Effet maternel et effet de la vigueur hybride sur la viabilité de la drosophile (Drosophila melanogaster) aux différents stades du développement pré-imaginal

1983 ◽  
Vol 61 (5) ◽  
pp. 1152-1155 ◽  
Author(s):  
Nicole Cadieu

When larval competition in Drosophila melanogaster is prevented, survival up to imaginal emergence in two inbred strains and their reciprocal hybrids seems to depend on (i) a maternal influence (possibly due to cytoplasmic factors), (ii) the state of inbreeding or outbreeding of the progeny. The study of the death rate during development demonstrates that the maternal effect can be detected at every stage of the preimaginal life (embryo, larva, and pupa). On the other hand heterosis is superimposed on the maternal effect mainly during larval life, the viability for the hybrid larvae being higher than the average of the two parental strains.

1976 ◽  
Vol 18 (4) ◽  
pp. 773-781 ◽  
Author(s):  
Patricia Romans ◽  
R. B. Hodgetts ◽  
D. Nash

A new locus, mel(l)R1, with a maternal effect on embryonic development, has been mapped at about 0.5 on the X chromosome of Drosophila melanogaster and localized cytologically between bands 2D6 and 3A1. Genotypically mutant embryos die if produced by homozygous mutant females but survive if produced by heterozygous females. Two mutant alleles have been isolated. One of these is genetically rescuable: when homozygous mutant females are mated to mutant males, all the embryos die, but when these females are mated to normal males, female offspring are produced. The other allele is not rescuable. Genetic rescue is dominant at this locus since females heterozygous for the two mutant alleles produce female offspring in crosses to normal males.


Genetics ◽  
1986 ◽  
Vol 113 (3) ◽  
pp. 695-712
Author(s):  
Norbert Perrimon ◽  
Dawson Mohler ◽  
Lee Engstrom ◽  
A P Mahowald

ABSTRACT We have examined the number of X-linked loci specifically required only during oogenesis. Complementation analyses among female-sterile (fs) mutations obtained in two mutagenesis screens—Gans' and Mohler's—indicate that any fs locus represented by two or more mutant alleles in Gans' collection are usually present in Mohler's collection. However, when a locus is represented by a single allele in one collection, it is generally not present in the other collection. We propose that this discrepancy is due to the fact that most "fs loci" represented by less than two mutant alleles are, in fact, vital (zygotic lethal) genes, and that the fs alleles are hypomorphic mutations of such genes. In support of this hypothesis we have identified lethal alleles at 12 of these "fs loci." The present analysis has possibly identified all maternal-effect lethal loci detectable by mutations on the X chromosome and has allowed us to reevaluate the number of "ovary-specific fs" loci in the Drosophila genome. Finally, germline clone analysis of a large number of fs mutations was performed in order to estimate the relative contribution of germline and somatic cell derivatives to oogenesis and to embryonic development. All the maternal-effect lethal loci tested are germline-dependent.


1958 ◽  
Vol 36 (6) ◽  
pp. 969-983 ◽  
Author(s):  
L. Butler

Crosses were made between the two inbred lines, C57BL and BALB, and the effects of maternity and genotype on litter size, survival, 30- and 60-day weights, and their variances were assessed. The maternal effect of BALB reduced litter size by.78 to 1.91 when compared with reciprocal crosses of identical genotype. No maternal effect was found for C57; neither did the genotype of the young have any effect on the litter size borne by mothers of this strain. There was a significant increase (2.26 ±.67) in litter size when BALB females produced hybrid instead of inbred young. This was not the result of hybrid males being more prolific, because BALB males mated to non-BALB females produced the largest litters in this experiment. The cross F1 × F1 produced the largest mean litter size. A change in ration affected the litter size when BALB was the mother, but not when C57 was the mother. Fox chow plus linseed produced more young than any of the other three diets.There were no significant differences in the weights of males of any of the generations at 30 days, but the F1 females borne in C57 mothers were larger than the females of other generations, and it appears that the C57 female exerts a maternal effect which causes the female young to mature earlier. The data indicate that the mother exerts the greatest influence on 30-day weights, the genotype of the young having little or no effect. The F1 female has the greatest maternal effect: she increases the 30-day weight by 10–20%.At 60 days the F1 mouse was 15% larger than the corresponding inbred borne in the same female. The mean weights of the F1 and F2 were the same, but the backcrosses were 10% lighter.The variance at 30 days was larger than the corresponding variance at 60 days, and 90% of the variance was in the between-litters component. At 30 days the largest variances were found in the P1, F1, and B.C. generations, while the smallest was found in the F2 indicating that much of the variability was the result of the maternal environment. At 60 days the variances for all generations were essentially the same.MacArthur's large and small strains, which had been produced by 30 generations of selection with only moderate inbreeding, were carried through 20 generations of brother × sister mating. This inbreeding brought about a decrease in the weight of the large line, and an increase in the weights of the small strain. The former may be attributed to the loss of the heterozygotic effect on size, while the latter may be the result of natural counterselection; the smallest mice had few or no young.


2016 ◽  
Vol 6 (2) ◽  
pp. 118-135
Author(s):  
Lucia Della Torre

Not very long ago, scholars saw it fit to name a new and quite widespread phenomenon they had observed developing over the years as the “judicialization” of politics, meaning by it the expanding control of the judiciary at the expenses of the other powers of the State. Things seem yet to have begun to change, especially in Migration Law. Generally quite a marginal branch of the State's corpus iuris, this latter has already lent itself to different forms of experimentations which then, spilling over into other legislative disciplines, end up by becoming the new general rule. The new interaction between the judiciary and the executive in this specific field as it is unfolding in such countries as the UK and Switzerland may prove to be yet another example of these dynamics.


2019 ◽  
Vol 34 (2) ◽  
Author(s):  
Sipho Stephen Nkosi

The note is about the appeal lodged by the late Mrs Winnie Madikizela-Mandela to the SCA against the decision of the Eastern Cape High Court, Mthatha, dismissing her application for review in 2014. In that application, she sought to have reviewed the decision of the Minister of Land Affairs, to transfer the now extended and renovated Qunu property to Mr Mandela and to register it in his name. Because her application was out of time, she also applied for condonation of her delay in making the application. The court a quo dismissed both applications with costs, holding that there had been an undue delay on her part. Mrs Mandela then approached the Supreme Court of Appeal, for special leave to appeal the decision of the court a quo. Two questions fell for decision by the SCA: whether there was an unreasonable and undue delay on Mrs Mandela’s part in instituting review proceedings; and whether the order for costs was appropriate in the circumstances of the case. The SCA held that there was indeed an unreasonable delay (of seventeen years). Shongwe AP (with Swain, Mathopo JJA, Mokgothloa and Rodgers AJJA concurring) held that the fact that there had been an undue delay does not necessarily mean that an order for costs should, of necessity, particularly where, as in this case, the other litigant is the state. It is the writer’s view that two other ancillary points needed to be raised by counsel and pronounced on by the Court: (a) the lawfulness and regularity of the transfer of the Qunu property to Mr Mandela; and (b) Mrs Mandela’s status as a customary-law widow—in relation to Mr Mandela.


2017 ◽  
Vol 1 (1) ◽  
pp. 90
Author(s):  
Dian Septiandani ◽  
Abd. Shomad

Zakat is one of principal worship requiring every individual (<em>mukallaf</em>) with considerable property to spend some of the wealth for zakat under several conditions applied within. On the other hand, tax is an obligation assigned to taxpayers and should be deposited into the state based on policies applied, with no direct return as reward, for financing the national general expense. In their development, both zakat and tax had quite attention from Islamic economic thought. Nevertheless, we, at first, wanted to identify the principles of zakat and tax at the time of Rasulullah SAW. Therefore, this study referred to normative research. The primary data was collected through library/document research and the secondary one was collected through literature review by inventorying and collecting textbooks and other documents related to the studied issue.


Author(s):  
Anatolii Petrovich Mykolaiets

It is noted that from the standpoint of sociology, “management — a function of organized systems of various nature — (technical, biological, social), which ensures the preservation of their structure, maintaining a certain state or transfer to another state, in accordance with the objective laws of the existence of this system, which implemented by a program or deliberately set aside”. Management is carried out through the influence of one subsystem-controlling, on the other-controlled, on the processes taking place in it with the help of information signals or administrative actions. It is proved that self-government allows all members of society or a separate association to fully express their will and interests, overcome alienation, effectively combat bureaucracy, and promote public self-realization of the individual. At the same time, wide direct participation in the management of insufficiently competent participants who are not responsible for their decisions, contradicts the social division of labor, reduces the effectiveness of management, complicates the rationalization of production. This can lead to the dominance of short-term interests over promising interests. Therefore, it is always important for society to find the optimal measure of a combination of self-management and professional management. It is determined that social representation acts, on the one hand, as the most important intermediary between the state and the population, the protection of social interests in a politically heterogeneous environment. On the other hand, it ensures the operation of a mechanism for correcting the political system, which makes it possible to correct previously adopted decisions in a legitimate way, without resorting to violence. It is proved that the system of social representation influences the most important political relations, promotes social integration, that is, the inclusion of various social groups and public associations in the political system. It is proposed to use the term “self-government” in relation to several levels of people’s association: the whole community — public self-government or self-government of the people, to individual regions or communities — local, to production management — production self-government. Traditionally, self-government is seen as an alternative to public administration. Ideology and practice of selfgovernment originate from the primitive, communal-tribal democracy. It is established that, in practice, centralization has become a “natural form of government”. In its pure form, centralization does not recognize the autonomy of places and even local life. It is characteristic of authoritarian regimes, but it is also widely used by democratic regimes, where they believe that political freedoms should be fixed only at the national level. It is determined that since the state has achieved certain sizes, it is impossible to abandon the admission of the existence of local authorities. Thus, deconcentration appears as one of the forms of centralization and as a cure for the excesses of the latter. Deconcentration assumes the presence of local bodies, which depend on the government functionally and in the order of subordination of their officials. The dependency of officials means that the leadership of local authorities is appointed by the central government and may be displaced.


2016 ◽  
Vol 1 (1) ◽  
Author(s):  
D.G. Shah ◽  
D.N. Mehta ◽  
R.V. Gujar

Bryophytes are the second largest group of land plants and are also known as the amphibians of the plant kingdom. 67 species of bryophytes have been reported from select locations across the state of Gujrat. The status of family fissidentaceae which is a large moss family is being presented in this paper. Globally the family consists of 10 genera but only one genus, Fissidens Hedw. has been collected from Gujarat. Fissidens is characterized by a unique leaf structure and shows the presence of three distinct lamina, the dorsal, the ventral and the vaginant lamina. A total of 8 species of Fissidens have been reported from the state based on vegetative characters as no sporophyte stages were collected earlier. Species reported from the neighboring states also showed the absence of sporophytes. The identification of different species was difficult due to substantial overlap in vegetative characters. Hence a detailed study on the diversity of members of Fissidentaceae in Gujarat was carried out between November 2013 and February 2015. In present study 8 distinct species of Fissidens have been collected from different parts of the state. Three species Fissidens splachnobryoides Broth., Fissidens zollingerii Mont. and Fissidens curvato-involutus Dixon. have been identified while the other five are still to be identified. Fissidens zollingerii Mont. and Fissidens xiphoides M. Fleisch., which have been reported as distinct species are actually synonyms according to TROPICOS database. The presence of sexual reproductive structures and sporophytes for several Fissidens species are also being reported for the first time from the state.


2015 ◽  
Vol 4 (3) ◽  
Author(s):  
Vinay Chauhan ◽  
Sushma Kaushal

Environmental scanning yields greater anticipatory management that provides important inputs for aquitision and use of information for planning and designing organization strategies. Apart from this, effective environmental scanning activities are likely to deal with threats and grasp the opportunities to finally link with enhancing organizational effectiveness. In fact this relationship matrix has led the researchers to conduct an environmental scanning through an examination of the existing status the components of the macro-environment vis-a-vis their relationship with the organizational effectiveness. There are a number of approaches, which describe the macro-environment, of which PEST analysis is regarded as the most common approach for considering the external business environment. Thus, the present study applies PEST analysis to scan the existing business environment. Jammu and Kashmir due to its peculiar political, geographical, economic, and socio-cultural features, had led its cost mountain economy become a distinctive identity. Despite the fact that the state has rich endowments, international relations with its neighbours vis-a-vis its impact on political environment also pose developmental challenges for the business units operating in the state. This has provided valid rationale for conducting the present. The environmental scanning is done through the perception of the select entrepreneurs operating MSMEs in the state of J & K. An impact analysis of environmental factors (PEST) on the organizational effectiveness is also done in the study. The findings of the study show that the political environment of the state that is not favourable for entrepreneural development whereas the rest of the other drivers of PEST i.e. economic environment, socio-cultural environment, and technological environment show a favourable response of the entrepreneurs. In terms of cause and effect relationship, it is found that the first two drivers of the PEST i.e. political and economic dimension impacts OE positively whereas the other two dimensions namely socio-cultural and technological impacts OE negatively but it is pertinent to mention that the impact is very less and is insigninificant. The study also suggests some of strategic options for developing and creating an enabling environment for successful entrepreneurial development to achieve integrated development of the state.


Author(s):  
Clive Holes

The vocabulary of the modern Gulf Arabic dialects contains many items of ancient Mesopotamian origin; there is also evidence of early south Arabian influences. Historically, three dialect types existed in the region: Najdi, coastal (these two are ‘A dialects’), and Baḥārna (‘B’ dialects). There must long have been contact between these three, but the main interface was between the Najdi and the coastal type. The (Shīˁī) Baḥārna lived in separate settlements, pursued livelihoods specific to them, and did not marry with the other two groups. All of this preserved their dialect. This sociolinguistic division was most evident in the state of Bahrain. In recent decades, changes in employment and increased urbanization have brought about increased interdialectal contact, resulting in the loss of B dialect features and a homogenization of the A dialects to the point that one can now speak of the emergence of a Gulf koine.


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