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A simulation study of the Tunisian Gamma Irradiation Facility for sterile insects release programs has been realized using the GEANT4 Monte Carlo code of CERN. The dose was calculated and measured for high and low dose values inside the irradiation cell. The calculated high dose was in good agreement with measurements. However, a discrepancy between calculated and measured values occurs at dose levels commonly used for sterilization of insects. We argue that this discrepancy is due to the transit dose absorbed during displacement of targets from their initial position towards their irradiation position and displacement of radiation source pencils from storage towards their irradiation position. The discrepancy is corrected by taking into account the transit dose.  相似文献   
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Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease.  相似文献   
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The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters.  相似文献   
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This study aims to evaluate markers of oxidative stress in Tunisian asthmatic patients and investigate whether their markers are correlated with uncontrolled asthma.This prospective cohort study was conducted on 48 healthy subjects and 60 patients with asthma (34 patients with controlled asthma and 26 patients with uncontrolled asthma). The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP), and glutathione (GSH), as well as the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), were estimated in plasma by spectrophotometry.Asthmatic patients have significantly higher plasmatic levels of MDA and AOPP than healthy controls (p < 0.001). Lower GSH level and GPx activity were found in patients with asthma compared to controls (p < 0.001). In contrast, higher SOD activity was noted in asthmatic patients (p < 0.001).The comparison among the patients with controlled asthma and uncontrolled asthma revealed increased MDA and AOPP levels and SOD activity (p < 0.001) as well as a decreased GSH level and GPx activity (p = 0.004, p = 0.019) in patients with uncontrolled asthma. Spirometry level was significantly correlated with SOD activity (r = 0.447; p = 0.010), whereas no significant correlations were found with the other parameters (MDA, AOPP, GSH, and GPx).Asthmatic patients, especially those with uncontrolled asthma, suffer a high degree of reactive oxygen species (ROS) formation causing considerable oxidative stress. Increased MDA level and SOD activity and reduced GPx activity were predictors of poorly controlled asthma.  相似文献   
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IPT-AFM is a proprietary animal component free medium that was developed for rabies virus (strain LP 2061) production in Vero cells. In the present work, we demonstrated the versatility of this medium and its ability to sustain the growth of other cell lines and different virus strains. Here, three models were presented: Vero cells/rabies virus (strain LP 2061), MRC-5 cells/measles virus (strain AIK-C) and BHK-21 cells/rabies virus (strain PV-BHK21). The cell lines were first adapted to grow in IPT-AFM, by progressive reduction of the amount of serum in the culture medium. After their adaptation, BHK-21 cells grew in suspension by forming clumps, whereas MRC-5 cells remained adherent. Then, kinetics of cell growth were studied in agitated cultures for both cell lines. In addition, kinetics of virus replication were investigated.  相似文献   
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We address in the present paper a medical monitoring system designed as a multi-agent based approach. Our system includes mainly numerous agents that act as correlated multi-agent sub-systems at the three layers of the whole monitoring infrastructure, to avoid non informative alarms and send effective alarms at time. The intelligence in the proposed monitoring system is provided by the use of time series technology. In fact, the capability of continuous learning of time series from the physiological variables allows the design of a system that monitors patients in real-time. Such system is a contrast to the classical threshold-based monitoring system actually present in the Intensive Care Units (ICUs) which causes a huge number of irrelevant alarms.  相似文献   
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Abstract  A case report and review of an extraskeletal neuroectodermal tumour of the vagina. Background  Ewing’s sarcoma (ES) and primitive neuroectodermal tumours (PNETs) account for approximately 6–10% of primary malignant bone tumours and, following osteosarcoma, are the second most common group of bone sarcomas in children. Ewing’s sarcoma rarely affects the genitourinary tract. Case summary  We report a rare case of extraskeletal Ewing’s sarcoma diagnosed in a 47-year-old Indian woman presenting with a simple cystic lesion in the posterior wall of the vagina. The histopathology revealed a rare presentation of a primitive malignant extraskeletal neuroectodermal tumour. Conclusion  As our PubMed review found only six previously reported cases of vaginal extraskeletal Ewing’s sarcoma. Presentation as vaginal masses helped in early disease detection.  相似文献   
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