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1.
Oecologia ; 199(3): 649-659, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35833986

RESUMO

We sought to understand the role that water availability (expressed as an aridity index) plays in determining regional and global patterns of richness and evenness, and in turn how these water availability-diversity relationships may result in different richness-evenness relationships at regional and global scales. We examined relationships between water availability, richness and evenness for eight grassy biomes spanning broad water availability gradients on five continents. Our study found that relationships between richness and water availability switched from positive for drier (South Africa, Tibet and USA) vs. negative for wetter (India) biomes, though were not significant for the remaining biomes. In contrast, only the India biome showed a significant relationship between water availability and evenness, which was negative. Globally, the richness-water availability relationship was hump-shaped, however, not significant for evenness. At the regional scale, a positive richness-evenness relationship was found for grassy biomes in India and Inner Mongolia, China. In contrast, this relationship was weakly concave-up globally. These results suggest that different, independent factors are determining patterns of species richness and evenness in grassy biomes, resulting in differing richness-evenness relationships at regional and global scales. As a consequence, richness and evenness may respond very differently across spatial gradients to anthropogenic changes, such as climate change.


Assuntos
Biodiversidade , Poaceae , China , Ecossistema , Água
2.
Artigo em Inglês | MEDLINE | ID: mdl-34886035

RESUMO

The South-to-North Water Diversion (SNWD) provides significant benefits in facilitating water security and improving ecology in northern China. However, few studies have estimated the water value of the SNWD and the corresponding subsequent subsidies of the ecological migrants in Xichuan County displaced by the project. Based on the Google Earth Engine (GEE), this study analyzed the water ecosystem changes in Xichuan County in 2000-2020 and valued the water transfer of the SNWD. We calculated the water cost, the water value of the trunk line project, and the four provinces (Hebei, Henan, Beijing, and Tianjin) of CNY 4.04, 39.64, and 120.93 billion, respectively, and the proportion of the three was 1:10:30 during 2014-2020. The water ecosystem area showed a rapid increase when the SNWD became operational since the end of 2014. The subsequent annual subsidy gap of ecological migrants was CNY 0.84 billion, which only accounted for 4.31% of the gross profit of SNWD. Our results imply that relevant water sectors have sufficient profits to support corresponding subsequent subsidies for ecological migrants. Ecological migrants are a major challenge for water transfer projects. Overall, this study fills a gap of interactions between subsequent policies and ecological migrants and provides a typical case for managing the migration problem caused by sustainable water management worldwide.


Assuntos
Ecossistema , Água , China , Conservação dos Recursos Naturais , Planeta Terra
3.
Sci Data ; 7(1): 327, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020494

RESUMO

We present the MARAS (Environmental Monitoring of Arid and Semiarid Regions) dataset, which stores vegetation and soil data of 426 rangeland monitoring plots installed throughout Patagonia, a 624.500 km2 area of southern Argentina and Chile. Data for each monitoring plot includes basic climatic and landscape features, photographs, 500 point intercepts for vegetation cover, plant species list and biodiversity indexes, 50-m line-intercept transect for vegetation spatial pattern analysis, land function indexes drawn from 11 measures of soil surface characteristics and laboratory soil analysis (pH, conductivity, organic matter, N and texture). Monitoring plots were installed between 2007 and 2019, and are being reassessed at 5-year intervals (247 have been surveyed twice). The MARAS dataset provides a baseline from which to evaluate the impacts of climate change and changes in land use intensity in Patagonian ecosystems, which collectively constitute one of the world´s largest rangeland areas. This dataset will be of interest to scientists exploring key ecological questions such as biodiversity-ecosystem functioning relationships, plant-soil interactions and climatic controls on ecosystem structure and functioning.

4.
Rev Esp Cardiol (Engl Ed) ; 71(11): 910-916, 2018 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29764762

RESUMO

INTRODUCTION AND OBJECTIVES: New biomarkers could improve the predictive capacity of classic risk functions. The aims of this study were to determine the association between circulating levels of apolipoprotein A1 (apoA1), apolipoprotein B (apoB), albumin, and 25-OH-vitamin D and coronary events and to analyze whether these biomarkers improve the predictive capacity of the Framingham-REGICOR risk function. METHODS: A case-cohort study was designed. From an initial cohort of 5404 individuals aged 35 to 74 years with a 5-year follow-up, all the participants who had a coronary event (n = 117) and a random group of the cohort (subcohort; n = 667) were selected. Finally, 105 cases and 651 individuals representative of the cohort with an available biological sample were included. The events of interest were angina, fatal and nonfatal myocardial infarction and coronary deaths. RESULTS: Case participants were older, had a higher proportion of men and cardiovascular risk factors, and showed higher levels of apoB and lower levels of apoA1, apoA1/apoB ratio, 25-OH-vitamin D and albumin than the subcohort. In multivariate analyses, plasma albumin concentration was the only biomarker independently associated with coronary events (HR, 0.73; P = .002). The inclusion of albumin in the risk function properly reclassified a significant proportion of individuals, especially in the intermediate risk group (net reclassification improvement, 32.3; P = .048). CONCLUSIONS: Plasma albumin levels are inversely associated with coronary risk and improve the predictive capacity of classic risk functions.


Assuntos
Apolipoproteínas A/sangue , Apolipoproteínas B/sangue , Doença da Artéria Coronariana/sangue , Albumina Sérica/metabolismo , Vitamina D/sangue , Adulto , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia
5.
Rev Esp Cardiol (Engl Ed) ; 71(9): 718-725, 2018 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29174866

RESUMO

INTRODUCTION AND OBJECTIVES: Our aims were to determine acute myocardial infarction (AMI) incidence and mortality rates, and population and in-hospital case-fatality in the population older than 74 years; variability in clinical characteristics and AMI management of hospitalized patients, and changes in the incidence and mortality rates, case-fatality, and management by age groups from 1996 to 1997 and 2007 to 2008. METHODS: A population-based AMI registry in Girona (Catalonia, Spain) including individuals with suspected AMI older than 34 years. RESULTS: The incidence rate increased with age from 169 and 28 cases/100 000 per year in the group aged 35 to 64 years to 2306 and 1384 cases/100 000 per year in the group aged 85 to 94 years, in men and women, respectively. Population case-fatality also increased with age, from 19% in the group aged 35 to 64 years to 84% in the group aged 85 to 94 years. A lower population case-fatality was observed in the second period, mainly explained by a lower in-hospital case-fatality. The use of invasive procedures and effective drugs decreased with age but increased in the second period in all ages up to 84 years. CONCLUSIONS: Acute myocardial infarction incidence, mortality, and case-fatality increased exponentially with age. There is still a gap in the use of invasive procedures and effective drugs between younger and older patients.


Assuntos
Infarto do Miocárdio/epidemiologia , Vigilância da População , Sistema de Registros , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Causas de Morte/tendências , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Fatores Sexuais , Espanha/epidemiologia , Taxa de Sobrevida/tendências , Fatores de Tempo
6.
Rev. educ. fis ; 26(3): 465-472, jul.-set. 2015. tab
Artigo em Português | LILACS | ID: lil-767217

RESUMO

RESUMO Os objetivos do estudo foram elaborar referências e analisar as características da composição corporal de atletas adolescentes de pentatlo moderno nos sexos feminino e masculino, por meio do DXA, em diferentes fases da puberdade. Participaram 48 atletas adolescentes praticantes de pentatlo moderno, sendo 21 meninas (14,67±2,35) e 27 meninos (15,15±1,51 anos). Em atletas do sexo feminino o percentual de gordura foi considerado alto no grupo de púberes; o aumento da massa magra e a estabilidade da gordura corporal, em púberes avançados e pós-púberes, são efeitos decorrentes dos efeitos do treinamento de pentatlo moderno. Os atletas masculinos apresentaram alterações comuns na composição corporal durante todas as fases da puberdade. A avaliação do BMC e BMD parecem pertinentes as adolescentes na mesma fase da puberdade praticantes de outras modalidades esportivas no masculino e feminino, demonstrando impacto positivo do treinamento.


ABSTRACT The aims of the study were to elaborate references and analyze the characteristics of body composition of adolescent modern pentathlon athletes in female and male, through DXA at different pubertal stages . A total of 48 adolescent athletes practitioners of modern pentathlon, 21 girls (14.67 ± 2.35) and 27 boys (15.15 ± 1.51 years). In female athletes the percentage of fat was considered high in pubescent group; increased lean body mass and the stability of body fat in advanced pubescent and post-pubescent, are effects of the practice of modern pentathlon training. Male athletes showed changes in body composition that are common during the puberty. The evaluation of BMC and BMD in male and female seem appropriate to adolescents at the same stage of puberty practitioners of other sports, demonstrating the positive impact of the training.

8.
Biol Lett ; 10(10): 20140673, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25339654

RESUMO

Drought is an increasingly common phenomenon in drylands as a consequence of climate change. We used 311 sites across a broad range of environmental conditions in Patagonian rangelands to evaluate how drought severity and temperature (abiotic factors) and vegetation structure (biotic factors) modulate the impact of a drought event on the annual integral of normalized difference vegetation index (NDVI-I), our surrogate of ecosystem functioning. We found that NDVI-I decreases were larger with both increasing drought severity and temperature. Plant species richness (SR) and shrub cover (SC) attenuated the effects of drought on NDVI-I. Grass cover did not affect the impacts of drought on NDVI-I. Our results suggest that warming and species loss, two important imprints of global environmental change, could increase the vulnerability of Patagonian ecosystems to drought. Therefore, maintaining SR through appropriate grazing management can attenuate the adverse effects of climate change on ecosystem functioning.


Assuntos
Biodiversidade , Secas , Ecossistema , Plantas , Temperatura , Argentina , Clima , Poaceae
10.
Rev Esp Cardiol ; 59(11): 1106-12, 2006 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-17144985

RESUMO

INTRODUCTION AND OBJECTIVES: The natural history of idiopathic atrial fibrillation is not well understood. The aim of this study was to investigate the frequency of and risk factors for disease recurrence. METHODS: The study involved 115 patients with a first episode of paroxysmal atrial fibrillation of unknown origin who were included the FAP registry, which contains data from 11 district hospitals in Catalonia, Spain. All patients underwent comprehensive clinical, laboratory, electro-cardiographic and echocardiographic investigations at baseline and were followed up periodically every 6 months to identify the occurrence of new symptomatic episodes and their complications. RESULTS: During a mean follow-up period of 912 (445) days, 32 (27.8%) patients experienced recurrence of atrial fibrillation. Those who experienced recurrence had a significantly higher left ventricular ejection fraction (P=.023) and smaller end-systolic volume (P<.001), and they were more likely to consume alcohol regularly (P=.013). Cox regression analysis confirmed that these variables had independent prognostic value. In contrast, the occurrence of syncope during the initial episode was associated with a lower likelihood of recurrence (P=.017). CONCLUSIONS: The risk of recurrence of idiopathic atrial fibrillation was high, and was enhanced by moderate alcohol consumption and increased left ventricular activity, probably of sympathetic origin. This trend was less marked in paroxysmal atrial fibrillation of vagal origin.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Sistema de Registros , Fatores de Risco
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