Base de dados : MEDLINE
Pesquisa : G16.500.275.071.387 [Categoria DeCS]
Referências encontradas : 204 [refinar]
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  1 / 204 MEDLINE  
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[PMID]:29293693
[Au] Autor:Tovar C; Sánchez Infantas E; Teixeira Roth V
[Ad] Endereço:Departamento de Biología, Facultad de Ciencias, Universidad Nacional Agraria La Molina, Av. La Molina s/n, Lima, Peru.
[Ti] Título:Plant community dynamics of lomas fog oasis of Central Peru after the extreme precipitation caused by the 1997-98 El Niño event.
[So] Source:PLoS One;13(1):e0190572, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Despite El Niño events being one of the main forces shaping the coastal desert vegetation in South America, the impacts of the high precipitation typical of this rare but recurrent climatic event remain understudied. Here we monitored the plant community of a coastal lomas, a seasonal desert ecosystem, during 1998 and 2001 to analyse its changes during the 1997-98 El Niño and the following La Niña events. We measured species abundance and vegetation cover in 31 plots, and recorded climate variables in Lomas de Lachay, Peru. We found a significant positive correlation between precipitation and vegetation cover, density, alpha diversity (species diversity at the plot level), total richness and abundance of several key species but no correlation with gamma diversity (species diversity at the whole loma level). During the El Niño event, the seasonality, typical of the lomas ecosystem, disappeared, as evidenced by both the similarity of species composition and mean vegetation cover values between most sampling campaigns of 1998 and 1999. Moreover, total richness was lower during the El Niño event than during the humid season of 2000 and 2001 resulting from the dominance of only a few species, such as Nicotiana paniculata and Loasa urens. Temporal-spatial changes in the abundance of the dominant species caused the differences between alpha and gamma diversity, especially during 1999. Within that year, mean alpha diversity showed similar values whilst gamma diversity values were different. The reestablishment of the seasonality of most plant community characteristics and a clear difference between species composition of the humid and the dry season occurred two years after the El Niño event, suggesting a resilient community. This study provides one of the few quantifications of the Peruvian lomas' response to the 1997-98 El Niño event and the following La Niña, one of the most extreme climatic events in the last century.
[Mh] Termos MeSH primário: El Niño Oscilação Sul
Chuvas
Tempo (Meteorologia)
[Mh] Termos MeSH secundário: Biodiversidade
Clima
Ecossistema
Peru
Plantas/classificação
Estações do Ano
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190572


  2 / 204 MEDLINE  
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[PMID]:29342148
[Au] Autor:Zhao H; Zhao J; Sun X; Chen F; Han G
[Ad] Endereço:Guangdong Ocean University, Zhanjiang, China.
[Ti] Título:A strong summer phytoplankton bloom southeast of Vietnam in 2007, a transitional year from El Niño to La Niña.
[So] Source:PLoS One;13(1):e0189926, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Summer upwelling occurs frequently off the southeast Vietnam coast in the western South China Sea (SCS), where summer phytoplankton blooms generally appear during June-August. In this study, we investigate inter-annual variation of Ekman pumping and offshore transport, and its modulation on summer blooms southeast of Vietnam. The results indicate that there are low intensities of summer blooms in El Niño years, under higher sea surface temperatures (SST) and weaker winds. However, a different pattern of monthly chlorophyll a (Chl-a) blooms occurred in summer of 2007, a transitional stage from El Niño to La Niña, with weak (strong) wind and high (low) SST before (after) early July. There is a weak phytoplankton bloom before July 2007 and a strong phytoplankton bloom after July 2007. The abrupt change in the wind intensity may enhance the upwelling associated with Ekman pumping and offshore Ekman transport, bringing more high-nutrient water into the upper layer from the subsurface, and thus leading to an evident Chl-a bloom in the region.
[Mh] Termos MeSH primário: El Niño Oscilação Sul
Fitoplâncton/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Estações do Ano
Vietnã
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180118
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189926


  3 / 204 MEDLINE  
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[PMID]:29200423
[Au] Autor:Tang X; Zhao S; Chiu APY; Wang X; Yang L; He D
[Ad] Endereço:Shenzhen Center for Disease Control and Prevention, Shenzhen, China.
[Ti] Título:Analysing increasing trends of Guillain-Barré Syndrome (GBS) and dengue cases in Hong Kong using meteorological data.
[So] Source:PLoS One;12(12):e0187830, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Guillain-Barré Syndrome (GBS) is a severe paralytic neuropathy associated with virus infections such as Zika virus and Chikungunya virus. There were also case reports of dengue fever preceding GBS. With the aim to understand the mechanisms of GBS and dengue outbreaks, this ecological study investigates the relationships between GBS, dengue, meteorological factors in Hong Kong and global climatic factors from January 2000 to June 2016. METHODS: The correlations between GBS, dengue, Multivariate El Niño Southern Oscillation Index (MEI) and local meteorological data were explored by Spearman's Rank correlations and cross-correlations. Three Poisson regression models were fitted to identify non-linear associations among GBS, dengue and MEI. Cross wavelet analyses were applied to infer potential non-stationary oscillating associations among GBS, dengue and MEI. FINDINGS AND CONCLUSION: We report a substantial increasing of local GBS and dengue cases (mainly imported) in recent year in Hong Kong. The seasonalities of GBS and dengue are different, in particular, GBS is low while dengue is high in the summer. We found weak but significant correlations between GBS and local meteorological factors. MEI could explain over 17% of dengue's variations based on Poisson regression analyses. We report a possible non-stationary oscillating association between dengue fever and GBS cases in Hong Kong. This study has led to an improved understanding about the timing and ecological relationships between MEI, GBS and dengue.
[Mh] Termos MeSH primário: Temperatura Baixa/efeitos adversos
Dengue/epidemiologia
Surtos de Doenças
El Niño Oscilação Sul
Síndrome de Guillain-Barré/epidemiologia
[Mh] Termos MeSH secundário: Vírus Chikungunya/isolamento & purificação
Dengue/complicações
Vírus da Dengue/isolamento & purificação
Síndrome de Guillain-Barré/virologia
Hong Kong/epidemiologia
Seres Humanos
Estações do Ano
Luz Solar
Zika virus/isolamento & purificação
Infecção pelo Zika virus/epidemiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171229
[Lr] Data última revisão:
171229
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0187830


  4 / 204 MEDLINE  
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[PMID]:28450208
[Au] Autor:Laureano-Rosario AE; Garcia-Rejon JE; Gomez-Carro S; Farfan-Ale JA; Muller-Karger FE
[Ad] Endereço:Institute for Marine Remote Sensing, University of South Florida, College of Marine Science, 140 7th Avenue South, Saint Petersburg, FL 33701, USA. Electronic address: elias3@mail.usf.edu.
[Ti] Título:Modelling dengue fever risk in the State of Yucatan, Mexico using regional-scale satellite-derived sea surface temperature.
[So] Source:Acta Trop;172:50-57, 2017 Aug.
[Is] ISSN:1873-6254
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Accurately predicting vector-borne diseases, such as dengue fever, is essential for communities worldwide. Changes in environmental parameters such as precipitation, air temperature, and humidity are known to influence dengue fever dynamics. Furthermore, previous studies have shown how oceanographic variables, such as El Niño Southern Oscillation (ENSO)-related sea surface temperature from the Pacific Ocean, influences dengue fever in the Americas. However, literature is lacking on the use of regional-scale satellite-derived sea surface temperature (SST) to assess its relationship with dengue fever in coastal areas. Data on confirmed dengue cases, demographics, precipitation, and air temperature were collected. Incidence of weekly dengue cases was examined. Stepwise multiple regression analyses (AIC model selection) were used to assess which environmental variables best explained increased dengue incidence rates. SST, minimum air temperature, precipitation, and humidity substantially explained 42% of the observed variation (r =0.42). Infectious diseases are characterized by the influence of past cases on current cases and results show that previous dengue cases alone explained 89% of the variation. Ordinary least-squares analyses showed a positive trend of 0.20±0.03°C in SST from 2006 to 2015. An important element of this study is to help develop strategic recommendations for public health officials in Mexico by providing a simple early warning capability for dengue incidence.
[Mh] Termos MeSH primário: Dengue/epidemiologia
Modelos Teóricos
Oceanos e Mares
Temperatura Ambiente
[Mh] Termos MeSH secundário: Américas
El Niño Oscilação Sul
Seres Humanos
Umidade
Incidência
México/epidemiologia
Risco
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE


  5 / 204 MEDLINE  
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[PMID]:29036207
[Au] Autor:Loisel J; MacDonald GM; Thomson MJ
[Ad] Endereço:Department of Geography, Texas A&M University, Eller O&M Building, College Station TX.
[Ti] Título:Little Ice Age climatic erraticism as an analogue for future enhanced hydroclimatic variability across the American Southwest.
[So] Source:PLoS One;12(10):e0186282, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The American Southwest has experienced a series of severe droughts interspersed with strong wet episodes over the past decades, prompting questions about future climate patterns and potential intensification of weather disruptions under warming conditions. Here we show that interannual hydroclimatic variability in this region has displayed a significant level of non-stationarity over the past millennium. Our tree ring-based analysis of past drought indicates that the Little Ice Age (LIA) experienced high interannual hydroclimatic variability, similar to projections for the 21st century. This is contrary to the Medieval Climate Anomaly (MCA), which had reduced variability and therefore may be misleading as an analog for 21st century warming, notwithstanding its warm (and arid) conditions. Given past non-stationarity, and particularly erratic LIA, a 'warm LIA' climate scenario for the coming century that combines high precipitation variability (similar to LIA conditions) with warm and dry conditions (similar to MCA conditions) represents a plausible situation that is supported by recent climate simulations. Our comparison of tree ring-based drought analysis and records from the tropical Pacific Ocean suggests that changing variability in El Niño Southern Oscillation (ENSO) explains much of the contrasting variances between the MCA and LIA conditions across the American Southwest. Greater ENSO variability for the 21st century could be induced by a decrease in meridional sea surface temperature gradient caused by increased greenhouse gas concentration, as shown by several recent climate modeling experiments. Overall, these results coupled with the paleo-record suggests that using the erratic LIA conditions as benchmarks for past hydroclimatic variability can be useful for developing future water-resource management and drought and flood hazard mitigation strategies in the Southwest.
[Mh] Termos MeSH primário: Mudança Climática
Modelos Teóricos
Água
[Mh] Termos MeSH secundário: Simulação por Computador
Secas
El Niño Oscilação Sul
Previsões
Fósseis/anatomia & histologia
Sudoeste dos Estados Unidos
Temperatura Ambiente
Árvores/anatomia & histologia
Árvores/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
059QF0KO0R (Water)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171017
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186282


  6 / 204 MEDLINE  
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[PMID]:28777801
[Au] Autor:Beier E; Bernal G; Ruiz-Ochoa M; Barton ED
[Ad] Endereço:Centro de Investigación Científica y de Educación Superior de Ensenada-Unidad La Paz, La Paz, Baja California Sur, México.
[Ti] Título:Freshwater exchanges and surface salinity in the Colombian basin, Caribbean Sea.
[So] Source:PLoS One;12(8):e0182116, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Despite the heavy regional rainfall and considerable discharge of many rivers into the Colombian Basin, there have been few detailed studies about the dilution of Caribbean Surface Water and the variability of salinity in the southwestern Caribbean. An analysis of the precipitation, evaporation and runoff in relation to the climate variability demonstrates that although the salt balance in the Colombian Basin overall is in equilibrium, the area south of 12°N is an important dilution sub-basin. In the southwest of the basin, in the region of the Panama-Colombia Gyre, Caribbean Sea Water is diluted by precipitation and runoff year round, while in the northeast, off La Guajira, its salinity increases from December to May by upwelling. At the interannual scale, continental runoff is related to El Niño Southern Oscillation, and precipitation and evaporation south of 12°N are related to the Caribbean Low Level Jet. During El Niño years the maximum salinification occurs in the dry season (December-February) while in La Niña years the maximum dilution (or freshening), reaching La Guajira Coastal Zone, occurs in the wet season (September-November).
[Mh] Termos MeSH primário: Monitoramento Ambiental
Água Doce/química
Rios/química
Salinidade
[Mh] Termos MeSH secundário: Região do Caribe
El Niño Oscilação Sul
Panamá
Estações do Ano
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182116


  7 / 204 MEDLINE  
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[PMID]:28671858
[Au] Autor:Flores-Morán A; Banuet-Martínez M; Elorriaga-Verplancken FR; García-Ortuño LE; Sandoval-Sierra J; Acevedo-Whitehouse K
[Ti] Título:Atypical Red Blood Cells Are Prevalent in California Sea Lion Pups Born during Anomalous Sea Surface Temperature Events.
[So] Source:Physiol Biochem Zool;90(5):564-574, 2017 Sep/Oct.
[Is] ISSN:1537-5293
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To date, there is limited knowledge of the effects that abnormal sea surface temperature (SST) can have on the physiology of neonate pinnipeds. However, maternal nutritional deficiencies driven by alimentary restrictions would expectedly impact pinniped development and fitness, as an adequate supply of nutrients is essential for growth and proper functioning of all body systems, including red blood cell synthesis and clearance. Here, we investigated red blood cell morphology of California sea lion (CSL) pups from the San Benito Archipelago born during the 2014 and 2015 anomalously high SST events recorded in the northeastern Pacific Ocean. We examined whether atypical erythrocyte morphologies were more common in 2015, when the high SST event was more pronounced, and whether the stable isotope signature of pup fur, as an indicator of maternal feeding strategies, accounted for the number of atypical cells. Various atypical erythrocyte morphologies were more prevalent and more abundant than reference values. Evidence of iron deficiency was found in both years, and only pups born in 2014 showed evidence of active erythropoiesis. Microcytes and reticulocytes were more common in pups with higher isotopic δ C and lower δ N values, suggesting a probable relationship between maternal feeding strategies and the effect of climatic anomalies on red blood cell physiology of their pups. As developing pinnipeds require increased oxygen storage capacity for diving and foraging, the presence of atypical erythrocytes could be relevant to CSL pup fitness if the underlying cause is not reverted. This study is a first step to explore the effects that climatic alterations in the marine environment can have on the blood physiology of developing individuals.
[Mh] Termos MeSH primário: El Niño Oscilação Sul
Eritrócitos Anormais
Leões-Marinhos/sangue
[Mh] Termos MeSH secundário: Envelhecimento
Animais
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170927
[Lr] Data última revisão:
170927
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170704
[St] Status:MEDLINE
[do] DOI:10.1086/692919


  8 / 204 MEDLINE  
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[PMID]:28594886
[Au] Autor:Gutierrez L
[Ad] Endereço:Affiliation Department of Agricultural Sciences and Desertification Research Centre, University of Sassari, Sassari, Italy.
[Ti] Título:Impacts of El Niño-Southern Oscillation on the wheat market: A global dynamic analysis.
[So] Source:PLoS One;12(6):e0179086, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Although the widespread influence of the El Niño-Southern Oscillation (ENSO) occurrences on crop yields of the main agricultural commodities is well known, the global socio-economic consequences of ENSO still remain uncertain. Given the global importance of wheat for global consumption by providing 20% of global calories and nourishment, the monitoring and prediction of ENSO-induced variations in the worldwide wheat market are essential for allowing national governments to manage the associated risks and to ensure the supplies of wheat for consumers, including the underprivileged. To this end, we propose a global dynamic model for the analysis of ENSO impacts on wheat yield anomalies, export prices, exports and stock-to-use ratios. Our framework focuses on seven countries/regions: the six main wheat-exporting countries-the United States, Argentina, Australia, Canada, the EU, and the group of the main Black Sea export countries, i.e. Russia, Ukraine, and Kazakhstan-plus the rest of the world. The study shows that La Niña exerts, on average, a stronger and negative impact on wheat yield anomalies, exports and stock-to-use ratios than El Niño. In contrast, wheat export prices are positively related to La Niña occurrences evidencing, once again, its steady impact in both the short and long run. Our findings emphasize the importance of the two ENSO extreme phases for the worldwide wheat market.
[Mh] Termos MeSH primário: El Niño Oscilação Sul
Internacionalidade
Marketing
Triticum/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Comércio/economia
Modelos Teóricos
Análise Multivariada
Oceanos e Mares
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170609
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179086


  9 / 204 MEDLINE  
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[PMID]:28447651
[Au] Autor:Fraser B
[Ti] Título:Surprise El Niño causes devastation but offers lessons for ecologists.
[So] Source:Nature;544(7651):405-406, 2017 04 25.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Mh] Termos MeSH primário: Clima Desértico
Planejamento em Desastres/tendências
Desastres
Ecossistema
El Niño Oscilação Sul/efeitos adversos
Inundações
Chuvas
[Mh] Termos MeSH secundário: Animais
Produtos Agrícolas/crescimento & desenvolvimento
Planejamento em Desastres/economia
Desastres/prevenção & controle
Ecologia/economia
Ecologia/tendências
Inundações/mortalidade
Cadeia Alimentar
Florestas
Seres Humanos
Meteorologia/economia
Meteorologia/tendências
Peru
Rios/química
[Pt] Tipo de publicação:NEWS
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170428
[St] Status:MEDLINE
[do] DOI:10.1038/544405a


  10 / 204 MEDLINE  
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[PMID]:28445534
[Au] Autor:Donner SD; Rickbeil GJM; Heron SF
[Ad] Endereço:Department of Geography, University of British Columbia, Vancouver, British Columbia, Canada.
[Ti] Título:A new, high-resolution global mass coral bleaching database.
[So] Source:PLoS One;12(4):e0175490, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Episodes of mass coral bleaching have been reported in recent decades and have raised concerns about the future of coral reefs on a warming planet. Despite the efforts to enhance and coordinate coral reef monitoring within and across countries, our knowledge of the geographic extent of mass coral bleaching over the past few decades is incomplete. Existing databases, like ReefBase, are limited by the voluntary nature of contributions, geographical biases in data collection, and the variations in the spatial scale of bleaching reports. In this study, we have developed the first-ever gridded, global-scale historical coral bleaching database. First, we conducted a targeted search for bleaching reports not included in ReefBase by personally contacting scientists and divers conducting monitoring in under-reported locations and by extracting data from the literature. This search increased the number of observed bleaching reports by 79%, from 4146 to 7429. Second, we employed spatial interpolation techniques to develop annual 0.04° × 0.04° latitude-longitude global maps of the probability that bleaching occurred for 1985 through 2010. Initial results indicate that the area of coral reefs with a more likely than not (>50%) or likely (>66%) probability of bleaching was eight times higher in the second half of the assessed time period, after the 1997/1998 El Niño. The results also indicate that annual maximum Degree Heating Weeks, a measure of thermal stress, for coral reefs with a high probability of bleaching increased over time. The database will help the scientific community more accurately assess the change in the frequency of mass coral bleaching events, validate methods of predicting mass coral bleaching, and test whether coral reefs are adjusting to rising ocean temperatures.
[Mh] Termos MeSH primário: Antozoários/fisiologia
Recifes de Corais
Bases de Dados Factuais
[Mh] Termos MeSH secundário: Animais
Ecossistema
El Niño Oscilação Sul
Aquecimento Global
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170427
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0175490



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