411 research outputs found

    Cloud Computing Solution for Monitoring Arid Rangeland Dynamics: Case of Moroccan Highlands and Southern Acacia Ecosystems

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    The wide availability of free satellite imagery, the recent development of cloud platforms dedicated to big spatial data (Big Data) that integrates both image archives from different providers, processing algorithms, distributed processing capabilities as well as an application programming interface (API) that facilitate scripting and automation process opened new perspectives for the use of vegetation observation time series over long timestamps and over large spatial scales (almost planetary). This work aims at harnessing these technologies and building up an automated solution to monitor rangeland rehabilitation dynamics in arid lands and to assess the effectiveness of stakeholder’s management strategies. Such solution is based on graphical user interface that facilitate the process and on the use of analysis functions relaying on analysing temporal trajectories (time series) of different spectral indices derived from satellite images (Landsat or Sentinel) at the required spatial analysis scale. The solution is implemented using java script as scripting language using the functions offered by GEE API. The graphical user interface of the first prototype is exploitable by the means of a standard web browser and it is accessible even to people without any background in regard to programming languages or to remote sensing skills. The process was tested for two arid sites on Morocco: acacia ecosystems on the southern part of Morocco and the highlands on Moroccan eastern parts mainly on sites recently rehabilitated. It has been qualified is promising solution

    LEÏOMYOSARCOME UTERIN DE PRESENTATION INHABITUELLE

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    Utérin Leiomyosarcoma is rare [1.5]. It is likely conjunctiva and developed at the expense of mesenchymal elements of the myometrium. The uterus bicornis united cervical represents 39% of all uterine malformations [8]. The prevalence of these abnormalities is estimated at 0.5%. The association leïomyosarcoma and uterine malformation still very exceptional. The purpose of our work is to study the unique combination from the clinical, paraclinical, pathological, and evolving therapeutic.Le léiomyosarcome utérin est une tumeur maligne, rare [1,5].Elle est de nature conjonctive et développée aux dépens des éléments mésenchymateux du myomètre. L’utérus bicorne uni cervical représente 39% de l’ensemble des malformations utérines [8]. La prévalence de ces malformations est estimée à 0,5%. L’association leïomyosarcome utérin et malformation utérine reste très exceptionnelle et ce du fait que la malformation utérine est de diagnostic précoce à un âge jeune contrairement au leiomyosarcome utérin qui survient chez des femmes d’âge avancé. Le but de notre travail est d’étudier à partir de notre observation cette association exceptionnelle sur le plan clinique, paraclinique, anatomopathologique, thérapeutique et évolutif

    LANDSLIDE SUSCEPTIBILITY MAPPING IN THE MUNICIPALITY OF OUDKA, NORTHERN MOROCCO: A COMPARISON BETWEEN LOGISTIC REGRESSION AND ARTIFICIAL NEURAL NETWORKS MODELS

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    The Rif is among the areas of Morocco most susceptible to landslides, because of the existence of relatively young reliefs marked by a very important dynamics compared to other regions. These landslides are one of the most serious problems on many levels: social, economic and environmental. The increase in the frequency and impact of landslides over the past decade has demonstrated the need for an in-depth study of these phenomena, allowing the identification of areas susceptible to landslides. The main objective of this study is to identify the optimal method for the mapping of the area susceptible to landslides in municipality of Oudka. This area has been marked by the largest landslide in the region, caused by heavy rainfall in 2013. Two Statistical Methods i) Regression Logistics (LR) ii) Artificial Neural Networks (ANN), were used to create a landslide susceptibility map. The realization of this susceptibility map required, first, the mapping of old landslides by the aerial photography, the data of the geological map and by the data obtained using field surveys using GPS. A total of 105 landslides were mapped from these various sources. 50% of this database was used for model building and 50% for validation. Eight independent landslide factors are exploited to detect the most sensitive areas: altitude, slope, aspect, distance of faults, distance streams, distance from roads, lithology and vegetation index (NDVI). The results of the landslide susceptibility analysis were verified using success and prediction rates. The success rate (AUC&thinsp;=&thinsp;0.918) and the prediction rate (AUC&thinsp;=&thinsp;0.901) of the LR model is higher than that of the ANN model (success rate (AUC&thinsp;=&thinsp;0.886) and prediction rate (AUC&thinsp;=&thinsp;0.877). These results indicate that the Regression Logistic (LR) model is the best model for determining landslide susceptibility in the study area.</p

    Search based software engineering: Trends, techniques and applications

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    © ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available from the link below.In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives. This article provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.EPSRC and E

    Accelerated expansion from structure formation

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    We discuss the physics of backreaction-driven accelerated expansion. Using the exact equations for the behaviour of averages in dust universes, we explain how large-scale smoothness does not imply that the effect of inhomogeneity and anisotropy on the expansion rate is small. We demonstrate with an analytical toy model how gravitational collapse can lead to acceleration. We find that the conjecture of the accelerated expansion being due to structure formation is in agreement with the general observational picture of structures in the universe, and more quantitative work is needed to make a detailed comparison.Comment: 44 pages, 1 figure. Expanded treatment of topics from the Gravity Research Foundation contest essay astro-ph/0605632. v2: Added references, clarified wordings. v3: Published version. Minor changes and corrections, added a referenc

    The effect of past use of oral contraceptive on bone mineral density, bone biochemical markers and muscle strength in healthy pre and post menopausal women

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    <p>Abstract</p> <p>Background</p> <p>during adulthood, most studies have reported that oral contraceptive (OC) pills had neutral, or possibly beneficial effect on bone health. We proposed this study of pre and post menopausal women assessing BMD, bone biochemical markers and physical performance among OC past users and comparable women who have never use Ocs.</p> <p>Methods</p> <p>A cross-sectional study comparing the bone density, bone biochemical markers (osteocalcin, CTX) and three measures to assess physical performance: timed get-up-and-go test "TGUG", five-times-sit-to-stand test "5 TSTS" and 8-feet speed walk "8 FSW" of users and never users OC. We were recruited 210 women who used OC for at least 2 years with that of 200 nonusers was carried out in pre and postmenopausal women (24-86 years).</p> <p>Results</p> <p>when analysing the whole population, BMD and biochemical markers values were similar for Ocs past users and control subjects. However when analysing the subgroup of premenopausal women, there was a statistically significant difference between users and never-users in osteocalcin (15,5 ± 7 ng/ml vs 21,6 ± 9 ng/ml; p = 0,003) and CTX (0,30 ± 0,1 ng/ml vs 0,41 ± 0,2 ng/ml; p = 0,025). This difference persisted after adjustment for age, BMI, age at menarche and number of pregnancies. In contrast, in post menopausal women, there was no difference in bone biochemical markers between OC users and the control. On the other hand OC past users had a significant greater performance than did the never users group. And when analysing the physical performance tests by quartile OC duration we found a significant negative association between the three tests and the use of OC more than 10 years.</p> <p>Conclusion</p> <p>the funding show no evidence of a significant difference in BMD between Ocs users and never user control groups, a decrease in bone turn over in OC pre menopausal users and a greater physical performances in patients who used OC up than 10 years.</p
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