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find Keyword "theory" 37 results
  • The research on dynamic properties of the small world neural network based on the synaptic plasticity

    The artificial neural network has the ability of the information processing and storage, good adaptability, strong learning function, association function and fault tolerance function. The research on the artificial neural network is mostly focused on the dynamic properties due to fact that the applications of artificial neural networks are related to its dynamic properties. At present, the researches on the neural network are based on the hierarchical network which can not simulate the real neural network. As a high level of abstraction of real complex systems, the small world network has the properties of biological neural networks. In the study, the small world network was constructed and the optimal parameter of the small word network was chosen based on the complex network theory firstly. And then based on the regulation mechanism of the synaptic plasticity and the topology of the small world network, the small world neural network was constructed and dynamic properties of the neural network were analyzed from the three aspects of the firing properties, dynamic properties of synaptic weights and complex network properties. The experimental results showed that with the increase of the time, the firing patterns of excitatory and inhibitory neurons in the small world neural network didn’t change and the firing time of the neurons tended to synchronize; the synaptic weights between the neurons decreased sharply and eventually tended to be steady; the connections in the neural network were weakened and the efficiency of the information transmission was reduced, but the small world attribute was stable. The dynamic properties of the small world neural network vary with time, and the dynamic properties can also interact with each other: the firing synchronization of the neural network can affect the distribution of synaptic weights to the minimum, and then the dynamic changes of the synaptic weights can affect the complex network properties of the small world neural network.

    Release date:2018-08-23 05:06 Export PDF Favorites Scan
  • APPLICATION OF ILIZAROV S THEORY AND TECHNIQUE IN THE TREATMENT Oq CONGENITAL PSEUDARTHROSIS OF THE TIBIA

    Abstract There have been many types of bone-grafting operation dealing with the congenital pseudarthrosis of the tibia (CPAT), but the failure rate is fairly high. Since 1990, 2 children with CPAT, who had received repeated bone-grafting operation in failure, were treatedaccordingto the Ilizarovs theory and its related technique. The essentials of the operation were: (1) Thorough resection of abnormal bone tissues at pseudarthrosis might freshen the ends of the bone and facilitate bone union. (2) The firm fixation and constant compression force to the bone ends might promote bone healing. (3) The tibial lengthening was performed by osteotomy at the upper tibia. The pseudarthrosis was united in 2~3 months after operation. The patients were followed up from 1 to 3 years, and it was found that the remodelling of thebone was good, no recurrence occured. The advantages were: (1) The bone grafting was no longer necessary. (2) It could give a chance to equalizethe limb length. (3) It could enable early weight bearing and functional exercise.

    Release date:2016-09-01 11:10 Export PDF Favorites Scan
  • Vision for the future development of day surgery in China

    Although day surgery started late in China, its development momentum is strong. Due to the advantages of day surgery, the requirements of new medical reform and the promotion of national policies, thousands of hospitals have tried this innovative operation management mode in the past decade, presenting a picture of blooming flowers in full bloom. However, due to the lack of unified management standards for day surgery in China, there are still many practical problems in China, such as inconsistent definitions, inconsistent connotations and diversified management modes. It is believed that the day surgery will develop healthily and sustainably in China after the relevant management standards are formulated at the national level. Based on the development of day surgery at home and abroad, this paper discusses the expectation and prospect of day surgery in China.

    Release date:2021-03-19 01:22 Export PDF Favorites Scan
  • Application of graph theory-based brain network in developmental and epileptic encephalopathy

    Developmental and epileptic encephalopathy (DEE) is a group of diseases that severely affects the neurological development of children, characterized by frequent seizures and significant neurodevelopmental impairments. These diseases not only impact the quality of life of affected children but also impose a heavy burden on families and society. In recent years, the development of brain network theory has provided a new perspective on understanding the pathological mechanisms of DEE, especially the role of structural and functional brain networks in the process of epilepsy. This review systematically summarized the research progress of structural and functional brain networks in DEE, highlighted their importance in seizure activity, disease progression, and prognosis evaluation.

    Release date:2025-01-11 02:34 Export PDF Favorites Scan
  • Transcatheter edge-to-edge repair: Operating theories, basic principles, and predictors of prognosis

    Mitral regurgitation is one of the most common heart valve diseases. Transcatheter edge-to-edge repair (TEER) is currently the most developed and commonly used interventional technique for mitral regurgitation and is recommended by the latest European and American guidelines for patients who are at high surgical risk. TEER device usually consists of a clamping device and a delivery system. The trajectory of the clamping device is called the trajectory, and the trajectory can be well established with the five dimensions movement of the delivery system: left-right oscillation, anterior-posterior oscillation, overall parallel movement, the clamping device's own clockwise rotation, and vertical up-and-down movement. The delivery system's anteroposterior and lateral oscillations are concentrated on the virtual puncture site. Furthermore, the location of the septal puncture site has a significant impact on the establishemnt of the trajectory. The evulation of three variables and adherence to the "4M principles" are necessary for the successful TEER. The three variables are: the position of the clip in the center of the regurgitation,the arm orientation of the clip perpendicular to the boundary of anterior and posterior leaflets, as well as the appropriate length of clamping. The "4M principles" include favorable valve morphology, residual mitral regurgitation below grade 2+, mean transvalvular pressure≤5 mm Hg, and an appropriate amount of leaflets clamping. Patients' baseline situation, the degree of mitral regurgitation and ventricular remodeling, as well as the valve morphology and the outcome of the procedure, are the factors determining the prognosis of patients after TEER.

    Release date:2022-08-25 08:52 Export PDF Favorites Scan
  • Effect of situational leadership theory training on head nurses’ leadership style in nursing management

    Objective To evaluate the effect of situational leadership theory training on head nurses’ leadership style in nursing management, and summarize the application methods of situational leadership theory. Methods In December 2013, by means of convenience cluster sampling method, 154 head nurses of West China Hospital of Sichuan University were selected for a Leadership Style Self-rating Questionnaire survey, of whom 84 attended the situational leadership theory training one month ago. The questionnaire score was compared between the trained head nurses (the trained group) and the non-trained ones (the non-trained group). Results A total of 154 questionnaires were issued, and 109 valid ones were recovered, in whom 72 were trained by the situational leadership theory while the other 37 were not. The average scores of head nurses’ flexibility and efficacy in the trained group (22.35±5.12 and 55.67±7.59) were higher than those in the non-trained group (19.03±4.05 and 50.95±5.30), and the proportions of head nurses with high flexibility and high efficacy in the trained group (61.1% and 31.9%) were higher than those in the non-trained group (32.4% and 8.1%), and the differences above were statistically significant (P<0.05). Conclusions The training of the situational leadership theory can improve the application of theory to clinical nursing management and promote the head nurses’ flexibility and efficacy to accelerate their work enthusiasm and personal improvement. It can also promote team cohesion and sense of accomplishment by creating a positive team atmosphere to make the efficient usage of limited human resources.

    Release date:2017-12-25 06:02 Export PDF Favorites Scan
  • Brain network theory, the significance and practice in clinical epileptology

    Currently, about one-third of patients with anti-epilepsy drug or resective surgery continue to have sezure, the mechanism remin unknown. Up to date, the main target for presurgical evaluation is to determene the EZ and SOZ. Since the early nineties of the last century network theory was introduct into neurology, provide new insights into understanding the onset, propagation and termination. Focal seizure can impact the function of whole brain, but the abnormal pattern is differet to generalized seizure. Brain network is a conception of mathematics. According to the epilepsy, network node and hub are related to the treatment. Graphy theory and connectivity are main algorithms. Understanding the mechanism of epilepsy deeply, since study the theory of epilepsy network, can improve the planning of surgery, resection epileptogenesis zone, seizure onset zone and abnormal node of hub simultaneously, increase the effect of resectiv surgery and predict the surgery outcome. Eventually, develop new drugs for correct the abnormal network and increase the effect. Nowadays, there are many algorithms for the brain network. Cooperative study by the clinicans and biophysicists instituted standard and extensively applied algorithms is the precondition of widely used clinically.

    Release date:2024-01-02 04:10 Export PDF Favorites Scan
  • Research on the change of Chinese health care integration policy from the perspective of advocacy coalition

    In the context of actively coping with aging, China has introduced a series of health care integration policies. Using the advocacy coalition framework theory, this paper aims to analyze the process of health care integration policy changes in China from three dimensions: policy beliefs, external events and policy learning. The policy subsystem of health care integration in China includes two coalitions: top-down cascade promotion and bottom-up absorption and radiation. External events and policy learning triggered policy change, where policy learning included endogenous learning within the coalition and exogenous learning between the coalitions. A policy impasse occurs when the two advocacy coalitions are at odds, and policy brokers and professional forums can get rid of the policy impasse. In the process of policy change in China’s health care integration, the two major advocacy coalitions have reached a certain consensus. It is recommended to alleviate the problems in the integration of health care by strengthening the external factors in the change of health care policy, enhancing the policy learning in the change of health care policy, and making full use of the information resources in the change of health care policy, so as to promote the high-quality development of the integration of health care.

    Release date:2022-01-27 09:35 Export PDF Favorites Scan
  • Analysis of Education Viewpoint of the University Based on the Education Theory

    Release date:2016-09-07 10:58 Export PDF Favorites Scan
  • Research progress of disrupted brain connectivity in mild cognitive impairment: findings from graph theoretical studies of whole brain networks

    Mild cognitive impairment (MCI) is a clinical transition state between age-related cognitive decline and dementia. Researchers can use neuroimaging and neurophysiological techniques to obtain structural and functional information about the human brain. Using this information researchers can construct the brain network based on complex network theory. The literature on graph theory shows that the large-scale brain network of MCI patient exhibits small-world property, which ranges intermediately between Alzheimer's disease and that in the normal control group. But brain connectivity of MCI patients presents topologically structural disorder. The disorder is significantly correlated to the cognitive functions. This article reviews the recent findings on brain connectivity of MCI patients from the perspective of multimodal data. Specifically, the article focuses on the graph theory evidences of the whole brain structural and functional and the joint covariance network disorders. At last, the article shows the limitations and future research directions in this field.

    Release date:2017-04-01 08:56 Export PDF Favorites Scan
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