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A polyacrylonitrile–polyamide 6/polyaniline (PAN–PA6/PANI) doped membrane was prepared using dual spinneret simultaneous electrospinning of PAN and PA6 and in situ polymerization of aniline at low temperature. The performance of the membrane was investigated in separation of non-surfactant and different surfactant oil/water emulsions like SDS, Tween 80 and Span 80. The field emission electron microscopy (FESEM) and energy dispersive X-ray (EDS) results revealed that PAN–PA6 nanofibers are coated uniformly with PANI. According to the atomic force microscopy (AFM) maps, the surface roughness of the fabricated membrane was increased from 51 to 83 after coating, which can improve the membrane flux and oil rejection. The stress–strain test displayed that PA6 improved the PAN mat tensile strength from 3.88 to 11.86 MPa. Post treatment of PAN–PA6/PANI with doping in HCl 1 M can improve the membrane hydrophilicity and separation efficiency. The effect of the polymerization time on the membrane porosity and pore volume was investigated. The optimum time of polymerization where the membrane has high permeate flux (326 Lmh) and oil rejection (97.8%) was found to be 60 min for non-surfactant (hexane/water) emulsion separation. The performance of the membrane was studied for separation of petroleum ether, gasoline and gas oil emulsions in water. The reusability and chemical resistance of the membrane in harsh conditions were investigated.

Objectives. The future workshop (FW), as a participatory ergonomics approach, is used to change the actual situation of a system into a preferable one. This study was conducted at a major hospital to identify ergonomic problems and provide appropriate solutions for improving working conditions using the FW technique. Methods. Twenty-five mid-level managers of the hospital participated in a 2-day FW. In the critique phase, the ergonomic problems were thoroughly discussed. After brainstorming followed by structuring and grouping of ideas, 75 ergonomic problems were identified and classified into four groups. Solutions and action plans were proposed to improve working conditions. Results. There were nine problems in the personnel-managerial group. Eighteen action plans were proposed to fix them. Stressful occupational factors were the worst problem in this group. Five problems were characterized in the physical space group and 10 action plans were presented. Seven problems were detected in the equipment group, for which 13 action plans were presented. In the welfare group, six problems and 12 action plans were presented. Conclusion. The results revealed that the FW was an appropriate method to find ergonomic bottlenecks in the hospital and a good basis for devising ergonomic interventions.

Wound healing is a varied and complex process designed to restore normal skin structure, function, and appearance in a timely manner. To achieve this goal, different immune and biological systems participate in coordination through four separate steps, including homeostasis, inflammation, proliferation, and regeneration. Each step involves the function of different cells, cytokines, and growth factors. However, chronic ulcers, which are classified into three types of ulcers, namely vascular ulcers, diabetic ulcers, and pressure ulcers, are not able to heal through the mentioned natural stages. This, in turn, causes mental and physical problems for these people and, as a result, imposes high economic and social costs on the society. In this regard, using a system that can accelerate the healing process of such chronic wounds, as an urgent need in society, should be considered. Therefore, in this study, the innovations of drug delivery systems for the healing of chronic wounds using hydrogels, nanomaterials, and membranes are discussed and reviewed.

As a hydrophilic renewable polymer, starch has been widely used in biocompatible plastics as a filler for more than two decades. The present study aimed at investigating the effects of polyethylene glycol (PEG), as a plasticizer, on the physicochemical properties of a hybrid composite—polylactic acid (PLA) and thermoplastic starch (TPS). A solvent evaporation process was adopted to gelatinize the starch and disparate PEG contents ranging from 3 to 15 wt.% (with respect to the sample weight) were examined. It was revealed that the increase in the PEG content was accompanied by an increment in the starch gelatinization degree. Referring to the microstructural analyses, the TPS/PLA mixture yielded a ductile hybrid composite with a fine morphology and a uniform phase. Nevertheless, two different solvents, including acetone and ethanol, were used to assess if they had any effect on the hybrid’s morphology, tensile strength and thermal properties. It was found that ethanol culminated in a porous hybrid composite with a finer morphology and better starch distribution in the PLA structure than acetone. As the result of PEG addition to the composite, the crystallinity and tensile strength were decreased, whereas the elongation increased. The hydrolytic degradation of samples was assessed under different pH and thermal conditions. Moreover, the microbial degradation of the PLA/TPS hybrid composite containing different PEG molar fractions was investigated in the soil for 45 days. The rate of degradation in both hydrolytic and biodegradation increased in the samples with a higher amount of PEG with ethanol solvent.

BACKGROUND: Studies have demonstrated that upper extremity musculoskeletal disorders (UEMSDs) are highly prevalent among weavers. In Iran, little information is available regarding the prevalence of MSDs and their causal risk factors among hand-woven shoe workers. This cross-sectional study aimed to determine the prevalence of UEMSDs and to identify risk factors associated with UEMSDs symptoms among 586 Iranian hand-woven shoe workers. METHODS: The data were collected using the Nordic Musculoskeletal Questionnaire and by direct observation of working postures via the Rapid Upper Limb Assessment (RULA) technique to determine ergonomic risks. RESULTS: The prevalence of MSDs symptoms was high among the hand-woven shoe workers. The mean RULA grand score of 6.3 indicated that in most cases the workers’ postures at their workstations needs to be investigated and changed immediately to prevent musculoskeletal injuries. The highest prevalence rates of MSDs were observed in the shoulders, wrists and arms. The result of multiple logistic regression modeling showed that risk factors associated with UEMSD symptoms were job experience, daily working hours, job satisfaction, working posture, work pressure, and discomfort at workstation, as well as individual factors, such as age, gender, BMI, material status, working conditions, education level, and lack of regular sport/physical activities. CONCLUSIONS: The findings of the present study emphasize that any interventional program in this industry has to focus on improving working conditions particularly by designing ergonomics-oriented workstations and hand tools.

Lupus is a common autoimmune disorder with the potential to affect all organ systems. Lupus enteritis is a rare complication that is seen in a subset of patients that present with gastrointestinal symptoms. Its diagnosis commonly involves imaging, showing bowel wall edema as the target sign and vascular engorgement of bowel vessels as the comb sign on CT scans. These findings can help guide the diagnosis, but they are nonspecific and are also found in other conditions that cause bowel wall ischemia. These symptoms are reversible if treated with immunosuppressants. Unfortunately, recurrence is common in lupus enteritis and perforation needs to be ruled out on presentation. In this report, we present the case of a patient with known lupus who was diagnosed with lupus enteritis on imaging and was treated with immunosuppressants. The patient's symptoms resolved subsequently. Our case highlights the fact that the appropriate diagnosis and management of this condition require physical exams, labs, and imaging.

Cerebral palsy (CP) is a neuro-developmental disorder. Spastic CP is the most common type of CP and is characterized by contractures of the extremities. Selective Percutaneous Myofascial Lengthening (SPML) is a minimally invasive procedure practiced by a handful of physicians in the US, and it decreases contractures and increases the range of motion in individuals with spastic CP. This study wanted to examine if there was an association between CP severity, socioeconomic status, and reoperation rates. This study used electronic medical records (EMR) to include 626 patients with spastic CP who had surgeries between January 2006 and December 2012. The zip codes from the EMR were used to determine the inflation-adjusted mean income and educational qualification (a high school education or higher) of the community via the US Census Bureau. Disease severity before the initial surgery was determined by using the functional mobility scale in the EMR to compute the Gross Motor Function Classification System (GMFCS) level. Then the data was graphed and averages were taken for the reoperation versus the no-reoperation populations, and Student's t-tests were run to determine statistical significance. The data showed that communities with higher education and income tended to reoperate more often. The higher number of reoperations in affluent communities could mean that either more affluent communities are better educated and know the benefits of bringing their children back for reoperation or that they require further education about physical therapy after the initial surgery to decrease the incidence of reoperation. This retrospective study is a level 2 study looking at the socioeconomic and educational backgrounds and disease severity and their association with reoperation rates.

It has been estimated that there are greater than 100,000 individuals in the US with sickle cell disease. Hepatic sequestration is a known sequelae of sickle cell disease that rarely leads to extreme hyperbilirubinemia (total serum bilirubin greater than 20 mg/dl). Our 26-year-old male patient, though compliant with regular transfusion exchanges, presented with hepatic sequestration, with minimal symptoms and hyperbilirubinemia up to approximately 40 mg/dl. The severity of asymptomatic hepatic sequestration seen in our patient has never been reported in the literature. This mandates a low threshold to screen for sickle cell complications and promptly treating these patients admitted to the hospital with exchange transfusions.

Achalasia is an uncommon disease that occurs due to inability of lower esophageal sphincter from relaxing, leading to dysphagia to liquids and solids. Clues to this diagnosis include: failed treatment with proton pump inhibitors, and changes on imaging studies including chest X-ray and barium esophagogram. Ultimately it is a diagnosis made on esophageal manometry. Swallow-induced syncope has been known in patients with achalasia for almost three centuries. Here we present the case of a patient with achalasia and a non-swallowing syncopal episode. To our knowledge and extensive search, there has been no report of a similar case.

HMG-CoA reductase inhibitors (statins) are one of the most widely used medications in the primary care setting, and like any medications they have many side effects. The common ones include myalgias and rare ones include dermatomyositis. Here we present the case of atorvastatin-induced dermatomyositis with an unfortunate progression. This mandates a low threshold for first contact doctors to screen their patients for new-onset muscle weakness and rash after starting a statin recently, like our patient who had started atorvastatin several months before. This case adds to the previously reported cases and provides further evidence for statins being triggers of immune-mediated disease. The appropriate management of this condition requires a collaborative effort involving clinical judgment, laboratory testing, and imaging.

Due to lower clinical significance, the management of Dieulafoy and Dieulafoy-like lesions is less commonly reported than the management of their impending venous equivalent, variceal bleeding. Though Dieulafoy and Dieulafoy-like lesions are often benign, they can become life-threatening in certain clinical scenarios, especially with substantial changes in hemodynamic blood flow, which results in hemorrhage. Post-procedural hemodynamic blood flow should be carefully monitored in patients who receive procedures that drastically alter hemodynamic flow pressures. Factoring in the presence of Dieulafoy and Dieulafoy-like lesions might deepen the complexity of an intuitive surgical or interventional procedure for an experienced operator, and should, therefore, involve the cooperative effort between surgical, interventional, and diagnostic services to appropriately manage the patients. The case we present demonstrates the dire consequences of a routine splenectomy when a considerable change in hemodynamic pressure across benign Dieulafoy-like lesions occurs in a patient with both splenic artery and venous thrombosis.

Intravascular Ultrasound (IVUS) is an intra-operative imaging modality that facilitates observing and appraising the vessel wall structure of the human coronary arteries. Segmentation of arterial wall boundaries from the IVUS images is not only crucial for quantitative analysis of the vessel walls and plaque characteristics, but is also necessary for generating 3D reconstructed models of the artery. The aim of this study is twofold. Firstly, we investigate the feasibility of using a recently proposed region detector, namely Extremal Region of Extremum Level (EREL) to delineate the luminal and media-adventitia borders in IVUS frames acquired by 20 MHz probes. Secondly, we propose a region selection strategy to label two ERELs as lumen and media based on the stability of their textural information. We extensively evaluated our selection strategy on the test set of a standard publicly available dataset containing 326 IVUS B-mode images. We showed that in the best case, the average Hausdorff Distances (HD) between the extracted ERELs and the actual lumen and media were $0.22$ mm and $0.45$ mm, respectively. The results of our experiments revealed that our selection strategy was able to segment the lumen with $\le 0.3$ mm HD to the gold standard even though the images contained major artifacts such as bifurcations, shadows, and side branches. Moreover, when there was no artifact, our proposed method was able to delineate media-adventitia boundaries with $0.31$ mm HD to the gold standard. Furthermore, our proposed segmentation method runs in time that is linear in the number of pixels in each frame. Based on the results of this work, by using a 20 MHz IVUS probe with controlled pullback, not only can we now analyze the internal structure of human arteries more accurately, but also segment each frame during the pullback procedure because of the low run time of our proposed segmentation method., Comment: 15 pages, 5 figures, published in Elsevier Ultrasonics

This article analyzes the movies produced in the two decades prior to the 1979 Revolution in Iran. It argues that these films influenced a cultural transformation we call a ‘quiet revolution.’ The ...

This article studies materials published in the Bonyad Monthly, a journal sponsored by the Pahlavi state. It was published for two years (1977–78), just prior to the 1979 Revolution in Iran. Bonyad Monthly’s mission was to engage in the ongoing intellectual debates at the time in Iran’s encounter with modernity. It primarily published articles, interviews and translations, with the aim of exposing the cultural and moral perils of modern western culture. The writers of Bonyad Monthly cast the modern world as morally soulless, culturally debased, politically imperial and arrogant. The Journal also depicted Iranian culture as the mirror image of the modern west, and part of the rising “Eastern spiritual” resurrection. More specifically, Bonyad Monthly helped invert and de-politicize the notion of Gharbzadegi (Westoxification). The Gharbzadegi discourse, a powerful rhetorical device, had been used by oppositional intellectuals to condemn the Pahlavi modernization programme. It was now ironically claim...

This paper examines the elite discourse on technology in Iran. The paper examines how concepts such as progress (taraqqi), civilization (tamaddon), and modernity (tajaddod), and later notions such as backwardness (‘aqab-mandegi), authenticity (isalat), and “Westoxication” (gharbzadegi) have articulated an elite discourse of technology in Iran. The paper argues that a utilitarian view of technology dominates the elite discourse. Although intellectuals view modernity with ambivalence, their outlook on technology remains utilitarian in their discourse of authenticity.

A Fully Convolutional Network (FCN) based deep architecture called Dual Path U-Net (DPU-Net) is proposed for automatic segmentation of the lumen and media-adventitia in IntraVascular UltraSound (IVUS) frames, which is crucial for diagnosis of many cardiovascular diseases and also for facilitating 3D reconstructions of human arteries. One of the most prevalent problems in medical image analysis is the lack of training data. To overcome this limitation, we propose a twofold solution. First, we introduce a deep architecture that is able to learn using a small number of training images and still achieves a high degree of generalization ability. Second, we strengthen the proposed DPU-Net by having a real-time augmentor control the image augmentation process. Our real-time augmentor contains specially-designed operations that simulate three types of IVUS artifacts and integrate them into the training images. We exhaustively assessed our twofold contribution over Balocco’s standard publicly available IVUS 20 MHz and 40 MHz B-mode dataset, which contain 109 training image, 326 test images and 19 training images, 59 test images, respectively. Models are trained from scratch with the training images provided and evaluated with two commonly used metrics in the IVUS segmentation literature, namely Jaccard Measure (JM) and Hausdorff Distance (HD). Experimental results show that DPU-Net achieves 0.87 JM, 0.82 mm HD and 0.86 JM, 1.07 mm HD over 40 MHz dataset for segmenting the lumen and the media, respectively. Also, DPU-Net achieves 0.90 JM, 0.25 mm HD and 0.92 JM, 0.30 mm HD over 20 MHz images for segmenting the lumen and the media, respectively. In addition, DPU-Net outperforms existing methods by 8–15% in terms of HD distance. DPU-Net also shows a strong generalization property for predicting images in the test sets that contain a significant amount of major artifacts such as bifurcations, shadows, and side branches that are not common in the training set. Furthermore, DPU-Net runs within 0.03 s to segment each frame with a single modern GPU (Nvidia GTX 1080). The proposed work leverages modern deep learning-based method for segmentation of lumen and the media vessel walls in both 20 MHz and 40 MHz IVUS B-mode images and achieves state-of-the-art results without any manual intervention. The code is available online at https://github.com/Kulbear/IVUS-Ultrasonic .

This study aimed to investigate the relationship between multiple psychosocial and environmental work risk factors and sleep disturbances. This cross-sectional study was conducted among 90 workers in a brick factory in Iran. The health and safety executive (HSE) tool, Epworth Sleepiness Scale (ESS), and Stop-Bang questionnaire were used to determine psychosocial factors, subjective sleepiness, and obstructive sleep apnea (OSA), respectively. Standard objective methods were used to assess the environmental risk factors, including noise, light, heat stress, and respirable particles. Most psychosocial and all environmental work factors were moderately to highly correlated to the ESS score. There were also moderate correlations between the demands (including work load, work patterns, and work environment), role (including a clear understanding of the employees about their role in the organization), and lighting variables and the Stop-Bang score. The results of multivariate logistic regression analysis showed that job control, wet bulb globe temperature (WBGT), and respirable dust were predictive of an ESS score indicating abnormal sleep status and noise was predictive of a Stop-Bang score predictive of OSA. The results suggest that stressors, especially noise, heat stress, and respirable dust, are related to the employees' indices of sleep disturbance independent of other potential workplace confounding factors. These results can highlight the importance of considering multiple psychosocial and environment work risk factors for implementing occupational health and ergonomics interventional programs to prevent sleep disturbances in the workforce.

We present a new mathematical formulation to estimate the intrinsic parameters of a camera in active or robotic platforms. We show that the focal lengths can be estimated using only one point correspondence that relates images taken before and after a degenerate rotation of the camera. The estimated focal lengths are then treated as known parameters to obtain a linear set of equations to calculate the principal point. Assuming that the principal point is close to the image center, the accuracy of the linear equations are increased by integrating the image center into the formulation. We extensively evaluate the formulations on a simulated camera, 3D scenes and real-world images. Our error analysis over simulated and real images indicates that the proposed Simplified Active Calibration method estimates the parameters of a camera with low error rates that can be used as an initial guess for further non-linear refinement procedures. Simplified Active Calibration can be employed in real-time environments for automatic calibrations given the proposed closed-form solutions., 22 pages, 8 figures, and 2 tables. Preprint submitted to Journal of Image and Vision Computing. Journal version of arXiv:1806.03584

Human amniotic membrane (AM) has been widely used for tissue engineering and regenerative medicine applications. AM has many favorable characteristics such as high biocompatibility, antibacterial activity, anti-scarring property, immunomodulatory effects, anti-cancer behavior and contains several growth factors that make it an excellent natural candidate for wound healing. To date, various methods have been developed to prepare, preserve, cross-link and sterilize the AM. These methods remarkably affect the morphological, physico-chemical and biological properties of AM. Optimization of an effective and safe method for preparation and preservation of AM for a specific application is critical. In this review, the isolation, different methods of preparation, preservation, cross-linking and sterilization as well as their effects on properties of AM are well discussed. For each section, at least one effective and safe protocol is described in detail.

We introduce new linear mathematical formulations to calculate the focal length of a camera in an active platform. Through mathematical derivations, we show that the focal lengths in each direction can be estimated using only one point correspondence that relates images taken before and after a degenerate rotation of the camera. The new formulations will be beneficial in robotic and dynamic surveillance environments when the camera needs to be calibrated while it freely moves and zooms. By establishing a correspondence between only two images taken after slightly panning and tilting the camera and a reference image, our proposed Simplified Calibration Method is able to calculate the focal length of the camera. We extensively evaluate the derived formulations on a simulated camera, 3D scenes and real-world images. Our error analysis over simulated and real images indicates that the proposed Simplified Active Calibration formulation estimates the parameters of a camera with low error rates.

Health-related quality of life (HRQOL) has not been investigated among Iranian industrial workers. The present paper aimed to study the influence of the socio-demographic, health and work-related factors on HRQOL among Iranian industrial workers. In this cross-sectional study, participants were 280 workers of two factories. The Persian version of World Health Organization Quality of Life-Brief (WHOQOL-BREF) was used to assess the HRQOL. A questionnaire was developed to assess the socio-demographic, health and work-related factors. Results showed that the means (SD) of physical health, psychological health, social relationships, and environment domains of HRQOL were 13.2 (2.7), 13.3 (2.6), 14.2 (3.5) and 12.6 (2.5), respectively. A multiple linear regression showed that types of job, exercise activity, working schedule, sleep quality, smoking, and conflict between work and social life were significantly associated with physical health domain; whereas, working schedule, marital status, working demand, sleep quality, BMI, and conflict between work and individual life were significantly associated with psychological health domain. Working schedule, working demand, sleep quality, conflict between work and individual life, and having children over two years were significantly associated with social relationship domain; however, working demand, working schedule, smoking, sleep quality, working hour, job satisfaction, marital status and exercise activity were significantly associated with environment domain. Collectively, work-related factors including unhealthy working conditions, unsafe working environments, long working hours, irregular working schedules, and the lack of occupational training may negatively influence the HRQOL of workers. To improve workers’ HRQOL, intervention programs should focus on improving work environment, working schedule, occupational training and restricting working hours.