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Report of Investigations No. 131 Origin and Diagenesis of Cap Rock, Gyp Hill and Oakwood Salt Domes, Texas
UT Librarie
FURTHER STUDIES OF THE STIMULATION OF DNA SYNTHESIS IN CULTURES OF SPLEEN CELL SUSPENSIONS BY HOMOLOGOUS CELLS IN INBRED STRAINS OF MICE AND RATS
The early proliferative response previously demonstrated in rabbits has now been shown to follow the mixing of spleen cell suspensions from 2 inbred strains of mice or rats. The size of the response is comparable to that seen in cells from hyperimmune animals exposed to antigen in vitro. Autoradiographs of cells from stimulated cultures showed 1 to 4 per cent of the total population had incorporated thymidine. Modifications in the conditions necessary for the culture of mice and rat spleen cell suspensions and the measurement of thymidine incorporation are described. No responses were observed in isologous mixes. The responses obtained on mixing individual pairs of spleens from different strains showed relatively little variation. Responses were obtained in all of the 21 possible combinations between 7 inbred strains of mice. Responses were obtained when parental cells were mixed with their F1 hybrids. Analysis of these responses showed that, in every case, parental-F1 hybrid responses were less intense than those between the 2 parents. It was shown that there was no inherent defect in the ability of the hybrid cells to respond when mixed with an unrelated strain. The results suggested that the hybrid cells made no response to the parent cells although this was not conclusively established. This has been taken as circumstantial evidence that the response is immunological in nature. The significance of the vigor of the response and the large fraction of the immunologically competent cells that take part is discussed
SPLEEN CELL PROLIFERATION IN RESPONSE TO HOMOLOGOUS ANTIGENS STUDIED IN CONGENIC RESISTANT STRAINS OF MICE
The proliferative responses obtained when spleen cell suspensions from two different inbred strains of mice were mixed were investigated further using congenic resistant strain pairs. Strong responses were obtained in 9 cases out of 12 where the two strains differed at a single gene locus controlling an H-2 histocompatibility antigen. No responses were obtained where the difference occurred at loci controlling weak histocompatibility antigens. These findings have been taken to provide additional circumstantial evidence that the response represents an in vitro homograft reaction to homologous tissue antigens
Galaxy alignment on large and small scales
Galaxies are not randomly distributed across the universe but showing
different kinds of alignment on different scales. On small scales satellite
galaxies have a tendency to distribute along the major axis of the central
galaxy, with dependence on galaxy properties that both red satellites and
centrals have stronger alignment than their blue counterparts. On large scales,
it is found that the major axes of Luminous Red Galaxies (LRGs) have
correlation up to 30Mpc/h. Using hydro-dynamical simulation with star
formation, we investigate the origin of galaxy alignment on different scales.
It is found that most red satellite galaxies stay in the inner region of dark
matter halo inside which the shape of central galaxy is well aligned with the
dark matter distribution. Red centrals have stronger alignment than blue ones
as they live in massive haloes and the central galaxy-halo alignment increases
with halo mass. On large scales, the alignment of LRGs is also from the
galaxy-halo shape correlation, but with some extent of mis-alignment. The
massive haloes have stronger alignment than haloes in filament which connect
massive haloes. This is contrary to the naive expectation that cosmic filament
is the cause of halo alignment.Comment: 4 pages, 3 figures, To appear in the proceedings of the IAU Symposium
308 "The Zeldovich Universe: Genesis and Growth of the Cosmic Web
Descreening of Field Effect in Electrically Gated Nanopores
This modeling work investigates the electrical modulation characteristics of
field-effect gated nanopores. Highly nonlinear current modulations are observed
in nanopores with non-overlapping electric double layers, including those with
pore diameters 100 times the Debye screening length. We attribute this extended
field-effect gating to a descreening effect, i.e. the counter-ions do not fully
relax to screen the gating potential due to the presence of strong ionic
transport
On the Relation between Solar Activity and Clear-Sky Terrestrial Irradiance
The Mauna Loa Observatory record of direct-beam solar irradiance measurements
for the years 1958-2010 is analysed to investigate the variation of clear-sky
terrestrial insolation with solar activity over more than four solar cycles.
The raw irradiance data exhibit a marked seasonal cycle, extended periods of
lower irradiance due to emissions of volcanic aerosols, and a long-term
decrease in atmospheric transmission independent of solar activity. After
correcting for these effects, it is found that clear-sky terrestrial irradiance
typically varies by about 0.2 +/- 0.1% over the course of the solar cycle, a
change of the same order of magnitude as the variations of the total solar
irradiance above the atmosphere. An investigation of changes in the clear-sky
atmospheric transmission fails to find a significant trend with sunspot number.
Hence there is no evidence for a yet unknown effect amplifying variations of
clear-sky irradiance with solar activity.Comment: 16 pages, 7 figures, in press at Solar Physics; minor changes to the
text to match final published versio
REGULATION OF THE IMMUNE RESPONSE : I. DIFFERENTIAL EFFECT OF PASSIVELY ADMINISTERED ANTIBODY ON THE THYMUS-DERIVED AND BONE MARROW-DERIVED LYMPHOCYTES
The effect of passively transfered antiserum against sheep erythrocytes (SRBC) on the antigen stimulated increase of SRBC-specific plaque-forming cells (anti-SRBC-PFC) and SRBC-specific thymus-derived lymphocytes (SRBC-specific T-cells) in the mouse spleen was examined. A dose of antiserum which severely suppressed the development of anti-SRBC-PFC did not prevent the increase in SRBC-specific T-cells, as measured by their ability to cooperate in the in vitro response to trinitrophenylated (TNP) SRBC. It was shown that the insensitivity of these T-cells to antiserum could not be explained by their low antigen requirement as compared to that of PFC. In the in vivo response of mice to TNP-SRBC, antibody specific for TNP suppressed the appearance of both anti-TNP- and anti-SRBC-PFC. The presence of free SRBC specifically prevented the suppression of the anti-SRBC-PFC. These observations are consistent with opsonization by phagocytic cells as the primary means of the observed suppression of PFC development by antibody
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