Channel estimation in massive MIMO systems

Last years were characterized by a great demand for high data throughput, good quality and spectral efficiency in wireless communication systems. Consequently, a revolution in cellular networks has been set in motion towards to 5G. Massive multiple-input multiple-output (MIMO) is one of the new concepts in 5G and the idea is to scale up the known MIMO systems in unprecedented proportions, by deploying hundreds of antennas at base stations. Although, perfect channel knowledge is crucial in these systems for user and data stream separation in order to cancel interference. The most common way to estimate the channel is based on pilots. However, problems such as interference and pilot contamination (PC) can arise due to the multiplicity of channels in the wireless link. Therefore, it is crucial to define techniques for channel estimation that together with pilot contamination mitigation allow best system performance and at same time low complexity. This work introduces a low-complexity channel estimation technique based on Zadoff-Chu training sequences. In addition, different approaches were studied towards pilot contamination mitigation and low complexity schemes, with resort to iterative channel estimation methods, semi-blind subspace tracking techniques and matrix inversion substitutes. System performance simulations were performed for the several proposed techniques in order to identify the best tradeoff between complexity, spectral efficiency and system performance

Nd:YAG laser scribed zinc oxide on semi-flexible copper foils

In this work, a novel approach to synthesise zinc oxide (ZnO) directly on flexible copper substrates is proposed. The produced samples show a foam-like morphology made of agglomerates of small ZnO particles when processed at laser energy density of 18.0 J/cm2. On the other hand, the samples processed at higher beam energy density, i.e. 33.2 J/cm2, resulted in a more granular morphology, with some ZnO particles dispersed over the sample’s surface. Raman spectroscopy measurements demonstrated that this method resulted in the formation of wurtzite-ZnO crystalline phase in all samples. Room temperature photoluminescence spectroscopy analysis revealed the presence of a broad visible band in the orange-red region dominating the spectra, with a small contribution from the near band edge emission in the UV spectral region. Decreasing the beam energy fluence from 33.2 to 18.0 J/cm2 resulted in samples with higher overall visible band intensity, in line with what was observed for their crystalline quality. Moreover, the shift of the broad band maxima towards longer wavelengths could be an indication of the possibility of tuning the visible emission according to the chosen laser processing conditions.publishe

Perceptions of patients, physicians, and medical students on physicians’ appearance*

AbstractObjectiveTo investigate the impressions made by different styles of dress and appearance adopted by physicians on patients, medical students, and other physicians in Brazil.MethodsTwo hundred fifty nine patients, 119 students, and 99 physicians answered questions related to a panel of male and female physicians’ pictures covering the following styles: white clothing; white coat; formal coat; formal, informal, and casual garments; and surgical scrubs. They also reported their level of discomfort with a list of 20 items for professional appearance of both genders.ResultsMost of the answers of the volunteers involved using white clothes or white coat, and in many situations the percentages of preference referred for these styles were close. Physicians and students preferred physicians wearing surgical scrubs for emergency visits, and doctors with informal style for discussing psychological problems with male professionals. Patients most often chose white clothing in response to questions. Regarding male professionals, all three groups reported a high degree of discomfort for the use of shorts and bermuda shorts, multiple rings, facial piercings, sandals, extravagant hair color, long hair, and earrings. For females, high levels of discomfort were reported for shorts, blouses exposing the belly, facial piercings, multiple rings, extravagant hair color, and heavy makeup.ConclusionBrazilian patients, physicians, and medical students form a better initial impression of physicians using clothing traditionally associated with the profession and exhibiting a more conventional appearance. The use of entirely white garments appears to be a satisfactory option in this country

Impressões de pacientes, médicos e estudantes de Medicina quanto a aparência dos médicos

ResumoObjetivoInvestigar as impressões causadas em pacientes, estudantes de Medicina e médicos brasileiros por diferentes estilos de vestimenta e aparência adotados pelos médicos.MétodosParticiparam da pesquisa 259 pacientes, 119 estudantes e 99 médicos, respondendo questões relativas a um painel de fotos de médico e médica vestidos nos seguintes estilos: roupa branca, avental branco, avental social, formal, informal, casual e centro cirúrgico. Eles ainda registraram seu grau de desconforto frente uma lista de 20 itens de aparência para profissionais de ambos os sexos.ResultadoA maioria das respostas dos voluntários envolveu o uso de roupa branca ou avental branco, e em muitas questões os percentuais de preferência referidos para esses estilos foram muito próximos. Médicos e estudantes preferiram profissionais em traje de centro cirúrgico para consultas de urgência, e o estilo informal para discutir problemas psicológicos com profissional masculino. Os pacientes escolheram mais frequentemente a roupa branca em resposta às questões. No tocante aos profissionais masculinos, os três grupos referiram elevado grau de incômodo para o uso de shorts e bermudas, muitos anéis, piercing facial, sandálias, cabelos de cor extravagante, cabelos compridos e brincos. Para o sexo feminino, níveis elevados de desconforto foram assinalados para shorts, blusas mostrando a barriga, piercing facial, bermudas, muitos anéis, cabelos de cor extravagante e maquiagem carregada.ConclusãoPacientes, médicos e estudantes de Medicina brasileiros desenvolvem melhor impressão inicial de médicos que utilizam trajes tradicionalmente associados com a profissão e de aparência mais convencional. O uso da vestimenta inteiramente branca parece ser opção satisfatória no Brasil.AbstractObjectiveTo investigate the impressions made by different styles of dress and appearance adopted by physicians on patients, medical students and other physicians in Brazil.MethodsTwo hundred fifty nine patients, 119 students, and 99 physicians answered questions related to a panel of male and female physicians’ pictures covering the following styles: white clothing; white coat; formal, informal, and casual garments; and surgical scrubs. They also reported their level of discomfort with a list of 20 items for professional appearance of both genders.ResultsMost of the answers of the volunteers involved using white clothes or white coat, and in many situations the percentages of preference referred for these styles were close. Physicians and students preferred physicians wearing surgical scrubs for emergency visits, and doctors with informal style for discussing psychological problems with male professionals. Patients most often chose white clothing in response to questions. Regarding male professionals, all three groups reported high degree of discomfort for the use of shorts and bermuda shorts, multiple rings, facial piercing, sandals, extravagant hair color, long hair, and earrings. For females, high levels of discomfort were reported to shorts, blouses exposing the belly, facial piercing, multiple rings, extravagant hair color, and heavy makeup.ConclusionBrazilian patients, physicians, and medical students form a better initial impression of physicians using clothing traditionally associated with the profession and exhibiting more conventional appearance. The use of entirely white garments appears to be a satisfactory option in this country

Chronic Urticaria in the Real-Life Clinical Practice Setting in Portugal: Baseline Results from the Non-Interventional Multicentre AWARE Study

Introduction: There is a paucity of information regarding chronic urticaria patients’ care in a real-world setting. The objective of this study was to report and evaluate the baseline characteristics of Portuguese chronic urticaria patients refractory to H1-antihistamines included in the AWARE study. Material and Methods: This is a non-interventional cohort study. Adult patients with a diagnosis of chronic urticaria with symptoms for at least two months, refractory to H1-antihistamines, consulting one of the 10 participating urticaria centers throughout Portugal have been included in the study. Baseline sociodemographic data, medical history, clinical parameters, medication, weekly urticaria activity score, and dermatology quality of life index have been collected. Results: Seventy six patients were included, of which 76.3% were women. The majority of patients had a diagnosis of chronic spontaneous urticaria (88.2%) and 39.5% had angioedema. Around 91.0% of patients were medicated with non-sedative H1-antihistamines and 35.4% with a third line therapy. Median dermatology quality of life index was 5.0 and median weekly urticaria activity score was 13.0. Discussion: The baseline results suggest that patients with chronic urticaria refractory to H1-antihistamines are being under-treated in the real-world setting. Conclusion: The AWARE study demonstrates the real impact of chronic urticaria on Portuguese patients refractory to H1-antihistamines treatment, and 30% report a very large or extremely large deleterious effect on their quality of life. The follow-up of these patients will allow evaluating strategies aimed at optimizing disease control

A PRÁTICA DO ACOLHIMENTO NA ESTRATÉGIA SAÚDE DA FAMÍLIA

To analyze the practice of reception in the family health strategy using scientific evidence. Methods: This is a qualitative integrative literature review. The search for works involved in the research was carried out in the following databases: SCIELO, LILACS, BDENF and MEDLINE, using the descriptors in health sciences: "Welcoming", "Family health strategy" and "Humanization of care". The inclusion criteria were: published between 2014 and 2024, with free access to full texts, articles in Portuguese, English and Spanish and related to the theme. Exclusion criteria were: duplicate articles, incomplete articles, abstracts, reviews, debates, articles published in event proceedings and unavailable in full. Results: The practice of welcoming patients goes beyond qualified listening; this method of care is capable of identifying problems and promoting resolutive interventions. Conclusion: It can be concluded that welcoming is an important tool in the primary care process, since it is responsible for establishing a bond between members of the health team and users.Analisar por meio das evidências cientificas a prática do acolhimento na estratégia saúde da família. Métodos: Trata-se de uma revisão integrativa da literatura de caráter qualitativo. A busca dos trabalhos envolvidos na pesquisa foi realizada nas seguintes bases de dados: SCIELO, LILACS, BDENF e MEDLINE, a partir dos descritores em ciências da saúde: “Acolhimento”, “Estratégia saúde da família” e “Humanização da assistência”. Os critérios de inclusão foram: publicados no período entre 2014 e 2024, cujo acesso ao periódico era livre aos textos completos, artigos em idioma português, inglês e espanhol e relacionados a temática. Critérios de exclusão foram: artigos duplicados, incompletos, resumos, resenhas, debates, artigos publicados em anais de eventos e indisponíveis na íntegra. Resultados: A prática da realização do acolhimento vai além da escuta qualificada esse método de cuidado é capaz de identificar problemas e promover intervenções resolutivas. Conclusão: Conclui-se que o acolhimento é uma ferramenta importante no processo de cuidado na atenção primária, visto que, ele é responsável pelo estabelecimento de vínculo entre os membros da equipe de saúde e os usuários

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

AVALIAÇÃO DO CONFORTO HUMANO DE PISOS MISTOS (AÇOCONCRETO) DE EDIFICAÇÕES COM BASE NO EMPREGO DE MODELOS BIODINÂMICOS

O objetivo deste trabalho é propor uma metodologia para análise dinâmica de pisos submetidos a atividades humanas rítmicas, com base na modelagem numérica e testes experimentais. O foco desta pesquisa é estudar o efeito da interação dinâmica entre pessoas e estrutura, representado por modelos biodinâmicos (sistemas massa-mola-amortecedor acoplado a estrutura) com poucos graus de liberdade. Deste modo, este trabalho investiga o comportamento dinâmico da estrutura com base nas formulações matemáticas, sob o ponto de vista do conforto humano. O modelo estrutural é composto por três andares com dimensões de 20m x 20m, área total de 1200m² (3 x 400m²) e um pé-direito de 4m, utilizado para aulas de ginástica aeróbica. A modelagem da estrutura foi realizada pelo programa ANSYS, baseado no método dos elementos finitos (MEF). Com o intuito de avaliar as funções matemáticas empregadas, foram obtidas experimentalmente as acelerações associadas a 32indivíduos praticando atividades rítmicas, de modo a introduzi-las no modelo numérico desenvolvido. Deste modo, a resposta estrutural dinâmica do modelo estrutural é avaliada em termos das acelerações de pico, RMS e VDV, de acordo com critérios de conforto humano

Experimental and Numerical Assessment of the Dynamical Behaviour of a Footbridge Under Human-Induced Loads

This research aims to perform an experimental and numerical assessment of an existing pedestrian footbridge located in the campus of the State University of Rio de Janeiro (UERJ), Rio de Janeiro/RJ, Brazil. The structural system is based on an internal reinforced concrete footbridge spanning 24.5m, constituted by concrete beams and slabs and being currently used for pedestrian crossing. The modal testing of the structure was performed by dynamic monitoring through accelerometers installed on the structure as well as by a vibrometer device based on Laser Doppler Vibrometry using the SIMO and SISO acquisition techniques, respectively. Then, these experimental results were calibrated with a numerical model by the use of finite element method (FEM) through the ANSYS program. Afterwards, a forced vibration analysis was performed on the structure based on human-induced loads considering two control groups: the first one is intended to excite the investigated footbridge to cause resonance motion with a controlled step frequency and the second one is related to freely random people crossing the footbridge as it occurs normally during its real life. Thus, the structural system dynamic response in terms of peak accelerations values were evaluated and compared to the current human comfort criteria