4,072 research outputs found
Isospin symmetry breaking and the neutron-proton mass difference
QCD sum rules using polynomial kernels are used to evaluate the strong part
of the proton-neutron mass difference DeltaM_np in a model independent fashion.
The result for the mass difference turns out to depend sensitively on the value
of the four quark condensate and reproduces the experimental value of
DeltaM_np for ~ 2^2.Comment: Arguments detailed. Two references added. Version to appear in
Physical Review C. DOI:10.1103/PhysRevC.00.00520
The dynamics of alternative pathways to compensatory substitution
The role of epistatic interactions among loci is a central question in
evolutionary biology and is increasingly relevant in the genomic age. While the
population genetics of compensatory substitution have received considerable
attention, most studies have focused on the case when natural selection is very
strong against deleterious intermediates. In the biologically-plausible
scenario of weak to moderate selection there exist two alternate pathways for
compensatory substitution. In one pathway, a deleterious mutation becomes fixed
prior to occurrence of the compensatory mutation. In the other, the two loci
are simultaneously polymorphic. The rates of compensatory substitution along
these two pathways and their relative probabilities are functions of the
population size, selection strength, mutation rate, and recombination rate. In
this paper these rates and path probabilities are derived analytically and
verified using population genetic simulations. The expected time durations of
these two paths are similar when selection is moderate, but not when selection
is weak. The effect of recombination on the dynamics of the substitution
process are explored using simulation. Using the derived rates, a phylogenetic
substitution model of the compensatory evolution process is presented that
could be used for inference of population genetic parameters from interspecific
data.Comment: 17 pages, 9 figures, 1 table. Accepted to RECOMB Comparative Genomics
Meeting 2013, to be published in BMC Bioinformatic
Isovector Meson Masses from QCD Sum Rules
We present a calculation of the masses of the isovector mesons ( vector,
scalar and pseudoscalar including the established recurrences) using a new
method of finite energy QCD sum rules. The method is based on the idea of
choosing a suitable integration kernel which minimizes the occurring integral
over the cut in the complex energy (squared) plane. We obtain remarkably stable
results in a wide range R, where R is the radius of the integration contour.
The sum rule predictions agree with the experimental values within the expected
accuracy showing that QCD describes single resonances.Comment: Typos and misprints correcte
THE APPLICATION OF BEHAVIORISTIC THEORY IN THE 2013 CURRICULUM LEARNING TO SHAPE THE PRINCIPLES OF STUDENTS' CHARACTERS
The purpose of this study is to describe the application of behavioristic theory in the learning of morality in the 2013 curriculum at the elementary school level. In addition, to reveal the implications of behavioristic theory in learning morality in the 2013 curriculum to shape the morals of elementary school students. This type of research is classified as library research with an interpretative text approach. Data were collected by quoting, adapting, and analyzing using data analysis techniques using the Miles and Huberman model of representative literature and having relevance to the problem discussed, then interpreting the data so that it becomes a conclusion that is considered to answer the problem formulation. The results of the study indicate that there are two main implications, namely: educators utilize preliminary and closing activities of learning as a means to shape the morals of students, and educators cooperate with various components of education staff in schools to form attitudes that lead to moral formation, including: a. ) condition students in an environment that allows the formation of morals, b) create programs that allow students to learn to implement concept learning into practice, c) provide examples to students in the school environment; and d) make a moral commitment to students.The purpose of this study is to describe the application of behavioristic theory in the learning of morality in the 2013 curriculum at the elementary school level. In addition, to reveal the implications of behavioristic theory in learning morality in the 2013 curriculum to shape the morals of elementary school students. This type of research is classified as library research with an interpretative text approach. Data were collected by quoting, adapting, and analyzing using data analysis techniques using the Miles and Huberman model of representative literature and having relevance to the problem discussed, then interpreting the data so that it becomes a conclusion that is considered to answer the problem formulation. The results of the study indicate that there are two main implications, namely: educators utilize preliminary and closing activities of learning as a means to shape the morals of students, and educators cooperate with various components of education staff in schools to form attitudes that lead to moral formation, including: a. ) condition students in an environment that allows the formation of morals, b) create programs that allow students to learn to implement concept learning into practice, c) provide examples to students in the school environment; and d) make a moral commitment to students
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