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Heavy metals are stable and persistent pollutants of the environment, and can cause both natural and anthropogenic pollution in the environment. Therefore, they are regarded as a serious risk for survival of living organisms. In order to reduce environmental problems of these metals, we need to identify natural and anthropogenic resources of them. Indeed, identifying the risk factors and awareness of the amount and effects of pollutants on the one hand, and accurate ranking of the polluting units on the other are essential steps for proper evaluation and timely and appropriate response to these risks, resulting in reduced damage due to them. The purpose of this study is to identify potential pollution sources of heavy metals of mercury, arsenic, lead, cadmium and chromium in Zanjan Province of Iran and their sampling, in order to present an index for ranking polluting units using appropriate scientific approaches like multi criteria decision making for a more accurate and quantitative assessment of risks and planning response to them in due time. The results of this study indicate that among 26 sites sampled, Mineral Processing Corporation of Iran is the most critical place of environmental risk in Zanjan province.

National project of Important Heavy Metals Identification of Iran (IHMI), following the UNDP and supported by Department of Environment of Iran (DOE), has been completed by Modares Environmental Research Center (MERC). Due to this project the pollution potential sources was investigated by overall distribution maps of any parameters that may cause the lead pollution. Then the sampling points was determined by some geo-statistical analysis and the sampling process was done according to standard methods of sampling, preserving, transferring to lab, measuring and analyzing etc through the 3 months in three phases of materials (effluent and discharges, solid waste, water, soil and sediment samples from natural sources like river etc.). After gathering the final results, overlaying the potential sources and polluted positions (according to violation of national and international standards of sampled points) by Geographic Information Systems (GIS) led the research to closing to the pollutant sources in north west provinces (Eastern Azerbaijan, Western Azerbaijan, Ardabil and Zanjan). The synthetic and natural pollution sources observed were 17 and 20 respectively. Abir River, Niroo Gostar Taban Industrial Complex and Copper Industries were the most important pollution sources in material phases of Natural, effluent and solid waste respectively.

Karanjit S Kooner,1,2 Ashika Angirekula,1 Alex H Treacher,3 Ghadeer Al-Humimat,1,4 Mohamed F Marzban,5 Alyssa Chen,1 Roma Pradhan,1 Nita Tunga,1 Chuhan Wang,1 Pranati Ahuja,1 Hafsa Zuberi,1 Albert A Montillo3,6,7 1Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX, USA; 2Department of Ophthalmology, Veteran Affairs North Texas Health Care System Medical Center, Dallas, TX, USA; 3Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX, USA; 4Department of Ophthalmology, King Hussein Medical Center, Amman, Jordan; 5Department of Electrical Engineering, University of Texas at Dallas, Dallas, TX, USA; 6Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; 7Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USACorrespondence: Karanjit S Kooner, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9057, USA, Tel +1 (214) 648-4733, Fax +1 (214) 648-2270, Email Karanjit.Kooner@UTSouthwestern.edu Albert A Montillo, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9057, USA, Email Albert.Montillo@UTSouthwestern.eduPurpose: To establish optical coherence tomography (OCT)/angiography (OCTA) parameter ranges for healthy eyes (HE) and glaucomatous eyes (GE) for a North Texas based population; to develop a machine learning (ML) tool and to identify the most accurate diagnostic parameters for clinical glaucoma diagnosis.Patients and Methods: In this retrospective cross-sectional study, we included 1371 eligible eyes, 462 HE and 909 GE (377 ocular hypertension, 160 mild, 156 moderate, 216 severe), from 735 subjects. Demographic data and full OCTA parameters were collected. A Kruskal–Wallis test was used to produce the normative database. Models were trained to solve a two-class problem (HE vs GE) and four-class problem (HE vs mild vs moderate vs severe GE). A rigorous nested, stratified, group, 5× 10 fold cross-validation strategy was applied to partition the data. Six ML algorithms were compared using classical and deep learning approaches. Over 2500 ML models were optimized using random search, with performance compared using mean validation accuracy. Final performance was reported on held-out test data using accuracy and F1 score. Decision trees and feature importance were produced for the final model.Results: We found differences across glaucoma severities for age, gender, hypertension, Black and Asian race, and all OCTA parameters, except foveal avascular zone area and perimeter (p< 0.05). The XGBoost algorithm achieved the highest test performance for both the two-class (F1 score 83.8%; accuracy 83.9%; standard deviation 0.03%) and four-class (F1 score 62.4%; accuracy 71.3%; standard deviation 0.013%) problem. A set of interpretable decision trees provided the most important predictors of the final model; inferior temporal and inferior hemisphere vessel density and peripapillary retinal nerve fiber layer thickness were identified as key diagnostic parameters.Conclusion: This study established a normative database for our North Texas based population and created ML tools utilizing OCT/A that may aid clinicians in glaucoma management.Keywords: glaucoma, optical coherence tomography angiography, deep learning

We present a hybrid device platform for creating an electrically reconfigurable metasurface formed by the integration of plasmonic nanostructures with phase-change material germanium antimony telluride (GST). By changing the phase of GST from amorphous to crystalline through Joule heating, a large range of responses from the metasurface can be achieved. Furthermore, by using the intermediate phases of GST, the metasurface can interact with the incident light in both over-coupling and under-coupling regimes, leading to an inherently broadband response. Through a detailed investigation of the nature of the fundamental modes, we demonstrate that changing the crystalline phase of the GST at the pixel-level enables an effective control over the key properties (i.e., amplitude, phase, and polarization) of incident light. This leads to the realization of a broadband electrically tunable multifunctional metadevice enabling beam switching, focusing, steering, and polarization conversion. Such a hybrid structure offers a high-speed, broadband, and nonvolatile reconfigurable paradigm for electrically programmable optical devices such as switches, holograms, and polarimeters.

Staphylococcus aureus is an important human and veterinary pathogen that causes economic loss in the poultry industry. This study aimed to compare therapeutic efficacy of 4 commonly used antibiotics in poultry on S. aureus–induced arthritis in broilers.Sixty broilers, 8 weeks of age, were assigned at random into 7 groups as follows: (1) negative control (n = 5); (2) vehicle control (n = 5); (3) sulfadiazine-trimethoprim, 250 ml/1000 l drinking water (n = 10); (4) oxytetracycline 20%, 1 mg/l drinking water (n = 10); (5) florfenicol 10%, 1/1000 v/v in drinking water (n = 10); (6) enrofloxacin 10%, 1/1000 v/v in drinking water (n = 10) and (7) positive control (n = 10).Birds in group 2 were injected with 1 ml of sterile TSB medium into the right tibiotarsal joint on d 0 while other birds (except group 1) were challenged with 1 ml of 1.2 × 1010 CFU/ml suspension of S. aureus bacteria.Antibiotic therapy was started from d 4 post challenge and continued for 5 d. At the end, birds were weighed and clinical severity of arthritis was determined. After blood collection, birds were slaughtered and tibiotarsal and hip joints were evaluated grossly. The content of inflammatory exudates of tibiotarsal joint and the degree of femoral head necrosis were recorded. Mucin clot test and histopathological evaluation were performed on right tibiotarsal joint. Serum interleukin 6 was also assayed.Sulfadiazine-trimethoprim had higher therapeutic efficiency with regard to most of the assayed criteria, whereas none of the antibiotics significantly affected femoral head necrosis and body weight. These data will help clinicians to have better antibiotic choice in field conditions. [ABSTRACT FROM PUBLISHER]

Background & Aims: Ventilator associated pneumonia is one of the most common hospital infections. We investigated the prevalence and microbial agents and outcome in patients who was admitted to the medical intensive care unit of Rohani Hospital. Materials & Methods: This prospective descriptive study is performed in one year from October 2009 to October 2010 in MICU patients that their tracheal intubation time was more than 48 hours. Patients that died in less than 24 hours were excluded. Diagnosis of VAP was based on CPIS. The type of microbes found in the laboratory according to standard biochemical methods. Age and Sex, cause of admission, GCS, duration of mechanical ventilation, length of stay ,APACHE score and their outcome related to patients with VAP and without VAP were recorded. The results were statistically analyzed with SPSS software, and P less than 0.05 was considered significant. Results: Totally, 134 patients were enrolled. VAP developed in 37 patients (27.6%), in which 18 patients died (48.6%). In 100 cases without VAP, 42 cases died (43.2%). Average length of stay in VAP and Non-VAP was 34.86 days and, 9.48 days respectively. The incidence of VAP was 21 cases per 1,000 days of mechanical ventilation. Conclusion: Our study has shown that the incidence of VAP in the MICU is somewhat high, and it requires immediate attention due to prolonged hospitalization and increased mortality. [ABSTRACT FROM AUTHOR]

Background: We sought to evaluate the routine echo-Doppler screening of carotid artery stenosis in patients undergoing coronary artery bypass grafting. Methods: A total of 2179 consecutive patients who underwent coronary artery bypass grafting alone or with other cardiac surgery at Tehran Heart Center, Tehran-Iran, between January 2005 and January 2006 were included in this retrospective study. Carotid Doppler was performed for 1604 (81.48%) of these patients. Results: The patients' age ranged between 20 and 84 years (mean: 58.33, SD: 10.08 years). Of the 1604 patients studied, 1186 (73.9%) were men, 592 (36.9%) had diabetes, 598 (37.3%) were smokers, and 194 (12.1%) cases had significant left main stenosis. Twenty-one (1.3%) patients had significant carotid stenosis (> 60% stenosis), which constituted 0.9% of all the bypass surgery candidates. Post-operative cerebrovascular accident was not detected in any of the patients with significant carotid stenosis, but cerebrovascular accident occurred in 22 (1.4%) of the patients without carotid stenosis. Magnetic resonance angiography (MRA) was conducted in 15 patients. In our univariate analysis, female gender (p value = 0.023), hypertension (p value = 0.055), peripheral vascular disease (p value < 0.001), and age (p value = 0.001) were significant in the development of carotid stenosis. Conclusion: Pre-operative duplex carotid screening seems to be necessary in patients when there is hypertension, peripheral vascular disease, female gender, and advanced age. [ABSTRACT FROM AUTHOR]

Acute aortic dissection (AAD) is the most frequent catastrophic event of the aorta; it occurs nearly three times as frequently as the rupture of abdominal aortic aneurysm. Sixty percent of dissection cases are classified as proximal or type A and 40% as distal or type B, according to the Stanford Classification. The most frequent causes of death in acute type B dissection are aortic rupture and malperfusion syndrome. We herein review recent data suggesting different management modalities of type B aortic dissection, including medical, surgical, and endovascular treatments. Although medical therapy is still the standard approach in uncomplicated cases, there are subgroups of patients who may benefit from endovascular management. Endovascular techniques or surgery are valuable options for complicated cases. Hybrid suites, multidisciplinary approaches, and good imaging techniques can be considered as the key to success in this regard. [ABSTRACT FROM AUTHOR]

Background: Atrial myxomas are the most common cardiac neoplasms. They consist of 2 macroscopic features of solid, papillary, and myxoma cells in abundant mucopolysaccharide stroma in microscopic examination. The majority of patients may experience central or peripheral embolization, intracardiac obstruction, or constitutional symptoms. We sought to investigate the clinical presentation and pathological features of atrial myxomas in the population that underwent cardiac surgery at our institution. Methods: Nineteen patients undergoing atrial myxoma excision were collected prospectively from the 18,300 patients who underwent cardiac surgery between January 2001 and June 2008 at Tehran Heart Center. Results: Our study population consisted of 8 men and 11 women with a mean age of 54.05 ± 7.33 years. All of the cases had left atrial tumors. The solid myxoma group (79%) was comprised of 8 females and 7 males, while papillary myxoma (21%) was detected in 3 females and 1 male. In our study, 6 patients (32%) had hypertension (HTN), 4 (21%) had diabetes mellitus, and 5 (26.3%) had hyperlipidemia. Smoking and opium addiction were detected in 6 (32%) and 3 (16%) patients, respectively. Dyspnea was the most prevalent presenting symptom occurring in 12 patients (63%), followed by chest pain in 7 (37%), and neurological symptoms in 5 (26%). Hypertension was more prevalent in the patients with neurological symptoms than in those without them (P=0.046). Five patients were anemic, and 5 cases had leukocytosis. Anemia was detected in 75% of the patients with papillary tumors compared to 13.3% of the patients with solid tumors (P=0.037). Thrombocytosis was detected in 1 patient. Plasma cells infiltration were found in 1 papillary and 14 solid tumors. Neutrophils were detected in 9 solid and 1 papillary tumor. Three solid tumors revealed mineralized circumscribed nodules (Gamna-Gandy bodies). In patients with chest pain, the neutrophil count in the tumor tissue, not in the blood, was not significantly different from that observed in patients without chest pain (85.7% vs. 33.3%, respectively, P=0.057). Discussion: Our data demonstrated the histological features of atrial myxomas correlated to some of the patients' clinical findings. This study identifies for the first time the correlation between HTN and CNS symptoms in atrial myxoma. The presence of these findings could be due to the production of different mediators such as interleukins. However, further studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the impact of diabetes mellitus (DM) on peripheral vascular disease (PVD) in patients with coronary artery disease (CAD). Methods: A total of 13702 consecutive patients who underwent coronary artery bypass grafting (CABG) at Tehran Heart Center between January 2002 and March 2007 were included in this study. The demographic data, PVD, and outcome of these patients were reviewed. CABG patients before surgery were detected for PVD (stenosis >=70% in the abdominal aorta; renal, carotid, and iliac arteries; or any other peripheral vascular system) with physical examination and past medical history. The suspected cases of PVD were, thereafter, confirmed via Doppler sonography or invasive angiography. Results: This study recruited 4344 diabetic patients (mean age 59.30±8.7 years) and 9358 non-diabetic patients (mean age 58.42±9.9 years). The diabetics were significantly older and had a higher incidence of PVD (2.7% vs. 1.8%), female gender, hypertension, renal failure, smoking, and dyslipidemia than the non-diabetics (P<0.05). There was no significant difference between the two groups with regard to family history and left main disease. Also, the mean ejection fraction (EF) was 48.85%±10.4 and 49.35%±10. In the patients with and without DM, respectively; and the difference was significant (P=0.008). The in-hospital mortality rate (mortality over a 30-day post-operative period) was 1.8% in the diabetics and 0.7% in the non-diabetics (P<0.001). In the multivariate analysis, PVD, left main disease, age, female gender, and EF were significant in the development of mortality amongst the diabetic patients with a respective odds ratio of 4.17, 5.54, 1.03, 2.86, and 0.95 (P<=0.050). In the multivariate logistic regression analysis, PVD was significantly higher in the diabetics than in those without DM (OR=1.283, 95% CI: 1.001- 1.644; P=0.049). In the diabetic patients, carotid (1.13% vs. 0.83%), subclavian (0.05% vs. 0.02%), femoral (0.18% vs. 0.09%), renal (0.62% vs. 0.25%), and tibialis (0.16% vs. 0.06%) arteries had a higher incidence of stenosis than those in the non-diabetics. Conclusion: We conclude that in diabetic patients with concomitant CAD, special attention must be directed towards the diagnosis of PVD using physical examination, Doppler sonography; and where needed, CT-angiography or invasive angiography. Also, in risk assessment, the presence of PVD should be strongly considered for CAD patients. [ABSTRACT FROM AUTHOR]

Behcet's disease is a multisystem disorder and classified as 'vasculitic syndrome with a wide variety of clinical manifestations.' Cardiac involvement is very rare but can occur with different presentations including: pericarditis, cardiomyopathy, endocarditis, endomyocardial fibrosis, intracavitary thrombosis, and coronary artery disease. Great vessel involvement is more common. Recurrent Phlebitis, commonly involving large vessels (superior vena cava, inferior vena cava, hepatic veins) and cerebral veins are the sole presentation in this regard. Arterial involvement is expressed by aneurysm or pseudoaneurysmal formation. Due to the wide variety of cardiovascular manifestations and the resulting high mortality, cardiac surgeons should be familiar with this disease. In this paper we review the articles and introduce our four cases presenting with aneurysm of ascending aorta with free aortic insufficiency, aneurysm of descending aorta, pulmonary artery aneurysm, and pseudoaneurysm of aortic arch. [ABSTRACT FROM AUTHOR]

This study investigated the association between lung cancer and waterpipe smoking, which is an emerging global public health concern. Multicentre case-control study. This study included 627 cases and 3477 controls from the Iranian Study of Opium and Cancer (IROPICAN) study, which was conducted between 2017 and 2020. One frequency-matched control for each lung cancer patient was selected by age, gender and residential place; however, this study used controls of four cancer types in the analyses. The multivariable logistic regression model estimated the odds ratio (OR) and 95% confidence intervals (CIs). Additional analyses were performed among 181 lung cancer cases and 2141 controls who were not cigarette smokers or opium or nass/pipe users. The odds of lung cancer were higher among waterpipe smokers than never-smokers (OR = 1.3, 95% CI: 1.0–1.7). Results showed a higher OR of lung cancer for those who smoked the waterpipe daily (OR = 2.1, 95% CI: 1.4–3.0), smoked more than two heads per day (OR = 2.7, 95% CI: 1.8–4.0), had smoked for >20 years (OR = 1.9, 95% CI: 1.3–2.7), smoked more than 20 head-years (OR = 2.8, 95% CI: 1.9–4.1) and initiated smoking before the age of 30 years (OR = 1.7, 95% CI: 1.1–2.5). The association was only statistically significant for squamous cell carcinomas (OR = 1.8, 95% CI 1.2–2.7). Furthermore, this study observed a higher OR of lung cancer among exclusive waterpipe smokers (OR = 2.3, 95% CI: 1.6, 3.5). Waterpipe smoking was associated with an increased risk of lung cancer. The association was stronger with higher frequency, duration and intensity of exposure to waterpipe smoking. The association increases in exclusive waterpipe smokers, which is likely due to controlling for residual confounding by cigarette smoking and opium consumption, and higher exposure levels in this subpopulation. [ABSTRACT FROM AUTHOR]

The main purpose of this research was to study of relation between organizational health and organizational entrepreneurship in the University of Tehran. The main research instrument was an electronic questionnaire, which consisted of two parts: organizational health and organizational entrepreneurship. The statistical population of the research consisted of all staffs of in the University of Tehran. Using Cochran’s sampling formula, 230 staffs were selected as research sample. SPSS win 18 were used for data analyzing. Findings showed a positive and significant relationship (in level 1%) was between all of the organizational health components with organizational entrepreneurship. The results of multiple regressions also showed that among eight components of organizational health, four components included efficiency, unity and adaptability, innovation and participation in decision-making could explained 69% of total variance of organizational entrepreneurship