55 research outputs found
The North Atlantic oscillation and European vegetation dynamics
The relationship between vegetation greenness and the North Atlantic Oscillation (NAO) is assessed over
Europe. The study covers the 21-year period from 1982 to 2002 and is based on monthly composites of the Normalised
Difference Vegetation Index (NDVI) and Brightness Temperature from the Global Inventory Monitoring and Modelling
System (GIMMS) as well as on monthly precipitation from the Global Precipitation Climatology Centre (GPCC).
A systematic analysis is first performed of point correlation fields over the 21-year period between the winter NAO
index and spring and summer NDVI, followed by an assessment of the vegetation response to precipitation and temperature
conditions in winter, over two contrasting regions, namely the Iberian Peninsula and Northeastern Europe. Finally, the
impact of NAO on vegetation dynamics over the two regions is evaluated by studying the corresponding annual cycles of
NDVI and comparing their behaviour for years associated with opposite NAO phases.
Over the Iberian Peninsula there is strong evidence that positive (negative) values of winter NAO induce low (high)
vegetation activity in the following spring and summer seasons. This feature is mainly associated with the impact of NAO
on winter precipitation, together with the strong dependence of spring and summer NDVI on water availability during the
previous winter. Northeastern Europe shows a different behaviour, with positive (negative) values of winter NAO inducing
high (low) values of NDVI in spring, but low (high) values of NDVI in summer. This behaviour mainly results from the
strong impact of NAO on winter temperature, associated with the critical dependence of vegetation growth on the combined
effect of warm conditions and water availability during the winter seaso
Evaluating the impact of extreme temperature based indices in the 2003 heatwave excessive mortality in Portugal
This paper analyses the impact of the 2003 European heatwave on excessive human mortality in Portugal, a country that presents a relatively high level of exposure to heatwave events. A total of 2399 excessive deaths are estimated in continental Portugal, which implies an increase of 58% over the expected deaths. When these values are split by gender, it is seen that women increase (79%), was considerably higher than that recorded for men (41%). The increment of mortality due to this heatwave was detected for all the 18 districts of the country, but its magnitude was significantly higher in the inner districts close to the Spanish border. When we split by gender all districts reveal significant mortality increments for women, while the impact in men’s excess deaths is not significant over 3 districts. Several temperature derived indices were used and evaluated in their capacity to explain, at the regional level, the excessive mortality (ratio between observed and expected deaths) by gender. It is shown that the best relationship is found for the total exceedance of extreme days, an index combining the length of the heatwave and its intensity. Both variables hold a linear relationship with r = 0.79 for women and a poorer adjustment (r = 0.50) for men. Additionally, availability of mortality data split by age also allowed obtaining detailed information on the structure of the population in risk, namely by showing that statistically significant increments are concentrated in the last three age classes (45–64, 65–74 and 75 or more). The use of air conditioning systems in some Portuguese hospitals had a major impact on the decrease (up to 40%) in excessive mortality values. A finer approach is relevant for prevention strategies, since it allows to identify better the target population of any preventive strategy regional and national authorities may be interested to implement
Effects of recent minimum temperature and water deficit increases on Pinus pinaster radial growth and wood density in southern Portugal
Western Iberia has recently shown increasing frequency of drought conditions coupled
with heatwave events, leading to exacerbated limiting climatic conditions for plant
growth. It is not clear to what extent wood growth and density of agroforestry species
have suffered from such changes or recent extreme climate events. To address this
question, tree-ring width and density chronologies were built for a Pinus pinaster stand
in southern Portugal and correlated with climate variables, including the minimum, mean
and maximum temperatures and the number of cold days. Monthly and maximum
daily precipitations were also analyzed as well as dry spells. The drought effect was
assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar
drought index, between 1 to 24-months. The climate-growth/density relationships
were evaluated for the period 1958-2011. We show that both wood radial growth
and density highly benefit from the strong decay of cold days and the increase of
minimum temperature. Yet the benefits are hindered by long-term water deficit, which
results in different levels of impact on wood radial growth and density. Despite of the
intensification of long-term water deficit, tree-ring width appears to benefit from the
minimum temperature increase, whereas the effects of long-term droughts significantly
prevail on tree-ring density. Our results further highlight the dependency of the species
on deep water sources after the juvenile stage. The impact of climate changes on longterm
droughts and their repercussion on the shallow groundwater table and P. pinaster’s
vulnerability are also discussed. This work provides relevant information for forest
management in the semi-arid area of the Alentejo region of Portugal. It should ease
the elaboration of mitigation strategies to assure P. pinaster’s production capacity and
quality in response to more arid conditions in the near future in the regioninfo:eu-repo/semantics/publishedVersio
Drought impacts on vegetation activity, growth and primary production in humid and arid ecosystems
9 Pags., 5 Figs.[EN] We have evaluated the response of the Earth biomes to drought using a new global dataset that captures drought effects on vegetation at various time scales. We show that arid and humid biomes are both affected by drought, and that the time scale on which droughts most intensively affects vegetation plays a key role in determining the sensitivity of biomes to drought. Arid biomes respond to drought at short time scales because plants have mechanisms allowing them to rapidly adapt to changing water availability. Humid biomes also respond to drought at short time scales, probably because there plant species show a poor adaptability to water shortage. Sub-humid biomes respond to drought at long time scales because plants are adapted to withstand water deficit, but they lack the rapid post-drought recovery observed in arid biomes.[ES] En este trabajo se evalúa la respuesta de los diferentes biomas terrestre a la sequía mediante una base de datos nueva que captura el efecto de la sequía sobre la vegetación a diferentes escalas temporales. Se ha comprobado que los biomas característicos de zonas áridas y húmedas se ven afectados por la sequía, y que la escala temporal de la sequía juega un papel clave al determinar la sensibilidad de los biomas a la sequía. Los biomas áridos responden a las sequías medidas a escalas temporales cortas, debido a que las plantas tienen mecanismos que les permitan adaptarse rápidamente a la disponibilidad de agua. Los biomas húmedos también responden a la sequía a escalas temporales cortas, probablemente debido a que las especies ubicadas allí muestran una mala adaptación a la escasez de agua. Los biomas subhúmedos responden a la sequía a escalas de tiempo más largas, porque las plantas están adaptadas para soportar el déficit de agua, pero carecen de la rápida recuperación observada tras la sequía en los biomas áridos.This work was supported by projects financed by the Spanish Commission of Science and Technology (CGL2O1 1-27574-C02-02, CGL2O1 1-27536 and CGL2O1 1-26654) and the Aragón Government. J.J.C. thanks the support of ARAID and A.S-L. was supported by a postdoctoral fellowship from the Generalitat de Catalunya (2009 BP-A 00035).Peer reviewe
Drought impacts on vegetation activity, growth and primary production in humid and arid ecoystems
We have evaluated the response of the Earth biomes to drought using a new global dataset that
captures drought effects on vegetation at various time scales. We show that arid and humid biomes
are both affected by drought, and that the time scale on which droughts most intensively affects
vegetation plays a key role in determining the sensitivity of biomes to drought. Arid biomes respond
to drought at short time scales because plants have mechanisms allowing them to rapidly adapt to
changing water availability. Humid biomes also respond to drought at short time scales, probably
because there plant species show a poor adaptability to water shortage. Sub-humid biomes respond
to drought at long time scales because plants are adapted to withstand water deficit, but they lack the
rapid post-drought recovery observed in arid biomes.Peer Reviewe
Teorias discursivas em diálogo: perspetivas e análises
O volume inclui quatro capítulos: "Texto e contexto: Que relações?", de Carlos A. M. Gouveia e Joana Vieira Santos; "Classificações textuais e documentos programáticos de Português", de Paulo Nunes da Silva, Luís Filipe Barbeiro e Fausto Caels; "Géneros escolares e aprendizagens", de Luís Filipe Barbeiro, Fausto Caels e Paulo Nunes da Silva; e "Reconto e relato: Propostas de análise de narrativas orais em contexto escolar", de Carla Marques e Célia BarbeiroFinanciado por fundos nacionais através da FCT – Fundação para a Ciência e a Tecnologia, I.P., no âmbito do projeto UID/04887/2020info:eu-repo/semantics/publishedVersio
Interferência de ondas curtas pulsadas na adesividade e na fagocitose de macrófagos em ratos com desnutrição neonatal
Tendo em vista a relação estabelecida entre desnutrição neonatal e atividade celular ligada ao sistema imune, macrófagos peritoniais de ratosWistar machos, desnutridos e recuperados, foram expostos à diatermia de ondas curtas pulsadas (DOCP) e a campo magnético (CM) alternado em freqüência ultrabaixa para verificar in vitro as possíveis alterações no índice de aderência e na atividade fagocítica. Foram submetidos a DOCPmodulada em 30 Hz, 50 Hz e 430 Hz na técnica de Schliephake e na técnica convencional em paralelo, e a um CM de 60 Hz. Foi constatadoaumento no índice de aderência celular nos grupos experimentais de 30 Hz e 50 Hz na técnica de Schliephake e ao CM de 60 Hz em relação aocontrole (p<0,05). A atividade fagocítica diminuiu apenas nos grupos de 30 Hz e 50 Hz na técnica de Schliephake e ao CM de 60 Hz em relação aocontrole (p<0,05). Assim, a DOCP de 30 Hz e 50 Hz na técnica de Schliephake e o CM aumentaram o índice de aderência e diminuíram aatividade fagocítica, o que pode ter aplicações em processos traumáticosagudos. Como macrófagos de animais desnutridos e recuperados mostraram responder a essas irradiações, e como estas são largamente utilizadas em fisioterapia, esses achados auxiliarão na escolha da modulação da DOCP durante o procedimento terapêutico, particularmente em casos que tenham sofrido desnutrição pregressa.In view of the established relationships between neonatal malnutrition and the immuno system, peritoneal macrophages of male Wistar rats were exposed to diatermic pulsate short waves (DPSW) and to alternated magnetic field on extreme low frequency, in order to verify in vitro adhesion index and phagocytic activity. The rats were submitted to malnutrition during the nursing period and to a recovery diet after weaning. The extracted peritoneal macrophages were exposed to DPSWmodulated at 30 Hz, 50 Hz and 430 Hz by using the Schliephake andconventional techniques in parallel, and to a magnetic filed of 60 Hz. Results show increased adhesion index only with the 30 Hz and 50 Hzexperimental groups using Schliephake technique and C M 60 Hz; phagocytic activity was reduced with 30 Hz and 50 Hz using Schliephaketechnique and C M 60 Hz, as compared to the control group (p<0,05).Since macrophages of malnourished and recovered animals responded to such irradiations, and since these are largely used in physical therapy, present results could be used to choose correct DPSW modulation in therapeutic process, particularly in cases who have previously suffered malnutrition
Cardiovascular diseases and air pollution in Novi Sad, Serbia
Objectives: A large body of evidence has documented that air pollutants have adverse effect on human health as well as on the environment. The aim of this study was to determine whether there was an association between outdoor concentrations of sulfur dioxide (SO2) and nitrogen dioxide (NO2) and a daily number of hospital admissions due to cardiovascular diseases (CVD) in Novi Sad, Serbia among patients aged above 18. Material and Methods: The investigation was carried out during over a 3-year period (from January 1, 2007 to December 31, 2009) in the area of Novi Sad. The number (N = 10 469) of daily CVD (ICD-10: I00-I99) hospital admissions was collected according to patients' addresses. Daily mean levels of NO2 and SO2, measured in the ambient air of Novi Sad via a network of fixed samplers, have been used to put forward outdoor air pollution. Associations between air pollutants and hospital admissions were firstly analyzed by the use of the linear regression in a single polluted model, and then trough a single and multi-polluted adjusted generalized linear Poisson model. Results: The single polluted model (without confounding factors) indicated that there was a linear increase in the number of hospital admissions due to CVD in relation to the linear increase in concentrations of SO2 (p = 0.015; 95% confidence interval (95% CI): 0.144-1.329, R2 = 0.005) and NO2 (p = 0.007; 95% CI: 0.214-1.361, R2 = 0.007). However, the single and multi-polluted adjusted models revealed that only NO2 was associated with the CVD (p = 0.016, relative risk (RR) = 1.049, 95% CI: 1.009-1.091 and p = 0.022, RR = 1.047, 95% CI: 1.007-1.089, respectively). Conclusions: This study shows a significant positive association between hospital admissions due to CVD and outdoor NO2 concentrations in the area of Novi Sad, Serbia
Satisfação dos usuários com a assistência de saúde no estado de Pernambuco, Brasil, 2005
SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal
Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by
the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration
with more than 50 laboratories distributed nationwide.
Methods By applying recent phylodynamic models that allow integration of individual-based
travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal.
Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from
European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland),
which were consistent with the countries with the highest connectivity with Portugal.
Although most introductions were estimated to have occurred during early March 2020, it is
likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the
first cases were confirmed.
Conclusions Here we conclude that the earlier implementation of measures could have
minimized the number of introductions and subsequent virus expansion in Portugal. This
study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and
Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with
the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team,
IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation
(https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing
guidance on the implementation of the phylodynamic models; Joshua L. Cherry
(National Center for Biotechnology Information, National Library of Medicine, National
Institutes of Health) for providing guidance with the subsampling strategies; and all
authors, originating and submitting laboratories who have contributed genome data on
GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions
expressed in this article are those of the authors and do not reflect the view of the
National Institutes of Health, the Department of Health and Human Services, or the
United States government. This study is co-funded by Fundação para a Ciência e Tecnologia
and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on
behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study
come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by
COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation
(POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal
Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL
2020 Partnership Agreement, through the European Regional Development Fund
(ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio
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