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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy
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作者 Junjie Li Wenbo Yu +5 位作者 Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期147-153,共7页
High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress aro... High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated die-castings.Herein,the development of non-heat treatment Al alloys is becoming the hot topic.In addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of castings.To achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and Ce.Their influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic simulation.Our results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased porosity.Meanwhile,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical properties.Subsequent introduction of Ce resulted in the poisoning effect and reduced mechanical properties. 展开更多
关键词 aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment
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Bioinspired Ultrasensitive Flexible Strain Sensors for Real‑Time Wireless Detection of Liquid Leakage
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作者 Weilong Zhou Yu Du +6 位作者 Yingying Chen Congyuan Zhang Xiaowei Ning Heng Xie Ting Wu Jinlian Hu Jinping Qu 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期310-327,共18页
Liquid leakage of pipeline networks not only results in considerableresource wastage but also leads to environmental pollution and ecological imbalance.In response to this global issue, a bioinspired superhydrophobic ... Liquid leakage of pipeline networks not only results in considerableresource wastage but also leads to environmental pollution and ecological imbalance.In response to this global issue, a bioinspired superhydrophobic thermoplastic polyurethane/carbon nanotubes/graphene nanosheets flexible strain sensor (TCGS) hasbeen developed using a combination of micro-extrusion compression molding andsurface modification for real-time wireless detection of liquid leakage. The TCGSutilizes the synergistic effects of Archimedean spiral crack arrays and micropores,which are inspired by the remarkable sensory capabilities of scorpions. This designachieves a sensitivity of 218.13 at a strain of 2%, which is an increase of 4300%. Additionally, it demonstrates exceptional durability bywithstanding over 5000 usage cycles. The robust superhydrophobicity of the TCGS significantly enhances sensitivity and stability indetecting small-scale liquid leakage, enabling precise monitoring of liquid leakage across a wide range of sizes, velocities, and compositionswhile issuing prompt alerts. This provides critical early warnings for both industrial pipelines and potential liquid leakage scenariosin everyday life. The development and utilization of bioinspired ultrasensitive flexible strain sensors offer an innovative and effectivesolution for the early wireless detection of liquid leakage. 展开更多
关键词 Thermoplastic polyurethane BIOINSPIRED Cracks Liquid leakage Flexible strain sensor
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Numerical and experimental investigation of leakage behavior at null position of high-pressure electro-pneumatic servo valve 被引量:2
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作者 ZHANG Di-jia GAO Long-long +2 位作者 WU Chuan ZHAO Zhi-xin LI Bao-ren 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3117-3126,共10页
The high-pressure electro-pneumatic servo valve(HESV)is a core element of the high-pressure pneumatic servo system.The annular clearance and the rounded corner of the spool-sleeve can cause the leakage at null positio... The high-pressure electro-pneumatic servo valve(HESV)is a core element of the high-pressure pneumatic servo system.The annular clearance and the rounded corner of the spool-sleeve can cause the leakage at null position,thereby affecting high-precision control and stability of the servo system.This paper investigates the effects of the clearance structure on leakage behavior at null position of the HESV.A numerical approach was employed to evaluate the effects,and then a mathematical model was established to obtain the variation law of leakage flow rate at null position.The results indicate that the leakage flow rate at null position varies linearly with supply pressure and rounded corner radius,and is nonlinear as a quadratic concave function with annular clearance.The leakage flow rate of the annular clearance and the rounded corner varies with the valve opening in an invariable−nonlinear−linear trend.A test rig system of leakage behavior at null position of the HESV was built to confirm the validity of the numerical model,which agrees well with the conducted experimental study. 展开更多
关键词 high-pressure electro-pneumatic servo valve CLEARANCE leakage flow rate null position
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Effect of stress-dependent microannulus aperture on well leakage 被引量:1
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作者 Meng Meng Luke P.Frash +3 位作者 J.William Carey Mohamed Mehana Wenfeng Li Bailian Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1967-1976,共10页
Debonding at the cement-casing interface is recognized as a principal failure mechanism leading to CO_(2) leakage in wells.This detachment gives rise to a microannulus,which notably possesses greater permeability than... Debonding at the cement-casing interface is recognized as a principal failure mechanism leading to CO_(2) leakage in wells.This detachment gives rise to a microannulus,which notably possesses greater permeability than undamaged cement,undermining its sealing efficacy.Conventionally,the permeability of the microannulus is regarded as a uniform value throughout the well.However,fundamentally,a microannulus is one type of fracture,and its gap or aperture size is affected by the effective stress.In this work,we developed a unique experimental apparatus.This equipment facilitates the curing of cement inside a steel casing,the formation of a microannulus between the casing and the cement,and the investigation of the fluid flow dynamics along the microannulus under laboratory-replicated in situ conditions.The microannulus was formed by injecting fluid from one end of the setup,and receiving similar amount of fluid on the other end signified the development of the leakage channel.Additionally,strain gauges affixed to the casing’s external surface yielded key information on the microannulus’s opening and closure.We observed a noticeable decline in microannulus hydraulic aperture(or permeability)in relation to effective stress and an exponential equation fits their relationship.Our findings also indicate a distinct behavior when comparing liquid CO_(2) with water.Specifically,it is easier for liquid CO_(2) to create the microannulus.However,the hydraulic aperture range for this microannulus(0.7-6 mm)is considerably smaller than that created by water flow(2-17 mm).Finally,we integrated the stressdependent microannulus aperture size into the combined analysis of well mechanical integrity and well leakage.The outcomes consistently demonstrated that when factoring in the stress-dependent aperture sizes,the leakage rates are 3e5 times compared to a fixed aperture model.The traditional assumption of a constant aperture significantly underestimates fluid leakage risks. 展开更多
关键词 Microannulus leakage assessment Aperture size Triaxial experiment Carbon sequestration
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Evaluating Privacy Leakage and Memorization Attacks on Large Language Models (LLMs) in Generative AI Applications 被引量:1
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作者 Harshvardhan Aditya Siddansh Chawla +6 位作者 Gunika Dhingra Parijat Rai Saumil Sood Tanmay Singh Zeba Mohsin Wase Arshdeep Bahga Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2024年第5期421-447,共27页
The recent interest in the deployment of Generative AI applications that use large language models (LLMs) has brought to the forefront significant privacy concerns, notably the leakage of Personally Identifiable Infor... The recent interest in the deployment of Generative AI applications that use large language models (LLMs) has brought to the forefront significant privacy concerns, notably the leakage of Personally Identifiable Information (PII) and other confidential or protected information that may have been memorized during training, specifically during a fine-tuning or customization process. We describe different black-box attacks from potential adversaries and study their impact on the amount and type of information that may be recovered from commonly used and deployed LLMs. Our research investigates the relationship between PII leakage, memorization, and factors such as model size, architecture, and the nature of attacks employed. The study utilizes two broad categories of attacks: PII leakage-focused attacks (auto-completion and extraction attacks) and memorization-focused attacks (various membership inference attacks). The findings from these investigations are quantified using an array of evaluative metrics, providing a detailed understanding of LLM vulnerabilities and the effectiveness of different attacks. 展开更多
关键词 Large Language Models PII leakage Privacy Memorization OVERFITTING Membership Inference Attack (MIA)
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Nano-scale Reinforcements and Properties of Al-Si-Cu Alloy Processed by High-Pressure Torsion
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作者 DONG Ying WU Siyuan +4 位作者 HE Ziyang LIANG Chen CHENG Feng HE Zuwei QIAN Chenhao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1253-1259,共7页
To improve the comprehensive mechanical properties of Al-Si-Cu alloy,it was treated by a high-pressure torsion process,and the effect of the deformation degree on the microstructure and properties of the Al-Si-Cu allo... To improve the comprehensive mechanical properties of Al-Si-Cu alloy,it was treated by a high-pressure torsion process,and the effect of the deformation degree on the microstructure and properties of the Al-Si-Cu alloy was studied.The results show that the reinforcements(β-Si andθ-CuAl_(2)phases)of the Al-Si-Cu alloy are dispersed in theα-Al matrix phase with finer phase size after the treatment.The processed samples exhibit grain sizes in the submicron or even nanometer range,which effectively improves the mechanical properties of the material.The hardness and strength of the deformed alloy are both significantly raised to 268 HV and 390.04 MPa by 10 turns HPT process,and the fracture morphology shows that the material gradually transits from brittle to plastic before and after deformation.The elements interdiffusion at the interface between the phases has also been effectively enhanced.In addition,it is found that the severe plastic deformation at room temperature induces a ternary eutectic reaction,resulting in the formation of ternary Al+Si+CuAl_(2)eutectic. 展开更多
关键词 Al-Si-Cu alloy high-pressure torsion nano-scale reinforcements ternary eutectic
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Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite
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作者 Seyed Mohammad Reza Abtahi Saeid Ansari Sadrabadi +4 位作者 Gholam Hosein Rahimi Gaurav Singh Hamid Abyar Daniele Amato Luigi Federico 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1783-1806,共24页
Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necess... Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necessary strength.Therefore,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME B31.G.In addition,the experimental tests are replicated numerically using the finite element method.Setting the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high pressure.The direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the defect.Composite reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed. 展开更多
关键词 high-pressure pipeline composite repair ASME PCC-2 ISO 24817
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Peritoneal fluid indocyanine green test for diagnosis of gut leakage in anastomotic leakage rats and colorectal surgery patients
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作者 Yu Huang Tian-Yang Li +4 位作者 Jie-Feng Weng Hui Liu Yu-Jie Xu Shuai Zhang Wei-Li Gu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1825-1834,共10页
BACKGROUND Application of indocyanine green(ICG)fluorescence has led to new developments in gastrointestinal surgery.However,little is known about the use of ICG for the diagnosis of postoperative gut leakage(GL).In a... BACKGROUND Application of indocyanine green(ICG)fluorescence has led to new developments in gastrointestinal surgery.However,little is known about the use of ICG for the diagnosis of postoperative gut leakage(GL).In addition,there is a lack of rapid and intuitive methods to definitively diagnose postoperative GL.AIM To investigate the effect of ICG in the diagnosis of anastomotic leakage in a surgical rat GL model and evaluate its diagnostic value in colorectal surgery patients.METHODS Sixteen rats were divided into two groups:GL group(n=8)and sham group(n=8).Approximately 0.5 mL of ICG(2.5 mg/mL)was intravenously injected postoperatively.The peritoneal fluid was collected for the fluorescence test at 24 and 48 h.Six patients with rectal cancer who had undergone laparoscopic rectal cancer resection plus enterostomies were injected with 10 mL of ICG(2.5 mg/mL)on postoperative day 1.Their ostomy fluids were collected 24 h after ICG injection to identify the possibility of the ICG excreting from the peripheral veins to the enterostomy stoma.Participants who had undergone colectomy or rectal cancer resection were enrolled in the diagnostic test.The peritoneal fluids from drainage were collected 24 h after ICG injection.The ICG fluorescence test was conducted using OptoMedic endoscopy along with a near-infrared fluorescent imaging system.RESULTS The peritoneal fluids from the GL group showed ICG-dependent green fluorescence in contrast to the sham group.Six samples of ostomy fluids showed green fluorescence,indicating the possibility of ICG excreting from the peripheral veins to the enterostomy stoma in patients.The peritoneal fluid ICG test exhibited a sensitivity of 100%and a specificity of 83.3%for the diagnosis of GL.The positive predictive value was 71.4%,while the negative predictive value was 100%.The likelihood ratios were 6.0 for a positive test result and 0 for a negative result.CONCLUSION The postoperative ICG test in a drainage tube is a valuable and simple technique for the diagnosis of GL.Hence,it should be employed in clinical settings in patients with suspected GL. 展开更多
关键词 Gut leakage Indocyanine green Anastomotic leakage model Diagnostic test Diagnostic technique
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Far-Field Behavior of Supercritical CO_(2)Being Dispersed Due to Leakage from Pipelines
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作者 Yanbo Shao Xuewen Cao +3 位作者 Wei You Shan Zhao Zilong Nan Jiang Bian 《Fluid Dynamics & Materials Processing》 EI 2024年第12期2867-2885,共19页
Transporting massive quantities of carbon dioxide through a pipeline in its supercritical state is extremely convenient.Because of the unique properties of supercritical carbon dioxide,however,leakage occurring in suc... Transporting massive quantities of carbon dioxide through a pipeline in its supercritical state is extremely convenient.Because of the unique properties of supercritical carbon dioxide,however,leakage occurring in such conditions can be extremely intricate,resulting in the dispersion area following leakage being influenced by numerous factors.In this study,this problem is addressed in the frame of the so-called Unified Dispersion Model(UDM),and various influential parameters are considered,namely,leakage pressure,leakage temperature,leakage aperture,leakage angle,atmospheric stability,wind speed,and surface roughness.The results show that the supercritical carbon dioxide dispersion is primarily influenced by high air temperatures,low wind speeds,reduced surface roughness,and release temperatures slightly below the critical temperature.Additionally,leak apertures also contribute to the dispersion.The dispersion is maximized under atmospheric stable D conditions,and when the leakage angle is 0°,the farthest downwind distance is 10 times greater than that at a leakage angle of 90°under the same conditions. 展开更多
关键词 Supercritical carbon dioxide leakage DISPERSION PIPELINE
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Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy
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作者 Dongfei Lu Guoqiang Xi +5 位作者 Hangren Li Jie Tu Xiuqiao Liu Xudong Liu Jianjun Tian Linxing Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2263-2273,共11页
BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric p... BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric properties.Herein,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were invest-igated.Results confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based films.Sm and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward pseudo-tet-ragonal.Piezoelectric force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared films.The ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mn<Cu<Co(B-site),La<Eu<Sm(A-site).Scanning electron microscopy showed that the introduction of Cu elements facilitates the formation of dense grains,and the grain size distribution statistics proved that La element promotes the reduction of grain size,leading to the increase of grain boundaries and the reduction of leakage.Finally,a Bi_(0.985)Sm_(0.045)La_(0.03)Fe_(0.96)Co_(0.02)Cu_(0.02)O_(3)(SmLa-CoCu)thin film with a qualitative leap in the remnant polarization from 25.5(Bi_(0.985)Sm_(0.075)FeO_(3))to 98.8µC/cm^(2)(SmLa-CoCu)was prepared through the syner-gistic action of Sm,La,Co,and Cu elements.The leakage current is also drastically reduced from 160 to 8.4 mA/cm^(2)at a field strength of 150 kV/cm.Thus,based on the increasing entropy strategy of chemical engineering,this study focuses on enhancing ferroelectricity and decreasing leakage current,providing a promising path for the advancement of ferroelectric devices. 展开更多
关键词 increasing entropy SYNERGISTIC ferroelectric film remnant polarization leakage current
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Side-Channel Leakage Analysis of Inner Product Masking
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作者 Yuyuan Li Lang Li Yu Ou 《Computers, Materials & Continua》 SCIE EI 2024年第4期1245-1262,共18页
The Inner Product Masking(IPM)scheme has been shown to provide higher theoretical security guarantees than the BooleanMasking(BM).This scheme aims to increase the algebraic complexity of the coding to achieve a higher... The Inner Product Masking(IPM)scheme has been shown to provide higher theoretical security guarantees than the BooleanMasking(BM).This scheme aims to increase the algebraic complexity of the coding to achieve a higher level of security.Some previous work unfolds when certain(adversarial and implementation)conditions are met,and we seek to complement these investigations by understanding what happens when these conditions deviate from their expected behaviour.In this paper,we investigate the security characteristics of IPM under different conditions.In adversarial condition,the security properties of first-order IPMs obtained through parametric characterization are preserved in the face of univariate and bivariate attacks.In implementation condition,we construct two new polynomial leakage functions to observe the nonlinear leakage of the IPM and connect the security order amplification to the nonlinear function.We observe that the security of IPMis affected by the degree and the linear component in the leakage function.In addition,the comparison experiments from the coefficients,signal-to-noise ratio(SNR)and the public parameter show that the security properties of the IPM are highly implementation-dependent. 展开更多
关键词 Side-channel analysis inner product masking mutual information nonlinear leakage
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A Case Report and Literature Review: A Case of Delayed Bile Leakage Following Laparoscopic Cholecystectomy
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作者 Shijia Li Shicheng Gong +1 位作者 Nuo Cheng Shuai Wang 《Journal of Biosciences and Medicines》 2024年第8期210-217,共8页
Background: Delayed bile leakage after laparoscopic cholecystectomy, defined as occurring more than 72 hours after surgery, is a rare and serious complication of laparoscopic cholecystectomy, with an incidence rate of... Background: Delayed bile leakage after laparoscopic cholecystectomy, defined as occurring more than 72 hours after surgery, is a rare and serious complication of laparoscopic cholecystectomy, with an incidence rate of 0.060%. Case Declaration: This case report details a patient diagnosed with delayed bile leakage 43 days after laparoscopic cholecystectomy. The patient was discharged from our hospital after undergoing CT-guided puncture treatment, with no obvious complications identified. The patient was monitored for one year following the procedure, during which time no significant discomfort was reported. Objective: This case report is to analyse and review the clinical manifestations, diagnosis, treatment and prevention of delayed bile leakage after cholecystectomy, with reference to the relevant literature. Results: Delayed bile leakage after laparoscopic cholecystectomy can be prevented, although not eliminated. It is recommended that the operator treat the operation with caution, avoid taking risks, and adhere to careful procedures and strict separation according to the requirements. This approach is key to preventing late bile leakage in the postoperative period. 展开更多
关键词 Delayed Bile leakage TREATMENT Laparoscopic Cholecystectomy
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Serum nutritional predictive biomarkers and risk assessment for anastomotic leakage after laparoscopic surgery in rectal cancer patients
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作者 Paerhati Shayimu Maitisaidi Awula +5 位作者 Chang-Yong Wang Rexida Jiapaer Yi-Peng Pan Zhi-Min Wu Yi Chen Ze-Liang Zhao 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3142-3154,共13页
BACKGROUND Anastomotic leakage(AL)is one of the severest complications after laparoscopic surgery for middle/low rectal cancer,significantly impacting patient outcomes.Identifying reliable predictive factors for AL re... BACKGROUND Anastomotic leakage(AL)is one of the severest complications after laparoscopic surgery for middle/low rectal cancer,significantly impacting patient outcomes.Identifying reliable predictive factors for AL remains a clinical challenge.Serum nutritional biomarkers have been implicated in surgical outcomes but are un-derexplored as predictive tools for AL in this setting.Our study hypothesizes that preoperative serum levels of prealbumin(PA),albumin(ALB),and transferrin(TRF),along with surgical factors,can accurately predict AL risk.AIM To determine the predictive value of preoperative serum nutritional biomarkers for rectal cancer AL following laparoscopic surgery.METHODS In the retrospective cohort study carried out at a tertiary cancer center,we examined 560 individuals who underwent laparoscopic procedures for rectal cancer from 2018 to 2022.Preoperative serum levels of PA,ALB,and TRF were measured.We employed multivariate logistic regression to determine the independent risk factors for AL,and a predictive model was constructed and evaluated using receiver operating characteristic curve analysis.RESULTS AL occurred in 11.96%of cases,affecting 67 out of 560 patients.Multivariate analysis identified PA,ALB,and TRF as the independent risk factor,each with an odds ratio of 2.621[95%confidence interval(CI):1.582-3.812,P=0.012],3.982(95%CI:1.927-4.887,P=0.024),and 2.109(95%CI:1.162-2.981,P=0.031),respectively.Tumor location(<7 cm from anal verge)and intraoperative bleeding≥300 mL also increased AL risk.The predictive model demonstrated an excellent accuracy,achieving an area under the receiver operating characteristic curve of 0.942,a sensitivity of 0.844,and a specificity of 0.922,demonstrating an excellent ability to discriminate.CONCLUSION Preoperative serum nutritional biomarkers,combined with surgical factors,reliably predict anastomotic leakage risk after rectal cancer surgery,highlighting their importance in preoperative assessment. 展开更多
关键词 Rectal cancer Laparoscopic operation Anastomotic leakage ALBUMIN PREALBUMIN TRANSFERRIN
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Thoracic spinal cord injury and paraplegia caused by intradural cement leakage after percutaneous kyphoplasty: A case report
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作者 Zi Mao Zhi-Hong Xiong Jun-Feng Li 《World Journal of Clinical Cases》 SCIE 2024年第10期1837-1843,共7页
BACKGROUND Percutaneous kyphoplasty(PKP)is a pivotal intervention for osteoporotic fractures,pathological vertebral compression fractures,and vertebral bone tumors.Despite its efficacy,the procedure presents challenge... BACKGROUND Percutaneous kyphoplasty(PKP)is a pivotal intervention for osteoporotic fractures,pathological vertebral compression fractures,and vertebral bone tumors.Despite its efficacy,the procedure presents challenges,notably complications arising from intradural cement leakage.Timely and accurate diagnosis,coupled with emergent intervention is imperative to improve patient prognosis.This case report illuminates the intricacies and potential complications associated with PKP,emphasizing the critical need for vigilant monitoring,prompt diagnosis,and immediate intervention to mitigate adverse outcomes.CASE SUMMARY A 58-year-old male patient,experiencing a T7 osteoporosis-related pathological compression fracture,underwent PKP at a local hospital.Two weeks postprocedure,the patient developed paraplegic and dysuric symptoms,necessitating emergency decompression surgery.Gradual improvement was achieved,marked by the restoration of muscle strength,sensation,and mobility.CONCLUSION PKP Intradural cement leakage following PKP is unusual and potentially fatal.Prompt imaging examinations,urgent evaluation,and the decompression surgery are essential,which help alleviate symptoms associated with spinal damage,markedly improving the overall prognosis. 展开更多
关键词 Percutaneous kyphoplasty Intradural cement leakage COMPLICATION Decompression surgery Case report
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Onset and prognostic features of anastomotic leakage in patients undergoing radical surgery after neoadjuvant chemoradiation for rectal cancer
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作者 Lei Wang Wang-Shan Zhang Guo-Jin Huang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3710-3719,共10页
BACKGROUND Anastomotic leakage(AL)is a significant complication of rectal cancer surgery,particularly in patients undergoing neoadjuvant chemoradiotherapy.This study aimed to evaluate the onset and prognostic factors ... BACKGROUND Anastomotic leakage(AL)is a significant complication of rectal cancer surgery,particularly in patients undergoing neoadjuvant chemoradiotherapy.This study aimed to evaluate the onset and prognostic factors influencing AL in these patients and provide insights for better postoperative management.AIM To explore AL incidence in patients who underwent neoadjuvant radiotherapy for rectal cancer and evaluate influencing factors and prognosis.METHODS We retrospectively analyzed data of patients with rectal cancer who underwent neoadjuvant chemoradiotherapy post-radical surgery admitted to our hospital from January 2020 to January 2023.Postoperative AL was recorded in all patients.Among 63 patients with AL initially enrolled,2 were lost to follow-up;thus,61 patients were included in the incident group.Another 59 patients without AL were included in the non-incident group.Clinical characteristics of both groups were analyzed to identify factors affecting postoperative AL and determine prognosis.RESULTS Multivariate analysis revealed that sex,operative time,bleeding,pelvic radiation injury,and intraoperative blood transfusion were independent risk factors for postoperative AL(P<0.05).The Swiss Institute for Experimental Cancer Research(ISREC)grades for patients with postoperative AL were mainly A(49.18%)and B(40.98%),and most leakages occurred in the posterior wall(65.57%).Clinical manifestations included anal sacrococaudal pain(29.51%),anal pus(26.23%),and other symptoms.Invasive interventions were performed<2 times in 80.33%of patients.Poor prognoses were mainly associated with chronic pressacral sinus formation(24.59%),anastomotic stenosis(29.51%),and long-term stoma(19.67%).Multivariate analysis revealed distance from the anal margin and ISREC grade as independent risk factors for poor prognosis following AL(P<0.05).CONCLUSION Sex,operative time,bleeding loss,pelvic radiation damage,and intraoperative blood transfusion are independent risk factors for AL and the distance between tumor and ISREC grade potentially affect prognosis. 展开更多
关键词 Neoadjuvant chemoradiotherapy Rectal cancer Radical surgery Anastomotic leakage PROGNOSIS
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CO_(2)high-pressure miscible flooding and storage technology and its application in Shengli Oilfield,China
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作者 YANG Yong ZHANG Shiming +6 位作者 CAO Xiaopeng LYU Qi LYU Guangzhong ZHANG Chuanbao LI Zongyang ZHANG Dong ZHENG Wenkuan 《Petroleum Exploration and Development》 SCIE 2024年第5期1247-1260,共14页
There are various issues for CO_(2)flooding and storage in Shengli Oilfield,which are characterized by low light hydrocarbon content of oil and high miscible pressure,strong reservoir heterogeneity and low sweep effic... There are various issues for CO_(2)flooding and storage in Shengli Oilfield,which are characterized by low light hydrocarbon content of oil and high miscible pressure,strong reservoir heterogeneity and low sweep efficiency,gas channeling and difficult whole-process control.Through laboratory experiments,technical research and field practice,the theory and technology of CO_(2)high pressure miscible flooding and storage are established.By increasing the formation pressure to 1.2 times the minimum miscible pressure,the miscibility of the medium-heavy components can be improved,the production percentage of oil in small pores can be increased,the displacing front developed evenly,and the swept volume expanded.Rapid high-pressure miscibility is realized through advanced pressure flooding and energy replenishment,and technologies of cascade water-alternating-gas(WAG),injection and production coupling and multistage chemical plugging are used for dynamic control of flow resistance,so as to obtain the optimum of oil recovery and CO_(2)storage factor.The research results have been applied to the Gao89-Fan142 in carbon capture,utilization and storage(CCUS)demonstration site,where the daily oil production of the block has increased from 254.6 t to 358.2 t,and the recovery degree is expected to increase by 11.6 percentage points in 15 years,providing theoretical and technical support for the large-scale development of CCUS. 展开更多
关键词 ow permeability reservoir CO_(2)flooding high-pressure miscibility recovery factor storage factor demonstration project
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Characteristics of gut microbiota in anastomotic leakage patients in cold zones post-colorectal cancer surgery: A high-throughput sequencing and propensity-score matching study
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作者 Yuliuming Wang Yukun Zhang +3 位作者 Yu Cao Weiyuan Zhang Ming Liu Guiyu Wang 《Frigid Zone Medicine》 2024年第2期120-128,共9页
Objective:The study aimed to explore the association between gut microbiota and anastomotic leakage(AL)after surgery in colorectal cancer(CRC)patients from a frigid zone,based on high-throughput sequencing.Methods:A t... Objective:The study aimed to explore the association between gut microbiota and anastomotic leakage(AL)after surgery in colorectal cancer(CRC)patients from a frigid zone,based on high-throughput sequencing.Methods:A total of 98 CRC patients admitted to the Second Affiliated Hospital of Harbin Medical University from July 2018 to February 2019,who met the inclusion criteria,were included.Among these,10 patients were diagnosed as AL.After propensity-score matching of baseline characteristics,10 patients from the anastomotic leakage group(AG)and 10 patients from the normal group(NG)were finally included in this study.Fecal samples were collected,and total DNA was extracted for high-throughput sequencing and bioinformatic analysis.Results:Alpha diversity analysis showed no significant difference between the two groups,while beta diversity analysis revealed significant differences in principal components.Differential microbiota were classified as Proteobacteria at the phylum level(P=0.021).At the genus level,the abundances of Streptococcus(P=0.045),Citrobacter(P=0.008)and Klebsiella(P=0.002)were significantly different between the two groups.LEfSe analysis indicated that these genera contributed most to the differences between the groups.Conclusion:The characteristics of the gut microbiota in the AG and NG were significantly different,and these differences might be associated with AL in CRC patients from frigid zones. 展开更多
关键词 colorectal cancer anastomotic leakage gut microbiota
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Endoscopic clipping of gastrojejunostomy leakage following Whipple procedure: A case report
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作者 Bahtiyar Muhammedoğlu Oguzhan Fatih Ay 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期3041-3047,共7页
BACKGROUND Currently,perioperative complications of classic Whipple surgery occur at a rate of approximately 40%.Common complications include delayed gastric emptying,pancreatic fistula,and bile leakage,whereas gastro... BACKGROUND Currently,perioperative complications of classic Whipple surgery occur at a rate of approximately 40%.Common complications include delayed gastric emptying,pancreatic fistula,and bile leakage,whereas gastrojejunostomy(GJ)leakage is rare.CASE SUMMARY This case report will assess the management of a GJ leak in a 71-year-old male patient following the Whipple procedure.After surgery,the patient was trans-ferred to the clinic after four days of intensive care,where vacuum therapy was used to handle a developing subcutaneous collection.The patient,who had bile in the drains and incision during follow-up,underwent endoscopic examination on the 21st day after the operation.An opening of approximately 4 mm was observed in the GJ anastomosis during endoscopy.Five titanium clips were used to close the openings.The drainage of bile decreased to less than 50 mL on the first day after the procedure,and the patient's oral intake was opened.CONCLUSION Current literature reports a GJ leakage rate of 0.54%following Whipple surgery,with clinical findings lasting on average between 4-34 days.Surgery was the main form of therapy for this case,with a success rate of 84%,and percutaneous drai-nage was also utilized as a treatment option.This case report is the first to docu-ment endoscopic treatment of GJ leaks following the classic Whipple procedure. 展开更多
关键词 Pancreas cancer Whipple procedure GASTROJEJUNOSTOMY leakage Endos-copic management Case report
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Enhanced mechanical and electrical properties of multi-walled carbon nanotubes reinforced Cu/Ti_(3)SiC_(2)/C nanocomposites via high-pressure torsion
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作者 Zi-xuan WU Pei-fan ZHANG +4 位作者 Xiao-song JIANG Hong-liang SUN Yan-jun LI Pål CHRISTIAN Liu YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第12期4005-4019,共15页
In order to achieve combined mechanical and electrical properties,multi-walled carbon nanotubes(MWCNTs)reinforced Cu/Ti_(3)SiC_(2)/C nanocomposites were further processed by high-pressure torsion(HPT).The maximum micr... In order to achieve combined mechanical and electrical properties,multi-walled carbon nanotubes(MWCNTs)reinforced Cu/Ti_(3)SiC_(2)/C nanocomposites were further processed by high-pressure torsion(HPT).The maximum microhardness values of central and edge from the composites with 1 wt.%MWCNTs reached HV 130.0 and HV 363.5,which were 43.9%and 39.5%higher than those of the original samples,respectively.With the same content of MWCNTs,its electrical conductivity achieved 3.42×10^(7) S/m,which was increased by 78.1%compared with that of original samples.The synergistic improvement of mechanical and electrical properties is attributed to the obtained microstructure with increased homogenization and refinement,as well as improved interfacial bonding and reduced porosity.The strengthening mechanisms include dispersion and refinement strengthening for mechanical properties,as well as reduced electron scattering for electrical properties. 展开更多
关键词 Cu/Ti_(3)SiC_(2)/C nanocomposites multi-walled carbon nanotubes high-pressure torsion microstructure MICROHARDNESS electrical conductivity
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Study of leakage current degradation based on stacking faults expansion in irradiated SiC junction barrier Schottky diodes
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作者 Maojiu Luo Yourun Zhang +5 位作者 Yucheng Wang Hang Chen Rong Zhou Zhi Wang Chao Lu Bo Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期458-464,共7页
A comprehensive investigation was conducted to explore the degradation mechanism of leakage current in SiC junction barrier Schottky(JBS)diodes under heavy ion irradiation.We propose and verify that the generation of ... A comprehensive investigation was conducted to explore the degradation mechanism of leakage current in SiC junction barrier Schottky(JBS)diodes under heavy ion irradiation.We propose and verify that the generation of stacking faults(SFs)induced by the recombination of massive electron-hole pairs during irradiation is the cause of reverse leakage current degradation based on experiments results.The irradiation experiment was carried out based on Ta ions with high linear energy transfer(LET)of 90.5 MeV/(mg/cm^(2)).It is observed that the leakage current of the diode undergoes the permanent increase during irradiation when biased at 20%of the rated reverse voltage.Micro-PL spectroscopy and PL micro-imaging were utilized to detect the presence of SFs in the irradiated SiC JBS diodes.We combined the degraded performance of irradiated samples with SFs introduced by heavy ion irradiation.Finally,three-dimensional(3D)TCAD simulation was employed to evaluate the excessive electron-hole pairs(EHPs)concentration excited by heavy ion irradiation.It was observed that the excessive hole concentration under irradiation exceeded significantly the threshold hole concentration necessary for the expansion of SFs in the substrate.The proposed mechanism suggests that the process and material characteristics of the silicon carbide should be considered in order to reinforcing against the single event effect of SiC power devices. 展开更多
关键词 4H-SiC JBS diode heavy ion irradiation single event effect single event leakage current degradation
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