38 research outputs found
Slaughterhouse Wastewater Treatment by Combined Chemical Coagulation and Electrocoagulation Process
Slaughterhouse wastewater contains various and high amounts of organic matter (e.g., proteins, blood, fat and lard). In order to produce an effluent suitable for stream discharge, chemical coagulation and electrocoagulation techniques have been particularly explored at the laboratory pilot scale for organic compounds removal from slaughterhouse effluent. The purpose of this work was to investigate the feasibility of treating cattle-slaughterhouse wastewater by combined chemical coagulation and electrocoagulation process to achieve the required standards. The influence of the operating variables such as coagulant dose, electrical potential and reaction time on the removal efficiencies of major pollutants was determined. The rate of removal of pollutants linearly increased with increasing doses of PACl and applied voltage. COD and BOD5 removal of more than 99% was obtained by adding 100 mg/L PACl and applied voltage 40 V. The experiments demonstrated the effectiveness of chemical and electrochemical techniques for the treatment of slaughterhouse wastewaters. Consequently, combined processes are inferred to be superior to electrocoagulation alone for the removal of both organic and inorganic compounds from cattle-slaughterhouse wastewater
Investigating the sequential patterns of methamphetamine use initiation in Iran
BACKGROUND: Methamphetamine (MA) remains one of the most commonly used amphetamine-type stimulants, accounting for the second most widely-used substance after marijuana. Due to increased use of MA, a wide variety of research has focused on the patterns of MA use initiation among adolescents. Nevertheless, there are few data available for people who use MA. The present study set out to assess the sequential patterns of substance use initiation in patients with MA use disorders in Iran. MATERIALS AND METHODS: This cross-sectional study described substance initiation patterns for 302 patients who used MA admitted to hospitals and psychiatric centers of Shiraz University of Medical Sciences. The study was conducted between April 2015 and June 2016. After obtaining informed consents, participants were interviewed by trained interviewers using face-to-face, semi-structured interviews. The collecting data were analyzed using the chi square tests and one-way analysis of variance (ANOVA) tests to compare the relationship between qualitative and quantitative variables, respectively. RESULTS: Out of 302 participants enrolled in the study, 16 (5.3%) and 286 (94.7%) were female and male, respectively. The mean age of participants in the study was 37.29 years. The mean age of onset of MA use was found to be 15.9 years. 46.1% of the patients started MA use before 15 years. 77.2% of the patients who used MA had family members with a history of substance use. 93.71% of the patients who used MA started substance use with tobacco, alcohol, or opium, as the most frequent substances. Tobacco, as the first substance or starting substance, exhibited the most widely-used substance (69.53% of the cases). Tobacco-alcohol-cannabis-opium-heroin-MA sequencing was significantly related to the early onset of the substance use. Early-onset substance use was significantly higher in those with lower income, primary education, and family history of substance use. No significant relationship was found between employment status with the age of onset of substance use, and different substance use with marital status. CONCLUSION: Tobacco, alcohol and opium can be considered as the main sequencing substances for initiation to MA use. Standardized measures to decrease and control access to main starting and sequencing substances, including tobacco, alcohol, and opium, can greatly help decrease the early onset of the MA use, develop suitable prevention, and establish early intervention strategies
A Novel Experience in Treatment of Liver Hydatidosis in Pediatrics: A Clinical Trial Study
Background Hydatidosis is a conventional health public problem in most parts of the world. Safe treatment of patients with hydatidosis has been a topic of debate for a long time. Surgical treatment always was associated with high morbidity and mortality. Medical treatment is also controversial. In this study, alternative procedure named Percutaneous, Aspiration and hypertonic Saline Instillation (PAHSI) was applied to treat patients with hydatidosis. Materials and Methods In this single-blind clinical trial, thirty-eight patients, ranging in age between 6 months and 16 years, with 81 hepatic hydatid cysts underwent PAHSI treatment. The consecutive steps including sonographic guidance, aspiration of cyst content and injection of 15% saline hypertonic were carried out in this method. Patients with multiple cysts also were treated by this procedure. Results Participants were 18 boys (47.3%) and 20 girls (52.6%) with mean age of 8.08+ 3.92 years. Almost half of the patients had single cyst (52.63%). During 2- year follow- up, no recurrences were observed; therefore, re-hospitalization and possible complications reduced considerably. Furthermore, this method was applicable to cure multiple cysts. Conclusion In PAHSI strategy, it seems that the complications of surgery (laparotomy and anesthesia) decreased since no complications observed after procedure, and cosmetic results in future are much better due to avoidance of incision
Optimal method for ablation of atypical AVNRT
Abstract Background Considering that ablation of atypical AVNRT may be unsuccessful after ablation at the right posterior septum, in this study, we aimed to present an optimal method for ablation of atypical AVNRT. Also, we evaluated the efficacy of this technique for preventing recurrences. Methods This is a prospective, double-center study. It was conducted on 62 patients with atypical AVNRT referred for radiofrequency ablation. The patients were randomly divided into two groups before ablation: 1-Group A (n = 30): treated with conventional ablation at the anatomic area of the slow pathway; 2-Group B (n = 32): ablation was done 2 mm higher in the septum during fluoroscopy. Results The mean age of patients in groups A and B were 54 ± 11.7 and 55 ± 12.2, respectively (P = 0.43). In group A, ablation was successful in 24 (80%) patients following right-sided slow pathway ablation, and the remaining patients required further treatment with either a left-side approach (N = 4, 13.3%) or ablation of additional regions (N = 2, 6.7%). In group B, ablation was successful in all patients. After a 48-month follow-up, recurrence of symptomatic atypical AVNRT was detected in 4 (13.3%) patients of group A and none of group B patients (p < 0.001). Conclusion In patients with atypical AVNRT, ablation 2 mm above the conventional area is more promising regarding success rate and recurrence of the arrhythmia
Humic Acid Removal from Aqueous Environments by Electrocoagulation Process Using Iron Electrodes
At present study the performance of electrocoagulation process using iron electrodes sacrificial anode has been investigated for removal of HA from artificial aqueous solution. The experiments were performed in a bipolar batch reactor with four iron electrode connected in parallel. Several working parameters, such as initial pH (3, 5, 7, and 9), electrical conductivity (50 V) and reaction time were studied in an attempt to achieve the highest removal capacity. Solutions of HA with concentration equal 20 mg L-1 were prepared. To follow the progress of the treatment, samples of 10 ml were taken at 15, 30, 45, 60, and 75 min interval. Finally HA concentration was measured by UV absorbance at 254 nm (UV254) and TOC concentration was measured by TOC Analyser. The maximum efficiency of HA removal which was obtained in voltage of 50 V, reaction time of 75 min, initial concentration 20 mg L-1, conductivity 3000 µS/Cm and pH 5, is equal to 92.69%. But for natural water samples at the same optimum condition removal efficiency was low (68.8 %). It can be concluded that the electrocoagulation process has the potential to be utilized for cost-effective removal of HA from aqueous environments
Textile Wastewater Treatment by Electrocoagulation Process using Aluminum Electrodes
Background and purpose: Textile industries are among the most polluting industries regarding the volume and the complexity of treatment of its effluents discharge. This study
investigated the efficiency of electrocoagulation process using aluminum electrodes in basic red 18 dye removal from aqueous solutions.
Materials and Methods: This study was performed in a bipolar batch reactor with six aluminum electrodes connected in parallel. Several important parameters, such as initial pH of solution, initial dye concentration, applied voltage; conductivity and reaction time were studied in an attempt to achieve higher removal efficiency.
Results: The electrochemical technique showed satisfactory dye removal efficiency and reliable performance in treating of basic red 18. The maximum efficiency of dye removal which was obtained in voltage of 50 V, reaction time of 60 min, initial concentration 50 mg/L, conductivity 3000 μS/cm and pH 7 was equal to 97.7%. Dye removal efficiency was increased accordance to increase of applied voltage and in contrast electrode and energy consumption was increased simultaneously.
Conclusion: As a conclusion, the method was found to be highly efficient and relatively fast compared to conventional existing techniques for dye removal from aqueous solutions
Habit Reversal Versus Object Manipulation Training for Treating Nail Biting: A Randomized Controlled Clinical Trial
Objective:This is a parallel, three group, randomized, controlled clinical trial, with outcomes evaluated up to three months after randomization for children and adolescents with chronic nail biting. The current study investigates the efficacy of habit reversal training (HRT) and compares its effect with object manipulation training (OMT) considering the limitations of the current literature .Method:Ninety one children and adolescents with nail biting were randomly allocated to one of the three groups. The three groups were HRT (n=30), OMT (n=30), and wait-list or control group (n=31). The mean length of nail was considered as the main outcome .Results:The mean length of the nails after one month in HRT and OMT groups increased compared to the waiting list group (P<0.001, P<0.001, respectively). In long term, both OMT and HRT increased the mean length of nails (P<0.01), but HRT was more effective than OMT (P<0.021). The parent-reported frequency of nail biting did show similar results as to the mean length of nails assessment in long term. The number of children who completely stopped nail biting in HRT and OMT groups during three months was 8 and 7, respectively. This number was zero during one month for the wait-list group .Conclusion:This trial showed that HRT is more effective than wait-list and OMT in increasing the mean length of nails of children and adolescents in long terms
Dormancy breaking and seed germination of the annual weeds Thlaspi arvense, Descurainia sophia and Malcolmia africana (Brassicaceae)
In Iran, Descurainia sophia, Malcolmia africana, and Thlaspi arvense are abundantly found as importunate weeds in winter cereal. Understanding the timing of seed germination under natural conditions is crucial for learning how to manage these annual weeds. Therefore, this study was conducted to evaluate the effect of soil burial, dry storage, cold stratification, KNO3, GA3, and scarification on the seed dormancy and germination of these three species. Species had significantly different responses to the treatment. In D. sophia, seeds buried at a depth of 10 cm for 60 days (55%), and seeds dry stored at 20°C for 180 days (45%) showed the highest level of germination. In M. africana, the germination percentage reached 95% when seeds buried at a depth of 1 cm were soaked in a GA3 concentration of 150 ppm. T. arvense had the lowest level of germination compared to the other species. The highest percentage of T. arvense germination was obtained in seeds treated with 150 ppm GA3. Potassium nitrate partly increased germinability in seeds of M. africana, which initially were less dormant than those of T. arvense and D. sophia