men and24% of women,respectively.The CF-2301 scopefailed to reach the sigmoid-descending colon junctions in 59(89.4%)of the 66 patientscomplaining of abdominal pain.However,CF-SVreached proximal area in 94.9% of those whofailed with CF-2301.The median pressure forpain-inducing was 700 g/cm^2.CONCLUSION Unsedated patients with UFwere prone to complain of pain when thestandard-type CF-2301 scope was used.Thenewly developed extra-flexible CF-SV is usefulfor the aged and for those with UF or being proneto suffer from abdominal pain.Sedative agentsmay be unnecessary if this new type ofcolonoscope is used. 展开更多
关键词 COLONOSCOPY ABDOMINAL PAIN FLEXIBLE colonoscope insertion pressure unfavorable factors SIGMOIDOSCOPY
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An Analysis of the Orthogonal Crank-rocking Lever Spatial Mechanism for the Weft Insertion in Rapier Looms 被引量:6
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作者 Li Kerang(李克让) +1 位作者 Chen Ming(陈明) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期27-31,共5页
On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are stu... On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are studied when the maximum swing angle of rocking lever and the length of outputting lever have different values, and the optimum parameters suitable for motion transmission can be chosen. At the same time some existing shortpoints of the mechanism are also pointed out. 展开更多
关键词 RAPIER loom WEFT insertion mechanism motion transmission performance.
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Kinematic Modeling and Characteristic Analysis of Eccentric Conjugate Non-circular Gear & Crank-Rocker & Gears Train Weft Insertion Mechanism 被引量:7
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作者 陈建能 赵华成 +2 位作者 王英 徐高欢 周鸣 《Journal of Donghua University(English Edition)》 EI CAS 2013年第1期15-20,共6页
A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's wef... A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's weft insertion mechanism as well as reduce the manufacturing difficulty. Meanwhile, based on the working principle of this mechanism, kinematical mathematic models of this mechanism were established and an aided analysis and simulation software was compiled. The influences of eccentricity ratio, deformation coefficient, and other important parameters on the kinematics characteristics of this mechanism were analyzed by using the software. A group of preferable parameters which could meet the requirements of weft insertion technology were obtained by means of human-computer interactive optimization method. The maximum velocity, maximum acceleration, and variation of acceleration of this mechanism are smaller than those of the conjugate cam weft insertion mechanism applied on TT96 rapier loom under the conditions of the same unilateral total stroke of rapier head and the same rotary speed of loom spindle; meanwhile the other demands of weaving technology can be met by this novel weft insertion mechanism. 展开更多
关键词 weft insertion mechanism eccentric conjugate non-circular gear crank-rocker KINEMATICS
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Angiotensin-converting Enzyme Gene Insertion/Deletion Polymorphism in Children with Henoch-Schonlein Purpua Nephritis 被引量:17
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作者 周建华 田雪飞 徐钦儒 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第2期158-161,共4页
This study investigated the relationship between angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism and the occurrence, severity, prognosis of HSPN. The polymorphism of ACE gene in 103 HSPN case... This study investigated the relationship between angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism and the occurrence, severity, prognosis of HSPN. The polymorphism of ACE gene in 103 HSPN cases and 100 healthy children was studied by using the polymerase chain reactions (PCR). Its relation to the clinical manifestation, pathological classification and prognosis of HSPN was analyzed accordingly. The results showed that: (1) there was a significantly higher frequency for DD genotype in HSPN children (P<0.01); (2) DD genotype was more frequently seen in HSPN children with gross hematuria and massive proteinuria (P<0.05), while DI genotype was more common in HSPN children group with renal insufficiency (P<0.05); (3) although mesangial proliferative lesion was most frequently observed in 21 biopsied HSPN children, and DD genotype frequency was still higher in children with severe pathology (Class Ⅲ Ⅳ); (4)II genotype was significantly frequent in HSPN children with complete remission in the follow-up of 32 HSPN children. It was concluded that the deletion allele of ACE gene might play a role, at least to some extent, in the occurrence, deterioration and progression in juvenile HSPN. 展开更多
关键词 angiotensin-converting enzyme gene insertion/deletion polymorphism Henoch-Schonlein purura nephritis children
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