2 research outputs found
Genetic polymorphism of the \u3b1s1-casein locus in five populations of goats from Mexico
With the objective of estimating allele frequencies, and testing for
population divergence for the CSN1S1 locus, genotypes of animals from
five goat populations; Saanen (n = 97), Alpine (n = 81) Toggenburg (n =
92), local goats with external appearance similar to the
Murciana-Granadina breed from Central Mexico (n = 26) and heterogeneous
local animals denominated Mosaico Lagunero (n = 30), from Northern
Mexico, were identified using PCR and Xmn1 PCR-RFLP methodology. For
Saanen, Alpine and Toggenburg, the sum of E and F alleles had the
largest frequencies (from 0.468 to 0.789), while for the groups local
Murciana-Granadina and Mosaico Lagunero the sum of the most frequent
allelic groups (A* and B*), were 0.385 and 0.533 respectively. Both
local Murciana-Granadina and Mosaico Lagunero populations showed
heterozygote excess (P < 0.08). The percentage of the total genetic
variation (FST) explained by population differences was 5.16. There was
genetic differentiation for most pair comparisons between populations
(P < 0.05), excepting for Alpine versus Toggenburg, and Toggenburg
versus Mosaico Lagunero (P > 0.05). For Saanen and Alpine the
frequencies of alleles E and F were similar to the same breeds
previously analyzed in Europe. Therefore there are opportunities of
increasing the frequency of the strong alleles for protein content Gene
Assisted Selection (GAS) in these two breeds. For Toggenburg the most
frequent allelic groups were F (0.32) and B* (0.21). Results indicate
differentiation between most populations for this locus. Moreover,
heterozygote excess in local populations indicated breed admixture
Search for ultrarelativistic magnetic monopoles with the Pierre Auger Observatory
We present a search for ultrarelativistic magnetic monopoles with the Pierre Auger observatory. Such
particles, possibly a relic of phase transitions in the early Universe, would deposit a large amount of energy
along their path through the atmosphere, comparable to that of ultrahigh-energy cosmic rays (UHECRs).
The air-shower profile of a magnetic monopole can be effectively distinguished by the fluorescence
detector from that of standard UHECRs. No candidate was found in the data collected between 2004 and
2012, with an expected background of less than 0.1 event from UHECRs. The corresponding
90% confidence level (C.L.) upper limits on the flux of ultrarelativistic magnetic monopoles range from
10^ 1219(cm2 sr s)^ 121 for a Lorentz factor \u3b3 = 10^9 to 2.5
7 10 1221(cm2 sr s)^ 121 for \u3b3 = 10^12. These results\u2014the
first obtained with a UHECR detector\u2014improve previously published limits by up to an order of
magnitude