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BACKGROUND AND OBJECTIVE: There is a risk of damage to the inferior alveolar nerve when extracting third molars. A variety of common imaging modalities, such as panoramic radiography (PR) and cone-beam computed tomography (CBCT), are recommended for examination prior to mandibular third molar surgery. The aim of this study was to compare the findings of panoramic radiography and CBCT in evaluating the relation between the root of the mandibular third molar and the inferior alveolar canal. METHODS: In this cross-sectional study, 75 panoramic and CBCT images were evaluated. Cases in panoramic radiography that were suspected of the relation between the root of the mandibular third molars and the inferior alveolar canal were collected. To determine the type of connection of apex and root canal, the samples were divided into 6 groups: normal, inferior alveolar canal path loss, canal path narrowing, sudden canal path change, radiolucent band over the roots, and root curvature. Cases in the panoramic radiograph that were suspected of root contact with the canal were examined by the CBCT in terms of the position of the canal relative to the tooth (buccal or lingual or middle of the root - upper or lower) and the type of connection (whether the tooth is connected to the canal). FINDINGS: In panoramic findings, 23 cases (30.7%) were normal, 19 cases (25.3%) showed canal path loss, 9 cases (12%) canal path narrowing, 5 cases (6.7%) sudden canal path change, 3 cases (4%) radiolucent band over the roots and 16 cases (21.3%) showed root curvature. According to CBCT findings, the position of the canal relative to the root apex was lingual in 39 cases (52%) and there was connection between the mandibular canal and the third molar in 39 cases (78.7%). There was no significant relationship between panoramic radiographic and CBCT findings and only in two cases of specific radiolucent band over the roots, there was a complete agreement between panoramic and CBCT findings. CONCLUSION: Based on the results of this study, if a radiolucent band is observed on the root of the mandibular molars or a sudden change is observed in the canal path, panoramic radiography can be used to detect the relation between the inferior alveolar canal and the root of the third molars. [ABSTRACT FROM AUTHOR]

The objective of this paper is to apply time series analysis and multiple regression method to ozone data in order to obtain the optimal statistical model for forecasting next day ozone level. The best estimated model is then used to produce one-step ahead point and interval estimates of future values of the ozone series. Ozone data is analyzed using time series analysis, which resulted in an Auto Regressive Moving Average, ARMA (20, 2) with Mean Absolute Percentage Error (MAPE)=42%. Applying multiple regression method and examination of several possible contributing factors, showed that Wind speed, Mixing height where the complex chemical reactions that produce ozone take place, current and predicted next day temperatures and current ozone concentration are influential on the next day ozone concentration levels. Diagnostics tests and statistics including R-square, residual analysis and Durbin-Watson Statistic (DW) were applied in order to select the best fitted model and finally the best prediction model was found using MAPE and Mean Absolute Deviation (MAD) as predictive criteria. Regression analysis of this data, using tomorrow's and today's maximum temperature, today's wind speed and tomorrow's maximum height at 10 am, as explanatory variables results in R-square of 50.7% with MAD=12.423, MAPE=30% and DW=1.66 [ABSTRACT FROM AUTHOR]

WASP-12 b, WASP-33 b, WASP-36 b, and WASP-46 b are four transiting hot Jupiters, which we have studied. These systems' light curves were derived from observations made by the Transiting Light Exoplanet Survey Satellite (TESS) and some ground-based telescopes. We used Exofast-v1 to model these light curves and calculate mid-transit times. Also, we plotted TTV diagrams for them using derived mid-transit times and those available within the literature. O–C analysis of these timings enables us to refine the linear ephemeris of four systems. We measured WASP-12's tidal quality factor based on adding TESS data as . According to the analysis, the orbital period of the WASP-46 b system is increasing. The WASP-36 b and WASP-33 b systems have not shown any obvious quadratic trend in their TTV diagrams. The increase in their period is most likely due to inaccurate liner ephemeris that has increased over time. So, more observations are needed to evaluate whether or not there is an orbital decay in the WASP-36 b and WASP-33 b systems. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: Matrix metalloproteinases (MMPs) are a group of enzymes responsible for extracellular matrix breakdown. Increased activity of type 13 is involved in invasion of oral squamous cell carcinoma. This study was performed to compare the level of matrix metalloproteinase13 (MMP13) in saliva and serum of patients with oral squamous cell carcinoma and healthy controls. METHODS: In this experimental in vitro study, 24 saliva and 24 serum samples were collected from patients with primary oral squamous cell carcinoma after histopathologic confirmation, whereas 21 saliva samples and 21 serum samples were collected from healthy subjects with mucosal health confirmation. Clinical examination was done for MMP-13 levels in saliva and serum, and the results were compared by ELISA. FINDINGS: MMP-13 levels in serum (7.47±2.36) and saliva (8.42±2.69) of patients with oral squamous cell carcinoma compared to healthy subjects increased respectively by 5.39±1.90 and 6.72±2.11 (P= 0.002 and P= 0.025, respectively). The levels of MMP13 in saliva and serum to determine the existence of oral squamous cell carcinoma has a "good" diagnostic value, with sensitivity and specificity of 88% and 86% respectively for serum, and 88% and 71% respectively for saliva. CONCLUSION: According to the results of this study, the levels of MMP13 in saliva and serum of patients with oral squamous cell carcinoma was higher than in healthy individuals and this biomarker had good diagnostic value in the diagnosis of oral squamous cell carcinoma. [ABSTRACT FROM AUTHOR]