The automatic classification of epileptic electroencephalogram (EEG) is significant in the diagnosis and therapy of epilepsy. A classification algorithm for epileptic EEG based on wavelet multiscale analysis and extreme learning machine (ELM) is proposed in this paper. Firstly, wavelet multiscale analysis is applied to the original EEG to extract its sub-bands. Then, two nonlinear methods, i.e. Hurst exponent (Hurst) and sample entropy (SamEn) are used to the feature extraction of EEG and its sub-bands. Finally, ELM algorithm is employed in epileptic EEG classification with the nonlinear features. The proposed method in this paper achieved 99.5% classification accuracy for the discrimination between epileptic ictal and interictal EEG. The result implies that this method has good prospects in the diagnosis and therapy of epilepsy.
ObjectiveTo study the preservation effect of true bone ceramics (TBC) prepared by high-temperature calcination of bovine bone on alveolar ridge of canine extraction socket.MethodsSix healthy Beagle dogs (aged 1.5-2 years) were selected to extract the second and fourth premolars of both mandibles and the second premolars of the maxilla. The left extraction socket was implanted with TBC as the experimental group, and the right side was implanted with the calcined bovine bone (CBB) as the control group, to observe the alveolar ridge preservation effect. Three dogs were euthanized after general observation at 1 and 6 months after operation respectively. After separating the maxilla and mandible, cone beam CT (CBCT) was performed to measure the average gray value of the graft site and the adjacent reference area (the area between the roots of the adjacent third premolar) and calculate the gray scale ratio between the bone graft site and the reference area. Histological observation was made on the bone graft site to evaluate the new bone formation.ResultsGeneral observation showed that the wounds of both groups were basically healed at 2 weeks after operation, and the bone graft materials were not exposed. The wounds healed well at 1 and 6 months after operation without swelling. The results of CBCT showed that the residual material was found in both groups at 1 month after operation, and no significant residual material was found in both groups at 6 months after operation, and the alveolar ridge height of the bone graft area was not significantly reduced. There was no significant difference in the bone mineral density between the experimental group and the control group. The gray scale ratios of the experimental group at 1 month and 6 months after operation were 0.97±0.14 and 0.93±0.06, respectively, and were 0.99±0.16 and 0.94±0.05 in control group, showing no significant difference between the two groups (t=?1.030, P=0.333; t=?0.770, P=0.466). HE staining observation showed that a large number of bone graft materials did not degrade and new bone formed around the grafts in both groups at 1 month after operation; the bone graft materials were absorbed and a large number of new bones were formed in both groups at 6 months after operation.ConclusionTBC can maintain bone mineral density and have good osteoconductivity in the alveolar ridge site preservation experiment of dogs, and can be used for alveolar ridge site preservation.
The electroencephalogram (EEG) has proved to be a valuable tool in the study of comprehensive conditions whose effects are manifest in the electrical brain activity, and epilepsy is one of such conditions. In the study, multi-scale permutation entropy (MPE) was proposed to describe dynamical characteristics of EEG recordings from epilepsy and healthy subjects, then all the characteristic parameters were forwarded into a support vector machine (SVM) for classification. The classification accuracies of the MPE with SVM were evaluated by a series of experiments. It is indicated that the dynamical characteristics of EEG data with MPE could identify the differences among healthy, inter-ictal and ictal states, and there was a reduction of MPE of EEG from the healthy and inter-ictal state to the ictal state. Experimental results demonstrated that average classification accuracy was 100% by using the MPE as a feature to characterize the healthy and seizure, while 99.58% accuracy was obtained to distinguish the seizure-free and seizure EEG. In addition, the single-scale permutation entropy (PE) at scales 1-5 was put into the SVM for classification at the same time for comparative analysis. The simulation results demonstrated that the proposed method could be a very powerful algorithm for seizure prediction and could have much better performance than the methods based on single scale PE.
Interventional micro-axial flow blood pump is widely used as an effective treatment for patients with cardiogenic shock. Hemolysis and coagulation are vital concerns in the clinical application of interventional micro-axial flow pumps. This paper reviewed hemolysis and coagulation models for micro-axial flow blood pumps. Firstly, the structural characteristics of commercial interventional micro-axial flow blood pumps and issues related to clinical applications were introduced. Then the basic mechanisms of hemolysis and coagulation were used to study the factors affecting erythrocyte damage and platelet activation in interventional micro-axial flow blood pumps, focusing on the current models of hemolysis and coagulation on different scales (macroscopic, mesoscopic, and microscopic). Since models at different scales have different perspectives on the study of hemolysis and coagulation, a comprehensive analysis combined with multi-scale models is required to fully consider the influence of complex factors of interventional pumps on hemolysis and coagulation.
Objective To develop an innovative recognition algorithm that aids physicians in the identification of pulmonary nodules. MethodsPatients with pulmonary nodules who underwent thoracoscopic surgery at the Department of Thoracic Surgery, Affiliated Drum Tower Hospital of Nanjing University Medical School in December 2023, were enrolled in the study. Chest surface exploration data were collected at a rate of 60 frames per second and a resolution of 1 920×1 080. Frame images were saved at regular intervals for subsequent block processing. An algorithm database for lung nodule recognition was developed using the collected data. ResultsA total of 16 patients were enrolled, including 9 males and 7 females, with an average age of (54.9±14.9) years. In the optimized multi-topology convolutional network model, the test results demonstrated an accuracy rate of 94.39% for recognition tasks. Furthermore, the integration of micro-variation amplification technology into the convolutional network model enhanced the accuracy of lung nodule identification to 96.90%. A comprehensive evaluation of the performance of these two models yielded an overall recognition accuracy of 95.59%. Based on these findings, we conclude that the proposed network model is well-suited for the task of lung nodule recognition, with the convolutional network incorporating micro-variation amplification technology exhibiting superior accuracy. Conclusion Compared to traditional methods, our proposed technique significantly enhances the accuracy of lung nodule identification and localization, aiding surgeons in locating lung nodules during thoracoscopic surgery.
Deep learning-based automatic classification of diabetic retinopathy (DR) helps to enhance the accuracy and efficiency of auxiliary diagnosis. This paper presents an improved residual network model for classifying DR into five different severity levels. First, the convolution in the first layer of the residual network was replaced with three smaller convolutions to reduce the computational load of the network. Second, to address the issue of inaccurate classification due to minimal differences between different severity levels, a mixed attention mechanism was introduced to make the model focus more on the crucial features of the lesions. Finally, to better extract the morphological features of the lesions in DR images, cross-layer fusion convolutions were used instead of the conventional residual structure. To validate the effectiveness of the improved model, it was applied to the Kaggle Blindness Detection competition dataset APTOS2019. The experimental results demonstrated that the proposed model achieved a classification accuracy of 97.75% and a Kappa value of 0.971 7 for the five DR severity levels. Compared to some existing models, this approach shows significant advantages in classification accuracy and performance.
Objective To study the characteristics of pulmonary impact injury under closure and open states of glottis. Methods One hundred and eight rabbits were randomly divided into two groups (54 each group). Open state of glottis group(open group): impact injuries with opened glottis; closure state of glottis group (closed group): impact injuries with closed glottis. Parameters were set up with various combinations of driven pressures and compress percentage and the model of rabbit blunt chest trauma were established. Pathological changes were examined and abbreviated injury scale (AIS), water containing and mortality were recorded. Results Two and four rabbits died in open group and closed group respectively under the condition of 30% for compress percentage and 8 250 mmHg for driven pressures. In most cases, AIS values of closed group were significantly higher than that of open group (Plt;0.05). AIS values were positively related to driven pressures and compress percentage (r=0.9313, 0.7847; Plt;0.01, 0.01). Quantities of contained water in lung of closed group were significantly higher than that of open group(t=2.28,Plt;0.01). Conclusion The severity of injury, the increased mortality and earlier occurrence of traumatic acute lung injury were the characteristics of pulmonary impact injury under the closure states of glottis.
Objective To observe the serumlevel of neuron-specific enolase( NSE) in patients with pulmonary encephalopathy and its changes after treatment with mechanical ventilation. Methods Twentyone patients with pulmonary encephalopathy were enrolled. Glasgow coma scale( GCS) , serumNSE level, and arterial blood gas were evaluated at three time-points: before mechanical ventilation, after 12 hours mechanical ventilation, and the moment of consciousness. Results 18 patients recovered consciousness, and 3 patients remained in persistent coma and died. GCS and arterial blood gas improved obviously after 12 hours mechanical ventilation. Meanwhile, the serumNSE concentration decreased significantly after 12 hours mechanical ventilation [ ( 24. 54 ±6. 65) μg/L] and at the moment of consciousness [ ( 14. 19 ±2. 91) μg/L] compared with before mechanical ventilation( P lt; 0. 05, P lt; 0. 01) . Conclusion Dynamic measurment of serumNSE may be a useful biomarker for assessing the severity of cerebral injury and predicting prognosis.
ObjectiveTo measure the operational efficiency and explore the phenomenon of the economy of scale in secondary public general hospitals of China for improving the health service efficiency.MethodsFrom February to August 2019, the data set of two input indicators (the number of employees and actual open beds) and two output indicators (the numbers of outpatients and discharges) in 511 secondary general hospitals of Shandong, Anhui, Shanxi, Hubei and Hainan provinces in 2018 were collected for data envelopment analysis. The analysis processes were three folds: First, the technical efficiency, pure technical efficiency, scale efficiency and scale compensation status of the sample hospitals were calculated respectively. Second, the comparative analysis of efficiency value and scale compensation status was carried out in 5 groups according to the bed scale. Finally, the input and output projection analysis was carried out on the ineffective decision making units.ResultsThe medians of technical efficiencies, pure technical efficiencies, and scale efficiencies of the 511 secondary general hospitals were 0.472, 0.531, and 0.909, respectively. In the 511 hospitals, 493 hospitals (96.5%) were in ineffective state, of which 321 hospitals (62.8%) were in the state of decreasing return to scale. The staff redundancy of the group with beds >100 and ≤300 was 23.86%, and its service quantity could be increased by 39.37%.ConclusionsThe overall operating efficiencies are inefficiency in secondary general hospitals of China and the optimal scale of actual open beds is between 300 and 500 beds from the perspective of scale efficiency.
ObjectiveTo investigate the feasibility and effect of early pulmonary rehabilitation (PR) in patients after acute exacerbation of chronic obstructive pulmonary disease (COPD) in a district hospital. MethodsA single-centre prospective study was conducted. The COPD patients after an episode of acute exacerbation and referred to the outpatient department were recruited from January 2013 to December 2014. They were randomized to a group with PR (PR group) and a group without PR (wPR group). The following data were recorded and evaluated including age, gender, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and FEV1 as a percentage of the predicted value (FEV1% pred).The baseline and the post-PR medical research council scale (MRC), St. George's respiratory questionnaire (SGRQ), and six-minute walk distance (6MWD) were also compared. ResultsA total of 91 cases were enrolled with 46 cases in the PR group and 45 cases in the wPR group. The age, gender, the severity of COPD were similar in two groups (P > 0.05). The MRC score and SGRQ score of the PR group were significantly improved 3 months later compare with the baseline (P < 0.05), and did not changed significantly in the wPR group (P > 0.05). There were 26 patients whose SGRQ scores decreased > 4 in the PR group (26/46, 56.5%), which was significantly higher than the wPR group (7/45, 15.6%) (P < 0.05). The 6MWD of the PR group was significantly increased 3 months later compare with the baseline (P < 0.05), and did not changed significantly in the wPR group (P > 0.05). There were 22 patients whose 6MWD increased > 54 meters in the PR group (22/46, 47.8%), which was significantly higher than the wPR group (9/45, 20.0%) (P < 0.05). ConclusionsIt is feasible and safety to perform early PR in patients after acute exacerbation of COPD in the district hospital. The early PR can improve the MRC score, SGQR score, and 6MWD in COPD patients.