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A moving immersed boundary method for unstructured grids is presented which offers several advantages over the standard ones with Cartesian grids. The flexibility provided by the unstructured grids allows for smaller grid sizes and meshing of complex flow configurations. The method features a conservative fluid domain characterization together with a flexible least-squares flow reconstruction to emulate the immersed body. The method is validated with several test cases and different grid types: polyhedral, triangular and Cartesian. A static problem is first simulated in order to demonstrate the expected second order accuracy. Then, a benchmark moving body problem is studied, where the method is shown to compute the correct velocity and pressure fields independently of the grid type. The effects of the cell topology in the spurious force oscillations (SFO) are also studied and the polyhedral grids are proven to be superior to their Cartesian and triangular counterparts. Finally, some examples of moving bodies in a computational domain with complex static boundaries are provided. The new method allows the use of unstructured grids for the outer fixed boundary, which allows good geometry conformance and therefore a better flow resolution. These grids can include a region with a reduced grid size and smooth transition, located at the body’s path.

This paper presents a study to develop a microwave irradiated fixed bed flow reactor for high temperature operations. One innovation introduced is the concept of catalytic bed sensitive to microwave heating which catalyzes the reaction and heats only the reaction site. Another innovation is on the cavity design, which is of a non-standard shape, which is a result from computational electromagnetic modelling. The focus of this work is on green ethylene production from ethanol dehydration. This reaction is conducted at high temperature and over a solid catalyst. Results showed a yield of 60.8% for green ethylene. This figure is of the same order than the ethylene conventional process, with the advantage that no carbon dioxide emission exists in the whole process. This concept may be thought of as a consequence of Microwave Chemistry evolution, which records nowadays has about 36 review papers, 15 books, more than a thousand scientific papers published per year, and 530 patents on microwave enhanced chemical processes.

Introducao Devido a pandemia do novo Coronavirus, a criopreservacao tem sido recomendada para garantir a continuidade do transplante de medula ossea (TMO) alogenico nao aparentado independentemente da fonte de celulas. Porem, a criopreservacao de celulas progenitoras hematopoeticas coletadas por puncao aspirativa da medula ossea (CPH,MO) e menos utilizada e poucos dados estao disponiveis na literatura. Objetivo descrever a experiencia do Centro de Processamento Celular do Cetebio/Fundacao Hemominas com a criopreservacao de CPH,MO para utilizacao terapeutica em TMO. Metodos Trata-se de um estudo do tipo serie de casos e a casuistica foi composta por oito unidades de CPH,MO criopreservadas entre 10/2020 e 06/2021. As unidades de CPH,MO foram submetidas a deseritrocitacao utilizando hidroxietilamido (HES) 450/0,7 e, em seguida, a centrifugacao para desplasmatizacao. O volume da camada leucocitaria foi ajustado para atingir a concentracao de celulas nucleadas final ≤2 × 108 NC/mL apos a adicao da solucao de criopreservacao (5%HES/5%DMSO). As unidades foram congeladas em freezer mecânico a -80°C e armazenadas em tanque a vapor de nitrogenio. Resultados oito unidades de CPH,MO foram criopreservadas para utilizacao em nove pacientes; uma unidade foi dividida para uso em dois pacientes pediatricos irmaos HLA identicos. Uma (11,1%) unidade foi criopreservada para o uso autologo e oito (88,9%) para uso alogenico nao aparentado. Cinco (55,6%) pacientes eram do sexo masculino. A media de idade dos pacientes foi 14,7 ± 19,1 anos (1–42). Um (11,1%) paciente possuia neuroblastoma, um (11,1%) LMC, um (11,1%) LMA, um (11,1%) sindrome de Griscelli, dois (22,2%) sindrome de Wiskott-Aldrich e tres (33,3%) LLA. O volume (mL) medio das unidades pre e pos-processamento foi 756,9 ± 411,7 e 78,7 ± 45,8, respectivamente. O volume (mL) medio de hemacias pre e pos-processamento foi 239,1 ± 150,8 e 27,02 ± 16,9, respectivamente. A media do total de celulas nucleadas (x108) pre e pos-processamento foi 153,07 ± 80,0 e 120,01 ± 67,7, respectivamente. A media de celulas CD34+ viaveis (x106) pre e pos-processamento foi 131,7 ± 74,0 e 120,2 ± 77,8, respectivamente. Quatro (50%) unidades apresentaram teste microbiologico positivo (Staphylococcus hominis, Staphylococcus epidermidis, Corynebacterium sp e Staphylococcus aureus). A viabilidade celular (%) media pos-descongelamento em amostras de segmento foi 66,1 ± 8,5. Os ensaios clonogenicos realizados em amostras pre-processamento (n = 6), pos-processamento (n = 8) e pos-descongelamento (n = 7) apresentaram crescimento positivo. Seis (66,6%) unidades foram liberadas para uso terapeutico, das quais cinco (83,3%) possuimos os dados da enxertia. Nenhum paciente apresentou falha de enxertia ou obito apos a infusao. O tempo medio de enxertia de granulocitos e plaquetas foi 17 ± 5,8 e 19,5 ± 9,2 dias, respectivamente. Discussao A reducao do volume possibilitou a criopreservacao do material, sendo que a recuperacao celular foi satisfatoria. Os testes de controle de qualidade realizados em todas etapas do processo evidenciaram a qualidade e seguranca do procedimento e foram corroborados pelos dados de enxertia. Alertamos, entretanto, sobre a necessidade de cuidados adicionais com os pacientes devido ao volume de hemacias a ser infundido e a contaminacao bacteriana, mais frequentemente observada nas unidades de CPH,MO. Conclusoes A criopreservacao CPH, MO apresentou resultados satisfatorios, demonstrando que a metodologia utilizada e segura e eficiente.

A new immersed boundary interpolation for discrete forcing methods is presented. The method decreases spurious oscillations in the pressure field and consequently in the body force calculations which are a common issue in several immersed boundary methods. The method applies a continuity constraint in the least-squares interpolation, and guarantees that adjacent interpolation polynomials are continuous between each other. This approach strictly enforces continuity in the flow reconstruction domain, reducing time discontinuities caused by the boundary conditions applied at the immersed boundary. Several moving body problems test cases are simulated, including a three dimensional one, to demonstrate the new method's capability of computing stable pressure fields, even for coarse grids and small CFL numbers, which are known to increase the pressure oscillations.

The reference adult male voxel phantom recommended by International Commission on Radiological Protection no. 110 was implemented in the Geant4 Monte Carlo code. Geant4 was used to calculate Dose Conversion Coefficients (DCCs) expressed as dose deposited in organs per air kerma for photons, electrons and neutrons in the Annals of the ICRP. In this work the AP and PA irradiation geometries of the ICRP male phantom were simulated for the purpose of benchmarking the Geant4 code. Monoenergetic photons were simulated between 15 keV and 10 MeV and the results were compared with ICRP 110, the VMC Monte Carlo code and the literature data available, presenting a good agreement.

Artigo também disponível em inglês: Relationship between leptin and body mass and metabolic syndrome in an adult population. http://www.elsevier.pt/en/revistas/revista-portuguesa-cardiologia-334/artigo/relationship-between-leptin-and-body-mass-and-metabolic-90165186 Objetivo Estudar a relação que a leptina tem com a obesidade (expressa em índice de massa corporal) e alguns componentes da síndrome metabólica (SM) numa amostra da população adulta. População e métodos Em 103 indivíduos, 42 homens e 61 mulheres, com idades superiores a 30 anos, clinicamente definidos como não diabéticos mas com patologia cardiovascular e/ou antecedentes familiares de doenças cardiovasculares (DCV), determinaram-se, além da leptina, a insulina, a glicemia em jejum e após ingestão de 75g de glicose, HDL-c, triglicéridos e calcularam-se os índices de resistência à insulina (IR-HOMA) e de massa corporal (IMC). Resultados O IMC, tomado como índice de obesidade geral, condicionou os níveis séricos da leptina. O IMC subiu, em ambos os sexos, à medida que os níveis séricos da leptina se elevaram do 1.° para o 3.° tercil da respetiva distribuição. Foi muito forte a correlação leptina/IMC com r=0,524 nos homens e r=0,603 nas mulheres, significância estatística elevada. Na previsão da hiperleptinemia, a posição cimeira foi assumida pelo IMC com AUC (area under curve) de 0,81 nos homens e 0,84 nas mulheres. Ao avaliar-se a magnitude da associação da leptina aos diferentes fatores de risco (regressão logística binária univariada) observaram-se valores muito altos de odds ratio (OR) para a relação leptina/IMC, em ambos os sexos (10,11 nos homens e 6,00 nas mulheres).Verificou-se mesmo (regressão logística multivariada) que a hiperleptinemia foi condicionada, em ambos os sexos, pela obesidade com OR de 9,30 nos homens e 8,1 nas mulheres, considerando IMC ≥ 30 kg/m2. - A hiperinsulinemia e a IR influenciaram profundamente a hiperleptinemia. Na previsão da IR, a leptina surgiu, em ambos os sexos, como primeiro elemento (AUC=0,89 nos homens e 0,85 nas mulheres) e, na previsão da hiperleptinemia, vêm logo a seguir à obesidade (IMC), a IR nos homens e a hiperinsulinémia nas mulheres com AUC respetivamente de 0,79 e 0,78. Foram fortes as correlações leptina/IR-HOMA e leptina/insulina, em ambos os sexos e enorme a influência que nos homens teve a hiperinsulinémia (OR=11,71) e a IR nas mulheres (OR=21,22). - Relativamente aos componentes da SM: Observou-se elevação dos respetivos níveis séricos, à medida que as concentrações da leptina subiram do 1.° para o 3.° tercil da respetiva distribuição (com exceção do HDL-c, que desceu). Conclusão O aumento da leptina sérica, sobretudo nos indivíduos obesos, deve constituir sinal de alerta para desiquilíbrios energéticos e do regimen alimentar, para a existência de hiperinsulinemia, de IR, de alterações em outros fatores de risco metabólicos que têm profunda influência nas DCV e diabetes tipo 2. [ENG] OBJECTIVE: To analyze the relationship between leptin and obesity expressed as body mass index (BMI) and certain components of the metabolic syndrome (MS) in an adult population. METHODS: The study included 103 subjects, 42 men and 61 women, aged over 30 years, clinically defined as non-diabetic but with personal or family history of cardiovascular disease. All subjects underwent fasting blood measurements of leptin, insulin, glucose, glucose after ingestion of 75g glucose, HDL cholesterol and triglycerides, and insulin resistance (IR) and BMI were calculated. RESULTS: BMI as an index of overall adiposity was strongly associated with serum leptin. BMI rose as serum leptin levels increased from the first to the third tertile; the correlation between leptin and BMI was strong, r=0.524 in men and r=0.603 in women, with high statistical significance (p

Heavy metals are not biodegradable and enter the food chain through a number of pathways causing progressive toxic actions due to the accumulation in different organs during a life span and long-term exposure to contaminated environments. Secondary ion mass spectrometry (SIMS) and inductively coupled plasma mass spectrometry (ICP-MS) were used to localize chromium in Eichhornia crassipes (Mart.) Solms. ICP-MS was used for the determination of Cr concentrations in water, sediments and plant samples in the Cachoeira basin, Bahia, Brazil. The results obtained by ICP-MS shows abnormally high values of Cr concentrations in water samples (0.38 mg/l), in soil samples (63 mg/g) and 70 mg/g in plant tissue. SIMS results show increased levels of Cr in the root cell wall and xylem vessel, these sites show high Cr accumulation. The ICP-MS data confirm E. crassipes like bioindicator plant. Chemical analysis using ICP-MS, confirms SIMS analysis on the presence of Cr in roots xylem cell walls. The use of ICP-MS, to investigate the same organs as the ones investigated by SIMS, provided complementary results on chromium study. # 2004 Elsevier B.V. All rights reserved.

We have developed a new spectro-electrochemical cell derived from the three-electrodes standard cell, in order to study the electrolyte/single-crystal interfaces by using surface X-ray diffraction. Results obtained with this cell are described here. We studied the phase transition of gold (111) in sulfuric acid. Preliminary results are shown concerning the overpotential deposition and the new possibilities that are opened by the use of a 2-D X-ray-sensitive detector. This set-up allowed us to follow in situ and in real time the morphology of Cu growth on Au (001), in free and surfactant-containing solution.

In this study we determined the cardiovascular effects produced by microinjection of angiotensin peptides [Angiotensin-(1-7) and Angiotensin II] and angiotensin antagonists (losartan, L-158,809, CGP 42112A. Sar1-Thr8-Ang II, A-779) into the rostral ventrolateral medulla of freely moving rats. Microinjection of angiotensins (12.5-50 pmol) produced pressor responses associated to variable changes in heart rate, usually tachycardia. Unexpectedly, microinjection of both AT1 and AT2 ligands produced pressor effects at doses that did not change blood pressure in anesthetized rats. Conversely, microinjection of Sar1-Thr8-Ang II and the selective Ang-(1-7) antagonist, A-779, produced a small but significant decrease in MAP an HR. These findings suggest that angiotensins can influence the tonic activity of vasomotor neurons at the RVLM. As previously observed in anesthetized rats, our results further suggest a role for endogenous Ang-(1-7) at the RVLM. The pressor activity of the ligands for AT1 and AT2 angiotensin receptor subtypes at the RVLM, remains to be clarified.