The recessive N gene in New Zealand Romney sheep

1955 ◽  
Vol 6 (6) ◽  
pp. 833 ◽  
Author(s):  
FW Dry

The recessive N gene, nr, is demonstrated by monogenic ratios. For the most part nr/nr characters are intermediate between those of N/N and N/+. About a sixth of nr/nr lambs have no shoulder patch, and in certain fibre type details, and in hairiness, nr/nr animals tend to be intermediate between the two dominant-N genotypes. On the other hand, all nr/nr ewes have been hornless; a few have had horn-lumps, one scum By contrast, about one N/+ ewe in 10 grows horns. All the nr/nr rams reared to 1 year, except one with scurs, have grown horns. Carrier (+/nr) sheep have birthcoats which we do not know how to distinguish from those of ordinary Romneys, though there is evidence that one dose of nr increases halo-abundance on the back slightly. A few +/nr lambs have been grade VI. Just a few +/nr sheep have fleeces as hairy as the average N/+. A quarter or more of the +/nr rams have had horns, mostly small, at 4 months, and nearly all the others have had scurs. The genes N and nr are not allelic, but may be linked. Because the sheep has 26 pairs of autosomes free assortment seems more probable. In general the characterization of sheep deemed N/+.+/nr is intermediate between that of N/N.+/+ and N/+.+/+. The noticeable difference between N/+.+/nr and +/+ nr/nr is the more powerful growth of horns in the double heterozygotes. An analysis of breeding results from N/+.+/nr sheep indicates that the great majority of N/+.nr/nr animals of both sexes have the horn and halocoverage characters of homozygous dominant-N's. In N/+.+/nr, some ewes have horns, and the shoulder patch is absent about as often as in nr/nr. The frequencies of these characters in N/+.+/nr are applied in showing that the genetic basis of horns in ewes, and the genetic basis of full halo-coverage, in heterozygotes of the dominant-N stock are different; and that it is not the gene nr which makes horns grow in the dominant-N heterozygous ewes; and one piece of evidence suggests that it is not the nr gene that determines absence of shoulder patch in the birthcoats of the dominant-N stock. It is concluded that if the dominant-N stock is not completely free from nr, that gene has only the same sort of frequency as in the Romney breed. Matings made as +/+.nr/nr X +/+.+/+, the latter no-halo ewes, from flocks outside the College, or if bred at the College unrelated to any N-type sheep, have given a small proportion of N-grade lambs. It now appears that at least most of these lambs, called 'dominoes', have received one dose of a dominant gene for N-grade, probably the gene N, from the no-halo parent. One no-halo ewe from an outside source had an N-grade son, proved nr/nr, by a domino ram, the dam thus being shown to carry the gene nr.

1955 ◽  
Vol 6 (5) ◽  
pp. 725 ◽  
Author(s):  
FW Dry

The existence of the dominant N gene, derived from two different sources, has been established by monogenic ratios. The gene is variable in expression in the heterozygote, and is pleiotropic. Horns are a sex-influenced expression of this gene, being dominant in males and recessive in females, with exceptions of the order of one in 10 in both sexes. There are hints that the exceptions in rams have a genetic basis, and strong evidence that this is so in heterozygous ewes, a dominant gene, F, variable in expression, being postulated. In the birthcoat of heterozygotes the expression of the N gene varies over a range as wide as is possible. There is extreme variation in halo-coverage over the body in animals of N-abundance on the back, and all halo-grades, from borderline-N to no-halo, are found in the one-sixth of heterozygotes less than N-grade. There is evidence that some part in causing the heterozygote to be less than N-grade is played by genes which reduce the abundance of halo-hairs on the main area of the body in non-N lambs. Possibly one dominigene, not linked with N, is powerful in the heterozygote. Heterozygous dominant N-grade lambs, with very few exceptions, can be distinguished from homozygotes in having halo-hair abundance reduced below that of N-grade at the anterior end of the body, at least in a small area behind the shoulder which is called the shoulder patch. The absence of the shoulder patch in heterozygotes has a genetic basis. Very occasionally there appears to be overlap between the two genotypes in the opposite direction. Recently a very small number of lambs thought to be homozygotes have been a little short of full halo-hair abundance on the shoulder patch on either one or both sides of the body. It is also of some help in distinguishing the genotypes that homozygous ram lambs have lumps in the horn positions, while heterozygous ram lambs frequently have no lumps at birth. On the average homozygous fleeces are more coarsely hairy than heterozygous, and contain more secondary kemp. In setting out the facts from which the above circle of conclusions is drawn it is sometimes convenient to make use at an earlier stage of something which is not proved until later. This applies especially to distinguishing homozygote and heterozygote.


1958 ◽  
Vol 9 (3) ◽  
pp. 348 ◽  
Author(s):  
FW Dry

Another NS-grade sheep, a horned ewe from an ordinary Romney flock, is judged on progeny to have been N/+. Further breeding results are consistent with the simple genetic basis of horns in N/+ ewes previously postulated, namely, a fortifier gene F. Additional evidence is given for a genetic basis of the comparative scarcity of halo-hairs on the main area of the body of low-N N/+ lambs. It is a reasonable guess that selection would fairly quickly build up a stock in which the gene N could be called recessive, in that its expression in heterozygotes fell short of VI. In work with low-N sheep two horned rams, twin sons of a low-N ram with very large horns, have proved not to possess N. Horns in these rams clearly have a simple genetic basis. One N-grade ram has been shown to be +/nr, and it is likely that his twin brother, which closely resembled him, was also +/nr. The N-type characterization of these twin rams was feeble in several respects. There is evidence that the nr gene is helped to N-grade expression by multiple factors which are thus dominigenes. This is a third possible way, in addition to picking up N from a low-N or nr from a carrier, in which an nr/nr sheep mated with non-N may have an N-grade lamb. The original hypothesis of a main dominigene remains unproved. Better evidence is given that the nr gene helps horns to grow in N/+ . +/nr ewes. After repeating the back-cross, N/ +. +/nr x + / + .nr/nr, the conclusion is adopted that N and nr are independent, residing on different chromosomes. Results from that back-cross have strengthened the belief that at least the great majority of sheep of both sexes of the high-dosage genotype N/+ .nrlnr have the complete halo-coverage and hornedness of N/N. +/ +


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.


2018 ◽  
Vol 9 (1) ◽  
pp. 31-42
Author(s):  
Rysa Sahrial

Poverty is one continuing social issue which is hard to solve. Dealing with this problem, Islam has already had the alternative solution that is tithe (Zakat). Zakat is implemented to decrease economy imbalanced appeared in the society. While in fact, not all the Moslem pay Zakat. There are five factors as the reason why Moslem didn’t do that. First, some Muzakki wants to deliver his zakat directly.Seconde, not all Muzakki know how much Zakat must be paid. The other factors are Limited information about Mustahik home, limited time that Muzakki have to deliver his Zakat directly and the easiness to report Mustahik data. Dealing with those factors, it is required to have an information system which can make Muzakki meets Mustahik. In this research, information system application used Extreme Programming (XP) development method. XP method is required to program a system which will be made by accomodating the users’ needs and expectations.


Author(s):  
James Meffan

This chapter discusses the history of multicultural and transnational novels in New Zealand. A novel set in New Zealand will have to deal with questions about cultural access rights on the one hand and cultural coverage on the other. The term ‘transnational novel’ gains its relevance from questions about cultural and national identity, questions that have particularly exercised nations formed from colonial history. The chapter considers novels that demonstrate and respond to perceived deficiencies in wider discourses of cultural and national identity by way of comparison between New Zealand and somewhere else. These include Amelia Batistich's Another Mountain, Another Song (1981), Albert Wendt's Sons for the Return Home (1973) and Black Rainbow (1992), James McNeish's Penelope's Island (1990), Stephanie Johnson's The Heart's Wild Surf (2003), and Lloyd Jones's Mister Pip (2006).


Genetics ◽  
2000 ◽  
Vol 154 (1) ◽  
pp. 121-132
Author(s):  
Zhen Hu ◽  
Yingzi Yue ◽  
Hua Jiang ◽  
Bin Zhang ◽  
Peter W Sherwood ◽  
...  

Abstract Expression of the MAL genes required for maltose fermentation in Saccharomyces cerevisiae is induced by maltose and repressed by glucose. Maltose-inducible regulation requires maltose permease and the MAL-activator protein, a DNA-binding transcription factor encoded by MAL63 and its homologues at the other MAL loci. Previously, we showed that the Mig1 repressor mediates glucose repression of MAL gene expression. Glucose also blocks MAL-activator-mediated maltose induction through a Mig1p-independent mechanism that we refer to as glucose inhibition. Here we report the characterization of this process. Our results indicate that glucose inhibition is also Mig2p independent. Moreover, we show that neither overexpression of the MAL-activator nor elimination of inducer exclusion is sufficient to relieve glucose inhibition, suggesting that glucose acts to inhibit induction by affecting maltose sensing and/or signaling. The glucose inhibition pathway requires HXK2, REG1, and GSF1 and appears to overlap upstream with the glucose repression pathway. The likely target of glucose inhibition is Snf1 protein kinase. Evidence is presented indicating that, in addition to its role in the inactivation of Mig1p, Snf1p is required post-transcriptionally for the synthesis of maltose permease whose function is essential for maltose induction.


Mathematics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 116
Author(s):  
Qi Liu ◽  
Yongjin Li

In this paper, we will introduce a new geometric constant LYJ(λ,μ,X) based on an equivalent characterization of inner product space, which was proposed by Moslehian and Rassias. We first discuss some equivalent forms of the proposed constant. Next, a characterization of uniformly non-square is given. Moreover, some sufficient conditions which imply weak normal structure are presented. Finally, we obtain some relationship between the other well-known geometric constants and LYJ(λ,μ,X). Also, this new coefficient is computed for X being concrete space.


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