518 research outputs found
O acervo raro da biblioteca Milton de Albuquerque, da Embrapa Amazônia Oriental.
bitstream/item/63592/1/Oriental-Doc187.PD
Bibliografia de recursos naturais da Amazônia brasileira.
bitstream/item/145920/1/BIBLIOG-RECURSOS-NATURAIS.pd
NANOPTICS: in-depth analysis of NANomaterials for OPTICal localized surface plasmon resonance sensing
Thin films containing metal (gold, silver, etc.) nanoparticles are important platforms for molecularsensing based on the localized surface plasmon resonance (LSPR) phenomenon. To support their usein high-resolution LSPR spectroscopy systems, a software package, called NANOPTICS, was developed.It performs a statistical analysis of the LSPR band of the films, employing central moments of the normalized spectral distribution of optical transmittance. LSPR band parameters, signal-to-noise ratio and refractive index sensitivity are the outputs. It is shown that NANOPTICS can be a powerful tool to perform fast diagnostics of LSPR-based sensors’ sensitivity and to analyse their response to target analytes.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020; and by the projects NANOSENSING POCI-01-0145-FEDER-016902, with FCT reference PTDC/FIS-NAN/1154/2014; and project NANO4BIO POCI-01-0145-FEDER-032299, with FCT reference PTDC/FIS-MAC/32299/2017. Marco S. Rodrigues acknowledges FCT for his PhD Scholarship, SFRH/BD/118684/2016. Joel Borges acknowledges FCT for his Researcher Contract from project NANO4BIO
Estudo forense do sangue
Actualmente, a Ciência Forense recebe valiosa atenção tanto por académicos, cientistas, especialistas nas mais diversas áreas como por simples curiosos que em nada estão associados à CriminalÃstica, a sua popularidade está no auge. Esta ciência tem se tornado, cada vez mais, uma parte vital da Justiça Criminal. Como parte integrante desta ciência, a Medicina Legal ocupa um lugar de valor inestimável e as suas perÃcias de laboratório são indispensáveis na identificação do corpo de delito, principalmente quando os vestÃgios biológicos forem sangue, esperma, pêlos, saliva, entre outros.
O sangue é um dos vestÃgios biológicos mais comuns em qualquer cena de crime. Assim sendo o perito forense está bastante familiarizado com este tipo de vestÃgio, sendo um dos seus objectivos na análise da cena do crime a detecção de evidência de sangue.
Existem situações em que a mancha de sangue é evidente. Quando se localiza, por exemplo, próximo ao corpo alvejado por um disparo de arma de fogo. Contudo, há casos em que a mancha não é explÃcita. Existe a possibilidade, também, de que o criminoso limpe a cena do crime.
Foi realizada uma profunda e completa revisão bibliográfica de revistas, publicações da área e manuais e recomendações técnicas de laboratórios forenses de referência.
As análises forenses baseiam-se sobretudo nas técnicas e métodos da Imunologia, QuÃmica, BioquÃmica, bem como na Microscopia, Cristalografia, Cromatografia, Fluorescência, Fosforescência entre outros. Uma amálgama de princÃpios de técnicas que são adaptadas das outras ciências para ser possÃvel a sua utilização na área forense, uma vez que a amostragem é bastante diferente da das outras ciências. As amostras forenses são normalmente escassas, degradadas e com origem desconhecida, estas condições dificultam o seu manuseamento, obrigando a outro tipo de cuidados.
Genericamente é este o percurso que as amostras de sangue seguem para a sua detecção e identificação, com o objectivo maior que é a reconstituição e resolução do acto criminoso.
Actualmente, alguns destes testes vão caindo em desuso, muito por causa da mais recente tecnologia de Biologia Molecular, em que é possÃvel a determinação precisa e especifica do perfil genético da amostra e assim compara-la com os perfis dos suspeitos e vÃtimas possibilitando a identificação de forma inequÃvoca do agente causador do crime. Mas a importância destes testes é imensa na prática forense e justifica a sua utilização pelas suas inúmeras vantagens. São testes mais simples, rápidos, económicos, que permitem a obtenção de resultados por vezes imediatos facilitando o desenvolvimento das técnicas de biologia molecular, ou seja podem até ser vistos como testes iniciais de triagem com o objectivo final da identificação genética.
Assim, faz todo o sentido a sua utilização na prática forense. A sua exploração é uma enorme mais-valia para a resolução de crimes
Cork oak (Quercus suber L.) seedlings acclimate to elevated
Leaf gas-exchange, leaf and shoot anatomy,
wood density and hydraulic conductivity were investigated in
seedlings of Quercus suber L. grown for 15 months either at
elevated (700 lmol mol-1) or normal (350 lmol mol-1)
ambient atmospheric CO2 concentrations. Plants were
grown in greenhouses in a controlled environment: relative
humidity 50% (±5), temperature similar to external temperature
and natural light conditions. Plants were supplied
with nutrients and two water regimes (WW, well watered;
WS, water stress). After 6 months exposure to CO2
enrichment an increase in photosynthetic rate, a decrease in
stomatal conductance and a decrease in carbon isotope
discrimination (D13C) were observed, along with enhanced
growth and an increase in the number of branches and
branch diameter. Over the same period, the shoot weight
ratio increased, the root weight ratio decreased and the leaf
weight ratio was unaffected. The specific leaf area increased
due to an increase in total leaf thickness, mainly due to the
palisade parenchyma and starch. However, after 9 and
15 months of elevated CO2 exposure, the above-mentioned
physiological and morphological parameters appeared to be
unaffected. Elevated CO2 did not promote changes in vessel
lumen diameter, vessel frequency or wood density in stems
grown in greenhouse conditions. As a consequence, xylem
hydraulic efficiency remained unchanged. Likewise, xylem
vulnerability to embolism was not modified by elevated
CO2. In summary, elevated CO2 had no positive effect on
the ecophysiological parameters or growth of water stressed
plants
Combined tools for Surgical Case Packages contents and cost optimization: a preliminary study
This paper presents a solution proposal based on mathematical and statistical tools to optimize Surgical Case Packages of an Operating Room (OR) in a Portuguese public hospital that it is the most complex environment in a hospital. In this particular hospital, more than 27000 surgeries/year are performed, employing, sometimes, misadjusted composition of standard surgical packages and non-optimized grouping of surgical instruments. Problem consequences are, among others, high transport of
various surgical cases packages; high number of open cases and delays in surgical times following surgery. These type of problems are waste that do not add value to the service in the context of Lean Healthcare and must be eliminated using the most suitable tools. After the analysis, different tools were used: combinatorial analysis to optimize surgical cases composition and statistical analysis to identify the instruments usage and surgical basic case patterns. An optimization model was developed which produced a sterilizing initial solution of 135.24€. By identifying the most commonly employed instruments, it was concluded that some instruments have never been used and others rarely and some patterns were identified. The results achieved
were based on minor sample and in a form of data collection that needs some adjustment
Optical Coherence Tomography Features of Active and Inactive Retinal Neovascularization in Proliferative Diabetic Retinopathy
PURPOSE: To describe spectral domain-optical coherence tomography features of retinal neovascularization in proliferative diabetic retinopathy and thus to identify novel signs of new vessel activity.
METHODS: Retrospective, cross-sectional study. Data were collected over a 9-month period. Spectral domain optical coherence tomography scans were performed over areas of new vessel complexes (NVC) in both the disk and elsewhere, and were qualitatively graded by two masked observers. New vessel complexes activity was determined using clinical and angiographic criteria and correlated with spectral domain optical coherence tomography features.
RESULTS: Forty-three eyes of 30 patients with proliferative diabetic retinopathy were included. Sixty-one NVC lesions (neovascularization of the disk—37.7%, neovascularization elsewhere—62.3%) were captured by spectral domain-optical coherence tomography and analyzed. Among them, 63.9% were classified as active and 36.1% as quiescent. Five distinctive features were identified as significantly different between active and quiescent NVC: the presence of vitreous hyperreflective dots in active NVC (P = 0.002) and the presence of epiretinal membrane (P = 0.04), inner retinal tissue contracture (P = 0.03), vitreous invasion (P = 0.02), and protrusion towards vitreous (P = 0.002) in quiescent NVC.
CONCLUSION: In this exploratory study, the presence of vitreous hyperreflective dots, epiretinal membrane, inner retinal tissue contracture, vitreous invasion, and vitreous protrusion were identified as distinct signs of disease activity. Such parameters may be useful as a noninvasive imaging modality in eyes undergoing treatment for proliferative diabetic retinopathy
Background concentrations of polycyclic aromatic hydrocarbons metabolites in Portuguese firemen
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants
produced by the incomplete combustion of organic materials. PAHs may pose risks
to human health as many of the individual compounds are cytotoxic and mutagenic
to both lower and higher organisms, being some of them regarded as carcinogenic.
Pyrene is by far the most characterized PAH in all sample matrices, and is classified
as PAH marker of exposure while benzo(a)pyrene is considered the biomarker of
carcinogenic exposure to PAHs. Among the 16 PAHs established by US EPA as priority
pollutants, naphthalene, acenaphthene, fluorene, and phenanthrene are also found
in almost all the matrices.
Workers from industrial settings where airborne PAH levels are high such as coke
works and the primary aluminium industry, show excess rates of cancers. Firemen
are also exposed to high concentrations of PAHs during firefighting; however their
biomonitoring is difficult and epidemiological studies are scarce. During the last
decade, the urinary 1-hydroxypyrene has been used as a biomarker of environmental
and occupational exposure to PAHs. Still no standard reference or occupational
guidelines are available for any urinary PAH metabolite.
Within the present work, sixty healthy and no smoking Portuguese firemen
from ten Portuguese corporations from the district of Bragança (North of Portugal)
were evaluated regarding their levels of the most important urinary hydroxyl-
PAHs
- …