Technical note: The effects of five different defaunation methods on biogeochemical properties of intertidal sediment

Various methods have been used to remove organisms from sediments to investigate structure and function of faunal assemblages in intertidal habitats. Nevertheless, little is known about how these treatments affect properties of the sediments themselves, although changing these properties may cause changes in the assemblages, independently of other hypotheses being tested. This study assesses the efficacy of defaunation and effect on selected biogeochemical properties of five different methods of defaunating soft muddy sediments in an estuary. The methods were removal and freezing of sediment, removal and oven-heating, freezing in situ with liquid N2, spraying with formalin and spraying with hydrogen peroxide. The first four of these methods have been used in previous studies, whilst the fifth was considered to be a potentially useful defaunator because it does not leave toxic residues. The first two methods required sediment to be brought back to the lab, disrupting the natural structure of the sediment; the last three were done in situ, with much less disturbance.  Variables measured to assess effects of the treatments on the sediment were amount of water, grain size, total carbohydrate, suspension index (relative erosion rate), erosion threshold, chlorophyll a and b, colloidal carbohydrate, Fo (minimal fluorescence) and Fv/ Fm (photosynthetic yield). There were no significant effects of any treatment on the first four variables. For the others, effects of defaunation varied from treatment to treatment and with time after treatment. Generally, the greatest disturbance was to the microphytobenthos (MPB, measured by chlorophyll and fluorescence) and related variables. For most treatments, recovery was rapid, but the effects of formalin and H2O2 persisted for a few days. Effects on physical properties of the sediment were mostly minor and insignificant. Removal and freezing or heating, however, caused major changes to the sediments because of the disturbances involved. Choosing the appropriate method of defaunation is very important if interpretations are not to be confounded between the effects of defaunation per se and any effects of changes to other biota (such as microphytobenthos) and/or the properties of sediments caused by the method used to defaunate experimental areas

D0--anti-D0 mixing results from BaBar by analysis of D0 --> K+ pi- pi0 Dalitz-plot regions

We present a preliminary search for D0--anti-D0 mixing using the decays D0 --> K+ pi- pi0, additionally presenting Dalitz-plot distributions and a measurement of the branching ratio for this mode. A new tagging technique is used to produce the doubly Cabibbo-suppressed Dalitz plot, which in turn is used to motivate the method used for the D-mixing search. We analyze 230.4fb-1 of data collected from the BaBar detector at the PEP-II collider. Assuming CP conservation, we find R_M < 0.054% with 95% confidence, and we estimate that the data are consistent with no mixing at a 4.5% confidence level. We present D-mixing results both with and without the assumption of CP conservation.Comment: 5 pages, 5 figures, Flavor Physics & CP Violation Conference, Vancouver, 200

Enhanced photosensitivity in tin-codoped germanosilicate optical fibres

Enhanced photosensitivity is found in Tin-codoped germanosilicate optical fibers. A photo-induced refractive index change (~1.4 x 10-3 times larger than that observed in pure germanosilicate fibers has been demonstrated. Unlike the technique of using Boron-codoping to enhance the photosensitivity of germanosilicate fibers, Tin-doping does not have a significant effect on fiber loss at the important telecommunication window of 1.55µm. High temperature stability of the gratings in Tin-codoped germanosilicate fibers is also much over Boron-codoped fibers

Design of a movil manipulator with optimum mechanical energy using differential evolution

En este trabajo se establece el problema de diseño cinemático y dinámico de los eslabones de un manipulador móvil como un problema de optimización numérica, con el objetivo de minimizar la energía mecánica del sistema en las posiciones críticas de un espacio de trabajo pre-establecido. Al cumplir con el objetivo propuesto se disminuye consecuentemente el consumo de energía que necesita el sistema de control durante su operación dentro del espacio de trabajo pre-establecido. Para dar solución al problema de optimización, se incorpora un mecanismo de explotación exhaustiva en el algoritmo tradicional de evolución diferencial, permitiendo mejorar la búsqueda dentro de una vecindad del espacio de diseño. Resultados en simulación muestran el desempeño del algoritmo. A su vez se muestra un menor consumo de energía del diseño resultante comparado con otros 3 diseños.In this work, the design of kinematic and dynamic parameters of links of a mobile manipulator is stated as a numerical optimization problem (NOP). The NOP aims to minimize the mechanical energy of the system in critical positions given by the vertices of a workspace and consequently reduce the energy consumption of the control system during its operation in the workspace. An exhaustive exploitation mechanism is included in the traditional differential evolution algorithm to improve the search into a neighborhood in the design space. Simulation results show the performance of the algorithm. The resulting design shows less energy consumption than other three designs.Peer Reviewe

O Turismo, a Hotelaria e as Tecnologias Digitais

Em relação às ferramentas e estratégias utilizadas pelos hotéis na web, é importante que estas sejam adequadas ao mercado turísticos para que assim se possa obter sucesso através das novas tecnologias, pois quando bem elaborados e desenvolvidos de maneira correta, os hotéis conseguirão agregar valor aos serviços de hospedagem, tornando-se mais competitivos. As perspectivas de utilização e consumo através da web relacionadas com o setor hoteleiro crescerão ainda mais nos próximos anos, porém a qualidade da informação disponível torna-se um diferencial em relação aos concorrentes em virtude da quantidade de sites na web e da exigência cada vez maior por parte dos consumidores. Palavras-chave: Web (Sistema de recuperação da informação), Concorrência, Estratégia

Estrategia de enseñanza y aprendizaje para el estudio de los elementos característicos de la parábola

El presente trabajo da cuenta de una estrategia didáctica para innovar el anquilosado proceso de enseñanza-aprendizaje de la parábola, en el Bachillerato General José Clemente Orozco de Tehuacán, Puebla, México. La propuesta está estructurada con diferentes actividades que se desarrollan en dieciséis sesiones-hora clase de 60 minutos cada una. Los resultados obtenidos en cada actividad muestran el proceso gradual del aprendizaje. Finalmente, se acota que los estudiantes aplicaron los conocimientos adquiridos en la construcción de una cocina parabólica solar y en este trabajo se muestran también las evidencias del funcionamiento eficiente y eficaz de la propositio

CRISPRED: A data pipeline for the CRISP imaging spectropolarimeter

The production of science-ready data from major solar telescopes requires expertise beyond that of the typical observer. This is a consequence of the increasing complexity of instruments and observing sequences, which require calibrations and corrections for instrumental and seeing effects that are not only difficult to measure, but are also coupled in ways that require careful analysis in the design of the correction procedures. Modern space-based telescopes have data-processing pipelines capable of routinely producing well-characterized data products. High resolution imaging spectropolarimeters at ground-based telescopes need similar data pipelines.We present new methods for flat-fielding spectropolarimetric data acquired with telecentric Fabry-Perot instruments and a new approach for accurate camera co-alignment for image restoration. We document a procedure that forms the basis of current state-of-the-art processing of data from the CRISP imaging spectropolarimeter at the Swedish 1 m Solar Telescope (SST). By collecting, implementing, and testing a suite of computer programs, we have defined a data reduction pipeline for this instrument. This pipeline, CRISPRED, streamlines the process of making science-ready data.It is implemented and operated in IDL, with time-consuming steps delegated to C.CRISPRED will also be the basis for the data pipeline of the forthcoming CHROMIS instrument. © ESO, 201

Project fuse aerial suppression experiments

Preprin

Fiabilidad y validez de las mediciones en hombro y codo: análisis de una aplicación de Android y un goniómetro

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.Carta al EditorRevisión por pare