1,642 research outputs found

    Representations of the cyclically symmetric q-deformed algebra soq(3)so_q(3)

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    An algebra homomorphism ψ\psi from the nonstandard q-deformed (cyclically symmetric) algebra Uq(so3)U_q(so_3) to the extension U^q(sl2){\hat U}_q(sl_2) of the Hopf algebra Uq(sl2)U_q(sl_2) is constructed. Not all irreducible representations of Uq(sl2)U_q(sl_2) can be extended to representations of U^q(sl2){\hat U}_q(sl_2). Composing the homomorphism ψ\psi with irreducible representations of U^q(sl2){\hat U}_q(sl_2) we obtain representations of Uq(so3)U_q(so_3). Not all of these representations of Uq(so3)U_q(so_3) are irreducible. Reducible representations of Uq(so3)U_q(so_3) are decomposed into irreducible components. In this way we obtain all irreducible representations of Uq(so3)U_q(so_3) when qq is not a root of unity. A part of these representations turns into irreducible representations of the Lie algebra so3_3 when q1q\to 1. Representations of the other part have no classical analogue. Using the homomorphism ψ\psi it is shown how to construct tensor products of finite dimensional representations of Uq(so3)U_q(so_3). Irreducible representations of Uq(so3)U_q(so_3) when qq is a root of unity are constructed. Part of them are obtained from irreducible representations of U^q(sl2){\hat U}_q(sl_2) by means of the homomorphism ψ\psi.Comment: 28 pages, LaTe

    The Barthel index: italian translation, adaptation and validation

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    The Barthel Index (BI) is widely used to measure disability also in Italy, although a validated and culturally adapted Italian version of BI has not been produced yet. This article describes the translation and cultural adaptation into Italian of the original 10-item version of BI, and reports the procedures for testing its validity and reliability. The cultural adaptation and validation process was based on data from a cohort of disabled patients from two different Rehabilitation Centers in Rome, Italy. Forward and backward translation method was adopted by qualified linguist and independent native English official translators. The scale obtained was reviewed by 20 experts in psychometric sciences. The Italian adapted version of the BI was then produced and validated. A total number of 180 patients were submitted to the adapted scale for testing its acceptability and internal consistency. The total time of compilation was 5 ± 2,6 minutes (range 3-10). Validation of the scale was performed by 7 trained professional therapists that submitted both the translated and the adapted versions to a group of 62 clinically stable patients (T-test=-2.051 p=0.05). The internal consistency by Cronbach’s alpha resulted equal to 0.96. Test – retest intra – rater reliability was evaluated on 35 cases; at test-retest was ICC=0.983 (95%IC: 0.967-0.992). This is the first study that reports translation, adaptation and validation of the BI in Italian language. It provides a new tool for professionals to measure functional disability when appraising Italian speaking disable patients in health and social care settings along the continuum of care

    Lagrangian versus Quantization

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    We discuss examples of systems which can be quantized consistently, although they do not admit a Lagrangian description.Comment: 8 pages, no figures; small corrections, references adde

    Further insights on predictors of environmental tobacco smoke exposure during the pediatric age

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    Background: The smoking ban in public places has reduced Environmental Tobacco Smoke (ETS) exposure for non-smokers, but despite this, domestic environments still remain places at high risk of exposure, and, today, about 40% of children worldwide are exposed to ETS at home. The aims of the study are to investigate the contribution of several factors on ETS exposure among a group of Italian children and to evaluate the changes in smoking precautions adopted at home when the smoker is the mother, the father, or both parents, respectively. Methods: A cross-sectional study was performed on a sample of 519 Italian schoolchildren. Information was collected via a questionnaire. Results: 41.4% of the participants lived with at least one smoker. Almost half of the children exposed to ETS lived with one or more smokers who do not observe any home smoking ban. Lower maternal or paternal educational levels significantly increase the risk of ETS exposure at home and the “worst case” is represented by both parents who smoke. Conclusions: More effective preventive interventions are needed to protect children from ETS exposure. Some interventions should be specifically dedicated to smokers with a low educational level and to mothers that smoke

    Invariant variational principle for Hamiltonian mechanics

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    It is shown that the action for Hamiltonian equations of motion can be brought into invariant symplectic form. In other words, it can be formulated directly in terms of the symplectic structure ω\omega without any need to choose some 1-form γ\gamma, such that ω=dγ\omega= d \gamma, which is not unique and does not even generally exist in a global sense.Comment: final version; to appear in J.Phys.A; 17 pages, 2 figure

    Versal deformations of a Dirac type differential operator

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    If we are given a smooth differential operator in the variable xR/2πZ,x\in {\mathbb R}/2\pi {\mathbb Z}, its normal form, as is well known, is the simplest form obtainable by means of the \mbox{Diff}(S^1)-group action on the space of all such operators. A versal deformation of this operator is a normal form for some parametric infinitesimal family including the operator. Our study is devoted to analysis of versal deformations of a Dirac type differential operator using the theory of induced \mbox{Diff}(S^1)-actions endowed with centrally extended Lie-Poisson brackets. After constructing a general expression for tranversal deformations of a Dirac type differential operator, we interpret it via the Lie-algebraic theory of induced \mbox{Diff}(S^1)-actions on a special Poisson manifold and determine its generic moment mapping. Using a Marsden-Weinstein reduction with respect to certain Casimir generated distributions, we describe a wide class of versally deformed Dirac type differential operators depending on complex parameters

    Appropriateness and efficacy of Spa therapy for musculoskeletal disorders. A Delphi method consensus initiative among experts in Italy.

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    OBJECTIVE: The aim of the study was to identify the main aspects concerning appropriateness and efficacy of Spa therapy for musculoskeletal pathologies. METHODS: A committee of 8 experts from Italian universities, public hospitals, territorial services, research institutes and patient associations was set up. Clinicians from Italian medical centers specialized in rheumatology, rehabilitation and thermal medicine took part in a Delphi process aimed at obtaining consensus statements among the participants. RESULTS: Large consensus was obtained for statements grouped under the following main themes: treatment indications; choice of treatment modality and treatment efficacy. CONCLUSIONS: The experts developed a number of consensus statements which may be used as a practical reference to guide the choice of physicians to treat musculoskeletal diseases with Spa therapy

    Polyphenon E enhances the antitumor immune response in neuroblastoma by inactivating myeloid suppressor cells

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    This is the author's accepted manuscript. The final published article is available from the link below. Note: In this manuscript as well as in the original published version of this article the word "Polyphenon" was incorrectly spelled in the title as "Polyphenol."Purpose: Neuroblastoma is a rare childhood cancer whose high risk, metastatic form has a dismal outcome in spite of aggressive therapeutic interventions. The toxicity of drug treatments is a major problem in this pediatric setting. In this study, we investigated whether Polyphenon E, a clinical grade mixture of green tea catechins under evaluation in multiple clinical cancer trials run by the National Cancer Institute (Bethesda, MD), has anticancer activity in mouse models of neuroblastoma. Experimental Design: We used three neuroblastoma models: (i) transgenic TH-MYCN mouse developing spontaneous neuroblastomas; (ii) nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice xenotransplanted with human SHSY5Y cells; and (iii) A/J mice transplanted with syngeneic Neuro 2A cells. Mice were randomized in control and Polyphenon E–drinking groups. Blood from patients with neuroblastoma and normal controls was used to assess the phenotype and function of myeloid cells. Results: Polyphenon E reduced the number of tumor-infiltrating myeloid cells, and inhibited the development of spontaneous neuroblastomas in TH-MYCN transgenic mice. In therapeutic models of neuroblastoma in A/J, but not in immunodeficient NOD/SCID mice, Polyphenon E inhibited tumor growth by acting on myeloid-derived suppressor cells (MDSC) and CD8 T cells. In vitro, Polyphenon E impaired the development and motility of MDSCs and promoted differentiation to more neutrophilic forms through the 67 kDa laminin receptor signaling and induction of granulocyte colony-stimulating factor. The proliferation of T cells infiltrating a patient metastasis was reactivated by Polyphenon E. Conclusions: These findings suggest that the neuroblastoma-promoting activity of MDSCs can be manipulated pharmacologically in vivo and that green tea catechins operate, at least in part, through this mechanism.SPARKS, Research in Childhood Cancer, the CGD Research Trust, and the Wellcome Trust
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