Many applications of wireless sensor networks can benefit from fine-grained localization. In this paper, we proposed an accurate, distributed localization method based on the time difference between radio signal and sound wave. In a trilateration, each node adaptively chooses a neighborhood of sensors and updates its position estimate with trilateration, and then passes this update to neighboring sensors. Application examples demonstrate that the proposed method is more robust and accurate in localizing node than the previous proposals and it can achieve comparable results using much fewer anchor nodes than the previous methods.

BACKGROUND:Shear mechanical properties of lumbar trabecular bone should be understood in treating osteoporosis,bone remodeling,bone reconstruction,as well as the choice of fracture fixed equipment.OBJECTIVE:To explore whether the shear mechanical properties of lumbar trabecular bone is different in young and aged normal fresh cadavers.METHODS:Experimental samples were from 4 normal fresh corpse,aged 22,28,70 and 75 years,were provided by Department of Anatomy,Norman Bethune Medical University.Spinal column thoracic vertebra L_2-L_5 specimen were obtained from corpse within 1 hour and cut into 40 min×5 mm×5 mm pieces.The specimen were tested on electronic universal testing machine with speed of 5 mm/min,the shear load,stress,strain and other data would be printed automatically,and the morphology of fracture surface was observed.RESULTS AND CONCLUSION:Majority of the fracture surfaces were comminuted,minority were transverse or oblique fracture.The macroscopic observation showed that trabecular arranged compact in the thoracic vertebra cancellous bone of the youth group,which was sparse arrangement and presented with senile osteoporosis in the aged group.The shear force,shear stress and strain of the youth group was greater than that of the aged group[(37.19±3.25),(28.34±3.42) N;(1.49+0.13),(1.13±0.14) MPa;(1.40±0.50)%,(0.90±0.20)%,P＜0.05].It demonstrated that the impact mechanics properties of thoracic vertebra cancellous bone are different between the youth and aged groups.

BACKGROUND:The brachial plexus injury anastomosis suture technique is necessary to understand the mechanics characteristic of brachial plexus nerve stress relaxation.Previous studies mainly focused on single tension mechanics of brechial plexus nerve,but few studies concerning stress relaxation and creeping elasticity.OBJECTIVE:To observe and analyze experimental animal brachial plexus nerve stress relaxation mechanics characteristic in the description manner of function,to provide experimental parameters for clinic.DESIGN,TIME AND SETTING:The experimental observations to use function as a way to describe from 1~(st) to 10~(th_ March,2007 at the Experimental Center of Jilin University.MATERIALS:The experimental male Sprague Dawley rats aged 6 months were provided by Changchun Gaoxin Medicine Animal Experimentation Center.METHODS:The stress relaxation experiment was performed in Experimental animal Brachial plexus Nerve on the the electronic universal testing machine (Shimadzu,Japan).The stress relaxation experiment strain increased speed was 1%/s,setting time of 7 200 seconds.100 empirical data were collected and disposed by one-way linear regression analysis.MAIN OUTCOME MEASURES:The stress relaxation data and curve,the Stress and time change rule were measured.RESULTS:The stress relaxation quantity of animal brachial plexus nerve test specimen at 7 200 s was 0.316 MPa.Stress relaxation curve changed with logarithm.Stress relaxation changed rapidly at 600 seconds,decreased gradually,and reached a balance level at 7 200 seconds.CONCLUSION:The stress relaxation curve changed with the logarithm relations.Brachial plexus has visco-elastic mechanical properties.

Objective To explore the value of linear blending and non-linear blending images of dual-energy CT in improving the image quality of portal venography.Methods 60 patients clinically confirmed as liver cirrhosis with portal hypertension and gastric fundus esophageal varices were enrolled in the study.The patients underwent dual-energy (Sn140/80 kVp) scans in the portal phase, and four groups with 80 kVp and 140 kVp were defined as group A (linear blending images with M=0.3), B (linear ones with M=1.0), C (non-linear ones with c=150 and w=200) and D [non-linear ones with c=(CThepatic portal+CThepatic parenchymal)/2 and w=(CThepatic portal-CThepatic parenchymal)/2, and the CThepatic portal and CThepatic parenchymal were measured on M=0.3 image].The in portal vein enhancements, image noise, signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) and CT value difference between portal vein and liver parenchyma among four groups were compared by one-way ANOVA analysis of variance test.VRT imaging quality among four groups were assessed by Kruskal-Wallis test and Mann-Whitney U test.Results In four groups, the SNR and CNR of portal vein,and the CT value difference between portal vein and liver parenchyma(14.36 HU±3.23 HU,9.78 HU±2.39 HU,107.66 HU±21.28 HU) of group D were the highest (F=34.94,68.10 and 162.43,all P<0.01),and VRT image quality score of group D(4.78±0.42) was the best when compared to others (all P<0.01).Conclusion Non-linear blending technique of group D can improve the image quality of CT portography, which may be used in clinical practice.

OBJECTIVETo assess the efficacy and safety of hyaluronate sodium (HS) for internal derangement of temporomandibular joint by means of systematic review on relevant randomized controlled trials.

METHODSAfter identifing the study question of the efficacy and safety of HS for internal derangement of temporomandibular joint, Medline, Cochrane Controlled Trials Register, EMBASE, OPEN SIGLE and CBM were searched electronically till October 3rd 2010. Hand-searching covering 19 dental journals in Chinese were also performed. Risk of bias assessment, with Cochrane Collaboration's tool, and data extraction of included studies were conducted by two reviewers in duplicate. Meta analysis was done with Revman 5.0.23 and the quality of evidence was evaluated by GRADE.

RESULTS10 randomized controlled trials met the eligibility criteria and were included. All these studies had unclear risk of bias. When compared with negative control, HS showed a significant advantage on maximal mouth opening in short and long-term (P < 0.05), and clinical overall assessment in short-term (P < 0.05), but its effect on pain control and long-term effect on clinical overall assessment had no extra benefit (P > 0.05). Additionally, when compared with glucocorticoids, the participants who received HS injection would get a better clinical overall assessment in short-term and less adverse drug reactions (P < 0.05), but presented a similar temporomandibular joint pain relief and maximal mouth opening (P > 0.05).

CONCLUSIONTo a certain extent, HS had good efficacy and better safety than controls when treating internal derangement of temporomandibular joint. However, as the quality of some included studies were limited, more randomized controlled trials are needed to reinforce the conclusion.

Objective To construct the theoretical framework of rehabilitation big data based on International Classification of Func-tioning,Disability and Health(ICF). Methods Drawing upon international rehabilitation policy documents,such as the World Health Organization's Rehabili-tation in health systems;Rehabilitation in health systems:guide for action;Rehabilitation indicator menu:a tool accompanying the Framework for Rehabilitation Monitoring and Evaluation(FRAME);Template for Rehabilita-tion Information Collection(TRIC):a tool accompanying the Systematic Assessment of Rehabilitation Situation(STARS);and Framework and Standards for Country Health Information Systems;this study examined the com-position and function of rehabilitation big data.The content structure of the rehabilitation big data domain was an-alyzed using the World Health Organization Family of International Classifications(WHO-FICs).Furthermore,the generation patterns of rehabilitation big data was constructed drawing on the Health Metrics Network and big data hierarchical classification. Results Within the six primary elements of the health service system,the information system element was particularly significant,encompassing a substantial branch known as rehabilitation big data.There were three components of rehabilitation big data:health condition,health-related factors and health services.The content framework for this data was derived from the WHO-FICs framework,which covered three dimensions:health and function,dis-ease and function,and disease,function and intervention.A comprehensive model for generating and applying re-habilitation big data in rehabilitation services was developed in line with the requirements for constructing big da-ta architectures.The sources of this data included population censuses,social registration information,population surveys,resources,services and personal records.The result chain of rehabilitation big data encompassed five major processes:input,process,output,outcome and impact.The processing and utilization of this data involved collection,storage,management,analysis and application. Conclusion A theoretical framework for rehabilitation big data has been constructed based on the ICF theory.

Objective To explore and organize the standards of rehabilitation big data. Methods The connotation and extension of rehabilitation big data were discussed based on International Classification of Functioning,Disability and Health(ICF)framework.Referring to the documents of Guidance on the analysis and use of routine health information systems rehabilitation module,Rehabilitation in health systems:guide for action,Rehabilitation indicator menu:a tool accompanying the Framework for Rehabilitation Monitoring and Evaluation(FRAME),and Data quality assurance.Module 1.Framework and metrics,the sources,patterns,clas-sification systems and coding standards were discussed under the ICF theory,and the metadata standards were ex-plored.The application and management of rehabilitation big data standards were discussed according to Nation-al Health Medical Big Data Standards,Security and Service Management Measures(Trial). Results The rehabilitation big data included rehabilitation service data and personal health data,coming from population-based and institution-based data,covering macro,meso and micro levels.The pattern of rehabilitation data flow corresponded to the interaction and source of the entire process of rehabilitation service,to organize and manage rehabilitation big data.The classification system included object classes,object feature classes,participant role classes,relationship classes,and activity and event classes,each of which was further subdivided into subcatego-ries to cover the entities,features,roles,relationships and activities involved in the rehabilitation process.The metadata standards included three levels:core,general and specialized metadata,ensuring standardized manage-ment,sharing and interoperability of rehabilitation data. Conclusion This study delves into the standardization of rehabilitation big data based on the ICF framework,encompass-ing multiple dimensions such as the connotation and extension of rehabilitation big data,data sources,data mod-els,classification systems,coding standards,and metadata standards.The construction of a rehabilitation big data standard system involves standardization efforts in various aspects,including data content,data structure,data coding,and metadata.These standards not only adhere to the norms of data flow,but also take into account the complexity of data composition.This system aligns with health big data standards,ensuring data consistency,ac-curacy,and interoperability,thus providing a foundation for effective exchange and comparison between different data sources.The establishment of a rehabilitation big data standard system not only ensures the standardized pro-cessing of rehabilitation big data,but also lays a solid foundation for effective exchange between rehabilitation big data and other health data,as well as for the widespread application of rehabilitation big data.This provides crucial support for improving the quality and efficiency of rehabilitation services,ensuring that patients receive appropriate care,rehabilitation and support.It holds significant theoretical and practical implications for promot-ing the development of the rehabilitation field.

Objective To evaluate the short-term efficacy and safety of percutaneous liver puncture for local management of portal vein thrombosis(PVT).Methods Variations in thrombus,blood flow,and laboratory examination results were observed before and after percutaneous liver puncture in 197 patients with PVT,and the occurrence of comorbidities was recorded and followed up for one year after treatment.Results After treatment,the thrombus in the main portal vein vessels almostly disappeared in 119 patients(60.41％)with PVT,the thrombus had a significant reduction in 57 patients(28.93％),and the thrombus had a smaller change or an increase in 21 patients(10.66％);146 patients(74.11％)had smooth blood flow in the main portal vein vessels,29 patients(14.72％)showed significant improvement in blood flow,and 22 patients(11.17％)showed no significant improvement or worsening of blockage.The mean portal venous pressure was significantly lower than that before treatment(P＜0.001);thrombin time,activated partial thromboplastin time,and prothrombin time were prolonged compared to those before thrombolysis(P＜0.001),and fibrinogen were reduced compared to those before thrombolysis(P＜0.001).A total of 35 patients(17.77％)occured comorbidities during treatment.One year after treatment,196 patients(99.49％)with PVT survived,of which thrombus essentially disappeared in 141(71.94％),thrombus stabilized(or decreased)in 42(21.43％),and thrombus increased in 13(6.63％).Conclusion percutaneous liver puncture for local management of PVT is effective and reliable in the short-term and requires standardized management of the entire process.

Objective To explore the effects of monocular deprivation(MD)on the expression of astrocytes in the superior colliculus,hippocampus,and visual cortex in mice during the critical period of visual development.Methods Eighteen C57BL/6J mice were randomly divided into the normal control group(CON group)and the MD group,with 9 mice in each group.Mice were bred under the 12 h/12 h dark/light conditions.Mice in the CON group received no treat-ment,while mice in the MD group underwent MD of the right eye on postnatal day 27,and the tissue was removed after 7 days.The mRNA and protein expression levels of glial fibrillary acidic protein(GFAP)in the superior colliculus,hippo-campus and visual cortex of mice in the two groups were detected using the real-time reverse transcription quantitative pol-ymerase chain reaction(RT-qPCR)and Western blot,respectively.The number of astrocytes labeled by GFAP and central nervous system specific protein β(S100β)in the superior colliculus,hippocampus and visual cortex of mice in the two groups was detected using the immunofluorescence staining.Results RT-qPCR and Western blot results showed that compared with the CON group,the mRNA and protein expression levels of GFAP in the superior colliculus,hippocampus(CA1,CA3 and dentate gyrus)and visual cortex of mice in the MD group decreased,and the differences were statistically significant(all P＜0.05).The immunofluorescence staining results showed that compared with the CON group,the number of GFAP and S1OOβ co-labeled astrocytes in the superior colliculus,hippocampus(CA1,CA3 and dentate gyrus)and visual cortex of mice in the MD group decreased,and the differences were statistically significant(all P＜0.05).Conclusion MD of mice during the critical period of visual development can result in a decrease in the number of astrocytes in the supe-rior colliculus,hippocampus and visual cortex.

The study presents a method for the personalized biomechanical modeling of the human head and validates the generated model.Based on the TUST 50th percentile head biomechanical model,the method utilizes head CT data of the target model,and employs three-dimensional point cloud registration and free-form deformation techniques to rapidly develop a personalized head finite element model with detailed brain tissue structures.By reconstructing classic cadaver tests,it is found that the personalized head biomechanical model created by the proposed method shows a good consistency with the results of cadaver tests in kinematic and biomechanical responses.Furthermore,no significant differences are observed when compared with the head biomechanical model developed using reverse engineering method,thus verifying the effectiveness of the developed model.Consequently,the proposed method can be used to quickly construct personalized head biomechanical models with detailed anatomical structures,providing a fundamental computational analysis tool for researches in injury biomechanics,clinical medicine,and forensic identification.