Investigation of the Flow Field in the Jack Rabbit II Mock Urban Environment Field Tests Using a 1:50 Scale Wind Tunnel Model

Accidental release of toxic chemicals can put workers and nearby populations at significant risk. Consequence assessment of accidents in urban environments is of particular interest. Urban geometries create wind channels between buildings, along with particularly dangerous areas downwind of buildings, where near-stagnant flow is present. Furthermore, recirculation zones can be formed between buildings, trapping high concentrations of toxic gases at ground level, particularly for denser-than-air gases. In 2015, the Department of Homeland Security conducted the Jack Rabbit II Field Test (JR-II) at Dugway Proving Ground, UT. During JR-II, chlorine was released at the center of a Mock Urban Environment (MUE) and three types of data were collected: visual recordings of the releases, concentration measurements at specific locations, and wind velocity and direction. Due to the toxicity and corrosive nature of chlorine, some measurements could not be made during the JR-II trials. In a subsequent study called Jack Rabbit II – Special Sonic Anemometer Study (JRII-S), wind velocity and turbulence were measured at points of interest within the MUE. Simulations of hazardous gas releases can be made in wind tunnel models, which provide for repeated tests with greater statistical analysis. Moreover, changes to test conditions can be made with relative ease and at lower costs. A 1:50 scale model of the JR-II MUE was constructed in the wind tunnel of the University of Arkansas. Laser Doppler Velocimetry (LDV) measurements show agreement between the approach wind characteristics in the tunnel model and field test. LDV velocity measurements within the MUE wind tunnel model also agree with the anemometry results obtained in JRII-S. Visualization of simulated chlorine releases in the wind tunnel shows good reproduction of release characteristics observed in the JR-II field tests. Mathematical analysis investigated if it was possible to obtain accurate 3D velocity measurements from a simplified 2D LDV setup. Error quantification showed that the simplified setup yields valid approximations for the vertical velocity and turbulence directions depending on the flow field characteristics, but high error is observed in the velocity and turbulence in the cross-wind component. After demonstrating that the wind tunnel models the JR-II and JRII-S field tests, Particle Image Velocimetry (PIV) experiments were conducted to provide velocity measurements that could not be obtained during JR-II. The wind tunnel model yields more comprehensive results than the pointwise measurements taken during JRII-S using sonic anemometers. Velocity measurements in a horizontal plane parallel to the ground were used to compare to computational fluid dynamics (CFD) simulations of the JRII-S field tests found in the literature. PIV measurements taken in the wind tunnel model pointed out concerns with those simulations. Reproduction of the JR-II field tests showed the velocity field in a section of the MUE before and during the chlorine release. The effect of the added momentum of the release in the flow field and in the height of the dividing streamline at CONEX 11.4 was investigated, with bigger impact observed at lower atmospheric momentum. Key Words: Wind tunnel modeling, gas release, Jack Rabbit II, Laser Doppler Velocimetry, Particle Image Velocimetr

Investigation of the Flow Field in the Jack Rabbit II Mock Urban Environment Field Tests Using a 1:50 Scale Wind Tunnel Model

Accidental release of toxic chemicals can put workers and nearby populations at significant risk. Consequence assessment of accidents in urban environments is of particular interest. Urban geometries create wind channels between buildings, along with particularly dangerous areas downwind of buildings, where near-stagnant flow is present. Furthermore, recirculation zones can be formed between buildings, trapping high concentrations of toxic gases at ground level, particularly for denser-than-air gases. In 2015, the Department of Homeland Security conducted the Jack Rabbit II Field Test (JR-II) at Dugway Proving Ground, UT. During JR-II, chlorine was released at the center of a Mock Urban Environment (MUE) and three types of data were collected: visual recordings of the releases, concentration measurements at specific locations, and wind velocity and direction. Due to the toxicity and corrosive nature of chlorine, some measurements could not be made during the JR-II trials. In a subsequent study called Jack Rabbit II – Special Sonic Anemometer Study (JRII-S), wind velocity and turbulence were measured at points of interest within the MUE. Simulations of hazardous gas releases can be made in wind tunnel models, which provide for repeated tests with greater statistical analysis. Moreover, changes to test conditions can be made with relative ease and at lower costs. A 1:50 scale model of the JR-II MUE was constructed in the wind tunnel of the University of Arkansas. Laser Doppler Velocimetry (LDV) measurements show agreement between the approach wind characteristics in the tunnel model and field test. LDV velocity measurements within the MUE wind tunnel model also agree with the anemometry results obtained in JRII-S. Visualization of simulated chlorine releases in the wind tunnel shows good reproduction of release characteristics observed in the JR-II field tests. Mathematical analysis investigated if it was possible to obtain accurate 3D velocity measurements from a simplified 2D LDV setup. Error quantification showed that the simplified setup yields valid approximations for the vertical velocity and turbulence directions depending on the flow field characteristics, but high error is observed in the velocity and turbulence in the cross-wind component. After demonstrating that the wind tunnel models the JR-II and JRII-S field tests, Particle Image Velocimetry (PIV) experiments were conducted to provide velocity measurements that could not be obtained during JR-II. The wind tunnel model yields more comprehensive results than the pointwise measurements taken during JRII-S using sonic anemometers. Velocity measurements in a horizontal plane parallel to the ground were used to compare to computational fluid dynamics (CFD) simulations of the JRII-S field tests found in the literature. PIV measurements taken in the wind tunnel model pointed out concerns with those simulations. Reproduction of the JR-II field tests showed the velocity field in a section of the MUE before and during the chlorine release. The effect of the added momentum of the release in the flow field and in the height of the dividing streamline at CONEX 11.4 was investigated, with bigger impact observed at lower atmospheric momentum. Key Words: Wind tunnel modeling, gas release, Jack Rabbit II, Laser Doppler Velocimetry, Particle Image Velocimetr

ANÁLISE DA PERCEPÇÃO DOS PRATICANTES DE ATIVIDADE FÍSICA SOBRE OS EFEITOS COLATERAIS ORIGINADOS PELO USO DE ESTERÓIDES ANABOLIZANTES NAS ACADEMIAS DO MUNICÍPIO DE ILICÍNEA- MG

A imagem corporal evidenciada pela mídia, a busca de corpos musculosos e o culto ao corpo desencadeou uma busca desenfreada por artifícios que permitam alcançar um ideal de beleza fora da realidade para a maior parte da população. Para obter esse ideal de corpo pessoas tomam medidas drásticas para satisfazerem suas necessidades. O uso de Esteroides Anabolizantes Androgênicos ou em seu termo mais popular: a “bomba” é uma solução rápida para tais anseios, mesmo os usuários reconhecendo o impacto negativo na saúde não se abstêm do consumo, tornando-o os Esteroides Anabolizantes Androgênicos cada vez mais conhecidos. Os anabolizantes são responsáveis por características anabólicas e androgênicas. As propriedades anabólicas geram aumento de massa muscular e forca, já as propriedades androgênicas estão relacionadas ao desenvolvimento das características sexuais masculinas. Os resultados deste neste trabalho demonstram que a prevalência de uso de esteróides anabólicos androgênicos no município de Ilicínea- MG encontra-se entre os índices descritos em outras literaturas. A pesquisa possibilitou traçar o perfil dos praticantes de atividade física entrevistados, que têm idade variando entre 15 e 57 anos. Mais de 60% dos entrevistados afirmaram saber o que são Esteroides Anabolizantes Androgênicos, 3% declaram fazer ou ter feito uso de Esteroides Anabolizantes Androgênicos, 63% declararam não acreditar que os usos de outras substâncias possam prevenir os efeitos adversos originados pelo uso Esteroides Anabolizantes Androgênicos de, 93% dos entrevistados acreditam que as doenças futuras provenientes do uso de Esteroides Anabolizantes Androgênicos podem ser prevenidas com o acompanhamento médico. Assim, deve-se buscar a conscientização deste público acerca dos prejuízos relacionados à utilização de Esteroides Anabolizantes Androgênicos, prevenindo a utilização destes e evitando danos à saúde

Hemorragia digestiva baixa e manejo de emergências: uma revisão integrativa

INTRODUÇÃO: O sangramento gastrointestinal pode acometer qualquer localidade e estrutura do trato, estruturas anatômicas são utilizadas para diferenciar o local de acometimento, como o ligamento de Treitz que divide os sangramentos superior e inferior. Características clínicas também são utilizadas nesta diferenciação, hematoquezia e melena são sinais comuns de sangramento no trato inferior. Percebe-se um aumento da prevalência do LGIB devido o envelhecimento e o constante uso de medicamentos que são predisponentes para esse tipo de sintoma. OBJETIVO: Avaliar as possíveis complicações e o manejo adequado em casos emergenciais de hemorragia digestiva baixa. METODOLOGIA: Trata-se de uma revisão integrativa na base de dados PUBMED utilizando os descritores “GASTROINTESTINAL HEMORRHAGE AND LOWER AND EMERGENCY’’ para artigos publicados entre 2018 e 2014. RESULTADOS: O LBIB é causa comum de hospitalização, 64% dos pacientes são do sexo masculino e a média de idade entre eles é de 49,6 anos. Os locais mais comuns em que se encontra o sangramento por meio da coloscopia são o reto (52,9%) e o cólon esquerdo (29,4%). Entre os principais fatores predisponentes de gravidade estão a idade (superior a 75 anos), IMC (menor que 18kg/m²) e os exames laboratoriais com as seguintes alterações: hemoglobina inferior a 11,0 g/dL, nível de albumina < 3,0 g/dL, nitrogênio ureico no sangue (BUN) ≥ 25 mg/dL, proteína C reativa (PCR) ≥ 1,0 mg/dL. O uso de DOAC apresentou influencia na gravidade e no local de acometimento do sinal clínico. CONCLUSÃO: A LGIB é uma causa comum de hospitalização e está relacionado geralmente a a doenças anorretais, pólipos colônicos, colite, câncer colorretal, angiodisplasia e a doença diverticular. Fatores como a idade e uso de medicamentos com função antittrombótica são de risco no que tange a evolução do doente. O tratamento deve se basear na angiografia e embolização, as cirurgias são recomendadas em casos emergenciais

Avanços nas Técnicas de Cirurgia Geral e Plástica para Correção de Fissura Palatina: Uma Revisão Sistemática

This article aims to evaluate advances in surgical techniques for the correction of cleft palate, highlighting the associated benefits and challenges. The specific objectives include identifying and describing the latest techniques, assessing their effectiveness in improving speech, comparing recovery times and complications, studying the success rate in preventing postoperative complications, and examining the need for complementary interventions such as speech therapy. The methodology used was a descriptive and qualitative bibliographic review, analyzing studies published between 2009 and 2024, in Portuguese and English. The databases consulted were PubMed, Scielo, and Google Scholar. The analysis focused on the effectiveness of surgical techniques in improving speech function, reducing recovery times, preventing postoperative complications, and evaluating the need for complementary interventions. The results indicate that recent advances, such as endoscopic surgery and the use of dynamic tension devices, have shown significant benefits, including less tissue trauma, reduced scarring, and better functional and aesthetic outcomes. Additionally, robotic surgery and 3D printing have contributed to personalized surgical planning, resulting in more precise and predictable procedures. Techniques such as Furlow and Bardach present higher success rates in speech correction and prevention of postoperative complications. The conclusion highlights the critical importance of surgical techniques for the correction of cleft palate, evidencing significant advances and associated challenges. Early surgical correction is essential to restore palate integrity, promoting improvements in speech, feeding, hearing, and facial aesthetics. A multidisciplinary approach involving surgeons, speech therapists, orthodontists, and other healthcare professionals is fundamental to ensure the best long-term outcomes for patients with cleft palate. Continued research in this area is crucial to enhance treatment strategies, ensure the safety and efficacy of procedures, and improve patients' quality of life.Este artigo tem como objetivo geral avaliar os avanços nas técnicas cirúrgicas para a correção de fissura palatina, destacando os benefícios e desafios associados. Os objetivos específicos incluem identificar e descrever as técnicas mais recentes, avaliar sua eficácia na melhora da fala, comparar tempos de recuperação e complicações, estudar a taxa de sucesso na prevenção de complicações pós-operatórias e examinar a necessidade de intervenções complementares, como fonoaudiologia. A metodologia utilizada foi uma revisão bibliográfica descritiva e qualitativa, analisando estudos publicados entre 2009 e 2024, em português e inglês. As bases de dados consultadas foram PubMed, Scielo e Google Scholar. A análise focou na eficácia das técnicas cirúrgicas em melhorar a função da fala, reduzir tempos de recuperação, prevenir complicações pós-operatórias e avaliar a necessidade de intervenções complementares. Os resultados indicam que os avanços recentes, como a cirurgia endoscópica e a utilização de dispositivos de tensão dinâmica, têm mostrado benefícios significativos, incluindo menor trauma tecidual, cicatrizes reduzidas e melhores resultados funcionais e estéticos. Além disso, a cirurgia robótica e a impressão 3D têm contribuído para o planejamento cirúrgico personalizado, resultando em procedimentos mais precisos e previsíveis. Técnicas como a de Furlow e a de Bardach apresentam melhores taxas de sucesso na correção da fala e na prevenção de complicações pós-operatórias. A conclusão destaca a importância crítica das técnicas cirúrgicas para a correção da fissura palatina, evidenciando os avanços significativos e os desafios associados. A correção cirúrgica precoce é essencial para restaurar a integridade do palato, promovendo melhorias na fala, alimentação, audição e estética facial. A abordagem multidisciplinar envolvendo cirurgiões, fonoaudiólogos, ortodontistas e outros profissionais de saúde é fundamental para garantir os melhores resultados a longo prazo para pacientes com fissura palatina. A continuidade de pesquisas nesta área é crucial para aprimorar as estratégias de tratamento, garantir a segurança e eficácia dos procedimentos e melhorar a qualidade de vida dos pacientes. &nbsp

Níveis disfuncionais de ansiedade relacionada ao Coronavírus em estudantes de medicina: Dysfunctional levels of Coronavirus-related anxiety in medical students

As preocupações com a saúde mental das pessoas afetadas pela pandemia de coronavírus não foram abordadas adequadamente. Isso é surpreendente, uma vez que tragédias em massa, particularmente aquelas que envolvem doenças infecciosas, muitas vezes desencadeiam ondas de medo e ansiedade elevados que são conhecidos por causar perturbações maciças no comportamento e no bem-estar psicológico de muitos na população. Assim, o objetivo desse trabalho é demonstrar os níveis disfuncionais de ansiedade relacionada ao coronavírus em estudantes de medicina. Para isso, foi realizado uma revisão sistemática sobre a temática

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016