223 research outputs found
Rice Husk Ash Modified with Vanadium Pentoxide
Rice husk collected in Barreiras City, Bahia, Brazil was converted to rice husk ash (RHA) by acidic or basic leaching, followed by calcination. The resulting RHA was modified with vanadium pentoxide (2, 5, or 10 mass% of V2O5). The modified RHA samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). RHA exhibited FTIR bands associated with silica. After modification of acid-leached RHA with vanadium, the XRD data indicated the formation of V2O5 phases. Base-leached RHA modified with vanadium pentoxide showed the presence of the V2O5 phase only in the sample containing 10 mass% V2O5. The FTIR data indicated the formation of cristobalite, where bands associated with Si-O-V interactions were observed only for the sample with 10 mass% V2O5 prepared with acid-leached RHA.
DOI: http://dx.doi.org/10.17807/orbital.v9i2.91
Absorption of water waves in a two-dimensional numerical flume
In this work the absorption of water waves in a numerical wave flume is discussed
in terms of performance and robustness. A general formulation for the analysis of fluidstructure interaction problems using the Particle Finite Element Method (PFEM)1 is employed to simulate a numerical wave flume. The implementation of a wave dissipative zone changing the fluid viscosity properties is tested with the goal of absorbing waves reflected by a vertical
wall. The accuracy of this method is analyzed testing a set of viscosity distribution inside the dissipative zone using a prototype scale numerical wave flume.Peer ReviewedPostprint (published version
Wave reflection, transmission and spectral changes at permeable low-crested structures
Physical model tests were carried out in order to improve the understanding about the hydrodynamic processes that take place around a LCS when it is under wave attack. In particular, the wave transmission and reflection coefficients as well as the spectrum transformation were analysed for both emerged and submerged structures.
The results of the experiments indicated that there is a clear inverse proportionality between the transmission (Kt)
and reflection (Kr) coefficients and the wave steepness sop. This trend is much more noticeable for emerged than for submerged structures. A comparison with some widely employed formulae was also made; in most of the cases these expressions underpredicted Kt and overpredicted Kr. Moreover, the spectral changes in the waves transmitted through the structure were analyzed, showing a shift of energy to higher frequency bands greater than that observed in previous works. It was also noted that the higher the sop, the more likely it is for the transmitted energy to be retained in the lower frequency bands.Postprint (published version
Aspectos biológicos e espécies potenciais para restauração ecológica de áreas em desertificação no Sul do Piauí - Brasil
O presente estudo foi realizado em uma área em processo de desertificação no município de Gilbués – PI. Este trabalho teve como objetivo selecionar espécies lenhosas potenciais para restauração de áreas em processo de desertificação, por meio do levantamento fitossociológica e a relação com as propriedades químicas do solo. As espécies lenhosas (DNS > 1 cm) foi amostrada em um trecho de área desertificada em um transecto de 10000 m2 (1 ha) sendo subdividida em 10 parcelas de 1000 m2 (0,1). Myracroduon urundeuva Fr. All., Tabebuia aurea Benth. & Hook. e Astronium fraxinifolium Schott. baseado nos parâmetros fitossociológicos são espécies arbóreas com maior potencial para restauração de áreas desertificadas aliado ao fato de serem pioneiras com dispersão pelo vento. A vegetação lenhosa da área desertificada apresenta-se no inicio da sucessão ecológica com maior parte dos indivíduos nas menores classes de altura e diâmetro. Myracroduon urundeuva Fr. All. e Astronium fraxinifolium Schott. apresentaram correlação significativa com propriedades químicas do solo sendo mais adaptadas as condições edáficas das áreas desertificadas.
Rice Husk Ash Modified with Vanadium Pentoxide
Rice husk collected in Barreiras City, Bahia, Brazil was converted to rice husk ash (RHA) by acidic or basic leaching, followed by calcination. The resulting RHA was modified with vanadium pentoxide (2, 5, or 10 mass% of V2O5). The modified RHA samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). RHA exhibited FTIR bands associated with silica. After modification of acid-leached RHA with vanadium, the XRD data indicated the formation of V2O5 phases. Base-leached RHA modified with vanadium pentoxide showed the presence of the V2O5 phase only in the sample containing 10 mass% V2O5. The FTIR data indicated the formation of cristobalite, where bands associated with Si-O-V interactions were observed only for the sample with 10 mass% V2O5 prepared with acid-leached RHA.
DOI: http://dx.doi.org/10.17807/orbital.v9i2.91
Management of Psoriasis by Family Physicians: Referral Algorithm and Shared Management with Dermatology
Introduction: The implementation of models capable of improving referral quality, limiting the growth of waiting lists in hospitals, and ensuring the best possible treatment and follow-up of the psoriatic patient is of the utmost importance.
Material and methods: A panel of Family Physicians and Dermatologists discussed and created a simple and effective algorithm of referral for patients with psoriasis.
Results: The proposed algorithm starts when the Family Physician suspects of psoriasis. In case of diagnostic doubt, the patient should be referred to Dermatology. In case of a confirmed diagnosis, the Family Physician should assess the patient's severity and responder profile, evaluate comorbidities and assess the presence of psoriatic arthritis. If psoriasis is mild, topical treatments should be initiated, and if there is no clinical improvement or worsening of the disease, the patient should be referred to Dermatology. If psoriasis is moderate to severe, is located in high impact locations, or in pediatric age, the patient should be referred to Dermatology. In order to enable shared management in terms of follow-up and treatment of these patients, it is critical that the Family Physician has the necessary knowledge regarding the systemic treatments used in psoriasis and their side effects.
Discussion and conclusion: Only a shared management of the psoriatic patient can allow for the best treatment and follow-up of these patients, a more rational use of available medical resources, thus giving the patient the best possible quality of life.Introdução: A implementação de modelos capazes de melhorar a referenciação, por forma a garantir a qualidade e precocidade do diagnóstico, o melhor tratamento e seguimento do doente psoriático é fundamental.Material e Métodos: Um painel de médicos de Medicina Geral e Familiar e Dermatologia discutiu e criou um algoritmo de referenciação simples, eficaz e célere de doentes com psoríase.Resultados: O algoritmo proposto inicia-se quando o clínico de Medicina Geral e Familiar suspeita de psoríase. Caso haja dúvidas no diagnóstico, o doente deve ser referenciado para a dermatologia. No caso de um diagnóstico confirmado, compete ao clínico de Medicina Geral e Familiar avaliar a gravidade e perfil de respondedor do doente, rastrear comorbilidades e a possibilidade de artrite psoriática. Se a psoríase for ligeira, deverão ser iniciados tratamentos tópicos, sendo que, se não houver melhoria clínica ou ocorrer agravamento da doença, o doente deverá ser referenciado para a dermatologia. Se a psoríase for considerada moderada a grave, em localizações de elevado impacto, ou em idade pediátrica, o doente deverá ser referenciado para a dermatologia. Para que o seguimento e tratamento destes doentes seja partilhado, é fundamental que o médico de Medicina Geral e Familiar tenha o conhecimento necessário sobre os tratamentos sistémicos que o doente está a fazer e os seus efeitos adversos.Discussão e Conclusão: Apenas uma gestão partilhada do doente psoriático poderá tornar possível o melhor tratamento e seguimento destes doentes, a utilização mais racional dos recursos médicos disponíveis, proporcionando ao doente a melhor qualidade devida possível.info:eu-repo/semantics/publishedVersio
Early Holocene ritual complexity in South America: the archaeological record of Lapa do Santo (east-central Brazil)
Early Archaic human skeletal remains found in a burial context in Lapa do Santo in eastcentral Brazil provide a rare glimpse into the lives of hunter-gatherer communities in South America, including their rituals for dealing with the dead. These included the reduction of the body by means of mutilation, defleshing, tooth removal, exposure to fire and possibly cannibalism, followed by the secondary burial of the remains according to strict rules. In a later period, pits were filled with disarticulated bones of a single individual without signs of body manipulation, demonstrating that the region was inhabited by dynamic groups in constant transformation over a period of centuries
Osteoporose na pós-menopausa e a utilização de bisfosfonatos como opção terapêutica
Uma doença como característica de fragilidade óssea como a Osteoporose que afeta mais de 200 milhões de pessoas ao redor de todo o mundo, tem como principal característica ocorrência de fraturas de baixo impacto. Os pacientes que sobrevivem uma fratura de quadril tornam-se incapazes de manter uma vida independente, onde grande maioria necessita de um ambiente adequado. Num contexto geral esta doença não se apresenta com características clínicas especificas até o momento de uma primeira fratura. É uma patologia que acontece de forma crescente em termos de saúde em ambos os sexos, podendo ser dividida entre primária e secundária. A DMO tem seu pico atingido na idade adulta, mantendo-se constante em ambos os sexos até a idade de aproximadamente 40 anos, onde inicia sua redução espontânea após esta idade. Epidemiologicamente as fraturas vertebrais não são comparadas as fraturas de anca, por existir uma lacuna nos critérios de definição destas fraturas vertebrais. Um nutriente de bastante importância para regulação do tecido ósseo é o cálcio, onde sua ingesta é de extrema importância no tratamento de prevenção de osteoporose, assim como para a saúde óssea em qualquer idade, mesmo que suas necessidades diárias variem de idade para idade. Os bisfosfonatos são compostos sintéticos e possuem alta afinidade com cristais de cálcio no esqueleto, este confere maior resistência em sua degradação biológica. Os bisfosfonatos bloqueiam a quebra de síntese do farnesilpirofosfato e impede a isoprenilasão da guanosina trifosfato, que garante a integridade do citoesqueleto, sua absorção é limitada, tratando-se de uma absorção paracelular
MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal
Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio
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