[Efficacy of photocatalytic removal of Chromium in the presence of organic matter from aqueous medium by useing TiO2 nanoparticles synthesized by sol gel]

Background and Aim: Widespread use of Chromium and their compounds in many industries, including plating, steel production, and wood protection and tanning leather, can result in the discharge of large amounts of pollutants to receiving waters, leading to toxic effects on human health and the environment. The aim of this study was to determine the efficiency of the photocatalytic process to remove Chromium in the presence of organic matter from the aqueous medium by using nanoparticles of TiO2 synthesized by sol gel

Materials and Methods: This was an experimental study. After nanoparticle synthesis, we used FTIR, SEM, XRD for analysis of nanoparticles. The photocatalytic process for Chromium removal was performed using a discrete stream reactor and Uv light bulb with 30 watts intensity. Then, the effects of independent variables, including pH, concentration of nanoparticles, contact time and the presence of interfering organic matters such as phenol, EDTA, CCl4, methanol and humic acid on the efficiency of the removal of Chromium in an aqueous medium were evaluated

Results: The results showed efficiency of Chromium removal increased after decreasing pH. Also, increasing the concentration of nanoparticles and contact time led to increased removal efficiency. We found reduced removal efficiency after increasing concentrations of the pollutants. Removal efficiency of Chromium increased in the presence of EDTA, but methanol, phenol, humic acid, and carbon tetrachloride reduced its removal efficiency

Conclusion: Photocatalytic oxidation with titanium oxide nanoparticles synthesized by sol- gel method can be an effective way for removal of Chromium from aqueous medium

[Ex vivo evaluation of the accuracy of the raypex 5 electronic apex locator to detect root perforation]

Introduction: Root perforation diagnosis and immediate treatment of the lesion, can improve the prognosis of the treatment. Because of the limitations of radiographic method for determining proper location of the perforation, today using electronic apex locator devices was recommended for root perforation detection

Objective: Evaluate the accuracy of the Raypex 5 apex locator for detecting root perforation and compare it with radiographic method

Materials and Methods: Twenty extracted anterior central teeth with apical foramen diameter equal to file 30 or 35 were selected. The roots were perforated using a 1/2 round bur at 1/3 middel of the root. Then, actual electronic and radiographic distance to perforation were measured. Data were analyzed using ANOVA with repeated measurements

Results: Raypex 5 apex locator could detect root perforations in 55% of the cases. In these cases, no significant difference was observed between the mean electronic and actual length of the perfortion[p=0.29]. There was no significant difference between the mean radiographic and actual length of the perfortion [p=0.444]. There was no significant difference between the mean radiographic and electronic length. [p=0.819]

Conclusion: Raypex 5 could detect root perforation in only 55% of the cases. In these cases, electronic length had no significant difference with actual and radiographic length

[Mental health and psychological consequences of chronic low back pain in a group of Iranian labors]

The present study examines the mental health of labors diagnosed with CLBP in one of the Iranian industrial factory as one of the top ranked factories in the Middle-East. In all, 45 people with CLBP and 72 controls were entered into the study. The General Health Questionnaire [GHQ-28] and a pain questionnaire were administered to assess mental health and pain intensity. Findings showed a significant difference between the two groups; the overall level of mental health in CLBPP was significantly lower than the control group. However, no significant difference was shown in the Social Dysfunctional [SD] subscale, CLBP patients showed a noticeable difference in the rest subscales. Patients with more sick leave, showed more anxiety, depression and social dysfunction. In addition, there were significant difference in the sleep disorder, fatigue and job satisfaction between CLBP patients and control group but no significant difference was shown in the smoking. According to our hypothesis, CLP impressed mental health in more aspects; anxiety and depression as two important factors for disability are related to sick leave and job satisfaction. Main results of the present study are congruent with the previous researches in this field

[Evaluation of epidemiologic characteristics of patients with gastric cancers in Shohada-e-Tajrish Medical Center between the 1378-1384]

Background: gastric cancers are amongst the most common malignancies of upper intestine. Due to its particular anatomy in terms of widespread and complex lymphatic network, it rapidly invades and spreads into far distance which will be refractive to treatment

Methods and materials: this was a case series survey. All files of patients with documented gastric cancer between 1378 and 1384 were reviewed. The data were analyzed with SPSS- 11/5

Results: the mean age was 63/5 +/- 1. Adenocarcinoma with the prevalence of 96/8% was the most common malignancy. Epigastric pain [67%] and weight loss [66%] were the most common symptoms. Antrium [43%] was the most common site of involvement. Dysphagia and weight loss had statistically significant correlation with survival [P<0.05]. With regard to the site of involvement, proximal tumors had statistically significant relation with survival [P<0.05]

Conclusion: the obtained results represent that patients with epigastric pain and anorexia had the worst prognosis. The prognosis of proximal tumors was the worst. Among different surgical procedures, subtotal gostrectromy had the best prognosis

[ effect of three temporary restorative material thickness coronal micro leakage in endodontics- an in - vitro study]

Introduction: Maintaining an adequate coronal access seal is an integral part of multiple-visit endodontic therapy or after root canal treatment until crown reconstruction. This is provided by filling the access cavity with temporary restorative materials. The thickness of the temporary restorative materials is one of the important factors in preventing of coronal microleakage

Objective: This research was conducted to determine the effect of the thickness of three temporary restorative materials of Cavizol, Cavtemp and Coltosol on coronal micro leakage of extracted human teeth

Materials and Methods: In this Invitro study, 100 multi rooted posterior human teeth, were randomly divided into nine experimental groups [n=10] and two negative and positive control group [n=5]. According to manufacture's instruction, the access cavities in experimental groups were filled with three temporary materials, Cavizol, Cavtemp, Coltozol in 2, 3, 4 mm thickness each. Linear dye penetration and clearing technique were used to evaluate coronal leakage of temporary filling materials. Data was analyzed with one way ANOVA test

Results: Comparison of experimental groups in different thicknesses [2, 3, 4 mm] showed no statistical difference [p<0.05] of coronal leakage between different groups as regard as to level

Conclusion: There was no preference between the materials were put for preventing coronal micro leakage. There was no limitation for their essential thickness in access cavity. So they may be suited for clinical situations in access cavities which have the depth of 2 mm or more