Incorporating parasite systematics in comparative analyses of variation in spleen mass and testes sizes of rodents

Parasitology ◽  
2011 ◽  
Vol 138 (13) ◽  
pp. 1804-1814 ◽  
Author(s):  
NICOLAS PONLET ◽  
KITIPONG CHAISIRI ◽  
JULIEN CLAUDE ◽  
SERGE MORAND

SUMMARYParasite diversity is hypothesized to act on host life-history traits through investment in immunity. In order to incorporate the diversity of the parasite community that an individual host or a host species may face, two indices can be used: Taxonomic Species Richness and Taxonomic Entropy, where the taxonomic information is incorporated with the taxonomic weight. We tested whether these indices correlate with several morphological traits potentially implicated in immune defence and in reproduction, using data on gastrointestinal helminths and their rodent hosts sampled in Southeast Asia. We found no relationship between parasite diversity indices and either spleen mass or testes size at the intraspecific level, i.e. at the level of individuals. At the interspecific level, we found no relationship between the parasite diversity indices and testes size. However, we found that female spleen mass is significantly influenced by the specific species richness of parasites, whereas male spleen mass is influenced by individual mean parasite diversity indices. We concluded that female spleen mass may have evolved in response to gastrointestinal helminth pressure acting at species levels, while in males, the individual spleen mass could be constrained by other factors, such as the blood storage function of the spleen.

2021 ◽  
Vol 51 (2) ◽  
pp. 122-128
Author(s):  
Ivanildo Amanajás BRITO-JUNIOR ◽  
Marcos TAVARES-DIAS

ABSTRACT Brachyplatystoma vaillantii is a large migratory catfish widely distributed in the Amazon basin, but its parasitic fauna is still poorly known. As it is an important fishery resource in the region of the Amazonas River estuary, the aim of this study was to investigate the parasite community in B. vaillantii from a tributary of the Amazonas River estuary system, in Brazil. We examined 31 juvenile fish, of which 80.6% were parasitized, and a total of 586 parasites were collected. We identified Dermidospermus brachyplastystimae and Dermidospermus araguiensis (Monogenea), Genarchella genarchella (Digenea), Harriscolex piramutab (Cestoda), Pseudoterranova sp. (Nematoda), Ergasilus xinguensis (Crustacea) and mites (Acarina). The dominance was of Pseudoterranova sp. larvae. The parasite community of B. vaillantii was composed of low values of species richness (2.0 ± 1.4), evenness (0.18 ± 0.21) and diversity (0.32 ± 0.37), with predominance of ectoparasite species with low prevalence, low abundance and overdispersion. Host body weight was the main correlate of parasite diversity and abundance, and a diet rich in crustaceans and other invertebrates may be important in structuring the parasite community of B. vaillantii. This is the first report of Dermidospermus brachyplastystimae and D. araguiensis, Pseudoterranova sp. and G. genarchella for B. vaillantii.


Author(s):  
Brynne D. Ovalle ◽  
Rahul Chakraborty

This article has two purposes: (a) to examine the relationship between intercultural power relations and the widespread practice of accent discrimination and (b) to underscore the ramifications of accent discrimination both for the individual and for global society as a whole. First, authors review social theory regarding language and group identity construction, and then go on to integrate more current studies linking accent bias to sociocultural variables. Authors discuss three examples of intercultural accent discrimination in order to illustrate how this link manifests itself in the broader context of international relations (i.e., how accent discrimination is generated in situations of unequal power) and, using a review of current research, assess the consequences of accent discrimination for the individual. Finally, the article highlights the impact that linguistic discrimination is having on linguistic diversity globally, partially using data from the United Nations Educational, Scientific and Cultural Organization (UNESCO) and partially by offering a potential context for interpreting the emergence of practices that seek to reduce or modify speaker accents.


1975 ◽  
Vol 34 (03) ◽  
pp. 740-747 ◽  
Author(s):  
C. R. M Prentice ◽  
C. D Forbes ◽  
Sandra Morrice ◽  
A. D McLaren

SummaryBetting odds for possible carriers of haemophilia have been calculated using data derived from normal and known carrier populations. For each possible carrier the concentration of factor VIII-related antigen and factor VIII biological activity was measured and used to determine the probability of the individual being a carrier. The calculations indicated that, of the 32 possible carriers, 11 were likely to be normal (odds of more than 5:1) while 11 were likely to be haemophilia carriers (again odds of more than 5:1).


2018 ◽  
Vol 10 (13) ◽  
pp. 12792-12799
Author(s):  
Anupama Saha ◽  
Susmita Gupta

Aquatic and semiaquatic Hemiptera bugs play significant ecological roles, and they are important indicators and pest control agents.  Little information is currently available concerning its populations in southern Assam.  This study assessed hemipterans in four sites of Sonebeel, the largest wetland in Assam (3458.12 ha at full storage level), situated in Karimganj District.  The major inflow and outflow of the wetland are the rivers Singla and Kachua, respectively (the Kachua drains into the Kushiyara River).  Samples were trapped with pond nets and were seasonally recorded.  This study recorded a total of 28 species of aquatic and semiaquatic hemipterans belonging to 20 genera under nine families.  Population, geographical and environmental data (e.g., rainfall) were used to assess the relative abundance of species, species richness and different diversity indices, and species distribution. 


2014 ◽  
Vol 143 (8) ◽  
pp. 1681-1691 ◽  
Author(s):  
M. E. ARNOLD ◽  
R. J. GOSLING ◽  
F. MARTELLI ◽  
D. MUELLER-DOBLIES ◽  
R. H. DAVIES

SUMMARYThere has been a rapid rise in the prevalence of cases of monophasic Salmonella Typhimurium (mST) in both humans and farm animals, and it has been found in pigs, cattle and poultry. It is therefore vital to have a good understanding of how to efficiently detect infected farms. The objective of this project was to determine sample type sensitivity in the detection of Salmonella to detect infected groups of animals on both pig (breeder, grower and finisher sites) and cattle (beef and dairy) farms, using data collected from a study investigating farms that were positive for mST, and to explore any variation between different age groups and management practices. A Bayesian approach in the absence of a gold standard was adopted to analyse the individual and pooled faecal sample data collected from each epidemiological group on each of the farms. The sensitivity of pooled sampling depended on the prevalence of infection in the group being sampled, with a higher prevalence leading to higher sensitivity. Pooled sampling was found to be more efficient at detecting positive groups of animals than individual sampling, with the probability of a random sample from a group of animals with 5% prevalence testing positive being equal to 15·5% for immature pigs (3·6% for an individual faecal sample, taking into account the sensitivity and infection prevalence), 7·1% for adult pigs (1·2% for individual sampling), 30% for outdoor cattle (2% for individual sampling) and 34% for indoor cattle (1% for individual sampling). The mean prevalence of each epidemiological group was higher in outdoor farms than indoor for both pigs and cattle (mean within-farm prevalence of 29·4% and 38·7% for outdoor pigs and cattle, respectively, compared to 19·8% and 22·1% for indoor pigs and cattle)


Weed Science ◽  
2007 ◽  
Vol 55 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Lynn M. Sosnoskie ◽  
Edward C. Luschei ◽  
Mark A. Fanning

The importance of managing weeds in seminatural habitats that are adjacent to farm fields is unclear. Weedy-margin vegetation may harbor pests or pathogens and may ALSo serve as source populations for ongoing immigration of weeds into the field. It is ALSo possible, however, that margin vegetation provides habitat for organisms that consume weed seeds or suppress the likelihood of pest or pathogen outbreak. We examined the nature of margin habitat using spatial-scaling of Weed-Species richness as an ecological assay. In 2003, we recorded the occurrence of weedy species along the perimeters of 63 fields in Wisconsin. The fields were distributed within six counties that differed in topography, geological history, local climate, and soil type and which spanned the range of variability in the agricultural landscape. We identified seven habitats that differed in geology and land use. The relationship between species richness and margin class was estimated using an analog of the power law. Additionally, we investigated broadscale correlates of habitat heterogeneity at the field level, using a modeling strategy that included additional explanatory factors logically connected to plant diversity. Using a model-confrontation approach, the survey supported the inclusion of two topographical diversity indices, elevation gradient and a field-shape index, into our model. Our broadscale survey provides information on one of a suite of important considerations needed to make decisions about the importance of managing weeds in field margins.


2017 ◽  
Vol 39 (7) ◽  
pp. 1770-1796 ◽  
Author(s):  
Justin J. Nelson ◽  
Jeremy E. Uecker

Using data from the 2014 Baylor Religion Survey, we examine the relationship between various aspects of religion and parenting satisfaction. Results confirm prior research findings that personal religiosity is positively associated with parenting satisfaction. We also find that religious heterogamy among couples is associated with lower odds of being a satisfied parent. Furthermore, parents who view their parenting as holy or sacred have much higher odds of reporting being satisfied as parents, and the observed relationships between religiosity and parenting satisfaction at both the individual and couple levels are no longer statistically significant in models controlling for parenting sanctification. The religiously unaffiliated have higher odds than evangelical Protestants of having high parenting satisfaction, suggesting the possible presence of parenting pressures within religious communities with a strong emphasis on family life.


2012 ◽  
Vol 42 (3) ◽  
pp. 457-487 ◽  
Author(s):  
Regina Madalozzo ◽  
Carolina Flores Gomes

Consensual union, also known as cohabitation, has become more frequent in recent decades in Brazil and many other countries. In this context, some studies have analyzed the impact of marriage on women's wages. This article analyzes the effects of marital status on Brazilian women's wages by specifically investigating the individual characteristics of these effects using data from the 2000 Brazilian Census Database. This study concludes that wages differ by up to 15 per cent between married and single women and up to 3 per cent between married and cohabiting women.


2015 ◽  
Vol 27 (1) ◽  
pp. 3-19 ◽  
Author(s):  
Masataka Taguri ◽  
John Featherstone ◽  
Jing Cheng

In many health studies, researchers are interested in estimating the treatment effects on the outcome around and through an intermediate variable. Such causal mediation analyses aim to understand the mechanisms that explain the treatment effect. Although multiple mediators are often involved in real studies, most of the literature considered mediation analyses with one mediator at a time. In this article, we consider mediation analyses when there are causally non-ordered multiple mediators. Even if the mediators do not affect each other, the sum of two indirect effects through the two mediators considered separately may diverge from the joint natural indirect effect when there are additive interactions between the effects of the two mediators on the outcome. Therefore, we derive an equation for the joint natural indirect effect based on the individual mediation effects and their interactive effect, which helps us understand how the mediation effect works through the two mediators and relative contributions of the mediators and their interaction. We also discuss an extension for three mediators. The proposed method is illustrated using data from a randomized trial on the prevention of dental caries.


Author(s):  
Joshua Simmons ◽  
Kristen Splinter

Physics-based numerical models play an important role in the estimation of storm erosion, particularly at beaches for which there is little historical data. However, the increasing availability of pre-and post-storm data for multiple events and at a number of beaches around the world has opened the possibility of using data-driven approaches for erosion prediction. Both physics-based and purely data-driven approaches have inherent strengths and weaknesses in their ability to predict storm-induced erosion. It is vital that coastal managers and modelers are aware of these trade-offs as well as methods to maximise the value from each modelling approach in an increasingly data-rich environment. In this study, data from approximately 40 years of coastal monitoring at Narrabeen-Collaroy Beach (SE Australia)has been used to evaluate the individual performance of the numerical erosion models SBEACH and XBeach, and a data-driven modelling technique. The models are then combined using a simple weighting technique to provide a hybrid estimate of erosion.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/v53dZiO8Y60


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