Development of wearable posture monitoring system for dynamic assessment of sitting posture.

There have been increasing cases of people seeking treatment for neck and back pain. The most common cause of neck and back pain is due to long-term poor sitting posture. The most common poor sitting posture cases are humpback, and head and neck being too far forward. It is easy to cause neck and back pain and other symptoms. Therefore, the development of wearable posture monitoring system for dynamic assessment of sitting posture becomes both helpful and necessary. In addition to recording the wearer's posture when sitting with quantitative assessment, it is needed to execute real-time action feedback for correctness of posture, in order to reduce neck and back pain due to long-term poor sitting posture. This study completed an instant recording and dynamic assessment of position measurement and feedback system. The system consists of a number of dynamic measurement units that can describe the posture trajectory, which integrates three-axis gyro meter, three-axis accelerometer, and magnetometer in order to measure the dynamic tracking. In the reliability analysis experiment, angle measurement error is less than 2%. The correlation coefficient between correlation analysis and Motion Analysis (MA) is 0.97. It is shown that the motion trajectory of this system is highly correlated with MA. In the feasibility test of sitting position detection, it is possible to detect the sitting position from the basic action of the walking, standing, sitting and lying down, and the sensitivity reaches 95.84%. In the assessment of the sitting position, the information published by the Canadian Centre for Occupational Health and Safety was used, as well as the recommendations of professional physicians as a basis for evaluating the threshold of the sitting measurement parameters and immediately feedback to the subjects. The system developed in this study can be helpful to reduce neck and back pain due to long-term poor sitting posture.

Radiomics features analysis of PET images in oropharyngeal and hypopharyngeal cancer.

This study used radiomics image analysis to examine the differences of texture feature values extracted from oropharyngeal and hypopharyngeal cancer positron emission tomography (PET) images on various tumor segmentations, and finds the proper and stable feature groups. A total of 80 oropharyngeal and hypopharyngeal cancer cases were retrospectively recruited. Radiomics method was applied to the PET image for the 80 oropharyngeal and hypopharyngeal cancer cases to extract texture features from various defined metabolic volumes. Kruskal-Wallis one-way analysis of variance method was used to test whether feature value difference exists between groups, which were grouped by stage, response to treatment, and recurrence. If there was a significant difference, the corresponding feature cutoff value was applied to the Kaplan-Meier estimator to estimate the survival functions. For the various defined metabolic volumes, there were 16 features that had significant differences between early (T1, T2) and late tumor stages (T3, T4). Five images and 2 textural features were found to be able to predict the tumor response and recurrence, respectively, with the areas under the receiver operating characteristic curves reaching 0.7. The histogram entropy was found to be a good predictor of overall survival (OS) and primary relapse-free survival (PRFS) of oropharyngeal and hypopharyngeal cancer patients. Textural features from PET images provide predictive and prognostic information in tumor staging, tumor response, recurrence, and have the potential to be a prognosticator for OS and PRFS in oropharyngeal and hypopharyngeal cancer.

Acoustic features for identifying constitutions in traditional Chinese medicine.

OBJECTIVES: Constitutions are Traditional Chinese Medicine syndromes that are used to classify symptoms. The present study sought to identify objective acoustic features for eight commonly occurring abnormal constitutions. METHODS: Speech signals were obtained from 281 subjects through a 1-second vowel sound, /a/, uttered by the subjects. For each constitution, differences in acoustic parameters between the low-score and high-score groups were compared. RESULTS: Subjects in the high-score groups for Yin-deficiency, Qi-deficiency, Phlegm-wet, Blood-stasis, and Qi-depression showed lower acoustic intensities than subjects in the corresponding low-score groups (all p<0.05). Subjects in the high-score groups of Qi-deficiency and Blood-stasis exhibited higher maximum pitches and higher minimum pitches than subjects in the low-score groups (all p<0.01). The average number of zero-crossings was lower in the high-score groups of Qi-deficiency and Blood-stasis than in the low-score groups for both constitutions (p<0.05). Subjects in the high-score group of special diathesis demonstrated higher low-spectral-energy ratios than subjects in the low-score group (p<0.05), and subjects in the high-score group of Blood-stasis had higher middle spectral energy ratios than subjects in the low-score group (p<0.05). In contrast, the middle spectral energy ratio in the high-score group of special diathesis was lower than in its corresponding low-score group (p<0.05). The high spectral energy ratios were lower in the high-score groups for Yin-deficiency and Blood-stasis (both p<0.05) than in the low-score groups. CONCLUSIONS: The present study identified acoustic features for constitutions and established objective methods for constitutional diagnosis. These acoustic features can potentially be applied in the expert system of Traditional Chinese Medicine for the diagnosis of constitutions in the general population.

Dynamic cerebral autoregulation assessment using chaotic analysis in diabetic autonomic neuropathy.

Cerebral autoregulation (CA) was assessed by chaotic analysis based on mean arterial blood pressure (MABP) and mean cerebral blood flow velocity (MCBFV) in 19 diabetics with autonomic neuropathy (AN) and 11 age-matched normal subjects. MABP in diabetics dropped significantly in response to tilting (91.6 +/- 14.9 vs. 74.1 +/- 13.4 mmHg, P < 0.05). Valsalva ratio of heart rate was reduced in diabetics compared to normal (1.1 +/- 0.1 vs. 1.5 +/- 0.2, P < 0.05). It indicated AN affects the vasomotor tone of peripheral vessels and baroreflex. Nonlinear results showed higher correlation dimension values of MABP and MCBFV in diabetics compared to normal, especially MABP (3.7 +/- 2.3 vs. 2.0 +/- 0.8, P < 0.05). It indicated CA is more complicated in diabetics. The lower Lyapunov exponent and the higher Kolmogorov entropy values in diabetics indicated less predictable behavior and higher chaotic degree. This study suggests impaired autoregulation would be more chaotic and less predictable.

Objective assessment of blood stasis using computerized inspection of sublingual veins.

In traditional Chinese tongue diagnosis, inspection of the sublingual veins has been developed as a new diagnostic examination method especially for determining blood stasis. The main purpose of this research is to develop a computerized inspection system, used to quantitatively extract the chromatic and geometrical properties of sublingual veins. A method based on color equalization is presented to assist the image segmentation of sublingual veins. Color image analysis techniques are applied to extract the length, width, area and color information from sublingual veins. Experimental results are compared with the visual inspection of physicians. The severity of blood stasis was classified into three groups: normal, moderate and pronounced. Each group consisted of eight subjects. The overall recognition rate is 87.5% in the leaving-one-out classification using the developed system.