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Surgical specimen extraction via a prophylactic ileostomy procedure: A minimally invasive technique for laparoscopic rectal cancer surgery

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World Journal of Gastroenterology 2018年第1期24卷 104-111页

作者： Peng Wang Jian-Wei Liang Hai-Tao zhou Zheng Wang Zhi-Xiang Zhou Department of Colorectal Surgery National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College

AIM To retrospectively evaluate the safety and feasibility of surgical specimen extraction via a prophylactic ileostomy procedure in patient with rectal cancer. METHODS We systematically reviewed 331 consecutive patients who underwent laparoscopic anterior resection for rectal cancer and prophylactic ileostomy in our institution from June 2010 to October 2016, including 155 patients who underwent specimen extraction via a prophylactic ileostomy procedure(experimental group), and 176 patients who underwent specimen extraction via a small lower abdominal incision(control group). Clinical data were collected from both groups andstatistically analyzed. RESULTS The two groups were matched in clinical characteristics and pathological outcomes. However, mean operative time was significantly shorter in the experimental group compared to the control group(161.3 ± 21.5 min vs 168.8 ± 20.5 min; P = 0.001). Mean estimated blood loss was significantly less in the experimental group(77.4 ± 30.7 mL vs 85.9 ± 35.5 mL; P = 0.020). The pain reported by patients during the first two days after surgery was significantly less in the experimental group than in the control group. No wound infections occurred in the experimental group, but 4.0% of the controls developed wound infections(P = 0.016). The estimated 5-year disease-free survival and overall survival rate were similar between the two groups.CONCLUSION Surgical specimen extraction via a prophylactic ileostomy procedure represents a secure and feasible approach to laparoscopic rectal cancer surgery, and embodies the principle of minimally invasive surgery.

关键词： Minimally invasive surgery Rectal cancer Anastomotic leakage Prophylactic ileostomy Safety

Segregation of solute atoms in ZrC grain boundaries and their effects on grain boundary strengths

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Journal of Materials Science & Technology 2022年第6期101卷 234-241页

作者： Fu-zhi Dai Yinjie Sun Yixiao Ren Huimin xiang Yanchun zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

ZrC is a promising candidate for the application in ultra-high temperature regime due to its unique combination of excellent properties,such as high melting point,good chemical inertness and high temperature stability.The rapid decrease of strength at high temperatures,however,is one of the obstacles that impedes its practical services.Strengthening of grain boundaries by solute segregation is believed to be an effective way to improve its high temperature performance.Therefore,the segregation tendency of ten solid solute atoms,including Sc,Ti,V,Cr,Y,Nb,Mo,Hf,Ta,W,in Zr C grain boundaries,and the strengthening/weakening effects on grain boundaries due to segregation are investigated by first-principles calculations.The segregation tendency is found dominated by the size effect,which is confirmed by both a qualitative analysis and a quantitative approach based on support vector regression.It means that big atoms tend to segregate to grain boundary sites with local expansions,while small atoms tend to segregate to grain boundary sites with local compressions.Simulations on stress-strain responses indicate that segregation of small atoms(Ti,V,Cr,Nb,Ta,Mo,W)can usually improve grain boundary strengths by inducing compression strains to grain boundaries,even though there is also an exception.In contrast,segregation of Sc and Y will soften grain boundaries.The results reveal that strengthening of grain boundaries by solute segregation is a valuable avenue to enhance high temperature mechanical properties of ZrC,providing guidelines for further design of ZrC based materials.

关键词： ZrC Grain boundary Segregation Strength First-principles calculation Machine learning

Short-term outcomes of overlapped delta-shaped anastomosis, an innovative intracorporeal anastomosis technique, in totally laparoscopic colectomy for colon cancer

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World Journal of Gastroenterology 2017年第36期23卷 6726-6732页

作者： Hai-Tao zhou Peng Wang Jian-Wei Liang Hao Su Zhi-Xiang Zhou Department of Colorectal Surgery National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021

AIM To introduce an innovative intracorporeal anastomosis technique named overlapped delta-shaped anastomosis(ODA)for colon cancer cases undergoing totally laparoscopic colectomy(TLC)and to assess its feasibility and safety. METHODS From January 2016 to March 2017,a total of 20consecutive patients with colon cancer accepted TLC and the ODA technique at our medical center.Patient demographics,operative outcomes,perioperative complications,and pathological results were collected and analyzed. RESULTS We successfully completed TLC and the ODA procedure in all 20 cases,including 6(30%)males and 14(70%)females.In total,11(55%),2(10%),and 7(35%)cases accepted right hemicolectomy,transverse hemicolectomy,and left hemicolectomy,respectively.None of the surgeries were converted to an open operation.Mean operative time was 178.5 min,and mean estimated blood loss was 58.5 m L.Mean time to first flatus was 2.5 d,and mean postoperative hospitalization duration was 6.8 d.No severe complications occurred,such as anastomotic leakage,snastomotic stenosis,anastomotic bleeding,and wound infection,except for one case who suffered from an abdominal infection and another case who suffered from gastric paralysis syndrome.Tumor recurrence was not observed in any patient during the follow-up period. CONCLUSION The ODA technique for colon cancer cases undergoing TLC appears to be safe and feasible,although our current results need to be verified in further studies.

关键词： Overlapped delta-shaped anastomosis Safety Totally laparoscopic colectomy Intracorporeal anastomosis Colon cancer

Y_5Si_3C and Y_3Si_2C_2: Theoretically predicted MAX phase like damage tolerant ceramics and promising interphase materials for SiC_f/SiC composites

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Journal of Materials Science & Technology 2019年第3期35卷 313-322页

作者： Yanchun zhou Huimin xiang Fu-zhi Dai Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials & Processing Technology

Researching for interphase materials that can protect SiC fibers from oxygen and water vapor attacks has become one of the most important issues for the applications of SiC_f/SiC composites in high-temperature combustion environment. However, such kinds of interphase materials are not available yet. Herein,we report theoretically predicted properties of two promising interphase materials Y_5Si_3 C and Y_3Si_2C_2.Although crystallizing in different structures, they share the common features of layered structure,anisotropic chemical bonding, anisotropic electrical and mechanical properties, and low shear deformation resistance. The bulk moduli for Y_5Si_3C and Y_3Si_2C_2 are 78 and 93 GPa, respectively; while their shear moduli are 52 and 50GPa, respectively. The maximum to minimum Young's modulus ratios are1.44 for Y_5Si_3C and 3.27 for Y_3Si_2C_2. Based on the low shear deformation resistance and low Pugh's ratios(G/B = 0.666 forY_5Si_3C and 0.537 for Y_3Si_2C_2; G: shear modulus; B: bulk modulus), they are predicted as damage tolerant and soft ceramics with predicted Vickers hardness of 9.6 and 6.9 GPa, respectively.The cleavage plane and possible slip systems are(000 l) and(0001)[1120] and(1010)[0001] forY_5Si_3C,and those for Y_3Si_2C_2 are {h00} and(010)[101]. Since the oxidation products are water-vapor resistant Y2 Si2 O7, Y2 SiO5 and/or Y_2 O_3 upon oxidation, and the volume expansions are ca 140% and ca 26% for Y_5Si_3C and Y_3Si_2C_2, they are expected to seal the interfacial cracks in SiC_f/SiC composites. The unique combination of easy cleavage, low shear deformation resistance, volume expansions upon oxidation, and the resistance of the oxidation products to water vapor attack warrant them promising as interphase materials of SiC_f/SiC composites for water-vapor laden environment applications.

关键词： Y5Si3C Y3Si2C2 Interphase material Damage tolerant ceramics Electronic structure

Theoretical investigation on the stability, mechanical and thermal properties of the newly discovered MAB phase Cr4AlB4

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Journal of Materials Science & Technology 2020年第4期39卷 161-166页

作者： Fu-zhi Dai Haiming Zhang Huimin xiang Yanchun zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing100076China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China

The nanolaminated MAB phases have attracted great research interests in recent years due to their similarities to MAX phases,which display both metallic and ceramic-like properties.In the present work,a newly discovered MAB phase Cr4AlB4 was investigated by first principles calculations.Energy evaluations indicate that Cr4AlB4 can be synthetized in Al lean condition,which can further transform to Cr2AlB2 in Al rich condition.The full set of elastic properties and their dependences on temperature,ideal strengths under different tensile and shear deformations,and thermal expansions of Cr4AlB4 were predicted.The results reveal that the properties of Cr4AlB4 are dominated by the layered crystal structure and weak bonding nature between Al and Cr2B2 layers,including low elastic stiffness and large thermal expansion along[010]direction(the stacking direction of Al and Cr2B2 layers),low shear resistances in(010)plane,and preferentially cleavage along and/or shear in(010)plane.Therefore,it suggests that Cr4AlB4 displays similar mechanical properties to MAX phases,including readily machinable,thermal shock resistant,and damage tolerant.In combination with the fact that Cr,Al and B all can form dense oxides to protect the material from further oxidation,Cr4AlB4 is regarded as a promising high temperature ceramic.

关键词： MAB phase Cr4AlB4 First-principles Mechanical properties Thermal properties

Clinicopathological characteristics and prognostic factors for the recurrence of abdominal desmoid tumors: a retrospective study of 113 patients from two Chinese hospitals

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Chinese Medical Journal 2021年第12期134卷 1505-1507页

作者： Si-Cheng zhou Wei Pei Zhen Sun Zhi-Xiang Zhou Xi-Shan Wang Jian-Wei Liang Qiang Feng Department of Colorectal Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of General Surgery Beijing HospitalBeijing 100730China

To the Editor:Desmoid tumors(DTs)show local aggressiveness to surrounding structures and exhibit a propensity to recur,leading to a high local recurrence rate and significant functional impairments and morbidity.[1]It has been shown that DTs located in the abdominal wall and abdominal cavity are relatively minimally invasive and have a relatively low recurrence rate,[2]which indicated abdominal desmoid tumors(ADTs)may have different biological make-ups and genes.This study was aimed to delineate the clinicopathological features and determine the prognostic factors for recurrence-free survival(RFS)in ADTs after macroscopic complete surgical resection.

关键词： abdominal tumors patients

Achieving ultra-broadband electromagnetic wave absorption in high-entropy transition metal carbides (HE TMCs)

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Journal of Advanced Ceramics 2022年第4期11卷 545-555页

作者： Weiming ZHANG Huimin xiang Fu-zhi DAI Biao ZHAO Shijiang WU Yanchun zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China Zibo Firststar New Material Incorporated Co. Ltd.Zibo 255000China

Electronic devices pervade everyday life,which has triggered severe electromagnetic(EM)wave pollution.To face this challenge,developing EM wave absorbers with ultra-broadband absorption capacity is critically required.Currently,nano-composite construction has been widely utilized to realize impedance match and broadband absorption.However,complex experimental procedures,limited thermal stability,and interior oxidation resistance are still unneglectable issues.Therefore,it is appealing to realize ultra-broadband EM wave absorption in single-phase materials with good stability.Aiming at this target,two high-entropy transition metal carbides(HE TMCs)including(Zr,Hf,Nb,Ta)C(HE TMC-2)and(Cr,Zr,Hf,Nb,Ta)C(HE TMC-3)are designed and synthesized,of which the microwave absorption performance is investigated in comparison with previously reported(Ti,Zr,Hf,Nb,Ta)C(HE TMC-1).Due to the synergistic effects of dielectric and magnetic losses,HE TMC-2 and HE TMC-3 exhibit better impedance match and wider effective absorption bandwidth(EAB).In specific,the exclusion of Ti element in HE TMC-2 endows it optimal minimum reflection loss(RL_(min))and EAB of−41.7 dB(2.11 mm,10.52 GHz)and 3.5 GHz(at 3.0 mm),respectively.Remarkably,the incorporation of Cr element in HE TMC-3 significantly improves the impedance match,thus realizing EAB of 10.5,9.2,and 13.9 GHz at 2,3,and 4 mm,respectively.The significance of this study lays on realizing ultra-broadband capacity in HE TMC-3(Cr,Zr,Hf,Nb,Ta),demonstrating the effectiveness of high-entropy component design in tailoring the impedance match.

关键词： transition metal carbide(TMC) high-entropy ceramics electromagnetic(EM)wave absorption dielectric and magnetic loss coupling ultra-broadband absorption

Grain boundary segregation induced strong UHTCs at elevated temperatures:A universal mechanism from conventional UHTCs to high entropy UHTCs

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Journal of Materials Science & Technology 2022年第28期123卷 26-33页

作者： Fu-zhi Dai Bo Wen Yinjie Sun Yixiao Ren Huimin xiang Yanchun zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China DP Technology Beijing 100044China

Ultra-high temperature ceramics(UHTCs)exhibit a unique combination of excellent properties,including ultra-high melting point,excellent chemical stability,and good oxidation resistance,which make them promising candidates for aerospace and nuclear applications.However,the degradation of hightemperature strength is one of the main limitations for their ultra-high temperature applications.Thus,searching for mechanisms that can help to develop high-performance UHTCs with good high-temperature mechanical properties is urgently needed.To achieve this goal,grain boundary segregation of a series of carbides,including conventional,medium entropy,and high entropy transition metal carbides,i.e.,Zr_(0.95)W_(0.05)C,TiZrHfC_(3),ZrHfNbTaC_(4),TiZrHfNbTaC_(5),were studied by atomistic simulations with a fitted Deep Potential(DP),and the effects of segregation on grain boundary strength were emphasized.For all the studied carbides,grain boundary segregations are realized,which are dominated by the atomic size effect.In addition,tensile simulations indicate that grain boundaries(GBs)will usually be strengthened due to segregation.Our simulation results reveal that grain boundary segregation may be a universal mechanism in enhancing the high-temperature strength of both conventional UHTCs and medium/high entropy UHTCs,since GBs play a key role in controlling the fracture of UHTCs at elevated temperatures.

关键词： UHTCs High entropy ceramics Grain boundary segregation High-temperature strength Machine learning potential

Digital twin-driven green material optimal selection and evolution in product iterative design

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Advances in Manufacturing 2023年第4期11卷 647-662页

作者： Feng xiang Ya-Dong zhou zhi Zhang Xiao-Fu Zou Fei Tao Ying Zuo Key Laboratory of Metallurgical Equipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081People’s Republic of China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081People’s Republic of China Institute of Artificial Intelligence Beihang UniversityBeijing100191People’s Republic of China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191People’s Republic of China Research Institute for Frontier Science Beihang UniversityBeijing100191People’s Republic of China

In recent years,green concepts have been integrated into the product iterative design in the manufacturing field to address global competition and sustainability issues.However,previous efforts for green material optimal selection disregarded the interaction and fusion among physical entities,virtual models,and users,resulting in distortions and inaccuracies among user,physical entity,and virtual model such as inconsistency among the expected value,predicted simulation value,and actual performance value of evaluation indices.Therefore,this study proposes a digital twin-driven green material optimal selection and evolution method for product iterative design.Firstly,a novel framework is proposed.Subsequently,an analysis is carried out from six perspectives:the digital twin model construction for green material optimal selection,evolution mechanism of the digital twin model,multi-objective prediction and optimization,algorithm design,decision-making,and product function verification.Finally,taking the material selection of a shared bicycle frame as an example,the proposed method was verified by the prediction and iterative optimization of the carbon emission index.

关键词： Product iterative design Digital twin(DT) Green material optimal selection Evolution mechanism Iterative optimization