Background Early childhood caries is the most common infectious disease in childhood, with a high prevalence in developing countries. The assessment of the variables that influence early childhood caries as well as its pathophysiology leads to improved control of this disease. Cystatin S, as one of the salivary proteins, has an essential role in pellicle formation, tooth re-mineralization, and protection. The present study aims to assess salivary cystatin S levels and demographic data in early childhood caries in comparison with caries-free ones using statistical analysis and machine learning methods. Methods A cross-sectional, case–control study was undertaken on 20 cases of early childhood caries and 20 caries-free children as a control. Unstimulated whole saliva samples were collected by suction. Cystatin S concentrations in samples were determined using human cystatin S ELISA kit. The checklist was collected from participants about demographic characteristics, oral health status, and dietary habits by interviewing parents. Regression and receiver operating characteristic (ROC) curve analysis were done to evaluate the potential role of cystatin S salivary level and demographic using statistical analysis and machine learning. Results The mean value of salivary cystatin S concentration in the early childhood caries group was 191.55 ± 81.90 (ng/ml) and in the caries-free group was 370.06 ± 128.87 (ng/ml). T-test analysis showed a statistically significant difference between early childhood caries and caries-free groups in salivary cystatin S levels (p = 0.032). Investigation of the area under the curve (AUC) and accuracy of the ROC curve revealed that the logistic regression model based on salivary cystatin S levels and birth weight had the most and acceptable potential for discriminating of early childhood caries from caries-free controls. Furthermore, using salivary cystatin S levels enhanced the capability of machine learning methods to differentiate early childhood caries from caries-free controls. Conclusion Salivary cystatin S levels in caries-free children were higher than the children with early childhood caries. Results of the present study suggest that considering clinical examination, demographic and socioeconomic factors, along with the salivary cystatin S levels, could be usefull for early diagnosis ofearly childhood caries in high-risk children; furthermore, cystatin S is a protective factor against dental caries.

A study of the global flow of US-based svod s, and their absence or presence within domestic media ecosystems, allows us to move beyond universalist approaches in platform studies. Starting with an analysis of the politics of Netflix’s absence from Iran’s media landscape, this article studies the contribution of domestic svod s to the diversification of the Iranian movie culture. It argues that filtering Netflix in Iran is part of a long history of content regulation and the state’s plan to support local platforms. The dynamic informal circulation networks in Iran also pose challenges for foreign svod s. Focusing on domestic platforms like Filimo, the article argues that they became part of a national project to battle piracy domestically. Iran’s laws as a non-signatory of international treaties on intellectual property, however, allow them to acquire foreign films through informal markets, situating these platforms in an ambiguous state in between formal and informal services.

Background: Early childhood caries is the most common infectious disease in childhood, with a high prevalence in developing countries. Recognition of the factors affecting early childhood caries and its pathophysiology, allows better control of disease. Cystatin S as one of the salivary proteins, has an important role in pellicle formation, tooth re-mineralization and protection. The aim of the present study is to assess salivary cystatin S levels and demographic data in early childhood caries children in comparison with caries-free ones using statistical analysis and machine learning methods. Methods: A cross-sectional case-control study was undertaken on 20 cases of early childhood caries and 20 caries-free children as a control group. Unstimulated whole saliva samples by suction method was collected. Cystatin S concentrations were determined using human cystatin S ELISA kit. A checklist was collected for each participant about the demographic characteristics, oral health status and dietary habits by interviewing parents. The regression and receiver operating characteristic (ROC) curve analysis was done to evaluate the potential role of cystatin S salivary level and demographic using machine learning and statistical analysis.Results: The mean value of salivary cystatin S concentration in early childhood caries group was 191.55±81.90 (ng/ml) and in caries-free group was 370.06±128.87 (ng/ml). T-test analysis showed that there is a statistically significant difference between early childhood caries and caries-free group in salivary cystatin S level (p: 0.032). Investigation of area under the curve and accuracy of ROC curve revealed that logistic regression model based on the salivary cystatin S levels and birth weight had most and acceptable potential for discriminating of early childhood caries from caries-free controls. After that the machine learning models and finally salivary cystatin S levels had more capability for differentiation of early childhood caries from caries-free controls.Conclusion: Salivary cystatin S in caries-free children was higher than the children with early childhood caries. Therefore, cystatin S protein can be used as a biomarker for early prediction of early childhood caries, furthermore cystatin S is a protective factor against dental caries.