65 research outputs found

    Sens-BERT: Enabling Transferability and Re-calibration of Calibration Models for Low-cost Sensors under Reference Measurements Scarcity

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    Low-cost sensors measurements are noisy, which limits large-scale adaptability in airquality monitoirng. Calibration is generally used to get good estimates of air quality measurements out from LCS. In order to do this, LCS sensors are typically co-located with reference stations for some duration. A calibration model is then developed to transfer the LCS sensor measurements to the reference station measurements. Existing works implement the calibration of LCS as an optimization problem in which a model is trained with the data obtained from real-time deployments; later, the trained model is employed to estimate the air quality measurements of that location. However, this approach is sensor-specific and location-specific and needs frequent re-calibration. The re-calibration also needs massive data like initial calibration, which is a cumbersome process in practical scenarios. To overcome these limitations, in this work, we propose Sens-BERT, a BERT-inspired learning approach to calibrate LCS, and it achieves the calibration in two phases: self-supervised pre-training and supervised fine-tuning. In the pre-training phase, we train Sens-BERT with only LCS data (without reference station observations) to learn the data distributional features and produce corresponding embeddings. We then use the Sens-BERT embeddings to learn a calibration model in the fine-tuning phase. Our proposed approach has many advantages over the previous works. Since the Sens-BERT learns the behaviour of the LCS, it can be transferable to any sensor of the same sensing principle without explicitly training on that sensor. It requires only LCS measurements in pre-training to learn the characters of LCS, thus enabling calibration even with a tiny amount of paired data in fine-tuning. We have exhaustively tested our approach with the Community Air Sensor Network (CAIRSENSE) data set, an open repository for LCS.Comment: 1

    The Association between Educational Achievements, Career Aspirations, Achievement Motives and Oral Hygiene Behavior among Dental Students of Udaipur, India

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    Background: There are several factors which influence oral hygiene behavior of an individual. Educational achievements, career aspirations and achievement motives of individuals are some of those factors. The objective of this study was to investigate whether educational achievements, career aspirations and achievement motives have associations with oral hygiene behavior among dental students of Udaipur, India.Methods: A descriptive cross-sectional study was conducted among all (n=200) 1st year dental students from all dental colleges of Udaipur City, India. Self-administered structured questions were used to assess their educational achievements, career aspirations and oral hygiene behavior (OHB). Achievement motives were assessed using Achievement Motive Scale developed by Lang and Fries (2006). Chi-square test and multivariate logistic regression tests were used in data analysis. Confidence level and level of significance were set at 95% and 5% respectively.Results: Students with better educational achievements undergone regular dental check-up (30.48%) (p=0.03) and used other oral hygiene aids (90.24%) (p=0.01). Tooth brushing frequency, time and replacement time of tooth brush were found to be significantly associated with career aspiration (p=0.007; p=0.002; p=0.00 respectively). Achievement motives did not have statistically significant association with oral hygiene behavior.Conclusion: Educational achievements and career aspirations appear to be associated with oral hygiene behavior of young dental students. Students with higher career aspirations practiced better oral hygiene behavior. There was no significant relationship between achievement motives and oral hygiene behavior.Keywords: Educational achievements, career aspirations, achievement motives, oral hygiene

    Low incidence of positive smooth muscle antibody and high incidence of isolated IgM elevation in Chinese patients with autoimmune hepatitis and primary biliary cirrhosis overlap syndrome: a retrospective study

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    <p/> <p>Background</p> <p>Up to now, few data are available regarding the clinical characteristics of autoimmune hepatitis and primary biliary cirrhosis overlap syndrome. The study was to investigate and analyze the prevalent and clinical features of Chinese patients with this disease.</p> <p>Methods</p> <p>Clinical data on patients diagnosed as autoimmune hepatitis and primary biliary cirrhosis overlap syndrome in our hospital from January 2001 to December 2006 were collected and analyzed.</p> <p>Results</p> <p>Overlap syndrome of autoimmune hepatitis and primary biliary cirrhosis accounted for 10.33% of patients with autoimmune liver diseases during the past six years. For these patients with overlap syndrome, xanthochromia, lethargy and anorexia were the predominant complaints; a low incidence (14/146) of smooth muscle antibody positivity and a high incidence (37/89) of isolated IgM elevation were the main serological characteristics.</p> <p>Conclusions</p> <p>Overlap syndrome of autoimmune hepatitis and primary biliary cirrhosis was not rare in Chinese patients with clinical manifests of autoimmune liver diseases. Overlap of the diseases should not be disregarded when isolated IgM elevation was exhibited, and smooth muscle antibody might have little diagnostic significance in the overlap syndrome. If it was difficult to make a definite diagnosis, liver biopsy was necessary.</p
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