Lost circulation critically jeopardizes drilling safety and efficiency,and remains an unresolved challenge in oil and gas engineering.In this paper,by utilizing the self-developed dynamic plugging apparatus and synthe...Lost circulation critically jeopardizes drilling safety and efficiency,and remains an unresolved challenge in oil and gas engineering.In this paper,by utilizing the self-developed dynamic plugging apparatus and synthetic cores containing large-scale fractures,experimental research on the circulation plugging of different materials was conducted.Based on the D90 rule and fracture mechanical aperture model,we analyze the location of plugging layer under dynamic plugging mechanism.By setting different parameters of fracture width and injection pressure,the laws of cyclic plugging time,pressure bearing capacity and plugging layers formation were investigated.The results show that the comprehensive analysis of particle size and fracture aperture provides an accurate judgment of the entrance-plugging phenomenon.The bridging of solid materials in the leakage channel is a gradual process,and the formation of a stable plug requires 2–3 plug-leakage cycles.The first and second cyclic plugging time was positively correlated with the fracture width.Different scales of fractures were successfully plugged with the bearing pressure greater than 6 MPa,but there were significant differences in the composition of the plugging layer.The experimental results can effectively prove that the utilized plugging agent is effective and provides an effective reference for dynamic plugging operation.展开更多
Coral reef limestone(CRL)constitutes a distinctive marine carbonate formation with complex mechanical properties.This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experime...Coral reef limestone(CRL)constitutes a distinctive marine carbonate formation with complex mechanical properties.This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experimental testing,digital core technology,and theoretical modelling.Two CRL types with contrasting mesostructures were characterized across three scales.Macroscopically,CRL-I and CRL-II exhibited mean compressive strengths of 8.46 and 5.17 MPa,respectively.Mesoscopically,CRL-I featured small-scale highly interconnected pores,whilst CRL-II developed larger stratified pores with diminished connectivity.Microscopically,both CRL matrices demonstrated remarkable similarity in mineral composition and mechanical properties.A novel voxel average-based digital core scaling methodology was developed to facilitate numerical simulation of cross-scale damage processes,revealing network-progressive failure in CRL-I versus directional-brittle failure in CRL-II.Furthermore,a damage statistical constitutive model based on digital core technology and mesoscopic homogenisation theory established quantitative relationships between microelement strength distribution and macroscopic mechanical behavior.These findings illuminate the fundamental mechanisms through which mesoscopic structure governs the macroscopic mechanical properties of CRL.展开更多
Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer ...Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces.展开更多
Prepulse combined hydraulic fracturing facilitates the development of fracture networks by integrating prepulse hydraulic loading with conventional hydraulic fracturing.The formation mechanisms of fracture networks be...Prepulse combined hydraulic fracturing facilitates the development of fracture networks by integrating prepulse hydraulic loading with conventional hydraulic fracturing.The formation mechanisms of fracture networks between hydraulic and pre-existing fractures under different prepulse loading parameters remain unclear.This research investigates the impact of prepulse loading parameters,including the prepulse loading number ratio(C),prepulse loading stress ratio(S),and prepulse loading frequency(f),on the formation of fracture networks between hydraulic and pre-existing fractures,using both experimental and numerical methods.The results suggest that low prepulse loading stress ratios and high prepulse loading number ratios are advantageous loading modes.Multiple hydraulic fractures are generated in the specimen under the advantageous loading modes,facilitating the development of a complex fracture network.Fatigue damage occurs in the specimen at the prepulse loading stage.The high water pressure at the secondary conventional hydraulic fracturing promotes the growth of hydraulic fractures along the damage zones.This allows the hydraulic fractures to propagate deeply and interact with pre-existing fractures.Under advantageous loading conditions,multiple hydraulic fractures can extend to pre-existing fractures,and these hydraulic fractures penetrate or propagate along pre-existing fractures.Especially when the approach angle is large,the damage range in the specimen during the prepulse loading stage increases,resulting in the formation of more hydraulic fractures.展开更多
BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appea...BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures.展开更多
Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some sho...Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.展开更多
BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term outco...BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term outcomes.Existing studies have investigated risk factors for POD,but most are limited by single-factor analyses or small sample sizes.This study systematically determines independent risk factors using large-scale data and machine learning techniques and develops a validated nomogram model to support early prediction and management of POD.AIM To investigate POD incidence in elderly patients with HF and the independent risk factors,according to which a nomogram prediction model was developed and validated.METHODS This retrospective study included elderly patients with HF who were surgically treated in Dongying People’sHospital from April 2018 to April 2022. The endpoint event includes POD. They were categorized into themodeling and validation cohorts in a 7:3 ratio by randomization. Both cohorts were further classified into thedelirium and normal (non-delirium) groups according to the presence or absence of the endpoint event. Theincidence of POD was calculated, and logistic multivariate analysis was conducted to determine the independentrisk factors. The calibration curve and the Hosmer-Lemeshow test as well as the net benefit threshold probabilityinterval by the decision curve were utilized to statistically validate the accuracy of the nomogram predictionmodel, developed according to each factor’s influence intensity.RESULTSThis study included 532 elderly patients with HF, with an overall POD incidence of 14.85%. The comparison ofbaseline data with perioperative indicators revealed statistical differences in age (P < 0.001), number of comorbidities(P = 0.042), American Society of Anesthesiologists grading (P = 0.004), preoperative red blood cell(RBC) count (P < 0.001), preoperative albumin (P < 0.001), preoperative hemoglobin (P < 0.001), preoperativeplatelet count (P < 0.001), intraoperative blood loss (P < 0.001), RBC transfusion of ≥ 2 units (P = 0.001), andpostoperative intensive care unit care (P < 0.001) between the delirium and non-delirium groups. The participantswere randomized to a training group (n = 372) and a validation group (n = 160). A score-risk nomogram predictionmodel was developed after screening key POD features using Lasso regression, support vector machine, and therandom forest method. The nomogram showed excellent discriminatory capacity with area under the curve of0.833 [95% confidence interval (CI) interval: 0.774-0.888] in the training group and 0.850 (95%CI: 0.718-0.982) in thevalidation group. Calibration curves demonstrated good agreement between predicted and actual probabilities,and decision curve analysis confirmed clinical net benefits within risk thresholds of 0%-30% and 0%-36%, respectively.The model has strong accuracy and clinical utility for predicting the risk of POD.CONCLUSIONThis study reveals cognitive impairment history, American Society of Anesthesiologists grade of > 2, RBCtransfusion of ≥ 2 units, postoperative intensive care unit care, and preoperative hemoglobin level as independentrisk factors for POD in elderly patients with HF. The developed nomogram model demonstrates excellent accuracyand stability in predicting the risk of POD, which is recommended to be applied in clinical practice to optimizepostoperative management and reduce delirium incidence.展开更多
Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior an...Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior and its influencing factors are important for the long-term performance assessment of DGRs.We designed multistage mechanical(M)shear tests and thermomechanical(TM)shear tests on three 100 mm-cubic granite specimens,each containing a single inclined sawcut fracture with distinct microroughness of 8-15μm.M test results have shown that the static friction coefficient of the granite fracture decreases in proportion to the increase in the logarithm of the loading rate within the range of 1-15 kPa/s.For the given heating and boundary conditions,thermal loading rate,i.e.,thermal stress increment with heating time,is measured to be around 1 kPa/s in the fractured granite.Thermoshearing can be well predicted by the linear Mohr-Coulomb failure envelope deduced from M shear tests employing a loading rate that is comparable with the thermal loading rate.The granite fractures exhibited two distinct slip patterns during the mechanical shearing,i.e.,stick-slip observed in the smooth fracture and stable sliding in the relatively rough surface.In contrast,the mechanical loading rate(1-15 kPa/s)investigated in this study appears to not influence the slip pattern.Unlike those in M shear tests,thermoshearing in both smooth and relatively rough fractures show stable sliding with a very slow peak velocity of around 0.002μm/s.展开更多
In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accurac...In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods.展开更多
The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method f...The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception.展开更多
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and...A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread.展开更多
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
Introduction: Open leg fracture is a diaphyseal or metaphyseal, extra-articular fracture of one or both leg bones, with communication between the fracture site and the external environment. To provide a broader contex...Introduction: Open leg fracture is a diaphyseal or metaphyseal, extra-articular fracture of one or both leg bones, with communication between the fracture site and the external environment. To provide a broader context, studies conducted globally have highlighted the significance of understanding open leg fractures due to their complex management and potential complications. Previous research in Africa and Europe provides comparative data that emphasizes regional differences in fracture types, causes, and treatment outcomes. This study aims to contribute to improving the management of theses fractures in Niger. Materials and Methods: This was a prospective, descriptive study carried out in the Traumatology-Orthopedics Department of the Zinder National Hospital, Niger, from December 8, 2020 to June 8, 2022 (18 months). We included all patients over 15 years of age in whom an open leg fracture was diagnosed and managed. Inclusion criteria focused on patients aged over 15 years with confirmed diagnoses of open leg fractures. Results: Over an 18-month period, the frequency of open leg fractures was 16.28%. There was a predominance of males (85.93% or n = 116). The average age of patients was 31.79 years. Road accidents were the primary circumstance of occurrence (93.33% or n = 126). The fracture line was simple in 74 patients (54.81%) and complex in 61 cases (45.19%). Surgically, the external fixator was used in 78 cases (57.80%). Postoperative follow-up was mostly straightforward. The main complications were infection (4 cases) and delayed consolidation (4 cases). Conclusion: Open leg fractures in adults are frequent at Zinder National Hospital. Public road accidents were the main cause of occurrence. An external fixator osteosynthesis was the most commonly used surgical option. These findings have important implications for healthcare policy, particularly in improving trauma care infrastructure and road safety initiatives in Niger. Future studies should prioritize the development of standardized treatment protocols and investigate the long-term outcomes of different surgical approaches.展开更多
This article focuses on the factors influencing fracture nonunion, classification and treatment. The article emphasizes the importance of understanding the influencing factors and mechanisms of fracture healing for de...This article focuses on the factors influencing fracture nonunion, classification and treatment. The article emphasizes the importance of understanding the influencing factors and mechanisms of fracture healing for developing effective treatment strategies and improving patients’ quality of life. It also points out the challenges of current treatment, such as patient compliance and limitations of treatment methods, and looks at future treatment directions.展开更多
Shale reservoirs are characterized by numerous geological discontinuities,such as bedding planes,and exhibit pronounced heterogeneity across rock layers separated by these planes.Bedding planes often possess distinct ...Shale reservoirs are characterized by numerous geological discontinuities,such as bedding planes,and exhibit pronounced heterogeneity across rock layers separated by these planes.Bedding planes often possess distinct mechanical properties compared to the surrounding rock matrix,particularly in terms of damage and fracture behavior.Consequently,vertical propagation of hydraulic fractures is influenced by both bedding planes and the heterogeneity.In this study,a numerical investigation into the height growth of hydraulic fractures was conducted using the finite element method,incorporating zero-thickness cohesive elements.The analysis explored the effects of bedding planes,toughness contrasts between layers,and variations in in-situ stress across different strata.The results reveal that hydraulic fractures are more likely to propagate along bedding planes instead of traversing them and extending vertically into barrier layers when(1)bedding strength is low,(2)stress contrast between layers is high,and(3)toughness contrast is significant.Furthermore,for a given bedding strength,increased stress contrast or higher toughness contrast between layers elevate hydraulic fracture extension pressure.When a substantial stress difference exists between layers(Lc 0.4),hydraulic=fractures preferentially propagate along bedding planes.Conversely,as bedding strength increases,the propagation distance along bedding planes decreases,accompanied by an amplified horizontal compressive stress field.Notably,when the stress difference is sufficiently small(SD a phenomenon termed“stress rolling”emerges,wherein<-0.2),hydraulic fractures deviate from vertical growth and instead extend along a near-horizontal trajectory.展开更多
Hydraulic fracturing is a crucial technique for efficient development of coal reservoirs.Coal rocks typically contain a high density of natural fractures,which serve as conduits for fracturing fluid.Upon injection,the...Hydraulic fracturing is a crucial technique for efficient development of coal reservoirs.Coal rocks typically contain a high density of natural fractures,which serve as conduits for fracturing fluid.Upon injection,the fluid infiltrates these natural fractures and leaks out,resulting in complex fracture morphology.The prediction of hydraulic fracture network propagation for coal reservoirs has important practical significance for evaluating hydraulic fracturing.This study proposes a novel inversion method for predicting fracture networks in coal reservoirs,explicitly considering the distribution of natural fractures.The method incorporates three distinct natural fracture opening modes and employs a fractal probability function to constrain fracture propagationmorphology.Based on thismethod,the study compares hydraulic fracture networkmorphologies in coal reservoirs with andwithout the presence of natural fractures.Theresults showthatwhile both reservoir types exhibitmulti-branch fracture networks,reservoirs containing natural fractures demonstrate greater branching and a larger stimulated reservoir volume(SRV).Additionally,the study employs a fractal dimension calculation method to quantitatively describe the geometric distribution characteristics of fractures.The analysis reveals that the geometry and distribution of natural fractures,as well as reservoir geological parameters,significantly influence the fracture networkmorphology and fractal dimension.The contact angle between natural and hydraulic fractures affects propagation direction;specifically,when the contact angle isπ/2,the fractal dimension of the hydraulic fracture network is maximized.Moreover,smaller lengths and spacings of natural fracture led to higher fractal dimensions,which can significantly increase the SRV.The proposed method offers an effective tool for evaluating the hydraulic fracturing of coal reservoirs.展开更多
Background and Objectives: The distal radius fracture (DRF) is a major public health problem in northern countries. Its frequency is constantly increasing. The locked anterior plate with its well-established biomechan...Background and Objectives: The distal radius fracture (DRF) is a major public health problem in northern countries. Its frequency is constantly increasing. The locked anterior plate with its well-established biomechanical properties, offers a reliable alternative. The aim of this study was to evaluate the radiological, the functional results and to determine the factors of poor postoperative prognosis of DRF treated with Newclip radial plates®. Methodology: This prospective cohort study evaluates the radiological and functional outcames of displaced radius fractures (DRFs) in patients ≥50 years old treated with Newclip® (locked anterior plates) at the Basse-Terre Hospital in Guadeloupe from 2022 to 2024. The patients were categorized into those with epiphyseal involvement (E1 - E4) and without epiphyseal involvement (E0) based on Laulan’s MEU classification. Radiological parameters (distal radio-ulnar index (DRUI), radial inclination frant view (IRF), radial inclination sagittal view (IRS) were assessed pre and post-operatively. Functional recovery was evaluated at 12 months using the QuickDash questionnaire. Results: Falls were the most common cause of fracture. Post-operatively, SRI was the least restored parameter. Poor prognostic factor for SRI improvement included posterior commimution and unstable fractures. Factors associated with higher QuickDash scores included unstable factures, unrestored DRUI, low plate position, metaphyseal features, and ulnar features. Conclusion: The anterior locking plate osteosynthesis is reliable treatment option with excellent functional outcomes.展开更多
Periprosthetic fracture of femur is a common and complex complication after joint replacement. With the increase of operation volume, its incidence is increasing year by year. The treatment of this fracture is affecte...Periprosthetic fracture of femur is a common and complex complication after joint replacement. With the increase of operation volume, its incidence is increasing year by year. The treatment of this fracture is affected by many factors, including fracture type, prosthesis stability, patient age and comorbidities, and individualized treatment strategy is needed. In recent years, the internal fixation technology and prosthetic revision technology have made significant progress in surgical treatment, such as locking steel plate, titanium cable and bridge combined internal fixation system and other new technologies have effectively improved the treatment effect. In addition, the application of new materials and 3D printing technology, as well as the optimization of multidisciplinary cooperation mode, also provide new ideas for the treatment of complex fractures. However, there are still some problems such as inaccurate diagnosis, difficult choice of treatment options and high incidence of postoperative complications. In the future, technological innovation, the introduction of artificial intelligence and big data, and the further development of personalized treatment will bring more possibilities to improve the prognosis and quality of life of patients. This study summarizes the relevant research results and prospects the future development direction, providing references for clinical practice and subsequent research.展开更多
According to World Health Organization,one in six people will be older than 60 by 2030.The rising life expectancy is anticipated to contribute to a subsequent increase of geriatric fractures worldwide.Osteosarcopenia,...According to World Health Organization,one in six people will be older than 60 by 2030.The rising life expectancy is anticipated to contribute to a subsequent increase of geriatric fractures worldwide.Osteosarcopenia,which is the coexistence of osteoporosis and sarcopenia,greatly affects older people.Recent studies have tried to identify the prevalence of osteosarcopenia in older populations as well as its correlation with fragility fractures such as hip fractures.The latter pose a major burden on both health loss and costs worldwide.Increasing amount of evidence suggests that osteosarcopenia in patients with hip fractures contributes to higher rates of mortality and complications.At the same time,research focuses on the molecular basis of the interplay between osteoporosis and sarcopenia by utilizing genomic or proteomic approaches.These promising studies could reveal potential preventive or diagnostic biomarkers to optimize the management of osteosarcopenia in hip fractures patients.The fact that bones and muscle can also function as endocrine organs further highlights the complex relationship between osteoporosis and sarcopenia,underscoring the need for a better understanding of the role of myokines and osteokines in osteosarcopenia.Finally,the impact of osteosarcopenia on pain management and rehabilitation after hip fracture surgery,requires further assessment.展开更多
Controllable shock wave fracturing is an innovative engineering technique used for shale reservoir fracturing and reformation.Understanding the anisotropic fracture mechanism of shale under impact loading is vital for...Controllable shock wave fracturing is an innovative engineering technique used for shale reservoir fracturing and reformation.Understanding the anisotropic fracture mechanism of shale under impact loading is vital for optimizing shock wave fracturing equipment and enhancing shale oil production.In this study,using the well-known notched semi-circular bend(NSCB)sample and the novel double-edge notched flattened Brazilian disc(DNFBD)sample combined with a split Hopkinson pressure bar(SHPB),various dynamic anisotropic fracture properties of Lushan shale,including failure characteristics,fracture toughness,energy dissipation and crack propagation velocity,are comprehensively compared and discussed under mode Ⅰ and mode Ⅱ fracture scenarios.First,using a newly modified fracture criterion considering the strength anisotropy of shale,the DNFBD specimen is predicted to be a robust method for true mode Ⅱ fracture of anisotropic shale rocks.Our experimental results show that the dynamic mode Ⅱ fracture of shale induces a rougher and more complex fracture morphology and performs a higher fracture toughness or fracture energy compared to dynamic mode Ⅰ fracture.The minimal fracture toughness or fracture energy occurs in the Short-transverse orientation,while the maximal ones occur in the Divider orientation.In addition,it is interesting to find that the mode Ⅱ fracture toughness anisotropy index decreases more slowly than that in the mode Ⅰ fracture scenario.These results provide significant insights for understanding the different dynamic fracture mechanisms of anisotropic shale rocks under impact loading and have some beneficial implications for the controllable shock wave fracturing technique.展开更多
基金financially supported by National Natural Science Foundation of China(No.52422402)。
文摘Lost circulation critically jeopardizes drilling safety and efficiency,and remains an unresolved challenge in oil and gas engineering.In this paper,by utilizing the self-developed dynamic plugging apparatus and synthetic cores containing large-scale fractures,experimental research on the circulation plugging of different materials was conducted.Based on the D90 rule and fracture mechanical aperture model,we analyze the location of plugging layer under dynamic plugging mechanism.By setting different parameters of fracture width and injection pressure,the laws of cyclic plugging time,pressure bearing capacity and plugging layers formation were investigated.The results show that the comprehensive analysis of particle size and fracture aperture provides an accurate judgment of the entrance-plugging phenomenon.The bridging of solid materials in the leakage channel is a gradual process,and the formation of a stable plug requires 2–3 plug-leakage cycles.The first and second cyclic plugging time was positively correlated with the fracture width.Different scales of fractures were successfully plugged with the bearing pressure greater than 6 MPa,but there were significant differences in the composition of the plugging layer.The experimental results can effectively prove that the utilized plugging agent is effective and provides an effective reference for dynamic plugging operation.
基金the National Key Research and Development Program of China(No.2021YFC3100800)the National Natural Science Foundation of China(Nos.42407235 and 42271026)the Project of Sanya Yazhou Bay Science and Technology City(No.SCKJ-JYRC-2023-54).
文摘Coral reef limestone(CRL)constitutes a distinctive marine carbonate formation with complex mechanical properties.This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experimental testing,digital core technology,and theoretical modelling.Two CRL types with contrasting mesostructures were characterized across three scales.Macroscopically,CRL-I and CRL-II exhibited mean compressive strengths of 8.46 and 5.17 MPa,respectively.Mesoscopically,CRL-I featured small-scale highly interconnected pores,whilst CRL-II developed larger stratified pores with diminished connectivity.Microscopically,both CRL matrices demonstrated remarkable similarity in mineral composition and mechanical properties.A novel voxel average-based digital core scaling methodology was developed to facilitate numerical simulation of cross-scale damage processes,revealing network-progressive failure in CRL-I versus directional-brittle failure in CRL-II.Furthermore,a damage statistical constitutive model based on digital core technology and mesoscopic homogenisation theory established quantitative relationships between microelement strength distribution and macroscopic mechanical behavior.These findings illuminate the fundamental mechanisms through which mesoscopic structure governs the macroscopic mechanical properties of CRL.
基金Opening Foundation of Key Laboratory of Explosive Energy Utilization and Control,Anhui Province(BP20240104)Graduate Innovation Program of China University of Mining and Technology(2024WLJCRCZL049)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX24_2701)。
文摘Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces.
基金financially supported by,the Fundamental Research Funds for the Central Universities(Grant No.2023QN1064)the China Postdoctoral Science Foundation(Grant No.2023M733772)Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2023ZB847)。
文摘Prepulse combined hydraulic fracturing facilitates the development of fracture networks by integrating prepulse hydraulic loading with conventional hydraulic fracturing.The formation mechanisms of fracture networks between hydraulic and pre-existing fractures under different prepulse loading parameters remain unclear.This research investigates the impact of prepulse loading parameters,including the prepulse loading number ratio(C),prepulse loading stress ratio(S),and prepulse loading frequency(f),on the formation of fracture networks between hydraulic and pre-existing fractures,using both experimental and numerical methods.The results suggest that low prepulse loading stress ratios and high prepulse loading number ratios are advantageous loading modes.Multiple hydraulic fractures are generated in the specimen under the advantageous loading modes,facilitating the development of a complex fracture network.Fatigue damage occurs in the specimen at the prepulse loading stage.The high water pressure at the secondary conventional hydraulic fracturing promotes the growth of hydraulic fractures along the damage zones.This allows the hydraulic fractures to propagate deeply and interact with pre-existing fractures.Under advantageous loading conditions,multiple hydraulic fractures can extend to pre-existing fractures,and these hydraulic fractures penetrate or propagate along pre-existing fractures.Especially when the approach angle is large,the damage range in the specimen during the prepulse loading stage increases,resulting in the formation of more hydraulic fractures.
文摘BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures.
基金supported by the Natural Science Foundation of China(Grant No.42302170)National Postdoctoral Innovative Talent Support Program(Grant No.BX20220062)+3 种基金CNPC Innovation Found(Grant No.2022DQ02-0104)National Science Foundation of Heilongjiang Province of China(Grant No.YQ2023D001)Postdoctoral Science Foundation of Heilongjiang Province of China(Grant No.LBH-Z22091)the Natural Science Foundation of Shandong Province(Grant No.ZR2022YQ30).
文摘Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.
基金Supported by Wang Zhengguo Foundation for Traumatic Medicine“Sequential Medical Research Special Foundation”,No 2024-XGM05.
文摘BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term outcomes.Existing studies have investigated risk factors for POD,but most are limited by single-factor analyses or small sample sizes.This study systematically determines independent risk factors using large-scale data and machine learning techniques and develops a validated nomogram model to support early prediction and management of POD.AIM To investigate POD incidence in elderly patients with HF and the independent risk factors,according to which a nomogram prediction model was developed and validated.METHODS This retrospective study included elderly patients with HF who were surgically treated in Dongying People’sHospital from April 2018 to April 2022. The endpoint event includes POD. They were categorized into themodeling and validation cohorts in a 7:3 ratio by randomization. Both cohorts were further classified into thedelirium and normal (non-delirium) groups according to the presence or absence of the endpoint event. Theincidence of POD was calculated, and logistic multivariate analysis was conducted to determine the independentrisk factors. The calibration curve and the Hosmer-Lemeshow test as well as the net benefit threshold probabilityinterval by the decision curve were utilized to statistically validate the accuracy of the nomogram predictionmodel, developed according to each factor’s influence intensity.RESULTSThis study included 532 elderly patients with HF, with an overall POD incidence of 14.85%. The comparison ofbaseline data with perioperative indicators revealed statistical differences in age (P < 0.001), number of comorbidities(P = 0.042), American Society of Anesthesiologists grading (P = 0.004), preoperative red blood cell(RBC) count (P < 0.001), preoperative albumin (P < 0.001), preoperative hemoglobin (P < 0.001), preoperativeplatelet count (P < 0.001), intraoperative blood loss (P < 0.001), RBC transfusion of ≥ 2 units (P = 0.001), andpostoperative intensive care unit care (P < 0.001) between the delirium and non-delirium groups. The participantswere randomized to a training group (n = 372) and a validation group (n = 160). A score-risk nomogram predictionmodel was developed after screening key POD features using Lasso regression, support vector machine, and therandom forest method. The nomogram showed excellent discriminatory capacity with area under the curve of0.833 [95% confidence interval (CI) interval: 0.774-0.888] in the training group and 0.850 (95%CI: 0.718-0.982) in thevalidation group. Calibration curves demonstrated good agreement between predicted and actual probabilities,and decision curve analysis confirmed clinical net benefits within risk thresholds of 0%-30% and 0%-36%, respectively.The model has strong accuracy and clinical utility for predicting the risk of POD.CONCLUSIONThis study reveals cognitive impairment history, American Society of Anesthesiologists grade of > 2, RBCtransfusion of ≥ 2 units, postoperative intensive care unit care, and preoperative hemoglobin level as independentrisk factors for POD in elderly patients with HF. The developed nomogram model demonstrates excellent accuracyand stability in predicting the risk of POD, which is recommended to be applied in clinical practice to optimizepostoperative management and reduce delirium incidence.
基金supported by the International Collaborative Research Program(fundamental research,2021-2023)funded by Korea Institute of Civil Engineering and Building Technology(KICT).
文摘Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior and its influencing factors are important for the long-term performance assessment of DGRs.We designed multistage mechanical(M)shear tests and thermomechanical(TM)shear tests on three 100 mm-cubic granite specimens,each containing a single inclined sawcut fracture with distinct microroughness of 8-15μm.M test results have shown that the static friction coefficient of the granite fracture decreases in proportion to the increase in the logarithm of the loading rate within the range of 1-15 kPa/s.For the given heating and boundary conditions,thermal loading rate,i.e.,thermal stress increment with heating time,is measured to be around 1 kPa/s in the fractured granite.Thermoshearing can be well predicted by the linear Mohr-Coulomb failure envelope deduced from M shear tests employing a loading rate that is comparable with the thermal loading rate.The granite fractures exhibited two distinct slip patterns during the mechanical shearing,i.e.,stick-slip observed in the smooth fracture and stable sliding in the relatively rough surface.In contrast,the mechanical loading rate(1-15 kPa/s)investigated in this study appears to not influence the slip pattern.Unlike those in M shear tests,thermoshearing in both smooth and relatively rough fractures show stable sliding with a very slow peak velocity of around 0.002μm/s.
基金supported by the National Natural Science Foundation of China(62272049,62236006,62172045)the Key Projects of Beijing Union University(ZKZD202301).
文摘In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods.
基金Supported by the Henan Province Key Research and Development Project(231111211300)the Central Government of Henan Province Guides Local Science and Technology Development Funds(Z20231811005)+2 种基金Henan Province Key Research and Development Project(231111110100)Henan Provincial Outstanding Foreign Scientist Studio(GZS2024006)Henan Provincial Joint Fund for Scientific and Technological Research and Development Plan(Application and Overcoming Technical Barriers)(242103810028)。
文摘The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception.
基金supported by the National Natural Science Foundation of China(Grant Nos.42150204 and 2288101)supported by the China National Postdoctoral Program for Innovative Talents(BX20230045)the China Postdoctoral Science Foundation(2023M730279)。
文摘A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread.
文摘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.
文摘Introduction: Open leg fracture is a diaphyseal or metaphyseal, extra-articular fracture of one or both leg bones, with communication between the fracture site and the external environment. To provide a broader context, studies conducted globally have highlighted the significance of understanding open leg fractures due to their complex management and potential complications. Previous research in Africa and Europe provides comparative data that emphasizes regional differences in fracture types, causes, and treatment outcomes. This study aims to contribute to improving the management of theses fractures in Niger. Materials and Methods: This was a prospective, descriptive study carried out in the Traumatology-Orthopedics Department of the Zinder National Hospital, Niger, from December 8, 2020 to June 8, 2022 (18 months). We included all patients over 15 years of age in whom an open leg fracture was diagnosed and managed. Inclusion criteria focused on patients aged over 15 years with confirmed diagnoses of open leg fractures. Results: Over an 18-month period, the frequency of open leg fractures was 16.28%. There was a predominance of males (85.93% or n = 116). The average age of patients was 31.79 years. Road accidents were the primary circumstance of occurrence (93.33% or n = 126). The fracture line was simple in 74 patients (54.81%) and complex in 61 cases (45.19%). Surgically, the external fixator was used in 78 cases (57.80%). Postoperative follow-up was mostly straightforward. The main complications were infection (4 cases) and delayed consolidation (4 cases). Conclusion: Open leg fractures in adults are frequent at Zinder National Hospital. Public road accidents were the main cause of occurrence. An external fixator osteosynthesis was the most commonly used surgical option. These findings have important implications for healthcare policy, particularly in improving trauma care infrastructure and road safety initiatives in Niger. Future studies should prioritize the development of standardized treatment protocols and investigate the long-term outcomes of different surgical approaches.
文摘This article focuses on the factors influencing fracture nonunion, classification and treatment. The article emphasizes the importance of understanding the influencing factors and mechanisms of fracture healing for developing effective treatment strategies and improving patients’ quality of life. It also points out the challenges of current treatment, such as patient compliance and limitations of treatment methods, and looks at future treatment directions.
基金the National Natural Science Foundation of China(No.52204052)the NationalNatural Science Foundation of China(No.U23B20156)the Sichuan Science and Technology Program(No.2023NSFSC0933).
文摘Shale reservoirs are characterized by numerous geological discontinuities,such as bedding planes,and exhibit pronounced heterogeneity across rock layers separated by these planes.Bedding planes often possess distinct mechanical properties compared to the surrounding rock matrix,particularly in terms of damage and fracture behavior.Consequently,vertical propagation of hydraulic fractures is influenced by both bedding planes and the heterogeneity.In this study,a numerical investigation into the height growth of hydraulic fractures was conducted using the finite element method,incorporating zero-thickness cohesive elements.The analysis explored the effects of bedding planes,toughness contrasts between layers,and variations in in-situ stress across different strata.The results reveal that hydraulic fractures are more likely to propagate along bedding planes instead of traversing them and extending vertically into barrier layers when(1)bedding strength is low,(2)stress contrast between layers is high,and(3)toughness contrast is significant.Furthermore,for a given bedding strength,increased stress contrast or higher toughness contrast between layers elevate hydraulic fracture extension pressure.When a substantial stress difference exists between layers(Lc 0.4),hydraulic=fractures preferentially propagate along bedding planes.Conversely,as bedding strength increases,the propagation distance along bedding planes decreases,accompanied by an amplified horizontal compressive stress field.Notably,when the stress difference is sufficiently small(SD a phenomenon termed“stress rolling”emerges,wherein<-0.2),hydraulic fractures deviate from vertical growth and instead extend along a near-horizontal trajectory.
基金This study was supported by the Foundation of National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields(2023-015).
文摘Hydraulic fracturing is a crucial technique for efficient development of coal reservoirs.Coal rocks typically contain a high density of natural fractures,which serve as conduits for fracturing fluid.Upon injection,the fluid infiltrates these natural fractures and leaks out,resulting in complex fracture morphology.The prediction of hydraulic fracture network propagation for coal reservoirs has important practical significance for evaluating hydraulic fracturing.This study proposes a novel inversion method for predicting fracture networks in coal reservoirs,explicitly considering the distribution of natural fractures.The method incorporates three distinct natural fracture opening modes and employs a fractal probability function to constrain fracture propagationmorphology.Based on thismethod,the study compares hydraulic fracture networkmorphologies in coal reservoirs with andwithout the presence of natural fractures.Theresults showthatwhile both reservoir types exhibitmulti-branch fracture networks,reservoirs containing natural fractures demonstrate greater branching and a larger stimulated reservoir volume(SRV).Additionally,the study employs a fractal dimension calculation method to quantitatively describe the geometric distribution characteristics of fractures.The analysis reveals that the geometry and distribution of natural fractures,as well as reservoir geological parameters,significantly influence the fracture networkmorphology and fractal dimension.The contact angle between natural and hydraulic fractures affects propagation direction;specifically,when the contact angle isπ/2,the fractal dimension of the hydraulic fracture network is maximized.Moreover,smaller lengths and spacings of natural fracture led to higher fractal dimensions,which can significantly increase the SRV.The proposed method offers an effective tool for evaluating the hydraulic fracturing of coal reservoirs.
文摘Background and Objectives: The distal radius fracture (DRF) is a major public health problem in northern countries. Its frequency is constantly increasing. The locked anterior plate with its well-established biomechanical properties, offers a reliable alternative. The aim of this study was to evaluate the radiological, the functional results and to determine the factors of poor postoperative prognosis of DRF treated with Newclip radial plates®. Methodology: This prospective cohort study evaluates the radiological and functional outcames of displaced radius fractures (DRFs) in patients ≥50 years old treated with Newclip® (locked anterior plates) at the Basse-Terre Hospital in Guadeloupe from 2022 to 2024. The patients were categorized into those with epiphyseal involvement (E1 - E4) and without epiphyseal involvement (E0) based on Laulan’s MEU classification. Radiological parameters (distal radio-ulnar index (DRUI), radial inclination frant view (IRF), radial inclination sagittal view (IRS) were assessed pre and post-operatively. Functional recovery was evaluated at 12 months using the QuickDash questionnaire. Results: Falls were the most common cause of fracture. Post-operatively, SRI was the least restored parameter. Poor prognostic factor for SRI improvement included posterior commimution and unstable fractures. Factors associated with higher QuickDash scores included unstable factures, unrestored DRUI, low plate position, metaphyseal features, and ulnar features. Conclusion: The anterior locking plate osteosynthesis is reliable treatment option with excellent functional outcomes.
文摘Periprosthetic fracture of femur is a common and complex complication after joint replacement. With the increase of operation volume, its incidence is increasing year by year. The treatment of this fracture is affected by many factors, including fracture type, prosthesis stability, patient age and comorbidities, and individualized treatment strategy is needed. In recent years, the internal fixation technology and prosthetic revision technology have made significant progress in surgical treatment, such as locking steel plate, titanium cable and bridge combined internal fixation system and other new technologies have effectively improved the treatment effect. In addition, the application of new materials and 3D printing technology, as well as the optimization of multidisciplinary cooperation mode, also provide new ideas for the treatment of complex fractures. However, there are still some problems such as inaccurate diagnosis, difficult choice of treatment options and high incidence of postoperative complications. In the future, technological innovation, the introduction of artificial intelligence and big data, and the further development of personalized treatment will bring more possibilities to improve the prognosis and quality of life of patients. This study summarizes the relevant research results and prospects the future development direction, providing references for clinical practice and subsequent research.
文摘According to World Health Organization,one in six people will be older than 60 by 2030.The rising life expectancy is anticipated to contribute to a subsequent increase of geriatric fractures worldwide.Osteosarcopenia,which is the coexistence of osteoporosis and sarcopenia,greatly affects older people.Recent studies have tried to identify the prevalence of osteosarcopenia in older populations as well as its correlation with fragility fractures such as hip fractures.The latter pose a major burden on both health loss and costs worldwide.Increasing amount of evidence suggests that osteosarcopenia in patients with hip fractures contributes to higher rates of mortality and complications.At the same time,research focuses on the molecular basis of the interplay between osteoporosis and sarcopenia by utilizing genomic or proteomic approaches.These promising studies could reveal potential preventive or diagnostic biomarkers to optimize the management of osteosarcopenia in hip fractures patients.The fact that bones and muscle can also function as endocrine organs further highlights the complex relationship between osteoporosis and sarcopenia,underscoring the need for a better understanding of the role of myokines and osteokines in osteosarcopenia.Finally,the impact of osteosarcopenia on pain management and rehabilitation after hip fracture surgery,requires further assessment.
基金supported by the National Natural Science Foundation of China(Grant No.12302500)the National Key Research and Development Program of China(Grant No.2020YFA0710503)Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(Grant No.GBZ20230022).
文摘Controllable shock wave fracturing is an innovative engineering technique used for shale reservoir fracturing and reformation.Understanding the anisotropic fracture mechanism of shale under impact loading is vital for optimizing shock wave fracturing equipment and enhancing shale oil production.In this study,using the well-known notched semi-circular bend(NSCB)sample and the novel double-edge notched flattened Brazilian disc(DNFBD)sample combined with a split Hopkinson pressure bar(SHPB),various dynamic anisotropic fracture properties of Lushan shale,including failure characteristics,fracture toughness,energy dissipation and crack propagation velocity,are comprehensively compared and discussed under mode Ⅰ and mode Ⅱ fracture scenarios.First,using a newly modified fracture criterion considering the strength anisotropy of shale,the DNFBD specimen is predicted to be a robust method for true mode Ⅱ fracture of anisotropic shale rocks.Our experimental results show that the dynamic mode Ⅱ fracture of shale induces a rougher and more complex fracture morphology and performs a higher fracture toughness or fracture energy compared to dynamic mode Ⅰ fracture.The minimal fracture toughness or fracture energy occurs in the Short-transverse orientation,while the maximal ones occur in the Divider orientation.In addition,it is interesting to find that the mode Ⅱ fracture toughness anisotropy index decreases more slowly than that in the mode Ⅰ fracture scenario.These results provide significant insights for understanding the different dynamic fracture mechanisms of anisotropic shale rocks under impact loading and have some beneficial implications for the controllable shock wave fracturing technique.