Alpine surface soil movement

August 1969.Includes bibliographical references (pages 107-119).Covers not scanned.Print version deaccessioned 2021.During 1967 and 1968 a study was conducted to determine the rate and type of alpine surface soil movement in the vicinity of Crown Point, Roosevelt National Forest in northcentral Colorado. Five different colors of fluorescent pigments were used successfully to index the movement of soil particles quantitatively and qualitatively. Sediment was collected from 32 micro-runoff collectors over the w inter and snowmelt period of 1968, and over the summer period of the same year. Rates and patterns of actual soil particle movement were obtained from 15 transects (each about 15 meters long), representing the different site characteristics. Results indicated that creep erosion was the most important mechanism of soil movement in the alpine. On sites exposed to wind action, wind erosion was responsible for movement of soil particles less than 2 mm in size. Snow deposition, frost, rain-drops, wind, grazing, slope, vegetation and microtopography were the most important factors in accounting for surface soil movement in this alpine area

Combinaison de deux méthodes d'analyse de sensibilité

L’objectif de ce travail est de mettre en place une méthode d’analyse de sensibilité paramétrable, pour qu’elle puisse être utilisée avec différentes méthodes d’aide à la décision multicritères, qui génère des résultats exacts en un temps raisonnable. Afin d’atteindre notre objectif, nous avons utilisé une méthode d’analyse de stabilité de (Vetschera, 1986). Cette méthode a été présentée à l’origine pour Electre I, nous l’avons adapté à Electre II. Les résultats retournés par cette méthode avec Electre II seront utilisés pour l’analyse de sensibilité. Nous avons expérimenté la méthode d’analyse de sensibilité de (Ben Mena, 2001). Cette méthode détermine la sensibilité des paramètres d’Electre III. Suite à plusieurs expérimentations à l’aide du logiciel MCDM, nous avons pu améliorer la méthode de Ben Mena. Nous avons adapté notre nouvelle méthode à Electre II. À la fin, nous avons combiné les deux méthodes pour avoir une méthode d’analyse de sensibilité précise, rapide et qui ne demande pas une intervention humaine pour fixer les paramètres

Identification d'espèces végétales par une description géométrique locale d'images de feuilles

Plant species identification, usually performed by specialists, is based on the observation of its organs and mostly on visual criteria. Thanks to its ease of acquisition, the leaf is the most used organ. In addition, it contains important information on the taxonomy of the plant. This enables the use of computer vision and pattern recognition techniques for developing an automatic recognition process of the plant species from a leaf image. We introduce a new approach to identify plant species, based on the description of the following leaf characteristics : its shape, its salient points and its venation. First, the shape of the leaf is represented by local descriptors associated to a set of points sampled on the contour. Different multi-scale triangular representations are introduced and compared. To describe the salient points of the leaf, we propose a shape context based representation. Finally, the venation is extracted by detecting elementary linear structures with morphological tools. The venation network is described by its main directions and its spatial distribution in the context of the leaf boundary. A local matching method is used for all descriptors. Evaluations, conducted on six publicly available plant identification benchmarks, show that our approaches identify the plant species of the leaf in most of the cases and that the late fusion of the proposed descriptors improves the identification process.Il est nécessaire de reconnaître les espèces végétales afin de préserver la biodiversité des écosystèmes. L’identification d’une plante, habituellement effectuée par les experts, se base sur l’observation de ses organes et en majeure partie sur des critères visuels. La feuille est l’organe le plus utilisé grâce à sa facilité d’acquisition. De plus, celle-ci contient une information importante sur la taxonomie de la plante. Ceci permet d’envisager d’utiliser l’analyse d’images pour élaborer un processus de reconnaissance automatique de l’espèce végétale à partir de la donnée d’une image de feuille. Nous introduisons une nouvelle approche d’identification d’espèces végétales, basée sur la description des caractères foliaires suivants : la forme, les points saillants et la nervation. En premier lieu, la forme de la feuille est représentée par des descripteurs locaux associés aux points échantillonnés sur le contour. Différentes représentations triangulaires multi-échelle sont introduites et comparées. Pour décrire les points saillants de la feuille, nous proposons une représentation dérivée du contexte de forme (Shape Context). Finalement, la nervation est extraite par la détection de structures linéaires élémentaires avec des outils morphologiques. Le réseau de nervures extrait est décrit par ses directions principales et sa répartition spatiale dans le contexte de la surface de la feuille.Pour tous les descripteurs, une méthode de mise en correspondance locale est utilisée. Des évaluations, menées sur six bases de feuilles publiques, montrent que nos approches permettent généralement d’identifier l’espèce végétale de la feuille et que la fusion tardivedes descripteurs augmente la précision de l’identification

Left Ventricular Apical Aneurysm Post Myocardial Infarction In MRI: About a Case

Left ventricular aneurysm is a dangerous mechanical complication of transmural myocardial infarction caused by left anterior descending coronary artery occlusion. Cardiac imaging, dominated by MRI plays a key role in characterization of this entity. Medications or surgery lower the risk of a ruptured ventricular aneurysm.  We report the case of a left ventricular apical aneurysm post myocardial infarction in a 65-year-old patient after an anterior myocardial infraction.

Biología reproductiva de Diplodus sargus sargus en el golfo de Túnez (Mediterráneo)

The sexual activity of Diplodus sargus sargus in the Gulf of Tunis takes place from January to May. Spawning occurs in spring (March to May), as the water temperature rises from 15 to 18°C, just after the winter minimum. The spawning period increases as the latitude decreases. The overall male to female ratio was statistically different from unity. Size at sexual maturity (TL50) was 21 cm (4 years old). The length-weight relationship for all individuals was described by the following parameters: a = 0.015 and b = 3.051. D. s. sargus from the Gulf of Tunis is a rudimentary hermaphrodite with partial protandry.La actividad sexual de Diplodus sargus sargus del golfo de Túnez tiene lugar de enero a mayo. La puesta tiene lugar en primavera (marzo a mayo), cuando la temperatura del agua sube de 15 a 18°C, justo tras el mínimo invernal. A medida que la latitud decrece se observa un periodo reproductivo progresivamente más extenso. La relación machos/hembras fue significativamente distinta de uno. La talla de madurez sexual (TL50) fue 21 cm (4 años). La relación talla-peso para todos los individuos se describió por los siguientes parámetros: a = 0.015 y b = 3.051. D. s. sargus del golfo de Túnez es un a hermafrodita rudimentario con proterandría parcial.

Resistless electron beam lithography process for the fabrication of sub-50 nm silicide structures

We report on a study of the fabrication of submicron silicide structures with a resistless lithography technique. Several different metals can be used as a basis for producing silicide using this method; in this work, results will be discussed for both platinum and nickel silicide. The feasibility of producing nanostructures using polycrystalline silicon as a base growth layer for metal–oxide– semiconductor, and other device applications have also been demonstrated. Threshold doses for this method for submicron lines (<50 nm) and square areas were obtained in order to establish a framework for the fabrication of more complex devices. Preliminary electrical measurements were carried out which indicate that the resistivity of the silicide is 45 [mu omega] cm, and that the barrier height of the silicide/(high resistivity silicon) interface is 0.56 eV

Cerebellar stroke complicating coronary catheterization: a case report

Cerebrovascular events are rare but devastating events that can complicate any coronary intervention. In the vast majority of cases, they involve major cerebral arteries. We report the case of a 56-year-old woman admitted for unstable angina associated with severe left systolic dysfunction. She developed moderate cerebellar stroke while undergoing percutaneous coronary intervention, with a national institutes of health stroke scale score of 5. Immediate systemic thrombolysis was performed, but her neurological status deteriorated. A large hemorrhagic transformation was then diagnosed, and she died despite surgical intervention. Periprocedural strokes are marred with high morbidity and mortality, therefore preventionis key, as many risk factors can be controlled or mitigated. Our patient presented many of these factors; they can be procedure-related (transfemoral approach, anticoagulation) or patient-related (age, diabetes mellitus, uncontrolled hypertension, diffuse atherosclerosis)

Edad y crecimiento de Spondyliosoma cantharus (Sparidae) en el Golfo de Túnez

Age and the growth of the black seabream Spondyliosoma cantharus (Linnaeus, 1758) from the Gulf of Tunis were investigated using scales and otoliths. The length-weight relationship showed that the growth rates were isometric for females whereas males and the whole sample present a positive allometry. The monthly evolution in marginal increment data of scales and otoliths revealed that only one annulus is formed per year in April. Fish length and radii of the scales or otoliths were closely correlated. The von Bertalanffy growth equation was fitted on mean back-calculated length-at-age data, resulting in the parameter values L∞=35.4 cm, k=0.15 y–1 and t0=–0.19 y for scales and L∞=38.6 cm, k=0.10 y–1 and t0=–0.14 y for otoliths. Parameters estimated from scale and otoliths were significantly similar. However, taking into consideration the lower standard deviations of means for estimates based on otolith readings and the higher variance explained by the regression line fitted to otoliths, the latter seem to be more appropriate for ageing S. cantharus. The maximum age of the black seabream of the Gulf of Tunis is 10 years. Large discrepancies in growth parameters between geographic areas are the result of different growth patterns.Se han investigado la edad y el crecimiento de la cántara Spondyliosoma cantharus (Linnaeus, 1758) del Golfo de Túnez a partir de la lectura de las escamas y los otolitos. La relación talla-peso revela que las tasas de crecimiento son isométricas en las hembras, mientras que los machos y en toda la muestra existe una alometría positiva. La evolución mensual de los incrementos marginales de las escamas y los otolitos muestra que se forma un solo anillo anual en abril. La correlación entre la longitud de los peces y el radio de las escamas o los otolitos es muy elevada. La ecuación de crecimiento de von Bertalanffy se ha ajustado a la media talla-edad retrocalculada resultando en los siguientes valores para los parámetros de las escamas (L∞=35.4 cm, k=0.15 año–1, t0=–0.19 año) y los otolitos (L∞=38.6 cm, k=0.10 año–1, t0=–0.14 año). Los parámetros estimados a partir de las escamas y los otolitos resultaron significativamente similares. Sin embargo, teniendo en cuenta que las desviaciones estándar de las medias en las estimas son más bajas, y que la varianza explicada es mayor en la regresión ajustada a los otolitos, la lectura de los otolitos parece ser la más apropiada para datar la edad de S. cantharus. La edad máxima de la cántara del Golfo de Túnez es de 10 años. Las grandes diferencias en los parámetros de crecimiento entre áreas geográficas se deben a diferentes pautas de crecimiento

A shape-based approach for leaf classification using multiscale triangular representation

International audienceIn this paper we introduce a new multiscale shape-based approach for leaf image retrieval. The leaf is represented by local descriptors associated with margin sample points. Within this local description, we study four multiscale triangle representations: the well known triangle area representation (TAR), the triangle side lengths representation (TSL) and two new representations that we denote triangle oriented angles (TOA) and triangle side lengths and angle representation (TSLA). Unlike existing TAR approaches, where a global matching is performed, the similarity measure is based on a locality sensitive hashing of local descriptors. The proposed approach is invariant under translation, rotation and scale and robust under partial occlusion. Evaluations made on four public leaf datasets show that our shape-based approach achieves a high retrieval accuracy w.r.t. state-of-art methods

Advanced shape context for plant species identification using leaf image retrieval

International audienceThis paper presents a novel method for leaf species identification combining local and shape-based features. Our approach extends the shape context model in two ways. First of all, two different sets of points are distinguished when computing the shape contexts: the voting set, i.e. the points used to describe the coarse arrangement of the shape and the computing set containing the points where the shape contexts are computed. This representation is enriched by introducing local features computed in the neighborhood of the computing points. Experiments show the effectiveness of our approach