scholarly journals Sexual antagonism in haplodiploids

2021 ◽  
Author(s):  
Thomas James Hitchcock ◽  
Andy Gardner ◽  
Laura Ross
Keyword(s):  
Resource Competition ◽  
Sexual Antagonism ◽  
Paternal Genome ◽  
Male Dispersal ◽  
Relative Value ◽  
Evolutionary Genetic ◽  
Sib Mating ◽  
Almost All ◽  
Sizeable Minority ◽  
Mode Of Inheritance

Females and males may face different selection pressures, such that alleles conferring a benefit in one sex may be deleterious in the other. Such sexual antagonism has received a great deal of theoretical and empirical attention, almost all of which has focused on diploids. However, a sizeable minority of animals display an alternative haplodiploid mode of inheritance, encompassing both arrhenotoky, whereby males develop from unfertilized eggs, and paternal genome elimination (PGE), whereby males receive but do not transmit a paternal genome. Alongside unusual genetics, haplodiploids often exhibit social ecologies that modulate the relative value of females and males. Here we develop a series of evolutionary-genetic models of sexual antagonism for haplodiploids, incorporating details of their molecular biology and social ecology. We find that: 1) PGE promotes female-beneficial alleles more than arrhenotoky, and to an extent determined by the timing of elimination - and degree of silencing of - the paternal genome; 2) sib-mating relatively promotes female-beneficial alleles, as do other forms of inbreeding, including limited male-dispersal, oedipal-mating, and the pseudo-hermaphroditism of Icerya purchasi; 3) resource competition between related females relatively inhibits female-beneficial alleles; and 4) sexual antagonism foments conflicts between parents and offspring, endosymbionts and hosts, and maternal-origin and paternal-origin genes.

scholarly journals POTENTIAL OF MULTI-TEMPORAL UAV-BORNE LIDAR IN ASSESSING EFFECTIVENESS OF SILVICULTURAL TREATMENTS

2017 ◽  
Vol XLII-2/W6 ◽  
pp. 393-397 ◽  
Author(s):  
U. Vepakomma ◽  
D. Cormier
Keyword(s):  
Resource Competition ◽  
Distribution Patterns ◽  
Forest Stand ◽  
Partial Cutting ◽  
Silvicultural Treatments ◽  
Short Period ◽  
The Difference ◽  
Silvicultural System ◽  
Individual Trees ◽  
Almost All

Silvicultural treatments are practiced to control resource competition and direct forest stand development to meet management objectives. Effective tracking of thinning and partial cutting treatments help in timely mitigation and ensuring future stand productivity. Based on a study conducted in autumn 2015, our findings in a white pine dominant forest stand in Petawawa (Ontario, Canada) showed that almost all individual trees were detectable, structure of individual trees and undergrowth was well pronounced and underlying terrain below dense undisturbed canopy was well captured with UAS based Riegl Vux-1 lidar even at a range of 150 m. Thereafter, the site was re-scanned the following summer with the same system. Besides understanding the difference in distribution patterns due to foliage conditions, co-registering the two datasets, in the current study, we tested the potential of quantifying effectiveness of a partial cutting silvicultural system especially in terms of filling of 3D spaces through vertical or lateral growth and mortality in a very short period of time.

scholarly journals Über 27 Sippen mit infantiler amaurotischer Idiotie (Tay-Sachs)

1955 ◽  
Vol 3 (3) ◽  
pp. 331-364 ◽  
Author(s):  
E. Hanhart
Keyword(s):  
Clinical Picture ◽  
Jewish Population ◽  
Present Author ◽  
Autosomal Recessive ◽  
Reduction Method ◽  
Parental Consanguinity ◽  
Modifying Genes ◽  
Niemann Pick ◽  
Almost All ◽  
Mode Of Inheritance

SUMMARYThis paper is based on 45 cases in 27 families, all of which have been studied in Children Hospitals. In Switzerland almost all cases ofinfantile amaurotic idiocy (Tay-Sachs)have probably been collected, so that the stated 13 primary and 14 secondary cases may allow an estimation of the frequency of this character, which seems to oscillate temporarily. In the last 10 years no new cases have been observed.All 24 autochthonus Swiss cases are from non-Jewish, mostly rural origin, in which Eastern Jews are not to be supposed as ascendants.Our in all 27 families with TS make Slome's statistic of Jewish and non-Jewish cases in literature much more significant; the incidence of parental consanguinity is, as a matter of fact, nearly twice as high in families with non-Jewish origin.There is no evidence of a milder and longer course of TS in non-Jewish families.The mode of inheritance is, according to Slome,monohybrid autosomal recessive, though in remarkably many sibships there is an accumulation of cases. The reduction method, however, gives a percentage of 28,3 ± 6,2, coming quite near to the expectation of the Mendelian quarter.The penetrance of the character is total, the expressivity generally very equal, with only a few deviations from the well—known clinical picture of TS.The interfamiliar and intrafamiliar variability therefore is small. In not even one of the families studied have there been found other forms of lipoidosis, principally no cases ofsplenohepatomegalia Niemann-Pick. All available respective cases in Switzerland have been collected by the present author and will soon be published in these Acta. In none of these families with M.Niemann-Pickhave cases of M. Tay-Sachs been seen. This fact is liable to prove that these clinically and anatomically very similar conditions derive from independent i. e. different mutations.Modifying genes may account for the incidence of sibships in which all or almost all children died from M. TS.Environmental influences do not seem to favour its manifestations.If in the newer literature from the U.S.A. the Jewish cases of M. TS are still prevalent and if, as we heard, the concomitant manifestations occur fairly often in Israel, the origin may be sought in one at least 200 years old respective mutation in the Jewish population of a relatively restricted White-Russian era.

Development of gynogenetic and parthenogenetic inner cell mass and trophectoderm tissues in reconstituted blastocysts in the mouse.

Development ◽  
1985 ◽  
Vol 90 (1) ◽  
pp. 267-285
Author(s):  
Sheila C. Barton ◽  
Catharine A. Adams ◽  
M. L. Norris ◽  
M. A. H. Surani
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Paternal Genome ◽  
Developmental Potential ◽  
Somite Stage ◽  
Tissue Degeneration ◽  
Equivalent Control ◽  
Complete Failure ◽  
Almost All ◽  
Insight Into

The developmental potential of inner cell mass (ICM) and trophectoderm (TE) derived from parthenogenetic or biparental gynogenetic embryos was examined in reconstituted blastocysts with normal TE or ICM, respectively. The results demonstrate that when a normal ICM was introduced inside a trophectoderm vesicle derived from parthenogenetic or gynogenetic blastocysts, postimplantation development was characterized by the almost complete failure of trophoblast proliferation and without compensating cellular contribution from the normal ICM to the outer trophoblast lineage. Consequently, the normal ICMs also failed to develop adequately and only a few retarded embryos were detected on day 11–12 of pregnancy. In most respects, development of these reconstituted blastocysts resembled that obtained with unoperated gynogenetic and a parthenogenetic blastocyst. By contrast, an ICM from a parthenogenetic or gynogenetic embryo introduced inside a normal trophectoderm vesicle induced substantial proliferation of the trophoblast but again without a detectable cellular contribution from the ICM to the outer trophoblast lineage. However, with the improved development of the trophoblast, both the parthenogenetic and gynogenetic ICMs developed substantially better and without a detectable cellular contribution from the TE to the embryo. Almost all the embryos developed at least up to the 25-somite stage and many of them reached the 30- to 40-somite stage. Some of the most advanced day-11 and -12 gynogenones and parthenogenones yet seen have now been obtained in this way. Nevertheless, all the embryos were still smaller than the equivalent control embryos and showed signs of some tissue degeneration. The yolk sac was also suboptimal with poor blood supply and may need to be improved to obtain further improvement in the development of the embryos. The combined results demonstrate that the trophoblast proliferates very poorly even in the presence of a normal ICM, if the TE tissue lacks a paternal genome. However, ICM tissues which lack a paternal genome can develop to an advanced embryonic stage if they are introduced inside a normal trophectoderm vesicle. The results give further insight into the differential roles of maternal and paternal genomes during development of the embryo and extraembryonic tissues in the mouse.

scholarly journals Competition Drives Group Formation and Reduces Within Nest Relatedness in a Facultatively Social Carpenter Bee

2021 ◽  
Vol 9 ◽  
Author(s):  
Jess L. Vickruck ◽  
Miriam H. Richards
Keyword(s):  
Resource Sharing ◽  
Resource Competition ◽  
Group Formation ◽  
Social Groups ◽  
Fitness Costs ◽  
Short Supply ◽  
Carpenter Bee ◽  
Direct Fitness ◽  
Indirect Fitness ◽  
Almost All

Animals respond to competition among kin for critical breeding resources in two ways: avoidance of direct fitness costs via dispersal of siblings to breed separately, and formation of kin-based societies in which subordinates offset direct fitness costs of breeding competition via altruism and increased indirect fitness. In the facultatively social eastern carpenter bee, nests are a critical breeding resource in perpetually short supply, leading to strong competition among females. Observations of individually marked and genotyped females in conditions of high and low resource competition demonstrate that competition leads to resource sharing and group nesting. However, in contrast to almost all known animal societies, females avoid nesting with relatives, and disperse from their natal nests to join social groups of non-relatives. This is the first example of a structured insect society with cooperation nestmates, the majority of which are unrelated; thus cooperation is more likely based on selection for direct, rather than indirect fitness. By forming social groups of non-kin, females avoid the indirect fitness costs of kin competition among sisters, yet increase their chances of successful reproduction, and thus direct fitness, when forming colonies of non-relatives.

scholarly journals The Framework of Competency Facilities Manager in Pre-Construction Hospital in Malaysia

2020 ◽  
Vol 9 (3) ◽  
pp. 3949-3952
Keyword(s):  
Descriptive Analysis ◽  
Hospital Staff ◽  
Public Hospitals ◽  
Construction Stage ◽  
Relative Value ◽  
Facility Manager ◽  
Hospital Construction ◽  
Questionnaire Method ◽  
Almost All ◽  
The Cost

This paper distinguishes was conducted on the importance of the facility mnager's competence for a complex construction project such as hospital construction. There is thus a need to study the competence of facilities managers at the level of hospital construction. Directly, the involvement of the facility manager at the construction stage can reduce the cost of operating the building. This paper study was carried out using two methods, namely questionnaire method and interview method. The study involved the construction of architects, engineers, quantity surveyors, public hospital staff and facilities managers directly involved in the construction of public hospitals in Malaysia. The data obtained were analyzed using descriptive analysis techniques, relative value index (RII) and analysis using SEM Smart PLS method. The findings found that almost all respondents felt that leadership factors, communication factors, operating and maintenance factors, human factors, property and property management factors, and business preparedness and business balance factors were factors influencing facility manager competence at the construction stage.

scholarly journals Lumpy species coexistence arises robustly in fluctuating resource environments

2017 ◽  
Vol 115 (4) ◽  
pp. 738-743 ◽  
Author(s):  
Athanasia Sakavara ◽  
George Tsirtsis ◽  
Daniel L. Roelke ◽  
Rebecca Mancy ◽  
Sofie Spatharis
Keyword(s):  
Species Coexistence ◽  
Resource Competition ◽  
Dynamic Pattern ◽  
Natural Systems ◽  
Assemblage Organization ◽  
Competitive Species ◽  
Limiting Resources ◽  
Almost All ◽  
Tidal Hydrology ◽  
The Impact

The effect of life-history traits on resource competition outcomes is well understood in the context of a constant resource supply. However, almost all natural systems are subject to fluctuations of resources driven by cyclical processes such as seasonality and tidal hydrology. To understand community composition, it is therefore imperative to study the impact of resource fluctuations on interspecies competition. We adapted a well-established resource-competition model to show that fluctuations in inflow concentrations of two limiting resources lead to the survival of species in clumps along the trait axis, consistent with observations of “lumpy coexistence” [Scheffer M, van Nes EH (2006)Proc Natl Acad Sci USA103:6230–6235]. A complex dynamic pattern in the available ambient resources arose very early in the self-organization process and dictated the locations of clumps along the trait axis by creating niches that promoted the growth of species with specific traits. This dynamic pattern emerged as the combined result of fluctuations in the inflow of resources and their consumption by the most competitive species that accumulated the bulk of biomass early in assemblage organization. Clumps emerged robustly across a range of periodicities, phase differences, and amplitudes. Given the ubiquity in the real world of asynchronous fluctuations of limiting resources, our findings imply that assemblage organization in clumps should be a common feature in nature.

scholarly journals Introgressions of Vitis rotundifolia Michx. to obtain grapevine genotypes with complex resistance to biotic and abiotic stresses

2021 ◽  
Vol 25 (7) ◽  
pp. 693-700
Author(s):  
V. A. Volynkin ◽  
V. V. Likhovskoi ◽  
I. A. Vasylyk ◽  
N. A. Rybachenko ◽  
E. A. Lushchay ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Abiotic Stresses ◽  
Biotic And Abiotic Stresses ◽  
Paternal Genome ◽  
Vitis Rotundifolia ◽  
Maternal Genotype ◽  
The Family ◽  
M 31 ◽  
Almost All ◽  
High Degree

Vitis rotundifolia Michx. is one of the species of the family Vitaceae, with resistance to both biotic and abiotic stresses. The present study reports new scientific knowledge about the inheritance of resistance to downy mildew, powdery mildew and frost by V. vinifera varieties from V. rotundifolia. Recombinant lines of three hybrid populations from the crossing of the maternal genotype ♀M. 31-77-10 with V. rotundifolia hybrids were used as the object of the study. As a result of laboratory screening, more than 40 % of recombinants of the ♀M. 31-77-10× ×[DRX-M5-734+DRX-M5-753+DRX-M5-790] population showed a high degree of frost resistance (–24 °C), while 6 % of transgressive recombinants were characterized by a very high degree of resistance (–27 °С). The maternal genotype ♀M. 31-77-10 does not carry alleles of resistance to powdery mildew at the Run1 locus and in the field suffers from powdery mildew much more than the paternal genotypes. The prevalence of powdery mildew on vegetative organs in the three recombinant populations over the years varies on average between 3.2–17.1, 0.3–17.7 and 0.6–5.2 %, respectively. As a result, almost all recombinant genotypes that received a resistant allele from the paternal genome are highly resistant to powdery mildew.

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

1977 ◽  
Vol 35 ◽  
pp. 590-591
Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Critical Point ◽  
Avena Sativa ◽  
Substantial Improvement ◽  
Fresh Tissue ◽  
Cold Stage ◽  
Critical Point Drying ◽  
Almost All ◽  
Cell Collapse ◽  
Conductive Paint ◽  
Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

Electron microscopy studies of plasma-sprayed materials

1983 ◽  
Vol 41 ◽  
pp. 70-71
Author(s):  
K.R. Subramanian ◽  
A.H. King ◽  
H. Herman
Keyword(s):  
Plasma Spraying ◽  
Substrate Surface ◽  
Flame Temperature ◽  
Ceramic Coatings ◽  
Metallic Substrates ◽  
Hot Plasma ◽  
Almost All ◽  
Plasma Sprayed ◽  
Hostile Environments ◽  
Plasma Spraying Process

Plasma spraying is a technique which is used to apply coatings to metallic substrates for a variety of purposes, including hardfacing, corrosion resistance and thermal barrier applications. Almost all of the applications of this somewhat esoteric fabrication technique involve materials in hostile environments and the integrity of the coatings is of paramount importance: the effects of process variables on such properties as adhesive strength, cohesive strength and hardness of the substrate/coating system, however, are poorly understood.Briefly, the plasma spraying process involves forming a hot plasma jet with a maximum flame temperature of approximately 20,000K and a gas velocity of about 40m/s. Into this jet the coating material is injected, in powder form, so it is heated and projected at the substrate surface. Relatively thick metallic or ceramic coatings may be speedily built up using this technique.

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