Novel polyimide nanofiltration membranes were prepared by interfacial polymerization using 1,2,4,5-benzene tetracarbonyl chloride (BTC) and trimesoyl chloride solution in
n
-hexane and aqueous ...solution of ethylene diamine on electrospun PVDF support followed by thermal treatment. The BTC was synthesized by the reactions of 1,2,4,5-benzene tetracarboxylic acid with thionyl chloride using triethylamine as a catalyst. The polyimide layer prepared by optimized conditions such as temperature, heating time and interfacial polymerization method found to be good for performance of selective layer. Optimized conditions are confirmed from scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis–differential thermal analysis and differential scanning calorimetry studies. The NF membrane containing polyimide selective layer exhibited 7 ‘gallon/ft
2
day’ water flux and ‘94.8%’ salt rejection. Although the salt rejection values of these polyimide membranes were close to the commercial NF polyamide membranes, these membranes exhibited high chlorine resistance. After chlorination for 100 h in a 200 ppm NaClO solution, polyimide membrane showed 1.4% increased flux and about 2.2% decline in salt rejection.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Post-traumatic stress disorder (PTSD) is associated with increased risk of multiple medical problems including myocardial infarction. However, a direct link between PTSD and atherosclerotic coronary ...artery disease (CAD) has not been made. Coronary artery calcium (CAC) score is an excellent method to detect atherosclerosis. This study investigated the association of PTSD to atherosclerotic CAD and mortality. Six hundred thirty-seven veterans without known CAD (61 ± 9 years of age, 12.2% women) underwent CAC scanning for clinical indications and their psychological health status (PTSD vs non-PTSD) was evaluated. In subjects with PTSD, CAC was more prevalent than in the non-PTSD cohort (76.1% vs 59%, p = 0.001) and their CAC scores were significantly higher in each Framingham risk score category compared to the non-PTSD group. Multivariable generalized linear regression analysis identified PTSD as an independent predictor of presence and extent of atherosclerotic CAD (p <0.01). During a mean follow-up of 42 months, the death rate was higher in the PTSD compared to the non-PTSD group (15, 17.1%, vs 57, 10.4%, p = 0.003). Multivariable survival regression analyses revealed a significant linkage between PTSD and mortality and between CAC and mortality. After adjustment for risk factors, relative risk (RR) of death was 1.48 (95% confidence interval CI 1.03 to 2.91, p = 0.01) in subjects with PTSD and CAC score >0 compared to subjects without PTSD and CAC score equal to 0. With a CAC score equal to 0, risk of death was not different between subjects with and without PTSD (RR 1.04, 95% CI 0.67 to 6.82, p = 0.4). Risk of death in each CAC category was higher in subjects with PTSD compared to matched subjects without PTSD (RRs 1.23 for CAC scores 1 to 100, 1.51 for CAC scores 101 to 400, and 1.81 for CAC scores ≥400, p <0.05 for all comparisons). In conclusion, PTSD is associated with presence and severity of coronary atherosclerosis and predicts mortality independent of age, gender, and conventional risk factors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Intravascular papillary endothelial hyperplasia (IPEH) is an uncommon benign vascular disease characterized by endothelial cell proliferation and papillary formation within the lumen of blood vessels ...arising from an organizing thrombus. The occurrence of this uncommon lesion is about 2% of all vascular tumors. IPEH mostly occurs in the 5th decade of life, and there is no gender or age predilection. Nevertheless, some studies have suggested that IPEH is more common in women than in men. The clinical features are mostly asymptomatic, and the lesion is typically characterized as a small, firm, slightly elevated mass with red to blue discoloration of the overlying skin. The main diagnosis of the lesion is based on histological examination. The most common locations of IPEH are head and neck, fingers, and trunk. The occurrence of IPEH in the urethra is extremely rare, with only a few cases having been reported in the literature. We describe a 70-year-old woman with a complaint of dysuria and urethral bleeding of 3 days' duration. Clinically, the lesion was a palpable firm mass in the urethra. Urethrocystoscopy illustrated a dark mass, a few millimeters in size, with bleeding. Histologic findings revealed dilated blood vessels with multiple papillary projections into the lumen. Thus, based on these findings, a final diagnosis of Masson's tumor was confirmed. According to clinical and radiographic findings, this lesion is similar to malignant lesions and its accurate diagnosis is based on microscopic findings. Therefore, awareness of the microscopic characteristics of this tumor is very important for clinicians to rule out the presence of malignant vascular lesions and to avoid unnecessarily aggressive therapy.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract Objectives To determine the epidemiological characteristics of fatal traffic accidents in Fars province, Iran. Study design This cross-sectional study included 3642 traffic accident deaths ...in Fars province, Iran between November 2009 and November 2011. The data source was the Fars Forensic Medicine Registry, which covers the entire province. According to Iranian law, all deaths resulting from injuries or accidents must be investigated to determine the exact cause of death by autopsy. All such deaths are referred to forensic medicine centres in each city, and all data are sent to the main centre in Shiraz, the capital city of Fars province. Results Males accounted for 78.3% of the decedents (sex ratio of almost 3.6:1), and the mean ± standard deviation age of all decedents was 32.2 ± 20.3 years. Autopsy reports indicated that head trauma was the most common cause of death. Most collisions were vehicle–vehicle crashes (52.3%), with cars and motorcycles being the most prevalent modes of transport (39.6% and 24.6%, respectively). Fatal accidents were most common during the summer. Most fatal injuries (61.4%) occurred on outer-city roads and 27.4% occurred on inner-city roads. Significant associations were found between decedent's status (car driver, motorcycle driver or passenger, pedestrian or passenger) and interval between injury and death, light conditions at the scene of the accident, place of death, site of injury and cause of death. Conclusion Although the clinical management of trauma patients has improved in Iran, coordination between trauma system organizations is required to decrease the burden of injuries.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Introduction
Hematopoietic stem cell transplantation (HSCT) is widely used in the treatment of malignant and non-malignant diseases. Due to advances in the number of survivors of this treatment, the ...number of survivors is increasing, but the late complications of this therapeutic approach such as secondary cancers have been long term and have not been fully controlled.
Methods
The present meta-analysis study was performed by considering English-language articles in the databases including Web of Science, Scopus and PubMed. This meta-analysis included cohort studies that reported an incidence of cancer following stem cell transplantation (SCT). Random/fixed effect size meta-analyses were used to standardize the incidence ratio for different cancers.
Results
22 studies that evaluated patients receiving SCT (
n
= 270,063) were included in the study. The study found 9233 cases of cancer after transplantation. Meta-analysis showed that the risk of cancer after SCT was SIR = 1.66 (95% CI 1.47–1.86). The most common cancers observed in SCT recipients were bone tissue, head and neck cancers, and melanoma, with SIRs of 10.04 (3.48–16.61), 6.35 (4.76–7.93) and 3.52 (2.65–4.39), respectively.
Conclusion
The meta-analysis findings showed that the risk of secondary cancers after HSCT was significantly increased in most types of cancers. Consequently, diagnostic tests for common cancers should be included in the screening program of these patients for the prevention and early detection of high-risk cancers.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
Transcutaneous electrical nerve stimulation (TENS) can reduce acute and chronic pain. Unilateral fatigue can produce discomfort in the affected limb and force and activation deficits in ...contralateral non-exercised muscles. TENS-induced local pain analgesia effects on non-local fatigue performance are unknown. Hence, the aim of the study was to determine if TENS-induced pain suppression would augment force output during a fatiguing protocol in the treated and contralateral muscles.
Methods
Three experiments were integrated for this article. Following pre-tests, each experiment involved 20 min of TENS, sham, or a control condition on the dominant quadriceps. Then either the TENS-treated quadriceps (TENS_Treated) or the contralateral quadriceps (TENS_Contra) was tested. In a third experiment, the TENS and sham conditions involved two\; 100-s isometric maximal voluntary contractions (MVC) (30-s recovery) followed by testing of the contralateral quadriceps (TENS_Contra-Fatigue). Testing involved single knee extensors (KE) MVCs (pre- and post-test) and a post-test 30% MVC to task failure.
Results
The TENS-treated study induced greater (
p
= 0.03; 11.0%) time to KE (treated leg) failure versus control. The TENS_Contra-Fatigue induced significant (
p
= 0.04; 11.7%) and near-significant (
p
= 0.1; 7.1%) greater time to contralateral KE failure versus sham and control, respectively. There was a 14.5% (
p
= 0.02) higher fatigue index with the TENS (36.2 ± 10.1%) versus sham (31.6 ± 10.6%) conditions in the second fatigue intervention set (treated leg). There was no significant post-fatigue KE fatigue interaction with the TENS_Contra.
Conclusions
Unilateral TENS application to the dominant KE prolonged time to failure in the treated and contralateral KE suggesting a global pain modulatory response.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
One of the limiting factors of electron beam lifetime in low emittance storage rings is Head-Tail (HT) instability. Low emittance storage rings typically have a large negative natural chromaticity ...due to the strong quadrupoles. Above transition large negative natural chromaticity leads to large Head-Tail instability which limit the beam lifetime. Since the threshold current of HT instability is directly related to linear chromaticity, increasing the linear chromaticity to slightly positive value is a solution to prevent HT instability. In this paper we in-creased the chromaticity of Iranian Light Source Facility (ILSF) to (+4, +4) and we will investigate the beam dynamics of ILSF 3GeV storage ring in high chromaticity. For reaching this aim we have used two families of sextupoles for chromaticity correction and then optimized them to maximize the dynamic aperture and Touschek lifetime. The beam dynamics of high chromaticity lattice is presented in this paper.
Abstract Respiratory drug delivery has been under the research spotlight for the past few decades, mainly due to the high incidence of pulmonary diseases and the fact that this type of delivery ...offers the highest efficiency for treatment. Despite its invaluable benefits, there are some major drawbacks to respiratory drug delivery, the most important of which being poor delivery efficiency and relatively high drug deposition in undesirable regions, such as the mouth cavity. One way to improve the efficiency of respiratory drug delivery with metered-dose inhalers is placing a respiratory spacer between the inhaler exit and the mouth. It is argued that high drug deposition in the immediate airways of the respiratory system is strongly affected by relatively high initial momentum of pharmaceutical particles leaving the inhaler. A respiratory spacer, however, can provide an expansion region in which the initial momentum of particles can subside. As a result, particles enter the patient׳s oral cavity more gradually and are more likely to reach the desired regions. In this study, the effectiveness of using three commercial spacers paired with a commercial inhaler is examined through numerical investigation of fluid flow and particle transport phenomena. Particles ranging from 1 to 50 µm in diameter are tracked using a Lagrangian point of view and fluid flow fields are resolved using the LRN k-ω turbulence model. A novel particle injection method is introduced and is demonstrated to be able to adequately capture the effects of particle initial momentum. Lastly, a few design suggestions are made.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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