120 research outputs found
A independência do Brasil como uma revolução: história e atualidade de um tema clássico
Este artigo retoma e problematiza o tema clássico da Independência do Brasil como um movimento revolucionário. Primeiramente, discute o conceito revolução em meio ao próprio processo de ruptura entre Brasil e Portugal; em seguida, analisa sinteticamente aspectos da historiografia desse problema nos séculos XIX e XX; por fim, reorganiza a questão de acordo com contribuições historiográficas que, nas últimas décadas, têm avançado no entendimento do processo histórico em si a partir da premissa de seu caráter revolucionário
Myths and Memories of the Nation
SMITH, Anthony D. Myths and Memories of the Nation. New York, Oxford University Press, 1999
Characterization of silicon photodiodes for diffuse reflectance signal extraction
Early detection of gastrointestinal (GI) can
cers is one
of most important concerns in medical field. Its detection at the
earliest stage is crucial to increase the patient survival chances.
Optical signals extraction and analysis, specifically diffuse
reflectance and intrinsic fluorescence, may impr
ove the ability to
detect GI dysplasia, once some morphological and biochemical
changes on the tissues (related with early cancer progre
ssion) can
modify these signals’
shape and intensity. The project under th
is
paper aims to develop a chip
-
sized spectros
copy microsystem for
the early detection of GI cancer. This paper presents the
characterization of silicon photodiodes (n+/p
-
epilayer type)
fabricated in a standard 0.7 μm CMOS process, with different
dimensions. The main goal is to conclude which photodio
de must
be fabricated for the microsystem implementation, taking into
account its capacity to extract the
signals in the relevant spectral
band (350 nm
–
750 nm), not comprising the microsystem
dimensions. With this study
,
it can be conclude
d
that the suit
able
photodiodes for the detection of those spectroscopic signals are
the
ones with
125 × 125 μm
2
or 100 × 100 μm
2
active area
, once
their quantum efficiency varies between 20% and 55%,
approximately, above 450 nm. In spite of the low photodiod
es
quantum efficiency (lower than 20%) below 450 nm, the viability
of using the 100 × 100 μm
2
photodiode to extract the diffuse
reflectance signal, between 350 nm and 750 nm, was proven using
a test phantom representative
of a GI tissue.This work is funded by FEDER funds through the "Eixo I do Programa Operacional Fatores de Competitividade (POFC) QREN, projects reference COMPETE: FCOMP-01-0124-FEDER-020241 and FCOMP-01-124-FEDER-037291 (PEst-C/FIS/UI0607/2013) and by FCT – Fundação para a Ciência e a Tecnologia, project reference PTDC/EBB-EBI/120334/2010. S. Pimenta thanks the FCT for the SFRH/BD/87605/2012 PhD grant
Prototype of an affordable pressure-controlled emergency mechanical ventilator for COVID-19
We present a viable prototype of a simple mechanical ventilator intended as a
last resort to ventilate COVID-19 patients. The prototype implements the
pressure-controlled continuous mandatory ventilation mode (PC-CMV) with
settable breathing rates, inspiration/expiration time ratios and FiO2
modulation. Although safe, the design aims to minimize the use of technical
components and those used are common in industry, so its construction may be
possible in times of logistical shortage or disruption or in areas with reduced
access to technical materials and at a moderate cost, affordable to lower
income countries. Most of the device can be manufactured by modest technical
means and construction plans are provided.Comment: This version differs from version 2 in that it includes toxicological
and bio-safety tests and updated electronic
Enzymatic inhibition studies of selected flavonoids and chemosystematic significance of polymethoxylated flavonoids and quinoline alkaloids in Neoraputia (Rutaceae)
Our taxonomic interest in the Neoraputia stimulated an investigation of N. paraensis searching for alkaloids. Fractions were monitored by ¹H NMR and ESI-MS/MS and only those which showed features of anthranilate alkaloids and flavonoids absent in the previous investigations were examined. Stems afforded the alkaloids flindersine, skimmianine, 8-methoxyflindersine and dictamnine; leaves yielded 3',4',7,8-tetramethoxy-5,6-(2,2-dimethylpyrano)-flavone, 3',4',5,7,8-pentamethoxyflavone, 5-hydroxy-3',4',6,7-tetramethoxyflavone, 3',4'-methylenedioxy-5,6,7-trimethoxyflavone and 5-hydroxy-3',4'-methylenedioxy-6,7-dimethoxyflavone. The alkaloids have remained undiscovered for 10 years. A number of flavonoids isolated from N. paraensis, N. magnifica, Murraya paniculata, Citrus sinensis graft (Rutaceae), Lonchocarpus montanus (Leguminosae) were evaluated for their ability to inhibit the enzymatic activity of the protein glyceraldehyde-3-phosphate dehydrogenase from Trypanosoma cruzi. Highly oxygenated flavones and isoflavone were the most actives.Nosso interesse quimiotaxonômico sobre Neoraputia nos estimulou a examinar N. paraensis, visando a busca de alcalóides. As frações foram monitoradas via RMN ¹H e ESI-EM/EM e foram analisadas somente aquelas cujos espectros apresentavam características de alcalóides do ácido antranílico e flavonóides não isolados anteriormente. Foram isolados do caule os alcalóides flindersina, skimmianina, 8-metoxiflindersina e dictamnina; das folhas os flavonóides 3',4',7,8-tetrametoxi-5,6-(2,2-dimetilpirano)-flavona, 3',4',5,7,8-pentametoxiflavona, 5-hidroxi-3',4',6,7-tetrametoxiflavona, 3',4'-metilenodioxi-5,6,7-trimetoxiflavona e 5-hidroxi-3',4'-metilenodioxi-6,7-dimetoxiflavona,. Os alcalóides do ácido antranílico não foram encontrados em dez anos. Vários flavonóides isolados de N. paraensis, N. magnifica, Murraya paniculata, enxerto de Citrus sinensis (Rutaceae) e Lonchocarpus montanus (Leguminosae) foram testados frente a gliceraldeído-3-fosfato desidrogenase de Trypanosoma cruzi, visando verificar seus potenciais em inibir a atividade da enzima. Os flavonóides polimetoxilados e um isoflavonóide foram os mais ativos.380387Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Production of electrospun fast-dissolving drug delivery systems with therapeutic eutectic systems encapsulated in gelatin
Fast-dissolving delivery systems (FDDS) have received increasing attention in
the last years. Oral drug delivery is still the preferred route for the administration of
pharmaceutical ingredients. Nevertheless, some patients, e.g. children or elderly people, have
difficulties in swallowing solid tablets. In this work, gelatin membranes were produced by
electrospinning, containing an encapsulated therapeutic deep-eutectic solvent (THEDES)
composed by choline chloride/mandelic acid, in a 1:2 molar ratio. A gelatin solution (30% w/
v) with 2% (v/v) of THEDES was used to produce electrospun fibers and the experimental
parameters were optimized. Due to the high surface area of polymer fibers, this type of
construct has wide applicability. With no cytotoxicity effect, and showing a fast-dissolving
release profile in PBS, the gelatin fibers with encapsulated THEDES seem to have promising
applications in the development of new drug delivery systems.The research leading to these results has received
funding from Fundação para a Ciência e a Tecnologia
(FCT) through the projects ENIGMA - PTDC/EQU-EPR/
121491/2010 and UID/CTM/50025/2013, LAQVREQUIMTE:
UID/QUI/50006/2013, UCIBIO-REQUIMTE:
UID/Multi/04378/2013 (co-financed by the ERDF under the
PT2020 Partnership Agreement [POCI-01-0145-FEDER-
007728]) and by FEDER through the COMPETE 2020
Programme. Marta Martins is grateful for financial support
from FCT through the grant BIM/PTDC/EQUEPR/121491/
2010/ENIGMA. This research has also received funding from
the European Union Seventh Framework Programme (FP7/
2007-2013) under grant agreement number REGPOTCT2012-316331-POLARIS and from the project BNovel
smart and biomimetic materials for innovative regenerative medicine approaches^ RL1 - ABMR - NORTE-01-0124- FEDER-000016) co-financed by North Portugal Regional
Operational Programme (ON.2 – O Novo Norte), under the
National Strategic Reference Framework (NSRF), through
the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio
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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