A Novel Approach to Chest X-ray Lung Segmentation Using U-net and Modified Convolutional Block Attention Module

Lung segmentation in chest X-ray images is of paramount importance as it plays a crucial role in the diagnosis and treatment of various lung diseases. This paper presents a novel approach for lung segmentation in chest X-ray images by integrating U-net with attention mechanisms. The proposed method enhances the U-net architecture by incorporating a Convolutional Block Attention Module (CBAM), which unifies three distinct attention mechanisms: channel attention, spatial attention, and pixel attention. The channel attention mechanism enables the model to concentrate on the most informative features across various channels. The spatial attention mechanism enhances the model's precision in localization by focusing on significant spatial locations. Lastly, the pixel attention mechanism empowers the model to focus on individual pixels, further refining the model's focus and thereby improving the accuracy of segmentation. The adoption of the proposed CBAM in conjunction with the U-net architecture marks a significant advancement in the field of medical imaging, with potential implications for improving diagnostic precision and patient outcomes. The efficacy of this method is validated against contemporary state-of-the-art techniques, showcasing its superiority in segmentation performance

Canal Transportation and Centering after Using PathFile and R-Pilot in Mesiobuccal Canals of Maxillary Molars Using Cone-Beam Computed Tomography

Introduction: This study aimed to compare the changes in root canal anatomy following the use of PathFile and R-Pilot using cone-beam computed tomography (CBCT). Methods and Materials: In this in vitro, experimental study, 60 extracted maxillary first and second molars with 20 to 40° mesiobuccal root curvature, minimum of 19 mm of root length, no calcified root canals and no history of previous treatment were divided into two groups (n=30). CBCT scans were taken before and after the treatment, and sections at 1, 2 and 3 mm from the apex were compared. Pairwise comparisons were carried out using the Mann Whitney-U test. The centering ratio data were analyzed using the Chi-square test and Fisher’s exact test. All statistical analyses were carried out using Sigma Stat 4 software. Results: The difference between PathFile and R-Pilot in canal transportation in mesiodistal direction was significant at 1 and 2 mm from the apex (P<0.01). The R-Pilot file was significantly superior to PathFile in centering ability in mesiodistal direction at 1 mm from the apex (P<0.05). Canal transportation direction was towards the mesiolingual and distobuccal in R-Pilot and PathFile groups, respectively. Conclusion: Within the limitations of this study, the results showed that R-Pilot with reciprocal movement is a safe and easy to use instrument for creating a glide path.Keywords: Canal Transportation; Cone-Beam Computed Tomography; Glide Path; PathFile; R-Pilo

Negotiation, Centering Ability and Transportation of Three Glide Path Files in Second Mesiobuccal Canals of Maxillary Molars: A CBCT Assessment

Introduction: The aim of this study was to compare negotiation, centering ability and transportation of three path finder rotary instruments (ProGlider, ScoutRace and M3 Pro-Gold Path File) to create glide path in second mesiobuccal (MB2) canals of maxillary molars with cone-beam computed tomography (CBCT). Methods and Materials:  In this in vitro study, 66 maxillary molars with separate second MB2 canals were selected with the following criteria: having 18-21 mm root length, without any resorption or calcification in radiography, without previous treatment and 20-40ºcurve according to Schneider’s method. Then MB2 canals were randomly divided into three groups (n=22). CBCT scan before and after root canal negotiation was taken. A #10 K-file for determination of working length was inserted into all canals. In group1; ProGlider file, group2; ScoutRace file and in group 3; M3 Pro-Gold Path file was implemented. The calculated data from CBCT based on reaching full working length (RFWL) or not (NRFWL) were analyzed using the Pearson Chi-square test. Centering ability was calculated by Fisher’s exact test and amount of transportation was determined with the Pearson Chi-square test in SPSS software. Results: ProGlider file had the least RFWL and ScoutRace was the best, but the results were not statistically significant (P>0.05). Regarding the centering ability and transportation, all 3 groups showed no significant differences (P>0.05), except at level of 2 mm from the apex in buccopalatal direction for ProGlider and ScoutRace files (P<0.05). Conclusion: In spite of insignificantly different results, ScoutRace file was better than other groups in negotiating and centering ability in mesiodistal direction of the MB2 canal in maxillary molars. Also, ProGlider file was significantly better than ScoutRace regarding transportation at level of 2 mm from apex in buccopalatal direction.Keywords: Centering Ability; Cone-Beam Computed Tomography; ProGlider; Second Mesiobuccal Canal; Transportation

Biocompatibility of Portland Cement Modified with Titanium Oxide and Calcium Chloride in a Rat Model

Introduction: The aim of the present study was to evaluate the biocompatibility of two modified formulations of Portland cement (PC) mixed with either titanium oxide or both titanium oxide and calcium chloride. Methods and Materials: Polyethylene tubes were filled with modified PCs or Angelus MTA as the control; the tubes were then implanted in 28 Wistar rats subcutaneously. One tube was left empty as a negative control in each rat. Histologic samples were taken after 7, 15, 30 and 60 days. Sections were assessed histologically for inflammatory responses and presence of fibrous capsule and granulation tissue formation. Data were analyzed using the Fisher’s exact and Kruskal-Wallis tests. Result: PC mixed with titanium oxide showed the highest mean scores of inflammation compared with others. There was no statistically significant difference in the mean inflammatory grades between all groups in each of the understudy time intervals. Conclusion: The results showed favorable biocompatibility of these modified PC mixed with calcium chloride and titanium oxide.Keywords: Biocompatibility; Mineral Trioxide Aggregate; Portland Cemen

Why Do Emergency Medicine Residents Experience Burn Out? A qualitative study

Objective: Emergency medicine residents are a high–risk group for burnout syndrome. This was a qualitative study with content analysis on emergency medical residents with 2 aims: evaluating the incidence of occupational burnout syndrome and identifying the points of view and attitudes of emergency medical residents about factors related to occupational burnout syndrome. Method: For this study, 2 sessions of focus group discussions were set up at Imam Khomeini hospital affiliated to Tehran University of Medical Sciences. Each session took 90 minutes, and 20 emergency medicine residents in their first or second year of emergency medicine residency participated in the sessions. Data were coded   by MAXQDA10 software. Results: Data were categorized in 4 themes as follow: (1) the characteristics of emergency medicine; (2) ambiguity in residents’ duties; (3) educational planning; and (4) careers. Data on the proposed solutions by residents were analyzed and coded in 3 groups including (1) changes in personal life; (2) arrangement in shifts; and  (3) educational issues. Conclusion: According to findings of this qualitative study, most of emergency medicine residents have experienced exhaustion sometime during the course of their residency. Psychological supports may help the residents to cope with their career difficulties and probable burn out

Enhancing Price Prediction in Cryptocurrency Using Transformer Neural Network and Technical Indicators

This study presents an innovative approach for predicting cryptocurrency time series, specifically focusing on Bitcoin, Ethereum, and Litecoin. The methodology integrates the use of technical indicators, a Performer neural network, and BiLSTM (Bidirectional Long Short-Term Memory) to capture temporal dynamics and extract significant features from raw cryptocurrency data. The application of technical indicators, such facilitates the extraction of intricate patterns, momentum, volatility, and trends. The Performer neural network, employing Fast Attention Via positive Orthogonal Random features (FAVOR+), has demonstrated superior computational efficiency and scalability compared to the traditional Multi-head attention mechanism in Transformer models. Additionally, the integration of BiLSTM in the feedforward network enhances the model's capacity to capture temporal dynamics in the data, processing it in both forward and backward directions. This is particularly advantageous for time series data where past and future data points can influence the current state. The proposed method has been applied to the hourly and daily timeframes of the major cryptocurrencies and its performance has been benchmarked against other methods documented in the literature. The results underscore the potential of the proposed method to outperform existing models, marking a significant progression in the field of cryptocurrency price prediction

Traditional Timing of Qanat Water Shares

Paper presented at the International Conference on Traditional Knowledge for Water Resources Management, Yazd, Iran, 21–23 February 2012.Until recently, it was thought by the authors that only the water clock together with regulation by means of small reservoirs were used for timing water shares for the qanats of Iran. However, this was not the case. This paper presents recent findings about traditional timing of water, mainly in the Central Plateau of Iran, with a focus on star use. Comparisons are made with Oman, where stars and sundials are still used in places for this purpose.Up to the 1950s, water clocks were widely used for timing qanat water shares both by day and by night. However, in a few places, sundials were used by day and stars by night, at least at certain times of year. It appears that stars were widely used to know the time at night, while for water division they were used only on certain qanats, and mainly in winter, when short water shares were not needed. Keeping the time was often the responsibility of only one or two people, and the few surviving people with any knowledge of this practice are now old. This oral history is, therefore, in imminent danger of disappearing completely