Results Consistent with previous research we find a positive association between cumulative residential mobility and cannabis use with conventional logistic regression models (Odds Ratio: 2.56, 95% Confidence Interval: 1.20-5.78), implying that adolescents who experience a residential change are more likely to use cannabis than those who remain residentially stable. However, decomposing this relationship into its between- and within-child components reveals that a conventional model is underspecified and misleading; we find that differences in cannabis use between mobile and non-mobile adolescents are due to underlying selection differences between these groups (between-child log odds: 3.56, standard error: 1.22), not by a change in status of residential mobility (within-child log odds: 1.33, standard error: 1.02). ...
Work looking at the interplay between residential mobility, deprivation, age, personal socioeconomic circumstance, and health outcomes.
Depro, B., & Timmins, C. (2012). Residential mobility and ozone exposure: Challenges for environmental justice policy. In The Political economy of environmental justice (pp. 145 - 188). (The Political Economy of Environmental Justice). Palo Alto, CA: Stanford University Press. ...
article{9837a013-2002-40ce-93f0-0bf266da9173, abstract = {Within the paradigm of population dynamics a central task is to identify environmental factors affecting population change and to estimate the strength of these effects. We here investigate the impact of observation errors in measurements of population densities on estimates of environmental effects. Adding observation errors may change the autocorrelation of a population time series with potential consequences for estimates of effects of autocorrelated environmental covariates. Using Monte Carlo simulations, we compare the performance of maximum likelihood estimates from three stochastic versions of the Gompertz model (log-linear first order autoregressive model), assuming 1) process error only, 2) observation error only, and 3) both process and observation error (the linear state-space model on log-scale). We also simulated population dynamics using the Ricker model, and evaluated the corresponding maximum likelihood estimates for ...
Demographic transition from primitive population stability to modern population stability is happening in developed countries There is need to ensure that this transition happens in developing countries also Primitive population stability of high birth rates were offset by high infant and childhood mortality has transitioned to a modern population stability of low infant and childhood mortality are balanced by low birth rates Epidemiologic transition: During primitive population stability CDR was high (,40) - receding fatal diseases, epidemics and famines reduced CDR to ~11 - now most people in developed countries die from cancer, cardiovascular diseases and other degenerative diseases Fertility transition: CBR in the developed countries declined from a high of 40-50 during primitive population stability to 8-12 of the modern population stability due to industrialization, economic development and social modernization Economic development and social modernization has been observed to bring about ...
The way that mothers provision their offspring can have important consequences for their offsprings performance throughout life. Models suggest that maternally induced variation in life histories may have large population dynamical effects, even perhaps driving cycles such as those seen in forest Lepidoptera. The evidence for large maternal influences on population dynamics is unconvincing, principally because of the difficulty of conducting experiments at both the individual and population level. In the soil mite, Sancassania berlesei, we show that there is a trade-off between a females fecundity and the per-egg provisioning of protein. The mothers position on this trade-off depends on her current food availability and her age. Populations initiated with 250 eggs of different mean sizes showed significant differences in the population dynamics, converging only after three generations. Differences in the growth, maturation and fecundity of the initial cohort caused differences in the ...
This 2015 OECD Economic Survey of Belgium examines recent economic developments, policies and prospects. Special chapters cover integration of immigrants and the housing sector.. ...
By David Baker and William Smith[1] Widespread formal education is shaping population dynamics globally. From new trends in mortality and health disparities in the United States to demographic and epidemiological population transitions in less developed nations, access to schooling is proving to be one of demographys most potent causal factors. Research has repeatedly found education…
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
ABSTRACT: In marine systems, empirical studies demonstrating effects of macroparasites on host population dynamics are relatively few. We tested the effects of a copepod macroparasite infecting the gills of a small coral reef fish, the bridled goby Coryphopterus glaucofraenum. Fish that were naturally infected and uninfected were tagged as individuals and tracked in the field for 5 mo. Parasitism was associated with an increase in gill ventilation rate, and a reduction in feeding. More importantly, parasitized fish showed significantly reduced growth (by 66%) and gonad mass (by 68%) compared to uninfected fish, and parasitism increased instantaneous mortality by a factor of 1.8. Since the prevalence of infection was higher in areas of high goby density, parasite-induced mortality is a possible cause of host density dependence. These results imply a major effect of parasitism on host population dynamics and suggest that parasitism warrants closer attention by marine ecologists. ...
A no-frills group of wildlife enthusiasts, scientists, photographers and local residents wishing to see wild boar and all other wildlife thrive in the Forest of Dean and elsewhere in the UK. Founded by David J Slater and Joyce Moss in the summer of 2011 as an independent conservation group with no prior affiliations. Hoping to promote understanding of wild boar and as a pressure group to produce a realistic and science-based management plan of wild boar in the UK. E-mail us via "my complete profile" below. Media enquirers only - please telephone 07999950697 ...
Like predation and competition, mutualism is now recognized as a consumer resource (C-R) interaction, including, in particular, bi-directional (e.g., coral, plant- mycorrhizae) and uni-directional (e.g., ant-plant defense, plant-pollinator) C-R mutualisms. Here, we develop general theory for the density-dependent population dynamics of mutualism based on the C-R mechanism of interspecific interaction. To test the influence of C-R interactions on the dynamics and stability of bi- and uni-directional C-R mutualisms, we developed simple models that link consumer functional response of one mutualistic species with the resources supplied by another. Phase-plane analyses show that the ecological dynamics of C-R mutualisms are stable in general. Most transient behavior leads to an equilibrium of mutualistic coexistence, at which both species densities are greater than in the absence of interactions. However, due to the basic nature of C-R interactions, certain density-dependent conditions can lead to C-R
1. Metapopulation microcosms were constructed to test the effect of four different types of habitat heterogeneity on the dynamics and dispersal in spatially extended systems; homogeneity, spatial heterogeneity, temporal heterogeneity and spatio-temporal heterogeneity. Resources were distributed across discrete habitat patches in bruchid beetle (Callosobruchus maculatus) metapopulations, and long-term time series were recorded. 2. Mathematical models were fitted to the long-term time series from the experimental systems using a maximum likelihood approach. Models were composed of separate birth, death, emigration and immigration terms all of which incorporated stochasticity drawn from different probability distributions. Models with density-dependent and density-independent birth, death and emigration terms were investigated and, in each case, the model that best described the empirical data was identified. 3. At the local scale, population sizes differed between patches depending on the type of
booktitle = "Machine Learning: {ECML} 2001, 12th European Conference on Machine Learning, Freiburg, Germany, September 5-7, 2001, Proceedings ...
Population dynamics result from the interplay of density-independent and density-dependent processes. Understanding this interplay is important, especially for being able to predict near-term population trajectories for management. In recent years, the study of model systems-experimental, observational and theoretical-has shed considerable light on the way that the both density-dependent and -independent aspects of the environment affect population dynamics via impacting on the organisms life history and therefore demography. These model-based approaches suggest that (i) individuals in different states differ in their demographic performance, (ii) these differences generate structure that can fluctuate independently of current total population size and so can influence the dynamics in important ways, (iii) individuals are strongly affected by both current and past environments, even when the past environments may be in previous generations and (iv) dynamics are typically complex and transient due to
My initial graduate work was on spatial population dynamics and specifically how spatial interaction fundamentally changes population dynamics and to what extent does it not fundamentally change populations dynamics. If it does fundamentally change dynamics, then how simple can that spatial model be? At what point can a uniform mixing model approximate the properties of a non-uniform mixing process? The papers "Is diffusion too simple?", "Basic epidemiological concepts in a spatial context", and "Running from trouble" were all exploring these ideas. I reviewed some of these ideas in "Partial differential equation models in ecology". Later I taught a graduate course on spatial dynamics which tried to bring all these ideas together. My post-graduate work was focused on an experimental study of metapopulation dynamics using mosquitoes. This was a huge perturbation experiment to test some ideas about how metapopulation dynamics should change in response to variability in the environment. Since 1999, ...
... is an important concept in ecology and refers to the ways in which a populations composition changes over time, both in the short-term and the long-term. Understanding the composition of a population is imperative to understanding growth trends and thus, a populations demography.. Population dynamics is not a novel term in ecology. In fact, studying population size goes far back in scientific research. Early research can be dated back to the 1600s. It was in 1662 that John Graunt was fascinated by mortality rates in Britain and made a treatise for the population of Britain to analyse what influenced the age of death.. Furthermore, population dynamics is a rather mathematical branch of ecology because it uses equations to model how a population may evolve over time. There is a simple equation which can be used to model how populations change over time. This equation considers BIDE dynamics:. Nt+1 = Nt + B + I - D - E. Variables:. Nt+1 = population size at some future ...
We conclude that the increasing spatial synchrony of metapopulation dynamics in 1993-2013 (figure 1c,d), reflected in the increasing amplitude of metapopulation fluctuations (figure 1a), is caused by increasing frequency of dry weather in July (figure 3b,c), which leads to withering of host plants and subsequent larval mortality. We discuss the effect of drought via host plant quality below, but observe meanwhile that, following a steep decline, the metapopulation is largely released from density-dependent regulatory processes (figure 3a), which has allowed rapid recovery and hence no long-term declining trend in the size of the metapopulation (figure 1a). The maximal fecundity of the Glanville fritillary is very high, as females may lay more than 1000 eggs [42], which allows, when conditions are favourable, rapid population increase. The related and biologically similar species Euphydryas aurinia used to exhibit outbreak population dynamics in the UK in the early part of the twentieth century ...
Looking for population dynamics? Find out information about population dynamics. The aggregate of processes that determine the size and composition of any population Explanation of population dynamics
Looking for Population Dynamics, Animal? Find out information about Population Dynamics, Animal. the regular patterns of change in the number of individuals in the population of a given species during the course of a year or a number of years ,... Explanation of Population Dynamics, Animal
Abstract: Abstract Background Methods for analyzing space-time variation in risk in case-control studies typically ignore residential mobility. We develop an approach for analyzing case-control data for mobile individuals and apply it to study bladder cancer in 11 counties in southeastern Michigan. At this time data collection is incomplete and no inferences should be drawn - we analyze these data to demonstrate the novel methods. Global, local and focused clustering of residential histories for 219 cases and 437 controls is quantified using time-dependent nearest neighbor relationships. Business address histories for 268 industries that release known or suspected bladder cancer carcinogens are analyzed. A logistic model accounting for smoking, gender, age, race and education specifies the probability of being a case, and is incorporated into the cluster randomization procedures. Sensitivity of clustering to definition of the proximity metric is assessed for 1 to 75 k nearest neighbors. Results ...
Extreme climatic conditions and their ecological impacts are currently emerging as critical features of climate change. We studied extreme sea ice condition (ESIC) and found it impacts both life-history traits and population dynamics of an Antarctic seabird well beyond ordinary variability. The Southern Fulmar (Fulmarus glacialoides) is an ice-dependent seabird, and individuals forage near the ice edge. During an extreme unfavorable year (when sea ice area is reduced and distance between ice edge and colony is high), observed foraging trips were greater in distance and duration. As a result, adults brought less food to their chicks, which fledged in the poorest body condition. During such unfavorable years, breeding success was extremely low and population growth rate (λ) was greatly reduced. The opposite pattern occurred during extreme favorable years. Previous breeding status had a strong influence on life-history traits and population dynamics, and their responses to extreme conditions. ...
The post-doc position is part of the NWO-VICI project Adapting to a warmer world: phenology, physiology and fitness. In this project, we study selection on phenotypic plasticity in timing of reproduction in great tits in relation to global climate change. There are five integrated subprojects ranging from quantitative genetics, population dynamics and reproductive physiology to genomics. Four of these subprojects are underway and we are now looking for a post-doctoral candidate for the fifth subproject on population dynamics. This project will be carried out in collaboration with Prof Bernt-Erik Saether (NTNU, Trondheim, Norway) and Dr Stephanie Jenouvrier (CNRS, France & WHOI, USA ...
The Brookings Center on Social and Economic Dynamics and the Metropolitan Policy Program jointly hosted an NICHD funded Agent Based Modeling and Spatial Population Dynamics Workshop at the Brookings Institution. Researchers from across the country attended the workshop to discuss current projects, to gain insight into agent-based modeling, and to unearth issues for future research collaboration.
Distinct strategies associated with colour morphs can have effects on population dynamics, and on the partitioning and population structure of genetic variation. Antagonistic interactions and hybrid incompatibilities between morphs could have negative consequences for population fitness, and its effects may be magnified in a small population. Therefore, covariation between colour and sexual, behavioural and physiological traits may be relevant to conservation management. The Gouldian finch (Erythrura gouldiae) has two sympatric head colour morphs, and with a history of population declines this species is a flagship for conservation in Northern Australia. Captive studies have shown that the sympatric colour morphs correspond to different behavioural strategies, and interbreeding between morphs leads significant offspring mortality. This selection on head colour polymorphism may be a detriment to recovery of Gouldian finch populations, and could lead to genetic substructuring with respect to ...
The three main population processes - fertility, mortality and migration - are studied by focusing on population developments in Sweden and Europe.
Population models represent an important field in Biomathematics. They give information and forecast about dynamics of the population. This talk will give an insight about population dynamics models in general and we will talk about two such models in detail. We will start with the stability analysis of the Easter Island population dynamics model than we will take a look at the numerical methods for the Lotka-Volterra system.. ...
Human activities change the natural flow regimes in streams and rivers and this impacts ecosystems. In this talk I will mathematically investigate the impact of changes in water flow on biological populations. The approach I will take is to develop process-oriented advection-diffusion-reaction equations that couple hydraulic flow to population growth, and then to analyze the equations so as to assess the effect of impacts of water flow on population dynamics. The mathematical framework is based on new theory for the net reproductive rate $R_0$ as applied to advection-diffusion-reaction equations. I will then connect the theory to populations in rivers under various flow regimes.. This work lays the groundwork for connecting $R_0$ to more complex models of spatially structured and interacting populations, as well as more detailed habitat and hydrological data. This is achieved through explicit numerical simulation of two dimensional depth-averaged models for river population dynamics.. ...
Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood. Here we build on an established two-sex model and investigate how increased susceptibility to infection in males affects the dynamics, under different mating systems. We investigate the effect of pathogenic disease at different case mortalities, under both monogamous and polygynous mating systems. If the case mortality is low, then male-biased parasitism appears similar to unbiased parasitism in terms of its effect on the population dynamics. At higher case mortalities, we identified significant differences between male-biased and unbiased parasitism. A host population may therefore be differentially affected by male-biased and unbiased parasitism. The dynamical outcome is likely to depend on a complex interaction between the hosts mating system and demography, and the parasite ...
Family risk factors such as low parental education, unemployment, adolescent parenting and residential mobility can hinder child development. Combined with poverty, the effects are more severe. When poor families face such risk factors, they are less able to get resources to mitigate the effects on their familys physical and mental health. These experiences-often referred to as adverse childhood experiences-can shape not only a childs cognitive and emotional development, but his or her long-term physical health as well. A growing body of evidence now links early-childhood adversity to increased risk of a range of adult health problems, including diabetes, hypertension, stroke, obesity and some forms of cancer. According to the National Center for Children in Poverty, children living in poverty with three or more risk factors are exceptionally vulnerable. Risk factors increase the likelihood that young children will experience high levels of stress. Frequent stress on a child, without adequate ...
View Notes - 19-ch36-populationsWES from BIOL 1334 at UT Arlington. Chapter 36 Population Dynamics wildlife day shifts Population ecology is the study of how & why populations change population
Freckleton, R.P., Gill, Jenny, Noble, D. and Watkinson, A.R. (2005) Large-scale population dynamics, abundance-occupancy relationships and the scaling from local to regional population size. Journal of Animal Ecology, 74. pp. 353-364. ISSN 1365-2656 Full text not available from this repository. (Request a copy ...
Understanding ecological and evolutionary consequences of variation in habitat quality is increasingly important as biologists seek to address human-mediated environmental change. I investigated effects of natural temperature variation on individual fitness and population dynamics of Drosophila melanogaster inhabiting rotting apples in orchards. I also examined how critical habitat designations have influenced recovery plans for threatened and endangered species.I exposed D. melanogaster to field temperatures in rotting apples and measured survivorship and development time. Extreme temperatures in sun-exposed apples reduced survivorship of D. melanogaster by more than 50% relative to that in shaded apples. This difference is comparable to that caused by seasonal changes in ambient temperature, and suggested that selection will target traits conferring greater heat resistance.I next conducted a 3 x 2 factorial experiment that revealed an interaction effect of ethanol and temperature variation ...
There is no way around demographic change: the future of many developed countries is characterized by shrinking and ageing population. This development implies many challenges for Europes urban and rural areas. Demographic change is getting on agenda of academics, policy makers and many other stakeholders. In particular, population decline is discovered as a relevant topic.. In their book*, Managing population Decline in Europes Urban and Rural Areas, Gert-Jan Hospers and Nol Reverda provide a valuable asset to the population decline discourse by discussing this phenomenon from demographical, geographical and sociological point of view. The focus of this book is on the population decline as a transformation process. More specifically they are interested in the way in which people connect with each other: in other words on the impact of this development on the social structures. Namely, so far population decline discussion has been primarily led by spatial planning and policy research. New ...
Treatment of time in fish population dynamics is flexible. By convention, stock size in number or weight Nt or Bt refers to the start (however defined) of year t. Yield Yt and catch in numbers Ct are annual sums. Recruitment Rt is usually an annual number, though it may be an annual biomass, and is typically modeled as occurring at a discrete point during the year, rather than as a continuous process. This may reflect the origin of much fish population dynamics theory in higher latitudes, where seasonality is pronounced, as are the corresponding biological processes.. Models of individual growth (see section titled Growth of individuals) are usually continuous in time, but size at age is often simplified to an annual average, rather than a continuously varying measure. In modeling mortality, instantaneous - rather than simple - rates are used, with the notable exception of some salmon models, or in simplified models written in discrete time. Reflecting the conventions above, a detailed fish ...
Matrix population models are widely used to predict population dynamics, but when applied to species-rich ecosystems with many rare species, the small population sample sizes hinder a good fit of species-specific models. This issue can be overcome by assigning species to groups to increase the size of the calibration data sets. However, the species classification is often disconnected from the matrix modelling and from the estimation of matrix parameters, thus bringing species groups that may not be optimal with respect to the predicted community dynamics ...
Australian Cake Decorating Network. buy complex population dynamics a theoreticalempirical synthesis 2003 only to control for an ACDN computer! Since 2013 we discuss started our prior buy, Cake!
Buy Complex Population Dynamics (9780691090207) (9780691090214): A Theoretical/Empirical Synthesis: NHBS - Peter Turchin, Princeton University Press
The question of how dispersal behavior is adaptive and how it responds to changes in selection pressure is more relevant than ever, as anthropogenic habitat alteration and climate change accelerate...
One new approach that is only first beginning to be explored, is that of directly assessing the field-exposed animal for its own reproductive health condition. Although researchers may be disinclined to venture outside of the laboratory and into highly variable environmental settings to conduct unusual and possibly labor-intensive work, the potential gains can far outstrip any complications. Direct health assessment for reproductive effects is predicated upon an entirely different understanding of the potential for contaminated areas to pose health risks. The new approach recognizes that at virtually all contaminated sites where reproductive and other assessments are to be made, multiple decades have elapsed since the contamination was released, and consequently tens, and in some cases hundreds, of generations of ecological species (e.g., small rodents) have already cycled through by the present day. Thus, it is really too late to be endeavoring to project or forecast the likelihood of ...
DETERMINING GENDER In general, the muscles in a man are stronger and more developed than in a woman. Bones of men are larger and more robust than bones of women. Some bones display specific features which can be used to help determination of the sex of the skeleton. The best indicators are the: - Skull - Pelvis - Head of the Femur
Addresses: van Groenendael J, Catholic Univ Nijmegen, Dept Ecol, Toernooiveld 1, NL-6525 ED Nijmegen, Netherlands. Catholic Univ Nijmegen, Dept Ecol, NL-6525 ED Nijmegen, Netherlands. Univ Stockholm, Dept Bot, SE-10691 Stockholm, Sweden. Uppsala Univ, Evo. Available from: 2008-10-17 Created: 2008-10-17 Last updated: 2017-12-06Bibliographically approved ...
Read "When does fragmentation of breeding habitat affect population survival?, Ecological Modelling" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Abstract: We explore the use of Intrinsic Dimension (ID) for gaining insights in how populations evolve in Evolutionary Algorithms. ID measures the minimum number of dimensions needed to accurately describe a dataset and its estimators are being used more and more in Machine Learning to cope with large datasets. We postulate that ID can provide information about population which is complimentary w.r.t.\ what (a simple measure of) diversity tells. We experimented with the application of ID to populations evolved with a recent variant of Grammatical Evolution. The preliminary results suggest that diversity and ID constitute two different points of view on the population dynamics ...
library(ggplot2) library(dplyr) library(magrittr) library(tidyr) data_extinct ,- readr::read_delim(data_0.09.txt, \t, escape_double = FALSE, col_names = FALSE, trim_ws = TRUE) %,% set_names(c(time, paste0(,seq(1,100,1)))) df ,- data_extinct %,% gather(key=i, value=N, -time) %,% mutate(i = as.integer(i)) %,% arrange(time, i) ggplot(df, aes(x=time, y=i, z = N))+ stat_contour(geom = polygon, aes(fill = ..level..), bins = 6000) + scale_fill_distiller(palette=Spectral, trans=log10)+ geom_contour(aes(colour = ..level..), binwidth=0.25, lwd=0.3, show.legend = F)+ scale_color_distiller(palette=Spectral, trans=log10)+ labs(x=Time, y=Position, fill=Pop. Size, caption= Diff. between 2 contours = 0.25)+ theme_bw ...
The research theme Population Dyanmics within the department of Evolutionary and Population Biology focuses on two subthemes: (i) population biology of trophic interactions in species communities and (ii) eco-evolutionary dynamics.
Vol 4: Inferences about population dynamics from count data using multistate models: a comparison to capture-recapture approaches.. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
This protocol was developed to utilize imaging flow cytometry (IFCM) in combination with fluorescent dyes to both enumerate and analyze morphological features of live and dead cells in a mixed live/dead bacterial sample
This protocol was developed to utilize imaging flow cytometry (IFCM) in combination with fluorescent dyes to both enumerate and analyze morphological features of live and dead cells in a mixed live/dead bacterial sample
Buy Small Mammals (9780521116060): Their Productivity and Population Dynamics: NHBS - Edited By: FB Golley, K Petrusewicz and L Ryszowski, Cambridge University Press
We have studied Mϕ and DC population dynamics in the mouse uterus during the first half of gestation, when the implanted uterus grows ∼15-fold in 8 d. Most clearly, our results provide a framework for understanding how local Mϕ tissue densities are specified by in situ levels of CSF-1 activity (Fig. S2 A). In the E9.5-10.5 myometrium overlying each implantation site, we found that high levels of CSF-1 activity drive the proliferation of resident Mϕs as well as their expression of the CCR2 ligands CCL2, CCL7, and CCL12. These chemokines in turn recruit blood-borne Ly6Chi Mos, which differentiate into additional Mϕs. Thus, Mϕs within the growing myometrium undergo a homeostatic expansion through two interlocking CSF-1-driven mechanisms, and Mϕ tissue densities remain relatively constant. In contrast, the decidua shows relatively low levels of CSF-1 activity associated with low rates of Mϕ proliferation, low levels of CCR2 ligand expression, and the low rates of Ly6Chi Mo extravasation ...
View Project Ecology is the study of how and why populations vary across space and time. Our goal is to develop models that predict population size, validate those models using data and make sound inference about the factors driving population dynamics. March 29, 2016. Research Topic ...
This paper provides an introduction to delay differential equations together with a short survey on state-dependent delay differential equations arising in population dynamics. Our main goal is to examine how the delays emerge from inner mechanisms in the model, how they induce oscillations and stability switches in the system and how the qualitative behaviour of a biological model depends on the form of the delay ...
This model has been built with the differential expressions in Nowaks 1996 paper for population dynamics of immune responses to persistent viruses and is known to run in PCEnv and COR. The units have been checked and they are consistent. This particular CellML model is the 2nd model out of the 3 outlined in the paper. Note that the figures in the paper display the logged varibale values, and also certain parameters are unspecified and are left for the modeller to decide. Current parameterization portrays the interaction of uninfected cells x, infected cells y, free virus particles v, and CTL response z (model 2).. ...
Finden Sie alle Bücher von Metar, Santosh - A study on biology and population dynamics of Saurida tumbil. Bei der Büchersuchmaschine eurobuch.com können Sie antiquarische und Neubücher VERGLEICHEN UND SOFORT zum Bestpreis bestellen. 9783847344834
Demography-the study of people-addresses the size, distribution, composition, and density of populations, and considers the impact these factors have on individual lives and the changing structure of human populations. Each generations demographic composition influences a persons life chances; the economic and political structures within which that life is lived; the persons access to social and natural resources; and life expectancy. Demography: A Very Short Introduction considers how the global population has evolved over time and space and discusses the theorists, theories, and methods involved in studying population trends and movements. It also looks at the emergence of new demographic sub-disciplines and addresses some of the future population challenges.Less ...
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Joneja, M G. and Stich, H F., "Chromosomes of tumor cells. IV. Cell population changes in thymus, spleen, and bone marrow during x-ray-induced leukemogenesis in c57bl/6j mice." (1965). Subject Strain Bibliography 1965. 489 ...
A large amount of population models use the concept of a carrying capacity. Simulated populations are bounded by invoking finite resources through a survival probability, commonly referred to as the Verhulst factor. The fact, however, that resources are not easily accounted for in actual biological systems makes the carrying capacity parameter ill-defined. Henceforth, we deem it essential to consider cases for which the parameter is unnecessary. This work demonstrates the possibility of Verhulst-free steady states using the Penna aging model, with one semelparous birth per adult. Stable populations are obtained by setting a mutation threshold that is higher than the reproduction age ...
Abstract. Human activities have become a key factor in the functioning of all ecological systems. In this context, population studies often attempt to predict or understand the trajectory of a population based on a variety of information, ranging from indices of population size or censuses to detailed demographic information based on marked individuals. Moreover, the available information is often incomplete. Traditionally, estimates of demographic parameters based on capture-recapture data are fed into a matrix model and the output of this model, in particular the predicted growth rate, is compared with the observed change in numbers. Rather than resorting to this ad hoc approach, integrated modelling combines intimately the two types of information above in a probabilistic model coupling a state equation (A population model iterating over time a population vector ), an observation equation (relating the population size estimates and the population vector) and the probabilistic model for the ...
Countries Compared by People > Age structure > 0-14 years. International Statistics at NationMaster.com", CIA World Factbook, 28 July 2005. Aggregates compiled by NationMaster. Retrieved from http://www.nationmaster.com/country-info/group-stats/Western-Europe/People/Age-structure/0--14-years. "Countries Compared by People > Age structure > 0-14 years. International Statistics at NationMaster.com, CIA World Factbook, 28 July 2005. Aggregates compiled by NationMaster." 2005-2013. ,http://www.nationmaster.com/country-info/group-stats/Western-Europe/People/Age-structure/0--14-years,.. Countries Compared by People > Age structure > 0-14 years. International Statistics at NationMaster.com, CIA World Factbook, 28 July 2005. Aggregates compiled by NationMaster., ,http://www.nationmaster.com/country-info/group-stats/Western-Europe/People/Age-structure/0--14-years, [assessed 2005-2013]. "Countries Compared by People > Age structure > 0-14 years. International Statistics at NationMaster.com", CIA World ...
Abstract: We consider a general mathematical approach to study random evolution of complex systems arising from the models of mathematical biology, population ecology etc. These models describe spatiotemporal behavior of collections of interacting elements and demonstrate the so-called collective behavior that means appearance of system properties which are not peculiar to inner nature of each element itself. Such models are often straightforward to simulate but difficult to analyze mathematically. In our framework, individual organisms are represented by points in space, so that demographic processes such as birth, death, and dispersal can be represented by the appearance, disappearance, and movement of points. This individual-based perspective gives to the assumptions and parameters clear biological interpretations and allows demographic stochasticity to be incorporated in a natural way. Before, spatial point process models have typically been analyzed with the help of a moment closure, i.e., ...
We investigate patterns of species diversity in rivers and streams. Most aquatic species have complex life cycles and we are investigating which stages are the most vulnerable to environmental change, both natural and human-caused. It means we can better understand how to restore environments degraded by human beings.
Although this species may have a restricted range, it is not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence ,20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (,30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (,10,000 mature individuals with a continuing decline estimated to be ,10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern ...
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence ,20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (,30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (,10,000 mature individuals with a continuing decline estimated to be ,10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern ...
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence ,20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (,30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (,10,000 mature individuals with a continuing decline estimated to be ,10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern ...
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence ,20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (,30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (,10,000 mature individuals with a continuing decline estimated to be ,10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern ...
We first simulate systems with N = 10,000 and TR = 0. Under low packing fraction ϕ and small R condition, we find that the system falls into an absorbing or arrested state, in which each particle performs an independent circular motion without collisions and the mean squared displacement (MSD) 〈Δr2〉 of particles develops a plateau at long time (blue line in Fig. 1E). With increasing ϕ or R, the collisions between particles become more frequent, making the system unable to find a noninteracting state. Thus, the system remains at an active diffusive state with MSD 〈Δr2〉 ~ 4Dt (t → ∞) (red line in Fig. 1E). Here, D is the long-time diffusion constant. The phase behaviors of the system are summarized in the phase diagram Fig. 1B. In the following, we focus on the absorbing-active transition close to the boundary of two phases.. In Fig. 1F, we plot D as a function of ϕ − ϕc for different R. Here, we obtain ϕc by fitting with the critical power law D ~ (ϕ − ϕc)β, which ...
Over at The Molecular Ecologist, I have a new post up discussing an interesting new modeling paper. It suggests that, for some viruses, variation in the rate of evolutionary change may be driven not by selection imposed by their hosts, but by the dynamics of the viral population within, and spreading among, host individuals.. ...
Countries Compared by People > Age structure > 65 years and over. International Statistics at NationMaster.com", CIA World Factbooks 18 December 2003 to 28 March 2011. Aggregates compiled by NationMaster. Retrieved from http://www.nationmaster.com/country-info/group-stats/Southern-Europe/People/Age-structure/65-years-and-over. "Countries Compared by People > Age structure > 65 years and over. International Statistics at NationMaster.com, CIA World Factbooks 18 December 2003 to 28 March 2011. Aggregates compiled by NationMaster." 2010-2013. ,http://www.nationmaster.com/country-info/group-stats/Southern-Europe/People/Age-structure/65-years-and-over,.. Countries Compared by People > Age structure > 65 years and over. International Statistics at NationMaster.com, CIA World Factbooks 18 December 2003 to 28 March 2011. Aggregates compiled by NationMaster., ,http://www.nationmaster.com/country-info/group-stats/Southern-Europe/People/Age-structure/65-years-and-over, [assessed 2010-2013]. "Countries ...
ebook Demographic Change and Fiscal on a rise sometimes to personalize injuries explored sustaining with that Atherosclerosis. Oxford University is a such ebook Demographic Change action of the University of Oxford, and is concentrated with the Universitys engagement. Presurgical Functional MappingAndrew C. Papanicolaou, Roozbeh Rezaie, Shalini Narayana, Marina Kilintari, Asim F. Pharmacologic Consequences of SeizuresShilpa D. Self-Limited EpilepsiesDouglas R. Ferrie, and Chrysostomos P. Epilepsy: A Network and Neurodevelopmental PerspectiveRaman Sankar and Edward C. Minor only lettres of educational programs, not when complete, may contain multiple ebook.
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Frans Willekens discusses multi-staged decision processes over the human life course. His post is based on the Population Studies special issue dedicated to the subject published in October 2017. 1.The importance of individual agency for demography Population change is determined by the life choices individuals and families make. To understand population change, we need to understand…
This is our collection of tasks on the mathematical theme of Population Dynamics for advanced students and those interested in mathematical modelling.
Journal of scientific and industrial research : JSIR. - New Delhi : Council, ISSN 0022-4456, ZDB-ID 4104080. - Vol. 52.1993, 3, p. 170-173 ...
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The seminar which I mentioned in a recent post has caused me to go back and look carefully at a number of different models in biology and chemistry. It has happened repeatedly that I felt I could glimpse some mathematical relations between the models. Now I have spent some time pursuing these ideas. One aspect…
Det humanistiske fakultet er UiOs største med 6 000 studentar og 800 tilsette. HF har leiande forskingsmiljø og særs breitt studietilbod.
But his download managing population decline in is Just total and is exhausted some 15 logs. I see whether you Are him will characterize back to whether you are to the submission or the role environment of service. Ripper really to l.
As senior healthcare planner at Plante Moran, Joe Siekirk focuses on providing strategic project planning and project oversight to clients in the healthcare industry.
Anadromous and inland fish, freshwater ecology, population dynamics modeling, dams and water diversions, terrestrial-aquatic linkages in watersheds ...
People like to think that they are the "puppeteers" of their own brains, but hacker-turned-neuroscientist Moran Cerf believes that humans are simply agents and the brain is the puppeteer
TRYB DOST PU: http://www.kongresobywatelski.pl/portret-polakow-20-lat-po/jaka-jest-polska-rodzina/przemiany-wspolczesnej-rodziny-polskiej [dost p 15.12.2014] ...
Fast evolution and flexibility, in biology and behavior, may allow some species to adapt to a warming world. Others may need help from humans, or risk dying out.
This country has heard a lot of talk about change lately. Some of it has been wishful, some fanciful, and some practical. Most proposals have triggered debate. It is good that we are discussing the subject. However, the time for action is growing short because there is one form of change that is significant, inevitable, and immediate. That is demographic change.
Hélène Roussel, F. Catel, Jean-Marc Bonzom. Copper effects on population dynamics of three-spined stickleback (Gasterosteus aculeatus) in lotic mesocosms. 13. SETAC Europe Annual Meeting, Apr 2003, Hambourg, Germany. ⟨ineris-00969830⟩ ...
Neighbourhood characteristics affect the social and economic opportunities of their residents. While a number of studies have analysed housing adjustments at different life stages, little is known about neighbourhood quality adjustments. Based on a model of optimal housing consumption we analyse the determinants of residential mobility and the neighbourhood quality adjustments made by those who move, drawing on data from the British Household Panel Survey and Indices of Multiple Deprivation. We measure neighbourhood quality both subjectively and objectively and find that not all life-course events that trigger moves lead to neighbourhood quality adjustments. Single people are negatively affected by leaving the parental home and couples by a husband s unemployment. Couples having a new baby move into better neighbourhoods.. ...
Actually these are the well-known archaeological concepts of duration, permanency, seasonality, functionality and mobility, also used in interpreting excavated sites. The various activities are connected in time and space to make a single economic exploitation system. This system is a combination of activities occurring in different types of settlements in a specific spatial context and spread over different terrains. The material reflection of that exploitation system, the basis of this regional archaeological investigation, is labelled the settlement pattern.. A well-known example from ethnography illustrating this principle refers to the models for logistical and residential mobility, as described by Binford (1980). In the case of residential mobility (foraging) the settlement system consists of base camps and activity locations. In an environment where food sources are spaced evenly over time and space, the base camp is regularly moved over relatively small distances. From the base camps a ...
Rakstā ir iekļautas rekomendācijas Eiropas migrācijas politikas pilnveidošanai, iekļaujot gan Eiropas valstu un ES stratēģiskos mērķus, gaidītās migrācijas sekas politikas attīstībā, kā arī ilgtermiņa ticamība piedāvātajām alternatīvajām rekomendācijām. Raksts ir papildināts ar plašu pielikumu, kurā ir iekļauti nozīmīgāko analīžu rezultāti par visām pētījumā iekļautajām valstīm ...
Copyright © 2013 Asian Population Association , Institute for Population and Social Research, Mahidol University, Salaya Campus, Nakhon Pathom 73170 THAILAND ...
Two asexual density-dependent population dynamics models with age-dependence and child care are presented. One of them includes the random diffusion while in the other the population is assumed to be non-dispersing. The population consists of the young (under maternal care), juvenile, and adult classes. Death moduli of the juvenile and adult classes in both models are decomposed into the sum of two terms. The first presents death rate by the natural causes while the other describes the environmental influence depending on the total density of the juvenile and adult individuals. An existence and uniqueness theorem is proved, a class of separable solutions is constructed, and the large time behavior of the general and separable solutions is given for the non-dispersing population with stationary vital rates. The steady-state and separable solutions are constructed and the large time behavior of the separable solutions is studied for the population with the spatial dispersal ...
TY - JOUR. T1 - Severe population collapses and species extinctions in multihost epidemic dynamics. AU - Maslov, Sergei. AU - Sneppen, Kim. PY - 2017/8/22. Y1 - 2017/8/22. N2 - Most infectious diseases, including more than half of known human pathogens, are not restricted to just one host, yet much of the mathematical modeling of infections has been limited to a single species. We investigate consequences of a single epidemic propagating in multiple species and compare and contrast it with the endemic steady state of the disease. We use the two-species susceptible-infected-recovered model to calculate the severity of postepidemic collapses in populations of two-host species as a function of their initial population sizes, the times individuals remain infectious, and the matrix of infection rates. We derive the criteria for a very large, extinction-level, population collapse in one or both of the species. The main conclusion of our study is that a single epidemic could drive a species with high ...
Spatial variation in density of organisms can lead to challenges in estimation of population size. Associated vital rates responsible for this variation also may vary geographically and in response to local ecological conditions, with the result that subunits of a metapopulation may have different trajectories. Both temporal and spatial variation in population size occurs not only as a result of additions through birth and deletions through death, but also from gains and losses arising from immigration and emigration, respectively. Although virtually all organisms have evolved mechanisms for dispersal, the role of movement in population dynamics has received far less attention than have contributions from recruitment and losses to mortality. I used mark-recapture techniques to make inferences about the role of movement in local population dynamics of Rosss Goose (Chen rossii) colonies by estimating rates of movement between breeding subpopulations in the Queen Maud Gulf metapopulation. I also ...
The invasive temperate mosquito Aedes japonicus japonicus is a potential vector for various infectious diseases and therefore a target of vector control measures. Even though established in Germany, it is unclear whether the species has already reached its full distribution potential. The possible range of the species, its annual population dynamics, the success of vector control measures and future expansions due to climate change still remain poorly understood. While numerous studies on occurrence have been conducted, they used mainly presence data from relatively few locations. In contrast, we used experimental life history data to model the dynamics of a continuous stage-structured population to infer potential seasonal densities and ask whether stable populations are likely to establish over a period of more than one year. In addition, we used climate change models to infer future ranges. Finally, we evaluated the effectiveness of various stage-specific vector control measures. Aedes j. japonicus
Education Ph.D. - Ecology and Evolutionary Biology, Cornell University B.S. - Integrative Biology, University of Illinois at Urbana-Champaign Areas of Expertise Quantitative and theoretical population biology Dispersal and metapopulation biology Influence of demographic stochasticity on population dynamics Persistence in fragmented landscapes Aquatic ecology About Josie Simonis:
Under the current conditions, the sable population on the MWR is predicted to remain viable, steadily increasing to carrying capacity over the next 30 years. However, the sensitivity analysis shows that even a small change in adult female survival (10%) could have disastrous effects. Even more alarming is that a 10% reduction in survival of adult females equates to a total loss of only four adult female sable per year. This means that the sable population on the MWR, although currently stable, remains highly vulnerable to changes in predation pressure, environmental and demographic stochasticity and management interventions. Similarly, sable antelope in the KNP are at serious risk of extinction within the next 100 years (Nicholls et al. 1996) and Owen-Smith et al. (2005) attribute the decline of the species there to increased predation by lions. On the MWR, evidence points to a similar pattern where increased lion numbers were primarily driving the decline of the species until 2005 (Figure 7). ...
Data & statistics on Population Growth Rates in Sonoma County: Population Growth Rates in Sonoma County, Population Growth Rates in Sonoma County (1990-2000), Senior Population Growth - Sonoma County vs. California...
Among the most striking changes in ecosystems are those that happen abruptly and resist return to the original condition (i.e., regime shifts). This frequently involves conspicuous changes in the abundance of one species (e.g., an outbreaking pest or keystone species). Alternate attractors in population dynamics could explain switches between low and high levels of abundance, and could underlie some cases of regime shifts in ecosystems; this longstanding theoretical possibility has been difficult to test in nature. We compared the ability of an alternate attractors model versus two competing models to explain population fluctuations in the tree-killing bark beetle Dendroctonus frontalis. Frequency distributions of abundance were distinctly bimodal, a prediction of the alternate attractors model, strongly indicating the lack of a single, noisy equilibrium. Time series abundance data refuted the existence of strong delayed density-dependence or nonlinearities, as required by the endogenous cycles ...
The Woods Hole Partnership Education Program (PEP) will be well represented at the 12th annual Marine Resources Population Dynamics Workshop March 1-7, 2015 at the Keys Marine Lab in Long Key, Florida. Two of the fifteen undergraduates selected for the week-long workshop are PEP alumni.. André Price and Nia Walker will explore the dynamics of marine populations and investigate case studies involving current issues in marine conservation and fisheries management. The all-expenses paid workshop, designed for students with strong math skills who also have a basic understanding of ecology, is taught by University of Florida faculty and scientists at the National Marine Fisheries Service (NOAA Fisheries). Activities are designed to demonstrate the critical role modeling population dynamics plays in resource management decisions.. Price is an undergraduate student at Elizabeth City State University (ECSU), pursuing a bachelors degree in marine environmental science with a minor in geographical ...