scholarly journals Microparasite dispersal in metapopulations: a boon or bane to the host population?

2018 ◽  
Vol 285 (1885) ◽  
pp. 20181519 ◽  
Author(s):  
Christina P. Tadiri ◽  
Marilyn E. Scott ◽  
Gregor F. Fussmann
Keyword(s):  
Disease Transmission ◽  
Species Conservation ◽  
Host Population ◽  
Isolated Populations ◽  
Parasite Abundance ◽  
Low Level ◽  
Parasite Distribution ◽  
High Level ◽  
Host Parasite ◽  
The Impact

Although connectivity can promote host species persistence in a metapopulation, dispersal may also enable disease transmission, an effect further complicated by the impact that parasite distribution may have on host–parasite population dynamics. We investigated the effects of connectivity and initial parasite distribution (clustered or dispersed) on microparasite–host dynamics in experimental metapopulations, using guppies and Gyrodactylus turnbulli . We created metapopulations of guppies divided into four subpopulations and introduced either a low level of parasites to all subpopulations (dispersed) or a high level of parasites to one subpopulation (clustered). Controlled migration among subpopulations occurred every 10 days. In additional trials, we introduced low or high levels of parasites to isolated populations. Parasites persisted longer in metapopulations than in isolated populations. Mortality was lowest in isolated populations with low-level introductions. The interaction of connectivity and initial parasite distribution influenced parasite abundance. With low-level introductions, connectivity helped the parasite persist longer but had little effect on the hosts. With high levels, connectivity also benefited the hosts, lowering parasite burdens. These findings have implications for disease management and species conservation.

scholarly journals A CloudSat–CALIPSO View of Cloud and Precipitation Properties across Cold Fronts over the Global Oceans

2015 ◽  
Vol 28 (17) ◽  
pp. 6743-6762 ◽  
Author(s):  
Catherine M. Naud ◽  
Derek J. Posselt ◽  
Susan C. van den Heever
Keyword(s):  
Large Scale ◽  
Cold Front ◽  
Conveyor Belt ◽  
Low Level ◽  
Scale Parameters ◽  
Convective Clouds ◽  
Cold Fronts ◽  
Surface Front ◽  
High Level ◽  
The Impact

Abstract The distribution of cloud and precipitation properties across oceanic extratropical cyclone cold fronts is examined using four years of combined CloudSat radar and CALIPSO lidar retrievals. The global annual mean cloud and precipitation distributions show that low-level clouds are ubiquitous in the postfrontal zone while higher-level cloud frequency and precipitation peak in the warm sector along the surface front. Increases in temperature and moisture within the cold front region are associated with larger high-level but lower mid-/low-level cloud frequencies and precipitation decreases in the cold sector. This behavior seems to be related to a shift from stratiform to convective clouds and precipitation. Stronger ascent in the warm conveyor belt tends to enhance cloudiness and precipitation across the cold front. A strong temperature contrast between the warm and cold sectors also encourages greater post-cold-frontal cloud occurrence. While the seasonal contrasts in environmental temperature, moisture, and ascent strength are enough to explain most of the variations in cloud and precipitation across cold fronts in both hemispheres, they do not fully explain the differences between Northern and Southern Hemisphere cold fronts. These differences are better explained when the impact of the contrast in temperature across the cold front is also considered. In addition, these large-scale parameters do not explain the relatively large frequency in springtime postfrontal precipitation.

scholarly journals A Two-Level Sound Classification Platform for Environmental Monitoring

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Stelios A. Mitilineos ◽  
Stelios M. Potirakis ◽  
Nicolas-Alexander Tatlas ◽  
Maria Rangoussi
Keyword(s):  
Cultural Heritage ◽  
Organizational Innovation ◽  
Gaussian Mixture ◽  
Low Level ◽  
Heritage Sites ◽  
Acoustic Sensor Networks ◽  
Preventive Actions ◽  
Integrated Platform ◽  
High Level ◽  
The Impact

STORM is an ongoing European research project that aims at developing an integrated platform for monitoring, protecting, and managing cultural heritage sites through technical and organizational innovation. Part of the scheduled preventive actions for the protection of cultural heritage is the development of wireless acoustic sensor networks (WASNs) that will be used for assessing the impact of human-generated activities as well as for monitoring potentially hazardous environmental phenomena. Collected sound samples will be forwarded to a central server where they will be automatically classified in a hierarchical manner; anthropogenic and environmental activity will be monitored, and stakeholders will be alarmed in the case of potential malevolent behavior or natural phenomena like excess rainfall, fire, gale, high tides, and waves. Herein, we present an integrated platform that includes sound sample denoising using wavelets, feature extraction from sound samples, Gaussian mixture modeling of these features, and a powerful two-layer neural network for automatic classification. We contribute to previous work by extending the proposed classification platform to perform low-level classification too, i.e., classify sounds to further subclasses that include airplane, car, and pistol sounds for the anthropogenic sound class; bird, dog, and snake sounds for the biophysical sound class; and fire, waterfall, and gale for the geophysical sound class. Classification results exhibit outstanding classification accuracy in both high-level and low-level classification thus demonstrating the feasibility of the proposed approach.

scholarly journals The effects of grouping types on promoting critical thinking in EFL collaborative writing

2020 ◽  
Vol 9 (2) ◽  
pp. 108-120
Author(s):  
Nguyen Thi Minh Tram ◽  
Bui Thi Thuc Quyen
Keyword(s):  
Critical Thinking ◽  
Collaborative Learning ◽  
Tertiary Education ◽  
Collaborative Writing ◽  
Homogeneous Groups ◽  
Learning And Teaching ◽  
Low Level ◽  
Heterogeneous Groups ◽  
High Level ◽  
The Impact

Nurturing critical thinking (CT) has been acknowledged as a core objective of tertiary education, and drawn attention from academia of teaching English as a Foreign Language (EFL), particularly in EFL argumentative writing. It has been claimed that collaborative learning which stimulates the active exchange of ideas within small groups not only increases interest among the participants but also promotes critical thinking. One of the important aspects of learning and teaching through collaboration is the group composition or grouping “who with whom”. The present study was an attempt to investigate the impact of homogeneous and heterogeneous groupings on critical thinking in collaborative writing. Having been required to write an argumentative essay as a pre-test, 75 participants, who were categorized by their prior critical thinking levels, were assigned into three group types: heterogeneous, homogeneous high and homogeneous low groups. As a consequence, four types of students were considered their improvement before and after the experiment: high-level students in heterogeneous groups, lowlevel students in heterogeneous groups, high-level students in homogeneous groups, low-level students in homogeneous groups. The results demonstrated that learners improved their critical thinking level through collaborative writing, whether working with stronger or weaker peers. However, heterogeneous grouping showed superiority over homogeneous grouping at the low level. The results revealed that cooperative learning could be especially beneficial for low students. It is hoped that the findings of the present study will give teachers deep insights into group compositions in collaborative learning courses, and will help them make better group experiences for students.

scholarly journals Antibiotic-driven Escape of Host in a Parasite-induced Red Queen Dynamics

2018 ◽  
Author(s):  
Elizabeth L. Anzia ◽  
Jomar F. Rabajante
Keyword(s):  
Mathematical Model ◽  
Stable Equilibrium ◽  
Parasitic Infections ◽  
Red Queen ◽  
Good Practices ◽  
Low Level ◽  
High Level ◽  
Host Parasite ◽  
The Red Queen

AbstractWinnerless coevolution of hosts and parasites could exhibit Red Queen dynamics, which is characterized by parasite-driven cyclic switching of expressed host phenotypes. We hypothesize that the application of antibiotics to suppress the reproduction of parasites can provide opportunity for the hosts to escape such winnerless coevolution. Here, we formulate a minimal mathematical model of host-parasite interaction involving multiple host phenotypes that are targeted by adapting parasites. Our model predicts the levels of antibiotic effectiveness that can steer the parasite-driven cyclic switching of host phenotypes (heteroclinic oscillations) to a stable equilibrium of host survival. Our simulations show that uninterrupted application of antibiotic with high-level effectiveness (> 85%) is needed to escape the Red Queen dynamics. Intermittent and low level of antibiotic effectiveness are indeed useless to stop host-parasite coevolution. This study can be a guide in designing good practices and protocols to minimize risk of further progression of parasitic infections.

scholarly journals Effect of Interventional Programme on Enhancing Empowerment Status through Decision Making Skills of Tribal Working Women in Utnoor Mandal Adilabad District, India

2021 ◽  
pp. 41-45
Author(s):  
N. Sandhya Rani ◽  
M. Sarada Devi
Keyword(s):  
Decision Making ◽  
Working Women ◽  
Total Sample ◽  
Average Level ◽  
Sample Population ◽  
Test Results ◽  
Low Level ◽  
Tribal Women ◽  
High Level ◽  
The Impact

Empowerment of tribal women is one of the central issues in the process of development all over the world. Empowerment is the process that allows one to gain the knowledge and attitude needed to cope with the changing world and the circumstances in which one lives [1]. Women empowerment is a process in which women gain greater share of control over material, human and intellectual resources as well as control over decision-making in their home, community, society and nation. Given the need to analyze the empowerment status of tribal women, the present study aimed to enhance the empowerment status through enhancing decision-making skills of tribal working women in India. The specific objective is to study the impact of intervention on enhancing status of empowerment through decision-making skills of tribal working women in Utnoor Mandal Adilabad district. The total sample population for the study was 50 tribal working women, and data was analyzed using a paired t test. Results revealed that at pretest, majority of the women were at average level of decision-making skills (78%), 12% were at low level and only 10% were at high level. After the intervention, post test results revealed that 74% of the women were high in decision making skills and remaining 26% were at average level. Interestingly, none of the respondents had low level of life skills. Thus, intervention found to be effective among women respondents to develop and enhance their empowerment status through decision-making skills.

scholarly journals The mode of host–parasite interaction shapes coevolutionary dynamics and the fate of host cooperation

2012 ◽  
Vol 279 (1743) ◽  
pp. 3742-3748 ◽  
Author(s):  
Benjamin J. Z. Quigley ◽  
Diana García López ◽  
Angus Buckling ◽  
Alan J. McKane ◽  
Sam P. Brown
Keyword(s):  
Stochastic Modelling ◽  
Host Population ◽  
Social Traits ◽  
The Social ◽  
Population Structures ◽  
Modelling Techniques ◽  
Virus Interactions ◽  
Host Parasite ◽  
The Impact ◽  
Genetic Specificity

Antagonistic coevolution between hosts and parasites can have a major impact on host population structures, and hence on the evolution of social traits. Using stochastic modelling techniques in the context of bacteria–virus interactions, we investigate the impact of coevolution across a continuum of host–parasite genetic specificity (specifically, where genotypes have the same infectivity/resistance ranges (matching alleles, MA) to highly variable ranges (gene-for-gene, GFG)) on population genetic structure, and on the social behaviour of the host. We find that host cooperation is more likely to be maintained towards the MA end of the continuum, as the more frequent bottlenecks associated with an MA-like interaction can prevent defector invasion, and can even allow migrant cooperators to invade populations of defectors.

scholarly journals Continuous Flash Suppression Known and Unknowns

2019 ◽  
Author(s):  
Ali Pournaghdali ◽  
Bennett L Schwartz
Keyword(s):  
Visual Processing ◽  
Visual Information ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Experimental Configuration ◽  
High Level ◽  
The Impact ◽  
Nonconscious Perception

Studies utilizing continuous flash suppression (CFS) provide valuable information regarding conscious and nonconscious perception. There are, however, crucial unanswered questions regarding the mechanisms of suppression and the level of visual processing in the absence of consciousness with CFS. Research suggests that the answers to these questions depend on the experimental configuration and how we assess consciousness in these studies. The aim of this review is to evaluate the impact of different experimental configurations and the assessment of consciousness on the results of the previous CFS studies. We review studies that evaluated the influence of different experimental configuration on the depth of suppression with CFS and discuss how different assessments of consciousness may impact the results of CFS studies. Finally, we review behavioral and brain recording studies of CFS. In conclusion, previous studies provide evidence for survival of low-level visual information and complete impairment of high-level visual information under the influence of CFS. That is, studies suggest that nonconscious perception of lower-level visual information happens with CFS but there is no evidence for nonconscious highlevel recognition with CFS.

scholarly journals The Impact of Patents and R&D Cooperation on R&D Investments in a Differentiated Goods Industry

2020 ◽  
Vol 15 (1) ◽  
pp. 122-133
Author(s):  
Adam Karbowski ◽  
Jacek Prokop
Keyword(s):  
Patent Protection ◽  
Differentiated Products ◽  
Policy Makers ◽  
Low Level ◽  
Differentiated Goods ◽  
High Level ◽  
The Impact

AbstractIn this paper, we consider the impact of patents and R&D cooperation on R&D investments in the oligopolistic industry with differentiated products. Four types of firms’ conduct are investigated: R&D competition without patents, R&D competition with patent protection, R&D cooperation, and the full industry cooperation. The obtained results suggest that patents do not necessarily promote R&D investments due to the existence of so called tournament effects. R&D cooperation stimulates R&D investments, but R&D cooperation provides sufficient incentives to create a full industry cartel. Such a cartel works to the detriment of consumers. Our analysis led us to the conclusion that for a relatively low level of R&D spillovers, the policy-makers should promote R&D competition without patent protection among oligopolistic firms. For a relatively high level of R&D spillovers, R&D cooperation enhances innovation, but the regulator should monitor the market for probable collusion.

scholarly journals Stress level and health locus of control in parents of hospitalized newborns – preliminary report

2018 ◽  
Vol 17 (4) ◽  
pp. 26-32
Author(s):  
Anna B. Pilewska-Kozak ◽  
Beata B. Dobrowolska ◽  
Anna Majewska ◽  
Grażyna Stadnicka ◽  
Agnieszka K. Pawłowska-Muc ◽  
...  
Keyword(s):  
Locus Of Control ◽  
Health Locus Of Control ◽  
Survey Method ◽  
Dominant Type ◽  
Low Level ◽  
Health Control ◽  
Undifferentiated Type ◽  
Control Locus ◽  
High Level ◽  
The Impact

AbstractAim. The study was to assess the level of stress and the health locus of control in parents of hospitalized newborns.Material and methods. The study covered a group of 150 parents of 126 newborns who were hospitalized in the Neonatal Pathology Ward at the University Children’s Hospital in Lublin. The diagnostic survey method was applied with the use of an original questionnaire as well as some standardized tools: Perceived Stress Scale (PSS-10) and Multidimensional Health Locus of Control Scale (MHLC – version B).Results. In more than a half of the subjects (54.0%), a high level of stress was observed. Every fourth (26.1%) parent was characterized by an average level of stress and nearly every fifth (19.3%) by a low level of stress. The highest indicator was characterized by the domain of the internal health control locus. Every fifth parent represented an undifferentiated type - weak or magnifying the impact of others (22.0% and 20.0% respectively). The smallest group of parents (5.3%) belonged to the externally-oriented, strong type. Conclusions. The parents of hospitalized newborns are characterized mainly by high and average levels of stress and low level of severity of health control location within each of its domains. The highest indicator of internal locus control and the influence of others are characterized by parents with low and average levels of stress. The dominant type of locus of health control that characterizes parents is the undifferentiated type – weak and magnifying the impact of others.

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