A Hybrid State/Disturbance Observer-Based Feedback Control of Robot with Multiple Constraints.

Controlling the manipulator is a big challenge due to its hysteresis, deadzone, saturation, and the disturbances of actuators. This study proposes a hybrid state/disturbance observer-based multiple-constraint control mechanism to address this difficulty. It first proposes a hybrid state/disturbance observer to simultaneously estimate the unmeasurable states and external disturbances. Based on this, a barrier Lyapunov function is proposed and implemented to handle output saturation constraints, and a back-stepping control method is developed to provide sufficient control performance under multiple constraints. Furthermore, the stability of the proposed controller is analyzed and proved. Finally, simulations and experiments are carried out on a 2-DOF and 6-DOF robot, respectively. The results show that the proposed control method can effectively achieve the desired control performance. Compared with several commonly used control methods and intelligent control methods, the proposed method shows superiority. Experiments on a 6-DOF robot verify that the proposed method has good tracking performance for all joints and does not violate constraints.

The preparation and electrochemical properties of Nd0.6Sr0.4Fe1-xZnxO3-δ cathode materials for intermediate temperature solid oxide fuel cells.

Nd0.6Sr0.4Fe1-xZnxO3-δ perovskite oxides were prepared by solid state synthesis and applied as solid oxide fuel cell (SOFC) cathodes. XRD showed the high uniformity of the synthesized powder. The addition of Zn reduces the coefficient thermal expansion (CTE), and the average CTE is 15.9279 × 10-6 K when the added Zn content is 0.1. Nd0.6Sr0.4Fe0.96Zn0.04O3-δ showed the highest conductivity of 108.78 S cm-1 at 700 °C. EIS indicated that an appropriate amount of Zn doping can improve the oxygen transport capacity. A single cell with Nd0.6Sr0.4Fe0.96Zn0.04O3-δ as the cathode showed a peak power density of 306.37 mW cm-2 at 800 °C, proving that the introduction of an appropriate amount of Zn can improve the electrochemical performance of a material.

Practice and thinking on teaching reform of Chinese medicine course Acupuncture-moxibustion Therapeutics based on "trinity" comprehensive evaluation / 中华医学教育探索杂志

Guided by the emphasis on learning process, the educational reform has designed a "trinity" comprehensive evaluation system (quantitative clinical practice, in-class medical record analysis, and staged comprehensive written test) as the formative evaluation of the course. Through this assessment system, students' self-learning potential is stimulated, clinical skills practice is strengthened, and "taking exams to promote learning and taking exams to promote teaching" is realized. In the practice of teaching reform, it has been found that compared with the conventional teaching class, the students in the teaching reform class have higher participation and are more satisfied with the process assessment of the "trinity" comprehensive evaluation system.

Discussion on the Problems of the Chief Review System in the Ethics Review of Clinical Research / 中国医学伦理学

By analyzing the problems such as the non-standard phenomenon in the implementation and operation of the current chief review system, the unclear responsibility of the chief review committee, and the lack of sound safeguard measures in the implementation of the chief review system, this paper put forward some suggestions, such as establishing and perfecting the chief review system of the ethics committee, clearly specifying the responsibilities and rights of the chief review committee, comprehensively strengthening the safeguard work and other improvement measures for the implementation of the chief review system, so as to provide suggestions for the more standardized and efficient operation of the chief review system in ethics review in China.

Analysis and Suggestions on Work Ethic Risk Factors of Caregivers of the Elderly with Disability and Dementia / 中国医学伦理学

Through the definition of the concepts of disabled and demented elderly, caregivers, work ethic, and ethical principles of caring for elderly with disability and dementia, this paper analyzed the ethical risk factors from the work ethics level of caregivers, the overall service ability and management level of care industry, the caregivers’ occupational burnout, and the degree of social public support and recognition of caregivers’ profession. It is proposed that paying attention to the cultivation of the caregivers’ work ethic quality, establishing the work ethic supervision and evaluation system of caregivers of the elderly with disability and dementia, exploring the successful experience of integrating ethic norms into the care of the elderly with disability and dementia, and safeguarding the rights and interests of the caregivers of the elderly with disability and dementia, so as to gradually reduce the work ethic risk of caregivers of the elderly with disability and dementia, improve the work ethic quality of caregivers, and safeguard the rights and interests of the disabled and demented elderly to the greatest extent.

Application of Microspectral Imaging in Motor and Sensory Nerve Classification.

Objective: It aimed to explore the application of the microscopic hyperspectral technique in motor and sensory nerve classification. Methods: The self-developed microscopic hyperspectral acquisition system was applied to collect the data of anterior and posterior spinal cord sections of white rabbits. The joint correction algorithm was employed to preprocess the collected data, such as noise reduction. On the basis of pure linear light source index, a new pixel purification algorithm based on cross contrast was proposed to extract more regions of interest, which was used for feature extraction of motor and sensory nerves. Besides, the ML algorithm was employed to classify motor and sensory nerves based on feature extraction results. Results: The joint correction algorithm was adopted to preprocess the data collected by the microscopic hyperspectral technique, so as to eliminate the influence of the incident light source and the system and improve the classification accuracy. The axon and myelin spectrum curves of the two kinds of nerves in the stained specimens had the same trend, but the values of all kinds of spectrum of sensory nerves were higher than those of motor nerves. However, the myelin sheath spectrum curves of motor nerves in the unstained specimens were greatly different from the curves of sensory nerves. The axon spectrum curves had the same trend, but the axon spectrum values of sensory nerves were higher than those of motor nerves. The ML algorithm had high accuracy and fast speed in motor and sensory nerve classification, and the classification effect of stained specimens was better than that of unstained specimens. Conclusion: The microscopic hyperspectral technique had high feasibility in sensory and motor nerve classification and was worthy of further research and promotion.

Study on Deposition Characteristics of Microparticles in Terminal Pulmonary Acini by IB-LBM.

As an indicator of health risk, the deposition of microparticles in terminal pulmonary acini is of great significance in the medical field. To control particulate pollution and optimize aerosol delivery, it is necessary to perform an in-depth study of the microparticle deposition in terminal pulmonary acini; however, little research has been done on this topic. This paper proposes a respiratory movement model of terminal pulmonary acini using an immersed boundary-lattice Boltzmann method. In addition, we explored the effect of gravity direction, respiratory rate, microparticle diameter, and other parameters on the microparticles deposition process and distribution, under the airflow in the acinar wall. It was found that the deposition of microparticles is sensitive to gravity direction, and the growth of the respiratory rate increases the rate of microparticle migration and deposition. It was observed that the gravity effect is enhanced by increasing the diameter of microparticles, causing a high deposition and dispersion rate. The study reveals the dynamic correlation between the respiration process and the movement of microparticles, which is of reference value to figure out the pathogenicity mechanism of inhalable particles and to optimize the aerosol delivery.

Genetic polymorphisms in metabolic enzymes and transporters have no impact on mycophenolic acid pharmacokinetics in adult kidney transplant patients co-treated with tacrolimus: A population analysis.

WHAT IS KNOWN AND OBJECTIVE: Mycophenolate mofetil, an ester prodrug of mycophenolic acid (MPA), is widely used to prevent graft rejection after kidney transplantation. The pharmacokinetic (PK) of MPA has been extensively studied, which revealed a high degree of variability. An integrated population PK (PopPK) model of MPA and its main metabolite mycophenolic acid glucuronide (MPAG) was developed using the adult patients who underwent kidney transplant and were administered oral mycophenolate mofetil combined with tacrolimus. METHODS: In total, 917 MPA and 740 MPAG concentrations in191 adult patients were analysed via nonlinear mixed-effects modelling. The concentration-time data were adequately described using a chain compartment model, including central and peripheral compartments for MPA and a central compartment for MPAG. Stepwise forward inclusion and backward elimination procedures were used to investigate the effects of genetic polymorphisms, including in UGT1A8, UGT1A9, UGT2B7, ABCB1, ABCC2, ABCG2, SLCO1B1, SLCO1B3, and HNF1α. RESULTS AND DISCUSSION: These genetic polymorphisms in metabolic enzymes and transporters have no obvious impact on the PK of MPA in adult patients who underwent kidney transplant and were co-treated with tacrolimus. The post-transplant time, serum albumin, and creatinine clearance were identified as significant covariates affecting the PK of MPA and MPAG, which should be considered in the clinical use of mycophenolate mofetil. WHAT IS NEW AND CONCLUSION: We established a PopPK model of MPA and MPAG in Chinese adult patients who underwent kidney transplant and were co-treated with tacrolimus. Genetic polymorphisms in metabolic enzymes and transporters showed no obvious impact on MMF PK. A model-informed dosing strategy was proposed by the established model, and MMF dose adjustment should be based on ALB levels and the post-transplantation time.

Survival of children with recurrent medulloblastoma undergoing sequential therapy: an analysis of 101 cases / 中国当代儿科杂志

OBJECTIVE@#To study the clinical features of children with recurrent medulloblastoma (MB) and treatment regimens.@*METHODS@#A retrospective analysis was performed on 101 children with recurrent MB who were admitted to the hospital from August 1, 2011 to July 31, 2017. The children were followed up to July 31, 2020. The Kaplan-Meier method was used for survival analysis. The Cox regression model was used for multivariate regression analysis.@*RESULTS@#Of the 101 children, 95 underwent remission induction therapy, among whom 51 had response, resulting in a response rate of 54%. The median overall survival (OS) time after recurrence was 13 months, and the 1-, 3-, and 5-year OS rates were 50.5%±5.0%, 19.8%±4.0%, and 10%±3.3% respectively. There was no significant difference in the 5-year OS rate between the children with different ages (< 3 years or 3-18 years), sexes, pathological types, or Change stages, between the children with or without radiotherapy before recurrence or re-irradiation after recurrence, and between the children with different times to recurrence (< 12 months or ≥ 12 months after surgery) (@*CONCLUSIONS@#As for the recurrence of MB, although remission induction therapy again can achieve remission, such children still have a short survival time. Only reoperation can significantly prolong survival time, and therefore, early reoperation can be considered to improve the outcome of children with recurrent MB.

Clinical effect of surgery combined with chemotherapy and radiotherapy in children with central primitive neuroectodermal tumor and prognostic analysis / 中国当代儿科杂志

OBJCTIVE@#To study the clinical effect of surgery combined with chemotherapy and radiotherapy in children with central primitive neuroectodermal tumor (cPNET), as well as the risks factors for poor prognosis.@*METHODS@#A retrospective analysis was performed for the clinical data of 42 children who were diagnosed with cPNET from June 2012 to September 2018.@*RESULTS@#The 42 children had a median overall survival (OS) time of 2.0 years and a median event-free survival (EFS) time of 1.3 years; the 1-, 3-, and 5-year OS rates were 76.2%±6.6%, 41.4%±8.7%, 37.3%±8.8% respectively, and the 1-, 3-, and 5-year EFS rates were 64.3%±7.4%, 32.7%±8.0%, 28.0%±8.1% respectively. The univariate analysis showed that there were significant differences in the OS and EFS rates among the children with different patterns of surgical resection, chemotherapy cycles, and risk grades (P<0.05), and there was also a significant difference in the OS rate between the children receiving radiotherapy and those not receiving radiotherapy (P<0.05). The multivariate Cox regression analysis showed that chemotherapy cycles and risk grade were independent influencing factors for EFS and OS rates (P<0.05). The EFS and OS rates increased with the increase in chemotherapy cycles and the reduction in risk grade.@*CONCLUSIONS@#Multimodality therapy with surgery, chemotherapy, and radiotherapy is an effective method for the treatment of cPNET in children. Early diagnosis and treatment and adherence to chemotherapy for as long as possible may improve EFS and OS rates.

Effect of bevacizumab in treatment of children with optic pathway glioma / 中国当代儿科杂志

OBJECTIVE@#To investigate the effect of bevacizumab in the treatment of children with optic pathway glioma (OPG).@*METHODS@#A retrospective analysis was performed for the clinical data of 30 children with OPG who underwent chemotherapy. According to whether bevacizumab was used, they were divided into conventional chemotherapy (carboplatin, vincristine and etoposide) group with 12 children and combined chemotherapy (bevacizumab, carboplatin, vincristine and etoposide) group with 18 children. The children were followed up to 6 months after chemotherapy, and the two groups were compared in terms of visual acuity and tumor size before and after chemotherapy and adverse reactions during chemotherapy.@*RESULTS@#The combined chemotherapy group had a significantly higher proportion of children achieving tumor regression than the conventional chemotherapy group (P0.05). No chemotherapy-related death was observed in either group.@*CONCLUSIONS@#Bevacizumab combined with conventional chemotherapy can effectively reduce tumor size. Compared with conventional chemotherapy, such combination does not increase adverse reactions and can thus become a new direction for the treatment of OPG in children.

(image) of meridian sinew and meridian sinew differentiation in treatment with cupping therapy / 中国针灸

Cupping therapy is closely related to the meridian sinew system. " (image) of meridian sinew" is the reflection of " thinking" in meridian sinew system, e.g. morphology, function, color and lustre, temperature. Taking "(image) of meridian sinew" as the diagnosis object, the exploration is conducted in the paper in terms of classical theory, clinical practice and modern research. " (image) of meridian sinew" and "meridian sinew differentiation" are the important components in the improvement of cupping therapy system and the clinical development of acupuncture and moxibustion.

Risk factors for recurrence within 2 years in children with medulloblastoma / 中国当代儿科杂志

OBJECTIVE@#To investigate the risk factors for recurrence of medulloblastoma (MB) within 2 years and their influence on progression-free survival (PFS).@*METHODS@#A retrospective analysis was performed for the clinical data of 123 children with MB who were admitted from January to December, 2017. According to the presence or absence of recurrence, they were divided into recurrence group with 30 children and non-recurrence group with 93 children. The risk factors for recurrence within 2 years were analyzed, and PFS was compared between the children with different risk factors.@*RESULTS@#Large-cell/anaplastic type and M stage were risk factors for MB recurrence within 2 years. The risk of recurrence in the children with M+ MB was 3.525 times that in those with M0 MB, and the risk of recurrence in the children with large-cell/anaplastic MB was 3.358 times that in those with classic MB (P<0.05). The survival analysis showed that the median PFS time was 20 months in the children with M+ MB, and the 20-month PFS rate was 50% ± 11% in the children with M+ MB and 81% ± 5% in those with M0 MB (P<0.05). The 20-month PFS rate was 80% ± 5% in the children with classic MB, 65% ± 10% in those with desmoplastic/nodular MB, 86% ± 13% in those with MB with extensible nodularity, and 36% ± 20% in those with large-cell/anaplastic MB (P<0.05).@*CONCLUSIONS@#Recurrence is an important influencing factor for the prognosis of MB, and M+ stage and large-cell/anaplastic MB are risk factors for recurrence. Children with such risk factors tend to have a low PFS rate.

Effect of electroacupuncture on muscular atrophy and Slit/Robo signaling in sciatic nerve and lumbar spinal cord tissues in rats with sciatic nerve injury / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Huantiao"(GB30) and" Zusanli"(ST36)on muscular atrophy and expression of Slit-Robo GTPase-activating protein(srGAP)1, 2 and 3 in the injured sciatic nerve and lumbar spinal cord tissues in sciatic nerve injury (SNI) rats, so as to reveal its mechanisms underlying improvement of peripheral nerve injury (PNI)．. METHODS: A total of 120 healthy male SD rats were randomly divided into control, sham-operation, model and EA groups (n＝30 rats in each) which were further divided into 7, 15 and 23 d subgroups (n＝10 rats in each subgroup). The SNI model was established by transecting the right sciatic nerve beneath the piriformis and immediately subsequent end-to-end suture. Rats of the sham operation group received an incision of the corresponding skin and suture. EA (5 Hz/20 Hz, 2－3 mA) was applied to the right GB30 and ST36 for 15 min, once daily, 6 days a week separately for 1，2 and 3 weeks. Rats in the sham-operation and model groups were grasped in the similar procedure as the EA group. The wet weight of gastrocnemius muscles (WWG) on both sides was measured to calculate the recovery rate (weight of the right WWG/weight of the left WWG×100%), and the expression levels of srGAP1, srGAP2 and srGAP3 proteins in the sciatic nerve and the spinal cord (L4-L6) tissues were detected by Western blot. RESULTS: After modeling and compared with the control and sham-operation groups, the recovery rate of WWG was significantly reduced, and the expression levels of srGAP1, srGAP2 and srGAP3 proteins of the sciatic nerve and lumbar spinal cord on day 7, 15 and 23 were considerably increased in the model group (P<0.01). Following the EA treatment, the reco-very rate of WWG was obviously increased and the expression levels of srGAP1, srGAP2 and srGAP3 proteins of both sciatic nerve and spinal cord on day 7, 15 and 23 were further significantly up-regulated in the EA group relevant to the model group (P<0.05，P<0.01). In addition, the expression levels of the 3 proteins in both sciatic nerve and lumbar spinal cord peaked on day 15 and attenuated on day 23. CONCLUSION: EA of GB30 and ST36 may relieve gastrocnemius atrophy in SNI rats, which is related to its function in up-regulating the Slit/Robo signaling in the sciatic nerve and lumbar spinal cord to promote the axonal targeting regeneration and repair of axonal plasma nutrition transportation.

PXR polymorphisms have impact on the clinical efficacy of clopidogrel in patients undergoing percutaneous coronary intervention.

BACKGROUNDS: Clopidogrel is widely used in Coronary Heart Disease (CHD) patients undergoing percutaneous coronary intervention (PCI) to prevent thrombotic events. However, clopidogrel response variability (CRV) may affect the patients' clinical outcomes. The current data have shown that genetic factors play an important role in CRV. The aim of this research is to investigate the association of pregnane X receptor (PXR, also called NR1I2) genetic polymorphisms with the clinical efficacy of clopidogrel in patients undergoing PCI. METHODS: A total of 384 patients undergoing PCI were recruited and treated with dual antiplatelet therapy (DAPT) for 12 months. The plasma concentration of clopidogrel carboxylic acid metabolites (CLPM) was measured by High Performance Liquid Chromatography (HPLC). The maximum aggregation rate (MAR) of platelet were measured by PL-11 analyzer. PXR genetic polymorphisms were determined by Sequenom MassArray system. The clinical outcomes were observed by readmission, outpatient and calling back interview within 12 months after PCI. RESULTS: Among all 384 patients, a total of 153 patients were occurred with major adverse cardiovascular events (MACE), 29 patients were occurred with bleeding events, the other patients had a favorable prognosis. The polymprphisms of PXR rs3814057A > C [OR(95%CI): 0.71(0.527-0.957), P = 0.024], rs3814058T > C [OR (95%CI): 1.395(1.034-1.883), P = 0.029] and rs6785049 A > G [OR(95%CI): 0.724 (0.535-0.979), P = 0.036] were significantly associated with MACE. The haplotype h1 (GCC) was associated with a higher risk of MACE [OR (95%CI): 1.385 (1.028-1.866), P = 0.031]. Whereas, the haplotype h2 (AAT) was associated with a lower risk of MACE [OR (95%CI): 0.711(0.525-0.962), P = 0.027]. CONCLUSIONS: The genotypes and haplotypes of PXR rs3814057, rs3814058 and rs6785049 have impact on the MACE in clopidogrel treated patients after PCI.

Applications of Chest Wall Reconstructive Materials / 中国医学科学院学报

Chest wall reconstruction is a key approach to restoring the structure and function of the defective chest wall after tumor excision. While autologous flaps have been ideal materials for soft tissue reconstruction,the optimal skeletal reconstructive material still remains controversial. Currently,besides autologous bones,non-biodegradable materials have been used widely,which offer sufficient strength and stability but with some inevitable complications. Many studies have explored the clinical applications of biodegradable materials and the improvements in their characteristics,and some of these materials may be clinically feasible. This article reviews the recent advances in the applications of reconstructive materials.

FTUC: A Flooding Tree Uneven Clustering Protocol for a Wireless Sensor Network.

Clustering is an efficient approach in a wireless sensor network (WSN) to reduce the energy consumption of nodes and to extend the lifetime of the network. Unfortunately, this approach requires that all cluster heads (CHs) transmit their data to the base station (BS), which gives rise to the long distance communications problem, and in multi-hop routing, the CHs near the BS have to forward data from other nodes that lead those CHs to die prematurely, creating the hot zones problem. Unequal clustering has been proposed to solve these problems. Most of the current algorithms elect CH only by considering their competition radius, leading to unevenly distributed cluster heads. Furthermore, global distances values are needed when calculating the competition radius, which is a tedious task in large networks. To face these problems, we propose a flooding tree uneven clustering protocol (FTUC) suited for large networks. Based on the construction of a tree type sub-network to calculate the minimum and maximum distances values of the network, we then apply the unequal cluster theory. We also introduce referenced position circles to evenly elect cluster heads. Therefore, cluster heads are elected depending on the node's residual energy and their distance to a referenced circle. FTUC builds the best inter-cluster communications route by evaluating a cluster head cost function to find the best next hop to the BS. The simulation results show that the FTUC algorithm decreases the energy consumption of the nodes and balances the global energy consumption effectively, thus extending the lifetime of the network.

Characteristic analysis of pulmonary ground-glass lesions with the help of 64-slice CT technology.

OBJECTIVE: With the help of new technologies like 64-slice spiral CT, including latest AW4.4, 2D nodule comparing and analyzing technology, MPR and 3D technology, MIP technology and the technology of analyzing pulmonary vascular density by the method of perfusion scanning, we performed characteristic analysis of ground-glass opacities (GGO) for the early diagnosis of lung cancer. PATIENTS AND METHODS: We selected 62 patients suspected of lung cancer, whose conventional CT showed that they were patients with GGO. With the help of the new technologies of 64-slice spiral CT provided by GE Company, prospective scans were made and 2 to 4 times of review were arranged. After that, the patients were treated with surgery or needle biopsy to get lesion's pathological results. After several scans, the results including lesion's form, density, blood supply, peripheral sign, doubling time and tissue perfusion were drawn to make a comparison. Based on the results, comparative analysis on GGO's characteristics was made from morphological and functional perspectives. RESULTS: 41 patients (66.1%) were pathologically diagnosed with cancer, 10 were diagnosed with inflammation, 7 with fibrosis, and 4 with edema, hemorrhage and other lesions. The comparisons were made between the tumor groups' clinical manifestations (sex, age, symptoms including smoking, coughing, and expectoration), and the difference had no statistical significance (p>0.05). Conventional CT scan showed that the shape of GGO was irregular and it showed spiculated sign and pleural indentation. The proportion of the patients with vessel convergence in the tumor group was significantly higher than that of the non-tumor group (p<0.05). However, the comparisons between lesions' number, location (superior lobe of the right lung), diameter, edge (blur) and lobulation were made to get a difference ratio (p>0.05) which had no statistical significance. Tumor group's doubling time was significantly short, and its perfusion parameters including BF, BV, MTT, and PS were increased significantly (p<0.05). CONCLUSIONS: The new 64-slice CT technology has great value in the diagnosis of the tumorous GGO.

Astragaloside IV downregulates the expression of MDR1 in Bel­7402/FU human hepatic cancer cells by inhibiting the JNK/c­Jun/AP­1 signaling pathway.

Previous studies demonstrated that astragaloside IV (ASIV) is a potential P­glycoprotein (P­gp)­mediated multidrug resistance (MDR) reversal agent through mechanisms involving downregulation of the gene expression of mdr1. In order to investigate whether the c­Jun N­terminal kinase (JNK) signaling pathway is involved in the mechanism underlying ASIV­induced downregulated the expression of mdr1, the present study used 5­fluorouracil­resistant Bel­7402/FU human hepatic cancer cells as target cells. ASIV (0.1 mM) decreased the protein expression of phosphorylated (p)­JNK and p­c­Jun in the Bel­7402/FU cells, as determined using western blot analysis. Treatment with the JNK pathway inhibitor, SP600125, at a concentration of 11 µM, decreased the mRNA expression levels of mdr1 and P­gp, as determined using reverse transcription­quantitative polymerase chain reaction and western blot analyses, and similar effects were observed following exposure to ASIV. Furthermore, electrophoretic mobility shift assays demonstrated that the DNA­binding activity of activator protein­1 (AP­1) was decreased by 0.1 mM ASIV or 11 µM SP600125. Flow cytometric analysis revealed that 0.1 mM ASIV or 11 µM SP600125 increased the intracellular accumulation of fluorescent P­gp substrates, including rhodamine 123. Taken together, these results indicated that ASIV reversed the drug resistance of Bel­7402/FU cells by downregulating the expression of mdr1 via inhibition of the JNK/c­Jun/AP­1 signaling pathway.