389 research outputs found
The fate of water in the oasis of Ouakda between traditional systems and modern (Region of Béchar, Southwest, Algeria)
One of the subjects that touch the field of environment is undoubtedly the traditional catchment systems and drainage divide in the oasis. The ancestral techniques such as wells chadouf, quanat, Khettara and foggaras have protected the oasis and the man in the past. These techniques were used in an arid middle by the oasis dwellers and resisted to a hostile climate for centuries. In spite of the low rainfall in the region of our oasis, the oasis dwellers of Ouakda through their intelligence, they were able to cultivate their land without disturbing a fragile ecosystem through exploitation of groundwater table thanks to the use of foggaras with the small distance which does not exceed 100 m. But the intervention of modern systems of water catchment like deep boreholes which overexploiting nonrenewable tablecloths and the pumps large capacity, the man has completely destroyed a clean environment. Today, thanks to these pumping, the groundwater level has dropped considerably; soil salinity is remarkable on all the parcels of the old palm grove and the Oued. We try in this Article to study the history of traditional techniques of water catchments in the oasis of Ouakda, to do a comparison between the ancestral systems used in the another oasis in this oasis, to study the impact of the motor pumps on the degradation of traditional systems and detrimental effects (Soil salinity and the phenomenon of lowering of the groundwater) after the use of modern techniques of water catchment.Keywords: Oasis, Ouakda, Foggara, Wells, Chadouf, motor pump
Near-Optimal Quantum Algorithms for Multivariate Mean Estimation
We propose the first near-optimal quantum algorithm for estimating in
Euclidean norm the mean of a vector-valued random variable with finite mean and
covariance. Our result aims at extending the theory of multivariate
sub-Gaussian estimators to the quantum setting. Unlike classically, where any
univariate estimator can be turned into a multivariate estimator with at most a
logarithmic overhead in the dimension, no similar result can be proved in the
quantum setting. Indeed, Heinrich ruled out the existence of a quantum
advantage for the mean estimation problem when the sample complexity is smaller
than the dimension. Our main result is to show that, outside this low-precision
regime, there is a quantum estimator that outperforms any classical estimator.
Our approach is substantially more involved than in the univariate setting,
where most quantum estimators rely only on phase estimation. We exploit a
variety of additional algorithmic techniques such as amplitude amplification,
the Bernstein-Vazirani algorithm, and quantum singular value transformation.
Our analysis also uses concentration inequalities for multivariate truncated
statistics.
We develop our quantum estimators in two different input models that showed
up in the literature before. The first one provides coherent access to the
binary representation of the random variable and it encompasses the classical
setting. In the second model, the random variable is directly encoded into the
phases of quantum registers. This model arises naturally in many quantum
algorithms but it is often incomparable to having classical samples. We adapt
our techniques to these two settings and we show that the second model is
strictly weaker for solving the mean estimation problem. Finally, we describe
several applications of our algorithms, notably in measuring the expectation
values of commuting observables and in the field of machine learning.Comment: 35 pages, 1 figure; v2: minor change
The knowledges of traditional irrigation in the oasis of Kerzaz in southwest Algerian: Legacy and development
In the valley of Saoura, the demand for water for irrigation has increased significantly and rapidly, it requires mobilization and rational and intensive use of all existing water sources like the groundwater which are the only source of drinking water supply and irrigation in the region and the protection of the large vein that feeds the Saoura and bearing his name "oued Saoura". Oasis Kerzaz is amongst the the most celebrated oasis and the biggest of valley of Saoura , it now suffers from several impediments to their development as: the scarcity of irrigation water, land abandonment, the silting up, the chunking and the exiguity of agricultural land, the food nature of agricultural activity and incurable diseases of crops.Keywords: palm grove; well; Chadouf; Khottara; motorpump; Saoura
Semi-Automated Image Analysis Methodology to Investigate Intracellular Heterogeneity in Immunohistochemical Stained Sections
The discovery of tissue heterogeneity revolutionized the existing knowledge regarding the cellular, molecular, and pathophysiological mechanisms in biomedicine. Therefore, basic science investigations were redirected to encompass observation at the classical and quantum biology levels. Various approaches have been developed to investigate and capture tissue heterogeneity; however, these approaches are costly and incompatible with all types of samples. In this paper, we propose an approach to quantify heterogeneous cellular populations through combining histology and images processing techniques. In this approach, images of immunohistochemically stained sections are processed through color binning of DAB-stained cells (in brown) and non-stained cells (in blue) to select cellular clusters expressing biomarkers of interest. Subsequently, the images were converted to a binary format through threshold modification (threshold 60%) in the grey scale. The cell count was extrapolated from the binary images using the particle analysis tool in ImageJ. This approach was applied to quantify the level of progesterone receptor expression levels in a breast cancer cell line sample. The results of the proposed approach were found to closely reflect those of manual counting. Through this approach, quantitative measures can be added to qualitative observation of subcellular targets expression
Variations in pre-analytical FFPE sample processing and bioinformatics: challenges for next generation molecular diagnostic testing in clinical pathology
Advances in cellular pathology techniques will improve diagnostic medicine. However, such improvements have to overcome many challenges including variations in pre-analytical sample processing, bioinformatics data analysis and clinical interpretation of data. In order to resolve such challenges, bioinformatics needs to become more tightly coupled to the experimental methodology development
Molecular characterisation of FFPE pancreatic tumours treated with 5-Fluorouracil (5-FU) and sonodynamic therapy (SDT) using whole transcriptome analysis
Calculations of Longitudinal Form Factors of p-Shell Nuclei, Using Enlarged Model Space Including Core-Polarization Effects with Realistic Two-Body Effective Interaction
Protagonisten und Antagonisten : Eine Studie über Schillers Tragödientheorie und ihre Verwendung in drei seiner Dramen ; Die Räuber, Maria Stuart und Die Braut von Messina
Es handelt sich bei dieser Dissertation um die Tragödientheorie von Friedrich Schiller. Die Arbeit ist in einer Einleitung, drei Kapiteln und einem Schlusswort untertitelt. In der Einleitung behandle ich die verschiedenen Theorien und Philosophien von Aristoteles über Schakespear, die französischen Klassiker, Kant bis hin zur Tragödientheorie von Schiller. Im ersten Kapitel analysiere ich das Drama "Die Räuber" insbesondere die Charaktere Karl und Franz Moor, die gestörte Vaterwelt und die religiösen Anspielungen im Drama.
Im zweiten Kapitel behandle ich das Drama "Maria Stuart". Neben einer Analyse der beiden Hauptcharaktere (Elisabeth und Maria) behandle ich die Begegnung der beiden Königinnen und versuche am Ende zu zeigen, warum und wie Maria als eine erhabene Figur und eine shcöne Seele gilt.
Im dritten Kapitel behandle ich das Drama "Die Braut von Messina". Hier erforsche ich die Rolle des Chores im Drama und versuche zu zeigen, dass Don Cesar keine erhabene Figur ist.
Im Schlusswort legte ich alle Bemerkungen und Schlussfolgerungen, die ich gesammelt habe, dar
Effect of activated alloys on hydrogen discharge kinetics of MgH2 nanocrystals
This is the post-print version of the final paper published in Journal of Alloys and Compounds. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2007 Elsevier B.V.Activated alloys synthesized by arc-melting were examined as catalysts for improving the hydrogen sorption characteristics of nanostructured magnesium hydride, proposed as a reversible hydrogen storage material. The MgH2-catalyst absorbing materials were prepared by ball milling of pure MgH2 with hydrided Zr47Ni53, Zr9Ni11, and other investigated alloys. The nanostructured MgH2-intermetallic systems were tested at 250 °C and catalyst addition of eutectoid Zr47Ni53 resulted in the fastest desorption time and highest initial desorption rate. Also, the catalyzed Mg-hydride with activated Zr9Ni11 and Zr7Ni10 phases showed fast desorption kinetics. Moreover, the results demonstrated that the composition of dispersed ZrxNiy catalysts has a strong influence on the amount of accumulated hydrogen and desorption rate of Mg-nanocomposite.National Research Council Canad
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