1,064 research outputs found

    Looking for a time independent Hamiltonian of a dynamical system

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    In this paper we introduce a method for finding a time independent Hamiltonian of a given dynamical system by canonoid transformation. We also find a condition that the system should satisfy to have an equivalent time independent formulation. We study the example of damped oscillator and give the new time independent Hamiltonian for it, which has the property of tending to the standard Hamiltonian of the harmonic oscillator as damping goes to zero.Comment: Some references added, LATEX fixing

    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

    The role of the occupational therapist in disaster areas: systematic review

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    Background. Disasters are increasingly more frequent events on our planet. During disaster the role of the occupational therapist will require a more specific operative framework within nongovernmental organizations and community health services. Design. Systematic review. Objective. The aim of this study is to evaluate the evidence that highlight occupational therapist’s role in disaster area through a systematic review. Materials and Methods. Research on MEDLINE was performed. All articles from 2005 to 2015 concerning rehabilitation and occupational therapy in disaster areas were included. Results. Ten studies were selected to be included in this review. Four interesting points emerged: the importance of having rehabilitation intervention in postdisaster situations, the necessity to include a rehabilitation team in the early phase of disaster response, the need to provide a method to address the difficult evacuation, and finding the safest method of transport of people with preexisting disabilities and new injuries. Conclusions. The amount of evidence with respect to specific intervention of the occupational therapist’s role in a disaster situation is limited. However some evidence suggests that it could be a good means for reducing the number of medical complications and deaths of persons with preexisting disabilities. The evidences found highlight the necessity to create a multidisciplinary team addressing needs in disasters situation, in which the occupational therapist could certainly contribute

    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

    CD40 ligand and MCP-1 as predictors of cardiovascular events in diabetic patients with stroke

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    Aim: Up-regulation of soluble CD40 ligand (sCD40L) and of monocyte chemoattractant protein-1 (MCP-1) has been found in diabetes and in patients with acute cerebral ischemia. We asked whether (i) the two molecules are similarly upregulated among non-lacunar and lacunar diabetic strokes and (ii) sCD40L and/or MCP-1 predict the risk of cardiovascular events in this setting.Methods: Ninety patients with type 2 diabetes mellitus presenting with an acute ischemic stroke (compared with 45 control subjects) were evaluated on admission and up to 36 months (median 24 months) after the event.Results: Diabetic patients with acute stroke had higher plasma CD40L and MCP-1 than controls (p<0.0001), with no significant differences among lacunar and non-lacunar strokes. On multiple regres-sion analysis, only higher sCD40L quartiles and older age were associated with higher MCP-1 quar-tiles. Forty-eight percent of patients experienced vascular events. Cox regression analysis showed that only the presence of higher sCD40L values independently predicted the recurrence of vascular events.Conclusion: Up-regulation of inflammatory molecules, such as CD40L and MCP-1, is involved in the advanced stage of atherosclerotic cerebro-vascular disease and is associated with increased risk of recurrence of cardiovascular events.AIM: Up-regulation of soluble CD40 ligand (sCD40L) and of monocyte chemoattractant protein-1 (MCP-1) has been found in diabetes and in patients with acute cerebral ischemia. We asked whether (i) the two molecules are similarly upregulated among non-lacunar and lacunar diabetic strokes and (ii) sCD40L and/or MCP-1 predict the risk of cardiovascular events in this setting. METHODS: Ninety patients with type 2 diabetes mellitus presenting with an acute ischemic stroke (compared with 45 control subjects) were evaluated on admission and up to 36 months (median 24 months) after the event. RESULTS: Diabetic patients with acute stroke had higher plasma CD40L and MCP-1 than controls (p<0.0001), with no significant differences among lacunar and non-lacunar strokes. On multiple regression analysis, only higher sCD40L quartiles and older age were associated with higher MCP-1 quartiles. Forty-eight percent of patients experienced vascular events. Cox regression analysis showed that only the presence of higher sCD40L values independently predicted the recurrence of vascular events. CONCLUSION: Up-regulation of inflammatory molecules, such as CD40L and MCP-1, is involved in the advanced stage of atherosclerotic cerebro-vascular disease and is associated with increased risk of recurrence of cardiovascular events

    Lentiviral Vector-Mediated Correction of a Mouse Model of Leukocyte Adhesion Deficiency Type I

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    Leukocyte adhesion deficiency type I (LAD-I) is a primary immunodeficiency caused by mutations in the ITGB2 gene and is characterized by recurrent and life-threatening bacterial infections. These mutations lead to defective or absent expression of β2 integrins on the leukocyte surface, compromising adhesion and extravasation at sites of infection. Three different lentiviral vectors (LVs) conferring ubiquitous or preferential expression of CD18 in myeloid cells were constructed and tested in human and mouse LAD-I cells. All three hCD18-LVs restored CD18 and CD11a membrane expression in LAD-I patient-derived lymphoblastoid cells. Corrected cells recovered the ability to aggregate and bind to sICAM-1 after stimulation. All vectors induced stable hCD18 expression in hematopoietic cells from mice with a hypomorphic Itgb2 mutation (CD18(HYP)), both in vitro and in vivo after transplantation of corrected cells into primary and secondary CD18(HYP) recipients. hCD18(+) hematopoietic cells from transplanted CD18(HYP) mice also showed restoration of mCD11a surface co-expression. The analysis of in vivo neutrophil migration in CD18(HYP) mice subjected to two different inflammation models demonstrated that the LV-mediated gene therapy completely restored neutrophil extravasation in response to inflammatory stimuli. Finally, these vectors were able to correct the phenotype of human myeloid cells derived from CD34(+) progenitors defective in ITGB2 expression. These results support for the first time the use of hCD18-LVs for the treatment of LAD-I patients in clinical trials

    The Moyal-Lie Theory of Phase Space Quantum Mechanics

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    A Lie algebraic approach to the unitary transformations in Weyl quantization is discussed. This approach, being formally equivalent to the \star-quantization, is an extension of the classical Poisson-Lie formalism which can be used as an efficient tool in the quantum phase space transformation theory.Comment: 15 pages, no figures, to appear in J. Phys. A (2001

    Longitudinal Analysis of Quality of Life, Clinical, Radiographic, Echocardiographic, and Laboratory Variables in Dogs with Preclinical Myxomatous Mitral Valve Disease Receiving Pimobendan or Placebo: The EPIC Study

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    Background: Changes in clinical variables associated with the administration of pimobendan to dogs with preclinical myxomatous mitral valve disease (MMVD) and cardiomegaly have not been described. Objectives: To investigate the effect of pimobendan on clinical variables and the relationship between a change in heart size and the time to congestive heart failure (CHF) or cardiac-related death (CRD) in dogs with MMVD and cardiomegaly. To determine whether pimobendan-treated dogs differ from dogs receiving placebo at onset of CHF. Animals: Three hundred and fifty-four dogs with MMVD and cardiomegaly. Materials and Methods: Prospective, blinded study with dogs randomized (ratio 1:1) to pimobendan (0.4-0.6 mg/kg/d) or placebo. Clinical, laboratory, and heart-size variables in both groups were measured and compared at different time points (day 35 and onset of CHF) and over the study duration. Relationships between short-term changes in echocardiographic variables and time to CHF or CRD were explored. Results: At day 35, heart size had reduced in the pimobendan group:median change in (Delta) LVIDDN -0.06 (IQR:-0.15 to + 0.02), P < 0.0001, and LA:Ao -0.08 (IQR:-0.23 to + 0.03), P < 0.0001. Reduction in heart size was associated with increased time to CHF or CRD. Hazard ratio for a 0.1 increase in Delta LVIDDN was 1.26, P = 0.0003. Hazard ratio for a 0.1 increase in Delta LA:Ao was 1.14, P = 0.0002. At onset of CHF, groups were similar. Conclusions and Clinical Importance: Pimobendan treatment reduces heart size. Reduced heart size is associated with improved outcome. At the onset of CHF, dogs treated with pimobendan were indistinguishable from those receiving placebo

    Analytic Controllability of Time-Dependent Quantum Control Systems

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    The question of controllability is investigated for a quantum control system in which the Hamiltonian operator components carry explicit time dependence which is not under the control of an external agent. We consider the general situation in which the state moves in an infinite-dimensional Hilbert space, a drift term is present, and the operators driving the state evolution may be unbounded. However, considerations are restricted by the assumption that there exists an analytic domain, dense in the state space, on which solutions of the controlled Schrodinger equation may be expressed globally in exponential form. The issue of controllability then naturally focuses on the ability to steer the quantum state on a finite-dimensional submanifold of the unit sphere in Hilbert space -- and thus on analytic controllability. A relatively straightforward strategy allows the extension of Lie-algebraic conditions for strong analytic controllability derived earlier for the simpler, time-independent system in which the drift Hamiltonian and the interaction Hamiltonia have no intrinsic time dependence. Enlarging the state space by one dimension corresponding to the time variable, we construct an augmented control system that can be treated as time-independent. Methods developed by Kunita can then be implemented to establish controllability conditions for the one-dimension-reduced system defined by the original time-dependent Schrodinger control problem. The applicability of the resulting theorem is illustrated with selected examples.Comment: 13 page

    La psichiatria di consultazione e collegamento nell’ospedale generale: l’esperienza perugina

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    Objective - This study describes the Consultation-Liaison Service of the Perugia University and investigates the significant associations between a many variables of the assessed population. Results - During the time from July 2008 to June 2009, 722 consultations were performed at the general hospital in Perugia. First examinations were 605. Most consultations involved European patients (95,2%) of female gender (56.3%); mean age was 55.77 (SD ± 21.27). Emergencies were 22.5%; one fifth of patients were not informed of having been referred to our service and half of interventions were requested by departments of internal medicine. The primary reasons for the referral were depression (18.6%), unexplained physical symptoms (12.3%) and anxiety (10.4%); most patients were already taking psychotropic medication before our intervention (58.8%).The significant associations are the following: associations between gender and social status (p < 0.01), social condition (p < 0.01), work (p < 0.01) and advice about the need of the consultation (p < 0.05). The area (medical, surgical and specialized area) are related with the advice (p < 0.05), the reason (p < 0.01) and the type of the consultation (p < 0.01), the diagnostic explanations (p < 0.01), the liaison investigations (p < 0.01) and, at last, with the longrange plan after discharge (p < 0.01)
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