86 research outputs found
Conductance fluctuations and distribution at metal-insulator transition induced by electric field in disordered chain
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A mobile assisted coverage hole patching scheme based on particle swarm optimization for WSNs
Wireless sensor networks (WSNs) have drawn much research attention in recent years due to the superior performance in multiple applications, such as military and industrial monitoring, smart home, disaster restoration etc. In such applications, massive sensor nodes are randomly deployed and they remain static after the deployment, to fully cover the target sensing area. This will usually cause coverage redundancy or coverage hole problem. In order to effectively deploy sensors to cover whole area, we present a novel node deployment algorithm based on mobile sensors. First, sensor nodes are randomly deployed in target area, and they remain static or switch to the sleep mode after deployment. Second, we partition the network into grids and calculate the coverage rate of each grid. We select grids with lower coverage rate as candidate grids. Finally, we awake mobile sensors from sleep mode to fix coverage hole, particle swarm optimization (PSO) algorithm is used to calculate moving position of mobile sensors. Simulation results show that our algorithm can effectively improve the coverage rate of WSNs
Iterative Reconstructions in Reduced-Dose CT: Which Type Ensures Diagnostic Image Quality in Young Oncology Patients?
To compare adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) algorithms for reduced-dose computed tomography (CT).
Forty-four young oncology patients (mean age 30â±â9 years) were included. After routine thoraco-abdominal CT (dose 100%, average CTDI javax.xml.bind.JAXBElement@e7f585f 9.1â±â2.4âmGy, range 4.4-16.9âmGy), follow-up CT was acquired at 50% (average CTDI javax.xml.bind.JAXBElement@2e35610f 4.5â±â1.2âmGy, range 2.2-8.4âmGy) in 29 patients additionally at 20% dose (average CTDI javax.xml.bind.JAXBElement@37ad3473 1.9â±â0.5âmGy, range 0.9-3.4âmGy). Each reduced-dose CT was reconstructed using both ASIR and MBIR. Four radiologists (two juniors and two seniors) blinded to dose and technique read each set of CT images regarding objective and subjective image qualities (high- or low-contrast structures), subjective noise or pixilated appearance, diagnostic confidence, and lesion detection.
At all dose levels, objective image noise was significantly lower with MBIR than with ASIR (Pâ<â0.001). The subjective image quality for low-contrast structures was significantly higher with MBIR than with ASIR (Pâ<â0.001). Reduced-dose abdominal CT images of patients with higher body mass index (BMI) were read with significantly higher diagnostic confidence than images of slimmer patients (Pâ<â0.001) and had higher subjective image quality, regardless of technique. Although MBIR images appeared significantly more pixilated than ASIR images, they were read with higher diagnostic confidence, especially by juniors (Pâ<â0.001).
Reduced-dose CT during the follow-up of young oncology patients should be reconstructed with MBIR to ensure diagnostic quality. Elevated body mass index does not hamper the quality of reduced-dose CT
DERMATOPOLYMYOSITES PARANEOPLASIQUES. A PROPOS DE 06 CAS
Introduction: Adult dermatopolymyositis is associated with cancer in 15 to 50% of cases. The aim of our study was to search for predictive factors of cancer among adults with dermatomyositis. Methods: We made a retrospective survey of 1981 to 2005 to the department of Dermatology Ibn Sina of Rabat. We collected 44 cases of DM. The parameters assessed were: age, gender, cutaneous extension lesion, cutaneous necrosis, muscular weakness, articular reach, muscular enzymes, intensity of the inflammatory syndrome, electromyographic abnormalitis and the improvement or not with the corticothĂ©rapie. Results: cancers were diagnosed in six cases. Mean age was of 65 years and sex-ratio (F/H) was 2.the beginning was brutal with muscular weakness in 1/3 of cases, none of our patients didn't have a skin necrosis. The 2 / 3 of our patients had normal muscular enzymes. The VS was accelerated for 04 of our patients. Our patients didn't improve whith the corticothĂ©rapie. Conclusion: In our limited set, the advanced age, muscular weakness, articular reach, inflammatory syndrome, electromyographic abnormalities, the no improvement with the corticothĂ©rapie seemed to be prĂ©dictive.Introduction : Les dermatopolymyosites de lâadulte sont associĂ©es Ă une nĂ©oplasie dans 15 Ă 50% des cas. Lâobjectif de notre Ă©tude Ă©tait de rechercher les signes cliniques et paracliniques prĂ©dictifs  de lâassociation DM et nĂ©oplasie. MatĂ©riel et mĂ©thodes: Nous avons rĂ©alisĂ© une Ă©tude rĂ©trospective de 1981 Ă 2005 au service de dermatologie du CHU Ibn Sina de Rabat. Nous avons collectĂ© 44 cas de DM. Les critĂšres Ă©valuĂ©s Ă©taient : lâĂąge, le sexe, lâextension des lĂ©sions cutanĂ©es, la nĂ©crose cutanĂ©e, lâintensitĂ© de lâatteinte musculaire, lâatteinte articulaire, les enzymes musculaires, lâintensitĂ© du syndrome inflammatoire,  anomalies elĂ©ctromyographiques et lâabsence ou la rĂ©ponse Ă la corticothĂ©rapie. RĂ©sultats : Six  malades sur 44 Ă©tudiĂ©s avait une nĂ©oplasie associĂ©e, soit 14,28% .LâĂąge moyen Ă©tait de 65 ans, Le sexe ratio H/F Ă©tait de deux .Le mode de dĂ©but Ă©tait brutal avec une atteinte musculaire intense dans un tiers des cas, aucun de nos malades nâavait une nĂ©crose cutanĂ©e. Les deux tiers de nos patients avaient un taux dâenzymes musculaires normal. La vitesse de sĂ©dimentation (VS) Ă©tait accĂ©lĂ©rĂ©e pour quatre de nos malades. Nos malades nâont pas rĂ©pondu Ă la corticothĂ©rapie. Conclusion : Dans notre sĂ©rie limitĂ©e, lâĂąge avancĂ©, lâintensitĂ© de lâatteinte musculaire, lâatteinte articulaire, le syndrome inflammatoire, les anomalies Ă©lectromyographiques, et la non rĂ©ponse Ă la corticothĂ©rapie semblaient ĂȘtre prĂ©dictifs
Results from evaluations of models and cost-effectiveness tools to support introduction decisions for new vaccines need critical appraisal
The World Health Organization (WHO) recommends that the cost-effectiveness (CE) of introducing new vaccines be considered before such a programme is implemented. However, in low- and middle-income countries (LMICs), it is often challenging to perform and interpret the results of model-based economic appraisals of vaccines that benefit from locally relevant data. As a result, WHO embarked on a series of consultations to assess economic analytical tools to support vaccine introduction decisions for pneumococcal, rotavirus and human papillomavirus vaccines. The objectives of these assessments are to provide decision makers with a menu of existing CE tools for vaccines and their characteristics rather than to endorse the use of a single tool. The outcome will provide policy makers in LMICs with information about the feasibility of applying these models to inform their own decision making. We argue that if models and CE analyses are used to inform decisions, they ought to be critically appraised beforehand, including a transparent evaluation of their structure, assumptions and data sources (in isolation or in comparison to similar tools), so that decision makers can use them while being fully aware of their robustness and limitations
Adoption of new health products in low and middle income settings: how product development partnerships can support country decision making
When a new health product becomes available, countries have a choice to adopt the product into their national health systems or to pursue an alternate strategy to address the public health problem. Here, we describe the role for product development partnerships (PDPs) in supporting this decision-making process. PDPs are focused on developing new products to respond to health problems prevalent in low and middle income settings. The impact of these products within public sector health systems can only be realized after a country policy process. PDPs may be the organizations most familiar with the evidence which assists decision making, and this generally translates into involvement in international policy development, but PDPs have limited reach into endemic countries. In a few individual countries, there may be more extensive involvement in tracking adoption activities and generating local evidence. This local PDP involvement begins with geographical prioritization based on disease burden, relationships established during clinical trials, PDP in-country resources, and other factors. Strategies adopted by PDPs to establish a presence in endemic countries vary from the opening of country offices to engagement of part-time consultants or with long-term or ad hoc committees. Once a PDP commits to support country decision making, the approaches vary, but include country consultations, regional meetings, formation of regional, product-specific committees, support of in-country advocates, development of decision-making frameworks, provision of technical assistance to aid therapeutic or diagnostic guideline revision, and conduct of stakeholder and Phase 4 studies. To reach large numbers of countries, the formation of partnerships, particularly with WHO, are essential. At this early stage, impact data are limited. But available evidence suggests PDPs can and do play an important catalytic role in their support of country decision making in a number of target countries
Increased risk of contralateral breast cancers among overweight and obese women: a time-dependent association
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