59 research outputs found

    Real-Time Attitude and Orbit Control System of a Small LEO Satellite with Parallel-Processing Approach in a Ground Station

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    A Real-time Attitude and Orbit Control System (AOCS) using a parallel processing approach will be implemented using a Satellite Ground Control Station (SGCS). With this approach, the satellite will collect platform (attitude reference) and payload measurements (at 1Hz) over several orbits and down-link to the SGCS (at 5 KHz) where the real-time filtering, fault detection, diagnosis and corrective (if needed) control is generated. The control commands are up-linked to the satellite before losing telemetry lock. A substantial reduction in on-board computation can provide a cheaper and a higher reliable AOCS. In the proposed scheme, an advanced real-time estimation and control algorithm in the SGCS for monitoring the critical parameters of the system will be described for a gravity gradient stabilized Low Earth Orbit (LEO) satellite. The parallel (or distributed) processing technique effectively reduces the computation time and increases the subsystem performance dramatically where computation time becomes a critical factor due to the low earth orbit operation. The proposed scheme is based on (1) a Kalman Filter (KF) to perform the real-time estimation of the critical parameters, (2) a parallel processing technique to reduce the computation time, and (3) their implementation with an advanced control algorithm to reconfigure the complete AOCS from the SGCS (if necessary)

    Knee stability assessment on anterior cruciate ligament injury: clinical and biomechanical approaches

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    Anterior cruciate ligament (ACL) injury is common in knee joint accounting for 40% of sports injury. ACL injury leads to knee instability, therefore, understanding knee stability assessments would be useful for diagnosis of ACL injury, comparison between operation treatments and establishing return-to-sport standard. This article firstly introduces a management model for ACL injury and the contribution of knee stability assessment to the corresponding stages of the model. Secondly, standard clinical examination, intra-operative stability measurement and motion analysis for functional assessment are reviewed. Orthopaedic surgeons and scientists with related background are encouraged to understand knee biomechanics and stability assessment for ACL injury patients

    Retroperitoneoscopic Partial Nephrectomy in a Horseshoe Kidney

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    A 21-year-old woman with a 4 cm enhancing cystic renal mass in the left moiety of a horseshoe kidney was treated through a retroperitoneal laparoscopic approach. The tumor was excised completely with cold scissors, and renal parenchyma suturing with a surgical bolster was done with Vicryl 2-0 sutures. Choosing the proper approach according to the location of the lesion and the surgeon's experience with both approaches are of importance in laparoscopic surgery in horseshoe kidney cases. A preoperative kidney computed tomography angiography was helpful for understanding the complex renal vasculature

    PCR Marker-Based Evaluation of the Eating Quality of Japonica Rice (Oryza sativa L.)

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    Evaluation of eating quality in early breeding generations of rice is critical to developing varieties with better palatability. This paper reports DNA markers associated with eating quality of temperate japonica rice and an evaluation method aided by multiple regression analysis. A total of 30 markers comprising STSs, SNPs, and SSRs were tested for their association with palatability using 22 temperate japonica varieties with different palatability values. Eating quality-related traits of the 22 varieties were also measured. Of the 30 markers, 18 were found to be significantly associated with palatability and, consequently, a model regression equation with an R2 value of 0.99 was formulated to estimate the palatability by the marker data set. Validation of the model equation using selected breeding lines indicated that the marker set and the equation are highly applicable to evaluation of the palatability of cooked rice in temperate japonica varieties

    Comparison of two surgical techniques for reconstructing posterolateral corner of the knee: a cadaveric study evaluated by navigation system

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    Purpose: This study aimed to evaluate the immediate effect on knee kinematics by 2 different techniques of posterolateral corner (PLC) reconstruction. Methods: Five intact formalin-preserved cadaveric knees were used in this study. A navigation system was used to measure knee kinematics (posterior translation, varus angulation, and external rotation) after application of a constant force and torque to the tibia. Four different conditions of the knee were evaluated during the biomechanical test: intact knee and PLC-sectioned knee and PLC-reconstructed knee by the doublefemoral tunnel technique and singlefemoral tunnel technique. Results: Sectioning of the PLC structures resulted in significant increases in external rotation at 30° of flexion from 11.2° (SD, 2.6) to 24.6° (SD, 6.2), posterior translation at 30° of flexion from 3.4 mm (SD, 1.5) to 7.4 mm (SD, 3.8), and varus angulation at 0° of flexion from 2.3° (SD, 2.1) to 7.9° (SD, 5.1). Both reconstruction techniques significantly restored the varus stability. The external rotation and posterior translation at 30° of flexion after reconstruction with the doublefemoral tunnel technique were 10.2° (SD, 1.3) and 3.4° (SD, 2.7), respectively, which were significantly better than those of the singlefemoral tunnel technique. Conclusions: Both techniques of reconstruction showed improved stability compared with PLC-sectioned knees. The doublefemoral tunnel technique in PLC reconstruction showed better rotational stability and resistance to posterior translation than the singlefemoral tunnel technique without compromising varus stability. Clinical Relevance: PLC reconstruction by a doublefemoral tunnel technique achieves better rotational control and resistance to posterior translation

    Two Cases of Adrenal Abscesses Following Histoacryl® (N-butyl-2-cyanocrylate) Injection

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    We report two cases of adrenal abscesses that occurred following a Histoacryl® (N-butyl-2-cyanocrylate) injection for variceal bleeding. Patients had been diagnosed with alcoholic liver cirrhosis and gastric varices bleeding and received a Histoacryl® injection for the variceal bleeding. Patients had fever and abdominal tenderness and were diagnosed with an adrenal abscess at 2 months following the Histoacryl® injection. One patient received open drainage and the other underwent percutaneous drainage. When a patient has previously been injected with Histoacryl® for the treatment of variceal bleeding and presents with fever, an evaluation for an unusual complication such as adrenal abscess is recommended

    The disruption of proteostasis in neurodegenerative diseases

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    Cells count on surveillance systems to monitor and protect the cellular proteome which, besides being highly heterogeneous, is constantly being challenged by intrinsic and environmental factors. In this context, the proteostasis network (PN) is essential to achieve a stable and functional proteome. Disruption of the PN is associated with aging and can lead to and/or potentiate the occurrence of many neurodegenerative diseases (ND). This not only emphasizes the importance of the PN in health span and aging but also how its modulation can be a potential target for intervention and treatment of human diseases.info:eu-repo/semantics/publishedVersio
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