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Immunohistochemical Studies of S-100 Protein During Postnatal Ontogenesis of the Brain of Two Strains of Rats
We have studied the dynamics of the appearance of cells reacting positively with anti-S-100 protein antiserum, during postnatal neurocytogenesis in the brain of rats of two strains differing in their susceptibility to sound stimuli. The postnatal time of appearance of cells reacting positively with anti-S-100 protein antiserum was somewhat later in rats susceptible to sound-induced seizures than in sound-resistant rats. These differences concerned mainly the cerebral cortex of 12-day-old rats. By day 21 of postnatal life these differences had disappeared. In subcortical structures of the brain, S-100 protein was first found on the 4th to the 5th day of life and the rate of appearance of cells containing this protein was similar in the two strains
A lower bound on intergalactic magnetic fields from time variability of 1ES 0229+200 from MAGIC and Fermi/LAT observations
Extended and delayed emission around distant TeV sources induced by the
effects of propagation of gamma rays through the intergalactic medium can be
used for the measurement of the intergalactic magnetic field (IGMF). We search
for delayed GeV emission from the hard-spectrum TeV blazar 1ES 0229+200 with
the goal to detect or constrain the IGMF-dependent secondary flux generated
during the propagation of TeV gamma rays through the intergalactic medium. We
analyze the most recent MAGIC observations over a 5 year time span and
complement them with historic data of the H.E.S.S. and VERITAS telescopes along
with a 12-year long exposure of the Fermi/LAT telescope. We use them to trace
source evolution in the GeV-TeV band over one-and-a-half decade in time. We use
Monte Carlo simulations to predict the delayed secondary gamma-ray flux,
modulated by the source variability, as revealed by TeV-band observations. We
then compare these predictions for various assumed IGMF strengths to all
available measurements of the gamma-ray flux evolution. We find that the source
flux in the energy range above 200 GeV experiences variations around its
average on the 14 years time span of observations. No evidence for the flux
variability is found in 1-100 GeV energy range accessible to Fermi/LAT.
Non-detection of variability due to delayed emission from electromagnetic
cascade developing in the intergalactic medium imposes a lower bound of
B>1.8e-17 G for long correlation length IGMF and B>1e-14 G for an IGMF of the
cosmological origin. Though weaker than the one previously derived from the
analysis of Fermi/LAT data, this bound is more robust, being based on a
conservative intrinsic source spectrum estimate and accounting for the details
of source variability in the TeV energy band. We discuss implications of this
bound for cosmological magnetic fields which might explain the baryon asymmetry
of the Universe.Comment: 10 pages, 5 figures, accepted to A&A. Corresponding authors: Ievgen
Vovk, Paolo Da Vela (mailto:[email protected]) and Andrii Neronov
(mailto:[email protected]
Investigation of the gene regulation of the spectrum of lactate dehydrogenase isoenzymes in the mouse liver.
The Influence of Donor Age, Nerve Growth Factor, and Cografting with Drosophila Cells on Survival of Peripherally Grafted Embryonic or Fetal Rat Dorsal Root Ganglia
Genetics of esterases in Drosophila of the virilis group. II. Sequential expression of paternal and maternal esterases in ontogenesis
Generation of mutant mice with targeted disruption of two members of the d4 gene family: neuro-d4 and cer-d4
Comparative study of appearance of water-soluble antigens and brain esterase fractions in ontogenesis of two strains of rats
Analysis of the overexpression of a newly found gene toothrin in Drosophila
A newly found locus of the Drosophila melanogaster genome, named toothrin (tth) has been used to study the role of the conserved the 2/3 domain of genes from the d4 family. In contrast to all vertebrates studied (including humans), in which the 2/3 domain is always accompanied by the d4 domain, the tth gene contains the sequence encoding the 2/3 domain but lacks that encoding the d4 domain. The tth gene overexpression has been studied using the two-component system UAS-GAL4. It has been demonstrated that the tth overexpression at the third-instar larval (prepupal) stage decreases survival rate, simultaneously causing a substantial deceleration of development in Drosophila. It is known that the change of developmental stages in Drosophila is controlled by the rates of the expression of ecdysteroid and juvenile hormones (JHs). It is supposed that the overexpression of the tth gene causes either a shift in the ecdysterone-to-JH ratio (through a decreased JH decay rate or a delayed initiation of ecdysone synthesis) or a deceleration of the release of ecdysterones synthesized