A case control study of acute leukemia risk factors in adults, Shiraz, Iran.

Abstract: Background: Leukemia is one of the most common cancers in Iran. Few studies have focused on identifying the causative factors for leukemia. This implies the necessity of this case-control study. This study was undertaken to identify possible risk factors associated with leukemia. Materials and Methods: In a case-control study matched by age and sex. 100 leukemic patients admitted in hematology wards in Namazee Hospital affiliated to Shiraz University of Medical Sciences were enrolled. Control group compromised 100 ..

Improvement of a nano-scale silicon on insulator field effect transistor performance using electrode, doping and buried oxide engineering

In this work, a novel Silicon on Insulator (SOI) MOSFET is proposed and investigated. The drain and source electrode structures are optimized to enhance ON-current while global device temperature and hot carrier injection are decreased. In addition, to create an effective heat passage from channel to outside of the device, a silicon region has embedded in the buried oxide. In order to reduce the device leakage current and controlling the threshold voltage, a p-type retrograde doping is introduced into channel region. Since the air has the least permittivity among materials, it can be utilized to decrease the device parasitic capacitances. Based on this, an air gap is embedded in the buried oxide near the silicon to improve RF performance of the device. Because the source and drain electrodes are embedded in and over the silicon film in the source and drain regions, we called this structure EEIOS-SOI MOSFET. “EEIOS” stands for “Embedded Electrodes In and Over the Silicon film”. During this work, EEIOS-SOI MOSFET is compared with a conventional SOI MOSFET and another SOI MOSFET with just Embedded Electrodes In the Silicon Film (EEIS-SOI). EEIS-SOI presents better electrical figure of merits including lower subthreshold slope and lower leakage current in simulations. An immense investigation among these devices shows that EEIOS-SOI MOSFET has better transconductance, lower gate injection leakage current and lower temperature related to DC parameters and higher cut off frequency, gain bandwidth product and unilateral power gain related to AC figures of merits compared to its counterparts

Improvement of a nano-scale silicon on insulator field effect transistor performance using electrode, doping and buried oxide engineering

In this work, a novel Silicon on Insulator (SOI) MOSFET is proposed and investigated. The drain and source electrode structures are optimized to enhance ON-current while global device temperature and hot carrier injection are decreased. In addition, to create an effective heat passage from channel to outside of the device, a silicon region has embedded in the buried oxide. In order to reduce the device leakage current and controlling the threshold voltage, a p-type retrograde doping is introduced into channel region. Since the air has the least permittivity among materials, it can be utilized to decrease the device parasitic capacitances. Based on this, an air gap is embedded in the buried oxide near the silicon to improve RF performance of the device. Because the source and drain electrodes are embedded in and over the silicon film in the source and drain regions, we called this structure EEIOS-SOI MOSFET. “EEIOS” stands for “Embedded Electrodes In and Over the Silicon film”. During this work, EEIOS-SOI MOSFET is compared with a conventional SOI MOSFET and another SOI MOSFET with just Embedded Electrodes In the Silicon Film (EEIS-SOI). EEIS-SOI presents better electrical figure of merits including lower subthreshold slope and lower leakage current in simulations. An immense investigation among these devices shows that EEIOS-SOI MOSFET has better transconductance, lower gate injection leakage current and lower temperature related to DC parameters and higher cut off frequency, gain bandwidth product and unilateral power gain related to AC figures of merits compared to its counterparts

Ranking World Cup 2014 Football Matches by Data Envelopment Analysis Models with Common Weights

Football is one of the most popular and exciting sports fields throughout the world. Today, in addition to the result, the number of goals and points, attraction and quality of the played matches are important for club management staff, coaching staff, the players and especially the fans. Beside number of goals, there are different criteria such as successful passes, attacks, defenses, tackles and etc. can determine the quality of matches. Therefore, in this survey, researchers consider the quality of World Cup 2014 football matches. For this purpose, after the review on research literature, the quality criteria of football matches are determined. Afterward, related data of each criterion are extracted. Then, the DEA common weight analysis (DEA-CWA) is used in order to evaluate and rank the quality of competitions. Results show that the match between the national teams of Argentina and Nigeria was elected as the highest-quality match in Brazil's 2014 World Cup first round

Effect of Calcium Hydroxide on the Push-out Bond Strength of Endodontic Biomaterials in Simulated Furcation Perforations

Introduction: The aim of this in vitro study was to evaluate the effect of calcium hydroxide (CH) on push-out bond strength of white mineral trioxide aggregate (WMTA) and calcium-enriched mixture (CEM) cement in simulated furcation perforations. Methods and Materials: Furcation perforations, measuring 1.3 mm in diameter and 2 mm in height, were created in 80 human mandibular first molars. The teeth were then divided into 4 groups (n=20). In groups 1 and 3 CH was placed in the perforation for one week, before placement of WMTA and CEM. In groups 2 and 4 perforations were repaired without placement of CH. In groups 1 and 2 the perforation sites were repaired with WMTA and CEM cement was used in groups 3 and 4. After 7 days, the push-out test was carried out using a universal testing machine. Data were analyzed with two-way ANOVA. The level of significance was set at 0.05. Results: The maximum and minimum bond strength values were recorded in the WMTA/CH (13.08±1.8 MPa) and CEM cement groups (8.03±0.98 MPa), respectively. There were significant differences in resistance to dislodgement between the WMTA/CH and other groups (P<0.05). Conclusion: Placement of CH before placement of WMTA in furcation perforation improves the push-out bond strength of this material.Keywords: Calcium-Enriched Mixture; Calcium Hydroxide; Furcation Perforation; Mineral Trioxide Aggregate; Push-Ou

Accuracy of Cone-Beam Computed Tomography in Determining the Root Canal Morphology of Mandibular First Molars

Introduction: The aim of the present in vitro study was to compare the accuracy of cone-beam computed tomography (CBCT) in determining root canal morphology of mandibular first molars in comparison with staining and clearing technique. Methods and Materials: CBCT images were taken from 96 extracted human mandibular first molars and the teeth were then evaluated based on Vertucci’s classification to determine the root canal morphology. Afterwards, access cavities were prepared and India ink was injected into the canals with an insulin syringe. The teeth were demineralized with 5% nitric acid. Finally, the cleared teeth were evaluated under a magnifying glass at 5× magnification to determine the root canal morphology. Data were analyzed using the SPSS software. The Fisher’s exact test assessed the differences between the mesial and distal canals and the Cohen’s kappa test was used to assess the level of agreement between the methods. Statistical significance was defined at 0.05. Results: The Kappa coefficient for agreement between the two methods evaluating canal types was 0.346 (95% CI: 0.247-0.445), which is considered a fair level of agreement based on classification of Koch and Landis. The agreement between CBCT and Vertucci’s classification was 52.6% (95% CI: 45.54-59.66%), with a significantly higher agreement rate in the mesial canals (28.1%) compared to the distal canals (77.1%) (P<0.001). Conclusion: Under the limitations of this study, clearing technique was more accurate than CBCT in providing accurate picture of the root canal anatomy of mandibular first molars.Keywords: Cone-Beam Computed Tomography; Root Canal Morphology; Root Clearin