Search results for " population growth"
showing 7 items of 27 documents
Seasonal cardenolide production and Dop5βr gene expression in natural populations of Digitalis obscura
2004
Productivity variations and seasonal fluctuations of cardenolides have been studied in 10 natural populations of Digitalis obscura distributed in three bioclimatic belts. Main cardenolides in D. obscura plants are those of the series A and such predominance (ca. 80-85%) over the series B metabolites is independent of the population studied or the degree of maturity of the leaves. Primary glycosides represent ca. 50-60% of total cardenolides; this percentage did not vary among populations or with the leaf age but increased in summer and decreased in winter. A correlation analysis between plant biomass and cardenolide content showed a positive relationship of these parameters, which, accordin…
Identification of Traits Implicated in the Rhizosphere Competence of Fluorescent Pseudomonads: Description of a Strategy Based on Population and Mode…
2009
E-book; International audience; The lack of consistency of the beneficial effects of inoculated fluorescent pseudomonads has often been related to their bad survival in the rhizosphere. In this review, we describe the strategy followed over the last decade to study traits involved in the rhizosphere competence of these bacteria. The diversity of indigenous populations associated with plant roots was first compared to that of populations associated with uncultivated soils in order to identify traits that discriminate these populations. The involvement of these bacterial traits in the rhizosphere competence was then assessed by comparing the competitiveness of a wild-type strain to that of mu…
A Bayesian Reconstruction of a Historical Population in Finland, 1647–1850
2020
This article provides a novel method for estimating historical population development. We review the previous literature on historical population time-series estimates and propose a general outline to address the well-known methodological problems. We use a Bayesian hierarchical time-series model that allows us to integrate the parish-level data set and prior population information in a coherent manner. The procedure provides us with model-based posterior intervals for the final population estimates. We demonstrate its applicability by estimating the long-term development of Finlands population from 1647 onward and simultaneously place the country among the very few to have an annual popula…
Cardenolide variation within and among natural populations of Digitalis obscura
1999
Summary Cardenolide content in 49 wild-growing Digitalis obscura plants from six natural populations on the Iberian Peninsula was determined by HPLC. Series A and B glycosides were the predominant cardenolides in all samples, but absolute values varied among and within populations. Hierarchic analysis of variance showed that the proportion of variation attributable to individuals was significantly higher than that attributable to population differences. Furthermore, analyses from greenhouse-grown plants, generated from seeds collected from selected parental genotypes, attributed nearly all the variability in cardenolide content to single plants. Some individual plants showed a leaf content …
Effects of air pollution on dementia over Europe for present and future climate change scenarios.
2020
The scientific literature is scarce when referring to the influence of atmospheric pollutants on neurodegenerative diseases for present and future climate change scenarios. In this sense, this contribution evaluates the incidence of dementia (Alzheimer's disease, AD, and dementia from unspecified cause, DU) occurring in Europe associated with the exposure to air pollution (essentially NO2 and PM2.5) for the present climatic period (1991-2010) and for a future climate change scenario (RCP8.5, 2031-2050). The GEMM methodology has been applied to air pollution simulations using the chemistry/climate regional model WRF-Chem. Present population data were obtained from NASA's Center for Socioecon…
Variation of Terpenoids Constituents in Natural Population ofCinnamomum tamala(L.) Leaves
2009
Abstract The leaves of Cinnamomum tamala L. (Lauraceae) were collected from seven plants occurring in seven different areas of Manipur and analyzed for their essential oil and eugenol contents using GC and GC/MS. The yield of the oil was found to vary from 1.5–5.6% (w/w), on a dry weight basis. A total of 79 compounds were identified in the oils. Eugenol was found as a major compound in the leaf oils and its concentration varied from 35.1–94.3% followed by α-phellandrene (1.0–25.4%).
Empirical links between natural mortality and recovery in marine fishes
2017
Probability of species recovery is thought to be correlated with specific aspects of organismal life history, such as age at maturity and longevity, and how these affect rates of natural mortality ( M ) and maximum per capita population growth ( r max ). Despite strong theoretical underpinnings, these correlates have been based on predicted rather than realized population trajectories following threat mitigation. Here, we examine the level of empirical support for postulated links between a suite of life-history traits (related to maturity, age, size and growth) and recovery in marine fishes. Following threat mitigation (medium time since cessation of overfishing = 20 years), 71% of 55 tem…