5,247 research outputs found
The double of the doubles of Klein surfaces
A Klein surface is a surface with a dianalytic structure. A double of a Klein
surface is a Klein surface such that there is a degree two morphism (of
Klein surfaces) . There are many doubles of a given Klein
surface and among them the so-called natural doubles which are: the complex
double, the Schottky double and the orienting double. We prove that if is a
non-orientable Klein surface with non-empty boundary, the three natural
doubles, although distinct Klein surfaces, share a common double: "the double
of doubles" denoted by . We describe how to use the double of doubles in
the study of both moduli spaces and automorphisms of Klein surfaces.
Furthermore, we show that the morphism from to is not given by the
action of an isometry group on classical surfaces.Comment: 14 pages; more details in the proof of theorem
Self-assembly of multi-component fluorescent molecular logic gates in micelles
A recent strategy for developing supramolecular
logic gates in water is based on combinations
of molecules via self-assembly with surfactants, which
eliminates the need for time-consuming synthesis. The
self-assembly of surfactants and lumophores and receptors
can result in interesting properties providing cooperative
e ffects useful for molecular information processing
and other potential applications such as drug delivery
systems. This article highlights some of the recent advancements
in supramolecular information processing
using microheterogeneous media including micelles in
aqueous solution.peer-reviewe
Enantiomeric Ratio Changes of Terpenes in Essential Oils from Hybrid Eucalyptus grandis × E. tereticornis and its Pure Species
Some Eucalyptus species produce oils with biological activities and the effect of their interspecifc hybridization on the enantiomeric composition of terpenes has not been reported. The enantiomeric excesses of monoterpenes in the essential oil of Eucalyptus grandis × E. tereticornis and its parental taxa were determined by gas chromatography-mass spectrometry (GC-MS), and to resolve coelutions problems by preparative high performance liquid chromatography (HPLC)and GC-MS with two columns in series. The essential oil composition of the hybrid presented qualitative and quantitative differences with the composition of its parental taxa. Great differences were found for the enantiomeric ratio in monoterpene alcohols among the three essential oils. Our results suggest that the enantiomeric analysis can be a reliable method for the study of how theinterspecifc hybridization can module the enantiomeric chemical profle in Eucalyptus essential oils. These results suggest the use of interspecifc hybridization to improve or expand the source of bioactive compounds.Fil: Naspi, Cecilia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Alvarez Costa, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Lucia, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Gonzalez Audino, Paola Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Masuh, Hector Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentin
Astrocomp: a web service for the use of high performance computers in Astrophysics
Astrocomp is a joint project, developed by the INAF-Astrophysical Observatory
of Catania, University of Roma La Sapienza and Enea. The project has the goal
of providing the scientific community of a web-based user-friendly interface
which allows running parallel codes on a set of high-performance computing
(HPC) resources, without any need for specific knowledge about parallel
programming and Operating Systems commands. Astrocomp provides, also, computing
time on a set of parallel computing systems, available to the authorized user.
At present, the portal makes a few codes available, among which: FLY, a
cosmological code for studying three-dimensional collisionless self-gravitating
systems with periodic boundary conditions; ATD, a parallel tree-code for the
simulation of the dynamics of boundary-free collisional and collisionless
self-gravitating systems and MARA, a code for stellar light curves analysis.
Other codes are going to be added to the portal.Comment: LaTeX with elsart.cls and harvard.sty (included). 7 pages. To be
submitted to a specific journa
Steps towards collective sustainability in biomedical research
The optimism surrounding multistakeholder research initiatives does not match the clear view of policies that are needed to exploit the potential of these collaborations. Here we propose some action items that stem from the integration between research advancements with the perspectives of patient-advocacy organizations, academia, and industry
Low-grade fibromyxoid sarcoma of the parapharyngeal space: A case report and review of the literature
This paper reports a rare case of Low-grade fibromyxoid sarcoma (LGFMS) that occurred primarily in the parapharyngeal space, in a 57-year-old woman. To the best of our knowledge, this is the first case of LGFMS arising from the parapharingeal space reported in the literature. Primary sarcomas of the head and neck region are very rare, accounting for approximately 1% of malignancies in this region. LGFMS is a distinctive type of soft-tissue sarcoma that was first described by Evans in 1987. LGFMS may be included in the differential diagnosis of tumors of the parapharyngeal space, and especially among the bland-looking spindle cell lesions. Despite its bland-looking morphology, this sarcoma should be recognized to avoid confusion with other bland-looking benign spindle cell lesions. Radical surgical resection with clear margins, is the treatment of choice of LGFMS. Despite its bland-looking histologic appearance, it is characterized by a malignant behavior with high rates of local recurrence and metastatic spread. For these reasones, all patients with LGFMS are recommended for long-term follow-up
The bicycle and the dream of a sustainable city: An explorative comparison of the image of bicycles in the mass-media and the general public
This paper explores the representation of the bicycle by comparing data from various mass media sources and the general public in Italy. In study 1, a number of commercial advertisements published on paper magazines and aired by the major TV channels, as well as 405 articles published by the major online newspapers were content analysed in order to identify the main concepts and evaluations characterising the representation of bikes in the media. In study 2, 94 Rome residents were interviewed on their beliefs regarding the pros and cons of using the bike in the city and their perceived social approval. Results showed several points of overlap between the two representations, although different themes and structures emerged as well
Evidence for Accretion in the High-resolution X-ray Spectrum of the T Tauri Star System Hen 3-600
We present high-resolution X-ray spectra of the multiple T Tauri star system
Hen 3-600, obtained with the High Energy Transmission Grating Spectrograph on
the Chandra X-ray Observatory. Two binary components were detected in the
zeroth-order image. Hen 3-600-A, which has a large mid-infrared excess, is a
2-3 times fainter in X-rays than Hen 3-600-B, due to a large flare on B. The
dispersed X-ray spectra of the two primary components overlap spatially;
spectral analysis was performed on the combined system. Analysis of the
individual spectra was limited to regions where the contributions of A and B
can be disentangled. This analysis results in two lines of evidence indicating
that the X-ray emission from Hen 3-600 is derived from accretion processes:
line ratios of O VII indicate that the characteristic density of its
X-ray-emitting plasma is large; a significant component of low-temperature
plasma is present and is stronger in component A. These results are consistent
with results obtained from X-ray gratings spectroscopy of more rapidly
accreting systems. All of the signatures of Hen 3-600 that are potential
diagnostics of accretion activity -- X-ray emission, UV excess, H-alpha
emission, and weak infrared excess -- suggest that its components represent a
transition phase between rapidly accreting, classical T Tauri stars and
non-accreting, weak-lined T Tauri stars.Comment: latex, 27 pages, 12 figures, 6 tables; accepted by Ap
Silicone-coated non-woven polyester dressing enhances reepithelialisation in a sheep model of dermal wounds
Negative-pressure wound therapy (NPWT) also known as V.A.C. (Vacuum-assisted closure), is widely used to manage various type of wounds and accelerate healing. NPWT has so far been delivered mainly via opencell polyurethane (PU) foam or medical gauze. In this study an experimental setup of sheep wound model was used to evaluate, under NPWT conditions, the performance of a silicone-coated non-woven polyester (N-WPE) compared with PU foam and cotton hydrophilic gauze, used as reference materials. Animals were anesthetized with spontaneous breathing to create three 3 9 3 cm skin defects bilaterally; each animal received three different samples on each side (n = 6 in each experimental group) and was subjected to negative and continuous 125 mmHg pressure up to 16 days. Wound conditions after 1, 8 and 16 days of treatment with the wound dressings were evaluated based on gross and histological appearances. Skin defects treated with the silicone-coated N-WPE showed a significant decrease in wound size, an increase of re-epithelialization, collagen deposition and wound neovascularisation, and a minimal stickiness to the wound tissue, in comparison with gauze and PU foam. Taken all together these findings indicate that the silicone-coated N-WPE dressing enhances wound healing since stimulates higher granulation tissue formation and causes minor tissue trauma during dressing changes
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