A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves...A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves precise adjustment of the network structure by constructing a preliminary random network model and introducing small-world network characteristics and combines L1 norm minimization regularization techniques to control model complexity and optimize the inference process of variable dependencies.In the experiment of game network reconstruction,when the success rate of the L1 norm minimization model’s existence connection reconstruction reaches 100%,the minimum data required is about 40%,while the minimum data required for a sparse Bayesian learning network is about 45%.In terms of operational efficiency,the running time for minimizing the L1 normis basically maintained at 1.0 s,while the success rate of connection reconstruction increases significantly with an increase in data volume,reaching a maximum of 13.2 s.Meanwhile,in the case of a signal-to-noise ratio of 10 dB,the L1 model achieves a 100% success rate in the reconstruction of existing connections,while the sparse Bayesian network had the highest success rate of 90% in the reconstruction of non-existent connections.In the analysis of actual cases,the maximum lift and drop track of the research method is 0.08 m.The mean square error is 5.74 cm^(2).The results indicate that this norm minimization-based method has good performance in data efficiency and model stability,effectively reducing the impact of outliers on the reconstruction results to more accurately reflect the actual situation.展开更多
Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transit...Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation.展开更多
In task offloading,the movement of vehicles causes the switching of connected RSUs and servers,which may lead to task offloading failure or high service delay.In this paper,we analyze the impact of vehicle movements o...In task offloading,the movement of vehicles causes the switching of connected RSUs and servers,which may lead to task offloading failure or high service delay.In this paper,we analyze the impact of vehicle movements on task offloading and reveal that data preparation time for task execution can be minimized via forward-looking scheduling.Then,a Bi-LSTM-based model is proposed to predict the trajectories of vehicles.The service area is divided into several equal-sized grids.If the actual position of the vehicle and the predicted position by the model belong to the same grid,the prediction is considered correct,thereby reducing the difficulty of vehicle trajectory prediction.Moreover,we propose a scheduling strategy for delay optimization based on the vehicle trajectory prediction.Considering the inevitable prediction error,we take some edge servers around the predicted area as candidate execution servers and the data required for task execution are backed up to these candidate servers,thereby reducing the impact of prediction deviations on task offloading and converting the modest increase of resource overheads into delay reduction in task offloading.Simulation results show that,compared with other classical schemes,the proposed strategy has lower average task offloading delays.展开更多
Recently,the Fog-Radio Access Network(F-RAN)has gained considerable attention,because of its flexible architecture that allows rapid response to user requirements.In this paper,computational offloading in F-RAN is con...Recently,the Fog-Radio Access Network(F-RAN)has gained considerable attention,because of its flexible architecture that allows rapid response to user requirements.In this paper,computational offloading in F-RAN is considered,where multiple User Equipments(UEs)offload their computational tasks to the F-RAN through fog nodes.Each UE can select one of the fog nodes to offload its task,and each fog node may serve multiple UEs.The tasks are computed by the fog nodes or further offloaded to the cloud via a capacity-limited fronhaul link.In order to compute all UEs'tasks quickly,joint optimization of UE-Fog association,radio and computation resources of F-RAN is proposed to minimize the maximum latency of all UEs.This min-max problem is formulated as a Mixed Integer Nonlinear Program(MINP).To tackle it,first,MINP is reformulated as a continuous optimization problem,and then the Majorization Minimization(MM)method is used to find a solution.The MM approach that we develop is unconventional in that each MM subproblem is solved inexactly with the same provable convergence guarantee as the exact MM,thereby reducing the complexity of MM iteration.In addition,a cooperative offloading model is considered,where the fog nodes compress-and-forward their received signals to the cloud.Under this model,a similar min-max latency optimization problem is formulated and tackled by the inexact MM.Simulation results show that the proposed algorithms outperform some offloading strategies,and that the cooperative offloading can exploit transmission diversity better than noncooperative offloading to achieve better latency performance.展开更多
We propose the Dantzig selector based on the l_(1-q)(1<q≤2)minimization model for the sparse signal recovery.First,we discuss some properties of l_(1-q)minimization model and give some useful inequalities.Then,we ...We propose the Dantzig selector based on the l_(1-q)(1<q≤2)minimization model for the sparse signal recovery.First,we discuss some properties of l_(1-q)minimization model and give some useful inequalities.Then,we give a sufficient condition based on the restricted isometry property for the stable recovery of signals.The l_(1-2)minimization model of Yin-Lou-He is extended to the l_(1-q)minimization model.展开更多
Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transfo...Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data： namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm.展开更多
With the entropy generation minimization （EGM） method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat tr...With the entropy generation minimization （EGM） method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat transfer caused by finite temperature differences, the heat leak between external heat reservoirs and the internal dissipation of working fluids. EGM is taken as an objective function for the optimization. The objective function and design parameters are obtained. Optimal performance curves are presented by thermal and electronic parameters. Effects of these parameters on general and optimal performances are investigated. Results are helpful in determining optimal design conditions in real thermoelectric refrigeration systems.展开更多
Systems using numerous cameras are emerging in many fields due to their ease of production and reduced cost, and one of the fields where they are expected to be used more actively in the near future is in image-based ...Systems using numerous cameras are emerging in many fields due to their ease of production and reduced cost, and one of the fields where they are expected to be used more actively in the near future is in image-based rendering （IBR）. Color correction between views is necessary to use multi-view systems in IBR to make audiences feel comfortable when views are switched or when a free viewpoint video is displayed. Color correction usually involves two steps： the first is to adjust camera parameters such as gain, brightness, and aperture before capture, and the second is to modify captured videos through image processing. This paper deals with the latter, which does not need a color pattern board. The proposed method uses scale invariant feature transform （SIFT） to detect correspondences, treats RGB channels independently, calculates lookup tables with an energy-minimization approach, and corrects captured video with these tables. The experimental results reveal that this approach works well.展开更多
BACKGROUND Robotic assistance is increasingly used for donor and recipient hepatectomy in liver transplantation,yet existing evidence is fragmented and variably indirect.AIM To evaluate clinical outcomes,surgical perf...BACKGROUND Robotic assistance is increasingly used for donor and recipient hepatectomy in liver transplantation,yet existing evidence is fragmented and variably indirect.AIM To evaluate clinical outcomes,surgical performance,and economic effects of robotic-assisted donor and recipient hepatectomy in the transplant pathway.METHODS Following Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 and a priori registration,systematic reviews were included with or without meta-analysis.Four databases were searched through July 2025.Methodological quality was appraised with a measurement tool to assess systematic reviews(AMSTAR 2),and certainty was graded with grading of recommendations assessment,development and evaluation(GRADE).Evidence overlap was calculated via a citation-matrix-based corrected covered area(CCA).Effect sizes were prespecified as risk ratios(RR)for dichotomous outcomes and mean differences for continuous outcomes.RESULTS Five reviews met the inclusion criteria,four with meta-analyses and one consensus review used only for context.Donor(direct)findings were more favorable for robotics in terms of estimated blood loss(≈-117 mL)and length of stay(≈-0.6 days),although with longer operative time(≈+105 minutes).Absolute risks for donor complications were not estimable from ratio-only data.Recipient(indirect)meta-analysis indicated robotics to be favorable in terms of conversion(RR≈0.41)and severe morbidity(RR≈0.81),with a trend toward lower overall morbidity(RR≈0.92)and no difference in 30-day mortality.Differences in length of stay and operative time were small and heterogeneous.Economic evidence(indirect,network meta-analysis)suggested higher procedural costs for robotic vs laparoscopic intervention,but lower hospitalization costs vs open intervention,with laparoscopy the least expensive overall.AMSTAR 2 ratings were moderate-to-high across the reviews,GRADE certainty was low for key donor continuous outcomes,and low-to-moderate for recipient and economic outcomes.Overlap was slight(graded-corpus CCA=0.0%;including a contextual non-transplant review increased CCA to≈1.25%).CONCLUSION Robotic donor hepatectomy confers perioperative advantages at the cost of longer operative time.Recipient and economic findings are indirect and considered hypothesis-generating.Transplant-specific,prospective comparisons using a minimum standardized dataset and uniform outcome definitions are needed to resolve remaining uncertainties and to clarify the cost-utility correlation.展开更多
Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves ...Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves targeting superficial tumors in patients with macronodular cirrhosis and an irregular liver surface.In a minimally invasive setting,the lack of tactile feedback on the hepatic surface makes detecting subcapsular HCC with ultrasound alone challenging.ICG fusion images can mimic the tactile feedback of the hand and act as an ultrasound booster.ICG fluorescence can be used to evaluate tumor residues after minimally invasive thermal ablation.ICG fluorescence imaging can also be used to identify the grade of HCC early on and evaluate the microinvasive component.展开更多
BACKGROUND Living donor kidney transplantation is the optimal method of long-term renal replacement therapy.Minimally invasive donor nephrectomy techniques,such as robot-assisted(RALDN)and hand-assisted(HALDN)laparosc...BACKGROUND Living donor kidney transplantation is the optimal method of long-term renal replacement therapy.Minimally invasive donor nephrectomy techniques,such as robot-assisted(RALDN)and hand-assisted(HALDN)laparoscopic procedures,are well-established in high-income countries and are being increasingly adopted worldwide.Nevertheless,no studies have reported surgical outcomes of RALDN donor nephrectomy from a United Kingdom center to date.AIM To compare surgical outcomes between RALDN and HALDN laparoscopic donor nephrectomy in a United Kingdom high-volume living kidney donor transplant program.METHODS A case-control matching analysis was performed based on the following parameters:Sex,age,body mass index,procedure laterality,number of renal arteries,and previous abdominal surgeries.Key surgical outcomes,including primary warm ischemia time,operative duration,and post-operative recovery,were evaluated.RESULTS In this cohort of 140 living donors(70 RALDN vs 70 HALDN),donor and recipient outcomes were equivalent across key metrics:Pain scores,overall complication rates,readmissions,reoperations,and creatinine levels at 30 days and 1 year.Recipient long-term renal function did not differ between groups.Operative time for RALDN decreased significantly over the study period,indicating progressive improvement along the learning curve.Although RALDN was associated with a modestly longer mean warm ischaemia time(3.53 minutes vs 2.76 minutes,P<0.001)and extended hospital stay(4.21 days vs 3.17 days,P<0.001),these did not translate into any disadvantage in clinical outcomes.CONCLUSION In this first United Kingdom comparative cohort,RALDN demonstrated excellent safety and efficacy,even in the early phase of our programme,matching the outcomes of the well-established,gold-standard HALDN approach.Moreover,the pronounced learning-curve trajectory suggests considerable potential for further improvements in robotic surgical outcomes as the programme matures.展开更多
This article provides an overview of an eleven step solid waste analysis and minimization process that is based on the six sigma approach to problem solving that may be applied at a wide variety of organizations. The ...This article provides an overview of an eleven step solid waste analysis and minimization process that is based on the six sigma approach to problem solving that may be applied at a wide variety of organizations. The six sigma approach provides a holistic process that focuses on minimizing defects, in this case, eliminating waste disposed at landfills. As many organizations are moving towards ＂zero landfill＂ facilities, such a process is needed to aid in achieving these goals. The eleven step processes provides details on establishing goals, creating process flowcharts, conducting waste sorts, data collection, establishing baseline data, identifying improvement opportunities, cost justification, executing improvement plans and validating results. The article also includes a case study that applies that eleven step process. The goal of the article is to provide the audience with a structured process to evaluate and minimize solid waste generation based on cost justified improvement opportunities.展开更多
BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly dev...BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly developed Pringle taping method guided by liver surface in MISRLR.METHODS We retrospectively reviewed 72 cases of MISRLR performed by a single surgeon at two centers from August 2015 to July 2024.Beginning in October 2019,a liver surface-guided encirclement of hepatoduodenal ligament(LSEH)was used for repeat Pringle taping.Perioperative outcomes including Pringle taping success,operative time,blood loss,conversion rate,morbidity,and mortality were assessed.RESULTS Laparoscopic and robotic approaches were used in 63 patients and 9 patients,respectively.The median operative time,blood loss,and hospital stay were 331.5 minutes,70 mL,and 8 days,respectively.Open conversion occurred in two cases(2.8%)due to severe adhesions and right renal vein injury.Clavien-Dindo grade≥III complications occurred in 5.6%of cases with no mortality.Anti-adhesion barriers were used in 54 patients(75.0%).LSEH was attempted in 57 cases,improving Pringle taping success from 33.0%to 91.4%(P<0.001).LSEH succeeded in all patients with prior open liver resection(n=11).Among 6 patients in whom LSEH failed,3 patients(50.0%)had undergone a third liver resection,and 1 patient had a history of distal gastrectomy with choledochoduodenostomy.CONCLUSION The newly developed LSEH technique for Pringle taping in MISRLR was feasible,enhancing safety and reproducibility even in patients with a history of open liver resection.展开更多
Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminog...Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminogen activator may come into contact with brain tissue.Therefore,a thorough assessment of its safety is required.In this study,we established a mouse model of intracerebral hemorrhage induced by type VII collagenase.We observed that the administration of recombinant tissue plasminogen activator without hematoma aspiration significantly improved the neurological function of mice with intracerebral hemorrhage,reduced pathological damage,and lowered the levels of apoptosis and autophagy in the tissue surrounding the hematoma.In an in vitro model of intracerebral hemorrhage using primary cortical neurons induced by hemin,the administration of recombinant tissue plasminogen activator suppressed neuronal apoptosis,autophagy,and endoplasmic reticulum stress.Transcriptome sequencing analysis revealed that recombinant tissue plasminogen activator upregulated the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway in neurons.Moreover,the phosphoinositide 3-kinase inhibitor LY294002 abrogated the neuroprotective effects of recombinant tissue plasminogen activator in inhibiting excessive apoptosis,autophagy,and endoplasmic reticulum stress.Furthermore,to specify the domain of recombinant tissue plasminogen activator responsible for its neuroprotective effects,various inhibitors were used to target distinct domains.It has been revealed that the epidermal growth factor receptor inhibitor AG-1478 reversed the effect of recombinant tissue plasminogen activator on the phosphoinositide 3-kinase/RAC-alpha serine/threonineprotein kinase/mammalian target of rapamycin pathway.These findings suggest that recombinant tissue plasminogen activator exerts a direct neuroprotective effect on neurons following intracerebral hemorrhage,possibly through activation of the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway.展开更多
背景:腰椎退行性疾病是一种中老年人常见疾病,临床表现主要为腰背部疼痛和下肢功能障碍。传统上使用腰椎融合联合双侧椎弓根螺钉固定进行外科干预,但存在创伤大、并发症多等问题。而腰椎融合联合单侧椎弓根螺钉固定是一种新兴的微创治...背景:腰椎退行性疾病是一种中老年人常见疾病,临床表现主要为腰背部疼痛和下肢功能障碍。传统上使用腰椎融合联合双侧椎弓根螺钉固定进行外科干预,但存在创伤大、并发症多等问题。而腰椎融合联合单侧椎弓根螺钉固定是一种新兴的微创治疗方式,具有较小的创伤和较低的并发症风险,已逐渐成为腰椎退行性疾病治疗的新选择。目的:探讨腰椎融合联合单侧椎弓根螺钉固定治疗腰椎退行性疾病的效果及优势。方法:通过检索中国知网和PubMed数据库2010年1月至2025年1月发表的相关文献,总结腰椎融合联合单侧椎弓根螺钉固定的临床研究及生物力学特点,以“腰椎融合术,单侧固定,双侧固定,生物力学,腰椎退行性疾病”为中文检索词,以“lumbar fusion,unilateral fixation,bilateral fixation,biomechanics,degenerative disease of the lumbar spine”为英文检索词,最终纳入70篇文献进行综述。结果与结论:①腰椎融合联合单侧椎弓根螺钉固定能有效减少手术创伤和术中失血量,提供与双侧椎弓根螺钉固定相似的生物力学稳定性,并降低邻近节段退变的风险;②单侧椎弓根螺钉固定在单节段及双节段腰椎退行性疾病治疗中已获得广泛认可,但在多节段腰椎退行性疾病中的应用效果仍需进一步研究;③腰椎融合联合单侧椎弓根螺钉固定为腰椎退行性疾病治疗提供了微创、安全的选择,未来需要更多高质量的研究验证其在复杂病例中的应用和长期疗效,进一步优化临床应用。展开更多
背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探...背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探究材料种类及厚度对全瓷修复体美学性能的影响。方法:选取各类可切削陶瓷中6种代表性的材料(常规氧化锆ZR-ST、树脂基陶瓷RC、高透氧化锆ZR-TT、白榴石增强玻璃陶瓷LE、二硅酸锂玻璃陶瓷LD及长石质瓷FP),每种材料分别制备成0.8,1.0,1.5 mm厚的10.0 mm×12.5 mm长方体陶瓷试件,进行对应的表面处理后与树脂试件(代表基牙)粘接制成陶瓷-树脂复合体试件,测算粘接前后的CIEL^(*)a^(*)b^(*)、色差值ΔE及透光率值。结果与结论:①当基牙厚度未达到无限光学厚度时,陶瓷材料的种类和厚度共同影响修复体的颜色和透光率值。当陶瓷试件厚度不超过1.0 mm时,与树脂片粘接后的颜色普遍向蓝红趋近;当陶瓷试件厚度为1.5 mm时,与树脂片粘接后的颜色普遍向蓝绿趋近,提示在全瓷修复体比色时可通过颜色预补偿优化美学匹配。②除厚度1.5 mm ZR-ST陶瓷试件外,粘接后各组陶瓷试件与树脂片之间的色差值ΔE均低于5,0.8 mm ZR-ST陶瓷试件与树脂片之间的色差值ΔE接近3,1.0 mm ZR-TT陶瓷试件与树脂片之间的色差值ΔE小于3,提示在微创修复过程中,若患牙透光率不高且美学修复空间不足、对材料强度要求高时,ZR-TT和ZR-ST陶瓷可能是潜在的选择。③陶瓷试件的透光率值在粘接后降低,并随陶瓷厚度的增加显著降低。RC陶瓷试件的透光率值高,粘接后与树脂片之间的色差值ΔE接近3,光学性能出色。展开更多
基金supported by the Scientific and Technological Developing Scheme of Jilin Province,China(No.20240101371JC)the National Natural Science Foundation of China(No.62107008).
文摘A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves precise adjustment of the network structure by constructing a preliminary random network model and introducing small-world network characteristics and combines L1 norm minimization regularization techniques to control model complexity and optimize the inference process of variable dependencies.In the experiment of game network reconstruction,when the success rate of the L1 norm minimization model’s existence connection reconstruction reaches 100%,the minimum data required is about 40%,while the minimum data required for a sparse Bayesian learning network is about 45%.In terms of operational efficiency,the running time for minimizing the L1 normis basically maintained at 1.0 s,while the success rate of connection reconstruction increases significantly with an increase in data volume,reaching a maximum of 13.2 s.Meanwhile,in the case of a signal-to-noise ratio of 10 dB,the L1 model achieves a 100% success rate in the reconstruction of existing connections,while the sparse Bayesian network had the highest success rate of 90% in the reconstruction of non-existent connections.In the analysis of actual cases,the maximum lift and drop track of the research method is 0.08 m.The mean square error is 5.74 cm^(2).The results indicate that this norm minimization-based method has good performance in data efficiency and model stability,effectively reducing the impact of outliers on the reconstruction results to more accurately reflect the actual situation.
基金supported by The Shenzhen Educational Research Funding(zdzb2014)The Shenzhen Science and Technology Innovation Commission(202307313000096)+4 种基金The Social Science Foundation from the China's Ministry of Education(23YJA880093)The Post-Doctoral Fellowship(2022M711174)The National Center for Mental Health(Z014)BC is supported by the Chaires de recherche Rennes Métropole(23C 0909)SM is supported by the National Insti-tutes of Health(R01AG72445).
文摘Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation.
基金supported in part by the National Science Foundation of China(Grant No.62172450)the Key R&D Plan of Hunan Province(Grant No.2022GK2008)the Nature Science Foundation of Hunan Province(Grant No.2020JJ4756)。
文摘In task offloading,the movement of vehicles causes the switching of connected RSUs and servers,which may lead to task offloading failure or high service delay.In this paper,we analyze the impact of vehicle movements on task offloading and reveal that data preparation time for task execution can be minimized via forward-looking scheduling.Then,a Bi-LSTM-based model is proposed to predict the trajectories of vehicles.The service area is divided into several equal-sized grids.If the actual position of the vehicle and the predicted position by the model belong to the same grid,the prediction is considered correct,thereby reducing the difficulty of vehicle trajectory prediction.Moreover,we propose a scheduling strategy for delay optimization based on the vehicle trajectory prediction.Considering the inevitable prediction error,we take some edge servers around the predicted area as candidate execution servers and the data required for task execution are backed up to these candidate servers,thereby reducing the impact of prediction deviations on task offloading and converting the modest increase of resource overheads into delay reduction in task offloading.Simulation results show that,compared with other classical schemes,the proposed strategy has lower average task offloading delays.
基金supported in part by the Natural Science Foundation of China (62171110,U19B2028 and U20B2070)。
文摘Recently,the Fog-Radio Access Network(F-RAN)has gained considerable attention,because of its flexible architecture that allows rapid response to user requirements.In this paper,computational offloading in F-RAN is considered,where multiple User Equipments(UEs)offload their computational tasks to the F-RAN through fog nodes.Each UE can select one of the fog nodes to offload its task,and each fog node may serve multiple UEs.The tasks are computed by the fog nodes or further offloaded to the cloud via a capacity-limited fronhaul link.In order to compute all UEs'tasks quickly,joint optimization of UE-Fog association,radio and computation resources of F-RAN is proposed to minimize the maximum latency of all UEs.This min-max problem is formulated as a Mixed Integer Nonlinear Program(MINP).To tackle it,first,MINP is reformulated as a continuous optimization problem,and then the Majorization Minimization(MM)method is used to find a solution.The MM approach that we develop is unconventional in that each MM subproblem is solved inexactly with the same provable convergence guarantee as the exact MM,thereby reducing the complexity of MM iteration.In addition,a cooperative offloading model is considered,where the fog nodes compress-and-forward their received signals to the cloud.Under this model,a similar min-max latency optimization problem is formulated and tackled by the inexact MM.Simulation results show that the proposed algorithms outperform some offloading strategies,and that the cooperative offloading can exploit transmission diversity better than noncooperative offloading to achieve better latency performance.
基金supported by the National Natural Science Foundation of China“Variable exponential function spaces on variable anisotropic Euclidean spaces and their applications”(12261083),“Harmonic analysis on affine symmetric spaces”(12161083).
文摘We propose the Dantzig selector based on the l_(1-q)(1<q≤2)minimization model for the sparse signal recovery.First,we discuss some properties of l_(1-q)minimization model and give some useful inequalities.Then,we give a sufficient condition based on the restricted isometry property for the stable recovery of signals.The l_(1-2)minimization model of Yin-Lou-He is extended to the l_(1-q)minimization model.
基金supported by the National Natural Science Foundation of China (Grant No.41074133)
文摘Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data： namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm.
文摘With the entropy generation minimization （EGM） method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat transfer caused by finite temperature differences, the heat leak between external heat reservoirs and the internal dissipation of working fluids. EGM is taken as an objective function for the optimization. The objective function and design parameters are obtained. Optimal performance curves are presented by thermal and electronic parameters. Effects of these parameters on general and optimal performances are investigated. Results are helpful in determining optimal design conditions in real thermoelectric refrigeration systems.
文摘Systems using numerous cameras are emerging in many fields due to their ease of production and reduced cost, and one of the fields where they are expected to be used more actively in the near future is in image-based rendering （IBR）. Color correction between views is necessary to use multi-view systems in IBR to make audiences feel comfortable when views are switched or when a free viewpoint video is displayed. Color correction usually involves two steps： the first is to adjust camera parameters such as gain, brightness, and aperture before capture, and the second is to modify captured videos through image processing. This paper deals with the latter, which does not need a color pattern board. The proposed method uses scale invariant feature transform （SIFT） to detect correspondences, treats RGB channels independently, calculates lookup tables with an energy-minimization approach, and corrects captured video with these tables. The experimental results reveal that this approach works well.
文摘BACKGROUND Robotic assistance is increasingly used for donor and recipient hepatectomy in liver transplantation,yet existing evidence is fragmented and variably indirect.AIM To evaluate clinical outcomes,surgical performance,and economic effects of robotic-assisted donor and recipient hepatectomy in the transplant pathway.METHODS Following Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 and a priori registration,systematic reviews were included with or without meta-analysis.Four databases were searched through July 2025.Methodological quality was appraised with a measurement tool to assess systematic reviews(AMSTAR 2),and certainty was graded with grading of recommendations assessment,development and evaluation(GRADE).Evidence overlap was calculated via a citation-matrix-based corrected covered area(CCA).Effect sizes were prespecified as risk ratios(RR)for dichotomous outcomes and mean differences for continuous outcomes.RESULTS Five reviews met the inclusion criteria,four with meta-analyses and one consensus review used only for context.Donor(direct)findings were more favorable for robotics in terms of estimated blood loss(≈-117 mL)and length of stay(≈-0.6 days),although with longer operative time(≈+105 minutes).Absolute risks for donor complications were not estimable from ratio-only data.Recipient(indirect)meta-analysis indicated robotics to be favorable in terms of conversion(RR≈0.41)and severe morbidity(RR≈0.81),with a trend toward lower overall morbidity(RR≈0.92)and no difference in 30-day mortality.Differences in length of stay and operative time were small and heterogeneous.Economic evidence(indirect,network meta-analysis)suggested higher procedural costs for robotic vs laparoscopic intervention,but lower hospitalization costs vs open intervention,with laparoscopy the least expensive overall.AMSTAR 2 ratings were moderate-to-high across the reviews,GRADE certainty was low for key donor continuous outcomes,and low-to-moderate for recipient and economic outcomes.Overlap was slight(graded-corpus CCA=0.0%;including a contextual non-transplant review increased CCA to≈1.25%).CONCLUSION Robotic donor hepatectomy confers perioperative advantages at the cost of longer operative time.Recipient and economic findings are indirect and considered hypothesis-generating.Transplant-specific,prospective comparisons using a minimum standardized dataset and uniform outcome definitions are needed to resolve remaining uncertainties and to clarify the cost-utility correlation.
文摘Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves targeting superficial tumors in patients with macronodular cirrhosis and an irregular liver surface.In a minimally invasive setting,the lack of tactile feedback on the hepatic surface makes detecting subcapsular HCC with ultrasound alone challenging.ICG fusion images can mimic the tactile feedback of the hand and act as an ultrasound booster.ICG fluorescence can be used to evaluate tumor residues after minimally invasive thermal ablation.ICG fluorescence imaging can also be used to identify the grade of HCC early on and evaluate the microinvasive component.
文摘BACKGROUND Living donor kidney transplantation is the optimal method of long-term renal replacement therapy.Minimally invasive donor nephrectomy techniques,such as robot-assisted(RALDN)and hand-assisted(HALDN)laparoscopic procedures,are well-established in high-income countries and are being increasingly adopted worldwide.Nevertheless,no studies have reported surgical outcomes of RALDN donor nephrectomy from a United Kingdom center to date.AIM To compare surgical outcomes between RALDN and HALDN laparoscopic donor nephrectomy in a United Kingdom high-volume living kidney donor transplant program.METHODS A case-control matching analysis was performed based on the following parameters:Sex,age,body mass index,procedure laterality,number of renal arteries,and previous abdominal surgeries.Key surgical outcomes,including primary warm ischemia time,operative duration,and post-operative recovery,were evaluated.RESULTS In this cohort of 140 living donors(70 RALDN vs 70 HALDN),donor and recipient outcomes were equivalent across key metrics:Pain scores,overall complication rates,readmissions,reoperations,and creatinine levels at 30 days and 1 year.Recipient long-term renal function did not differ between groups.Operative time for RALDN decreased significantly over the study period,indicating progressive improvement along the learning curve.Although RALDN was associated with a modestly longer mean warm ischaemia time(3.53 minutes vs 2.76 minutes,P<0.001)and extended hospital stay(4.21 days vs 3.17 days,P<0.001),these did not translate into any disadvantage in clinical outcomes.CONCLUSION In this first United Kingdom comparative cohort,RALDN demonstrated excellent safety and efficacy,even in the early phase of our programme,matching the outcomes of the well-established,gold-standard HALDN approach.Moreover,the pronounced learning-curve trajectory suggests considerable potential for further improvements in robotic surgical outcomes as the programme matures.
文摘This article provides an overview of an eleven step solid waste analysis and minimization process that is based on the six sigma approach to problem solving that may be applied at a wide variety of organizations. The six sigma approach provides a holistic process that focuses on minimizing defects, in this case, eliminating waste disposed at landfills. As many organizations are moving towards ＂zero landfill＂ facilities, such a process is needed to aid in achieving these goals. The eleven step processes provides details on establishing goals, creating process flowcharts, conducting waste sorts, data collection, establishing baseline data, identifying improvement opportunities, cost justification, executing improvement plans and validating results. The article also includes a case study that applies that eleven step process. The goal of the article is to provide the audience with a structured process to evaluate and minimize solid waste generation based on cost justified improvement opportunities.
文摘BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly developed Pringle taping method guided by liver surface in MISRLR.METHODS We retrospectively reviewed 72 cases of MISRLR performed by a single surgeon at two centers from August 2015 to July 2024.Beginning in October 2019,a liver surface-guided encirclement of hepatoduodenal ligament(LSEH)was used for repeat Pringle taping.Perioperative outcomes including Pringle taping success,operative time,blood loss,conversion rate,morbidity,and mortality were assessed.RESULTS Laparoscopic and robotic approaches were used in 63 patients and 9 patients,respectively.The median operative time,blood loss,and hospital stay were 331.5 minutes,70 mL,and 8 days,respectively.Open conversion occurred in two cases(2.8%)due to severe adhesions and right renal vein injury.Clavien-Dindo grade≥III complications occurred in 5.6%of cases with no mortality.Anti-adhesion barriers were used in 54 patients(75.0%).LSEH was attempted in 57 cases,improving Pringle taping success from 33.0%to 91.4%(P<0.001).LSEH succeeded in all patients with prior open liver resection(n=11).Among 6 patients in whom LSEH failed,3 patients(50.0%)had undergone a third liver resection,and 1 patient had a history of distal gastrectomy with choledochoduodenostomy.CONCLUSION The newly developed LSEH technique for Pringle taping in MISRLR was feasible,enhancing safety and reproducibility even in patients with a history of open liver resection.
基金supported by the National Natural Science Foundation of China,Nos.92148206,82071330(both to ZT)a grant from the Major Program of Hubei Province,No.2023BAA005(to ZT)+1 种基金a grant from the Key Research and Discovery Program of Hubei Province,No.2021BCA109(to ZT)the Research Foundation of Tongji Hospital,No.2022B37(to PZ)。
文摘Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminogen activator may come into contact with brain tissue.Therefore,a thorough assessment of its safety is required.In this study,we established a mouse model of intracerebral hemorrhage induced by type VII collagenase.We observed that the administration of recombinant tissue plasminogen activator without hematoma aspiration significantly improved the neurological function of mice with intracerebral hemorrhage,reduced pathological damage,and lowered the levels of apoptosis and autophagy in the tissue surrounding the hematoma.In an in vitro model of intracerebral hemorrhage using primary cortical neurons induced by hemin,the administration of recombinant tissue plasminogen activator suppressed neuronal apoptosis,autophagy,and endoplasmic reticulum stress.Transcriptome sequencing analysis revealed that recombinant tissue plasminogen activator upregulated the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway in neurons.Moreover,the phosphoinositide 3-kinase inhibitor LY294002 abrogated the neuroprotective effects of recombinant tissue plasminogen activator in inhibiting excessive apoptosis,autophagy,and endoplasmic reticulum stress.Furthermore,to specify the domain of recombinant tissue plasminogen activator responsible for its neuroprotective effects,various inhibitors were used to target distinct domains.It has been revealed that the epidermal growth factor receptor inhibitor AG-1478 reversed the effect of recombinant tissue plasminogen activator on the phosphoinositide 3-kinase/RAC-alpha serine/threonineprotein kinase/mammalian target of rapamycin pathway.These findings suggest that recombinant tissue plasminogen activator exerts a direct neuroprotective effect on neurons following intracerebral hemorrhage,possibly through activation of the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway.
文摘背景:腰椎退行性疾病是一种中老年人常见疾病,临床表现主要为腰背部疼痛和下肢功能障碍。传统上使用腰椎融合联合双侧椎弓根螺钉固定进行外科干预,但存在创伤大、并发症多等问题。而腰椎融合联合单侧椎弓根螺钉固定是一种新兴的微创治疗方式,具有较小的创伤和较低的并发症风险,已逐渐成为腰椎退行性疾病治疗的新选择。目的:探讨腰椎融合联合单侧椎弓根螺钉固定治疗腰椎退行性疾病的效果及优势。方法:通过检索中国知网和PubMed数据库2010年1月至2025年1月发表的相关文献,总结腰椎融合联合单侧椎弓根螺钉固定的临床研究及生物力学特点,以“腰椎融合术,单侧固定,双侧固定,生物力学,腰椎退行性疾病”为中文检索词,以“lumbar fusion,unilateral fixation,bilateral fixation,biomechanics,degenerative disease of the lumbar spine”为英文检索词,最终纳入70篇文献进行综述。结果与结论:①腰椎融合联合单侧椎弓根螺钉固定能有效减少手术创伤和术中失血量,提供与双侧椎弓根螺钉固定相似的生物力学稳定性,并降低邻近节段退变的风险;②单侧椎弓根螺钉固定在单节段及双节段腰椎退行性疾病治疗中已获得广泛认可,但在多节段腰椎退行性疾病中的应用效果仍需进一步研究;③腰椎融合联合单侧椎弓根螺钉固定为腰椎退行性疾病治疗提供了微创、安全的选择,未来需要更多高质量的研究验证其在复杂病例中的应用和长期疗效,进一步优化临床应用。
文摘背景:选择合适的陶瓷材料对口腔全瓷美学修复尤为重要。在口腔修复体美学性能研究中,多使用色差值和透光性作为评价指标,影响全瓷修复体色差和透光性的因素主要有陶瓷材料的种类、色调、厚度、加工工艺以及基牙颜色和粘接剂等。目的:探究材料种类及厚度对全瓷修复体美学性能的影响。方法:选取各类可切削陶瓷中6种代表性的材料(常规氧化锆ZR-ST、树脂基陶瓷RC、高透氧化锆ZR-TT、白榴石增强玻璃陶瓷LE、二硅酸锂玻璃陶瓷LD及长石质瓷FP),每种材料分别制备成0.8,1.0,1.5 mm厚的10.0 mm×12.5 mm长方体陶瓷试件,进行对应的表面处理后与树脂试件(代表基牙)粘接制成陶瓷-树脂复合体试件,测算粘接前后的CIEL^(*)a^(*)b^(*)、色差值ΔE及透光率值。结果与结论:①当基牙厚度未达到无限光学厚度时,陶瓷材料的种类和厚度共同影响修复体的颜色和透光率值。当陶瓷试件厚度不超过1.0 mm时,与树脂片粘接后的颜色普遍向蓝红趋近;当陶瓷试件厚度为1.5 mm时,与树脂片粘接后的颜色普遍向蓝绿趋近,提示在全瓷修复体比色时可通过颜色预补偿优化美学匹配。②除厚度1.5 mm ZR-ST陶瓷试件外,粘接后各组陶瓷试件与树脂片之间的色差值ΔE均低于5,0.8 mm ZR-ST陶瓷试件与树脂片之间的色差值ΔE接近3,1.0 mm ZR-TT陶瓷试件与树脂片之间的色差值ΔE小于3,提示在微创修复过程中,若患牙透光率不高且美学修复空间不足、对材料强度要求高时,ZR-TT和ZR-ST陶瓷可能是潜在的选择。③陶瓷试件的透光率值在粘接后降低,并随陶瓷厚度的增加显著降低。RC陶瓷试件的透光率值高,粘接后与树脂片之间的色差值ΔE接近3,光学性能出色。
