186 research outputs found
Determinants of the income velocity of money in Portugal: 1891–1998
This paper performs a long-run time series analysis of the behaviour of the income velocity of money in Portugal between 1891 and 1998 by assessing the importance of both macroeconomic and institutional factors and looking for particularities in the Portuguese case. We estimate two cointegration vectors for the income velocity of money, macroeconomic variables and institutional variables. It is apparent that one of these vectors reflects the relationship between income velocity and macroeconomic variables, while the other reflects the relationship between income velocity and institutional variables. Moreover, a regression analysis reveals that the usual U-shaped pattern is displayed with a relatively late inflection point located around 1970, which is consistent with the Spanish case. It is further noted that this is a feature of countries with a late economic and institutional development process.info:eu-repo/semantics/publishedVersio
Ordovician and Silurian geological heritage of the Arouca region (Portugal)
4 páginas, 3 figuras.-- Trabajo presentado en la 44ÂŞ SesiĂłn CientĂfica, JaĂ©n, 2008.The studied region is situated in the Aveiro district, about 50 km SW of Oporto (northern Portugal) and has a
rich geological, biological and cultural heritage. The Arouca Geopark was formally established there in late
2007, under the auspices of Arouca’s Municipal Chamber, to reunite 36 geosites from which some of them
involve remarkable Ordovician and Silurian rocks and fossils. Outcrops of both periods belong to the Valongo-
Tamames syncline of the Central Iberian Zone. Lower Palaeozoic rocks around the Canelas Slate Quarry are of
special interest, leading to the creation of a geotouristic route visiting three Ordovician units (Santa Justa quartzites,
Valongo shales and Sobrido quartzite plus glaciomarine diamictites) and one Silurian (graptolitic black shales),
as well as a Roman gold mine dug in the Lower Ordovician quartzites. However, the most outstanding geosite
is the quarry itself, where Middle Ordovician giant trilobites (up to 70 cm in size) and trilobite clusters (up to
thousands of specimens) occur in large slabs of slate and are recovered during the exploitation. The Geological
Interpretation Centre of Canelas, located near the quarry and open since 2006, is one of the main tourist
attractions of the Arouca Geopark, created to preserve and disseminate knowledge about trilobites and the
Ordovician world, and having received more than 10,000 visitors in its first 17 months.La empresa Ardósias Valério &
Figueiredo Lda., por su apoyo continuado al
trabajo paleontológico en la cantera de Canelas. A la Câmara Municipal de Arouca, por su sensibilidad en la gestión del patrimonio
geolĂłgico y la financiaciĂłn (a D.R.) para su
inventario. Este trabajo es una contribuciĂłn a los proyectos CGL2006-07628/BTE y
PTDC/CTE-GEX/64966/2006, financiados
por el Ministerio de EducaciĂłn y Ciencia español y la FundaciĂłn de Ciencia y TecnologĂa de Portugal, respectivamente.Peer reviewe
Thermal infrared remot sensing to discriminate soybean cultivars submitted to water deficits
A falta ou escassez de água produz anomalias no metabolismo do vegetal. O dĂ©ficit hĂdrico Ă© diretamente responsável pelo fechamento dos estĂ´matos e, consequentemente, pelo aumento da temperatura da folhagem, devido ao decrĂ©scimo da evaporação. Este trabalho tem como objetivo a avaliação do comportamento tĂ©rmico de várias cultivares de soja, submetidas ao dĂ©ficit hĂdrico. Neste experimento, cinco cultivares de soja foram submetidas a dois tratamentos: irrigado e nĂŁo-irrigado. Sobre as parcelas (trĂŞs repetições) foram obtidas temperaturas de dossel com um radiĂ´metro de infravermelho termal em diversos horários por vários dias. Paralelamente, foi medida a temperatura do ar, tanto no interior do campo experimental quanto na estação meteorolĂłgica. Os resultados mostraram que as cultivares podem ser diferenciadas em grupos apenas quanto ao comportamento tĂ©rmico somente quando em estresse hĂdrico: as cultivares nĂŁo-irrigadas apresentaram diferentes comportamentos tĂ©rmicos, facilitando sua separação em grupos distintos, de acordo com o seu mecanismo de controle hĂdrico. Os resultados mostraram o potencial de uso do radiĂ´metro infravermelho termal nos estudos de cultivares de soja, para o desenvolvimento de cultivares resistentes aos perĂodos de seca.The shortage or excess of water produces anomalous vegetal metabolism. The water deficit is directly responsible for closing the stomat and consequently raising the foliage temperature, due to the decreasing of energy consumption associated to the decrease of water evaporation. This work has as objective the evaluation of thermal behavior among several soybean cultivars submitted to water deficit. In this study the experiment consisted of irrigated and nonirrigated plots, with three plots for each soybean cultivar. Canopy temperature determinations were done with a thermal infrared radiometer (PRT-5) and, simultaneously, air temperature was also obtained. The results demonstrated lack of differentiation among irrigated soybean cultivars. However, in the nonirrigated plots, the soybean cultivavars presented different thermal behavior, facilitating their separation into distinct groups according to their mechanism of water loss control. The results show the potential of thermal infrared remote sensing in studies related to the development and selection of cultivars resistant to dry spells
Parainfluenza fusion peptide promotes membrane fusion by assembling into oligomeric porelike structures
© 2022 The Authors. Published by American Chemical SocietyParamyxoviruses are enveloped viruses harboring a negative-sense RNA genome that must enter the host’s cells to replicate. In the case of the parainfluenza virus, the cell entry process starts with the recognition and attachment to target receptors, followed by proteolytic cleavage of the fusion glycoprotein (F) protein, exposing the fusion peptide (FP) region. The FP is responsible for binding to the target membrane, and it is believed to play a crucial role in the fusion process, but the mechanism by which the parainfluenza FP (PIFP) promotes membrane fusion is still unclear. To elucidate this matter, we performed biophysical experimentation of the PIFP in membranes, together with coarse grain (CG) and atomistic (AA) molecular dynamics (MD) simulations. The simulation results led to the pinpointing of the most important PIFP amino acid residues for membrane fusion and show that, at high concentrations, the peptide induces the formation of a water-permeable porelike structure. This structure promotes lipid head intrusion and lipid tail protrusion, which facilitates membrane fusion. Biophysical experimental results validate these findings, showing that, depending on the peptide/lipid ratio, the PIFP can promote fusion and/or membrane leakage. Our work furthers the understanding of the PIFP-induced membrane fusion process, which might help foster development in the field of viral entry inhibition.This work was financially supported by FCT-Fundação para a Ciência e a Tecnologia, Portugal, through project PTDC/CCI-BIO/28200/2017 and by the European Union (H2020-FETOPEN-2018-2019-2020-01, grant no. 828774). This work was also financially supported by Project LISBOA-01-0145-FEDER-007660 (Microbiologia Molecular, Estrutural e Celular) funded by FEDER funds through COMPETE2020_Programa Operacional Competitividade e Internacionalização (POCI). M.V. and D.A.M. thank FCT for their PhD fellowships (SFRH/BD/148542/2019 and PD/BD/136752/2018, respectively). M.N.M. thanks FCT for the Post-Doc fellowship CEECIND/04124/2017. M.N.M. and D.L. thank the MACC for the computing hours in their HPC center (CPCA/A0/7329/2020 and CPCA/A0/7305/2020).info:eu-repo/semantics/publishedVersio
Binary orbits as the driver of Îł-ray emission and mass ejection in classical novae
Classical novae are the most common astrophysical thermonuclear explosions, occurring on the surfaces of white dwarf stars accreting gas from companions in binary star systems. Novae typically expel �10,000 solar masses of material at velocities exceeding 1,000 km/s. However, the mechanism of mass ejection in novae is poorly understood, and could be dominated by the impulsive flash of the thermonuclear runaway, prolonged optically thick winds, or binary interaction with the nova envelope. Classical novae are now routinely detected in GeV gamma-rays, suggesting that relativistic particles are accelerated by strong shocks in nova ejecta. Here we present high-resolution imaging of the gamma-ray-emitting nova V959 Mon at radio wavelengths, showing that its ejecta were shaped by binary motion: some gas was expelled rapidly along the poles as a wind from the white dwarf, while denser material drifted out along the equatorial plane, propelled by orbital motion. At the interface between the equatorial and polar regions, we observe synchrotron emission indicative of shocks and relativistic particle acceleration, thereby pinpointing the location of gamma-ray production. Binary shaping of the nova ejecta and associated internal shocks are expected to be widespread among novae, explaining why many novae are gamma-ray emitters
Metal alloys, matrix inclusions and manufacturing techniques of Moinhos de Golas collection (North Portugal): a study by micro-EDXRF, SEM–EDS, optical microscopy and X-ray radiography
"Article:820"A collection of 35 metallic artefacts comprising
various typologies, some of which can be attributed to the
Bronze Age and others to later periods, were studied to
provide detailed information on elemental composition,
manufacturing techniques and preservation state. Elemental
analysis by micro-EDXRF and SEM–EDS was performed
to investigate the use of different alloys and to
study the presence of microstructural heterogeneities, as
inclusions. X-ray radiography, optical microscopy and
SEM–EDS were used to investigate manufacturing techniques
and degradation features. Results showed that most
of the artefacts were produced in a binary bronze alloy
(Cu–Sn) with 10–15 wt% Sn and a low concentration of
impurities. Other artefacts were produced in copper or in
brass, the latest with varying contents of Zn, Sn and Pb. A
variety of inclusions in the metal matrices were also found,
some related to specific types of alloys, as (Cu–Ni)S2 in
coppers, or ZnS in brasses. Microstructural observations
revealed that the majority of the artefacts were subjected to
cycles of thermomechanical processing after casting, being
evident that among some artefacts different parts were
subjected to distinct treatments. The radiographic images
revealed structural heterogeneities related to local corrosion
processes and fissures that seem to have developed in
wear-tension zones, as in the handle of some daggers.
Radiographic images were also useful to detect the use of
different materials in one particular brass artefact, revealing
the presence of a possible Cu–Sn solder.This work was funded by FEDER funds through
the COMPETE 2020 Programme and National Funds through FCT—
Fundação para a Ciência e a Tecnologia under the project UID/CTM/
50025/2013 to CENIMAT/I3N. C2
TN/IST authors gratefully
acknowledge the FCT support through the UID/Multi/04349/2013
project. EF acknowledges FCT for the grant SFRH/BPD/97360/2013.
JF acknowledge FCT for the grant SFRH/BD/65143/2009. Part of this
project has been done in the framework of the FCT project ENARDAS
(PTDC/HISARQ/112983/2009).info:eu-repo/semantics/publishedVersio
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Head and neck cancer (HNC) has a high incidence in Brazil, with cancer of the oral cavity being one of the five most common cancers among Brazilians. Alcohol and tobacco consumption may contribute to synchronous or metachronous HNC and esophageal cancer. The early detection of superficial esophageal cancer and dysplasia in asymptomatic patients with HNC, after successfully treating the primary cancer, may provide an effective cure. A prospective study involving 60 patients with HNC was carried out at the State University of Campinas (UNICAMP) to screen for superficial esophageal cancer and dysplasia using endoscopy and a 2% lugol dye solution followed by biopsy of the suspicious areas. Five patients (8.3%) had superficial esophageal cancer, which was diagnosed as intraepithelial carcinoma in three of them (5.0%). In four patients, the superficial esophageal cancer was synchronous, and in one it was metachronous to HNC. Five patients (8.3%) had dysplasias in the esophageal epithelium (three were classified as mild and two as moderate). These results demonstrate the value of endoscopic screening of the esophagus using lugol dye in patients with HNC, particularly because superficial esophageal cancer is extremely difficult to detect by conventional methods in asymptomatic patients.22170-
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