scholarly journals Phylogeography of Ustilago maydis virus H1 in the USA and Mexico

2006 ◽  
Vol 87 (11) ◽  
pp. 3433-3441 ◽  
Author(s):  
Peter D. Voth ◽  
Linah Mairura ◽  
Ben E. Lockhart ◽  
Georgiana May
Keyword(s):  
Population Dynamics ◽  
Genetic Structure ◽  
Evolutionary History ◽  
Evolutionary Dynamics ◽  
Ustilago Maydis ◽  
Neutral Evolution ◽  
Ancestral Population ◽  
Nucleotide Sequence Variation ◽  
The Usa ◽  
The Impact

Ustilago maydis virus H1 (Umv-H1) is a mycovirus that infects Ustilago maydis, a fungal pathogen of maize. As Zea mays was domesticated, it carried with it many associated symbionts, such that the subsequent range expansion and cultivation of maize should have affected maize symbionts' evolutionary history dramatically. Because transmission of Umv-H1 takes place only through cytoplasmic fusion during mating of U. maydis individuals, the population dynamics of U. maydis and maize are expected to affect the population structure of the viral symbiont strongly. Here, the impact of changes in the evolutionary history of U. maydis on that of Umv-H1 was investigated. The high mutation rate of this virus allows inferences to be made about the evolution and divergence of Umv-H1 lineages as a result of the recent changes in U. maydis geographical and genetic structure. The phylogeographical history and genetic structure of Umv-H1 populations in the USA and Mexico were determined by using analyses of viral nucleotide sequence variation. Infection and recombination frequencies, genetic diversity and rates of neutral evolution were also assessed, to make inferences regarding evolutionary processes underlying the population genetic structure of ancestral and descendent populations. The results suggest that Mexico represents the ancestral population of Umv-H1, from which the virus has been carried with U. maydis populations into the USA. Thus, the population dynamics of one symbiont represent a major evolutionary force on the co-evolutionary dynamics of symbiotic partners.

scholarly journals The impact of COVID-19 non-pharmaceutical interventions on the future dynamics of endemic infections

2020 ◽  
Author(s):  
Rachel E. Baker ◽  
Sang Woo Park ◽  
Wenchang Yang ◽  
Gabriel A. Vecchi ◽  
C. Jessica E. Metcalf ◽  
...  
Keyword(s):  
Evolutionary Dynamics ◽  
The United States ◽  
Endemic Diseases ◽  
Laboratory Surveillance ◽  
The Usa ◽  
Syncytial Virus ◽  
Uncertain Future ◽  
The Impact ◽  
Pharmaceutical Interventions ◽  
Endemic Infections

AbstractNon-pharmaceutical interventions (NPIs) have been employed to reduce the transmission of SARS-CoV-2, yet these measures are already having similar effects on other directly-transmitted, endemic diseases. Disruptions to the seasonal transmission patterns of these diseases may have consequences for the timing and severity of future outbreaks. Here we consider the implications of SARS-CoV-2 NPIs for two endemic infections circulating in the United States of America (USA): respiratory syncytial virus (RSV) and seasonal influenza. Using laboratory surveillance data from 2020, we estimate that RSV transmission declined by at least 20% in the USA at the start of the NPI period. We simulate future trajectories of both RSV and influenza, using an epidemic model. As susceptibility increases over the NPI period, we find that substantial outbreaks of RSV may occur in future years, with peak outbreaks likely occurring in the winter of 2021-2022. Results for influenza broadly echo this picture, but are more uncertain; future outbreaks are likely dependent on the transmissibility and evolutionary dynamics of circulating strains.

scholarly journals Inconsistent genetic structure among members of a multitrophic system: did bruchid parasitoids (Horismenusspp.) escape the effects of bean domestication?

2012 ◽  
Vol 103 (2) ◽  
pp. 182-192 ◽  
Author(s):  
S. Laurin-Lemay ◽  
B. Angers ◽  
B. Benrey ◽  
J. Brodeur
Keyword(s):  
Genetic Structure ◽  
Host Plant ◽  
Evolutionary History ◽  
Evolutionary Dynamics ◽  
Trophic Levels ◽  
Plant Domestication ◽  
Parasitoid Species ◽  
Genetic Structuring ◽  
Ancestral Gene ◽  
History Of

AbstractAnthropogenic range expansion and cultural practices have modified the distribution, abundance and genetic diversity of domesticated organisms, thereby altering multitrophic assemblages through space and time. The putative Mesoamerican domestication centre of the common bean,Phaseolus vulgarisL., in Mexico allows investigating the effects of plant domestication on the genetic structure of members of a multitrophic system. The aim of this study was to compare the evolutionary history ofHorismenusparasitoids (Hymenoptera: Eulophidae) to those of their bruchid beetle hosts (Coleoptera: Bruchidae) and their domesticated host plant (P. vulgaris), in the context of traditional agriculture in Mexico. We analyzed the population genetic structure of fourHorismenusspecies in Mexico using mitochondrialCOIhaplotype data. The two most abundant parasitoid species wereHorismenus depressusandHorismenus missouriensis. Horismenus missouriensiswere infected byWolbachiaendosymbionts and had little to no population differentiation (FST = 0.06). We suspect the mitochondrial history ofH. missouriensisto be blurred byWolbachia, because differentiation among infected vs. non-infected individuals exists (FST = 0.11). Populations ofH. depressuswere found to be highly differentiated (FST = 0.34), but the genetic structuring could not be explained by tested spatial components. We then compared the genetic structure observed in this parasitoid species to previously published studies on bruchid beetles and their host plants. Despite extensive human-mediated migration and likely population homogenization of its twoAcanthoscelidesbruchid beetle hosts,H. depressuspopulations are structured like its host plant, by a recent dispersal from a diverse ancestral gene pool. Distinct evolutionary dynamics may explain inconsistent patterns among trophic levels. Parasitoids likely migrate from wild bean populations and are poorly adapted to bean storage conditions similar to their bruchid beetle hosts. Integrating several trophic levels to the study of evolutionary history has proven to be fruitful in detecting different ecological responses to human-mediated disturbances and host parasite interactions.

scholarly journals Genetic Structure and Evolutionary History of Rhinopithecus roxellana in Qinling Mountains, Central China

2021 ◽  
Vol 11 ◽  
Author(s):  
Yuli Li ◽  
Kang Huang ◽  
Shiyi Tang ◽  
Li Feng ◽  
Jia Yang ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Evolutionary History ◽  
Evolutionary Dynamics ◽  
Central China ◽  
Rhinopithecus Roxellana ◽  
Qinling Mountains ◽  
Ecological Niche Models ◽  
Effective Population ◽  
Intraspecific Divergence ◽  
Contemporary Gene Flow

The Qinling mountainous region is one of the world's biodiversity hotspots and provides refuges for many endangered endemic animals. The golden snub-nosed monkeys (Rhinopithecus roxellana) are considered as a flagship species in this area. Here, we depicted the genetic structure and evolutionary history via microsatellite markers and combination with the ecological niche models (ENMs) to elucidate the intraspecific divergent and the impacts of the population demography on our focal species. Our results revealed three distinct subpopulations of R. roxellana and also uncovered asymmetric historical and symmetric contemporary gene flow that existed. Our evolutionary dynamics analyses based on diyabc suggested that the intraspecific divergence accompanied with effective population sizes changes. The ENM result implied that the distribution range of this species experienced expansion during the last glacial maximum (LGM). Our results highlighted that geological factors could contribute to the high genetic differentiation within the R. roxellana in the Qinling Mountains. We also provided a new insight into conservation management plans with endangered species in this region.

Long-term population dynamics of the red deer and European roe deer at the protected and not-protected areas in Mountain Crimea

2017 ◽  
Vol 7 (4) ◽  
pp. 65-72
Author(s):  
V. N. Shmagol' ◽  
V. L. Yarysh ◽  
S. P. Ivanov ◽  
V. I. Maltsev
Keyword(s):  
Population Dynamics ◽  
Protected Areas ◽  
Red Deer ◽  
Nature Reserve ◽  
Roe Deer ◽  
Precipitation Amount ◽  
Annual Precipitation ◽  
Population Number ◽  
The Impact

<p>The long-term population dynamics of the red deer (<em>Cervus elaphus</em> L.) and European roe deer (<em>Capreolus</em> <em>capreolus</em> L.) at the mountain and forest zone of Crimea during 1980-2017 is presented. Fluctuations in numbers of both species are cyclical and partly synchronous. Period of oscillations in the population of red deer is about 25 years, the average duration of the oscillation period of number of roe deer is 12.3 years. During the fluctuations in the number the increasing and fall in population number of the red deer had been as 26-47 %, and roe deer – as 22-34 %. Basing on the dada obtained we have assumed that together with large-scale cycles of fluctuations in population number of both red deer and roe deer the short cycles of fluctuations in the number of these species with period from 3.5 to 7.5 years take place. Significant differences of the parameters of cyclical fluctuations in the number of roe deer at some sites of the Mountainous Crimea: breaches of synchronicity, as well as significant differences in the duration of cycles are revealed. The greatest deviations from the average values of parameters of long-term dynamics of the number of roe deer in Crimea are noted for groups of this species at two protected areas. At the Crimean Nature Reserve the cycle time of fluctuations of the numbers of roe deer was 18 years. At the Karadag Nature Reserve since 1976 we can see an exponential growth in number of roe deer that is continued up to the present time. By 2016 the number of roe deer reached 750 individuals at a density of 437 animals per 1 thousand ha. Peculiarity of dynamics of number of roe deer at some sites proves the existence in the mountain forest of Crimea several relatively isolated groups of deer. We assumed that "island" location of the Crimean populations of red deer and European roe deer, their relatively little number and influence of permanent extreme factors of both natural and anthropogenic origination have contributed to a mechanism of survival of these populations. The elements of such a mechanism include the following features of long-term dynamics of the population: the reduction in the period of cyclic population fluctuations, while maintaining their amplitude and the appearance of additional small cycles, providing more flexible response of the population to the impact of both negative and positive environmental factors. From the totality of the weather conditions for the Crimean population of roe deer the recurring periods of increases and downs in the annual precipitation amount may have relevance. There was a trend of increase in the roe deer population during periods of increasing annual precipitation.</p>

SCENARIOS FOR AN EXPANDING DEMAND OF TOURISM ON THE COASTS OF CUBA

2017 ◽  
Author(s):  
Oscar Gutiérrez-Bolívar ◽  
Oscar Gutiérrez-Bolívar ◽  
Pedro Fernández Carrasco ◽  
Pedro Fernández Carrasco
Keyword(s):  
United States ◽  
The Other ◽  
Sudden Increase ◽  
Tourist Destination ◽  
Other Hand ◽  
The Usa ◽  
The Impact

The opening of relationships between United States and Cuba could be a drive for a huge increase in the affluence of tourism to Cuba and especially to the coast areas. Cuba has been for many years an important tourist destination for people from many countries, but almost forbidden for US citizens. The proximity of the USA, its amount of population as well as their great acquisition power will increase in a very substantial way the demand for accommodation and other uses in the proximity of the coasts. There will be a need to implement a package of measures that reduce the impact of such sudden increase in the coastal line. On the other hand that augment in tourism could be an opportunity to improve the standard of life of Cubans. The consideration of different possibilities of such development, the analysis of the damages that each one could cause as well as the measures that could avoid, ameliorate or compensate such effects are the goals that are going to be presented in this paper.

Socio-Technological Aspects of Automation in Public Works Activities

1987 ◽  
Vol 19 (3-4) ◽  
pp. 633-643
Author(s):  
William F. Garber
Keyword(s):  
Industrial Revolution ◽  
Work Force ◽  
Public Works ◽  
Human Society ◽  
Training Problem ◽  
Total Employment ◽  
The Usa ◽  
History Of ◽  
Complete Automation ◽  
The Impact

The history of human society is replete with examples of advances in technology overrunning the ability of societal organizations to efficiently handle the resulting massive societal dislocations. The social impacts of the “Industrial Revolution of the 18th and 19th Centuries” illustrate how profound such effects can be. The automation-computer-robotics revolution now underway also has the potential for serious societal changes. In this regard public works activities are subject to increasing amounts of automation with impacts upon current and net total employment and training needs. To evaluate the present status of automation in the USA, questionnaires were sent to public works authorities in 110 cities or agencies. The current degree of automation, the impact upon employment and the skills now needed by public works employers were queried. It was found that in most cases automation was just starting; but that as complete automation as was possible was inevitable given the increasing complexity of the tasks, the demands of the public and the long term prospects for public works funding. In many cases the candidates now in the work force were not properly trained for automation needs. Retraining and changes in the educational system appeared necessary if the employees now needed were to be continuously available. Public works management as well as several labor organizations appeared to be aware of this need and were organizing to handle the training problem and the changes in employment qualifications now necessary. It appeared to be a consensus that the larger societal effects of automation should be handled by society as a whole.

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