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find Keyword "sensor" 45 results
  • Study on a New Urine Analysis Core Module Based on Semi-reflection Mirror

    A new urine analysis core module based on high performance 32-bit microprocessor and high precision color sensor was presented. A novel optical structure and a specific circuit were applied to improve measurement precision and temperature was used to compensate for results in this core module. The information of urine test peice, such as all original data and color RGB value, reflectivity, semi-quantitative level, etc. can be output. The results showed that the measuring precision was about 95% or above with ideal stability and reliability using this presented core module, which can be conveniently applied in various urine analyzers, and can greatly decrease the cost of urine analyzers in development and production.

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  • Quantitative assessment of stroke patients based on dynamic time warping algorithm

    In order to accurately evaluate the similarity of motions during daily rehabilitation training for stroke patients, this paper proposed a novel quantitative assessment method based on dynamic time warping (DTW) algorithm. Firstly, the raw accelerometer signals were preprocessed to eliminate the noise. Secondly, the similarity between the accelerometer signals and four standard task templates was calculated respectively, and then the motion was recognized based on the similarity measurements. Finally, the corresponding quantitative assessment model was used to compute the result. The clinical experimental results showed that there were significant differences in the shortest path distance (R value) of DTW between different tasks, and the classification accuracy could be up to 91% when the R value was selected as the classification feature. Additionally, with the process of rehabilitation, the R value decreased gradually, which means that the R value can be taken as the assessment index to evaluate the quality of designated tasks for stroke patients. It also indicated that the R value could be applied into the scene of automatic prescription generation and interactive gaming to determine whether it is needed to change the rehabilitation plan or adjust the game difficulty level, so as to implement the individualized rehabilitation services.

    Release date:2018-02-26 09:34 Export PDF Favorites Scan
  • Application of exhaled breath analysis using a graphene sensor array for lung cancer screening and diagnosis: A prospective cohort study of 4 580 patients

    Objective To explore a novel method for early lung cancer screening based on exhaled breath analysis. MethodsThis study enrolled patients with suspected pulmonary malignancies and healthy individuals undergoing physical examinations at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine (Qingchun and Qiantang campuses) from September 2023 to June 2024. Enrolled subjects were categorized into a lung cancer group, a benign nodule/tumor group, and a healthy control group. Exhaled breath samples were collected using a sensor array constructed from multiple graphene composite materials to capture breath fingerprints. Based on the collected data, screening and diagnostic models for lung cancer were developed and their performance was evaluated. ResultsA total of 4 580 subjects were included. Among them, 3 195 were pathologically diagnosed with pulmonary malignancies, including 1 394 males and 1 801 females with a mean age of (58.93±12.37) years, 599 were diagnosed with benign nodules/tumors including 339 males and 260 females with a mean age of (57.10±11.06) years, and 786 were healthy controls with no pulmonary nodules detected on chest CT including 420 males and 366 females with a mean age of (29.75±9.32) years. The screening model for high-risk populations (distinguishing patients with lung cancer/high-risk pulmonary nodules from healthy individuals) demonstrated excellent performance, with an area under the receiver operating characteristic curve (AUC) of 0.926. At the optimal Youden’s index (cutoff threshold of 63.5%), the external test set achieved a specificity of 85.2%, a sensitivity of 88.4%, and an accuracy of 86.8%. The diagnostic model (distinguishing patients with lung cancer/premalignant lesions from those with benign pulmonary nodules/healthy individuals) achieved an AUC of 0.818. At its optimal Youden’s index (cutoff threshold of 47.0%), the external test set showed a specificity of 71.7%, a sensitivity of 77.3%, and an accuracy of 74.5%. ConclusionThe non-invasive breath analysis platform based on a sensor array, developed in this study, can achieve rapid and relatively accurate lung cancer screening by analyzing breath fingerprints. This confirms the feasibility of this technology for early lung cancer screening and holds promise for facilitating the early detection and intervention of lung cancer.

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  • Research progress on the related mechanisms of facial complex regional pain syndrome

    Facial complex regional pain syndrome (CRPS) is a CRPS that occurs around the periorbital and/or orofacial region, showing regional chronic pain accompanied by motor and autonomic nervous dysfunction. At present, the pathogenesis of CRPS is not clear, which may include inflammatory reaction, sympathetic nerve, spinal cord, supraspinal and other mechanisms. It is related to the hemisensory disturbances of CRPS, and closely associated with facial allodynia and migraine with trigeminal nerve. This article reviews the possible mechanisms of facial CRPS and connects the limb pain with facial pain, in order to provide some reference for the study of the pathogenesis of CRPS.

    Release date:2022-06-27 09:55 Export PDF Favorites Scan
  • Structure design of a new video laryngoscope image sensor

    In order to overcome the influence of stray light and impurity on the image of video laryngoscope, we designed an optical structure by using TracePro, a simulation software, to imitate optical path status. Images are captured by CMOS sensor which has the size of 4.5 mm×18 mm and the pixel size is 1.75 μm×1.75 μm. The sensor is placed in the elbow of the laryngoscope, and the elbow has the size of 9 mm×10 mm. As a result, the video laryngoscope could meet the requirements, including wide viewing angle (80°), short focal length (2.8 mm), long working distance (10 cm), and least impurity. In the test, the image was clear and there was no facula or impurity in the condition of required illumination, and thus stray light and image impurity were eliminated and the image quality was improved.

    Release date:2017-04-01 08:56 Export PDF Favorites Scan
  • Research on feature classification of lower limb motion imagination based on electrical stimulation to enhance rehabilitation

    Motor imaging therapy is of great significance to the rehabilitation of patients with stroke or motor dysfunction, but there are few studies on lower limb motor imagination. When electrical stimulation is applied to the posterior tibial nerve of the ankle, the steady-state somatosensory evoked potentials (SSSEP) can be induced at the electrical stimulation frequency. In order to better realize the classification of lower extremity motor imagination, improve the classification effect, and enrich the instruction set of lower extremity motor imagination, this paper designs two experimental paradigms: Motor imaging (MI) paradigm and Hybrid paradigm. The Hybrid paradigm contains electrical stimulation assistance. Ten healthy college students were recruited to complete the unilateral movement imagination task of left and right foot in two paradigms. Through time-frequency analysis and classification accuracy analysis, it is found that compared with MI paradigm, Hybrid paradigm could get obvious SSSEP and ERD features. The average classification accuracy of subjects in the Hybrid paradigm was 78.61%, which was obviously higher than the MI paradigm. It proves that electrical stimulation has a positive role in promoting the classification training of lower limb motor imagination.

    Release date:2021-08-16 04:59 Export PDF Favorites Scan
  • Vasodilators for sudden sensorinenral hearing loss:a systematicreview of randomized controlled trials

    Objective To assess the effects and safety of vasodilators for sudden sensorineurial hearing loss (SSHL). Search strategy Electronic databases: MEDLINE from 1966, EMBASE from 1974, the Cochrane Controlled Trials Register, Chinese Bio-medicine Database from 1989. Hand search: Five kinds of Chinese otolaryngology journals were searched. Literature references were checked intensively. Selection criteria Randomized controlled trials comparing vasodilators with placebo or other drugs in patients with SSHL. Data collection and analysis At least two reviewers independently assessed trials quality and extracted data. Main results Thirteen trials with 1 155 patients were eligible and included in the systematic review. Ten of the trials were from developed countries and them were from P. R. China. None of the four trials showed that the effects of vasodilators were better than placebo for SSHL. None of the seven trials showed that the effects of one kind of vasodilators were better than that of the other vasodilators. Two trials showed that other drugs, such as batroxobin and hypaque,were probably better than some vasodilators (dextran, papaverine, 654-2, danshen). Eight trials reported the side effects of vasodilators, such as pruritus, allergy, etc. Reviewers’ conclusions Base on the systematic review of current eligible randomized controlled trials, there is no evidence to prove that vasodilator therapy is better than placebo or other therapies for SSHL, or the effects of one kind of vasodilator are better than that of the other vasodilators. We can’t draw a reliable conclusion about the effects of vasodilators for SSHL at the moment. And we must pay attention to their potential adverse reactions.

    Release date:2016-08-25 03:16 Export PDF Favorites Scan
  • Design and implementation of ratiometric fluorescence detection system for serum bilirubin

    The current quantitative methods of bilirubin have disadvantages such as high cost and low sensitivity. Due to the negative correlation between the level of serum bilirubin and the risk of cardiovascular diseases, a fluorescent ratiometric film sensor was developed aiming at bilirubin detection at low level concentration. Blue-emitting and red-emitting gold nanoclusters were assembled into the same film using layer-by-layer self-assembly technology. Detection of bilirubin was achieved based on the intensity ratio of the two nanoclusters. Bilirubin exposure causes fluorescent quenching of the film. The fluorescence intensity ratio of the two cluster probes had quantitative relationship versus bilirubin concentration. Based on this film sensor, a portable fluorescence detection system was designed for the ratiometric sensing of bilirubin. The hardware of the system was mainly composed of main control chip STM32F407, TSL237 and TSL238T optical frequency sensor. A light-avoiding dark room and detection light path were designed through three-dimensional printing to reduce the interference from ambient light and improve detection accuracy. Experimental results showed that the proposed detection system had strong anti-interference, good stability and accuracy. The linear coefficient of bilirubin detected by this system was 0.987. The system presented good results in reproducible experiments and possessed a good linear relationship with the data obtained by standard spectrofluorometer. The portable system is expected to detect serum bilirubin at low levels.

    Release date:2022-10-25 01:09 Export PDF Favorites Scan
  • Research status and prospect of mandibular sensory dysfunction after transoral endoscopic thyroidectomy vestibular approach

    ObjectiveTo summarize the research status of mandibular sensory dysfunction after transoral endoscopic thyroidectomy vestibular approach (TOETVA), and explore its potential treatment methods and existing problems, and provide ideas and methods for future clinical treatments or research. MethodThe domestic and foreign literatures about peripheral nerve injury and its treatment after TOETVA were searched and reviewed. ResultsMental nerve injury was considered to be the main cause of mandibular sensory dysfunction after TOETVA. Due to the lack of unified definitions and assessment standards, the true incidence remained unclear. In order to reduce the risk of mental nerve injury, methods such as exposing the mental nerve and combining vestibular approaches during surgery had certain advantages. In terms of treatment, several methods promoting nerve repair were noteworthy, including B vitamins, nerve growth factors, physical therapy and so on. In addition, some auxiliary treatments of Traditional Chinese Medicine also showed effectiveness in promoting nerve regeneration. ConclusionsIt is essential to avoid damage to the mental nerve and mandibular tissues during surgery. For patients with significant complaints postoperatively, active treatment should be pursued. Establishing objective and quantifiable standards for evaluating mandibular sensory dysfunction and seeking effective clinical plans through a multidisciplinary approach may be the direction for future research.

    Release date:2024-09-25 04:19 Export PDF Favorites Scan
  • Development of flexible multi-phase barium titanate piezoelectric sensor for physiological health and action behavior monitoring

    Self-powered wearable piezoelectric sensing devices demand flexibility and high voltage electrical properties to meet personalized health and safety management needs. Aiming at the characteristics of piezoceramics with high piezoelectricity and low flexibility, this study designs a high-performance piezoelectric sensor based on multi-phase barium titanate (BTO) flexible piezoceramic film, namely multi-phase BTO sensor. The substrate-less self-supported multi-phase BTO films had excellent flexibility and could be bent 180° at a thickness of 33 μm, and exhibited good bending fatigue resistance in 1 × 104 bending cycles at a thickness of 5 μm. The prepared multi-phase BTO sensor could maintain good piezoelectric stability after 1.2 × 104 piezoelectric cycle tests. Based on the flexibility, high piezoelectricity, wearability, portability and battery-free self-powered characteristics of this sensor, the developed smart mask could monitor the respiratory signals of different frequencies and amplitudes in real time. In addition, by mounting the sensor on the hand or shoulder, different gestures and arm movements could also be detected. In summary, the multi-phase BTO sensor developed in this paper is expected to develop convenient and efficient wearable sensing devices for physiological health and behavioral activity monitoring applications.

    Release date:2024-06-21 05:13 Export PDF Favorites Scan
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