21 research outputs found
Wearable devices for health remote monitor system
It is feasible to see how communication and information technology have advanced at a rapid pace in today’s world. The introduction of wearable technology is one aspect contributing to this progress and has the potential to be an innovative solution to healthcare challenges since it may be utilized for illness prevention and maintenance, such as physical monitoring, as well as patient management. In order to solve some of the healthcare challenges, this paper proposes the development of an intelligent health monitoring system with alerts and continuous monitoring using wearable devices capable of collecting biometric data on human health. The concept was then proven by the development of a prototype using sensors connected to a micro-controller which transmits its information via MQTT to a Node-RED powered dashboard that handles the health metrics monitoring. The designed prototype has proven satisfactory to provide evidences that support the developed research questions.info:eu-repo/semantics/acceptedVersio
Subocclusive transvenous approach of dural arteriovenous fistula
Introdução: As fístulas arteriovenosas durais (FAVd) são usualmente adquiridas e quando
apresentam drenagem venosa cortical estão associadas a um risco elevado de hemorragia. Podem
ser tratadas por embolização (transarterial ou transvenosa), cirurgicamente ou pela combinação
das duas técnicas. A embolização por via transvenosa induz uma trombose iatrogénica do seio
venoso, acarretando risco de enfarte venoso e/ou hemorragia.
Objectivo: Rever os casos de FAVd do seio lateral submetidas a embolização transvenosa. O
nosso principal objectivo é avaliar a eficácia e a morbilidade deste tipo de tratamento e o segundo
é discutir as possíveis vantagens de uma abordagem suboclusiva na primeira sessão de tratamento.
Resultados: Os autores apresentam seis casos clínicos de FAVd, cujas formas de apresentação
foram: diminuição da acuidade visual (3); sopro pulsátil no ouvido (3); cefaleias (2);
hemorragia subaracnoideia (1); hipoacusia subjectiva (1); edema da papila (1); défice motor
(1). Angiograficamente: Cognard IIa (3), IIab (2) e IV (1), todas com envolvimento dos seios
laterais. As principais aferências eram: ACE ipsilateral (6); ACI ipsilateral (6); AV ipsilateral
(6); ACE contralateral (5); AV contralateral (5); ACI contralateral (3); ACP ipsilateral (1).
O tratamento inicial foi sempre a abordagem transarterial, com resultados angiográficos aceitáveis,
embora transitórios. Posteriormente optou-se pela via transvenosa com preenchimento do seio
lateral com GDC coils. Em cinco dos doentes decidiu-se pela suboclusão, com persistência de
algumas aferências. Em quatro, a angiografia subsequente demonstrou trombose “espontânea”
do seio lateral com resolução clínica e angiográfica da doença. Num deles a trombose ocorreu
ainda durante a sessão inicial. Todos os procedimentos decorreram sem complicações e nenhum
dos doentes desenvolveu novos défices neurológicos focais.
Conclusões: A abordagem transvenosa das FAVd obteve um sucesso técnico e clínico assinalável,
sem presença de complicações. Pensamos que a suboclusão do seio venoso com coils poderá
induzir menor alteração hemodinâmica aguda, possibilitando uma trombose mais lenta,
diminuindo o risco de complicações, mas com resolução angiográfica ulterior da FAVd
Pressure Studies on a High- Superconductor Pseudogap and Critical Temperatures
We report simultaneous hydrostatic pressure studies on the critical
temperature and on the pseudogap temperature performed through
resistivity measurements on an optimally doped high- oxide
. The resistivity is measured as
function of the temperature for several different applied pressure below 1GPa.
We find that both and increases linearly with the pressure. This
result demonstrate that the well known intrinsic pressure effect on is
also present at and both temperatures are originated by the same
superconducting mechanism.Comment: 4 pages and 2 figures in eps, final versio
Measurements and analysis of the upper critical field on an underdoped and overdoped compounds
The upper critical field is one of the many non conventional
properties of high- cuprates. It is possible that the
anomalies are due to the presence of inhomogeneities in the local charge
carrier density of the planes. In order to study this point, we
have prepared good quality samples of polycrystalline
using the wet-chemical method, which has demonstrated to produce samples with a
better cation distribution. In particular, we have studied the temperature
dependence of the second critical field, , through the magnetization
measurements on two samples with opposite average carrier concentration
() and nearly the same critical temperature, namely
(underdoped) and (overdoped). The results close to do not
follow the usual Ginzburg-Landau theory and are interpreted by a theory which
takes into account the influence of the inhomogeneities.Comment: Published versio
A Theory for High- Superconductors Considering Inhomogeneous Charge Distribution
We propose a general theory for the critical and pseudogap
temperature dependence on the doping concentration for high- oxides,
taking into account the charge inhomogeneities in the planes. The well
measured experimental inhomogeneous charge density in a given compound is
assumed to produce a spatial distribution of local . These differences
in the local charge concentration is assumed to yield insulator and metallic
regions, possibly in a stripe morphology. In the metallic region, the
inhomogeneous charge density yields also spatial distributions of
superconducting critical temperatures and zero temperature gap
. For a given sample, the measured onset of vanishing gap
temperature is identified as the pseudogap temperature, that is, , which
is the maximum of all . Below , due to the distribution of
's, there are some superconducting regions surrounded by insulator or
metallic medium. The transition to a superconducting state corresponds to the
percolation threshold among the superconducting regions with different
's. To model the charge inhomogeneities we use a double branched
Poisson-Gaussian distribution. To make definite calculations and compare with
the experimental results, we derive phase diagrams for the BSCO, LSCO and YBCO
families, with a mean field theory for superconductivity using an extended
Hubbard Hamiltonian. We show also that this novel approach provides new
insights on several experimental features of high- oxides.Comment: 7 pages, 5 eps figures, corrected typo
Development and validation of a method for the analysis of Ochratoxin A in roasted coffee by liquid chromatography/electrospray-mass spectrometry in Tandem (LC/ESI-MS/MS).
A method using LC/ESI-MS/MS for the quantitative analysis of Ochratoxin A in roasted coffee was described. Linearity was demonstrated (r = 0.9175). The limits of detection and quantification were 1.0 and 3.0 ng g-1, respectively. Trueness, repeatability and intermediate precision values were 89.0-108.8%; 2.4-13.7%; 12.5-17.8%, respectively. To the best of our knowledge, this is the first report in which Ochratoxin A in roasted coffee is analysed by LC/ESI-MS/MS, contributing to the field of mycotoxin analysis, and it will be used for future production of Certified Reference Material
Upper critical field calculations for the high critical temperature superconductors considering inhomogeneities
We perform calculations to obtain the curve of high temperature
superconductors (HTSC). We consider explicitly the fact that the HTSC possess
intrinsic inhomogeneities by taking into account a non uniform charge density
. The transition to a coherent superconducting phase at a critical
temperature corresponds to a percolation threshold among different
superconducting regions, each one characterized by a given .
Within this model we calculate the upper critical field by means of an
average linearized Ginzburg-Landau (GL) equation to take into account the
distribution of local superconducting temperatures . This
approach explains some of the anomalies associated with and why
several properties like the Meissner and Nernst effects are detected at
temperatures much higher than .Comment: Latex text, add reference