Plantas medicinales de Argentina con actividad gastroprotectora

The gastro protective activity of aqueous extracts from 11 plants native to Argentina was evaluated on ethanol-inducedgastric ulcer model in mice: Aloysia gratissima, Artemisia annua, Calendula offi cinalis, Gaillardia megapotamica,Maytenus ilicifolia, Parthenium hysterophorus, Portulaca oleracea, Rumex obtusifolius, Solanum eleagnifolium,Solidago chilensis and Spartium junceum. The results were expressed in terms of an Ulcer Index (UI), based on themeasurement of the length of the gastric lesions produced. Pharmacological assays demonstrated that aqueous extractsfrom all the plants, administered in oral form, showed signifi cant antiulcerogenic activity (P < 0.01). It has already beenestablished that among other compounds, the fl avonoids possess, gastro protective properties. As some of the aqueousextracts contain these constituents, the partial antiulcer activity found could be attributed to their presence. The mechanisminvolved in this effect has not been entirely elucidated and as a fi rst stage in its analysis, extracts should befractionated in order to better determine the role of each component.Se evaluó la actividad gastroprotectora de extractos acuosos de 11 plantas que se desarrollan en Argentina: Aloysiagratissima, Artemisia annua, Calendula offi cinalis, Gaillardia megapotamica, Maytenus ilicifolia, Parthenium hysterophorus,Portulaca oleracea, Rumex obtusifolius, Solidago chilensis, Solanum eleagnifolium y Spartium junceum frentea un modelo de úlcera gástrica inducida por etanol en ratones. Los resultados se expresaron en términos de Indicede Ulcera (IU), el cual se estableció de acuerdo a la longitud de las lesiones gástricas. Los ensayos farmacológicosdemostraron que los extractos acuosos de todas las plantas, administrados oralmente, exhibieron una signifi cativaactividad antiulcerosa (P < 0,01). Es sabido que los fl avonoides, entre otros compuestos, poseen reconocidas propiedadesgastroprotectoras. Debido a que algunos de los extractos contienen dichos componentes, parte de la actividadantiulcerosa podría deberse a su presencia. El mecanismo involucrado en este efecto no está totalmente elucidado.Por lo tanto, en una primera etapa, los extractos deberán ser fraccionados y analizados para determinar su modode acción y evaluar adecuadamente la actividad gastroprotectora de estas planta

A general relativistic model for the light propagation in the gravitational field of the Solar System: the dynamical case

Modern astrometry is based on angular measurements at the micro-arcsecond level. At this accuracy a fully general relativistic treatment of the data reduction is required. This paper concludes a series of articles dedicated to the problem of relativistic light propagation, presenting the final microarcsecond version of a relativistic astrometric model which enable us to trace back the light path to its emitting source throughout the non-stationary gravity field of the moving bodies in the Solar System. The previous model is used as test-bed for numerical comparisons to the present one. Here we also test different versions of the computer code implementing the model at different levels of complexity to start exploring the best trade-off between numerical efficiency and the micro-arcsecond accuracy needed to be reached.Comment: 40 pages, 5 figures. Accepted for publication on The Astrophysical Journal. Manuscript prepared with AASLaTeX macros v.5.

Comparative study of design: application to Engineering Design

A recent exploratory study examines design processes across domains and compares them. This is achieved through a series of interdisciplinary, participative workshops. A systematic framework is used to collect data from expert witnesses who are practising designers across domains from engineering through architecture to product design and fashion, including film production, pharmaceutical drugs, food, packaging, graphics and multimedia and software. Similarities and differences across domains are described which indicate the types of comparative analysis we have been able to do from our data. The paper goes further and speculates on possible lessons for selected areas of engineering design which can be drawn from comparison with processes in other domains. As such this comparative design study offers the potential for improving engineering design processes. More generally it is a first step in creating a discipline of comparative design which aims to provide a new rich picture of design processes

Tidy dataset of the experimental design of the optimization of the alkali degumming process of Bombyx mori silk.

Silk fibroin is the structural fiber of the silk filament and it is usually separated from the external protein, named sericine, by a chemical process called degumming. This process consists of an alkali bath in which the silk cocoons are boiled for a determined time. It is also known that the degumming process impacts the property of the outcoming silk fibroin fibers. In this work, we described the dataset obtained from a Design of Experiment (DoE) screening made on the alkali degumming. Four process factors were considered: the number of degumming baths, the process time, the process temperature, and the salt concentration. The data on the properties of the silk fibroin fibers were collected. In particular, the molecular weight was obtained by gel permeation chromatography (GPC), the mechanical data by tensile test and the secondary structure by Fourier Infrared Transform Spectroscopy (FTIR)

The GSC-II-based survey of ancient cool white dwarfs I. The sample of spectroscopically confirmed WDs

The GSC-II white dwarf survey was designed to identify faint and high proper motion objects, which we used to define a new and independent sample of cool white dwarfs. With this survey we aim to derive new constraints on the halo white dwarf space density. Also, these data can provide information on the age of thick disk and halo through the analysis of the luminosity function. On the basis of astrometric and photometric parameters, we selected candidates with mu > 0.28 as/yr and R_F > 16 in an area of 1150 square degrees. Then, we separated white dwarfs from late type dwarfs and subdwarfs by means of the reduced proper motion diagram. Finally, spectroscopic follow-up observations were carried out to confirm the white dwarf nature of the selected candidates. We found 41 white dwarfs of which 24 are new discoveries. Here we present the full sample and for each object provide positions, absolute proper motions, photometry, and spectroscopy.Comment: 14 pages, 7 figures, submitted to A&

Planar Thinned Arrays: Optimization and Subarray Based Adaptive Processing

A new approach is presented for the optimized design of a planar thinned array; the proposed strategy works with single antenna elements or with small sets of different subarray types, properly located on a planar surface. The optimization approach is based on the maximization of an objective function accounting for side lobe level and considering a fixed number of active elements/subarrays. The proposed technique is suitable for different shapes of the desired output array, allowing the achievement of the desired directivity properties on the corresponding antenna pattern. The use of subarrays with a limited number of different shapes is relevant for industrial production, which would benefit from reduced design and manufacturing costs. The resulting modularity allows scalable antenna designs for different applications. Moreover, subarrays can be arranged in a set of subapertures, each connected to an independent receiving channel. Therefore, adaptive processing techniques could be applied to cope with and mitigate clutter echoes and external electromagnetic interferences. The performance of adaptive techniques with subapertures taken from the optimized thinned array is evaluated against assigned clutter and jamming scenarios and compared to the performance achievable considering a subarray based filled array with the same number of active elements

Testing general relativity by micro-arcsecond global astrometry

The global astrometric observations of a GAIA-like satellite were modeled within the PPN formulation of Post-Newtonian gravitation. An extensive experimental campaign based on realistic end-to-end simulations was conducted to establish the sensitivity of global astrometry to the PPN parameter \gamma, which measures the amount of space curvature produced by unit rest mass. The results show that, with just a few thousands of relatively bright, photometrically stable, and astrometrically well behaved single stars, among the ~10^9 objects that will be observed by GAIA, \gamma can be estimated after 1 year of continuous observations with an accuracy of ~10^{-5} at the 3\sigma level. Extrapolation to the full 5-year mission of these results based on the scaling properties of the adjustment procedure utilized suggests that the accuracy of \simeq 2x10^{-7}, at the same 3\sigma level, can be reached with \~10^6 single stars, again chosen as the most astrometrically stable among the millions available in the magnitude range V=12-13. These accuracies compare quite favorably with recent findings of scalar-tensor cosmological models, which predict for \gamma a present-time deviation, |1-\gamma|, from the General Relativity value between 10^{-5} and 10^{-7}.Comment: 7 pages, 2 figures, to be published in A&

Linearity in the non-deterministic call-by-value setting

We consider the non-deterministic extension of the call-by-value lambda calculus, which corresponds to the additive fragment of the linear-algebraic lambda-calculus. We define a fine-grained type system, capturing the right linearity present in such formalisms. After proving the subject reduction and the strong normalisation properties, we propose a translation of this calculus into the System F with pairs, which corresponds to a non linear fragment of linear logic. The translation provides a deeper understanding of the linearity in our setting.Comment: 15 pages. To appear in WoLLIC 201