scholarly journals Heterozygosity and growth in the marine bivalve Spisula ovalis: testing alternative hypotheses

1997 ◽  
Vol 70 (3) ◽  
pp. 215-223 ◽  
Author(s):  
PATRICE DAVID ◽  
BERNARD DELAY ◽  
PHILIPPE JARNE
Keyword(s):  
Age And Growth ◽  
Null Alleles ◽  
Marine Bivalve ◽  
Multilocus Genotype ◽  
Simple Explanation ◽  
Specific Effects ◽  
Marine Bivalves ◽  
Alternative Hypotheses ◽  
Mean Fitness ◽  
The Relationship

Allozyme-associated heterosis has been repeatedly observed in marine bivalves, but its genetic origin remains debatable. A simple explanation is direct overdominance at the enzyme loci scored. An alternative is associative overdominance due to partial inbreeding, affecting the whole genome. The two hypotheses yield different predictions concerning (i) locus-specific effects, (ii) the relationship between heterozygosity and the variance in fitness, and (iii) the expected form of the relationship between the multilocus genotype and mean fitness. The relationship between heterozygosity and growth, a component of fitness, is here analysed in Spisula ovalis (1669 individuals, 9 loci), using statistical models designed to test these predictions. In contrast to most other bivalves, S. ovalis shells display clear annual growth lines allowing accurate quantification of individual age and growth. Our results show (i) that there is no evidence for locus-specific effects, (ii) that the variance in growth decreases significantly when heterozygosity increases, and (iii) that growth is better predicted by a genetic variable optimized for inbreeding than by a variable optimized for overdominance. In addition, the heterozygosity–growth relationship displays a significant variation among annual cohorts, being more pronounced in young cohorts. Although the need to pool alleles and the occurrence of null alleles may limit the efficiency of some of the models used (especially for result (iii)), our results suggest that the heterozygosity–growth relationship is due to inbreeding effects.

scholarly journals Cognitive Vulnerabilities to Anxiety

2019 ◽  
Vol 28 (2) ◽  
pp. 419-440
Author(s):  
Mirjana Sučević ◽  
Ana Kurtović
Keyword(s):  
Risk Factor ◽  
Social Anxiety ◽  
Anxiety Sensitivity ◽  
Intolerance Of Uncertainty ◽  
Self Esteem ◽  
Anxiety Symptoms ◽  
Cognitive Vulnerabilities ◽  
Specific Effects ◽  
Social Concerns ◽  
The Relationship

The purpose of the study was to examine the effects of personality, anxiety sensitivity, intolerance of uncertainty and self-esteem on different anxiety symptoms. A total of 436 university students completed measures of personality, anxiety sensitivity, intolerance of uncertainty, self-esteem, and symptoms of panic, worry and social anxiety. Results have shown that neuroticism, conscientiousness and psychological concerns (anxiety sensitivity) predict symptoms of panic and that psychological concerns mediate the relationship between neuroticism and panic. Worry was predicted by neuroticism, prospective and inhibitory intolerance of uncertainty and self-liking, with intolerance of uncertainty mediating between neuroticism and worry. Finally, neuroticism, openness to experiences and extraversion, as well as social concerns (anxiety sensitivity), inhibitory intolerance of uncertainty and self-liking predicted social anxiety. Social concerns, inhibitory intolerance of uncertainty and self-liking mediated the effects of neuroticism and extraversion on social anxiety. Results offer support to neuroticism being a universal risk factor and anxiety sensitivity, intolerance of uncertainty and self-esteem having specific effects on anxiety symptoms.

scholarly journals A sexually-dimorphic murine model of IUGR induced by embryo transfer

Reproduction ◽  
2020 ◽  
Author(s):  
Harleen Kaur ◽  
Alison S. Care ◽  
Rebecca L Wilson ◽  
Sandra G Piltz ◽  
Paul Q Thomas ◽  
...  
Keyword(s):  
Litter Size ◽  
Placental Weight ◽  
Specific Gene ◽  
Sexually Dimorphic ◽  
Risk Of Death ◽  
Specific Effects ◽  
Size Number ◽  
Implantation Sites ◽  
Cd1 Mice ◽  
The Relationship

Animal models are needed to develop interventions to prevent or treat intrauterine growth restriction (IUGR). Fetal growth rates and effects of in utero exposures differ between sexes, but little is known about sex-specific effects of increasing litter size. We established a murine IUGR model using pregnancies generated by multiple embryo transfers, and evaluated sex-specific responses to increasing litter size. CBAF1 embryos were collected at gestation day 0.5 (GD0.5) and 6, 8, 10 or 12 embryos were transferred into each uterine horn of pseudo-pregnant female CD1 mice (n=32). Fetal and placental outcomes were measured at GD18.5. In the main experiment fetuses were genotyped (Sry) for analysis of sex-specific outcomes. The number of implantation sites (P=0.033) and litter size (number of fetuses, P=0.008) correlated positively with number of embryos transferred, while placental weight correlated negatively with litter size (both P<0.01). The relationship between viable litter size and fetal weight differed between sexes (interaction P=0.002), such that fetal weights of males (P=0.002), but not females (P=0.233), correlated negatively with litter size. Placental weight decreased with increasing litter size (P<0.001) and was lower in females than males (P=0.020). Our results suggest that male fetuses grow as fast as permitted by nutrient supply, whereas the female maintains placental reserve capacity. This strategy reflecting sex-specific gene expression is likely to place the male fetus at greater risk of death in the event of a “second hit”.

scholarly journals Genetic status of Norway spruce (Picea abies) breeding populations for northern Sweden

2013 ◽  
Vol 62 (1-6) ◽  
pp. 127-136 ◽  
Author(s):  
P. Androsiuk ◽  
A. Shimono ◽  
J. Westin ◽  
D. Lindgren ◽  
A. Fries ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Norway Spruce ◽  
Population Differentiation ◽  
Distinct Group ◽  
Null Alleles ◽  
Multilocus Genotype ◽  
Northern Sweden ◽  
High Genetic Diversity ◽  
Breeding Populations ◽  
Ssr Loci

AbstractEfficient use of any breeding resources requires a good understanding of the genetic value of the founder breeding materials for predicting the gain and diversity in future generations. This study evaluates the distribution of genetic variation and level of relatedness among and within nine breeding populations of Norway spruce for Northern Sweden using nuclear microsatellite markers. A sample set of 456 individuals selected from 140 stands were genotyped with 15 SSR loci. Over all loci each individual was identified with unique multilocus genotype. High genetic diversity (average He=0.820) and low population differentiation (FST=0.0087) characterized this material. Although low in FST, the two northernmost populations were clustered as a distinct group diverged from the central populations. The population differentiation pattern corresponds well with the post glacial migration history of Norway spruce and the current gene flow and human activity in the region. The average inbreeding coefficient was 0.084 after removal loci with high frequency of null alleles. The estimated relatedness of the trees gathered in the breeding populations was very low (average kinship coefficient 0.0077) and not structured. The high genetic variation and low and not structured relatedness between individuals found in the breeding populations confirm that the Norway spruce breeding stock for northern Sweden represent valuable genetic resources for both long-term breeding and conservation programs.

Heteroskedasticity between GNSS time-series repeatabilities and noise magnitudes

2021 ◽  
Author(s):  
Huseyin Duman ◽  
Doğan Uğur Şanlı
Keyword(s):  
Time Series ◽  
Linear Equations ◽  
Test Methods ◽  
P Value ◽  
P Values ◽  
Modeling Errors ◽  
Alternative Hypotheses ◽  
The Relationship ◽  
Baseline Component ◽  
Gnss Time Series

&lt;p&gt;In the analysis of GNSS time series, when the sampling frequency and time-series lengths are almost identical, it is possible to highlight a linear relationship between the series repeatabilities (i.e. WRMS) and noise magnitudes. In the literature, linear equations as a function of WRMSs allowed many researchers to estimate the noise magnitudes. However, this was built upon homoskedasticity. We experienced the higher WRMSs, the more erroneous analysis results using the noise magnitudes from the linear equations stated. We hence studied whether or not homoscedasticity clearly describes the modeling errors. To test that, we used the published results of GPS baseline components from the previous work in the literature and realized here that each component forms part of the totality. We introduced all baseline component results as a whole into statistical analysis to check heteroskedasticity. We established null and alternative hypotheses on the residuals which are homoscedastic (H0) or heteroskedastic (HA). We adopted both the Breusch-Pagan test and the Goldfeld-Quandt test to prove heteroskedasticity and obtained p-values for both methods. The p-value, which is the probability measure, equals to almost zero for both test methods, that is, we fail to accept the null hypothesis. Consequently, we can confidently state that the relationship between the WRMSs and the noise magnitudes is heteroskedastic.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords:&lt;/strong&gt; Noise magnitudes, repeatabilities, heteroskedasticity, time-series analysis&lt;/p&gt;

Dominance-related foraging in female domesticated canaries under laboratory conditions

2004 ◽  
Vol 82 (8) ◽  
pp. 1246-1250 ◽  
Author(s):  
M Parisot ◽  
L Nagle ◽  
E Vallet ◽  
M Kreutzer
Keyword(s):  
Laboratory Experiment ◽  
Social Status ◽  
Environmental Conditions ◽  
Foraging Behaviour ◽  
Unanswered Question ◽  
Serinus Canaria ◽  
Laboratory Conditions ◽  
Pair Bonds ◽  
Alternative Hypotheses ◽  
The Relationship

Many experiments have tested the foraging behaviours of birds relative to their social status. However, results are still not completely clear about the relationship between foraging behaviour and social status in birds. Some studies have shown that dominants use subordinates as food finders, while others show the opposite. Whether dominants search by themselves or wait to exploit the findings of a subordinate is still an unanswered question. For testing these alternative hypotheses, we carried out a laboratory experiment that used female common domesticated canaries, Serinus canaria (L., 1758). We used strict female flocks to avoid any bias based on pair bonds. We looked at the foraging behaviours of females relative to their social status using a foraging board. Our results showed that dominant females behaved as their own food finder. They began searching in the first position and had greater re-search behaviours, which allowed them to find seeds more rapidly than subordinates. Our study showed that foraging behaviour of dominants may be independent of the activities of subordinates. Our results also showed that there was no difference between the number of attacks received by dominants and subordinates when they were on the foraging board, which suggests that subordinates accessed the foraging board less frequently to avoid competition with dominants. We also suggest that environmental conditions may be one explanation for the differences observed among the different studies.

scholarly journals Genetic Diversity and Origins of the Homoploid-Type HybridPhytophthora ×alni

2016 ◽  
Vol 82 (24) ◽  
pp. 7142-7153 ◽  
Author(s):  
Jaime Aguayo ◽  
Fabien Halkett ◽  
Claude Husson ◽  
Zoltán Á. Nagy ◽  
András Szigethy ◽  
...  
Keyword(s):  
Parental Species ◽  
Temporal Structure ◽  
Plant Diseases ◽  
Multilocus Genotype ◽  
Disease Emergence ◽  
Genetic Characteristics ◽  
Content Type ◽  
Geographic Structure ◽  
Historical Processes ◽  
The Relationship

ABSTRACTAssessing the process that gives rise to hybrid pathogens is central to understanding the evolution of emerging plant diseases.Phytophthora ×alni, a pathogen of alder, results from the homoploid hybridization of two related species,Phytophthora uniformisandPhytophthora×multiformis. Describing the genetic characteristics ofP. ×alnishould help us understand how reproductive mechanisms and historical processes shaped the population structure of this emerging hybrid pathogen. The population genetic structure ofP. ×alniand the relationship with its parental species were investigated using 12 microsatellites and one mitochondrial DNA (mtDNA) marker on a European collection of 379 isolates. Populations ofP. ×alniwere dominated by one multilocus genotype (MLG). The frequency of this dominant MLG increased after the disease emergence together with a decline in diversity, suggesting that it was favored by a genetic mechanism such as drift or selection. Combined microsatellite and mtDNA results confirmed thatP. ×alnioriginated from multiple hybridization events that involved different genotypes of the progenitors. Our detailed analyses point to a geographic structure that mirrors that observed forP. uniformisin Europe. The study provides more insights on the contribution ofP. uniformis, an invasive species in Europe, to the emergence ofPhytophthora-induced alder decline.IMPORTANCEOur study describes an original approach to assess the population genetics of polyploid organisms using microsatellite markers. By studying the parental subgenomes present in the interspecific hybridP. ×alni, we were able to assess the geographical and temporal structure of European populations of the hybrid, shedding new light on the evolution of an emerging plant pathogen. In turn, the study of the parental subgenomes permitted us to assess some genetic characteristics of the parental species ofP. ×alni,P. uniformis, andP. ×multiformis, which are seldom sampled in nature. The subgenomes found inP. ×alnirepresent a picture of the “fossilized” diversity of the parental species.

Conceptual transfer: Crosslinguistic effects in categorization and construal

2010 ◽  
Vol 14 (1) ◽  
pp. 1-8 ◽  
Author(s):  
SCOTT JARVIS
Keyword(s):  
Cognitive Development ◽  
Positive Effects ◽  
Specific Effects ◽  
Language And Cognition ◽  
Conceptual Transfer ◽  
The Relationship

Research on the relationship between language and cognition in bilinguals has often focused on general effects that are common to bilinguals of all language backgrounds, such as the positive effects of bilingualism in various areas of cognitive development (e.g., Bialystok, 2005; Karmiloff-Smith, 1992). However, there are also language-specific effects in the relationship between language and cognition in bilinguals that emerge in the form of cross-linguistic influence and, in many cases, these cross-linguistic effects do not appear to be confined to purely linguistic (e.g., phonological, morphological, syntactic, semantic) phenomena. For example, bilinguals’ choice of words for referring to objects and actions, as well as their choice of syntactic and discursive structures for referring to events and situations, often reflect ways of conveying meaning and intentions that are specific to particular language backgrounds.

scholarly journals Primary Headache in Yemen: Prevalence and Common Medications Used

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Salah A. Abdo ◽  
Mohammed Amood AL-Kamarany ◽  
Karem H. Alzoubi ◽  
Mohamed T. Al-Maktari ◽  
Abdulrhman H. Al-Baidani
Keyword(s):  
Diclofenac Sodium ◽  
Case Series ◽  
Primary Headache ◽  
Tension Type Headache ◽  
Primary Headaches ◽  
Simple Explanation ◽  
Cross Sectional ◽  
High Prevalence ◽  
Type Headache ◽  
The Relationship

Background and Objective. Primary headaches is a major medical concern in certain Arabic countries, for example Oman, Jordan, and Qatar. This study was aimed at increasing understanding of the prevalence of headache in Arabic countries and identifying common medications used for treatment because of the lack of research done in this field in Yemen.Methods. This is a cross-sectional observational study conducted by recruiting case-series of adults and elderly who have primary headache within the age group from 18 to 85 years. 12640 subjects received a simple explanation for the aim of the study as ethical issue. The subjects were allowed to complete a self-conducted screening questionnaire. The data were diagnosed according to the International Headache Society’s diagnostic criteria (2004).Results. The results showed that 76.5% of the primary headache is prevalent at least once per year, 27.1% of the tension type headache (TTH) was the maximum percentage of type of headache, and 14.48% of the migraine headache (MH) was the minimum percentage. On the other hand, the relationship between the primary headache and age of subjects was statistically significant (P<0.05), while between primary headache and sex was not (P>0.05). In addition, 70.15% of the subjects said that headache attacks affected their activity of daily livings (ADL). 62.26% of the subjects used the medications without medical advice regarding their headache. 37.73% of the subjects relied on medical professionals (physicians and pharmacist) regarding analgesics use. The most common agent used among the medications was paracetamol (38.4%). Others included ibuprofen, aspirin, diclofenac sodium, naproxen, mefenamic acid, ergotamine and (11.45%) were unknown agents.Conclusion. We concluded that absence of health attention from the Yemeni Community and education from the health system in the country regarding analgesics use and their potential risk led to abuse of such medications and could be a reason beyond high prevalence of headache in Yemen.

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