At present, fatigue state monitoring of upper limb movement generally relies solely on surface electromyographic signal (sEMG) to identify and classify fatigue, resulting in unstable results and certain limitations. This paper introduces the sEMG signal recognition and motion capture technology into the fatigue state monitoring process and proposes a fatigue analysis method combining an improved EMG fatigue threshold algorithm and biomechanical analysis. In this study, the right upper limb load elbow flexion test was used to simultaneously collect the biceps brachii sEMG signal and upper limb motion capture data, and at the same time the Borg Fatigue Subjective and Self-awareness Scale were used to record the fatigue feelings of the subjects. Then, the fatigue analysis method combining the EMG fatigue threshold algorithm and the biomechanical analysis was combined with four single types: mean power frequency (MPF), spectral moments ratio (SMR), fuzzy approximate entropy (fApEn) and Lempel-Ziv complexity (LZC). The test results of the evaluation index fatigue evaluation method were compared. The test results show that the method in this paper has a recognition rate of 98.6% for the overall fatigue state and 97%, 100%, and 99% for the three states of ease, transition and fatigue, which are more advantageous than other methods. The research results of this paper prove that the method in this paper can effectively prevent secondary injury caused by overtraining during upper limb exercises, and is of great significance for fatigue monitoring.
ObjectiveTo observe the efficacy of intravitreal injection of conbercept (IVC) combined with subthreshold micropulse laser photocoagulation (SMLP) in the treatment of diabetic macular edema (DME). MethodsA randomized controlled trial. From December 2020 to January 2022, 100 patients (100 eyes) with DME diagnosed by examination in Shanxi Aier Eye Hospital were included in the study. The patients were randomly divided into IVC group (50 eyes) and IVC+SMLP group (50 eyes). All the eyes were treated with IVC once a month for 3 times, and the eyes in IVC+SMLP group were treated with SMLP within 2 weeks after IVC. All affected eyes were examined by best corrected visual acuity (BCVA), which was statistically converted to logarithm of the minimum angle of resolution (logMAR) visual acuity. The central macular thickness (CMT) was measured by optical coherence tomography. Before the treatment, the logMAR BCVA of patients in IVC group and IVC+SMLP group were 0.56±0.04 and 0.55±0.03, respectively. The CMT were (437.36±11.35) μm and (434.58±10.88) μm, respectively. There was no significant difference in logMAR BCVA and CMT between the two groups (t= 0.476, 1.027; P＞0.05). The patients were followed up for 12 months after treatment. The times of IVC and the changes of BCVA and CMT were compared between the two groups. Independent sample t-test was used to compare the logMAR BCVA, CMT and times of IVC between groups. ResultsAfter 12 months treatment, the logMAR BCVA of IVC group and IVC+SMLP group were (241.63±29.79) μm and (240.47±30.46) μm, respectively. Compared with those before treatment, 12 months after treatment, the BCVA of the two groups increased significantly (t=7.014, 5.608; P＜0.001), while CMT decreased significantly (t=8.126, 6.013; P＜0.001). There was no significant difference in BCVA and CMT between the two groups (t=0.835, 0.764; P＞0.05). The number of IVC in IVC group and IVC+SMLP group were (8.15±2.04) times and (5.91±1.80) times, respectively, and the difference was statistically significant (t=5.210, P＜0.001). ConclusionsBoth IVC+SMLP and IVC alone can effectively reduce CMT and increase BCVA in patients with DME. Combination therapy can reduce the number of IVC.
Abstract This experiment was to study the feasibility from direct observation of muscle contraction of the lower extremity fromelectrical stimulation threshold of nerve fascicle in identifying the Iα intrafusal afferent fibers during selective posterior rhizotomy (SPR) and to investigate the clinical relationship between the muscle spasm and the electrical stimulation of nerve fascicles. The electrical stimulation threshold of all nerve fascicles in 36 cases during SPR were analysed statistically. The results showed that there was a significant difference between the electrical stimulation threshold of the severed nerve fascicles and intact nerve fascicles no matter the nerve root or each posterior nerve rootlet was examined. It was simple and reliable for surgeons to identify correctly the Iα intrafusal afferent fibers intraoperatively from direct observation of the electrical stimulation threshold of nerve fascicle.
Central serous chorioretinopathy (CSC) is a common macular disease, mainly manifested as a plasma detachment of the macula. Photodynamic therapy (PDT) is an effective treatment for CSC, but with the shortage of the photosensitizer Verteporfin, the effective treatment of CSC has become a common concern for ophthalmologists. In this paper, based on the latest research results on the relationship between the changes in the thickness of the outer nuclear layer and the natural course of the disease and PDT therapy, we propose that patients with CSC should receive effective treatment as early as possible to prevent irreversible damage to visual function due to the thinning of the outer nuclear layer. In addition to PDT, it is recommended that laser photocoagulation or subthreshold micropulse laser treatment of the leaking spot should be considered first, depending on the presence of the leaking spot and its location in relation to the macula center. Anti-vascular endothelial growth factor therapy can be considered if there is a combination of choroidal neovascularization and/or polypoidal choroidal vasculopathy. Other treatments that have not been demonstrated to be effective in evidence-based medicine are not recommended.
Aiming at the single treatment and the design separation between treatment and assessment in electrotherapy equipment, a kind of system including low-intermediate frequency treatment and efficacy evaluation was developed. With C8051F020 single-chip microcomputer as the core and the circuit design and software programming used, the system realized the random switch of therapeutic parameters, the collection, display and data storage of pressure pain threshold in the assessment. Experiment results showed that the stimulus waveform, current intensity, frequency, duty ratio of the system output were adjustable, accurate and reliable. The obtained pressure pain threshold had a higher accuracy (<0.3 N) and better stability, guiding the parameter choice in the precise electrical stimulation. It, therefore, provides a reliable technical support for the treatment and curative effect assessment.
Spike recorded by multi-channel microelectrode array is very weak and susceptible to interference, whose noisy characteristic affects the accuracy of spike detection. Aiming at the independent white noise, correlation noise and colored noise in the process of spike detection, combining principal component analysis (PCA), wavelet analysis and adaptive time-frequency analysis, a new denoising method (PCWE) that combines PCA-wavelet (PCAW) and ensemble empirical mode decomposition is proposed. Firstly, the principal component was extracted and removed as correlation noise using PCA. Then the wavelet-threshold method was used to remove the independent white noise. Finally, EEMD was used to decompose the noise into the intrinsic modal function of each layer and remove the colored noise. The simulation results showed that PCWE can increase the signal-to-noise ratio by about 2.67 dB and decrease the standard deviation by about 0.4 μV, which apparently improved the accuracy of spike detection. The results of measured data showed that PCWE can increase the signal-to-noise ratio by about 1.33 dB and reduce the standard deviation by about 18.33 μV, which showed its good denoising performance. The results of this study suggests that PCWE can improve the reliability of spike signal and provide an accurate and effective spike denoising new method for the encoding and decoding of neural signal.
Objective To introduce the multivariate random effects model (MREM) in the meta-analysis of diagnostic tests with multiple thresholds. Methods This paper expanded and extended the bivariate random effects model (BREM) to develop the MREM, and implemented it in the SAS Proc NLMIXED procedure. Results The MREM could obtain the study specific ROC curve for each study through empirical Bayes estimation, and the summary ROC curve located in between all study specific ROC curves evenly, while the BREM couldn’t obtain the study specific ROC curve. In addition, in the aspect of parameters estimation, the MREM didn’t depend on the choice of the diagnosis threshold and the type of SROC. The MREM could get only one SROC curve and its AUC was between the AUC of the 5 types of SROC from BREM, so it could avoid overestimation or underestimation. Conclusion The MREM can fully exploit the data, obtain stable and reliable results, and have a good application value in meta-analysis of diagnostic tests with multiple thresholds.
This paper discusses the relationship between stimulating pulse width and the threshold of electrically evoked compound action potential (ECAP). Firstly, the rheobase and chronaxy from strength-duration curve of nerve fiber was computed using the shepherd's experiment results. Secondly, based on the relationship between ECAP and the action potential of nerve fiber, a mathematical expression to describe the relationship between stimulating pulse width and ECAP threshold was proposed. Thirdly, the parameters were obtained and the feasibility was proved to the expression with the results of experiment using guinea pigs. Research result showed that with ECAP compared to the action potential of nerve fiber, their threshold function relationship with stimulating pulse width was similar, and rheobase from the former was an order smaller in the magnitude than the latter, but the chronaxy was close to each other. These findings may provide meaningful guidance to clinical ECAP measurement and studying speech processing strategies of cochlear implant.
In the clinical evidence-based decision-making process, factors including benefits and harms, evidence certainty, cost and feasibility of interventions should be considered based on the best evidence. The development of decision threshold of effect size (DTES) for patient health outcomes can help stakeholders understand the benefits and harms of interventions, assess evidence certainty, and interpret research results. Based on international experience, the MERGE Working Group through group discussions, semi-structured interviews, expert consensus, and pilot application developed a set of 8-step guidelines for the development of DTES for health outcomes. These steps included necessity assessment, formation of working groups, selection of patient important outcomes, creation of scenarios based on the best evidence, design of expert consultation questionnaires, analysis of expert consultation results, face-to-face expert consensus, dissemination of the application and reevaluation. The DTES guideline development is intended to provide methodological guidance for stakeholders to develop DTES for health outcome indicators in different domains.
Objective Application of auditory brainstem response (ABR) in the study on the relationship of neonates with hypoxic-ischemic encephalopathy (HIE) and the children with hearing loss and auxiliary determine the prognosis of encephalopathy. Methods We prospectively selected neonates diagnosed as HIE in the department of neonatology of the Chengdu Women and Children Central Hospital from January, 2006 to June, 2008. Neonatal ABR was tested and the prognosis of neonates were observed through 3-year followed up in order to analyze the relationship between HIE severity and the severity of hearing handicap and the relationship between the severity of hearing handicap and prognosis. Statistical analysis was performed using SPSS 18.0. χ2 test was used to compare the rate between groups. Results 40 cases involving 80 ears were included, of which 33 cases accomplished the 3-year follow-up for prognosis. The results showed that, 86.3% HIE neonates had hearing handicap (mainly mild hearing loss, 40.0%). Medium-severe HIE groups had more serious hearing handicap than Mild HIE group with a statistical significance (continuity correction χ2=7.383, P=0.007). ABR results showed that, mild HIE is mainly manifested as I wave PL prolonged or poorly differentiated, accounting for 78.1%; medium - severe HIE are mainly manifested as III and V wave PL prolonged central segment abnormalities, accounting for 95.8%; the hearing threshold no more than 60 dB group had better prognosis than the hearing threshold more than 60 dB group prognosis (Fisher exact probability P=0.001). Conclusion ABR reflects that HIE severity and was positively related to the severity of hearing handicap. The more serious hearing loss in neonates is, the worse prognosis the neonates have. ABR can be used to assist the assessment of the prognosis of neonatal HIE.
