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1.
Proc Biol Sci ; 290(2001): 20230344, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37357858

RESUMO

Ecological theory posits that temporal stability patterns in plant populations are associated with differences in species' ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, especially across different biomes. We compiled a worldwide collection of long-term permanent vegetation records (greater than 7000 plots from 78 datasets) from a large range of habitats which we combined with existing trait databases. We tested whether the observed inter-annual variability in species abundance (coefficient of variation) was related to multiple individual traits. We found that populations with greater leaf dry matter content and seed mass were more stable over time. Despite the variability explained by these traits being low, their effect was consistent across different datasets. Other traits played a significant, albeit weaker, role in species stability, and the inclusion of multi-variate axes or phylogeny did not substantially modify nor improve predictions. These results provide empirical evidence and highlight the relevance of specific ecological trade-offs, i.e. in different resource-use and dispersal strategies, for plant populations stability across multiple biomes. Further research is, however, necessary to integrate and evaluate the role of other specific traits, often not available in databases, and intraspecific trait variability in modulating species stability.


Assuntos
Ecossistema , Plantas , Filogenia , Sementes , Fenótipo , Folhas de Planta
2.
Proc Natl Acad Sci U S A ; 117(39): 24345-24351, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32900958

RESUMO

The stability of ecological communities is critical for the stable provisioning of ecosystem services, such as food and forage production, carbon sequestration, and soil fertility. Greater biodiversity is expected to enhance stability across years by decreasing synchrony among species, but the drivers of stability in nature remain poorly resolved. Our analysis of time series from 79 datasets across the world showed that stability was associated more strongly with the degree of synchrony among dominant species than with species richness. The relatively weak influence of species richness is consistent with theory predicting that the effect of richness on stability weakens when synchrony is higher than expected under random fluctuations, which was the case in most communities. Land management, nutrient addition, and climate change treatments had relatively weak and varying effects on stability, modifying how species richness, synchrony, and stability interact. Our results demonstrate the prevalence of biotic drivers on ecosystem stability, with the potential for environmental drivers to alter the intricate relationship among richness, synchrony, and stability.


Assuntos
Plantas/classificação , Sequestro de Carbono , Mudança Climática , Ecossistema , Desenvolvimento Vegetal , Plantas/metabolismo , Solo/química
3.
J Cardiovasc Nurs ; 35(2): 210-216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31904694

RESUMO

BACKGROUND: Clustering of cardiovascular risk factors (CVRFs) is extraordinarily common and is associated with an increased risk of cardiovascular disease (CVD). However, the particular impact of the sum of CVRFs on cardiovascular morbidity and mortality has not been sufficiently explored in Europe. OBJECTIVE: The aim of this study was to analyze the differences in survival-free probability of CVD in relation to the number of CVRFs in a Spanish population. METHODS: A prospective cohort study was conducted from 1992 to 2016 in a Spanish population that included 1144 subjects with no history of CVD (mean age, 46.7 years) drawn from the general population. We calculated the number of CVRFs for each subject (male sex, smoking, diabetes, hypertension, dyslipidemia, obesity, and left ventricular hypertrophy). Cardiovascular morbidity and mortality records were collected, and survival analysis was applied (competing risk models). RESULTS: There were 196 cardiovascular events (17.1%). The differences in total survival-free probability of cardiovascular morbidity and mortality of the different values of the sum of CVRFs were significant, increasing the risk of CVD (hazard ratio, 1.30; 95% confidence interval, 1.13-1.50) per each additional risk factor. CONCLUSION: Differences in survival-free probability of CVD in relation to the number of CVRFs present were statistically significant. Further studies are needed to corroborate our results.


Assuntos
Doenças Cardiovasculares/epidemiologia , Fatores de Risco de Doenças Cardíacas , Adulto , Análise por Conglomerados , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
4.
Ecol Lett ; 22(8): 1297-1305, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31190431

RESUMO

Zoogeographical regions, or zooregions, are areas of the Earth defined by species pools that reflect ecological, historical and evolutionary processes acting over millions of years. Consequently, researchers have assumed that zooregions are robust and unlikely to change on a human timescale. However, the increasing number of human-mediated introductions and extinctions can challenge this assumption. By delineating zooregions with a network-based algorithm, here we show that introductions and extinctions are altering the zooregions we know today. Introductions are homogenising the Eurasian and African mammal zooregions and also triggering less intuitive effects in birds and amphibians, such as dividing and redefining zooregions representing the Old and New World. Furthermore, these Old and New World amphibian zooregions are no longer detected when considering introductions plus extinctions of the most threatened species. Our findings highlight the profound and far-reaching impact of human activity and call for identifying and protecting the uniqueness of biotic assemblages.


Assuntos
Anfíbios , Aves , Espécies em Perigo de Extinção , Atividades Humanas , Animais , Biodiversidade , Conservação dos Recursos Naturais , Extinção Biológica , Humanos , Mamíferos
5.
J Cardiovasc Nurs ; 33(6): E17-E23, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30273261

RESUMO

BACKGROUND: Although studies exist comparing low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (HDL-C) in the development of cardiovascular disease (CVD), most have limitations in the mathematical models used to evaluate their prognostic power adjusted for the other risk factors (cardiovascular risk). OBJECTIVE: The aim of this study was to compare LDL-C and non-HDL-C in patients with CVD to determine whether both parameters predict CVD similarly. METHODS: A cohort of 1322 subjects drawn from the general population of a Spanish region was followed between 1992 and 2006. The outcome was time to CVD. Secondary variables were gender, age, hypertension, diabetes, personal history of CVD, current smoker, body mass index, LDL-C, and non-HDL-C. Two CVD prediction models were constructed with the secondary variables, with only the lipid parameter varying (non-HDL-C or LDL-C). In the construction of the models, the following were considered: multiple imputation, events per variable of 10 or more, and continuous predictors as powers. The validation was conducted by bootstrapping obtaining the distribution of the C statistic (discrimination) and the probabilities observed by smooth curves. These results were compared in both models using graphical and analytical testing. RESULTS: There were a total of 137 CVD events. The models showed no differences in the distributions of the C statistic (discrimination, P = .536) or in the calibration plot. CONCLUSIONS: In our population, LDL-C and non-HDL-C were equivalent at predicting CVD. More studies using this methodology are needed to confirm these results.


Assuntos
Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Valor Preditivo dos Testes , Medição de Risco/métodos
6.
Children (Basel) ; 11(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38255432

RESUMO

Currently, the use of digital tools has led to significant changes in the educational system, favouring equity and the inclusion of students with educational needs. In this context, students with autism spectrum disorder (ASD) benefit from using these electronic devices to improve their learning experience. This study focuses on conducting a bibliometric analysis of the impact of information and communication technologies on the learning of students with ASD, with the aim of addressing two research questions. Through the analysis of three databases (Scopus, Dialnet, and Web of Science), a total of 24 articles related to the subject were collected. The results show that the use of different technological devices has numerous benefits for these students. Among the most prominent are the use of augmented reality and educational robotics, mainly providing improvements in academic performance, motivation and improved retention of knowledge acquired in the classroom. In conclusion, the clear need to train teachers in digital competencies and to intensify efforts in this line of research in order to improve the education of students, as well as to enrich the knowledge available to the scientific community, is highlighted.

7.
Oecologia ; 172(2): 449-59, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23090759

RESUMO

Vertebrate herbivores can be key determinants of grassland plant species richness, although the magnitude of their effects can largely depend on ecosystem and herbivore characteristics. It has been demonstrated that the combined effect of primary productivity and body size is critical when assessing the impact of herbivores on plant richness of perennial-dominated grasslands; however, the interaction of site productivity and herbivore size as determinants of plant richness in annual-dominated pastures remains unknown. We experimentally partitioned primary productivity and herbivore body size (sheep and wild rabbits) to study the effect of herbivores on the plant species richness of a Mediterranean semiarid annual plant community in central Spain over six years. We also analyzed the effect of grazing and productivity on the evenness and species composition of the plant community, and green cover, litter, and plant height. We found that plant richness was higher where the large herbivore was present at high-productivity sites but barely changed at low productivity. The small herbivore did not affect species richness at either productivity site despite its large effects on species composition. We propose that adaptations to resource scarcity and herbivory prevented plant richness changes at low-productivity sites, whereas litter accumulation in the absence of herbivores decreased plant richness at high productivity. Our results are consistent with predictions arising from a long history of grazing and highlight the importance of both large and small herbivores to the maintenance of plant diversity of Mediterranean annual-dominated pastures.


Assuntos
Biodiversidade , Tamanho Corporal , Herbivoria/fisiologia , Poaceae , Coelhos , Ovinos , Animais , Ecossistema , Espanha
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 293: 122450, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36753918

RESUMO

Composting olive mill pomace (OMP), the major by-product of the olive oil industry, is an attractive waste management practice in the context of sustainable food production. Thermal treatment of compost at mild temperatures (torrefaction) can aid to improve its characteristics as a soil amendment. This study aims to understand the chemical changes occurring during torrefaction of olive mill pomace-based (OMP) compost, as well as to evaluate the treatment effects on compost at different stages of maturation. Here, treatments at different temperatures (175, 225, and 275 °C) and duration (from 1 to 5 h) have been employed to obtain a sort of torrefied samples. In general, the H/C and O/C atomic ratios of compost samples decreased with torrefaction temperatures, which suggests an incipient coalification of the organic matter. Furthermore, the results showed that a combination of FT-NIR and FT-MIR spectroscopy using a low-level data fusion strategy is very sensitive to the molecular changes occurring both in the composting process and during heating. Principal Component Analysis (PCA) of the merged spectra revealed that the changes at 175 °C are mainly the loss of water (O-H contributions at 3300 and 5169 cm-1) together with the degradation of proteins (observed in the decrease of amide I and II characteristic bands). Furthermore, the samples heated at this temperature can still be differentiated by their initial maturation stage. On the other hand, thermochemical changes occurring at higher temperatures are more intense and make the samples more alike, independently of the composting time. When heating above 225 °C, the loss of O-H happens together with the decrease of aliphatic moieties, reflected in the bands 2920 and 2850 cm-1 (FT-MIR) and 4258, 4323, 5665, and 5781 cm-1 (FT-MIR). This can be attributed to the thermal degradation of cellulosic materials and, additionally, to the degradation of the residual oil in the case of poorly composted samples. Heated samples are characterized by the presence of carbonyl groups (1709 cm-1) and humic-like complex and polymerized aromatic structures (1579 cm-1). Since the characteristics of the torrefied compost at 275 °C are very similar regardless of the initial maturation stage, torrefaction may be a very interesting way to reduce the composting time of olive mill pomace to obtain a high-quality organic amendment for soil application.


Assuntos
Compostagem , Olea , Olea/química , Quimiometria , Resíduos Industriais/análise , Solo/química , Espectrofotometria Infravermelho
9.
Artigo em Inglês | MEDLINE | ID: mdl-36767938

RESUMO

Higher education institutions moving towards the inclusive education model have to offer quality education for all students. In this sense, the use of technologies favours not only the education of people with disabilities, but also their quality of life. However, these people may encounter real problems of access to technologies due, among other factors, to the lack of teacher training, causing a public health problem. In this line, our study includes a systematic review of the literature that aims to know the impact of the technological training of university teachers in relation to educational inclusion and the improvement of the quality of life of students with disabilities. To this end, a search of the literature published in the last decade was carried out in six databases (Dialnet, Google Scholar, Scopus, Web of Science, ERIC, and SciELO), selecting 14 articles out of 1204 initial ones. The studies were analysed following the PRISMA methodology. The main findings are the scarcity of research literature on the digital competence of university teachers and its impact on the educational inclusion and quality of life of students with disabilities. Likewise, there is a clear lack of knowledge about the use of digital tools and a lack of knowledge about the different disabilities that teachers may encounter in higher education classrooms.


Assuntos
Pessoas com Deficiência , Capacitação de Professores , Humanos , Qualidade de Vida , Universidades , Estudantes
10.
Hypertension ; 80(11): 2485-2493, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694400

RESUMO

BACKGROUND: Guidelines recommend pharmacological treatment for systolic blood pressure (SBP) of 130 to 139 mm Hg in secondary prevention. However, uncertainty persists in primary prevention in low cardiovascular risk patients (CVR). METHODS: Cohort study representative of the general population of Albacete/Southeast Spain. We examined 1029 participants with untreated blood pressure and free of cardiovascular disease, followed-up during 1992 to 2019. Cox regression modeled the association of SBP with cardiovascular morbidity and mortality (outcome-1) and cardiovascular morbidity and all-cause mortality (outcome-2). RESULTS: Participants' mean age was 44.8 years (53.8%, women; 77.1% at low-CVR); 20.3% had SBP 120 to 129; 13.0% 130 to 139 at low-CVR and 3.4% at high-CVR; and 27.4% ≥140 mm Hg. After a 25.7-year median follow-up, 218 outcome-1 and 302 outcome-2 cases occurred. Unadjusted hazard ratios of outcome-1 for these increasing SBP categories (versus <120) were 2.72, 2.27, 11.54, and 7.52, respectively; and 2.69, 2.32, 10.55, and 7.34 for outcome-2 (all P<0.01). After adjustment for other risk factors, hazard ratio (95% CI) of outcome-1 were 1.49 (0.91-2.44), 1.65 (0.94-2.91, P=0.08), 1.36 (0.72-2.57), and 1.82 (1.15-2.88), respectively, and 1.39 (0.91-2.11), 1.69 (1.05-2.73), 1.09 (0.63-1.88), and 1.64 (1.11-2.41) for outcome-2. Compared with 130 to 139 at low-CVR, hazard ratio for 130 to 139 at high-CVR was 4.85 for outcome-1 (P<0.001) and 4.43 for outcome-2 (P<0.001). CONCLUSIONS: In this primary prevention population of relatively young average age, untreated SBP of 130 to 139 mm Hg at low-CVR had long-term prognostic value and might benefit from stricter SBP targets. High-CVR patients had nonsignificant higher risk (limited sample size) but 4-fold greater risk when compared with low-CVR. Overall, results indicate the importance of risk stratification, supporting risk-based decision-making.


Assuntos
Doenças Cardiovasculares , Hipertensão , Humanos , Feminino , Adulto , Masculino , Pressão Sanguínea/fisiologia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/complicações , Estudos de Coortes , Estudos Prospectivos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/complicações , Prognóstico , Fatores de Risco
11.
Commun Biol ; 6(1): 47, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639596

RESUMO

Previous attempts to quantify tree abundance at global scale have largely neglected the role of local competition in modulating the influence of climate and soils on tree density. Here, we evaluated whether mean tree size in the world's natural forests alters the effect of global productivity on tree density. In doing so, we gathered a vast set of forest inventories including >3000 sampling plots from 23 well-conserved areas worldwide to encompass (as much as possible) the main forest biomes on Earth. We evidence that latitudinal productivity patterns of tree density become evident as large trees become dominant. Global estimates of tree abundance should, therefore, consider dependencies of latitudinal sources of variability on local biotic influences to avoid underestimating the number of trees on Earth and to properly evaluate the functional and social consequences.


Assuntos
Florestas , Árvores , Ecossistema , Clima , Mudança Climática
12.
Artigo em Inglês | MEDLINE | ID: mdl-36231217

RESUMO

Access to university is a right for all people; however, access to higher education for people with disabilities is still a challenge. The present study, based on a systematic review of the literature, aims to report on the challenges faced by students with disabilities in accessing and participating in higher education. The systematic review of four databases resulted in 20 studies published between 2011 and 2021. The results indicate that students with disabilities face numerous challenges in accessing university education. Based on the results, strategies are proposed in order to provide equal opportunities and success in higher education for students with disabilities.


Assuntos
Pessoas com Deficiência , Escolaridade , Humanos , Estudantes , Revisões Sistemáticas como Assunto , Universidades
13.
Heliyon ; 8(8): e10139, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35965985

RESUMO

The COVID-19 pandemic caused changes in higher education institutions, mainly due to the temporary closure of face-to-face activities in universities worldwide. The transformation from face-to-face to online education was one of the emerging solutions to this crisis. This research aims to analyse and describe the adaptation process from face-to-face to online education and the perceptions of faculty and students during the pandemic in a literature review study. We developed this study following the methodology supported by the PRISMA statement and the PICoS strategy, retrieving scientific literature from Web of Science, Scopus, ERIC and PsycINFO. Of the 241 studies that the search yielded, 29 have been included. The results showed that online education was an enabling alternative for the development of higher education, but numerous weaknesses in the transition to online education were identified. The study concludes that online learning is a future direction in higher education. Therefore, institutions should invest more in online education platforms and improve faculty training plans.

14.
Foods ; 10(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401573

RESUMO

There is a growing interest of researchers in meat authentication in terms of geographical and dietary background of animals, and several analytical methods have been proposed for the purpose of investigating this. We hypothesized that the odd- and branched-chain fatty acid (OBCFA) profile in intramuscular fat (IMF) might suffice to distinguish lamb meat entering the food chain supply on the basis of the type of diet fed to lambs during the fattening period. A total of 30 individual OBCFA profiles, quantified by gas chromatography, of IMF of Manchego lambs were used. During the fattening period (42 days), the lambs were fed three diets differing in concentrate composition: (i) Control, concentrate typical of commercial fattening rations, rich in starch and based on cereals and soybean meal; (ii) Camelina, similar to Control but replacing 50% of the soybean meal with camelina meal; and (iii) Fibrous, concentrate rich in neutral detergent fiber (NDF), based on fibrous by-products and not including cereals nor soybean meal. The OBCFA were grouped into three classes (linear odd, iso and anteiso fatty acids) and were then submitted to a linear discriminant analysis, using the feeding treatments as grouping variable and the OBCFA class contents in IMF as quantitative variables. The results suggested that a high NDF to starch ratio of the concentrate, being the lowest for Control (CON) treatment and the highest for Fibrous (FIB) treatment, would be negatively related to the odd/anteiso ratio and positively related to the iso/(anteiso+odd) FA ratio in IMF. Determination of OBCFA profile in lamb meat would be useful to monitor the feeding regime (starch- or NDF-rich) of lambs entering the food chain supply.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33440738

RESUMO

Educational technology has become an increasingly important element for improving the teaching and learning process of students. To achieve these goals, it is essential that teachers have the skills they need to be able to introduce technology into their teaching practice. However, this is often overwhelming and stressful for many of them. The aim of this review was to find out how research on teacher stress and anxiety associated with the use of educational technology was proceeding. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines through the following bibliographic databases: PubMed, Web of Science, and Scopus. Sixteen articles were found from the review. The main findings show that teachers present high levels of anxiety or stress due to their use of educational technology in the classroom. Among the conclusions, the need for research on different strategies to prevent the emergence of these anxiety and stress symptoms in teachers stands out.


Assuntos
Transtornos de Ansiedade , Ansiedade , Tecnologia Educacional , Humanos , Aprendizagem , Estudantes
16.
Nat Commun ; 11(1): 5635, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159062

RESUMO

More tree species can increase the carbon storage capacity of forests (here referred to as the more species hypothesis) through increased tree productivity and tree abundance resulting from complementarity, but they can also be the consequence of increased tree abundance through increased available energy (more individuals hypothesis). To test these two contrasting hypotheses, we analyse the most plausible pathways in the richness-abundance relationship and its stability along global climatic gradients. We show that positive effect of species richness on tree abundance only prevails in eight of the twenty-three forest regions considered in this study. In the other forest regions, any benefit from having more species is just as likely (9 regions) or even less likely (6 regions) than the effects of having more individuals. We demonstrate that diversity effects prevail in the most productive environments, and abundance effects become dominant towards the most limiting conditions. These findings can contribute to refining cost-effective mitigation strategies based on fostering carbon storage through increased tree diversity. Specifically, in less productive environments, mitigation measures should promote abundance of locally adapted and stress tolerant tree species instead of increasing species richness.


Assuntos
Clima , Ecossistema , Árvores/crescimento & desenvolvimento , Biodiversidade , Carbono/metabolismo , Florestas , Árvores/classificação , Árvores/metabolismo
17.
Oecologia ; 159(3): 617-26, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19101733

RESUMO

Recent studies addressing broad-scale species richness gradients have proposed two main primary drivers: contemporary climate and evolutionary processes (differential balance between speciation and extinction). Here, we analyze the global richness patterns of two venomous snake clades, Viperidae and Elapidae. We used ordinary least squares multiple regression (OLS) and partial regression analysis to investigate to what extent actual evapotranspiration (AET; summarizing current environmental conditions) and biogeographical regions (representing evolutionary effects) were associated with species richness. For viperids, AET explained 45.6% of the variance in richness whereas the effect of this variable for elapids was almost null (0.5%). On the other hand, biogeographic regions were the best predictors of elapid richness (56.5%), against its relatively small effect (25.9%) in viperid richness. Partial regressions also revealed similar patterns for independent effects of climate and history in both clades. However, the independent historical effect in Elapidae decreased from 45.2 to 17.8% when we excluded Australia from the analyses, indicating that the strong historical effect that had emerged for the global richness pattern was reflecting the historical process of elapid radiation into Australia. Even after excluding Australia, the historical signal in elapid richness in the rest of the globe was still significant and much higher than that observed in viperid richness at a global scale (2.7% after controlling for AET effects). Differences in the evolutionary age of these two clades can be invoked to explain these contrasting results, in that viperids probably had more time for diversification, generating richness responses to environmental gradients, whereas the pattern of distribution of elapid richness can be more directly interpreted in an evolutionary context. Moreover, these results show the importance of starting to adopt deconstructive approaches to species richness, since the driving factors of these patterns may vary from group to group according to their evolutionary history.


Assuntos
Ecologia , Elapidae/classificação , Viperidae/classificação , Animais , Evolução Biológica , Especificidade da Espécie
19.
Clin Investig Arterioscler ; 30(2): 64-71, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29395492

RESUMO

INTRODUCTION: Non-HDL cholesterol (non-HDL-C) is becoming relevant both in its participation in cardiovascular risk assessment and as a therapeutic target. The objective of the present study was to assess the independent predictive capacity of both non-HDL-C and LDL-C (the main priority in dyslipidemias to reduce cardiovascular risk), in cardiovascular morbidity in a population-based sample. METHODS: A prospective cohort study involving 1186 individuals in the non-HDL-C group and 1177 in the LDL-C group, followed for 10.7years (SD=2.2), who had not had any previous cardiovascular event. The predictor variables included in the adjustment were: gender, age, arterial hypertension, diabetes mellitus, smoker status and non-HDL-C in one group. In the other group, consisting of patients presenting TG levels of 400mg/dL, non-HDL-C was replaced by LDL-C. Survival curves (Kaplan-Meier) were calculated and two Cox regression models were applied, one for each group. RESULTS: Non-HDL-C group presented 6.2% of non-fatal cardiovascular episodes during follow-up and the LDL-C group 6.0%. After adjustment, for each 30mg/dL increase in non-HDL-C, the incidence of new non-fatal cardiovascular events increased by 31% (HR=1.31, 95%CI: 1.06-1.61; P=.018) and in the LDL-C group by 27% (HR=1.27, 95%CI: 0.97-1.61, P=.068). CONCLUSIONS: After a follow-up of 10.7years, non-HDL-C has been shown in our population as a prognostic factor of non-fatal cardiovascular disease, but not LDL-C, although its HR is close to statistical significance.


Assuntos
Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/sangue , Colesterol/sangue , Dislipidemias/complicações , Adulto , Idoso , Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , Estudos de Coortes , Dislipidemias/sangue , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Triglicerídeos/sangue
20.
Ecol Evol ; 7(18): 7548-7559, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28944038

RESUMO

Understanding how environmental change alters the composition of plant assemblages, and how this in turn affects ecosystem functioning is a major challenge in the face of global climate change. Assuming that values of plant traits express species adaptations to the environment, the trait-based approach is a promising way to achieve this goal. Nevertheless, how functional traits are related to species' environmental tolerances and how trait spectra respond to broad-scale environmental gradients remains largely unexplored. Here, we identify the main trait spectra for US angiosperm trees by testing hypotheses for the relationships between functional traits and species' environmental tolerances to environmental stresses, as well as quantifying the environmental drivers of assemblage means and variances of these traits. We analyzed >74,000 community assemblages from the US Forest Inventory and Analysis using 12 functional traits, five traits expressing species' environmental tolerances and 10 environmental variables. Results indicated that leaf traits, dispersal traits, and traits related to stem hydraulics were related to cold or drought tolerance, and their assemblage means were best explained by minimum temperatures. Assemblage means of traits related to shade tolerance (tree growth rate, leaf phosphorus content, and bark thickness) were best explained by aridity index. Surprisingly, aridity index, rather than minimum temperature, was the best predictors of assemblage variances of most traits, although these relationships were variable and weak overall. We conclude that temperature is likely to be the most important driver of functional community structure of North American angiosperm trees by selecting for optimum strategies along the cold and drought stress trade-off. In turn, water availability primarily affects traits related to shade tolerance through its effect on forest canopy structure and vegetation openness.

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