Human femur assessment using isotropic and orthotropic materials dependent of bone density

The bone mass reduction and the deterioration of the tissue micron-architecture lead to a bigger fragility of the bone and to the consequent increase of the fracture risk. For this fact, it is considered excellent the quantification of the mass density and the verification of its influence in the bone resistance assessment. The apparent density is defined as the density without fluid influence, being the effective density at that includes the marrow mass, essentially fluid. This measurement is made through the use of a gray scale values on the medical image in study. The values in Hounsfield units are determined, being this scale later converted into measure of the bone density. With this measure an exponential relation will be used allowing calculate the biomechanics properties dependence for cortical and trabecular bone. With this work it is intended to assessment the susceptible weak zones, for a human femur with 70 years old, using the finite element method through ANSYS® program. The main objective is obtaining the stresses distributions, using different values of bone density and their relation with exponential laws for isotropic and orthotropic materials properties

Variability patterns and phenology of harmful phytoplankton blooms off southern Portugal: looking for region-specific environmental drivers and predictors

Harmful algal blooms (HABs) negatively impact coastal ecosystems, fisheries, and human health, and their prediction has become imperative for effective coastal management. This study aimed to evaluate spatialtemporal variability patterns and phenology for key toxigenic phytoplankton species off southern Portugal, during a 6-year period, and identify region-specific environmental drivers and predictors. Total abundance of species responsible for amnesic shellfish poisoning (Pseudo-nitzschia spp.), diarrhetic shellfish poisoning (Dinophysis spp.), and paralytic shellfish poisoning (G. catenatum) were retrieved, from the National Bivalve Mollusk Monitoring System public database. Contemporaneous environmental variables were acquired from satellite remote sensing, model-derived data, and in situ observations, and generalized additive models (GAMs) were used to explore the functional relationships between HABs and environmental variables and identify regionspecific predictors. Pseudo-nitzschia spp. showed a bimodal annual cycle for most coastal production areas, with spring and summer maxima, reflecting the increase in light intensity during the mixed layer shoaling stage, and the later stimulatory effects of upwelling events, with a higher bloom frequency over coastal areas subjected to stronger upwelling intensity. Dinophysis spp. exhibited a unimodal annual cycle, with spring/summer maxima associated with stratified conditions, that typically promote dinoflagellates. Dinophysis spp. blooms were delayed with respect to Pseudo-nitzschia spp. spring blooms, and followed by Pseudo-nitzschia spp. summer blooms, probably reflecting upwelling-relaxation cycles. G. catenatum occurred occasionally, namely in areas more influenced by river discharges, under weaker upwelling. Statistical-empirical models (GAMs) explained 7-8%, and 21− 54% of the variability in Pseudo-nitzschia spp. and Dinophysis spp., respectively. Overall, a set of four easily accessible environmental variables, surface photosynthetically available radiation, mixed layer depth, sea surface temperature, and chlorophyll-a concentration, emerged as the most influential predictors. Additionally, over the coastal production areas along the south coast, river discharges exerted minor negative effects on both HAB groups. Despite evidence supporting the role of upwelling intensity as an environmental driver of Pseudonitzschia spp., it was not identified as a relevant model predictor. Future model developments, such as the inclusion of additional environmental variables, and the implementation of species- and period-specific, and hybrid modelling approaches, may further support HAB operational forecasting and managing over complex coastal domains.info:eu-repo/semantics/publishedVersio

Solutions of the reflection equations for the Uq[G2]U_q[G_2] vertex model

We investigate the possible regular solutions of the boundary Yang-Baxter equation for the fundamental $U_q[G_2]$ vertex model. We find four distinct classes of reflection matrices such that half of them are diagonal while the other half are non-diagonal. The latter are parameterized by two continuous parameters but only one solution has all entries non-null. The non-diagonal solutions do not reduce to diagonal ones at any special limit of the free-parameters.Comment: 18 page

The thickness of the cortical bone in different maxillae using medical images

The aim of this study was to investigate whether there is a relationship between the thickness of the cortical bone of mandible human and the age and the sex of patient. In this work the measure of the cortical bone thickness was obtained in different computed tomography (CT). Different human mandibles were scanned using high resolution micro-CT instrument in which many axial slices were obtained. A total of four medical images were studied and observed. Two different groups were characterized. The first one, with two female maxillae (F): an old and a young patient. The second group of two males mandibles (M), with similar age. A comparison between the male and female sex was also obtained. The cortical bone thickness of the mandible may be affected by tooth extraction, age and sex patient. The use of this type of information is useful for complementary diagnostic information and treatment planning

Sequential injection titration of chloride in milk with potentiometric detection

In this work, a sequential injection system for the pseudo-titration of chloride in milk is described. Milk was directly aspirated into the system and sandwiched between two silver nitrate plugs (titrant). The aspirated zones were then propelled to the detector (Ag2S/Ag tubular electrode), where the depletion in the titrant silver concentration (due to the formation of a AgCl precipitate) was monitored. The results obtained by the developed sequential injection titration method were not statistically different from those provided by the potentiometric reference procedure with relative standard deviations better than 3.4%. The sampling rates achieved were 17 samples per hour.info:eu-repo/semantics/acceptedVersio

A Raman Study of Morphotropic Phase Boundary in PbZr1-xTixO3 at low temperatures

Raman spectra of PbZr1-xTixO3 ceramics with titanium concentration varying between 0.40 and 0.60 were measured at 7 K. By observing the concentration-frequency dependence of vibrational modes, we identified the boundaries among rhombohedral, monoclinic, and tetragonal ferroelectric phases. The analysis of the spectra was made in the view of theory group analysis making possible the assignment of some modes for the monoclinic phase.Comment: 5 pages, 4 figure

Fatty acis profile in Serra da Estrela cheese: an overview

Milk and dairy products are of major importance in the human diet, since they are an excellent source of well-balanced nutrients which are consumed in large amounts and are easy to manufacture. Most cheeses present in the market are made from cow's milk, with ewe’s and goat’s cheeses being considered delicacies derived from the unavailability of goat's and ewe’s milk in certain periods of the year, proleading to a final product with high prices that consumers tend to value given the quality of the final products. Serra Estrela (SE) cheese, a traditional variety manufactured in the center region of Portugal, is part of the national ancient cultural heritage. Made from raw sheep milk it is assumed as an iconic gourmet cheese, when compared with other Portuguese cheeses. In the present work, the evolution of the lipid fraction, namely unsaturated fatty acids such as monounsaturated and polyunsaturated (omega 3 fatty acids and omega 6 fatty acids), was evaluated for a period of 9 months. Chemically it was possible to verify differences in terms of the fatty acid profile between the analysed cheese samples. SE cheese was characterized by a relatively high content of monounsaturated fatty acids (MUFA) and the evaluation of the lipid profile of SE cheese allowed possible future work in determining bioactive lipid compounds with possible health promoting functions.info:eu-repo/semantics/publishedVersio

Idosos institucionalizados no concelho de Viseu: Hábitos alimentares

O envelhecimento da população, bem como a alteração da dinâmica da família, têm contribuído diretamente para o aumento do número de idosos institucionalizados. A incidência da desnutrição alcança níveis elevados nestes idosos, sendo essencial o seu diagnóstico precoce para a melhoria da sua qualidade de vida. Constitui objetivo primordial do estudo a avaliação do estado nutricional de idosos institucionalizados no concelho de Viseu, Portugal. A amostra (n=120) é constituída por idosos de ambos os sexos, institucionalizados, com idade igual ou superior a 65 anos, com capacidade para se colocar de pé, sem demência e que não sejam portadores de patologia passível de afetar a digestão, absorção ou utilização dos nutrientes. A avaliação do estado nutricional é determinada tendo em conta parâmetros antropométricos e dietéticos, através da avaliação da ingestão alimentar (registo de 3 dias) e Mini Nutricional Assessment (MNA). Os questionários aplicados estão validados para a população portuguesa idosa e foram aplicados após consentimento informado. Considerou-se um nível de confiança de 95%. A amostra estudada é maioritariamente feminina (70,0%), com uma idade média de 82,4±6,4 anos. A determinação do IMC mostrou que 12,5% dos idosos avaliados têm baixo peso (IMC 17,7±1,3); 46,7% são eutróficos (IMC 19,9±0,5); 11,7% apresentam excesso de peso (IMC 22,1±0,7), sendo 29,1% classificados como obesos (IMC 28,8±4,2). O MNA mostra que 65% dos idosos apresenta estado nutricional normal, estando sob risco de desnutrição 33,3%, verificando-se, este risco de desnutrição ser superior nos idosos ≥ 75 anos e na população feminina (3:1). A ingestão energética média por dia é significativamente inferior à recomendada (p≤0,05), sendo a ingesta de proteína e hidratos de carbono superior aos valores recomendados para a população (p≤0,05). O consumo lipídico é maioritariamente normolipídico (54,1%), devendo-se a um consumo reduzido de ácidos gordos monosaturados vs. polinsaturados.info:eu-repo/semantics/publishedVersio

Solution of the SU(N) Vertex Model with Non-Diagonal Open Boundaries

We diagonalize the double-row transfer matrix of the SU(N) vertex model for certain classes of non-diagonal boundary conditions. We derive explicit expressions for the corresponding eigenvectors and eigenvalues by means of the algebraic Bethe ansatz approach.Comment: 10 page

Portuguese study of familial dilated cardiomyopathy: the FATIMA study

Dilated cardiomyopathy (DCM) is a myocardial disease, characterized by ventricular dilatation and impaired systolic function, that in more than 30% of cases has a familial or genetic origin. Given its age-dependent penetrance, DCM frequently manifests in adults by signs or symptoms of heart failure, arrhythmias or sudden death. The predominant mode of inheritance is autosomal dominant, and in these cases mutations are identified in genes coding for cytoskeletal, sarcomeric or nuclear envelope proteins. To date, most studies aimed at molecular diagnosis of DCM have been in selected families, or in larger groups of patients, but screening for mutations in a limited number of genes. Consequently, the epidemiology of mutations in familial DCM remains unknown. There is thus a need for multicenter studies, involving screening for a wide range of mutations in several families and in cases of idiopathic DCM. The present article describes the methodology of a multicenter study, aimed at clinical and molecular characterization of familial DCM patients in the Portuguese population.A miocardiopatia dilatada (MCD) é uma doença do músculo cardíaco caracterizada pela dilatação ventricular e compromisso da função sistólica, sendo possível identificar, numa percentagem superior a 30% dos casos, uma origem familiar ou genética. Dada a penetrância dependente da idade, manifesta-se muitas vezes em adultos por sinais ou sintomas de insuficiência cardíaca, arritmias ou morte súbita. O padrão autossómico dominante predomina, sendo possível identificar, nestes casos, mutações em genes de proteínas do citoesqueleto celular, sarcómero ou membrana nuclear. Até ao momento, a maioria dos trabalhos visando o diagnóstico molecular nos casos de MCD foi realizada em famílias seleccionadas, ou em grupos mais abrangentes de doentes, mas rastreando mutações num número restrito de genes. Consequentemente a epidemiologia das mutações nos casos familiares de MCD continua por esclarecer. É neste contexto que se coloca a necessidade de efectuar estudos multicêntricos, envolvendo uma pesquisa mutacional diversificada em várias familias e nos casos idiopáticos de MCD. O presente artigo descreve a metodologia de um estudo multicêntrico que tem como objectivo a caracterização clínica e molecular de casos familiares de MCD na população portuguesa