scholarly journals Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies

1998 ◽  
Vol 128 (2) ◽  
pp. 299-308 ◽  
Author(s):  
Ph. Prugniel ◽  
Ph. Héraudeau
2003 ◽  
Vol 77 (3) ◽  
pp. 2081-2092 ◽  
Author(s):  
M. M. Addo ◽  
X. G. Yu ◽  
A. Rathod ◽  
D. Cohen ◽  
R. L. Eldridge ◽  
...  

ABSTRACT Cellular immune responses play a critical role in the control of human immunodeficiency virus type 1 (HIV-1); however, the breadth of these responses at the single-epitope level has not been comprehensively assessed. We therefore screened peripheral blood mononuclear cells (PBMC) from 57 individuals at different stages of HIV-1 infection for virus-specific T-cell responses using a matrix of 504 overlapping peptides spanning all expressed HIV-1 proteins in a gamma interferon-enzyme-linked immunospot (Elispot) assay. HIV-1-specific T-cell responses were detectable in all study subjects, with a median of 14 individual epitopic regions targeted per person (range, 2 to 42), and all 14 HIV-1 protein subunits were recognized. HIV-1 p24-Gag and Nef contained the highest epitope density and were also the most frequently recognized HIV-1 proteins. The total magnitude of the HIV-1-specific response ranged from 280 to 25,860 spot-forming cells (SFC)/106 PBMC (median, 4,245) among all study participants. However, the number of epitopic regions targeted, the protein subunits recognized, and the total magnitude of HIV-1-specific responses varied significantly among the tested individuals, with the strongest and broadest responses detectable in individuals with untreated chronic HIV-1 infection. Neither the breadth nor the magnitude of the total HIV-1-specific CD8+-T-cell responses correlated with plasma viral load. We conclude that a peptide matrix-based Elispot assay allows for rapid, sensitive, specific, and efficient assessment of cellular immune responses directed against the entire expressed HIV-1 genome. These data also suggest that the impact of T-cell responses on control of viral replication cannot be explained by the mere quantification of the magnitude and breadth of the CD8+-T-cell response, even if a comprehensive pan-genome screening approach is applied.


2012 ◽  
Vol 10 (H16) ◽  
pp. 140-140
Author(s):  
Julio Angel Fernández

AbstractWe analyze the flux of new and evolved long-period comets (LPCs) reaching the Earth's neighborhood (perihelion distances q < 1.3 AU), their physical lifetimes, and their implications as regards to the amount of meteoritic matter that is being deposited in the near-Earth region. The flux of LPCs with q < 1.3 au is found to be of about 340 ± 40, brighter than absolute total magnitude 8.6 (radius R ~ 0.6 km) (Fernández and Sosa 2012). Bearing in mind that most of these comets disintegrate into meteoritic matter, this represents a large contribution to the interplanetary dust complex which requires an amount of matter of about 10 tons s−1 to keep it in steady state. These aspects, as well as the impact rate with Earth of meteoroids of LPC origin, will be discussed in this presentation.


1999 ◽  
Vol 171 ◽  
pp. 154-156
Author(s):  
T. Bremnes ◽  
B. Binggeli ◽  
P. Prugniel

AbstractWe present preliminary results from two observing campaigns where global photometric data for most dwarf galaxies in the M81 and M101 groups as well as some field dwarfs were obtained. The galaxies in the denser M81 group are more often of dwarf elliptical type and are redder and fainter than those of the M101 group and surrounding field, which are mostly of the dwarf irregular types. But both types follow the same total magnitude - central surface brightness relation, so there might be an evolutionary connection between the two classes.


2004 ◽  
Vol 78 (9) ◽  
pp. 4463-4477 ◽  
Author(s):  
Daniel E. Kaufmann ◽  
Paul M. Bailey ◽  
John Sidney ◽  
Bradford Wagner ◽  
Philip J. Norris ◽  
...  

ABSTRACT Increasing evidence suggests that human immunodeficiency virus type 1 (HIV-1)-specific CD4 T-cell responses contribute to effective immune control of HIV-1 infection. However, the breadths and specificities of these responses have not been defined. We screened fresh CD8-depleted peripheral blood mononuclear cells (PBMC) from 36 subjects at different stages of HIV-1 infection for virus-specific CD4 responses by gamma interferon enzyme-linked immunospot assay, using 410 overlapping peptides spanning all HIV-1 proteins (based on the clade B consensus sequence). HIV-1-specific CD4 responses were identified in 30 of the 36 individuals studied, with the strongest and broadest responses detected in persons treated in acute infection who underwent treatment interruption. In individuals with identified responses, the total number of recognized HIV-1 peptides ranged from 1 to 36 (median, 7) and the total magnitude of responses ranged from 80 to >14,600 (median, 990) spot-forming cells/106 CD8-depleted PBMC. Neither the total magnitude nor the number of responses correlated with viremia. The most frequent and robust responses were directed against epitopes within the Gag and Nef proteins. Peptides targeted by ≥25% of individuals were then tested for binding to a panel of common HLA-DR molecules. All bound broadly to at least four of the eight alleles tested, and two bound to all of the HLA-DR molecules studied. Fine mapping and HLA restriction of the responses against four of these peptides showed a combination of clustering of epitopes and promiscuous presentation of the same epitopes by different HLA class II alleles. These findings have implications for the design of immunotherapeutic strategies and for testing candidate HIV vaccines.


1976 ◽  
Vol 8 (4) ◽  
pp. 309-333 ◽  
Author(s):  
K. F Dyer

SummaryA review of the pattern and magnitude of nero–white mating in the US is presented from the time of the earliest arrival of negroes in the American colonies until the present, using historical, demographic, census and genetic evidence.The relative magnitude of negro male–white female matings compared to the converse are analysed in view of the different genetic outcomes of these two types of mating for X-linked genes. Contrary to many strongly stated opinions it is conclued from the historical evidence that, even from the earliest days of slavery, negro male–white female matings were a significant proportion of all negro–white matings. Census and demographic evidence suggests that their frequency increased so that from the time of the Civil War on they have formed a majority of inter-racial matings.Genetic evidence based on estimates of the amout of admixture of white genes in a number of negro populations is considered. Estimates of admixture for the X-linked genes G6PD, and those for colour blindness are as high or higher than those derived from comparable autosomal genes.Some observations on the total magnitude of negro–white mating, on the phenomenon of passing and on the relative socio-economic status of those involved are also made.The implication of the findings on these phenomena for investigations and hypotheses concerning differences in intelligence and intellectual abilites between the races, particulary spatial ability which is thought to be strongly influenced by a gene on the X chromosome, are considered.It is concluded that some of the assumptions made in proposing hypotheses regarding the origin and distribution of these abilities in the American negro are at variance with genetic, historical and sociological findings.


2018 ◽  
Vol 56 ◽  
pp. 01003
Author(s):  
Victor Sinitsyn ◽  
Pavel Menshikov ◽  
Vyacheslav Kutuev

The article deals with the question of the effect of explosive characteristics of emulsion explosives on the shotpile width. Currently, there are two main points of view to select an efficient type of explosive, which contributes to the qualitative destruction (fragmentation) of coarse clastic rocks. The first is based on the assumption that the detonation velocity of explosives must correspond to the break-down point of the rock (dynamic compression). Another point of view is that the detonation pressure of explosives determines only the head part of the pulse, on which the rock fragmentation is dependent only near the charge, in the contact zone around the borehole. The fragmentation of the entire rock volume within a given borehole array depends on the total magnitude of the explosion pulse, determined not by the detonation velocity, but by the total energy reserve of the explosive charge. Experimental explosions with some of the most common industrial explosives have been carried out in the current conditions of blasting of borehole charges by various types of industrial explosives from the point of view to select the most important parameter, which determines its influence on the shotpile width The investigations have been carried out according to the data obtained to establish that the energy properties of explosives (heat of explosive transformation and density of explosives) determine the decisive influence on the shotpile width, and the operability, the volume of the released gases, the detonation velocity for the change in the shotpile width have very little effect and may not be taken into account in calculations for the prediction of the shotpile.


1994 ◽  
Vol 161 ◽  
pp. 37-41
Author(s):  
C. Pollas

The name of Zwicky is attached to the first photographic Palomar Survey and to the History of SNe study. An exciting study resumed by the striking image (M = −19) of a transient source appearing at extragalactic distance, as bright as the total magnitude of its parent galaxy. Expected to explode once a century, such an event is rare. But the more galaxies are checked the more SNe are found. That is why the wide-field is a good tool. The Palomar team SNe activity was followed by a quiet period of the whole SNe discovery (Fig. 1); from those the Cero El Robles search emerged in the early eighties. Several important patrols continued with Schmidt telescopes of size about 0.5 m (Bern, Hungary, Urss…) in spite of the low level of SNe found. Important because knowing that no SN exploded in a galaxy (especially in the sample of nearby galaxies) is the basis of the statistics. The SNe production increased in the late eighties. At the same time, the closest modern SN (1987A) led for the first time to the use of a number of instruments complementing each other to increase our understanding of SNe. But more important than the production of new SNe, is the increase of their spectroscopic classification which is necessary to the SNe work.


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