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1.
Glob Chang Biol ; 24(2): e496-e510, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28906052

RESUMO

Net Primary Productivity (NPP) is one of the most important parameters in describing the functioning of any ecosystem and yet it arguably remains a poorly quantified and understood component of carbon cycling in tropical forests, especially outside of the Americas. We provide the first comprehensive analysis of NPP and its carbon allocation to woody, canopy and root growth components at contrasting lowland West African forests spanning a rainfall gradient. Using a standardized methodology to study evergreen (EF), semi-deciduous (SDF), dry forests (DF) and woody savanna (WS), we find that (i) climate is more closely related with above and belowground C stocks than with NPP (ii) total NPP is highest in the SDF site, then the EF followed by the DF and WS and that (iii) different forest types have distinct carbon allocation patterns whereby SDF allocate in excess of 50% to canopy production and the DF and WS sites allocate 40%-50% to woody production. Furthermore, we find that (iv) compared with canopy and root growth rates the woody growth rate of these forests is a poor proxy for their overall productivity and that (v) residence time is the primary driver in the productivity-allocation-turnover chain for the observed spatial differences in woody, leaf and root biomass across the rainfall gradient. Through a systematic assessment of forest productivity we demonstrate the importance of directly measuring the main components of above and belowground NPP and encourage the establishment of more permanent carbon intensive monitoring plots across the tropics.


Assuntos
Biomassa , Florestas , Árvores/crescimento & desenvolvimento , Clima Tropical , África Ocidental , Ciclo do Carbono , Chuva , Madeira
2.
Sci Total Environ ; 830: 154662, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35318060

RESUMO

The measures taken to contain the spread of COVID-19 in 2020 included restrictions of people's mobility and reductions in economic activities. These drastic changes in daily life, enforced through national lockdowns, led to abrupt reductions of anthropogenic CO2 emissions in urbanized areas all over the world. To examine the effect of social restrictions on local emissions of CO2, we analysed district level CO2 fluxes measured by the eddy-covariance technique from 13 stations in 11 European cities. The data span several years before the pandemic until October 2020 (six months after the pandemic began in Europe). All sites showed a reduction in CO2 emissions during the national lockdowns. The magnitude of these reductions varies in time and space, from city to city as well as between different areas of the same city. We found that, during the first lockdowns, urban CO2 emissions were cut with respect to the same period in previous years by 5% to 87% across the analysed districts, mainly as a result of limitations on mobility. However, as the restrictions were lifted in the following months, emissions quickly rebounded to their pre-COVID levels in the majority of sites.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , COVID-19/epidemiologia , Dióxido de Carbono/análise , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , SARS-CoV-2
3.
J Cardiovasc Med (Hagerstown) ; 22(12): 939-945, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34261081

RESUMO

AIM: To evaluated echocardiographic aspects in women with history of preeclampsia or preeclampsia-related complications in their previous pregnancies. MATERIALS AND METHODS: Consecutive women receiving echocardiography during daily clinical echolab activity were studied using complete echocardiographic examination data and anamnestic data collection of hypertension, diabetes, dyslipidemia, and rheumatic diseases. Studied women should have at least one pregnancy in more than the 10 past years, and were subdivided into two groups according to the history of complicated or physiological pregnancy. Complicated pregnancies were defined by preeclampsia or preeclampsia-related complication, such as preterm delivery or small-for-gestational age newborn. Echocardiographic parameters and prevalence of hypertension, diabetes, dyslipidemia, and rheumatic disease were compared between the two groups of studied women. RESULTS: From March 2016 to May 2020, 545 women were studied, of whom 218 had a history of complicated pregnancy (mean age 60.81 ±â€Š11.109 years vs. 62.78 ±â€Š9.758 years of not complicated pregnancy; P = 0.03). Compared with physiological pregnancy women, complicated pregnancy ones were shorter (159.97 ±â€Š6.608 vs. 161.42 ±â€Š6.427 cm; P = 0.012) with lower body surface area (1.678 ±â€Š0.1937 vs. 1.715 ±â€Š0.1662 m2; P = 0.02), had higher prevalence of diabetes (6.9 vs. 3.1%; P = 0.04; odds ratio = 2.34; CI 1.0323--5.3148) and rheumatic diseases (33 vs. 22.3%; P = 0.006; odds ratio = 1.72; CI 1.1688--2.5191), and showed a slight, not significant higher prevalence of hypertension. As for echocardiographic parameters, they showed significantly higher values of end-diastolic left ventricular posterior wall (LPWd) (P = 0.034), a trend toward a more concentric geometry, and a worse longitudinal systolic left and right ventricle performance, represented by lower tissue Doppler systolic waves (septal: 7.41 ±â€Š1.255 vs. 7.69 ±â€Š1.376 cm/s; P = 0.018; and tricuspidalic: 12.64 ±â€Š2.377 vs. 13.32 ±â€Š2.548 cm/s; P = 0.003). CONCLUSION: Patients with previous preeclampsia present an increased risk of hypertension, diabetes, and rheumatic diseases, suggesting that these women could share a specific predisposition to a high-risk profile. Furthermore, they show a higher prevalence of classically considered echocardiographic hypertensive-derived cardiac damage, suggesting structural and functional left ventricular modifications as subclinical aspects of long-term worse cardiovascular prognosis for these women.


Assuntos
Diabetes Mellitus/epidemiologia , Ecocardiografia , Ventrículos do Coração/patologia , Hipertensão/epidemiologia , Doenças Reumáticas/epidemiologia , Disfunção Ventricular Direita , Estudos Transversais , Ecocardiografia/métodos , Ecocardiografia/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Itália/epidemiologia , Pessoa de Meia-Idade , Trabalho de Parto Prematuro/epidemiologia , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Gravidez , Prognóstico , História Reprodutiva , Medição de Risco/métodos , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/epidemiologia
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