66 research outputs found

    Strong disorder renormalization group study of aperiodic quantum Ising chains

    Full text link
    We employ an adaptation of a strong-disorder renormalization-group technique in order to analyze the ferro-paramagnetic quantum phase transition of Ising chains with aperiodic but deterministic couplings under the action of a transverse field. In the presence of marginal or relevant geometric fluctuations induced by aperiodicity, for which the critical behavior is expected to depart from the Onsager universality class, we derive analytical and asymptotically exact expressions for various critical exponents (including the correlation-length and the magnetization exponents, which are not easily obtainable by other methods), and shed light onto the nature of the ground state structures in the neighborhood of the critical point. The main results obtained by this approach are confirmed by finite-size scaling analyses of numerical calculations based on the free-fermion method

    AÇÃO EDUCATIVA E CAPACITAÇÃO DOS CUIDADORES EM UMA INSTITUIÇÃO DE LONGA PERMANÊNCIA: UM RELATO DE EXPERIÊNCIA

    Get PDF
    Relato de experiência de graduandos da Faculdade de Medicina de Anápolis (UniEVANGÉLICA), na disciplina “Medicina de Família e Comunidade”. O objetivo do trabalho é relatar a ação educativa em uma Instituição de Longa Permanência (ILP) na cidade de Anápolis-GO, cujo cerne foi a capacitação de toda equipe da instituição, especialmente dos cuidadores dos idosos, realizada por acadêmicos de medicina. Utilizaram-se recursos dinâmicos, como discussão no formato “mesa redonda”, música e exploração do espaço físico, visando promover a sensibilização e a reflexão acerca do tema. Após a capacitação, realizou-se a aplicação das escalas da Avaliação Geriátrica Ampla (AGA) nos internos, objetivando avaliar o estado funcional, as condições médicas, o funcionamento social e a saúde mental (cognição e humor) dos idosos. Conclui-se que a vivência é uma importante construtora de conhecimento para os cuidadores, tanto formais quanto informais, sendo essenciais à formação de bons profissionais. Concluiu-se também, com os resultados da AGA, que grande parte dos internos da ILP possui alguma limitação, tendo destaque as síndromes demenciais que os impedem de realizar as Atividades de Vida Diárias (AVD’s) e Atividades Instrumentais de Vida Diárias (AIVD’s)

    Epidemiological profile of patients with skin cancer treated at the Regional Hospital of Asa Norte/DF - Brazil

    Get PDF
    Introduction: Skin cancer is the most common neoplasm in the Brazilian population, corresponding to 30% of all malignant tumors registered in the country. Non-melanoma malignant tumors are the type of cancer with the highest incidence and prevalence in Brazil. Basal cell carcinoma (BCC) is the most common, accounting for between 70% and 75% of cases. Squamous cell carcinoma (SCC) accounts for 20% of cases. The objective is to determine the epidemiological profile, the types and subtypes found in the histopathological results, the surgical conduct and its effectiveness in patients with a suspected malignant skin lesion. Methods: A retrospective descriptive study, based on the analysis of electronic medical records for resection of skin lesions suspected of malignancy, carried out by the Plastic Surgery team at the Regional Hospital of Asa Norte, Brasília/DF, from January 2012 to December 2016. Results: 533 patients were submitted to surgery, being female (51.6%), with a mean age of 68.97 years and 84% diagnosed with basal cell carcinoma with solid subtype. The compromised margins reached 11% of the sample. The most prevalent reconstructions were primary closure and local flaps. Conclusion: The epidemiological profile of patients treated with lesions suspected of skin cancer showed prevalence in women over 60 years with a history of sun exposure. The face was the most affected site, the nose being the most common topography. BCC is the most common type, and the circumscribed solid subtype was the most prevalent. The most used type of reconstruction was primary closure and local flap

    “Quem ensina também aprende” : a formação pela prática de professores primários na província do Paraná

    Full text link

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

    Get PDF
    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Clinical effectiveness and cost-effectiveness results from the randomised controlled Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea–hypopnoea (TOMADO) and long-term economic analysis of oral devices and continuous positive airway pressure

    Full text link

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

    Get PDF
    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Effects of aperiodicity on the quantum transitions in XY chains

    No full text
    Neste trabalho realizo uma adaptação do método de Ma, Dasgupta e Hu para o estudo e caracterização das transições de fase quânticas, induzidas por um campo transverso, em cadeias XY de spins 1/2, unidimensionais e aperiódicas, no espírito da adaptação correspondente para cadeias XXZ. O presente trabalho determina de forma analítica uma série de expoentes críticos associados às transições ferro-paramagnéticas do sistema, e dá pistas quanto à natureza das estruturas presentes no estado fundamental. Os resultados são então testados pelo emprego da técnica de férmions livres, da análise de nite size scaling e, no limite de Ising, de resultados extraídos do mapeamento do problema em uma caminhada aleatória.We employ an adaptation of the Ma, Dasgupta, Hu method in order to analyze the quantum phase transition, induced by a transversal magnetic eld, at spin-1/2 aperiodic XY chains, in analogy to the corresponding adaptation for XXZ chains. We derive analytical expressions for some cri tical exponents related with the ferro-paramagnetic transitions, and shed light onto the nature of the ground state structures. The main results obtained by this approach were tested by the free-fermion method, nite-size scaling analyses and, at the Ising limit of the model, by using results derived from a mapping to a random-walk problem
    corecore