86 research outputs found

    Rigid upper bounds for the angular momentum and centre of mass of non-singular asymptotically anti-de Sitter space-times

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    We prove upper bounds on angular momentum and centre of mass in terms of the Hamiltonian mass and cosmological constant for non-singular asymptotically anti-de Sitter initial data sets satisfying the dominant energy condition. We work in all space-dimensions larger than or equal to three, and allow a large class of asymptotic backgrounds, with spherical and non-spherical conformal infinities; in the latter case, a spin-structure compatibility condition is imposed. We give a large class of non-trivial examples saturating the inequality. We analyse exhaustively the borderline case in space-time dimension four: for spherical cross-sections of Scri, equality together with completeness occurs only in anti-de Sitter space-time. On the other hand, in the toroidal case, regular non-trivial initial data sets saturating the bound exist.Comment: improvements in the presentation; some statements correcte

    Some Curvature Problems in Semi-Riemannian Geometry

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    In this survey article we review several results on the curvature of semi-Riemannian metrics which are motivated by the positive mass theorem. The main themes are estimates of the Riemann tensor of an asymptotically flat manifold and the construction of Lorentzian metrics which satisfy the dominant energy condition.Comment: 25 pages, LaTeX, 4 figure

    Padrões de crescimento no cavalo de desporto: aplicação de funções não-lineares

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    Apresentação oralO conhecimento das taxas de crescimento mais adequadas a cada raça e tipo de utilização é fundamental para criadores e utilizadores. O presente estudo teve como objetivo caracterizar os padrões de crescimento de cavalos de desporto, nascidos e criados numa coudelaria de referência, em França, utilizando funções não lineares. Para o efeito, 72 poldros (39 machos e 33 fêmeas) das raças Hanoveriana e Oldenburgo foram periodicamente pesados e medidos, tendo sido obtidos 1.382 registos para o peso vivo (PV) e altura ao garrote (AG). Os dados foram recolhidos entre o nascimento e os 5 anos de idade, quando os cavalos já estavam em trabalho regular. Inicialmente, foram ajustadas várias funções não-lineares (Brody, Logistic, Gompertz, von Bertalanffy e Richards) utilizando o procedimento NLIN do SAS. Contudo, a equação de Richards y = A(1 – b.exp(-kt))M foi escolhida para a análise posterior por se tratar do modelo que melhor se ajustou às duas variáveis. As taxas de crescimento (GMD, kg/d ou cm/d) foram obtidas a partir da primeira derivada das equações e o efeito do sexo foi também avaliado. O PV médio à idade adulta foi de 623,2±14,1 kg e a altura ao garrote 172,9±1,3 cm. Segundo os modelos obtidos, as proporções (%) do PV adulto aos 6, 12, 24, 36 e 48 meses de idade foram, respetivamente, 39, 55, 74, 84 e 90%. As proporções da AG para as mesmas idades foram 80, 87, 93, 96 e 98%. Não foi observado dimorfismo sexual para a AG. No entanto, os modelos relativos ao PV são diferentes entre poldros e poldras (P<0,0001). As taxas de crescimento obtidas são semelhantes às descritas noutras raças de desporto para um crescimento moderado. O estudo apresentado demonstra que a equação de Richards pode ser utilizada para descrever com precisão o crescimento e o desenvolvimento de cavalos de desporto.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio

    Co-Curriculum Implementation and Assessment in Accredited Doctor of Pharmacy Programs

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    Objective. To determine how accredited Doctor of Pharmacy programs implement and evaluate the co-curriculum requirement as mandated by the Accreditation Council for Pharmacy Education (ACPE). Methods. A survey was administered to all ACPE-accredited pharmacy programs to collect information regarding how co-curriculum models were being implemented, including types of activities, structure, learning outcomes, oversight, and assessment. The frequency of responses to items were presented to describe the general features of co-curriculum models. Results. The types of co-curricular activities reported by programs were generally consistent, with the majority of programs categorizing these activities and allowing students to choose which they would engage in. Most respondents reported that the program mapped co-curricular activities to learning outcomes, primarily ACPE Standards 1-4. The structural oversight of the co-curriculum typically included a co-curriculum committee, subcommittee, or task force, and supporting offices. The most common offices/departments involved in the co-curriculum were assessment, student affairs/services, experiential education, and academic/curricular affairs. The most common assessments were reflections, self-assessment surveys, and checklists. Conclusion. In most programs, implementation of the co-curriculum was a joint effort among various individuals, committees, and offices. Given the developing nature of programs, descriptive studies should be repeated to identify how programs develop and enhance co-curriculum models. The study results may be useful to members of the Academy when evaluating the current state of co-curriculum implementation and potential areas for program development

    Co-Curriculum Implementation and Assessment in Accredited Doctor of Pharmacy Programs

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    Objective. To determine how accredited Doctor of Pharmacy programs implement and evaluate the co-curriculum requirement as mandated by the Accreditation Council for Pharmacy Education (ACPE). Methods. A survey was administered to all ACPE-accredited pharmacy programs to collect information regarding how co-curriculum models were being implemented, including types of activities, structure, learning outcomes, oversight, and assessment. The frequency of responses to items were presented to describe the general features of co-curriculum models. Results. The types of co-curricular activities reported by programs were generally consistent, with the majority of programs categorizing these activities and allowing students to choose which they would engage in. Most respondents reported that the program mapped co-curricular activities to learning outcomes, primarily ACPE Standards 1-4. The structural oversight of the co-curriculum typically included a co-curriculum committee, subcommittee, or task force, and supporting offices. The most common offices/departments involved in the co-curriculum were assessment, student affairs/services, experiential education, and academic/curricular affairs. The most common assessments were reflections, self-assessment surveys, and checklists. Conclusion. In most programs, implementation of the co-curriculum was a joint effort among various individuals, committees, and offices. Given the developing nature of programs, descriptive studies should be repeated to identify how programs develop and enhance co-curriculum models. The study results may be useful to members of the Academy when evaluating the current state of co-curriculum implementation and potential areas for program development

    When Limb Surgery Has Become the Only Life-Saving Therapy in FOP: A Case Report and Systematic Review of the Literature

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    Fibrodysplasia ossificans progressiva (FOP) is a rare disease in which heterotopic ossification (HO) is formed in muscles, tendons and ligaments. Traumatic events, including surgery, are discouraged as this is known to trigger a flare-up with risk of subsequent HO. Anesthetic management for patients with FOP is challenging. Cervical spine fusion, ankylosis of the temporomandibular joints, thoracic insufficiency syndrome, restrictive chest wall disease, and sensitivity to oral trauma complicate airway management and anesthesia and pose life-threatening risks. We report a patient with FOP suffering from life-threatening antibiotic resistant bacterial infected ulcers of the right lower leg and foot. The anesthetic, surgical and postoperative challenges and considerations are discussed. In addition, the literature on limb surgeries of FOP patients is systemically reviewed. The 44 year-old female patient was scheduled for a through-knee amputation. Airway and pulmonary evaluation elicited severe abnormalities, rendering standard general anesthesia a rather complication-prone approach in this patient. Thus, regional anesthesia, supplemented with intravenous analgosedation and N2O-inhalation were performed in this case. The surgery itself was securely planned to avoid any unnecessary tissue damage. Postoperatively the patient was closely monitored for FOP activity by ultrasound and [18F]PET/CT-scan. One year after surgery, a non-significant amount of HO had formed at the operated site. The systematic review revealed seventeen articles in which thirty-two limb surgeries in FOP patients were described. HO reoccurrence was described in 90% of the cases. Clinical improvement due to improved mobility of the operated joint was noted in 16% of the cases. It should be noted, though, that follow-up time was limited and no or inadequate imaging modalities were used to follow-up in the majority of these cases. To conclude, if medically urgent, limb surgery in FOP is possible even when general anesthesia is not preferred. The procedure should be well-planned, alternative techniques or procedures should be tested prior to surgery and special attention should be paid to the correct positioning of the patient. According to the literature recurrent HO should be expected after surgery of a limb, even though it was limited in the case described
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