Evolution to 200G Passive Optical Network

New generation passive optical network aims at providing more than 100 Gb/s capacity. Thanks to recent progress enabling a variety of optical transceivers up to 40 Gb/s, many evolution possibilities to 200G PONs (passive optical network) could be investigated. This work proposes two directly deployable cases of evolution to 200G PON based on the combination of these improved optical transceivers and WDM (wavelength division multiplexing). The physical layer of the optical network has been simulated with OptiSystem software to show the communication links performances behavior when considering key components parameters in order to achieve good network design for a given area. The complexity of the proposed architectures and financial cost comparisons are also discussed.Comment: http://www.davidpublishing.com/davidpublishing/Upfile/2/7/2013/2013020707494407.pd

Manufacturing Brick from Attapulgite Clay at Low Temperature by Geopolymerization

International audienceGround to approximately 250-mesh size powder, attapulgite mining waste was mixed with different alkali concentrations (4, 8 and 12M NaOH) to form thick paste and statically compacted (~10 MPa). The samples were cured at 40 °C and 60 % RH for long-term storage (1 week-3 months) and at 120 °C and 0 % RH for short-term storage of varying periods of time (6, 12 and 24 h). This particular clay was characterized using a variety of techniques including physical (DTA, X-ray, laser granulometry, microstructure, PSD, etc.) and chemical analysis. The main minerals present are palygorskite, quartz, calcite and hematite. DTA/TGA curves resemble those obtained when a sample of kaolin is first heated and then cooled. When treated with 12 M-alkali solutions and cured for 7 days at 80 °C, the minerals present are montmorillonite, larnite, stilbite, dolomite and calcite. Palygorskite clay disappeared after the reaction. In long-term tests, strength did not increase with time for attapulgite clays activated with sodium hydroxide. For all concentrations and periods, the strength obtained with 8 M concentration was greater. In short-term tests, the maximum strength was obtained after 24 h for 12M concentrations. After 12 h of curing, alkali activation of attapulgite at 120 °C appears to be much more advantageous in terms of strength. The fiber structure of the attapulgite disappeared and was completely changed into one resembling plates. The low conductivity obtained suggests that the Na component of the 8 and 12 M brick reacts nearly completely

Effects of Hot-Water Treatment of Black Spruce and Trembling Aspen Bark RAW Material on the Physical and Mechanical Properties of Bark Particleboard

The understanding of the interaction between bark extractives and adhesives is fundamental in the manufacture of bark particleboard for optimum adhesive curing, and mechanical and physical properties of the boards. The effect of hot-water treatment on black spruce and trembling aspen bark was investigated to highlight its impact on the bark particles/phenol-formaldehyde adhesive system, and on the physical and mechanical properties of bark particleboard made from hot-water-treated bark of both species. Bark was soaked in hot water maintained at 100°C for 3 h. The results showed that the hot-water treatment affects the physical and chemical properties of the bark by decreasing hydrophilic characteristics, acidity, and the amount of condensable polyphenols that can react with formaldehyde. The mechanical properties, including static bending and internal bond of particleboard made from untreated black spruce and trembling aspen bark, were higher than those of boards made from hot-water-treated bark of the same species. The thickness swelling of particleboard made from hot-water-treated black spruce and trembling aspen bark was higher than that made from untreated bark. One exception occurred for particleboard made from 100% trembling aspen bark for which no significant difference was found between particleboards made from treated and untreated barks

Evaluation des complications cardiaques chez les hémodialysés chroniques de Dakar

Introduction: L'évaluation cardiovasculaire est essentielle en hémodialyse périodique car les affections cardiovasculaires sont la première cause de mortalité chez les hémodialysés chroniques. Nous avons conduit cette étude afin de déterminer la prévalence et le type des différentes complications cardiovasculaires et d'identifier les principaux facteurs de risque cardiovasculaire. Méthodes: Il s'agissait d'une étude rétrospective de 4 ans portant sur les dossiers de patients traités au moins 6 mois en hémodialyse et ayant des explorations cardio-vasculaires comportant une radiographie du thorax de face, un électrocardiogramme et une échographie cardiaque. Les données épidémiologiques, cliniques, paracliniques, les aspects évolutifs des complications cardiaques ont été recueillies pour chaque patient retenu. Résultats: Trente huit dossiers de patients ont été inclus dans cette étude. L'âge moyen était de 52 ans ± 12,85 et le sex-ratio H/F de 1,53. Les complications cardiovasculaires étaient dominées par l'hypertrophie ventriculaire gauche (71,05 %), la maladie coronaire (34,21%), l'insuffisance cardiaque congestive (18,42%), Calcifications vasculaires (5,78 %), les troubles du rythme (7.89%), les fuites valvulaires mitrales (44,73%), tricuspidiennes (42,10%) et les accidents vasculaires cérébraux hémorragiques (5,26%). L'incidence moyenne de l'HVG était de 81% chez les patients hypertendus. Au cours de cette étude, 27 patients avaient poursuivi l'hémodialyse et 11 étaient décédés dont 6 de causes cardiovasculaires (54,55%). Conclusion: L'hémodialyse est une technique d'épuration qui expose les patients à de multiples complications cardiovasculaires.Pan African Medical Journal 2016; 23: 4

Meeting the challenges of information disorder in the Global South

The research was conducted collaboratively, with regional reports provided by local teams from Research ICT Africa, InternetLab (Latin America and the Caribbean), LIRNEasia (Asia), and Arab Reporters for Investigative Journalism (Middle East and North Africa). This detailed study provides an overview of the entities that are active in the fight against information disorder in the MENA region, and the methods and responses they use. It also discusses and analyzes legal and human rights issues and the context of freedom of opinion and expression in which they operate

Scleroderma renal crisis in tropical region: two senegalese cases

Scleroderma renal crisis (SRC) is defined as the new onset of accelerated arterial hypertension and /or rapidly progressive oliguric renal failure during the course of systemic sclerosis. It is a rare but life-threatening complication. This formerly serious complication has got a considerable brighter outlook since the introduction of angiotensin converting enzyme inhibitors (ACE) however the mortality is still remaining high. We report two cases of SRC which to our knowledge are the firsts described in Dakar. They were two women aged 45 and 32 years, one of them was previously following for systemic sclerosis. Both of them had malignant hypertension associated with rapidly progressive renal failure, the other was put under corticosteroid therapy four months before SRC occurrence. The histological and laboratory finding showed thrombotic microangiopathy. The height blood pressure returned to normal value after treatment with ACE inhibitors. The final outcome was undesirable with the death of one after two months due to the hemodialysis discontinuation and persistence of renal failure in the other.Keywords: Scleroderma renal crisis, corticosteroids, thrombotic microangiopathy, Daka

Une lesion cutanée persistante non cicatricielle depuis 3 ans: le pyoderma gangrenosum

Le pyoderma gangrenosum (PG) est une dermatose neutrophilique non infectieuse rare souvent méconnue. Il se présente généralement par des ulcérations cutanées inflammatoires, très douloureuses et d'évolution rapide. Il est fréquemment retrouvé dans un contexte de néoplasie, de pathologies inflammatoires digestives, rhumatologiques et/ou hématologiques. Son diagnostic est très souvent tardif après de multiples échecs thérapeutiques. Nous rapportons un cas de pyoderma gangrenosum dont le diagnostic n'a pas été criant. Un patient a été admis dans notre service pour une lésion dermatologique persistante et d'évolution défavorable malgré les débridements et l'administration d'antibiotiques. Il était suivi pour un cancer de la prostate, une hypertension artérielle et un asthme. Du fait des anomalies biologiques observées telles qu'une hyperleucocytose à polynucléaires neutrophiles avec myélémie à myélocytes et métamyélocytes, sans blastose sanguine et une anémie normochrome normocytaire, une leucémie myéloïde chronique a été évoquée chez ce patient. Elle a par la suite été infirmée devant les différents examens complémentaires non concluants. C'est ainsi que le diagnostic de PG a été évoqué et confirmé à l'examen anatomopathologique montrant un aspect histopathologique d'un tissu de granulation concordant avec un pyoderma gangrenosum et une absence de signe histologique de malignité. L'institution d'un traitement à base de corticothérapie a abouti à la guérison

Décentralisation De La Dialyse Au Sénégal : Expérience D’1 An Du Centre De Tambacounda A l’Est Du Pays

Hemodialysis has made numerous and significant progress in recent decades resulting in life expectancy increase (thirty or forty years). The aim of our study was to assess the treatment of acute and chronic hemodialysis in the reference center of Tambacounda. Patients and methods: This was a prospective study over a one-year period (April 2013 to March 2014) in the hemodialysis center of the regional hospital of Tambacounda, 450km away from Dakar. The study focused on epidemiological, clinical, paraclinical and scalable data. Results: Fifty-nine patients were involved in the study. The sex ratio was 0.85 (32F/ 27M). The mean age was 41.3 years [12-72 years old]. Nineteen patients were on dialysis treatment for acute renal failure (ARF) (32.2%) and 40 were chronic hemodialysis patients (67.79%). Fifty patients were under emergency dialysis (84.7%) including 17 in intensive care (28.8%). Most chronic hemodialysis patients had 3 sessions per week (98.3%). Only 9 patients were monitored in nephrology prior to dialysis (22%). Thirty-two patients had a femoral double-lumen catheter (54.23%), 6 patients used ordinary double- lumen jugular catheters (10.17%) and 3 received tunneled jugular catheters (5.09%). Eighteen patients had functional arteriovenous (AV) fistula (18.51%). The mean hemoglobin was 7 g/dl. Only 11 patients had erythropoietin-based therapy. In acute renal impairment there were 8 deaths (42.10%), whereas in chronic renal failure the fatality rate was 18.8% (n = 9). Conclusion: Our study has demonstrated the benefits of decentralizing dialysis treatment in the provinces. However there is a need to implement the accompanying measures, such as the availability of some essential medicines for all hemodialysis patients, and equipment of intensive care units

HER2-Specific Chimeric Antigen Receptor–Modified Virus-Specific T Cells for Progressive Glioblastoma: A Phase 1 Dose-Escalation Trial

Glioblastoma is an incurable tumor, and the therapeutic options for patients are limited. To determine whether the systemic administration of HER2-specific chimeric antigen receptor (CAR)-modified virus-specific T cells (VSTs) is safe and whether these cells have antiglioblastoma activity. In this open-label phase 1 dose-escalation study conducted at Baylor College of Medicine, Houston Methodist Hospital, and Texas Children's Hospital, patients with progressive HER2-positive glioblastoma were enrolled between July 25, 2011, and April 21, 2014. The duration of follow-up was 10 weeks to 29 months (median, 8 months). Monotherapy with autologous VSTs specific for cytomegalovirus, Epstein-Barr virus, or adenovirus and genetically modified to express HER2-CARs with a CD28.ζ-signaling endodomain (HER2-CAR VSTs). Primary end points were feasibility and safety. The key secondary end points were T-cell persistence and their antiglioblastoma activity. A total of 17 patients (8 females and 9 males; 10 patients ≥18 years [median age, 60 years; range, 30-69 years] and 7 patients <18 years [median age, 14 years; range, 10-17 years]) with progressive HER2-positive glioblastoma received 1 or more infusions of autologous HER2-CAR VSTs (1 × 106/m2 to 1 × 108/m2) without prior lymphodepletion. Infusions were well tolerated, with no dose-limiting toxic effects. HER2-CAR VSTs were detected in the peripheral blood for up to 12 months after the infusion by quantitative real-time polymerase chain reaction. Of 16 evaluable patients (9 adults and 7 children), 1 had a partial response for more than 9 months, 7 had stable disease for 8 weeks to 29 months, and 8 progressed after T-cell infusion. Three patients with stable disease are alive without any evidence of progression during 24 to 29 months of follow-up. For the entire study cohort, median overall survival was 11.1 months (95% CI, 4.1-27.2 months) from the first T-cell infusion and 24.5 months (95% CI, 17.2-34.6 months) from diagnosis. Infusion of autologous HER2-CAR VSTs is safe and can be associated with clinical benefit for patients with progressive glioblastoma. Further evaluation of HER2-CAR VSTs in a phase 2b study is warranted as a single agent or in combination with other immunomodulatory approaches for glioblastoma