1,429 research outputs found
Uma década de estudos palinológicos em sedimentos terciários continentais da região Sudeste do Brasil
Relações entre migmatização e deformação na região de Banabuiù (Domínio Ceará Central, Brasil)
A região de Banabuiú localiza-se no Domínio Ceará Central (DCC), NE do Brasil e é
constituída, em grande parte da sua extensão, por uma sequência sedimentar turbidítica de idade
paleoproterozóica, intensamente deformada e metamorfizada durante a orogenia brasiliana (ca. 600
Ma). O metamorfismo regional de alto grau (topo da fácies anfibolítica / fácies granulítica) atingiu as
condições de fusão parcial e deu origem a um complexo gnáissico-migmatítico, composto por
metatexitos estromáticos, diatexitos “schlieren” e diatexitos nebulíticos. Os contactos entre os
diferentes tipos litológicos são geralmente transicionais, embora tenha sido possível individualizar
faixas alternadas de metatexitos e diatexitos à escala cartográfica. Nos metatexitos estromáticos,
reconhecem-se com facilidade três componentes principais (a) o hospedeiro metassedimentar
(paleossoma), formado por uma alternância de metapelitos e metagrauvaques, com intercalações
pontuais de quartzitos e de rochas calcosilicatadas; (b) o fundido (leucossoma), representado por
veios quartzo-feldspáticos, frequentemente pegmatíticos e (c) o resíduo refractário (melanossoma),
constituído por finos leitos pelíticos envolvendo os leucossomas. Em contraste, os diatexitos são
texturalmente muito mais heterogéneos, contêm maiores proporções de leucossoma (>30%) e não
preservam as estruturas pré-migmatização.
As observações realizadas no campo permitiram identificar três gerações de leucossomas. A
primeira está associada à primeira fase de deformação (D1) e é marcada pela presença de veios de
leucossomas com espessura centimétrica, indicando que o início da fusão parcial das litologias
férteis da crusta terá ocorrido precocemente durante o engrossamento crustal. O segundo evento
de deformação (D2) é responsável pelo dobramento do bandado migmatítico D1 e pela formação de
abundantes quantidades de fundido. O último episódio de deformação dúctil (D3) parece estar
relacionado com a actuação da zona de cisalhamento de Orós (ZCO), que limita a área estudada a
este. Deu origem a dobras com planos axiais de direcção N-S a N30E, inclinação próxima de 90 e
eixos mergulhantes para norte e para sul. As lineações minerais e de estiramento, quando visíveis,
têm orientação N-S e baixo ângulo de mergulho para sul ou para norte. Durante a D3, formaram-se
leucossomas concordantes e discordantes com as estruturas D3. À escala regional, o bandado
migmatítico (D2+D3) é a estrutura dominante tanto nos diatexitos como nos metatexitos e chega a
adquirir um carácter milonítico nas zonas em que a deformação D3 é mais intensa. A proporção de
fundido parece aumentar progressivamente desde a D1 até às fases mais tardias (D2 e D3) e terá
culminado com a formação de um granito anatéctico de tipo S que aflora no sector ocidental da
região
Segmenting tourists by expenditure patterns: An instrument for enhancing tourism economic benefits on a Portuguese World Heritage site
Tourism is an activity with high potential for stimulating the development of local economies,
with different types of visitors having distinct environmental, social and economic effects on
destinations (Lundie, Dwyer, & Forsyth, 2007; Nickerson, Jorgenson, & Boley, 2016). Notwithstanding,
there is a research gap on strategies aimed at maximizing the economic relevance of tourism for local
tourism destinations using market segmentation, based on visitors’ daily expenditure level at the destination,
as a starting point (Lima, Eusébio, & Kastenholz, 2012). This gap becomes more evident when
we refer to World Heritage Sites (WHS) destinations (Amir, Osman, Bachok, & Ibrahim, 2016). This
study presents the results of the tourist market segmentation of a Portuguese municipality - Évora, a
UNESCO’s WHS, located in Alentejo. The study aims to identify the homogenous groups of visitors
that prevail in a WHS destination based on expenditure patterns and furthermore at contributing to the development of marketing strategies to enhance the economic development of this cultural destination.This research is funded with a grant from the FCT – National Funding Agency for
Science, Research and Technology, COMPETE, FEDER, Portugal 2020 under the project UID/HIS/00057/
2013 (POCI-01-0145-FEDER-007702) – CIDEHUS
In vitro cultivation of Brosimum gaudichaudii Tréc. (Moraceae)
O objetivo desta pesquisa foi avaliar o potencial organogenético de entrenós, discos foliares, e raízes de Brosimum gaudichaudii utilizando 12 diferentes combinações dos fitorreguladores 6-benzilaminopurina e ácido naftaleno acético, em meio MS (diluído à metade), sólido (6,5 g de ágar), e com 20 g.L-1 de sacarose. Independentemente das combinações hormonais testadas verificou-se a formação de calos friáveis (2 a 20 mm de diâmetro) em 90% dos entrenós usados como explantes. No entanto, os tratamentos testados não foram capazes induzir calos ou gemas em raízes e em discos foliares. O estudo anatômico revelou a formação de meristemóides nas regiões mais externa e mais interna dos calos. Os resultados obtidos poderão servir de base para novos testes de indução de calos na espécie.The objective of this research was to evaluate the organogenic potential of internodes, leaf discs and roots of Brosimum gaudichaudii using 12 different combinations of the plant growth regulators 6-benzylaminopurine and naphthalene acetic acid in MS medium (half strength), solid medium (6.5 g agar) and sucrose medium (20 g.L-1). Regardless the hormonal combination tested, we observed the formation of friable calluses (2 - 20 mm wide) in 90% of the internode explants. However, the treatments were not able to induce callus or buds on roots and leaf discs. The anatomical analysis revealed meristemoid formation in the outer and inner regions of the calluses. The results may serve as the basis for further testing of callus induction in this species
Dynamics of interacting phantom and quintessence dark energies
We present models, in which phantom energy interacts with two different types
of dark energies including variable modified Chaplygin gas (VMCG) and new
modified Chaplygin gas (NMCG). We then construct potentials for these cases. It
has been shown that the potential of the phantom field decreases from a higher
value with the evolution of the Universe.Comment: 7 pages, 6 figures, accepted for publication in Astrophysics and
Space Scienc
In silico before in vivo: How to predict the heating efficiency of magnetic nanoparticles within the intracellular space
This work aims to demonstrate the need for in silico design via numerical simulation to produce optimal Fe 3 O 4 -based magnetic nanoparticles (MNPs) for magnetic hyperthermia by minimizing the impact of intracellular environments on heating efficiency. By including the relevant magnetic parameters, such as magnetic anisotropy and dipolar interactions, into a numerical model, the heating efficiency of as prepared colloids was preserved in the intracellular environment, providing the largest in vitro specific power absorption (SPA) values yet reported. Dipolar interactions due to intracellular agglomeration, which are included in the simulated SPA, were found to be the main cause of changes in the magnetic relaxation dynamics of MNPs under in vitro conditions. These results pave the way for the magnetism-based design of MNPs that can retain their heating efficiency in vivo, thereby improving the outcome of clinical hyperthermia experiments
Estratégia de sensibilização dos alunos universitários para o tema do turismo acessível: O caso da licenciatura em Turismo da Universidade de Évora
Vive-se atualmente um contexto de reflexão internacional por parte de diversos investigadores
que reconhecem a necessidade de reinventar os planos de estudos e as suas dinâmicas de formação,
de modo a que os alunos fiquem mais aptos a enfrentar os desafios do mercado de trabalho (e.g. Ayikoru,
Tribe & Airey, 2009; Fidgeon, 2010; Hoidn & Kärkkäinen, 2014; OECD, 2016; Stergiou, Airey & Riley,
2008). São valorizadas iniciativas que envolvam dinâmicas educativas inovadoras e que sejam capazes
de incutir nos alunos as qualidades humanas necessárias para desenvolver um sentido mais crítico sobre
os problemas sociais que realmente afetam a nossa sociedade e, em consequência, possam ter efeitos
positivos no nível de competitividade das empresas.
Neste contexto, o presente trabalho tem como objetivo apresentar o contexto no qual a licenciatura
em Turismo da Universidade de Évora promoveu uma iniciativa, de carácter voluntário e inovador, para
comemorar o Dia Mundial de Turismo, em 27 de setembro de 2016, subordinado ao tema “Tourism For
All – Promoting Universal Accessibility”. Em anos anteriores, o Dia Mundial de Turismo foi comemorado
com a dinamização de iniciativas que visavam sensibilizar a população local para a existência deste acontecimento. No entanto, este ano optou-se por uma estratégia educativa que pudesse reforçar as
competências dos alunos sobre este tema de relevante atualidade e importância.Este trabalho é financiado por fundos nacionais através da Fundação para a Ciência
e a Tecnologia e pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do COMPETE
2020 – Programa Operacional Competitividade e Internacionalização (POCI) e PT2020, no âmbito do
projeto UID/HIS/00057 – POCI-01-0145-FEDER-00770
Application of imaging technologies in breast cancer detection: A review article
One of the techniques utilised in the management of cancer in all stages is multiple biomedical imaging. Imaging as an important part of cancer clinical protocols can provide a variety of information about morphology, structure, metabolism and functions. Application of imaging technics together with other investigative apparatus including in fluids analysis and vitro tissue would help clinical decision-making. Mixed imaging techniques can provide supplementary information used to improve staging and therapy planning. Imaging aimed to find minimally invasive therapy to make better results and reduce side effects. Probably, the most important factor in reducing mortality of certain cancers is an early diagnosis of cancer via screening based on imaging. The most common cancer in women is breast cancer. It is considered as the second major cause of cancer deaths in females, and therefore it remained as an important medical and socio-economic issue. Medical imaging has always formed part of breast cancer care and has used in all phases of cancer management from detection and staging to therapy monitoring and post-therapeutic follow-up. An essential action to be performed in the preoperative staging of breast cancer based on breast imaging. The general term of breast imaging refers to breast sonography, mammography, and magnetic resonance tomography (MRT) of the breast (magnetic resonance mammography, MRM). Further development in technology will lead to increase imaging speed to meet physiological processes requirements. One of the issues in the diagnosis of breast cancer is sensitivity limitation. To overcome this limitation, complementary imaging examinations are utilised that traditionally includes screening ultrasound, and combined mammography and ultrasound. Development in targeted imaging and therapeutic agents calls for close cooperation among academic environment and industries such as biotechnological, IT and pharmaceutical industries. © 2019 Zeinab Safarpour Lima, Mohammad Reza Ebadi, Ghazaleh Amjad, Ladan Younesi
Investigation into breast cancer and partial breast reconstruction: A review
Growing increasingly in South America, Africa and Asia, breast cancer is known as the dominant type of cancer in women. Different treatments are available for breast cancer, among which surgery is the most widely used, but researchers are trying to develop new strategies. One of the most prominent surgical methods is referred to as oncoplastic surgery, that helps to remove segments of malignant breast tissue. This type of surgery aims to obtain vast surgical margins, while the remaining tissue is rearranged so that the better cosmetic outcome is obtained. This review will investigate the breast cancer and then discuss partial breast reconstruction. Before outlining the procedures, the different types of partial breast reconstruction will be discussed. Finally, advantages and disadvantages will be outlined. MEDLINE database was used to conduct the search. The main terms used were �Conservation Breast Surgery Reconstruction� AND �Oncoplastic Surgery�, �Partial Mastectomy Reconstruction� AND �Conservative Breast Surgery Reconstruction�, �oncoplastic� All Fields, �breast� AND �surgery� OR �surgery� operative�, �oncoplastic� (�breast�)�. The bibliographies of relevant papers were manually searched up to October 2018, but more recent voices are also included. © 2019 PAGEPress Publications. All rights reserved
Low-Dimensional Assemblies of Magnetic MnFe2O4 Nanoparticles and Direct In Vitro Measurements of Enhanced Heating Driven by Dipolar Interactions: Implications for Magnetic Hyperthermia
Magnetic fluid hyperthermia (MFH), the procedure of raising the temperature of tumor cells using magnetic nanoparticles (MNPs) as heating agents, has proven successful in treating some types of cancer. However, the low heating power generated under physiological conditions makes it necessary a high local concentration of MNPs at tumor sites. Here, we report how the in vitro heating power of magnetically soft MnFe2O4 nanoparticles can be enhanced by intracellular low-dimensional clusters through a strategy that includes: (a) the design of the MNPs to retain Neel magnetic relaxation in high-viscosity media, and (b) culturing MNP-loaded cells under magnetic fields to produce elongated intracellular agglomerates. Our direct in vitro measurements demonstrated that the specific loss power (SLP) of elongated agglomerates (SLP = 576 +/- 33 W/g) induced by culturing BV2 cells in situ under a dc magnetic field was increased by a factor of 2 compared to the SLP = 305 +/- 25 W/g measured in aggregates freely formed within cells. A numerical mean-field model that included dipolar interactions quantitatively reproduced the SLPs of these clusters both in phantoms and in vitro, suggesting that it captures the relevant mechanisms behind power losses under high-viscosity conditions. These results indicate that in situ assembling of MNPs into low-dimensional structures is a sound possible way to improve the heating performance in MFH
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