A new measurement and analysis method was proposed to investigate the changes in elbow joint moments that occur with the use of a front-wheeled walker. A strain gauge-based walker instrumentation system was developed ...A new measurement and analysis method was proposed to investigate the changes in elbow joint moments that occur with the use of a front-wheeled walker. A strain gauge-based walker instrumentation system was developed to monitor the hand loads during walker-assisted walking and integrated with an upper extremity biomechanical model, Preliminary system data were collected for 12 subjects following informed consent. Bilateral upper extremity kinematic data were acquired with a six-camera motion analysis system. Internal joint moments at the elbow were determined in the three clinical planes using the inverse dynamics method. Results showed that during a walker-assisted gait elbow joint moments mainly distributed in the walker stance period. There was a noted demand on the elbow extensor in the sagittal plane with the greatest record as 0.381 N.m/(kg.m), An interesting “bare phase” of mean elbow joint moments was also found in phase angle-240°-340° of gait cycle. Complete description of elbow joint moments of walkerassisted gait may provide insight into walker use parameters and rehabilitative strategies.展开更多
Patients with brain tumors,specifically,malignant forms such as glioblastoma,medulloblastoma and ependymoma,exhibit dismal survival rates despite advances in treatment strategies.Chemotherapeutics,the primary adjuvant...Patients with brain tumors,specifically,malignant forms such as glioblastoma,medulloblastoma and ependymoma,exhibit dismal survival rates despite advances in treatment strategies.Chemotherapeutics,the primary adjuvant treatment for human brain tumors following surgery,commonly lack efficacy due to either intrinsic or acquired drug resistance.New treatments targeting epigenetic factors are being explored.Post-translational histone modification provides a critical regulatory platform for processes such as chromosome condensation and segregation,apoptosis,gene transcription,and DNA replication and repair.This work reviews how aberrant histone modifications and alterations in histone-modifying enzymes can drive the acquisition of drug resistance in brain tumors.Elucidating these mechanisms should lead to new treatments for overcoming drug resistance.展开更多
Today, one of the most important phenomenons is the movement of Capital and the expansion of its investments, as well as the use of resources worldwide. The movement of Capital, is changing the local space and the ter...Today, one of the most important phenomenons is the movement of Capital and the expansion of its investments, as well as the use of resources worldwide. The movement of Capital, is changing the local space and the territories, because is not a homogeneous process; they are not in the same way and rhythm, this is because they don't get in the same way to global dynamics. The reorganization of the world, because the movements in Capital is a challenge, that is why, the analysis of regions demand new and different views, to boost regional development. We can tell that since a long time ago, had been developing theories and proposals not good enough, for this reason we must think to generate new proposals. The goal of this paper, is to expose the social and territorial changes in Silao and Romita Counties in the state of Guanajuato Mexico, as a result of the relocation of economic activities that lead us to start a new regional policy, that gives more satisfactory results and think about a regional policy that could reflex about territorial development focuses, specially for a public policy.展开更多
Existing hydraulic braking systems in the vehicle is composed of the brake pedal, the hydraulic booster and the hydraulic caliper. The driver transmits one's breaking intent through the brake pedal stroke and force. ...Existing hydraulic braking systems in the vehicle is composed of the brake pedal, the hydraulic booster and the hydraulic caliper. The driver transmits one's breaking intent through the brake pedal stroke and force. The hydraulic booster can amplify the pedal force, only when the engine operates. The hydraulic caliper is composed of cylinders, pistons. There are also hydraulic pipes from the booster to the caliper. Currently, X-By-Wire technology is researched actively due to the exhaustion of fuel and the regulation of CO2. As a chain of this trend, the e-pedal and an electric mechanical brake (EMB) also are highlighted. At the beginning of EMB development, high-torque and high-power motors are required in order to implement the existing hydraulic calipers' clamping force. This has some limits as the need of big spaces and high costs. Then the electro wedge brake (EWB) is launching with self-reinforcement features of the wedge structure. EWB can generate big clamping forces with small size and low-torque motors with good braking-efficiency. In recent, the disc's circumferential face clamping one has been researched, for better heat-emission ability and better braking-efficiency compared to the existing disc's lateral face clamping method. But, this circumferential face clamping method can have worse unbalance-wear features compared to lateral face clamping one. In this study, the authors describe their circumferential EWB concepts, the method for reducing unbalance-wear feature of circumferential EWB, and the cost-effective implementation of circumferential EWB, in particular focused on nonlinear counter-wedge profile which is appropriate to reduce unbalance-wear.展开更多
This paper addresses the gas path component and sensor fault diagnosis and isolation(FDI) for the auxiliary power unit(APU). A nonlinear dynamic model and a distributed state estimator are combined for the distributed...This paper addresses the gas path component and sensor fault diagnosis and isolation(FDI) for the auxiliary power unit(APU). A nonlinear dynamic model and a distributed state estimator are combined for the distributed control system. The distributed extended Kalman filter(DEKF)is served as a state estimator,which is utilized to estimate the gas path components’ flow capacity. The DEKF includes one main filter and five sub-filter groups related to five sensors of APU and each sub-filter yields local state flow capacity. The main filter collects and fuses the local state information,and then the state estimations are feedback to the sub-filters. The packet loss model is introduced in the DEKF algorithm in the APU distributed control architecture. FDI strategy with a performance index named weight sum of squared residuals(WSSR) is designed and used to identify the APU sensor fault by removing one sub-filter each time. The very sensor fault occurs as its performance index WSSR is different from the remaining sub-filter combinations. And the estimated value of the soft redundancy replaces the fault sensor measurement to isolate the fault measurement. It is worth noting that the proposed approach serves for not only the sensor failure but also the hybrid fault issue of APU gas path components and sensors. The simulation and comparison are systematically carried out by using the APU test data,and the superiority of the proposed methodology is verified.展开更多
基金National Natural Science Foundation of China (No. 60501005)National High Technology Research and Development Program of China(No. 2007AA04Z236)Key Program of Tianjin Science and Technology Support Plan (No. 07ZCKFSF01300)
文摘A new measurement and analysis method was proposed to investigate the changes in elbow joint moments that occur with the use of a front-wheeled walker. A strain gauge-based walker instrumentation system was developed to monitor the hand loads during walker-assisted walking and integrated with an upper extremity biomechanical model, Preliminary system data were collected for 12 subjects following informed consent. Bilateral upper extremity kinematic data were acquired with a six-camera motion analysis system. Internal joint moments at the elbow were determined in the three clinical planes using the inverse dynamics method. Results showed that during a walker-assisted gait elbow joint moments mainly distributed in the walker stance period. There was a noted demand on the elbow extensor in the sagittal plane with the greatest record as 0.381 N.m/(kg.m), An interesting “bare phase” of mean elbow joint moments was also found in phase angle-240°-340° of gait cycle. Complete description of elbow joint moments of walkerassisted gait may provide insight into walker use parameters and rehabilitative strategies.
基金Supported by the Rory David Deutsch Foundationthe Surgical Neuro-oncology Research Fund of Ann&Robert H Lurie Children’s Hospital(A&RLCH) of Chicagothe Dr.Ralph and Marian C.Falk Medical Research Trust
文摘Patients with brain tumors,specifically,malignant forms such as glioblastoma,medulloblastoma and ependymoma,exhibit dismal survival rates despite advances in treatment strategies.Chemotherapeutics,the primary adjuvant treatment for human brain tumors following surgery,commonly lack efficacy due to either intrinsic or acquired drug resistance.New treatments targeting epigenetic factors are being explored.Post-translational histone modification provides a critical regulatory platform for processes such as chromosome condensation and segregation,apoptosis,gene transcription,and DNA replication and repair.This work reviews how aberrant histone modifications and alterations in histone-modifying enzymes can drive the acquisition of drug resistance in brain tumors.Elucidating these mechanisms should lead to new treatments for overcoming drug resistance.
文摘Today, one of the most important phenomenons is the movement of Capital and the expansion of its investments, as well as the use of resources worldwide. The movement of Capital, is changing the local space and the territories, because is not a homogeneous process; they are not in the same way and rhythm, this is because they don't get in the same way to global dynamics. The reorganization of the world, because the movements in Capital is a challenge, that is why, the analysis of regions demand new and different views, to boost regional development. We can tell that since a long time ago, had been developing theories and proposals not good enough, for this reason we must think to generate new proposals. The goal of this paper, is to expose the social and territorial changes in Silao and Romita Counties in the state of Guanajuato Mexico, as a result of the relocation of economic activities that lead us to start a new regional policy, that gives more satisfactory results and think about a regional policy that could reflex about territorial development focuses, specially for a public policy.
文摘Existing hydraulic braking systems in the vehicle is composed of the brake pedal, the hydraulic booster and the hydraulic caliper. The driver transmits one's breaking intent through the brake pedal stroke and force. The hydraulic booster can amplify the pedal force, only when the engine operates. The hydraulic caliper is composed of cylinders, pistons. There are also hydraulic pipes from the booster to the caliper. Currently, X-By-Wire technology is researched actively due to the exhaustion of fuel and the regulation of CO2. As a chain of this trend, the e-pedal and an electric mechanical brake (EMB) also are highlighted. At the beginning of EMB development, high-torque and high-power motors are required in order to implement the existing hydraulic calipers' clamping force. This has some limits as the need of big spaces and high costs. Then the electro wedge brake (EWB) is launching with self-reinforcement features of the wedge structure. EWB can generate big clamping forces with small size and low-torque motors with good braking-efficiency. In recent, the disc's circumferential face clamping one has been researched, for better heat-emission ability and better braking-efficiency compared to the existing disc's lateral face clamping method. But, this circumferential face clamping method can have worse unbalance-wear features compared to lateral face clamping one. In this study, the authors describe their circumferential EWB concepts, the method for reducing unbalance-wear feature of circumferential EWB, and the cost-effective implementation of circumferential EWB, in particular focused on nonlinear counter-wedge profile which is appropriate to reduce unbalance-wear.
基金supported by the National Natural Science Foundation of China(No.91960110)the National Science and Technology Major Project(No. 2017-I0006-0007)the Fundamental Research Funds for the Central Universities(NP2022418)。
文摘This paper addresses the gas path component and sensor fault diagnosis and isolation(FDI) for the auxiliary power unit(APU). A nonlinear dynamic model and a distributed state estimator are combined for the distributed control system. The distributed extended Kalman filter(DEKF)is served as a state estimator,which is utilized to estimate the gas path components’ flow capacity. The DEKF includes one main filter and five sub-filter groups related to five sensors of APU and each sub-filter yields local state flow capacity. The main filter collects and fuses the local state information,and then the state estimations are feedback to the sub-filters. The packet loss model is introduced in the DEKF algorithm in the APU distributed control architecture. FDI strategy with a performance index named weight sum of squared residuals(WSSR) is designed and used to identify the APU sensor fault by removing one sub-filter each time. The very sensor fault occurs as its performance index WSSR is different from the remaining sub-filter combinations. And the estimated value of the soft redundancy replaces the fault sensor measurement to isolate the fault measurement. It is worth noting that the proposed approach serves for not only the sensor failure but also the hybrid fault issue of APU gas path components and sensors. The simulation and comparison are systematically carried out by using the APU test data,and the superiority of the proposed methodology is verified.