Browsing by Author "Gao X"

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    A Semi-automatic Diagnosis of Hip Dysplasia on X-Ray Films
    (Frontiers Media S.A., 2020-12-17) Yang G; Jiang Y; Liu T; Zhao X; Chang X; Qiu Z; Gao X
    Background: Diagnosis of hip joint plays an important role in early screening of hip diseases such as coxarthritis, heterotopic ossification, osteonecrosis of the femoral head, etc. Early detection of hip dysplasia on X-ray films may probably conduce to early treatment of patients, which can help to cure patients or relieve their pain as much as possible. There has been no method or tool for automatic diagnosis of hip dysplasia till now. Results: A semi-automatic method for diagnosis of hip dysplasia is proposed. Considering the complexity of medical imaging, the contour of acetabulum, femoral head, and the upper side of thigh-bone are manually marked. Feature points are extracted according to marked contours. Traditional knowledge-driven diagnostic criteria is abandoned. Instead, a data-driven diagnostic model for hip dysplasia is presented. Angles including CE, sharp, and Tonnis angle which are commonly measured in clinical diagnosis, are automatically obtained. Samples, each of which consists of these three angle values, are used for clustering according to their densities in a descending order. A three-dimensional normal distribution derived from the cluster is built and regarded as the parametric model for diagnosis of hip dysplasia. Experiments on 143 X-ray films including 286 samples (i.e., 143 left and 143 right hip joints) demonstrate the effectiveness of our method. According to the method, a computer-aided diagnosis tool is developed for the convenience of clinicians, which can be downloaded at http://www.bio-nefu.com/HIPindex/. The data used to support the findings of this study are available from the corresponding authors upon request. Conclusions: This data-driven method provides a more objective measurement of the angles. Besides, it provides a new criterion for diagnosis of hip dysplasia other than doctors' experience deriving from knowledge-driven clinical manual, which actually corresponds to very different way for clinical diagnosis of hip dysplasia.
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    Psychometric validation of the sibling inventory of behavior in three- to six-year-old Chinese children.
    (Frontiers Media S.A., 2023-03-06) Xu H; Wang Z; Gao X; Wang X; Wu Q; Osman A
    With increasing attention on sibling relationship studies in China, one problem that has been neglected is the limited validation of instruments used to assess these relationships. The present study evaluated the psychometric properties of the Sibling Inventory of Behavior to measure Chinese children’s sibling relationships using a stratified random sample of 590 parents of three- to six-year-olds in three economic regions. The confirmatory factor analysis obtained an adequate fit, suggesting that the Chinese version of the instrument had a six-factor structure (i.e., Companionship, Empathy, Teaching, Rivalry, Aggression, and Avoidance). It demonstrated satisfactory internal consistency as well as test–retest reliability. Results of discriminant, convergent, and criterion-related validity test also fulfilled psychometric requirements. Furthermore, the residual measurement invariance across regions was discovered. Given the importance, emergence, and tendency of sibling studies in China, having a reliable and valid instrument with robust psychometric properties is essential and impactful.
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    Seasonal variation in soil and herbage CO2 efflux for a sheep-grazed alpine meadow on the north-east Qinghai-Tibetan Plateau and estimated net annual CO2 exchange
    (2/06/2022) Yuan H; Matthew C; He XZ; Sun Y; Liu Y; Zhang T; Gao X; Yan C; Chang S; Hou F
    The Qinghai-Tibetan Plateau is a vast geographic area currently subject to climate warming. Improved knowledge of the CO2 respiration dynamics of the Plateau alpine meadows and of the impact of grazing on CO2 fluxes is highly desirable. Such information will assist land use planning. We measured soil and vegetation CO2 efflux of alpine meadows using a closed chamber technique over diurnal cycles in winter, spring and summer. The annual, combined soil and plant respiration on ungrazed plots was 28.0 t CO2 ha-1 a-1, of which 3.7 t ha-1 a-1occurred in winter, when plant respiration was undetectable. This suggests winter respiration was driven mainly by microbial oxidation of soil organic matter. The winter respiration observed in this study was sufficient to offset the growing season CO2 sink reported for similar alpine meadows in other studies. Grazing increased herbage respiration in summer, presumably through stimulation of gross photosynthesis. From limited herbage production data, we estimate the sustainable yield of these meadows for grazing purposes to be about 500 kg herbage dry matter ha-1 a-1. Addition of photosynthesis data and understanding of factors affecting soil carbon sequestration to more precisely determine the CO2 balance of these grasslands is recommended.
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    Under the same roof: Parents’ COVID-related stress mediates the associations between household crowdedness and young children’s problem behaviors during social distancing.
    (Elsevier B.V., 2021) Wang Z; Yeung PL; Gao X
    During the COVID-19 pandemic, families worldwide are confined in their homes for an extended period of time due to social distancing. Conducted between April and July of 2021, the current study examined the impact of household crowdedness during school closure on parents’ COVID-related stress and young children's problem behaviors in Hong Kong, one of the world's most densely populated cities. Parents of 228 young children between 3- to 5-year-old reported their household living condition, parents’ COVID-related stress, and their children's externalizing and internalizing behaviors through an online survey. The result revealed that household crowdedness was predictive of parents’ COVID-related. Furthermore, parents’ COVID-related stress significantly mediated the associations between household crowdedness and children's internalizing and externalizing behaviors, controlling for family socioeconomic status. The study contributed to the growing research on the impact of the physical living environment as part of the ecological systems on family and child functioning. In time of crisis, young children rely on schools to support their development and wellbeing. The current findings caution the decision of school closure.