A polarized atomic hydrogen beam

We describe the design and operating characteristics of a simple polarized atomic hydrogen beam particularly suitable for applications to crossed beams experiments. In addition to experimental measurements, we present the results of detailed computer models, using Monte-Carlo ray tracing techniques, optical analogs, and phase-space methods, that not only provide us with a confirmation of our measurement, but also allow us to characterize the density, polarization, and atomic fraction of the beam at all points along its path. As a subsidiary result, we also present measurements of the relative and absolute efficiencies of the V/G Supavac mass analyzer for masses 1 and 2

Envelhecimento e doenças neurodegenerativas crônicas na Amazônia brasileira: implantação de novas metodologias de avaliação em pacientes com declínio cognitivo leve e doença de Alzheimer

By 2025, the number of elderly people in the world will double and by 2050 will reach around two billion individuals, with the majority of them in developing countries. Alzheimer's disease (AD) is the fourth disease that most compromises the quality of life in elderly. This work aims to suggest new methodologies for evaluating elderly people with mild cognitive impairment and Alzheimer‟s disease, introducing a Brazilian version of the TSM-"Test Your Memory" and showing the performance fo this people in tests from CANTAB. It is an analytical, retrospective, longitudinal case-control study, performed at the Laboratory of Neurodegeneration and Infection, University Hospital João de Barros Barreto, from January 2009 to January 2011. Ninety five individuals 65 years old or older were divided in three groups: Alzheimer's disease (AD, n = 21), mild cognitive impairment (DCL, n = 31) and control (n = 43). Patients with previous stroke, primary depression, head injury, other dementias and other neuropsychiatric disorders, and serious visuo-auditory deficits were excluded. The participants were submitted to an initial assessment, screening with GDS-5 and DSM-IV, the International Physical Activity Questionnaire (IPAQ), CERAD neuropsychological test battery and the TSM - Test Your Memory (Brazilian version).Statistical analysis was performed using one-way ANOVA, defining the p-value<0.05 to detect significant differences. Female individuals of mixed ethnicity, aged 70 to 79 years predominated in all groups. The average MMSE score between the three groups was significantly different (control: 26.6± 2.2; DCL: 25.1 ± 2.6, DA: 17.3 ± 4.9, p <0.05), however, the TSM proved to be a more sensitive test to distinguish DCL patients from AD (control: 42.4± 5; DCL: 35.5 ± 7.7, DA: 25.7 ± 8, p <0.01 ). The three groups had different mean scores. In the CERAD word list, clock test, TNBr and phonological verbal fluency. The performance in TSM was significantly lower in DCL and AD groups than in the control group. And DA group was worse in this test than the DCL group too. The tests and measurements of CANTAB that best separate the three groups from the performance obtained were RVP A‟, PAL-trials to success and PAL-total errors in 6 patterns phase. Good correlations were found between the TSM and other tests, especially with the MMSE (Pearson‟s coefficient r = 0.79, p <0.0001) and clock test (r = 0.76, p <0.0001), as well as good correlations between the measures of PAL and TSM and MMSE. Physical activity level, in the control group was higher than in all other groups. When the level of physical activity and performance on cognitive tests were correlated, there were no significant differences in the different groups, except by a better performance in word recall test from CERAD, and word list in DCL group (DCL "active":4.7 ± 1.8; DCL"not active": 3 ± 1.5,p <0.01). Taken as a Whole, these results suggest that the application of automated automated neuropsychological tests associated with routine clinical tests and TYM, improve the clinical assessment´s sensitivity and reliability, especially in the early stages of dementia where the precoceous and accurate diagnosis are essential to guide therapeutic actions, drugs or behavioral modifications.Em 2025 o número de idosos no mundo irá dobrar e por volta de 2050 alcançará dois bilhões de indivíduos, estando a maioria em países desenvolvidos. A doença de Alzheimer (DA) é a quarta doença que mais compromete a qualidade de vida dos idosos. Este trabalho pretende sugerir novas metodologias de avaliação de pacientes com declínio cognitivo e doença de Alzheimer, apresentando uma versão brasileira a partir da versão original em língua inglesa intitulada “Test Your Memory” TYM (“teste sua memória- TSM), bem como mostrar os resultados do desempenho dos idosos na bateria de testes neuropsicológicos de Cambridge (CANTAB). Trata-se de estudo analítico, transversal retrospectivo do tipo caso-controle, realizado em pacientes do ambulatório de Geriatria do Hospital Universitário João de Barros Barreto, e em voluntários da comunidade no período de janeiro de 2009 a janeiro de 2011. Participaram 95 indivíduos com 65 ou mais anos de idade, divididos em 3 grupos: Alzheimer (DA, n=21), declínio cognitivo (DCL, n=31) e controle (n=43). Foram excluídos pacientes com história de acidente vascular encefálico (AVE), depressão primária, trauma cranioencefálico, outras demências, outras patologias neuropsiquiátricas e déficits visuo-auditivos limitantes. Os participantes foram submetidos à avaliação inicial, triagem com GDS-5 e DSM-IV, ao Questionário Internacional de Atividades Físicas (IPAQ), testes neuropsicológicos da bateria CERAD, teste do relógio, TSM (versão adaptada para o Português) e a bateria de Alzheimer do CANTAB. A análise estatística foi realizada empregando-se ANOVA, um critério, definindo-se o valor p<0,05 como significante. Houve predomínio em todos os grupos de indivíduos do gênero feminino, de cor parda, na faixa etária de 70 a 79 anos. A média de pontuação do MEEM entre os três grupos foi diferente (controle: 26,6±2,2; DCL: 25,1±2,6; DA: 17,3±4,9; p<0,05), entretanto o TSM mostrou ser uma ferramenta de triagem mais confiável para distinguir os pacientes DCL dos DA (controle: 42,4±5; DCL: 35,5±7,7; DA: 25,7±8; p<0,01). Na lista de palavras do CERAD, teste do relógio, TNBR e na fluência verbal fonológica os três grupos apresentaram diferenças significantes na média de pontos obtidos. A média da pontuação total no TSM foi significativamente menor nos grupos DCL e DA do que no grupo controle, e no grupo DA em relação ao DCL. Os testes e medidas do CANTAB que separam os três grupos pelo desempenho obtido são: RVP A‟, número de tentativas para o sucesso e total de erros na fase de 6 figuras do PAL. Foram encontradas boas correlações entre o TSM e outros testes, principalmente com o MEEM (Coeficiente de Pearson, r = 0,79; p<0,0001) e teste do relógio (r = 0,76; p<0,0001), bem como boa correlação entre as medidas do PAL e a pontuação do TSM e o MEEM. O nível de atividade física no grupo controle foi maior do que em todos os outros grupos. Ao ser correlacionado o nível de atividade física e o desempenho nos testes cognitivos, não foram observadas diferenças significativas nos diferentes grupos, exceto pela evocação de palavras no grupo DCL. Tomados em conjunto os resultados sugerem que a aplicação de testes neuropsicológicos automatizados associados aos testes da rotina clínica e ao TSM aumentam a resolução e a confiabilidade das análises particularmente no estágio inicial das síndromes demenciais onde a precocidade e a precisão diagnóstica são fundamentais para orientar as ações terapêuticas, sejam elas medicamentosas e/ou comportamentais

The association of cognitive and somatic depressive symptoms with depression recognition and outcomes after myocardial infarction

BACKGROUND: Among patients with acute myocardial infarction (AMI), depression is both common and under-recognized. The association of different manifestations of depression, somatic and cognitive, with depression recognition and long-term prognosis is poorly understood. METHODS AND RESULTS: Depression was confirmed in 481 AMI patients enrolled from 21 sites during their index hospitalization with a Patient Health Questionnaire (PHQ-9) score ≥10. Within the PHQ-9, separate somatic and cognitive symptom scores were derived and the independent association between these domains and the clinical recognition of depression, as documented in the medical records, was evaluated. In a separate multisite AMI registry of 2,347 patients, the association between somatic and cognitive depressive symptoms and 4-year all-cause mortality and 1-year all-cause rehospitalization was evaluated. Depression was clinically recognized in 29% (n=140) of patients. Cognitive depressive symptoms (Relative Risk [RR] per Standard Deviation [SD] increase=1.14; 95% confidence interval [CI] 1.03–1.26; p=0.01) were independently associated with depression recognition, while the association for somatic symptoms and recognition (RR=1.04; 95% CI 0.87–1.26; p=0.66) was not significant. However, unadjusted Cox regression analyses found that only somatic depressive symptoms were associated with 4-year mortality (Hazard Ratio [HR] per SD increase=1.22; 95% confidence interval [CI] 1.08–1.39) or 1-year rehospitalization (HR=1.22; 95%CI 1.11–1.33) while cognitive manifestations were not (HR for mortality=1.01; 95%CI 0.89–1.14; HR for rehospitalization=1.01; 95%CI 0.93–1.11). After multivariable adjustment, the association between somatic symptoms and rehospitalization persisted (HR=1.16; 95% CI:1.06–1.27; p=0.01) but was attenuated for mortality (HR=1.07; 95% CI:0.94–1.21; p=0.30). CONCLUSIONS: Depression after AMI was recognized in fewer than 1 in 3 patients. Although cognitive symptoms were associated with recognition of depression, somatic symptoms were associated with long-term outcomes. Comprehensive screening and treatment of both somatic and cognitive symptoms may be necessary to optimize depression recognition and treatment in AMI patients

Multiaxial Kitagawa analysis of A356-T6

Experimental Kitagawa analysis has been performed on A356-T6 containing natural and artificial defects. Results are obtained with a load ratio of R = -1 for three different loadings: tension, torsion and combined tension-torsion. The critical defect size determined is 400 \pm 100 \mum in A356-T6 under multiaxial loading. Below this value, the microstructure governs the endurance limit mainly through Secondary Dendrite Arm Spacing (SDAS). Four theoretical approaches are used to simulate the endurance limit characterized by a Kitagawa relationship are compared: Murakami relationships [Y Murakami, Metal Fatigue: Effects of Small Defects and Nonmetallic Inclusions, Elsevier, 2002.], defect-crack equivalency via Linear Elastic Fracture Mechanics (LEFM), the Critical Distance Method (CDM) proposed by Susmel and Taylor [L. Susmel, D. Taylor. Eng. Fract. Mech. 75 (2008) 15.] and the gradient approach proposed by Nadot [Y. Nadot, T. ~Billaudeau. Eng. Fract. Mech. 73 (2006) 1.]. It is shown that the CDM and gradient methods are accurate; however fatigue data for three loading conditions is necessary to allow accurate identification of an endurance limit.Comment: 27 pages, 11 figure

Viral Retinitis following Intraocular or Periocular Corticosteroid Administration: A Case Series and Comprehensive Review of the Literature.

Abstract Purpose: To describe viral retinitis following intravitreal and periocular corticosteroid administration. Methods: Retrospective case series and comprehensive literature review. Results: We analyzed 5 unreported and 25 previously published cases of viral retinitis following local corticosteroid administration. Causes of retinitis included 23 CMV (76.7%), 5 HSV (16.7%), and 1 each VZV and unspecified (3.3%). Two of 22 tested patients (9.1%) were HIV positive. Twenty-one of 30 (70.0%) cases followed one or more intravitreal injections of triamcinolone acetonide (TA), 4 (13.3%) after one or more posterior sub-Tenon injections of TA, 3 (10.0%) after placement of a 0.59-mg fluocinolone acetonide implant (Retisert), and 1 (3.3%) each after an anterior subconjunctival injection of TA (together with IVTA), an anterior chamber injection, and an anterior sub-Tenon injection. Mean time from most recent corticosteroid administration to development of retinitis was 4.2 months (median 3.8; range 0.25-13.0). Twelve patients (40.0%) had type II diabetes mellitus. Treatments used included systemic antiviral agents (26/30, 86.7%), intravitreal antiviral injections (20/30, 66.7%), and ganciclovir intravitreal implants (4/30, 13.3%). Conclusions: Viral retinitis may develop or reactivate following intraocular or periocular corticosteroid administration. Average time to development of retinitis was 4 months, and CMV was the most frequently observed agent. Diabetes was a frequent co-morbidity and several patients with uveitis who developed retinitis were also receiving systemic immunosuppressive therapy

Dynamics of spin-2 Bose condensate driven by external magnetic fields

Dynamic response of the F=2 spinor Bose-Einstein condensate (BEC) under the influence of external magnetic fields is studied. A general formula is given for the oscillation period to describe population transfer from the initial polar state to other spin states. We show that when the frequency and the reduced amplitude of the longitudinal magnetic field are related in a specific manner, the population of the initial spin-0 state will be dynamically localized during time evolution. The effects of external noise and nonlinear spin exchange interaction on the dynamics of the spinor BEC are studied. We show that while the external noise may eventually destroy the Rabi oscillations and dynamic spin localization, these coherent phenomena are robust against the nonlinear atomic interaction.Comment: 16 pages, 7 figures. accepted by Phys. Rev.

Quantum Entanglement of Excitons in Coupled Quantum Dots

Optically-controlled exciton dynamics in coupled quantum dots is studied. We show that the maximally entangled Bell states and Greenberger-Horne-Zeilinger (GHZ) states can be robustly generated by manipulating the system parameters to be at the avoided crossings in the eigenenergy spectrum. The analysis of population transfer is systematically carried out using a dressed-state picture. In addition to the quantum dot configuration that have been discussed by Quiroga and Johnson [Phys. Rev. Lett. \QTR{bf}{83}, 2270 (1999)], we show that the GHZ states also may be produced in a ray of three quantum dots with a shorter generation time.Comment: 16 pages, 7 figures, to appear in Phys. Rev.

Scalar Synchrotron Radiation in the Schwarzschild-anti-de Sitter Geometry

We present a complete relativistic analysis for the scalar radiation emitted by a particle in circular orbit around a Schwarzschild-anti-de Sitter black hole. If the black hole is large, then the radiation is concentrated in narrow angles- high multipolar distribution- i.e., the radiation is synchrotronic. However, small black holes exhibit a totally different behavior: in the small black hole regime, the radiation is concentrated in low multipoles. There is a transition mass at $M=0.427 R$, where $R$ is the AdS radius. This behavior is new, it is not present in asymptotically flat spacetimes.Comment: 13 pages, 6 figures, published version. References adde

Testing SUSY

If SUSY provides a solution to the hierarchy problem then supersymmetric states should not be too heavy. This requirement is quantified by a fine tuning measure that provides a quantitative test of SUSY as a solution to the hierarchy problem. The measure is useful in correlating the impact of the various experimental measurements relevant to the search for supersymmetry and also in identifying the most sensitive measurements for testing SUSY. In this paper we apply the measure to the CMSSM, computing it to two-loop order and taking account of current experimental limits and the constraint on dark matter abundance. Using this we determine the present limits on the CMSSM parameter space and identify the measurements at the LHC that are most significant in covering the remaining parameter space. Without imposing the LEP Higgs mass bound we show that the smallest fine tuning (1:13) consistent with a relic density within the WMAP bound corresponds to a Higgs mass of 114$\pm$2 GeV. Fine tuning rises rapidly for heavier Higgs.Comment: 12 pages, 7 figures; references added, figures updated for extended parameter space sca