Chromium-based polypyrrole/MIL-101 nanocomposite as an effective sorbent for headspace microextraction of methyl tert-butyl ether in soil samples

The performance of headspace solid-phase microextraction (HS-SPME) was upgraded by easy and low-cost preparation of a new nanocomposite fiber. A polypyrrole/chromium-based metal–organic framework, PPy@MIL-101(Cr), nanocomposite was electrochemically synthesized and simultaneously coated on a steel wire as a microextraction sorbent. The morphology and chemical structure of the prepared nanocomposite was characterized by Fourier-transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) techniques. The microsorbent was used for sampling of methyl-tert-butyl ether (MTBE) in solid samples, through an HS-SPME sampling strategy, followed by GC-FID measurement. The optimal experimental conditions, including extraction temperature, extraction time, and GC desorption conditions, were evaluated and optimized. The proposed procedure showed good sensitivity (limit of detection was 0.01 ng·g−1) and precision (relative standard deviation was 8.4% for six replicated analyses). The calibration curve was linear over the range of 5–40,000 ng·g−1, with a correlation coefficient of 0.994. The limit of quantification was 0.4 ng·g−1. The fabricated fiber exhibited good repeatability and reproducibility for the sampling of MTBE, with average recovery values of 88–114%. The intra-fiber and inter-fiber precisions were found to be 8.4% and 19%, respectively. The results demonstrated the superiority of the PPy@MIL-101(Cr)-coated fiber in comparison with handmade (polypyrrole, PPY) and commercial fibers (polyacrylate, PA; polydimethylsiloxane, PDMS; and divinylbenzene/carboxen/polydimethylsiloxane, DVB/CAR/PDMS) for the analysis of solid samples. The developed method was successfully employed for the analysis of MTBE in different soil samples contaminated by oil products

Liquid-phase microextraction of polycyclic aromatic hydrocarbons: A review

Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic compounds comprised of two or more fused benzene rings, which arise from the incomplete combustion of organic materials. These compounds have been of concern as carcinogens and mutagens for the past 50-60 years. Lately, they are also receiving attention as endocrine-disrupting chemicals. Therefore, proper analytical methods are required for sampling and analyzing these compounds. In response to problems associated with the conventional methods like solid-phase extraction (SPE) and liquid-liquid extraction (LLE), many studies have focused on the miniaturization of different sample preparation techniques. In this regard, the use of different types of liquid phase microextraction (LPME) techniques has increased significantly during the recent few decades. LPME techniques are advantageous because they use single-step sample preparation and have shown a greater sensitivity, selectivity, and efficiency than the conventional methods. In addition, these techniques have good potential for automation, to reduce the time and cost of analysis. This review focuses on the most important configurations of LPME including single‐drop microextraction (SDME), hollow-fiber liquid-phase microextraction (HF-LPME), and dispersive liquid-liquid microextraction (DLLME) techniques used for the sampling and determination of PAHs in different samples, along with their cons and pros, as well as their prospects

Mutual interaction of salinity and dietary protein level on growth, survival and body composition of narrow clawed cray fish (Astacus leptodactylus)

In this study Astacus leptodactylus were tested for 8 week with three practical diets containing three crude protein (30, 35 and 40%) and isoenergetic level (370kcal/100 g) in fresh water and brackish water of Caspian Sea. In this test, 6 treatments were used with three replicates in 18 fiberglass tank (110 liter). Each tank had 5 narrow clawed Cray fish (mean (±SD) individual weight=17±2.3g) and totally 90 clawed Cray fish were stocking. Result indicates mean weight of Cray fish in fresh water and brackish water were 14.82 and 12.73, respectively, that were significantly different. The highest survival occurred in interaction between protein (30%) and salinity (0) (95.55%) and lowest survival occurred in protein 40 – salinity (12) that were significantly different. The highest specific growth rate (SGR), weight gain (WG), Protein Efficiency Ratio (PER), Net Protein Utilization (NPU) and lowest Feed Conversion Ratio (FCR), demonstrated that dietary (protein 30% and fresh water) which had no significantly differences. Result of this study showed that the highest protein of body composition were in practical diet containing 30% protein and 0 salinity (freshwater) that were significantly different with other treatment

Evaluation of different dietary protein and energy levels on growth performance and body composition of narrow clawed crayfish (Astacus leptodactylus)

Nine practical diets containing increasing percentages of crude protein (CP) and energy (30%, 35%, 40% and 300kcal/100g, 370kcal/100g and 450kcal/100g) were fed to narrow clawed crayfish (mean individual weight=17±2.3 g) during an 8 week feeding trial. Weight Gain, Feed conversion ratio (FCR), Protein Efficiency Ratio (PER), Net Protein Utilization (NPU), Daily Food Consumption (DFC) and body composition of tail-muscle meat of narrow clawed crayfish were determined. At the conclusion of the experiment, comparing the growth parameters in response to interaction between protein and energy levels demonstrated that dietary number 2 (30/370) resulted in higher WG, NPU, PER, and the lowest FCR whereas dietary number 3 (30:450) showed higher SGR and DFC. Comparison of the body composition results indicates the greatest amount of protein absorption in diet number 2 (30/370). Results from this study indicate that narrow clawed crayfish can be fed a practical diet containing 30% protein and 370 Kcal/100gr. Reducing CP levels in narrow clawed crayfish diets may help reduce operating costs and thereby increase producers’ profits

The Relationship between Environmental, Cultural and Chronological Factors with the Frequency, Cause and Type of Burn Injuries Admitted to the Trauma and Burn Center Motahari Hospital, during the Years 2007to 2011

Background:One of the most important health associated problem are events, which burns considered the most common of them. To prevent burn and reduce the complication and mortality rate, accurate information of epidemiology of burn is essential for planning properly.This study was conducted to determine the relationship between environmental and cultural factors and the type, cause and extent of burn injuries admitted to the trauma and burn center of Motahari hospital during 1386 to 1390.Methods: In this routine data base study, we recruited all burned patients whichreferred to trauma andburncenter of ShahidMotahari hospital between 2007 and 2011. Mainvariables includingeconomic conditions, season ofoccurrenceof the accident,the accident tocurriedonspecial occasions, yearof accident, accidentstatuson holidays, type of injury, cause of injury, injuryseverity, burnarea, anddemographic variables such asage and gender were entered in checklist from patient’s documents.Collected data were entered into softwareSPSS version 11 and were analyzed.Results:5511 patients were admitted to Motahari hospital during the April of 1386 to the end of 1390, from which 1448 (26.3%) cases were female and 4063 (73.7%) male. The mean age of subjects was 28.47 (SD=1.88).There was significant difference between different gender and etiology, so that men were burned more by oil, gasoline and diesel fuel rather than women.There was significant difference about the number of burned cases by the flame at different seasons of the year. Average number of people burned by gas cylinders,electricity,caraccident,bitumen was significantly different in different seasons.Conclusion:There were significant differences about burn injuries due to the gas cylinders,bitumen,electricity and car accidents in different seasons and months.To inform burn centers, principalship of these data increases their ability to manage populated and harmful days. According to the higher rate of explosive burn injury in the last month of the year producing harmless explosive materials can be so effective to support patients lives

Ischemic heart disease risk factors in lead exposed workers: Research study

Background: Review of other epidemiological studies reveal inconsistent results of relationships between high blood lead level and risk of hypertension, hyperlipidemia and hyperglycemia. In this study we wanted to find if there is a relationship between blood lead level and these ischemic heart disease risk factors. Methods. This cross-sectional study was conducted in a battery recycling plant, and 497 male workers with the mean age of 41.7 (±6.50) years were recruited from all over the plant (those from the products and maintenance sections were classed as "high lead exposed group" and those from amongst the office, laboratory, security services and food services sections as "low lead exposed group"). Personal information such as demographics and work history was obtained through a questionnaire. Mean (±Standard deviation) for quantitative variables, Frequency (Percent) for qualitative variables, and Odd's ratio (OR) with 95 confidence interval (95 CI) for estimating the effect of blood lead level on lipid profiletriglyceride (TG), cholesterol(CHOL), low density lipoprotein - Cholesterol(LDL-C),high density lipoprotein -Cholesterol(HDL-C), hypertension(HTN) and fasting blood sugar (FBS) level. Logistic regression modeling was used for multivariate analysis and adjusting the effect of different variables (age, body mass index(BMI), eating habits, cigarette smoking). Results: The mean Blood Lead Level (BLL) was >40 μg/dl in 281 (56.6%) subjects, �40 μg in 216 (43.4%) subjects and the mean BLL was 43.3 μg/dl (n = 497). The mean job experience involving lead exposure was 13 years. There was no significant correlation between BLL and FBS (p = 0.68), between BLL and TG (P = 0.32), between BLL and HDL-C (p = 0.49), between BLL and LDL-C (p = 0.17), between BLL and CHOL(p = 0.96), between BLL and systolic blood pressure (p = 0.12). The adjusted Odd's ratio for the effect of BLL >40.0 μg/dl on diastolic blood pressure was1.03 (95% CI: 1.01-1.05) with p = 0.05. Conclusion: This study showed an association of high BLL with diastolic blood pressure but not with TG, FBS, and HDL-C, LDL-C and CHOL. This result persisted even after adjustment was made for age, BMI and job experience, smoking and eating habits. Attention to health-protective policies, individual behavioral changes and regular periodic medical examination with focus on diastolic blood pressure in lead exposed workers is likely to decrease the public health burden of ischemic heart disease. © 2013 Ghiasvand et al.; licensee BioMed Central Ltd

Economic burden of HIV/AIDS Infection in Iran : a modelling approach

Background: The Human Immunodeficiency Viruses/Acquired Immunodeficiency syndrome HIV/AIDS is a leading cause of mortality and morbidity in Low-and-Middle-Income-Countries (LMICs). It might potentially lead to an economic burden on the health system. There is no certainty about the prevalence of HIV/AIDS in Iran. To the best of our knowledge, there is a lack of economic evidence in the country. Therefore, this study aims to estimate the cost of illness of HIV/AIDS infection in Iran. Methods: We applied a societal perspective to capture the direct and indirect costs attributed to HIV/AIDS in Iran. We used data for age-standardized prevalence produced by the country HIV/AIDS Surveillance System for 2018. The study estimates both direct and indirect costs for a hypothetical cohort of the Iranian adult population (here equates to all registered cases with Surveillance System). For mitigating the uncertainty around the estimations, we have used an optimistic and pessimistic analysis. Results: The base case scenario showed that total direct costs and indirect costs attributed to the HIV/AIDS infection were US$7,946,530 and US$ 1,288,586 at the end of 2018. Also, the total cost is 8,785,116 US$. Conclusions: Direct costs have formed approximately 85% of total costs. The policymakers and planners should consider that these costs are only related to diagnosed or registered infected populations. These costs will be raised dramatically with increasing the diagnosed patients

Molecular identification and antibiotic resistance pattern of actinomycetes isolates among immunocompromised patients in Iran, emerging of new infections

Recent advancements in DNA-based approaches have led to the identification of uncommon and rare bacterial pathogens. In this study, by utilizing a DNA-based approach, a total of 1043 clinical specimens were processed for the identification of actinobacteria targeting the 16S rRNA and gyrB genes. Drug susceptibility testing was also conducted using micro-broth dilution and PCR. Two isolates of Nocardia flavorosea and Rhodococcus erythropolis were reported for the first time in Iran. Also, Nocardiopsis dassonvillei, Streptomyces olivaceus, and Streptomyces griseus were reported for the first time in Asia. Infections caused by Nocardia caishijiensis and Prauserella muralis have also been reported in this study. The first Asian case of pulmonary infection caused by Nocardia ignorata and the first global case of brain abscess caused by Nocardia ninae and Nocardia neocaledoniensis have been reported in this study. Overall 30 isolates belonging to 6 genera (Nocardia, Streptomyces, Rodoccoccus, Nocardiopsis, Rothia, and Prauserella) were detected in 30 patients. All 30 isolates were susceptible to amikacin and linezolid. Three isolates including Nocardia otitidiscaviarum (n = 2) and Nocardia flavorosea (n = 1) were resistant to trimethoprim-sulfamethoxazole which were the first trimethoprim-sulfamethoxazole resistant clinical actinomycetes in Iran. Isolation of rare species of actinomycetes particularly Nocardia spp. requires urgent action before they spread clinically particularly among immunocompromised patients. © 2021, The Author(s)