Bremsstrahlung in Alpha-Decay

We present the first fully quantum mechanical calculation of photon radiation accompanying charged particle decay from a barrier resonance. The soft-photon limit agrees with the classical results, but differences appear at next-to-leading-order. Under the conditions of alpha-decay of heavy nuclei, the main contribution to the photon emission stems from Coulomb acceleration and may be computed analytically. We find only a small contribution from the tunneling wave function under the barrier.Comment: 12 pages, 2 Postscript figure

Reflection of light from a disordered medium backed by a phase-conjugating mirror

This is a theoretical study of the interplay of optical phase-conjugation and multiple scattering. We calculate the intensity of light reflected by a phase-conjugating mirror when it is placed behind a disordered medium. We compare the results of a fully phase-coherent theory with those from the theory of radiative transfer. Both methods are equivalent if the dwell time \tau_{dwell} of a photon in the disordered medium is much larger than the inverse of the frequency shift 2\Delta\omega acquired at the phase-conjugating mirror. When \tau_{dwell} \Delta\omega < 1, in contrast, phase coherence drastically affects the reflected intensity. In particular, a minimum in the dependence of the reflectance on the disorder strength disappears when \Delta\omega is reduced below 1/\tau_{dwell}. The analogies and differences with Andreev reflection of electrons at the interface between a normal metal and a superconductor are discussed.Comment: 27 pages RevTeX with 11 figures included with psfi

Influence of personalized extended interval dosing on the natalizumab wearing-off effect - a sub-study of the NEXT-MS trial

Background and objectives: Wearing-off symptoms during natalizumab treatment in multiple sclerosis are characterized by an increase of MS-related symptoms prior to natalizumab administration. The influence of extended interval dosing (EID) on wearing-off symptoms are important to consider, as this might cause hesitancy in initiating or continuing EID. Methods: Participants of the NEXT-MS trial, in which treatment intervals are adjusted based on drug concentrations, were divided into two groups: an extended group containing participants with at least one week of additional interval extension, and a group with a fixed interval during the trial (range 4–7 weeks). Changes in the occurrence, frequency, onset, and severity of wearing-off symptoms were evaluated. Results: 255 participants were included (extended group n = 171, fixed group n = 84). The odds on occurrence of wearing-off symptoms in the extended group did not increase after extending the treatment interval. Additional analyses for frequency, onset, and severity of wearing-off symptoms showed no changes over time. Mean decrease in natalizumab drug concentration did not influence the frequency of wearing-off symptoms. Discussion: Wearing-off symptoms were not reinforced by further extending the natalizumab interval. Wearing-off symptoms might increase in a minority of patients after EID, although our data support the view that wearing-off symptoms appear to be unrelated to the decrease in natalizumab trough drug concentrations.</p

Self-reported work productivity in people with multiple sclerosis and its association with mental and physical health

PURPOSE: This study aimed to identify mental health, physical health, demographic and disease characteristics relating to work productivity in people with multiple sclerosis (MS). METHODS: In this cross-sectional study, 236 employed people with MS (median age = 42 years, 78.8% female) underwent neurological and neuropsychological assessments. Additionally, they completed questionnaires inquiring about work productivity (presenteeism: reduced productivity while working, and absenteeism: loss of productivity due to absence from work), mental and physical health, demographic and disease characteristics. Multiple linear and logistic regression analyses were performed with presenteeism and absenteeism as dependent variables, respectively. RESULTS: A model with mental and physical health factors significantly predicted presenteeism F(11,202) = 11.33, p < 0.001, R2 = 0.38; a higher cognitive (p < 0.001) and physical impact (p = 0.042) of fatigue were associated with more presenteeism. A model with only mental health factors significantly predicted absenteeism; χ2(11)=37.72, p < 0.001, with R2 = 0.27 (Nagelkerke) and R2 = 0.16 (Cox and Snell). Specifically, we observed that more symptoms of depression (p = 0.041) and a higher cognitive impact of fatigue (p = 0.011) were significantly associated with more absenteeism. CONCLUSIONS: In people with MS, both cognitive and physical impact of fatigue are positively related to presenteeism, while symptoms of depression and cognitive impact of fatigue are positively related to absenteeism.Implications for rehabilitationMultiple sclerosis (MS) affects people of working age, significantly interfering with work productivity.Higher cognitive and physical impact of fatigue were associated with more presenteeism in workers with MS.A higher cognitive impact of fatigue and more depressive symptoms were associated with absenteeism in workers with MS.Occupational and healthcare professionals should be aware of the impact of both physical and mental health on work productivity in workers with MS

Proliferation and aneusomy predict survival of young patients with astrocytoma grade II

The clinical course of astrocytoma grade II (AII) is highly variable and not reflected by histological characteristics. As one of the best prognostic factors, higher age identifies rapid progressive A II. For patients over 35 years of age, an aggressive treatment is normally propagated. For patients under 35 years, there is no clear guidance for treatment choices, and therefore also the necessity of histopathological diagnosis is often questioned. We studied the additional prognostic value of the proliferation index and the detection of genetic aberrations for patients with A II. The tumour samples were obtained by stereotactic biopsy or tumour resection and divided into two age groups, that is 18–34 years (n=19) and 35 years (n=28). Factors tested included the proliferation (Ki-67) index, and numerical aberrations for chromosomes 1, 7, and 10, as detected by in situ hybridisation (ISH). The results show that age is a prognostic indicator when studied in the total patient group, with patients above 35 years showing a relatively poor prognosis. Increased proliferation index in the presence of aneusomy appears to identify a subgroup of patients with poor prognosis more accurately than predicted by proliferation index alone. We conclude that histologically classified cases of A II comprise a heterogeneous group of tumours with different biological and genetic constitution, which exhibit a highly variable clinical course. Immunostaining for Ki-67 in combination with the detection of aneusomy by ISH allows the identification of a subgroup of patients with rapidly progressive A II. This is an extra argument not to defer stereotactic biopsy in young patients with radiological suspicion of A II

Aplicação de deficientes físicos nas atividades da Polícia Militar do Paraná

Orientador: Ivan Santa MariaMonografia (Especialização) - Universidade Federal do Paraná,Setor de Ciências Sociais Aplicadas, Departamento de Contabilidade, Curso de Especialização em Administração PolicialResumo: O presente trabalho monográfico abordou o problema da aplicabilidade de policiais-militares em atividades consideradas meio na Organização, sendo que os mesmos poderiam ser substituídos por deficientes físicos em algumas funções básicas, como telefonista, recepcionista, digitador e outros, redundando num maior emprego de policiaismilitares nas ruas. Para tanto, buscou primeiramente retratar a realidade na PMPR; caracterizar atividades de cunho civil e de cunho militar na atividade meio; além de onde e como aplicar a pessoa portadora de deficiência física. Na parte do desenvolvimento, foram abordadas conceituações básicas, como atividade Policial Militar, atividades-meio e atividades-fim da Polícia Militar, cunho civil e militar na atividade-meio. Na seqüência, abordaram-se aspectos da pessoa portadora de deficiência, sendo navegado em assuntos a respeito da antigüidade, do renascimento, a política demográfica, deficiência em si, Programa Nacional de Direitos Humanos, a realidade social do deficiente e sua situação atual. Tratou-se também dos deficientes físicos e a Polícia Militar, em que buscou-se evidenciar o que existe em legislação peculiar e cargos privativos de militares. Quanto aos direitos dos deficientes, relatou-se a respeito dos tratados internacionais e a legislação brasileira. Ainda no capítulo referente ao desenvolvimento retratou-se a respeito do PSAV - Prestador de Serviço Auxiliar Voluntário (Deficientes Físicos); APR - Associação Paranaense de Reabilitação; ADFP -Associação dos Deficientes Físicos do Paraná; empresas que abrem caminhos para deficientes; uma importante matéria veiculada na Gazeta do Povo com o título "700 Deficientes podem Perder o Emprego", postura esta defendida pelo Estado como sendo o serviço prestado de grande importância econômica e social. Um capítulo tratou sobre a presença de pessoal civil na Polícia Militar, com seus fundamentos legais e doutrinários. Chegou-se ao final do desenvolvimento retratando como seria uma possível implantação da alocação de deficientes físicos em certas atividades-meio da Polícia Militar do Paraná Finalizou o presente estudo tratando das considerações finais, em que algumas propostas foram colocadas, ressaltando-se a importância de primeiramente serem readequadas as instalações físicas das Unidades Policiais-Militares para o ideal recebimento destes funcionário

Products of cells from gliomas: IX. Evidence that two fundamentally different mechanisms change extracellular matrix expression by gliomas

Four human astrocytic gliomas of high grade of malignancy were each evaluated in tissue and in vitro for percentages of cells expressing glial fibrillary acidic protein (GFAP), collagen type IV, laminin and fibronectin assessed by immunofluorescence with counterstaining of nuclear DNA. Percentages of cells with reticulin and cells binding fluorescein-labeled Ulex europaeus agglutinin were also assessed. In tissue, each extracellular matrix (ECM) component was associated with cells in the walls of abnormal proliferations of glioma vessels, and all four tumors had the same staining pattern. Two strikingly different patterns of conversion of gene product expression emerged during in vitro cultivation. (1). In the most common pattern, percentages of all six markers consistently shifted toward the exact phenotype of mesenchymal cells in abnormal vascular proliferations: increased reticulin, collagen type IV, laminin and fibronectin; markedly decreased glial marker GFAP and absent endothelial marker Ulex europaeus agglutinin. The simplest explanation of this constellation of changes coordinated toward expression of vascular ECM markers is that primary glioma cell cultures are overgrown by mesenchymal cells from the abnormal vascular proliferations of the original glioma. These cell cultures were tested for in situ hybridization (ISH) signals of chromosomes 7 and 10. Cells from one glioma had diploid signals. Cells from the other glioma had aneuploid signals indicating they were neoplastic; however, their signals reflected different numerical chromosomal aberrations than those common to neoplastic glia. (2). The second pattern was different. Cells with ISH chromosomal signals of neoplastic glia retained GFAP, and gained collagen type IV. Their laminin and fibronectin diminished, but persisted among a lower percentage of cells. Cloning and double immunofluorescence confirmed the presence of individual cells with glial and mesenchymal markers. A cell expressing GFAP in addition to either fibronectin, reticulin or collagen type IV is not a known constituent of glioblastoma tissue. This provides evidence of a second mechanism of conversion of gene expression in gliomas.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45382/1/11060_2005_Article_BF01052843.pd

Clinical involvement and transparency in medical apps: reply to O'Neill and Brady

I congratulate the authors of "Colorectal smartphone apps: opportunities and risks" on their highly topical review of the medical professional involvement in the design and content of medical apps in the field of colorectal disease (1). The author states that there is little medical professional involvement in colorectal apps design and increased regulation is required to improve accountability of app content. This assumes that it is essential for clinical experts to be involved in the development of medical apps for them to be reliable, accurate, evidence-based and safe. © 2012 The Authors Colorectal Disease © 2012 The Association of Coloproctology of Great Britain and Irelan