1,734 research outputs found
Convolutional Goppa Codes
We define Convolutional Goppa Codes over algebraic curves and construct their
corresponding dual codes. Examples over the projective line and over elliptic
curves are described, obtaining in particular some Maximum-Distance Separable
(MDS) convolutional codes.Comment: 8 pages, submitted to IEEE Trans. Inform. Theor
Synthesis, characterization of a new carbonylated zirconium metallocene using a dichloro-zirconocene derived from partially alkylated s-indacene
IndexaciĂłn: ScieloThis work describes the synthesis and characterization of new organometallic species, an unprecedented mononuclear zirconium complex bearing a tetraalkylated s-indacene ligand, and secondly, its respective dicarbonyl complex obtained by reduction with Mg/HgCl2. Theoretical calculations of these two compounds were carried out to gain further understanding of these novel molecular systems.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072009000300014&lng=es&nrm=is
Hysteroscopic Management of an Interstitial Ectopic Pregnancy
We report a case of an interstitial ectopic pregnancy successfully managed by hysteroscopy. We highlight the benefits of using hysteroscopy, a non-invasive procedure, to preserve fertility
Checklist of the centipedes (Chilopoda) of Hispaniola
Ten years have passed since the last checklist of Hispaniolan Chilopoda was done and the last bibliographic compendium was published. In this work we expand the former list of species and bibliography, update the taxonomic classification and provide an assessment on Chilobase records. A new intensive literature review was performed and both recent and formerly overlooked myriapodological works were included. The treatment of supraspecific taxonomic ranks was updated and follows Chilobase 2.0. This catalogue lists 4 fossil taxa as well as 24 extant species of centipedes from Hispaniola, 9 of which are endemic. For each extant species considered, there is information on Hispaniolan synonymies and geographic distribution. Included are some clarifications on synonymies and locality problems, and species with uncertain taxonomic status are indicated. Chilobase 2.0 was tested for completeness and accuracy. We propose several updates, grouped by incorrect species records, records not backed by known literature and species not under their currently accepted synonym. We also recommend chilopodologists to maintain active collaboration and send their updates to this useful database
Analysis of performance parameters of the smash in male and female professional padel
The aim of this study was to analyze the distribution and effectiveness of the different types of smash in professional padel according to the area and direction of the strokes and the gender. Through systematic observation, 1.015 smashes from eight finals (four men’s and four women’s) of the professional matches were analyzed. The smashes were categorized into four types of smash: tray, flat, topspin and off the wall. The results showed both men’s and women’s that the tray is the most used smash by padel players, presenting a percentage of point continuity of almost 90%. The flat and topspin smashes are the strokes that achieve the highest percentage of winning points (near 60%), although this efficiency decreases significantly when the players move away from the net area (p < 0.05), especially in the flat smash. Men perform a higher percentage of winning smashes than women, mainly in the flat smash (p = 0.02). Furthermore, with regards to direction, flat and off the wall smashes are predominantly down the line strokes and women perform significantly more cross court topspin smashes than men (p = 0.005). The results shown could be used to design tasks and exercises by padel coaches at professional players
SĂŤNTESIS Y CARACTERIZACIĂ“N DE COMPUESTOS DE COORDINACIĂ“N: UNA
El presente trabajo muestra los resultados exitosos en el desarrollo de un curso de laboratorio de quĂmica inorgánica mediante la implementaciĂłn del modelo de Aprendizaje por InvestigaciĂłn, como una estrategia integradora de conocimientos que permite a los estudiantes el desarrollo de competencias de reconocimiento, interpretaciĂłn y producciĂłn relacionadas con los procesos de sĂntesis de compuestos de coordinaciĂłn de interĂ©s en el área de la quĂmica inorgánica. El desarrollo riguroso de la metodologĂa cientĂfica condujo a la comprensiĂłn y aplicaciĂłn de las teorĂas de enlace de valencia y orbital molecular, la teorĂa de coordinaciĂłn de Werner y la teorĂa de campo cristalino; como tambiĂ©n principios de simetrĂa, teorĂa de grupos y espectroscopĂa infrarroja, IR
Checklist of the centipedes (Chilopoda) of Hispaniola
Ten years have passed since the last checklist of Hispaniolan Chilopoda was done and the last bibliographic compendium was published. In this work we expand the former list of species and bibliography, update the taxonomic classification and provide an assessment on Chilobase records. A new intensive literature review was performed and both recent and formerly overlooked myriapodological works were included. The treatment of supraspecific taxonomic ranks was updated and follows Chilobase 2.0. This catalogue lists 4 fossil taxa as well as 24 extant species of centipedes from Hispaniola, 9 of which are endemic. For each extant species considered, there is information on Hispaniolan synonymies and geographic distribution. Included are some clarifications on synonymies and locality problems, and species with uncertain taxonomic status are indicated. Chilobase 2.0 was tested for completeness and accuracy. We propose several updates, grouped by incorrect species records, records not backed by known literature and species not under their currently accepted synonym. We also recommend chilopodologists to maintain active collaboration and send their updates to this useful database.</p
An in-depth view of the microscopic dynamics of Ising spin glasses at fixed temperature
Using the dedicated computer Janus, we follow the nonequilibrium dynamics of
the Ising spin glass in three dimensions for eleven orders of magnitude. The
use of integral estimators for the coherence and correlation lengths allows us
to study dynamic heterogeneities and the presence of a replicon mode and to
obtain safe bounds on the Edwards-Anderson order parameter below the critical
temperature. We obtain good agreement with experimental determinations of the
temperature-dependent decay exponents for the thermoremanent magnetization.
This magnitude is observed to scale with the much harder to measure coherence
length, a potentially useful result for experimentalists. The exponents for
energy relaxation display a linear dependence on temperature and reasonable
extrapolations to the critical point. We conclude examining the time growth of
the coherence length, with a comparison of critical and activated dynamics.Comment: 38 pages, 26 figure
Aspectos a considerar en el diseño y ejecuciĂłn de espigones de baja cota : el caso del espigĂłn de FuentebravĂa
Los espigones de baja cota de coronaciĂłn se han utilizado con Ă©xito como obras necesarias para evitar la pĂ©rdida lateral de arena, en los casos en que se minimicen los efectos negativos que dichos espigones puedan causar en las playas cercanas. Han sido varios los espigones de baja cota de coronaciĂłn utilizados en el litoral gaditano (Playas de Santa MarĂa del Mar en Cádiz, Regla en Chipiona, La Costilla en Rota, y FuentebravĂa, en El Puerto de Santa MarĂa). Entre los factores a tener en cuenta en su diseño, destacan principalmente los siguientes aspectos (GĂłmez Pina, 2003): i) TĂ©cnicos, ii) Ambientales, iii) EconĂłmicos, iv) De integraciĂłn en el entorno, v) EstĂ©ticos, vi) Recreacionales. Todos estos aspectos deben abordarse de una forma integral, siendo los tres Ăşltimos—aunque puedan parecer de menor importancia—cruciales a la hora de obtener la aceptaciĂłn social, entre los distintos grupos que utilizan la playa
- …