561 research outputs found
The Hrushovski Property for Compact Special Cube Complexes
We show that any compact nonpositively curved cube complex embeds in a
compact nonpositively curved cube complex where each combinatorial
injective partial local isometry of extends to an automorphism of . When
is special and the collection of injective partial local isometries
satisfies certain conditions, we show that can be chosen to be special and
the embedding can be chosen to be a local isometry
A Simple PCRâRFLP Method for Genetic Phase Determination in Compound Heterozygotes
When susceptibility to diseases is caused by cis-effects of multiple alleles at adjacent polymorphic sites, it may be difficult to assess with confidence the genetic phase and identify individuals carrying the risk haplotype. Experimental assessment of genetic phase is still challenging and most population studies use statistical approaches to infer haplotypes given the observed genotypes. While these statistical approaches are powerful and have been proven very useful in large scale genetic population studies, they may be prone to errors in studies with small sample size, especially in the presence of compound heterozygotes. Here, we describe a simple and novel approach using the popular PCRâRFLP based strategy to assess the genetic phase in compound heterozygotes. We apply this method to two extensively studied SNPs in two clustered immune-related genes: The â308 (Gâ>âA) and the +252 (Aâ>âG) SNPs of the tumor necrosis factor (TNF) alpha and the lymphotoxin alpha (LTA) genes, respectively. Using this method, we successfully determined the genetic phase of these two SNPs in known compound heterozygous individuals and in every sample tested. We show that the A allele of TNF â308 is carried on the same chromosome as the LTA +252(G) allele
Environmental and landscape rehabilitation: case study for fresh stone treatment on big dams
The construction of big dams usually cause a severe environmental change at a local level, producing a considerable visual impact that must be remedied and the disturbed area must be rehabilitated and recovered, approaching the landscape prior to the dam construction. In this work, several assays were tested, with the purpose of finding a treatment for fresh cut granite that could be used as a general rock treatment for visual impact of fresh excavated rocks. Some organic mixtures were tried, using autochthonous lichens and moss, as well as chemical treatments, like acid or paint. Granite blocks were selected and five different treatments were applied to cover the fresh granitic blocks and trigger their colonization and aging. The experiment has been established on two groups of blocks, one submitted to irrigation three times a week and the other without irrigation. Each treatment had two repetitions per group. Two blocks for control were also established in each group to interpret the gaps of variation in comparison to the treated blocks. All the stone blocks were maintained in a greenhouse, with controlled temperature and humidity. The monitoring of the treatment was done by taking pictures every 20 days, that were analyzed using RGB color characteristics and parameters that shows the evolution of pigmentation of the blocks. The results of this study show that three or at least two out of the five tested treatments are recommended to use in the disturbed areas. Irrigation can be more useful for the first two to three weeks after treatmentsinfo:eu-repo/semantics/submittedVersio
Les arrangements de proximité sur les terres publiques : un choix délibéré ou une " question de survie " pour l'agriculture irriguée en Algérie ?
International audienceCe papier prĂ©sente l'Ă©tude de l'organisation actuelle des agriculteurs sur les terres publiques collectivisĂ©es. L'objectif Ă©tait de reconstituer, de maniĂšre participative, la situation actuelle et de co-construire des scĂ©narios d'Ă©volution des activitĂ©s agricoles dans la plaine irriguĂ©e de la Mitidja en AlgĂ©rie. L'analyse repose d'une part, sur nos enquĂȘtes de terrain menĂ©es sur un large Ă©chantillon d'exploitations agricoles collectives et, d'autre part, sur plusieurs ateliers participatifs impliquant des agriculteurs et des reprĂ©sentants d'institutions agricoles locales. Cette mĂ©thode nous a permis de valider avec les acteurs concernĂ©s les rĂ©sultats issus des enquĂȘtes portant sur les principales contraintes et les arrangements qui charpentent l'agriculture irriguĂ©e sur les terres publiques algĂ©riennes. L'ensemble des rĂ©formes qu'a connues le secteur agricole en AlgĂ©rie ainsi qu'un contexte socioĂ©conomique fragilisĂ© a donnĂ© lieu aujourd'hui Ă un Ă©ventail de dynamiques agricoles et d'arrangements parfois rapides et trĂšs Ă©loignĂ©s du schĂ©ma " thĂ©orique " tracĂ© par le ministĂšre de l'Agriculture. Le recours quasi systĂ©matique Ă la nappe souterraine en prĂ©sence d'un rĂ©seau collectif d'irrigation et le partage Ă l'amiable du foncier au sein des exploitations agricoles collectives constituent une partie " visible " de ces arrangements qui viennent combler, voire contourner, un cadre lĂ©gal inadaptĂ© ou rigide notamment en matiĂšre de lĂ©gislation fonciĂšre et d'accĂšs aux facteurs de production. L'Ă©valuation de cette dĂ©marche faite par les participants Ă©tait globalement trĂšs positive, montrant un changement de perception des acteurs les uns vis-Ă -vis des autres et un rĂ©el intĂ©rĂȘt pour la dĂ©marche de co-construction dans un espace de dialogue absent jusqu'alors. Nous avons abouti Ă une convergence " agriculteurs-institutionnels " sur l'activitĂ© agricole dans la Mitidja, notamment sur l'eau et le foncier; et Ă une vision partagĂ©e sur les scĂ©narios d'Ă©volution de l'agriculture dans la plaine de la Mitidja, principalement le dĂ©veloppement de nouvelles plantations d'agrumes. L'originalitĂ© de cette approche rĂ©side dans la combinaison des rĂ©sultats d'enquĂȘtes de terrain avec un travail de rĂ©flexion sur l'implication des acteurs, moteur du changement, dans l'Ă©laboration et l'exploration de ces scĂ©narios d'Ă©volution et les modes d'arrangements
Information transport by sine-Gordon solitons in microtubules
We study the problem of information propagation in brain microtubules. After
considering the propagation of electromagnetic waves in a fluid of permanent
electric dipoles, the problem reduces to the sine-Gordon wave equation in one
space and one time dimensions. The problem of propagation of information is
thus set.Comment: 3 page
Behavior of the parameters of microcrystalline silicon TFTs under mechanical strain
International audienceN-type and P-type microcrystalline silicon top-gate TFTs, processed directly on PEN plastic substrate at maximum temperature of 180 °C, were mechanically stressed. These TFTs were bent by different curvature radii varying between infinite (flat) and 0.5 cm. The tensile stress increases the electron mobility and the compressive stress decreases it. The tensile stress decreases the threshold voltage of N-type TFTs while the compressive stress increases it. These trends are inversed if the type of stress changes OR the type of TFTs changes. The total behavior under mechanical stress is exactly similar to that of single crystalline silicon MOSFETs in nano-scale technologies (90, 65, 45, 32 nm), where nano-scale stress is introduced in the goal to engineer the electrical parameters. The similarity originates from the microcrystalline silicon active layer that behaves like single crystalline silicon even if the stress effects are softened by the grain boundaries and the multiple crystalline orientations of the grains
Production of biocompatible gold nanoparticles for drug delivery using droplet based glass capillary microfluidic [Abstract]
Production of biocompatible gold nanoparticles for drug delivery using droplet based glass capillary microfluidic [Abstract
Thin film transistors fabricated by in-situ doped unhydrogenated polysilicon films obtained by solid phase crystallization
International audienceHigh mobility low temperature (†600°C) unhydrogenated in-situ doped polysilicon thin film transistors are made. Polysilicon layers are grown by a LPCVD technique and crystallized in vacuum by a thermal annealing. Source and drain regions are in-situ doped. Gate insulator is made of an APCVD silicon dioxide. Hydrogen passivation is not performed on the transistors. One type of transistors is made of two polysilicon layers, the other one is constituted of a single polysilicon layer. The electrical properties are better for transistors made of single polysilicon layer: a low threshold voltage (1.2 V), a subthreshold slope S = 0.7 V/dec, a high field effect mobility (â 100 cm2/Vs) and a On/Off state current ratio higher than 107 for a drain voltage Vds = 1 V. At low drain voltage, for both transistors, the Off state current results from a pure thermal emission of trapped carriers. However, at high drain voltage, the electrical behavior is different: in the case of single polysilicon TFTs, the current obeys the field-assisted (Poole-Frenkel) thermal emission model of trapped carriers while for TFTs made of two polysilicon layers, the higher Off state current results from a field-enhanced thermal emission
Effect of resonances on the transport properties of two-dimensional disordered systems
We study both analytically and numerically how the electronic structure and
the transport properties of a two-dimensional disordered system are modified in
the presence of resonances. The energy dependence of the density of states and
the localization length at different resonance energies and strengths of
coupling between resonances and random states are determined. The results show,
that at energy equals to the resonance energy there is an enhancement in the
density of states. In contrast, the localization length remains unaffected from
the presence of the resonances and is similar to the one of the standard
Anderson model. Finally, we calculate the diffusion constant as a function of
energy and we reveal interesting analogies with experimental results on light
scattering in the presence of Mie resonances.Comment: 4 pages, 4 figures, accepted in Phys. Rev. B (2000
Seismic risk in the city of Al Hoceima (north of Morocco) using the vulnerability index method, applied in Risk-UE project
The final publication is available at Springer via http://dx.doi.org/10.1007/s11069-016-2566-8Al Hoceima is one of the most seismic active regions in north of Morocco. It is demonstrated by the large seismic episodes reported in seismic catalogs and research studies. However, seismic risk is relatively high due to vulnerable buildings that are either old or donât respect seismic standards. Our aim is to present a study about seismic risk and seismic scenarios for the city of Al Hoceima. The seismic vulnerability of the existing residential buildings was evaluated using the vulnerability index method (Risk-UE). It was chosen to be adapted and applied to the Moroccan constructions for its practicality and simple methodology. A visual inspection of 1102 buildings was carried out to assess the vulnerability factors. As for seismic hazard, it was evaluated in terms of macroseismic intensity for two scenarios (a deterministic and probabilistic scenario). The maps of seismic risk are represented by direct damage on buildings, damage to population and economic cost. According to the results, the main vulnerability index of the city is equal to 0.49 and the seismic risk is estimated as Slight (main damage grade equal to 0.9 for the deterministic scenario and 0.7 for the probabilistic scenario). However, Moderate to heavy damage is expected in areas located in the newer extensions, in both the east and west of the city. Important economic losses and damage to the population are expected in these areas as well. The maps elaborated can be a potential guide to the decision making in the field of seismic risk prevention and mitigation strategies in Al Hoceima.Peer ReviewedPostprint (author's final draft
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