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Correlation between anxiety, depression, and social stress in young patients with thoracolumbar spine fractures
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作者 Bo Wang Da Shi +1 位作者 Yin-Di Sun Bo Dong 《World Journal of Psychiatry》 SCIE 2025年第1期83-92,共10页
BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily comb... BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily combined with serious injuries to peripheral nerves and soft tissues,which causes paralysis of the lower limbs if there is no timely rehabilitation treatment.Young patients with thoracolumbar fractures find it difficult to recover after the operation,and they are prone to depression,low self-esteem,and other negative emotions.AIM To investigate the association between anxiety,depression,and social stress in young patients with thoracolumbar spine fractures and the effect on rehabilitation outcomes.METHODS This study retrospectively analyzed 100 patients admitted to the orthopedic department of Honghui Hospital,Xi’an Jiaotong University who underwent thoracolumbar spine fracture surgery from January 2022 to June 2023.The general data of the patients were assessed with the Hamilton anxiety scale(HAMA),Hamilton depression scale(HAMD),life events scale,and social support rating scale(SSRS)to identify the correlation between anxiety,depression scores,and social stress and social support.The Japanese Orthopedic Association(JOA)was utilized to evaluate the rehabilitation outcomes of the patients and to analyze the effects of anxiety and depression scores on rehabilitation.RESULTS According to the scores of HAMD and HAMA in all patients,the prevalence of depression in patients was 39%(39/100),and the prevalence of anxiety was 49%(49/100).Patients were categorized into non-depression(n=61)and depression(n=39),non-anxiety(n=51),and anxiety(n=49)groups.Statistically significant differences in gender,occupation,Pittsburgh Sleep Quality Index(PSQI)score,and monthly family income were observed between the non-depression and depression groups(P<0.05).A significant difference in occupation and PSQI score was found between the non-anxiety and anxiety groups.Both depression(r=0.207,P=0.038)and anxiety scores(r=0.473,P<0.001)were significantly and positively correlated with negative life events.The difference in negative life event scores as well as SSRS total and item scores was statist-ically significant between patients in the non-depression and depression groups(P<0.05).The difference between the non-anxiety and anxiety groups was statistically significant(P<0.05)in the negative life event scores as well as the total SSRS scores.Additionally,JOA scores were significantly lower in both anxious and depressed patients.CONCLUSION Young patients with thoracolumbar fractures are prone to anxiety and depression.Patients’anxiety and depression are closely associated with social pressure,which reduces the life pressure of young patients with thoracolumbar fractures,enhances social support,and improves the psychology of anxiety and depression.,which affects patients’recovery. 展开更多
关键词 Patients with thoracolumbar fractures ANXIETY DEPRESSION Social pressure Social support
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Clinical Study of Tianji Robotic-Assisted Surgery for Upper Cervical Spine Fractures
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作者 Chengkua Huang Yuanjian Huang +6 位作者 Weikang Yang Qianhou Zhou Xianhai Zeng Junlei Tan Mei Zhang Guosheng Su Sheng Nong 《Natural Science》 2024年第9期150-161,共12页
Object: To compare the safety, clinical efficacy, and complication rate of “Tianji” robot-assisted surgery with traditional open surgery in the treatment of cervical vertebrae fracture. Methods: 60 patients with upp... Object: To compare the safety, clinical efficacy, and complication rate of “Tianji” robot-assisted surgery with traditional open surgery in the treatment of cervical vertebrae fracture. Methods: 60 patients with upper cervical vertebrae fracture admitted to Baise People’s Hospital between November 2018 and April 2024 were retrospectively analyzed. Among these patients, 29 underwent “Tianji” robot-assisted surgery (Robot group), and 31 underwent traditional C-arm fluoroscopy-assisted open surgery (Open group). Statistical analysis of the data was performed using SPSS 27.0 software to compare general data (gender, age, BMI), preoperative and postoperative visual analogue scale (VAS) scores, neck disability index (NDI), intraoperative blood loss, accuracy of screw placement on imaging, and the number of complications in both groups for comprehensive evaluation. A P value < 0.05 was deemed to have achieved statistical significance. Results: There was no significant difference in preoperative VAS scores between the two groups (Robot group: 8.34 ± 0.61;Open group: 8.26 ± 0.68, P = 0.317). There was also no significant difference in VAS scores at 1 week postoperatively (Robot group: 6.90 ± 0.31;Open group: 6.94 ± 0.36, P = 0.3237). Preoperative NDI scores showed no significant difference between the two groups (Robot group: 43.31 ± 2.67;Open group: 43.84 ± 2.67, P = 0.2227), and the difference in NDI scores at 1 week postoperatively was also not significant (Robot group: 35.69 ± 4.24;Open group: 37.35 ± 3.48, P = 0.0509). Intraoperative blood loss in the Robot group was significantly lower than in the Open group (246.21 ± 209 ml vs 380.65 ± 328.04 ml, P = 0.0308), with a statistically significant difference. The operation time was longer in the Robot group (3.75 ± 0.74 h) compared to the Open group (2.74 ± 0.86 h). In terms of screw placement accuracy, the Robot group had a higher accuracy rate for Class A screws compared to the Open group (102 screws vs 94 screws, P = 0.0487), and the accuracy rate for Class B screws was also higher in the Robot group (13 screws vs 29 screws, P = 0.0333), with both differences being statistically significant. There was no significant difference in the number of complications between the two groups (Robot group: 8 cases;Open group: 10 cases, P = 0.6931). Conclusion: Patients treated with “Tianji” robot-assisted surgery for upper cervical vertebrae fracture had lower intraoperative blood loss and higher screw placement accuracy compared to those undergoing traditional C-arm fluoroscopy-assisted open surgery, indicating that this robot-assisted surgery can effectively reduce intraoperative blood loss and improve screw placement accuracy. 展开更多
关键词 Tiangui Robot Assisted Surgery Upper Cervical spine fracture Clinical Study fracture Repair
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Regulation of Pore Structure and Hightemperature Fracture Behavior of CACbonded Alumina-Spinel Castables Based on Hydration Design
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作者 Wenjing LIU Ning LIAO Yawei LI 《China's Refractories》 CAS 2024年第3期22-29,共8页
The lamellar hydrates of CAC were designed with the introduction of nano CaCO_(3)or Mg-Al hydrotalcite(M-A-H),and the effects on the green strength,pore structures,and high-temperature fracture behavior of alumina-spi... The lamellar hydrates of CAC were designed with the introduction of nano CaCO_(3)or Mg-Al hydrotalcite(M-A-H),and the effects on the green strength,pore structures,and high-temperature fracture behavior of alumina-spinel castables were investigated.The results show that nano CaCO_(3)or M-A-H stimulates rapidly the hydration of CAC and the formation of lamellar C_(4)AcH_(11)or coexistence of C_(2)AH_(8)and C_(4)AcH_(11)at 25℃.The formation of lamellar hydrates can contribute to a more complicated pore structure,especially in the range of 400-2000 nm.Meanwhile,the incorporation of well-distributed CaO or MgO sources from nano CaCO_(3)or M-A-H also regulates the distribution of CA_(6)and spinel(pre-formed and in-situ).Consequently,the optimized microstructure and complicated pore structure can induce the deflection and bridging of cracks,thus facilitating the consumption of fracture energy and enhancing the resistance to thermal stress damage. 展开更多
关键词 alumina-spinel castables lamellar hydrates pore structure high-temperature wedge splitting test fracture behavior
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Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report
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作者 Na Li Yue-Yue Ren +4 位作者 Ying Tang Qi Yang Tian-Tian Meng Song Li Jing Zhang 《World Journal of Clinical Cases》 SCIE 2025年第3期42-49,共8页
BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and te... BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in theliterature.CASE SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical level.After the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival overgrowth.Cone-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival overgrowth.CONCLUSION This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture. 展开更多
关键词 Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report
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Cauda equina syndrome with urinary retention as a postoperative complication of lumbar spine surgery:A case report
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作者 Kai-Wu Yang Wei-Hong Lai Da-Wei Huang 《World Journal of Clinical Cases》 SCIE 2025年第10期40-45,共6页
BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or ischemia.This syndrome is commonly an indication for surgica... BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or ischemia.This syndrome is commonly an indication for surgical intervention but has not been determined as a postoperative complication following surgery for lumbar spine disease.CASE SUMMARY To report the case of a 54-year-old male patient who had CES following spinal surgery,with no obvious compression lesions found during re-exploration,suggesting that vascular insufficiency may have contributed to the condition.Furthermore,a series of urodynamic studies on bladder recovery patterns in such complications have also been investigated.CONCLUSION Postoperative CES requires urgent imaging and exploration to rule out compression;noncompressive cases,including vascular insufficiency may performed conservative management. 展开更多
关键词 Cauda equina syndrome Lumbar spine surgery Urinary retention Urodynamic study Postoperative complication Case report
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Teriparatide as a non-surgical salvage therapy for prolonged humerus fracture nonunion:A case report and literature review
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作者 Shao-Han Guo Chong Li +2 位作者 Yi-Jun Gao Zhen Zhang Ke Lu 《World Journal of Orthopedics》 2025年第1期79-85,共7页
BACKGROUND Fracture nonunion represents a challenging complication during fracture repair,often necessitating surgical intervention.Teriparatide,a recombinant human parathyroid hormone,has demonstrated promise in enha... BACKGROUND Fracture nonunion represents a challenging complication during fracture repair,often necessitating surgical intervention.Teriparatide,a recombinant human parathyroid hormone,has demonstrated promise in enhancing fracture healing,although its efficacy in treating established nonunion remains under investigation.CASE SUMMARY We report a case of a 27-year-old male who presented with a right humerus fracture following a traffic accident.Despite undergoing open reduction and internal fixation,the fracture resulted in a delayed union and subsequent nonunion.After 4 years of conservative management,teriparatide treatment was initiated due to persistent nonunion.Teriparatide injections were administered daily for 6 months,resulting in complete fracture healing and resolution of pain.CONCLUSION Our case demonstrates the successful use of teriparatide in treating a prolonged nonunion of a humerus fracture.Teriparatide may provide a valuable therapeutic option for established bone nonunion,even in cases that have not responded to conservative treatments. 展开更多
关键词 TERIPARATIDE Humerus fracture nonunion fracture healing Prolonged nonunion Osteoanabolic therapy Bone regeneration Case report
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Effect of extended nursing based on self-efficacy theory on the anxiety of patients with intertrochanteric fracture
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作者 You-Mei Yao Xue-Yun Shao +1 位作者 Lin-Li Sha Lin-Lin Qian 《World Journal of Psychiatry》 2025年第2期92-99,共8页
BACKGROUND Extended care based on self-efficacy theory to elderly patients with intertrochanteric fractures will provide data reference to optimize the care plan of these patients,reduce patients’concurrent mental di... BACKGROUND Extended care based on self-efficacy theory to elderly patients with intertrochanteric fractures will provide data reference to optimize the care plan of these patients,reduce patients’concurrent mental diseases,and improve prognosis.AIM To analyze the value of extended nursing based on the self-efficacy theory in older patients with intertrochanteric fractures.METHODS Older patients with intertrochanteric fractures(n=88)admitted to our hospital between January 2021 and December 2024 were randomly divided into two groups-the control group(n=44,routine nursing)and the observation group(n=44,extended nursing)-via balloting and treated for 12 weeks.The mental state,pain severity,limb function,and self-nursing ability of all patients before and after nursing were analyzed.RESULTS After nursing,the Hamilton Anxiety Scale and General Self-Efficacy Scale scores of patients in the two groups improved.Notably,Hamilton Anxiety Scale and General Self-Efficacy Scale scores in the observation group were lower and higher,respectively,than those in the control group(P<0.05).The pain severity in the observation group(2.64±0.22)was lower than that in the control group(2.85±0.41)(P<0.05).The recovery rate of limb function was higher in the observation group than in the control group(P<0.05).In addition,the self-nursing ability scores of the patients in both groups increased,with a significantly higher score in the observation group(P<0.05).CONCLUSION Extended nursing based on the self-efficacy theory can significantly improve mental state,relieve pain,and promote the recovery of limb function and self-nursing ability in older patients with intertrochanteric fractures. 展开更多
关键词 Self-efficacy theory Extended nursing Intertrochanteric fractures Mental health CLINIC
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An adjustable bio-sealing method for rock fracture leakage mitigation
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作者 Zhihao Dong Xiaohua Pan +2 位作者 Chaosheng Tang Chao Lv Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期220-232,共13页
This study proposed a repeated adjustable mixture injection strategy(RAM)based microbial induced carbonate precipitation(MICP)for efficient mitigation of rock fracture leakage.Granite fractures with small apertures we... This study proposed a repeated adjustable mixture injection strategy(RAM)based microbial induced carbonate precipitation(MICP)for efficient mitigation of rock fracture leakage.Granite fractures with small apertures were investigated,and bio-sealing experiments were conducted using five different cementation solution(CS)concentrations(0.25−2 M).The results showed that the RAM-based bio-sealing method can seal and bond the small aperture rock fractures with high efficiency and uniform precipitation by adjusting the CS concentration.The RAM-based bio-sealing mechanism is attributed to the following four stages:(1)fixation of bacterial flocs onto the fracture surfaces,(2)precipitation of CaCO3 onto the fracture surfaces,(3)growth of pre-precipitated CaCO3 and adhesion of new-suspended CaCO3,and(4)bridging and clogging processes.The optimal CS concentration of 1 M resulted in a fracture filling rate up to 85%,a transmissivity reduction of 4 orders of magnitude,and a shear strength ranging from 512 kPa to 688 kPa.The bio-sealing effect was found to be influenced by the CS concentration on bacterial attachment,calcium carbonate yield and calcium carbonate bulk density.The CS concentration of 1 M promoted bacterial attachment,and increased calcium carbonate yield as well as calcium carbonate bulk density,while concentrations above 1 M had the opposite effect.The bulk density of calcium carbonate played a crucial role in the sealing and bonding performance of bio-sealed fractures,particularly at comparable filling ratios and bridging areas.The bulk density was regulated by the size of calcium carbonate crystals and was determined by Ca2+concentration in the CS.This study provides valuable insights into the RAM-based bio-sealing method,highlighting its potential for efficient rock fracture leakage mitigation through precise control of CS concentration and understanding the underlying mechanisms. 展开更多
关键词 MICP Rock fracture Hydraulic and mechanical performance Bio-sealing
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Assessment of the hip-spine relationship in total hip arthroplasty for childhood hip disorders sequelae
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作者 Cong-Ke Shu Hai-Song Liang +2 位作者 Xin-Wen Bai Yu Deng Qi-Long Jiang 《World Journal of Orthopedics》 2025年第1期86-88,共3页
In this article,we comment on the article by Oommen et al.Oommen et al provided a comprehensive overview of the management of hip centre restoration in total hip arthroplasty(THA)for childhood hip disorder sequelae.Gi... In this article,we comment on the article by Oommen et al.Oommen et al provided a comprehensive overview of the management of hip centre restoration in total hip arthroplasty(THA)for childhood hip disorder sequelae.Given the developmental disparity in this population,specific preoperative planning is an essential prerequisite for the success of THA procedures.In the review by Oommen et al,assessments of acetabular and femoral anatomic variations were fully described.However,spinal malalignment and stiffness are common in physical and radiological examinations and should be taken into careful consideration when planning surgical procedures.Poor outcomes of THA for patients with comorbid hip and spinopelvic pathologies have been widely reported,especially for hips with childhood disorder sequelae.Therefore,in this editorial,we would like to emphasize the need for a thorough hip-spine evaluation of patients with childhood hip disorder sequelae before THA. 展开更多
关键词 Relationship between the hip and spine Total hip arthroplasty Childhood disorder sequelae Preoperative assessment Hip-spine classification
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Association between body mass index and lumbar spine volumetric bone mineral density in diabetic and non-diabetic patients
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作者 Fang Lv Xiao-Ling Cai +4 位作者 Xiu-Ying Zhang Xiang-Hai Zhou Xue-Yao Han Yu-Feng Li Li-Nong Ji 《World Journal of Diabetes》 2025年第2期103-113,共11页
BACKGROUND The association between body mass index(BMI)and bone mineral density(BMD)has shown inconsistent results,varying by sex and skeletal site.Despite normal or elevated bone mass,individuals with type 2 diabetes... BACKGROUND The association between body mass index(BMI)and bone mineral density(BMD)has shown inconsistent results,varying by sex and skeletal site.Despite normal or elevated bone mass,individuals with type 2 diabetes have an increased risk of hip and vertebral fractures.AIM To assess lumbar spine trabecular volumetric BMD(vBMD)across different BMI categories in individuals with and without diabetes.METHODS This cross-sectional study included 966 men over 50 years old and 1001 postmenopausal women from the Pinggu Metabolic Disease Study.The vBMD of lumbar vertebrae 2 through 4 was measured using quantitative computed tomography.Total adipose tissue,subcutaneous adipose tissue(SAT),visceral adipose tissue(VAT),and lumbar skeletal muscle area were also quantified.RESULTS In men with obesity(P=0.038)and overweight(P=0.032),vBMD was significantly higher in the diabetes group compared to non-diabetic men.After adjusting for age and sex,no significant saturation effect between BMI and BMD was found in participants with diabetes or in women without diabetes.However,a BMI threshold of 22.33 kg/m²indicated a saturation point for vBMD in nondiabetic men.Independent predictors of vBMD in men included age(r=-0.387,P<0.001),BMI(r=0.130,P=0.004),and VAT(r=-0.145,P=0.001).For women,significant predictors were age(r=-0.594,P<0.001),BMI(r=0.157,P=0.004),VAT(r=-0.112,P=0.001),and SAT(r=-0.068,P=0.035).CONCLUSION The relationship between BMI and trabecular vBMD differs in individuals with and without diabetes.Overweight and obese men with diabetes exhibit higher vBMD. 展开更多
关键词 Obesity and overweight Body mass index DIABETES Lumbar spine volumetric bone mineral density Quantitative computed tomography
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Using fracture mechanics method to analyze the failure mechanism and equilibrium equation of interfacial loess-mudstone landslides
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作者 LI Shuanhu LI Chi GAO Yu 《Journal of Mountain Science》 2025年第1期156-166,共11页
Loess-mudstone landslides are common in the Loess Plateau.Investigations into the mechanical theory of loess-mudstone landslides have become a challenging undertaking due to the distinctive interfacial properties of l... Loess-mudstone landslides are common in the Loess Plateau.Investigations into the mechanical theory of loess-mudstone landslides have become a challenging undertaking due to the distinctive interfacial properties of loess-mudstone and the unique water sensitivity characteristics of mudstone.Hence,it is imperative to develop innovative mechanical models and mathematical equations specifically tailored to loess-mudstone landslides.In this study,we analyze the fracture mechanism of the loess-mudstone sliding zone using plastic fracture mechanics and develop a unique fracture yield model.To calculate the energy release rate during the expansion of the loess-mudstone interface tip region,the shear fracture energy G is applied,which reflects both the yield failure criterion and the fracture failure criterion.To better understand the instability mechanism of loess-mudstone landslides,equilibrium equations based on G are established for tractive,compressive,and tensile loess-mudstone landslides.Based on the equilibrium equation,the critical length Lc of the sliding zone can be used for the safety evaluation of loess-mudstone landslides.In this way,this study proposes a new method for determining the failure mechanism and equilibrium equation of loessmudstone landslides,which resolves their starting mechanism,mechanical equilibrium equations,and safety evaluation indicators,thus justifying the scientific significance and practical value of this research. 展开更多
关键词 Loess-mudstone landslide Failure mechanism Shear fracture energy Equilibrium equation Safety factor
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High cycle fatigue performance at 650℃and corresponding fracture behaviors of GH4169 joint produced by linear friction welding
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作者 Shitong MA Xiawei YANG +6 位作者 Zhenguo GUO Yu SU Xinyuan HE Ju LI Jun TAO Bo XIAO Wenya LI 《Chinese Journal of Aeronautics》 2025年第1期622-637,共16页
GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 58... GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,respectively.The HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of joint.The microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of matrix.The Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds 0.4.In addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains. 展开更多
关键词 High cycle fatigue GH4169 superalloy Linear friction welding fracture mechanism Microstructure evolution
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An extended discontinuous deformation analysis for simulation of grouting reinforcement in a water-rich fractured rock tunnel
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作者 Jingyao Gao Siyu Peng +1 位作者 Guangqi Chen Hongyun Fan 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期168-186,共19页
Grouting has been the most effective approach to mitigate water inrush disasters in underground engineering due to its ability to plug groundwater and enhance rock strength.Nevertheless,there is a lack of potent numer... Grouting has been the most effective approach to mitigate water inrush disasters in underground engineering due to its ability to plug groundwater and enhance rock strength.Nevertheless,there is a lack of potent numerical tools for assessing the grouting effectiveness in water-rich fractured strata.In this study,the hydro-mechanical coupled discontinuous deformation analysis(HM-DDA)is inaugurally extended to simulate the grouting process in a water-rich discrete fracture network(DFN),including the slurry migration,fracture dilation,water plugging in a seepage field,and joint reinforcement after coagulation.To validate the capabilities of the developed method,several numerical examples are conducted incorporating the Newtonian fluid and Bingham slurry.The simulation results closely align with the analytical solutions.Additionally,a set of compression tests is conducted on the fresh and grouted rock specimens to verify the reinforcement method and calibrate the rational properties of reinforced joints.An engineering-scale model based on a real water inrush case of the Yonglian tunnel in a water-rich fractured zone has been established.The model demonstrates the effectiveness of grouting reinforcement in mitigating water inrush disaster.The results indicate that increased grouting pressure greatly affects the regulation of water outflow from the tunnel face and the prevention of rock detachment face after excavation. 展开更多
关键词 Discontinuous deformation analysis(DDA) Water-rich fractured rock tunnel Grouting reinforcement Water inrush disaster
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Deformation mechanism and NPR anchor cable truss coupling support in tunnel through fault fracture zone
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作者 HUO Shusen TAO Zhigang +2 位作者 HE Manchao WANG Fengnian XU Chuang 《Journal of Mountain Science》 2025年第1期354-374,共21页
To address the issue of extensive deformation in the Tabaiyi Tunnel caused by the fault zone,nuclear magnetic resonance(NMR)technology was employed to analyze the physical and mechanical properties of waterabsorbing m... To address the issue of extensive deformation in the Tabaiyi Tunnel caused by the fault zone,nuclear magnetic resonance(NMR)technology was employed to analyze the physical and mechanical properties of waterabsorbing mudstone.This analysis aimed to understand the mechanism behind the significant deformations.Drawing from the principle of excavation stress compensation,a support scheme featuring NPR anchorcables and an asymmetric truss support system was devised.To validate the scheme,numerical analysis using a combination of the Discrete Element Method(DEM)-Finite Element Method(FEM)was conducted.Additionally,similar material model tests and engineering measurements were carried out.Field experiments were also performed to evaluate the NPR anchor-cable and truss support system,focusing on anchor cable forces,pressures between the truss and surrounding rock,pressures between the initial support and secondary lining,as well as the magnitude of settlement and convergence deformation in the surrounding rock.The results indicate that the waterinduced expansion of clay minerals,resulting from damage caused by fissure water,accelerated the softening of the mudstone's internal structure,leading to significant deformations in the Tabaiyi Tunnel under high tectonic stress.The original support design fell short as the length of the anchor rods was smaller than the expansion depth of the plastic zone.As a result,the initial support structure bore the entire load from the surrounding rock,and a non-coupled deformation contact was observed between the double-arch truss and the surrounding rock.The adoption of NPR asymmetric anchor-cable support effectively restrained the expansion and asymmetric distribution characteristics of the plastic zone.Considering the mechanical degradation caused by water absorption in mudstone,the rigid constraint provided by the truss proved crucial for controlling the stability of the surrounding rock.These research findings hold significant implications for managing large deformations in soft rock tunnels situated within fractured zones under high tectonic stress conditions. 展开更多
关键词 Fault fracture zone Large deformation Nuclear magnetic resonance NPR anchor cable truss support Coupled simulation
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Mesoscopic fracture damage evolution and fractal damage constitutive model of heat-treated red sandstone under direct tensile impact loadings
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作者 Shi Liu Yu Jia +1 位作者 Yue Zhai Shaoxu Hao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期323-340,共18页
Understanding the mesoscopic tensile fracture damage of rock is the basis of evaluating the deterioration process of mechanical properties of heat-damaged rock. For this, tensile tests of rocks under high-temperature ... Understanding the mesoscopic tensile fracture damage of rock is the basis of evaluating the deterioration process of mechanical properties of heat-damaged rock. For this, tensile tests of rocks under high-temperature treatment were conducted with a ϕ75 mm split Hopkinson tension bar (SHTB) to investigate the mesoscopic fracture and damage properties of rock. An improved scanning electron microscopy (SEM) experimental method was used to analyze the tensile fracture surfaces of rock samples. Qualitative and quantitative analyses were performed to assess evolution of mesoscopic damage of heat-damaged rock under tensile loading. A constitutive model describing the mesoscopic fractal damage under thermo-mechanical coupling was established. The results showed that the high temperatures significantly reduced the tensile strength and fracture surface roughness of the red sandstone. The three-dimensional (3D) reconstruction of the fracture surface of the samples that experienced tensile failure at 900 °C showed a flat surface. The standard deviation of elevation and slope angle of specimen fracture surface first increased and then decreased with increasing temperature. The threshold for brittle fracture of the heat-damaged red sandstone specimens was 600 °C. Beyond this threshold temperature, local ductile fracture occurred, resulting in plastic deformation of the fracture surface during tensile fracturing. With increase of temperature, the internal meso-structure of samples was strengthened slightly at first and then deteriorated gradually, which was consistent with the change of macroscopic mechanical properties of red sandstone. The mesoscopic characteristics, such as the number, mean side length, maximum area, porosity, and fractal dimension of crack, exhibited an initial decline, followed by a gradual increase. The development of microcracks in samples had significant influence on mesoscopic fractal dimension. The mesoscopic fractal characteristics were used to establish a mesoscopic fractal damage constitutive model for red sandstone, and the agreement between the theoretical and experimental results validated the proposed model. 展开更多
关键词 High temperature rock mechanics Dynamic direct tension Red sandstone Mesoscopic fracture mechanism Fractal damage constitutive model
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Methods of predicting vertebral body fractures of the lumbar spine 被引量:6
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作者 Gurudattsingh B Sisodia 《World Journal of Orthopedics》 2013年第4期241-247,共7页
Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone minera... Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone mineral density(BMD), which may be applied in order to predict VB failure load and fracture risk. The most representative models are those that take account of normal spinal kinetics and assess the contribution of the cortical shell to vertebral strength. Overall, predictive models for VB fracture risk should encompass a range of important parameters including BMD, geometric measures and patient-specific factors. As interventions like vertebroplasty increase in popularity for VB fracture treatment and prevention, such models are likely to play a significant role in the clinical decision-making process. More biomechanical research is required, however, to reduce the risks of post-operative adjacent VB fractures. 展开更多
关键词 LUMBAR spine VERTEBRAL body fracture Prediction Model Bone MINERAL density OSTEOPOROSIS
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Application of the Modality of Multiple Disciplinary Team for a Perioperative Patient with Suspected Novel Coronavirus Pneumonia and Cervical Spine Fracture in Nursing 被引量:2
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作者 Yuanli Chen Yingying Zhang +3 位作者 Huijun Zhou Wenzhen Li Ruiting Hao Liang Peng 《International Journal of Clinical Medicine》 2020年第12期769-777,共9页
With the explosive spread of novel coronavirus pneumonia, a major public major public health emergency has been declared around the world. Our country has come to a crucial stage of “external defense input, internal ... With the explosive spread of novel coronavirus pneumonia, a major public major public health emergency has been declared around the world. Our country has come to a crucial stage of “external defense input, internal defense rebound” and strict quarantine measures are taken in all ports of entry throughout the country. Operations on patients with cervical spine during the quarantine, which not only increases the risk of surgical treatment, but also increases the difficulty of perioperative nursing. The objective is to explore the result of application of the modality of multiple disciplinary team for a perioperative patient with suspected novel coronavirus pneumonia and cervical spine fracture in nursing. The patient’s condition and nursing measures are studied and discussed from various specialist angle through the multidisciplinary team established by the isolation ward, orthopedics department, emergency department, anesthesiology department, operating room, rehabilitation department, psychology department and so on, and the overall and personalized surgical and nursing planning is formed through interdisciplinary advice. The nursing experience is summarized in this paper. 展开更多
关键词 Multiple Disciplinary Team Suspected Novel Coronavirus Pneumonia Cervical spine fracture Perioperative Period NURSING
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Cervical spine fractures in osteopetrosis:a case report and review of the literature 被引量:3
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作者 Arjang Ahmadpour Amir Goodarzi +2 位作者 Darrin J.Lee Ripul R.Panchal Kee D.Kim 《The Journal of Biomedical Research》 CAS CSCD 2018年第1期68-76,共9页
While management of appendicular fractures has been well described in the setting of osteopetrosis, there is limited information on managing fractures of the axial spine. Here we present an osteopetrotic patient with ... While management of appendicular fractures has been well described in the setting of osteopetrosis, there is limited information on managing fractures of the axial spine. Here we present an osteopetrotic patient with multiple traumatic multiple, comminuted, unstable cervical spinal fractures managed with non-operative stabilization, and provide a review of the pathophysiology, genetic characteristics, and special considerations that must be explored when determining operative versus non-operative management of spinal injury in osteopetrosis. A PubMed query was performed for English articles in the literature published up to June 2016, and used the following search terms alone and in combination: "osteopetrosis", "spine", "fractures", "osteoclasts", and "operative management". Within four months after initial injury, treatment with halo vest allowed for adequate healing. The patient was asymptomatic with cervical spine dynamic radiographs confirming stability at four months. On four-year follow up examination, the patient remained without neck pain, and CT scan demonstrated partially sclerotic fracture lines with appropriate anatomical alignment. In conclusion, external halo stabilization may be an effective option for treatment of multiple unstable acute traumatic cervical spine fractures in patients with osteopetrosis. Given the challenge of surgical stabilization in osteopetrosis, further research is necessary to elucidate the optimal form of treatment in this select patient population. 展开更多
关键词 osteopetrosis spine fractures osteoclasts operative management
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Blunt Traumatic Cervical Spine Fractures in Iran 被引量:2
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作者 Soheil Saadat Aliashraf Eghbali +2 位作者 Alexander R. Vaccaro Mahdi Sharif-Alhoseini Vafa Rahimi-Movaghar 《Surgical Science》 2011年第8期407-413,共7页
Background: Blunt traumatic cervical spine fractures (TCSF) are serious injuries which may be associated with considerable mortality and morbidity. We describe the epidemiology of blunt traumatic cervical spine fractu... Background: Blunt traumatic cervical spine fractures (TCSF) are serious injuries which may be associated with considerable mortality and morbidity. We describe the epidemiology of blunt traumatic cervical spine fracture in Iran over a definable time period. Methods: In a cross-sectional study, the data including the distribution of TCSF, demographics, mechanisms, abbreviated injury scale (AIS), spinal cord associated injuries and final outcome of patients, was extracted from the Iranian national trauma registry database in target hospitals in eight major cities of Iran from 1999 to 2004. The Chi square test was used to compare mortality and one-way ANOVA was used to compare ISS amongst the categories of TCSF. Results: TCSF was identified in 120 cases, of these 70.8% were male. Their mean age was 36.6 ± 17.2 years. The overall incidence of TCSF among all trauma patients was 0.7% (95%CI: 0.61% - 0.88%). The TCSF incidence among all spine fractured patients was 19.38% (95%CI: 16.34% - 22.72%). The most common mechanism of TCSF was a motor vehicle collision (66.7%). The overall percentage of in-hospital death for TCSF was 12.6%. There were no statistically significant difference in death and injury severity scores (ISS) among TCSF categories (p > 0.05). Spinal cord and root injuries occurred in 34.9% and 2.4% of TCSF, respectively. Conclusions: Preventive strategies need to be developed in order to reduce the number and severity of TCSF in the general Iranian population. 展开更多
关键词 CERVICAL spine fractureS Iran Motor Vehicle CRASH TRAUMA
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FRACTURE序列在中轴型脊柱关节炎骶髂关节结构性病变中的诊断价值 被引量:1
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作者 章忆惠 程艺璇 +4 位作者 徐磊 徐凌霄 谈文峰 王梦悦 祁良 《放射学实践》 CSCD 北大核心 2024年第7期929-934,共6页
目的:评估限制回波间隔的快速梯度回波类CT成像(FRACTURE)序列在检测中轴型脊柱关节炎(SpA)骶髂关节结构病变中的诊断价值。方法:回顾性分析83例确诊中轴型SpA患者在2021年12月-2022年8月进行骶髂关节MRI和CT检查的影像资料。评估图像包... 目的:评估限制回波间隔的快速梯度回波类CT成像(FRACTURE)序列在检测中轴型脊柱关节炎(SpA)骶髂关节结构病变中的诊断价值。方法:回顾性分析83例确诊中轴型SpA患者在2021年12月-2022年8月进行骶髂关节MRI和CT检查的影像资料。评估图像包括FRACTURE、T_(1)WI序列和CT平扫图像。对骶髂关节的影像图像进行结构性病变评分:关节间隙变化(0~5分)、骨质侵蚀(0~3分)和骨质硬化(0~2分)。根据修改后的纽约标准评分系统对骶髂关节炎进行综合评分。结果:总共有166个骶髂关节图像(83名受试者)可供分析。以CT图像作为参考标准,FRACTURE序列在关节间隙改变、骨质侵蚀、骨质硬化和骶髂关节炎综合评分与CT结果表现出较高的一致性,AUC分别为0.908、0.943、0.918和0.944。与T_(1)WI相比,FRACTURE在关节间隙变化(91.8%vs.70.5%)、骨质侵蚀(93.3%vs.56.4%)、骨质硬化(94%vs.77.6%)和骶髂关节炎综合评分(98.9%vs.75.3%)方面具有更高的诊断准确性。结论:FRACTURE成像可以评估中轴型SpA患者骶髂关节的结构性病变,并显示出良好的诊断性能。 展开更多
关键词 fracture序列 骶髂关节 脊柱关节病 磁共振成像 体层摄影术 X线计算机
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