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Prognostic value of 11-factor modified frailty index in postoperative adverse outcomes of elderly gastric cancer patients in China

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World Journal of Gastrointestinal Surgery 2023年第6期15卷 1093-1103页

作者： Zi-Yao Xu Xin-Yu Hao Di Wu Qi-Ying Song xin-xin Wang Department of General Surgery The First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Anesthesiology The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND Preoperative evaluation of frailty is limited to a few surgical procedures.However,the evaluation in Chinese elderly gastric cancer(GC)patients remains blank.AIM To validate and estimate the prognostic value of the 11-index modified frailty index(mFI-11)for predicting postoperative anastomotic fistula,intensive care unit(ICU)admission,and long-term survival in elderly patients(over 65 years of age)undergoing radical GC.METHODS This study was a retrospective cohort study which included patients who underwent elective gastrectomy with D2 Lymph node dissection between April 1,2017 and April 1,2019.The primary outcome was 1-year all-cause mortality.The secondary outcomes were admission to ICU,anastomotic fistula,and 6-mo mortality.Patients were divided into two groups according to the optimal grouping cutoff of 0.27 points from previous studies:High risk of frailty marked as mFI-11High and low risk of frailty marked as mFI-11Low.Survival curves between the two groups were compared,and univariate and multivariate regression analyses were performed to explore the relationship between preoperative frailty and postoperative complications in elderly patients undergoing radical GC.The discrimination ability of the mFI-11,prognostic nutritional index,and tumornode-metastasis pathological stage to identify adverse postoperative outcomes was assessed by calculating the area under the receiver operating characteristic(ROC)curve.RESULTS A total of 1003 patients were included,of which 13.86%(139/1003)were defined as having mFI-11High and 86.14%(864/1003)as having mFI-11Low.By comparing the incidence of postoperative complications in the two groups of patients,it was found that mFI-11High patients had higher rates of 1-year postoperative mortality,admission to ICU,anastomotic fistula,and 6-mo mortality than the mFI-11Low group(18.0%vs 8.9%,P=0.001;31.7%vs 14.7%,P<0.001;7.9%vs 2.8%,P<0.001;and 12.2%vs 3.6%,P<0.001).Multivariate analysis revealed mFI-11 as an independent predictive indicator for postoperative outcome[1-y

关键词： Gastric cancer Frailty Mortality Anastomotic fistula Elderly

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More Cycles of Intravenous Chemotherapy are Associated with Reduced Growth in Children with Retinoblastoma

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Journal of Nutritional Oncology 2021年第3期6卷 126-133页

作者： yu Qiong Yang Liang yu Yin xin Lin Bing hao Xiao yue Guan Hong Xia Xu Hong Feng yuan Department of Ophthalmology Daping HospitalArmy Medical University(Third Military Medical University)Chongqing 400042China Department of Clinical Nutrition Daping HospitalArmy Medical University(Third Military Medical University)Chongqing 400042China Institute of Hepatopancreatobiliary Surgery Southwest HospitalArmy Medical University(Third Military Medical University)Chongqing 400038China

Background Chemotherapy can have a negative impact on the growth of children with different cancers.However,few studies have examined whether intravenous chemotherapy(IVC)affects the growth of children with retinoblastoma(RB).The present study evaluated the height differences(actual height compared to the age standardized value)and survival of pediatric RB patients treated with IVC.Methods This was an observational cohort study.A total of 87 pediatric RB patients were included.The study population was stratified into two groups based on the number of chemotherapy cycles administered(≤4 versus>4).The height at baseline(before IVC),height after IVC and overall survival were compared between the two groups.Results Before IVC,no height differences were observed between the two groups(P=0.585).After IVC,all of the patients had a reduced height compared to the age standardized height(P=0.035).Patients who underwent more cycles of chemotherapy had a greater height difference compared to those who received fewer cycles(P=0.008).For those who had reduced height,the difference was positively associated with the number of chemotherapy cycles(r=0.279,P=0.043).Among the patients who exhibited a greater height difference,those who underwent more than four cycles of chemotherapy had a decreased overall survival(P=0.042).Conclusions Pediatric RB patients who underwent more cycles of chemotherapy were more likely to have a reduced height.Further studies are needed to determine the optimal treatment strategy to prevent the reduced growth while maintaining the benefits of chemotherapy.

关键词： Retinoblastoma Intravenous chemotherapy Height Survival

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Numerical Study on Lateral Buckling Mode of Pipelines Laid on A Sleeper

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China Ocean Engineering 2023年第3期37卷 495-505页

作者： LIU Run hao xin-tong LI Cheng-feng yu Zheng LI Qing-xin State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Because non-buried submarine pipelines under cyclic thermal loading are prone to global buckling,sleepers are commonly laid along the pipeline route to induce a series of relatively small and controllable lateral buckling.A finite element model which can simulate the transformation of pipeline laid on a sleeper from vertical buckling to lateral buckling is established in this work.The parameters of sleeper affecting pipeline buckling modes are analysed,and a new kind of sleeper is proposed aimed at avoiding antisymmetric buckling.Results show that the lateral trigger force can avoid antisymmetric lateral buckling when acting between 1℃and 13℃before the critical buckling temperature.The range increases slightly with increasing trigger force.Compared with an ordinary sleeper,the proposed new sleeper with slider can reduce the critical buckling temperature by 25%,which significantly improves the success rate of sleepers.

关键词： submarine pipeline buckling mode initial imperfection new sleeper

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Investigation on strong nonlinear interactions between underwater explosion and water surface based on compressible multiphase flow with phase transition

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Journal of Hydrodynamics 2023年第2期35卷 351-364页

作者： Jun yu Hai-kun Wang Zhen-xin Sheng Yi hao China Ship Scientific Research Center Wuxi214082China Taihu Laboratory of Deep-sea Technological Science Wuxi214082China

The strong nonlinear interactions between underwater explosion and water surface were numerically investigated using a phase transition model based on a four-equation system,which can deal with the complex deformable interface among different phases,including water,air,explosion bubble,and cavitation.The numerical method is verified by comparing the numerical results with experimental results,and good agreements are found.This study considers an ideal sine wave for simulating the shape of water surface.Two examples of different detonation depths of charge are investigated.In each example,the first case is the basic simulation without surface wave,and the other three cases are the simulations with sine waves of different wavelengths.Unique characteristics of the interactions,such as shock wave propagation,explosion bubble expansion,and the generation,development,and collapse of cavitation,are observed in the numerical simulations.By capturing the detailed density and pressure contours during the interaction process,we can better understand the underlying mechanisms of the explosion bubble,cavitation,and surface waves.These numerical results demonstrate that geometric nonlinearity impacts cavitation evolution and the explosion bubble movement mechanism.Additionally,the secondary cavitation phenomenon has been found in the cases without surface wave,and its fundamental physical mechanism is presented in detail.The present results can expand the existing database of multiphase flow in the underwater explosion and provide an insight into the strong nonlinear interaction between the underwater explosion and water surface.

关键词： Underwater explosion compressible multiphase flow phase transition model cavitation water surface

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Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第8期23卷 610-620页

作者： yu-hao WU Yan-hao FENG Li-wu FAN Qing WANG xin SONG Zi-tao yu Institute of Thermal Science and Power Systems Zhejiang UniversityHangzhou 310027China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China Institute of Soil Science Chinese Academy of SciencesNanjing 210008China

Soil backfilling and compaction are often involved in urban construction projects like the burying of power cables.The thermal conductance of backfill soil is therefore of great interest.To investigate the thermal conductivity variation of compacted backfill soil,10 typical soils sampled in Zhejiang Province of China with moisture contents of 0%–25%were fully compacted according to the Proctor compaction test method and then subjected to thermal conductivity measurement using the thermal probe method at 20℃.The particle size distribution and the chemical composition of the soil samples were characterized to analyze their effects on thermal conductivity.The results showed that the maximum thermal conductivity of fully compacted soils generally exceeds 1.9 W/(m·K)and is 20%–50%higher than that of uncompacted soils.With increasing moisture content,soil thermal conductivity and dry bulk density first increase and then remain unchanged or decrease slowly;the critical moisture content is greater than 20%in most cases.Overall,the critical moisture content of soils with large particle size is lower than that of those with small particle size.Quartz has the highest thermal conductivity in the soil solid phase,and the mass percentage of quartz for most soils in this study is more than 50%,while that for yellow soil is less than 30%,which leads to the thermal conductivity of the former being nearly twice as great as that of the latter in most circumstances.Based on regression analysis,with moisture content and dry bulk density as the independent parameters,the prediction formulae for the thermal conductivity of two categories of compacted backfill soils are proposed for practical applications.

关键词： Backfill soil Compaction Thermal conductivity Moisture content Dry bulk density

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Hydrodynamic Response of A Fully Coupled TLP Hull-TTR System with Detailed Modeling of A Hydraulic Pneumatic Tensioner and Riser Joints

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China Ocean Engineering 2022年第3期36卷 451-463页

作者： hao Shuai yu Yang yu Jian-xing yuAN Zhi-ming XU Li-xin Maritime College Tianjin University of TechnologyTianjin 300384China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Port and Ocean Engineering Tianjin UniversityTianjin 300072China Department of Naval Architecture Ocean&Marine EngineeringUniversity of StrathclydeGlasgow G40LZUK

Tension Leg Platform(TLP)in deepwater oil and gas field development usually consists of a hull,tendons,and top tension risers(TTRs).To maintain its top tension,each TTR is connected with a tensioner system to the hull.Owing to the complicated configuration of the tensioners,the hull and TTRs form a strong coupled system.Traditionally,some simplified tensioner models are applied to analyze the TLP structures.There is a large discrepancy between their analysis results and the actual mechanism behaviors of a tensioner.It is very necessary to develop a more detailed tensioner model to consider the coupling effects between TLP and TTRs.In the present study,a fully coupled TLP hull-TTR system for hydrodynamic numerical simulation is established.A specific hydraulic pneumatic tensioner is modeled by considering 4 cylinders.The production TTR model is stacked up by specific riser joints.The simulation is also extended to analyze an array of TTRs.Different regular and irregular waves are considered.The behaviors of different cylinders are presented.The results show that it is important to consider the specific configurations of the tensioner and TTRs,which may lead to obviously different response behaviors,compared with those from a simplified model.

关键词： top tension riser(TTR) fully coupled hull-tendon-TTR-tensioner model hydraulic pneumatic tensioner hydrodynamic response 3D potential flow theory

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The momentum distributions of triatomic molecular ion H_(3)^(2+) by intense laser pulses

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Communications in Theoretical Physics 2023年第6期75卷 112-119页

作者： Zhi-Xian Lei Shu-Juan Yan Xin-Yu Hao Pan Ma Sheng-Peng Zhou Jing Guo Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

We investigate theoretically the photoionization of triatomic molecular ion H_(3)^(2+) by numerically solving the two-dimensional time-dependent Schrödinger equations under Bohn-Oppenheimer approximation.The results show that the photoelectron momentum distributions(PMDs)of H_(3)^(2+) with different initial states are strongly dependent on the laser ellipticities and molecular orbital symmetry,and the PMDs of degenerate electronic states E^(±)are mirror images.Also,for degenerate electronic states E^(±),vortex structures appear in the PMDs by the counter-rotating circularly polarized laser pulses as the time delay between the two pulses increases,which can be explained by multicenter ionization and ultrafast photoionization model.

关键词： momentum distribution ringlike molecules intense laser fields

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Multifunctional Waterborne Polyurethane Nanocomposite Films with Remarkable Electromagnetic Interference Shielding,Electrothermal and Solarthermal Performances

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Chinese Journal of Polymer Science 2023年第2期41卷 267-277页

作者： Ming-Ke Xu xin-Jie Luo hao-Bin Zhang yu Zhang Lulu Li xin-Feng Zhou Zhong-Zhen yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing100029China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029China

To impart polymers with high electrical conductivity and satisfactory electromagnetic interference shielding efficiency,it is crucial to efficiently construct interconnecting networks of conductive nanofillers in polymer matrices.Herein,on the basis of the three-dimensional(3D)skeleton and volume-exclusion effect of silane-modified tetra-needle ZnO(ST-ZnO)whiskers and the high conductivity of two-dimensional MXene nanosheets,multifunctional MXene/ST-ZnO/waterborne polyurethane(MTW)nanocomposite films are fabricated by coating of MXene on ST-ZnO followed by compounding with waterborne polyurethane.The 3D four-needles of the whiskers facilitate the formation of an interconnecting network in the waterborne polyurethane matrix,while the coating of MXene efficiently makes the interconnecting network of the whiskers conductive at a low amount of the MXene.The resultant MTW ternary nanocomposite film exhibits not only a high electrical conductivity of 4.8×10^(4)S/m,but also an excellent electromagnetic interference shielding effectiveness of over 70 dB in the X-band at a low thickness of 100µm.In addition,the ternary film also exhibits outstanding Joule heating performances with an equilibrium temperature of 113℃at a low driving voltage of 3 V.The multifunctional nanocomposite films are promising for applications in portable and wearable electronics and flexible electromagnetic interference shielding devices.

关键词： Electrical conductivity Electromagnetic interference shielding Nanocomposite films Waterborne polyurethane MXene nanosheets

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Fluorine Substitution Effect on the Material Properties in Transparent Aromatic Polyimides

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Chinese Journal of Polymer Science 2022年第7期40卷 781-788页

作者： Wei-Feng Peng Huan-yu Lei xin-xin Zhang Lu-hao Qiu Ming-Jun Huang South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou510640China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

The recent development of flexible display technology raised additional requirements for optical and electric properties of polyimides,accelerating the structure and property tunning of transparent polyimides.The unique electronic effect and steric hindrance effect of fluorine substitutions make fluorine-containing polyimides occupy an important position in the transparent polyimide family.In this work,a series of transparent aromatic polyimides were prepared from a fixed 4,4’-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)and biphenyl diamines with different substitute groups at the 2,2’,6,6’-positions.We systematically studied the effects of pendant groups on the thermal,mechanical,optical and dielectric properties of these 6FDA-based polyimides with the aid of density function theory(DFT)calculation.In particular,we paid special attention to the simple but compact fluoro group substitution.The simple fluoro substitution brought the advantages of maintaining the linearity of the backbone and dense polymer chain packing,which would minimize the weakening of polyimides’inherent thermal,dimensional and mechanical properties.Comparing with trifluoromethyl substituted polyimides with the best optical transparency,polyimides containing fluoro substitutes exhibited slightly decreased optical transparency,but increased thermal and dimensional stability and higher mechanical strength.These results could shed light on the ultimate transparent polyimide film development toward the application in extreme working condition,e.g.,the colorless polyimide substrate film for the flexible display technology.

关键词： Polyimides Fluorine substitution Transparent Dielectric Colorless

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Constructing central hollow cylindrical reduced graphene oxide foams with vertically and radially orientated porous channels for highly efficient solar-driven water evaporation and purification

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Nano Research 2023年第5期16卷 6343-6352页

作者： Changjun Li Wei Li hao-yu Zhao xin-yue Feng Xiaofeng Li Zhong-Zhen yu State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Although solar steam generation is an eco-friendly approach for desalinating seawater and purifying wastewater,there are still issues on how to improve the efficiency of solar energy utilization and accelerate the water and heat transport inside the solardriven water evaporators.Herein,we design a central hollow cylindrical reduced graphene oxide(RGO)foam with vertically and radially orientated channels as a solar steam generation device for efficient water evaporation and purification.The vertically aligned porous channels accelerate upward transport of water to the top evaporation surface,while the radially aligned porous channels facilitate water transport and heat transfer along the radial directions for fully utilizing the heat accumulated inside the central cylindrical hole of the foam.The central hole of the foam plays a highly positive role in accumulating more heat for accelerating the water evaporation,the newly generated inner sidewall resulted from the central hole can gain extra thermal energy from surrounding environment in the same way as the outer sidewall of the foam due to the surface cooling effect of the water evaporation.As a result,the vertically and radially aligned RGO foam evaporator with central hollow cylinder achieves a high solar steam generation rate of 2.32 kg·m^(−2)·h^(−1)with an exceptional energy conversion efficiency of 120.9%under 1-sun irradiation,superior to the vertically aligned RGO foam without the central hole(1.83 kg·m^(−2)·h^(−1),96.9%)because of the enhanced water and heat transfer inside the porous channels,the efficient utilization of environmental energy.

关键词： hollow cylindrical foams reduced graphene oxide solar steam generation water evaporation rate seawater desalination

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