GENETIC COMPONENTS FROM FULL, HALF AND QUARTER DIALLELS FOR THE CULTIVATED STRAWBERRY

1971 ◽  
Vol 13 (3) ◽  
pp. 515-521 ◽  
Author(s):  
R. Watkins ◽  
L. P. S. Spangelo

It is predicted chat satisfactory estimates of genetic variance parameters could be obtained from quarter diallels at a considerable reduction in the cost compared to obtaining similar information from full diallels. It is also predicted that, for breeding procedures designed to exploit all the genetic variance, estimates of genetic progress obtained from half and quarter diallels would be almost identical to those obtained from full diallels.No genetic progress was indicated for strawberry yield for any reasonable selection intensity when only the additive variance was exploited.It is suggested that long-term genetic progress for an economic complex of characters may be obtained by exploiting major gene differences following classical Mendelian principles and using the resulting selections as one source of parents for crosses designed to exploit all the genetic variance – additive, dominant and epistatic.

Author(s):  
Bruce Walsh ◽  
Michael Lynch

In a large population in the absence of new mutation, selection is expected to eventually drive all of the additive-genetic variance in a trait toward zero, resulting in a selection limit. This chapter examines the underlying population-genetics of such a limit, how it is estimated, and reviews the actual nature of limits observed in artificial selection experiments. It also examines the conditions under which a major gene is more important than polygenic response.


2016 ◽  
Author(s):  
Simon K. G. Forsberg ◽  
Joshua S. Bloom ◽  
Meru J. Sadhu ◽  
Leonid Kruglyak ◽  
Örjan Carlborg

Experiments in model organisms report abundant genetic interactions underlying biologically important traits, whereas quantitative genetics theory predicts, and data support, that most genetic variance in populations is additive. Here we describe networks of capacitating genetic interactions that contribute to quantitative trait variation in a large yeast intercross population. The additive variance explained by individual loci in a network is highly dependent on the allele frequencies of the interacting loci. Modeling of phenotypes for multi-locus genotype classes in the epistatic networks is often improved by accounting for the interactions. We discuss the implications of these results for attempts to dissect genetic architectures and to predict individual phenotypes and long-term responses to selection.


Phlebologie ◽  
2010 ◽  
Vol 39 (03) ◽  
pp. 133-137
Author(s):  
H. Partsch

SummaryBackground: Compression stockings are widely used in patients with varicose veins. Methods: Based on published literature three main points are discussed: 1. the rationale of compression therapy in primary varicose veins, 2. the prescription of compression stockings in daily practice, 3. studies required in the future. Results: The main objective of prescribing compression stockings for patients with varicose veins is to improve subjective leg complaints and to prevent swelling after sitting and standing. No convincing data are available concerning prevention of progression or of complications. In daily practice varicose veins are the most common indication to prescribe compression stockings. The compliance depends on the severity of the disorder and is rather poor in less severe stages. Long-term studies are needed to proof the cost-effectiveness of compression stockings concerning subjective symptoms and objective signs of varicose veins adjusted to their clinical severity. Conclusion: Compression stockings in primary varicose veins are able to improve leg complaints and to prevent swelling.


2017 ◽  
pp. 34-47
Author(s):  
Hoi Le Quoc ◽  
Nam Pham Xuan ◽  
Tuan Nguyen Anh

The study was targeted at developing a methodology for constructing a macroeconomic performance index at a provincial level for the first time in Vietnam based on 4 groups of measurements: (i) Economic indicators; (ii) oriented economic indicators; (iii) socio-economic indicators; and (iv) economic - social – institutional indicators. Applying the methodology to the 2011 - 2015 empirical data of all provinces in Vietnam, the research shows that the socio-economic development strategy implemented by those provinces did not provide balanced outcomes between growth and social objectives, sustainability and inclusiveness. Many provinces focused on economic growth at the cost of structural change, equality and institutional transformation. In contrast, many provinces were successful in improving equality but not growth. Those facts threaten the long-term development objectives of the provinces.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mihály Racsmány ◽  
Dorottya Bencze ◽  
Péter Pajkossy ◽  
Ágnes Szőllősi ◽  
Miklós Marián

AbstractOne of the greatest commonplaces in memory research is that context improves recall and enhances or leaves recognition intact. Here we present results which draw attention to the fact that the reappearance of irrelevant and unattended background contexts of encoding significantly impairs memory discrimination functions. This manuscript presents the results of two experiments in which participants made indoor/outdoor judgements for a large number of object images presented together with individual, irrelevant and presumably unattended background scenes. On a subsequent unexpected recognition test participants saw the incidentally encoded target objects, visually similar lures or new foil objects on the same or new background scenes. Our results showed that although the reappearance of the background scene raised the hit rate for target objects, it decreased mnemonic discrimination, a behavioral score for pattern separation, a hippocampal function that is affected in early dementia. Furthermore, the presence of the encoded background scene at the recognition test increased the false recognition of lure objects, even when participants were explicitly instructed to neglect the context scene. Altogether these results gave evidence that if context increases recognition hits for target memories, it does so at the cost of increasing false recognition and diminished discriminability for similar information.


2021 ◽  
pp. 227853372110083
Author(s):  
Smita Mukherjee ◽  
Zubin R. Mulla

We examine the cost of leaders changing between empowering and directive leadership styles on team outcomes. In a laboratory experiment, we collected data from 240 participants in 80 teams. Confederates enacted different leadership styles and led teams of participants in performing a series of tasks. When leaders changed their style from directive to empowering, teams took time to respond in terms of higher satisfaction with leader and affective commitment. However, when leaders changed their style from empowering to directive, the deterioration of satisfaction with leader and reduction in affective commitment were immediate. Moreover, teams of leaders who had been consistently directive showed higher affective commitment as compared to teams of leaders who had a history of being empowering but later shifted to being directive. First time managers can get inputs on how they should enact their leadership style and be aware that switching between styles may impose long-term costs on the team’s affective commitment and satisfaction with the leader.


2021 ◽  
Vol 10 (8) ◽  
pp. 523
Author(s):  
Nicholus Mboga ◽  
Stefano D’Aronco ◽  
Tais Grippa ◽  
Charlotte Pelletier ◽  
Stefanos Georganos ◽  
...  

Multitemporal environmental and urban studies are essential to guide policy making to ultimately improve human wellbeing in the Global South. Land-cover products derived from historical aerial orthomosaics acquired decades ago can provide important evidence to inform long-term studies. To reduce the manual labelling effort by human experts and to scale to large, meaningful regions, we investigate in this study how domain adaptation techniques and deep learning can help to efficiently map land cover in Central Africa. We propose and evaluate a methodology that is based on unsupervised adaptation to reduce the cost of generating reference data for several cities and across different dates. We present the first application of domain adaptation based on fully convolutional networks for semantic segmentation of a dataset of historical panchromatic orthomosaics for land-cover generation for two focus cities Goma-Gisenyi and Bukavu. Our experimental evaluation shows that the domain adaptation methods can reach an overall accuracy between 60% and 70% for different regions. If we add a small amount of labelled data from the target domain, too, further performance gains can be achieved.


Genetics ◽  
1996 ◽  
Vol 144 (4) ◽  
pp. 1961-1974 ◽  
Author(s):  
Ming Wei ◽  
Armando Caballero ◽  
William G Hill

Formulae were derived to predict genetic response under various selection schemes assuming an infinitesimal model. Account was taken of genetic drift, gametic (linkage) disequilibrium (Bulmer effect), inbreeding depression, common environmental variance, and both initial segregating variance within families (σAW02) and mutational (σM2) variance. The cumulative response to selection until generation t(CRt) can be approximated asCRt≈R0[t−β(1−σAW∞2σAW02)t24Ne]−Dt2Ne,where Ne is the effective population size, σAW∞2=NeσM2 is the genetic variance within families at the steady state (or one-half the genic variance, which is unaffected by selection), and D is the inbreeding depression per unit of inbreeding. R  0 is the selection response at generation 0 assuming preselection so that the linkage disequilibrium effect has stabilized. β is the derivative of the logarithm of the asymptotic response with respect to the logarithm of the within-family genetic variance, i.e., their relative rate of change. R  0 is the major determinant of the short term selection response, but σM2, Ne and β are also important for the long term. A selection method of high accuracy using family information gives a small Ne and will lead to a larger response in the short term and a smaller response in the long term, utilizing mutation less efficiently.


2000 ◽  
Vol 3 (1) ◽  
Author(s):  
Matthew Eichner ◽  
Mark McClellan ◽  
David A. Wise

We are engaged in a long-term project to analyze the determinants of health care cost differences across firms. An important first step is to summarize the nature of expenditure differences across plans. The goal of this article is to develop methods for identifying and quantifying those factors that account for the wide differences in health care expenditures observed across plans.We consider eight plans that vary in average expenditure for individuals filing claims, from a low of $1,645 to a high of $2,484. We present a statistically consistent method for decomposing the cost differences across plans into component parts based on demographic characteristics of plan participants, the mix of diagnoses for which participants are treated, and the cost of treatment for particular diagnoses. The goal is to quantify the contribution of each of these components to the difference between average cost and the cost in a given firm. The demographic mix of plan enrollees accounts for wide differnces in cost ($649). Perhaps the most noticeable feature of the results is that, after adjusting for demographic mix, the difference in expenditures accounted for by the treatment costs given diagnosis ($807) is almost as wide as the unadjusted range in expenditures ($838). Differences in cost due to the different illnesses that are treated, after adjusting for demographic mix, also accounts for large differences in cost ($626). These components of cost do not move together; for example, demographic mix may decrease expenditure under a particular plan while the diagnosis mix may increase costs.Our hope is that understanding the reasons for cost differences across plans will direct more focused attention to controlling costs. Indeed, this work is intended as an important first step toward that goal.


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