Measurement and Characterization of the Stationary Noise in Narrowband Power Line Communication

Understanding the interference scenario in power lines network is a key step to characterize the power line communication (PLC) system. This paper focuses on the characterization and modelling of the stationary noise in Narrowband PLC. Measurement and analysis of noise is carried out in the Tunisian outdoor Low Voltage (LV) power line network in the frequency band below 500 kHz. Based on existing models and measurements results, a parametric model of noise is proposed; the model parameters are statistically studied.Comment: 11th International Conference on Networks & Communications (NeTCoM 2019

Caplan’s syndrome in an elderly-onset rheumatoid arthritis patient: About a new case

Introduction: The association of silicosis and RA is rare compared to pulmonary manifestations of rheumatoid arthritis (RA). A history of lung disease or a long exposure at work to silica and typical radiographic lesions on chest X-ray suggest the diagnosis of Caplan’s syndrome. We describe the case of an elderly Tunisian male RA patient with the Caplan’s syndrome diagnosed after prolonged exposure to silica. Case report: A 62-year old patient was referred for exploration of a chronic symmetrical polyarthritis for 2 years involving the hands, elbows, forefeet, and knees and accompanied by prolonged morning stiffness. He had no history of lung disease but had worked in a ceramic plant for 20 years. He presented with arthritis of the wrists and knees with a rheumatoid nodule of the left elbow. Joint destruction was present in both hands and feet. Rheumatoid factor and anti-cyclic citrullinated peptide antibodies were highly positive (135 UI/L and 363 UI/L respectively). The patient was diagnosed as RA and the disease activity score (DAS-28) was up for 6.87. His breathing was normal, pulmonary auscultation and spirometry were normal. Chest X-rays revealed a multiple micro-nodules distributed throughout the lungs but predominantly in the upper and middle zones. Bronchoalveolar lavage showed a pauci-cellular liquid and chest CT scan showed bilateral, round, well-delimited small centri-lobular nodules which predominate the upper lobes. There was infra-centimetrical adenopathy with mediastinal calcification. Conclusion: Prolonged exposure to silica dust has a remarkable influence on the development of RA with a suggested intricacy in to its pathogenesis

Risk factors associated with bone loss and occurrence of fragility fractures in rheumatoid arthritis patients

Aim of the work: To investigate the bone mineral density (BMD) in rheumatoid arthritis (RA) Tunisian patients, to identify the risk factors associated with its decrease and to assess the fracture risk. Patients and methods: The study included 173 patients and 173 matched healthy controls. BMD was assessed by the dual-energy X-ray absorptiometry. The risk of hip fracture (HF) and major osteoporotic fracture (MOF) were assessed using the fracture risk assessment tool (FRAX). The disease activity, radiological severity and functional status were investigated. Results: The mean age of patients was 54.1 ± 11.04 years and 141 were females; 71.6% menopausal. Disease duration was 8.2 ± 8 years and disease activity score was 5.54 ± 1.26. Sharp van-der-Heijde (SvdH) score was 113.9 ± 106.8, health assessment questionairre (HAQ) score 1.03 ± 0.9. The BMD was significantly reduced in 138 (79.8%) patients and FRAX was higher compared to control (p < .001). The frequency of osteoporosis (48% vs. 18.5%), the risk of MOF (1.8 ± 2.6 vs. 0.6 ± 0.3) and HF (0.7 ± 1.7 vs. 0.08 ± 0.1) were significantly higher in RA patients than in controls. Bone loss in RA was significantly associated with age, low body mass index (BMI), longer disease duration, rheumatoid factor, SvdH, atlantoaxial subluxation and corticosteroids use. Menopause, low calcium intake, erythrocyte sedimentation rate and HAQ were risk factors for reduced BMD. The risk of MOF and HF was associated with age, menopause, calcium intake, BMI, disease duration, HAQ, SvdH, cumulative dose and duration of corticosteroids. Conclusion: bone loss and fragility fracture are frequent in RA and related to disease severity, function impairment and corticosteroids use. Keywords: Rheumatoid arthritis, Osteoporosis, Fracture, FRAX, Bone mineral densit