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Optimization of Extraction Process and Antioxidant Activity of Polysaccharide in Embelia parviflora Wall.by RSM 被引量:2
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作者 Wenli LI Xianxian LIU +6 位作者 Xiaolian LIANG Yong CHEN Danqing PANG Zhouyan HUANG Qian HAN Wenjun LIU Liangni CHEN 《Medicinal Plant》 CAS 2020年第3期34-38,42,共6页
[Objectives]To optimize the extraction process of polysaccharide in Embelia parviflora Wall.by response surface methodology,and to study the antioxidant activity in vitro of polysaccharide in E.parviflora,so as to pro... [Objectives]To optimize the extraction process of polysaccharide in Embelia parviflora Wall.by response surface methodology,and to study the antioxidant activity in vitro of polysaccharide in E.parviflora,so as to provide a basis for the further development and utilization of E.parviflora.[Methods]The solid-to-liquid ratio,extraction temperature,extraction time and extraction times were used as single factors to investigate the effects.On this basis,the response surface methodology(RSM)was used to optimize the extraction process of polysaccharide in E.parviflora.DPPH and ABTS free radicals were used to investigate the antioxidant capacity of polysaccharide in E.parviflora.[Results]The optimal solid-to-liquid ratio for extraction of polysaccharide from E.parviflora was 32∶1(mL/g),extraction temperature was 77℃,and extraction time was 36 min.The IC50 values of DPPH and ABTS were 0.04 and 0.03 mg/mL,respectively.[Conclusions]The optimized extraction process of polysaccharide in E.parviflora is stable,the extraction rate is high,and has strong antioxidant activity.It is expected to provide a reference for the industrial extraction of polysaccharide from E.parviflora. 展开更多
关键词 Embelia parviflora wall. POLYSACCHARIDE Response surface methodology(RSM) Antioxidant activity
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On the HPLC Fingerprint of Zhuang Medicine Spilanthes paniculata Wall. ex DC.
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作者 Li LI Fengfeng XIE +2 位作者 Pinghua YAN Xiangyan ZENG Yi CAI 《Medicinal Plant》 CAS 2019年第3期19-23,共5页
[Objectives] To establish the HPLC fingerprint of Spilanthes paniculata Wall. ex DC. and provide reference for the quality control of medicinal materials. [Methods]Welch Ultimate XB-C18( 5 μm,250 mm ×4. 6 mm) ch... [Objectives] To establish the HPLC fingerprint of Spilanthes paniculata Wall. ex DC. and provide reference for the quality control of medicinal materials. [Methods]Welch Ultimate XB-C18( 5 μm,250 mm ×4. 6 mm) chromatographic column was adopted,and the mobile phase was acetonitrile-0. 1% phosphoric acid aqueous solution for gradient elution,the detection wavelength was 328 nm,the column temperature was 25 ℃,the similarities of 18 different batches of medicinal materials were evaluated,and the HPLC fingerprint chromatogram of S. paniculata Wall. ex DC. was set up. [Results] The RSDs of precision,repeatability and stability of HPLC fingerprint of 18 batches of S. paniculata Wall. ex DC. medicine materials were all less than 3%;HPLC reference fingerprint of the medicine materials was established.[Conclusions]HPLC fingerprint was established,its data were stable and reliable,and the method was simple and efficient,which could provide reference for the quality evaluation of Zhuang medicine S. paniculata Wall. ex DC. 展开更多
关键词 Zhuang MEDICINE Spilanthes paniculata wall. EX DC. HPLC FINGERPRINT
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Extraction Process and Antioxidant Activity of Polysaccharides from Cyathula Capitata( Wall. ) Moq.
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作者 Jingxia WANG Keyong ZHU +1 位作者 Yuanhong SHANG Yuan LIU 《Medicinal Plant》 CAS 2018年第5期31-35,共5页
[Objectives]To optimize the ultrasonic-assisted extraction process of polysaccharides from Cyathula Capitata( Wall.) Moq. and evaluate its antioxidant capacity in vitro. [Methods] The single factor orthogonal design w... [Objectives]To optimize the ultrasonic-assisted extraction process of polysaccharides from Cyathula Capitata( Wall.) Moq. and evaluate its antioxidant capacity in vitro. [Methods] The single factor orthogonal design was applied to explore the effects of ultrasonic time,solid-to-liquid ratio,extraction time and ethanol precipitation concentration on the extraction rate of crude polysaccharides from C. Capitata,to obtain the optimal extraction process; DPPH and ABTS^+ free radical scavenging ability was detected to evaluate its in vitro antioxidant activity.[Results]The optimal extraction process of C. Capitata crude polysaccharide was as follows: solid-to-liquid ratio was 40∶ 1,the extraction temperature was 50℃,the ultrasonic time was 80 min. Under such conditions,the extraction rate of C. Capitata crude polysaccharide was 10. 51%,and the purity was 56. 9%; C. Capitata crude polysaccharide has good scavenging ability to DPPH and ABTS^+ free radicals,and its IC_(50) values are 0. 468 and 0. 231 mg/mL,respectively. [Conclusions]The optimized process is simple and feasible,and the C. Capitata polysaccharide has good antioxidant activity in vitro. This experiment provides a basis for the further development and utilization of the C. Capitata polysaccharide. 展开更多
关键词 Cyathula Capitata (wall.) Moq. POLYSACCHARIDE EXTRACTION process ANTIOXIDANT activity
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Jadwar(Delphinium denudatum Wall.):a medicinal plant
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作者 Roghayeh Baghervand Navid Mehrdad Karimi +5 位作者 Morteza Ghojazadeh Seyed Mostafa Araj-Khodaei Alireza Bagherzadeh karimi Sanam Dolati Mehri Bansans Seyed Mohammad Bagher Fazljou 《Traditional Medicine Research》 2020年第6期487-497,共11页
Delphinium denudatum Wall.is one of the important medicinal herbs of traditional Persian medicine and is known as Jadwar.Medicinal plants are the most widely used drugs in traditional Persian medicine and has been use... Delphinium denudatum Wall.is one of the important medicinal herbs of traditional Persian medicine and is known as Jadwar.Medicinal plants are the most widely used drugs in traditional Persian medicine and has been used for various diseases since earlier times.The medicinal uses of Delphinium denudatum Wall.date back to over 1,000 years ago.Rhazes(845–925 C.E.)was the first Persian physician and scientist who reported the use of Delphinium denudatum Wall.as a herbal remedy.During the following centuries,the usages of Delphinium denudatum Wall.in the treatment of various diseases has been mentioned in the books and references of traditional Persian medicine for cures to various diseases such as neurologic and psychiatric disease,gastrointestinal disease,fever,pain,and poisoning.According to modern studies,the dried roots of Delphinium denudatum Wall.have antipyretic,antimicrobial,anticonvulsant,hepatoprotective,antioxidant,and pain-relieving properties.Biomolecules from roots of Delphinium denudatum Wall.were also identified as potential cures for central nervous system diseases as well as for the amelioration of morphine addiction.Delphinium denudatum Wall.,with its properties involving the prevention of mitochondrial dysfunction,reduction of oxidative stress,and inflammation and immune dysregulation,can be utilized in curing inflammatory disorders.The effective therapeutic influence of root extract of Delphinium denudatum Wall.against several diseases needs to be confirmed through controlled clinical trials.This article reviews the different features of Delphinium denudatum Wall.and focuses on the well-known therapeutic effects of this herbal drug on various human disorders and animal disease models. 展开更多
关键词 Delphinium denudatum wall. Jadwar root Traditional Persian medicine Neurologic and psychiatric effects Anticonvulsant effects
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Chemical Composition of Fruit of Embelia undulata(Wall.)Mez
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作者 Ling CHAI Jiantong YUAN +1 位作者 Mingsheng CHEN Buming LIU 《Medicinal Plant》 CAS 2021年第3期24-26,共3页
[Objectives]To study the chemical constituents of the fruit of Embelia undulata(Wall.)Mez.[Methods]Silica gel column chromatography,gel column chromatography,recrystallization,high-performance preparative liquid chrom... [Objectives]To study the chemical constituents of the fruit of Embelia undulata(Wall.)Mez.[Methods]Silica gel column chromatography,gel column chromatography,recrystallization,high-performance preparative liquid chromatography and other modern separation methods and techniques were used to separate and purify the chemical components of the ethyl acetate fraction of the fruit of E.undulata(Wall.)Mez,and based on the physical and chemical properties and spectral data,their structure was identified.[Results]Six compounds were isolated from the fruit of E.undulata(Wall.)Mez,including trimethyl citrate(1),vanillic acid(2),5-hydroxymethylfurfural(3),1,5-dimethyl citrate(4),1,6-dimethyl-5-ethyl citrate(5)and 3,4-dihydroxybenzoic acid(6).[Conclusions]Compounds 1-6 are all isolated from E.undulata(Wall.)Mez for the first time. 展开更多
关键词 Embelia undulata(wall.)Mez FRUIT Ethyl acetate fraction Chemical constituent
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Macropropagation and Production of Clonal Planting Materials of Panax pseudoginseng Wall.
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作者 Sakutemsu Lolen Jamir Chitta Ranjan Deb Nangshimeren Sakutemsu Jamir 《Open Journal of Forestry》 2016年第2期135-141,共7页
Panax pseudoginseng Wall., a highly medicinal, herbaceous, long-lived plant, grows in the forest litter of shady primary forest. The species is threatened in the natural habitat due to unsustainable harvesting of rhiz... Panax pseudoginseng Wall., a highly medicinal, herbaceous, long-lived plant, grows in the forest litter of shady primary forest. The species is threatened in the natural habitat due to unsustainable harvesting of rhizome for medicine and habitat destruction. The species has very poor adaptive power to the synthetic environment and fails to grow and propagate. Present study was undertaken to develop suitable low cost propagation technique and produce clonal planting materials through rhizome splitting and root cutting. Rhizomes and roots were cut into segments and sowed in the raised soil bed prepared by mixing decayed wood powder, sand and top black soil at 1:1:3 ratios in a shaded poly house. Of the sowed rhizome segments ~55% segments remained recalcitrant to morphogenetic response in the first year of the study and the response improved in the subsequent years. In the third year ~51% rhizome segments responded positively. The horizontal root cuts mostly remained morphogenetically dormant but inclined root cuts exhibited better response. The morphogenetic response from the roots was comparatively very poor compare to rhizome segments. The plantlets formed both rhizome segments and root cuttings were maintained for three years in the bed/pots followed by transferring in the cultivated plots. 展开更多
关键词 Panax pseudoginseng wall. Macropropagation Medicinal Plant Rhizomes Splitting Root Propagation
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Biological Characteristics of Alternaria tenuissima on Dendrobium sandidium Wall.et Lindl.
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作者 Yue Haimei Gong Wenfeng Wang Mu 《Plant Diseases and Pests》 CAS 2014年第6期22-24,共3页
Biological characteristics of Alternaria tenuissima on Dendrobium sandidium Wall. et Lindl. were studied. The result showed that A. tenuissima on D.sandidium Wall. et Lindl. could grow at temperature 5- 35 ℃ and p H ... Biological characteristics of Alternaria tenuissima on Dendrobium sandidium Wall. et Lindl. were studied. The result showed that A. tenuissima on D.sandidium Wall. et Lindl. could grow at temperature 5- 35 ℃ and p H value of 2- 10,the optimal temperature and p H value were 25℃ and 7 for its growth and sporulation,respectively. Starch was the optimal carbon sources and peptone was the optimal nitrogen source for the growth and sporulation of bacterial colony,respectively; PSA and PCA were the optimal media for its growth and sporulation,respectively. 展开更多
关键词 生物学特性 链格孢 石斛 最适温度 孢子形成 细菌菌落 媒体公司 PH值
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Experimental and numerical study on protective effect of RC blast wall against air shock wave
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作者 Xin-zhe Nian Quan-min Xie +2 位作者 Xin-li Kong Ying-kang Yao Kui Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期567-579,共13页
Prototype experiments were carried out on the explosion-proof performance of the RC blast wall.The mass of TNT detonated in the experiments is 5 kg and 20 kg respectively.The shock wave overpressure was tested in diff... Prototype experiments were carried out on the explosion-proof performance of the RC blast wall.The mass of TNT detonated in the experiments is 5 kg and 20 kg respectively.The shock wave overpressure was tested in different regions.The above experiments were numerically simulated,and the simulated shock wave overpressure waveforms were compared with that tested and given by CONWEP program.The results show that the numerically simulated waveform is slightly different from the test waveform,but similar to CONWEP waveform.Through dimensional analysis and numerical simulation under different working conditions,the equation for the attenuation rate of the diffraction overpressure behind the blast wall was obtained.According to the corresponding standards,the degree of casualties and the damage degree of the brick concrete building at a certain distance behind the wall can be determined when parameters are set.The above results can provide a reference for the design and construction of the reinforced concrete blast wall. 展开更多
关键词 Blast wall Shock wave DIFFRACTION OVERPRESSURE Protection
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Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading
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作者 Su Xing Yan Shi +1 位作者 Sun Xianglei Wang Tao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期65-85,共21页
Frame and rocking wall(FRW)structures have excellent resilient performance during earthquakes.However,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during ... Frame and rocking wall(FRW)structures have excellent resilient performance during earthquakes.However,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking process.An innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed tendons.Moreover,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral resistance.Two SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the SCRW.The key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were explored.The results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the SCRW.The restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic SW.In addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of concrete.The rocking range of the rocking center is about 41.4%of the width of the SCRW. 展开更多
关键词 self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center
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Experimental and numerical study regarding H-steel all-bolted connection steel frame with composite wall boards
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作者 Fan Min Guo Hongchao +2 位作者 Li Shen Wang Zhenshan Wang Huaqiang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期427-443,共17页
H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied.The failure modes,... H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied.The failure modes,hysteresis curves,bearing capacity,ductility,energy dissipation capacity,stiffness degradation and strain distribution were discussed.The calculation method of structural theoretical internal force was presented.The results showed that the overall structural seismic performance was better,and the structural ductility met the demands of elastic-plastic inter-story drift angle for seismic design.The H-steel weak-axis connection structure obtained better energy dissipation capacity,and its bearing capacity and stiffness were slightly different from the strong-axis connection.The heat preservation and decoration performance of composite wallboard and the all-bolted connection of the steel frame realized prefabrication during the whole construction period.The plastic hinge of the steel beam can be moved outwards because of the L-angles,which effectively avoids stress concentration in joint areas and expands the plastic hinge range.The errors between the theoretical structural capacity calculated by the plastic analysis method and the test results were within 2.44%.In addition,structural failure mechanisms and bearing capacities were verified by the finite element(FE)analysis,and the effects of the main parameters on the structures were investigated.The FE verification results were the same as in the test.The research results provide theoretical support and technical guidance for the application of thermal insulation and decorative composite wall panels in H-shaped steel all-bolted steel frames. 展开更多
关键词 composite wall boards all-bolted steel frame H-steel low-cyclic loading failure modes
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Effect of Bogie Cavity End Wall Inclination on Flow Field and Aerodynamic Noise in the Bogie Region of High-Speed Trains
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作者 Jiawei Shi Jiye Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2175-2195,共21页
Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically s... Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically studied.First,the simulation is conducted based on a simplified cavity-bogie model,including five cases with different inclination angles of the front and rear walls of the cavity.By comparing and analyzing the flow field and acoustic results of the five cases,the influence of the regularity and mechanism of the bogie cavity end wall inclination on the flow field and the aerodynamic noise of the bogie region are revealed.Then,the noise reduction strategy determined by the results of the simplified cavity-bogie model is applied to a three-car marshaling train model to verify its effectiveness when applied to the real train.The results reveal that the forward inclination of the cavity front wall enlarges the influence area of shear vortex structures formed at the leading edge of the cavity and intensifies the interaction between the vortex structures and the front wheelset,frontmotor,and front gearbox,resulting in the increase of the aerodynamic noise generated by the bogie itself.The backward inclination of the cavity rear wall is conducive to guiding the vortex structures flow out of the cavity and weakening the interaction between the shear vortex structures and the cavity rear wall,leading to the reduction of the aerodynamic noise generated by the bogie cavity.Inclining the rear end wall of the foremost bogie cavity of the head car is a feasible aerodynamic noise reduction measure for high-speed trains. 展开更多
关键词 BOGIE cavity flow aerodynamic noise end wall inclination
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen NUTRIENTS wall disruption Phenolic compounds In vitro digestion
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Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing
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作者 Luqiang Ding Chengzhi Xiao Feilong Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期711-725,共15页
To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general... To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and b.The conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr relationships.The test results show that increasing Pr accelerates the development of creep deformation for both geogrids.Meanwhile,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other studies.Based on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous literature.Performance evaluation and comparison of the proposed model with six available prediction models were performed.Then a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years afterwards.The findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall height.Finally,the limitations and application prospects of the proposed model were discussed and analyzed. 展开更多
关键词 GEOSYNTHETICS Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model
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Influence of Various Earth-Retaining Walls on the Dynamic Response Comparison Based on 3D Modeling
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作者 Muhammad Akbar Huali Pan +2 位作者 Jiangcheng Huang Bilal Ahmed Guoqiang Ou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2835-2863,共29页
The present work aims to assess earthquake-induced earth-retaining(ER)wall displacement.This study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement co... The present work aims to assess earthquake-induced earth-retaining(ER)wall displacement.This study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining walls.The finite element(FE)simulations utilized a 3D plane strain condition to model full-scale ER walls and numerous nonlinear dynamics analyses.The seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE approach.It also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic strain.Three components of the created ER walls were found throughout this research procedure.One is a granular reinforcement backfill,while the other is a wall-facing panel and base foundation.The dynamic response effects of varied earth-retaining walls have also been studied.It was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER walls.The proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE simulation.The results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two types.The methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers. 展开更多
关键词 Seismic analysis finite element modeling earth-retaining ER walls dynamic response structural resilience
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An impact sensitivity assessment method of spacecraft based on virtual exterior wall
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作者 Runqiang Chi Yuyan Liu +1 位作者 Diqi Hu Baojun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期142-157,共16页
The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft... The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft. 展开更多
关键词 Sensitivity OD/M SPACECRAFT Virtual exterior wall
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Protective effect of retaining wall on rock avalanche:A case study of Nayong rock avalanche in China
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作者 WANG Zhongfu SHI Fengge +3 位作者 HE Siming ZHANG Xusheng WANG Jingying LIU Enlong 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1215-1230,共16页
Rock avalanches are generally difficult to prevent and control due to their high velocities and the extensive destruction they cause.However,barrier structures constructed along the path of a rock avalanche can partia... Rock avalanches are generally difficult to prevent and control due to their high velocities and the extensive destruction they cause.However,barrier structures constructed along the path of a rock avalanche can partially mitigate the magnitudes and consequences of such catastrophic events.We selected a rock avalanche in Nayong County,Guizhou Province,China as a case to study the effect of the location and height of a retaining wall on the dynamic characteristics of rock avalanche by using both actual terrain-based laboratory-model tests and coupled PFC3D-FLAC3D numerical simulations.Our findings demonstrate that a retaining wall can largely block a rock avalanche and its protective efficacy is significantly influenced by the integrity of the retaining wall.Coupled numerical simulation can serve as a powerful tool for analyzing the interaction between a rock avalanche and a retaining wall,facilitating precise observations of its deformation and destruction.The impact-curve characteristics of the retaining wall depend upon whether or not the rock avalanche-induced destruction is taken into account.The location of the retaining wall exerts a greater influence on the outcome compared to the height and materials of the retaining wall,while implementing a stepped retaining-wall pattern in accordance with the terrain demonstrates optimal efficacy in controlling rock avalanche. 展开更多
关键词 Rock avalanche Laboratory model test Retaining wall PFC^(3D) FLAC^(3D) Impact force
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Malignant triton tumor in the abdominal wall:A case report
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作者 Ho Jik Yang Donghyun Kim +1 位作者 Won Suk Lee Sang-Ha Oh 《World Journal of Clinical Cases》 SCIE 2024年第8期1467-1473,共7页
BACKGROUND Malignant triton tumors(MTTs)comprise a subgroup of malignant peripheral nerve sheath tumors(MPNSTs)that exhibits rhabdomyosarcomatous differen-tiation and follow an aggressive course.MTTs are primarily loc... BACKGROUND Malignant triton tumors(MTTs)comprise a subgroup of malignant peripheral nerve sheath tumors(MPNSTs)that exhibits rhabdomyosarcomatous differen-tiation and follow an aggressive course.MTTs are primarily located along peripheral nerves.Cases of MTTs in the abdominal wall have not been reported.MTT has a poorer prognosis than classic MPNSTs,and accurate diagnosis necessitates a keen understanding of the clinical history and knowledge of its differential diagnosis intricacies.Treatment for MTTs mirrors that for MPNSTs and is predominantly surgical.CASE SUMMARY A 49-year-old woman presented with a subcutaneous mass in her lower abdo-minal wall and a pre-existing surgical scar that had grown slowly over 3-4 months before the consultation.She had previously undergone radical hysterectomy and concurrent chemo-radiotherapy for cervical cancer approximately 5 years prior to the consultation.Abdominal computed tomography(CT)showed a 1.3 cm midline mass in the lower abdomen with infiltration into the rectus abdominis muscle.There was no sign of metastasis(T1N0M0).An incisional biopsy identified sporadic MTT of the lower abdomen.A comprehensive surgical excision with a 3 cm margin inclusive of the peritoneum was executed.Subse-quently,the general surgeon utilized an approach akin to the open peritoneal onlay mesh technique.The patient underwent additional treatment with an excision shaped as a mini-abdominoplasty for the skin defect.No complications arose,and annual follow-up CTs did not show signs of recurrence or metastasis.CONCLUSION An abdominal MTT was efficaciously treated with extensive excision and abdominal wall reconstruction,eliminating the need for postoperative radiotherapy. 展开更多
关键词 Malignant triton tumor Abdominal wall Surgical excision RECONSTRUCTION Case report
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Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging
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作者 Yong-Qian Mo Hai-Yu Luo +5 位作者 Han-Wen Zhang Yu-Feng Liu Kan Deng Xiao-Lei Liu Biao Huang Fan Lin 《World Journal of Diabetes》 SCIE 2024年第1期72-80,共9页
BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imag... BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intracranial arterial remodelling and diabetes is still unclear.In recent years,with the development of magnetic resonance technology and the emergence of high-resolution(HR)vascular wall imaging,a clear and multidimensional display of the intracranial vascular wall has been achieved.Therefore,in this study,HR wall imaging(HR-VWI)was used to display the remodelling characteristics of bilateral middle cerebral arteries and basilar arteries and to explore the factors of intracranial vascular remodelling and its relationship with diabetes. 展开更多
关键词 High-resolution vessel wall imaging Intracranial atherosclerosis Vascular remodelling Magnetic resonance imaging
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Endoscopic treatment of bleeding gastric ulcer causing gastric wall necrosis:A case report
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作者 Wei-Feng Li Ruo-Yu Gao +1 位作者 Jing-Wen Xu Xi-Qiu Yu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1203-1207,共5页
BACKGROUND Gastric wall necrosis is a rare complication of endoscopic treatment for bleeding gastric ulcer,which may exacerbate the patient’s condition once it occurs and may even require surgical intervention for tr... BACKGROUND Gastric wall necrosis is a rare complication of endoscopic treatment for bleeding gastric ulcer,which may exacerbate the patient’s condition once it occurs and may even require surgical intervention for treatment.CASE SUMMARY A 59-year-old man was admitted to our department with melena.Endoscopy revealed a giant ulcer in the gastric antrum with a visible vessel in its center,which was treated with sclerosants and tissue glue injection and resulted in necrosis of the gastric wall.CONCLUSION Injection of sclerosants and tissue glue may lead to gastric wall necrosis,which is a serious complication.Therefore,before administering this treatment to patients,we should consider other more effective methods of hemostasis to avoid gastric wall necrosis. 展开更多
关键词 Bleeding gastric ulcer Sclerotherapy Lauromacrogol Tissue adhesive Gastric wall necrosis Case report
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Coinfection with hepatic cystic and alveolar echinococcosis with abdominal wall abscess and sinus tract formation:A case report
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作者 Miao-Miao Wang Xiu-Qing An +3 位作者 Jin-Ping Chai Jin-Yu Yang Ji-De A Xiang-Ren A 《World Journal of Hepatology》 2024年第2期279-285,共7页
BACKGROUND Hepatic cystic and alveolar echinococcosis coinfections,particularly with concurrent abscesses and sinus tract formation,are extremely rare.This article presents a case of a patient diagnosed with this uniq... BACKGROUND Hepatic cystic and alveolar echinococcosis coinfections,particularly with concurrent abscesses and sinus tract formation,are extremely rare.This article presents a case of a patient diagnosed with this unique presentation,discussing the typical imaging manifestations of both echinococcosis types and detailing the diagnosis and surgical treatment experience thereof.CASE SUMMARY A 39-year-old Tibetan woman presented with concurrent hepatic cystic and alveolar echinococcosis,accompanied by abdominal wall abscesses and sinus tract formation.Initial conventional imaging examinations suggested only hepatic cystic echinococcosis,but intraoperative and postoperative pathological examination revealed the coinfection.Following radical resection of the lesions,the patient’s condition improved,and she was discharged soon thereafter.Subsequent outpatient follow-ups confirmed no recurrence of the hydatid lesion and normal surgical wound healing.Though mixed hepatic cystic and alveolar echinococcosis with abdominal wall abscesses and sinus tract formations are rare,the general treatment approach remains consistent with that of simpler infections of alveolar echinococcosis.CONCLUSION Lesions involving the abdominal wall and sinus tract formation,may require radical resection.Long-term prognosis includes albendazole and follow-up examinations. 展开更多
关键词 Cystic echinococcosis Alveolar echinococcosis Abdominal wall abscess Surgical treatment Sinus tract Case report
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