7,353 research outputs found
Adiabatic Heavy Ion Fusion Potentials for Fusion at Deep Sub-barrier Energies
The fusion cross sections from well above barrier to extreme sub-barrier
energies have been analysed using the energy (E) and angular momentum (L)
dependent barrier penetration model ({\small{ELDBPM}}). From this analysis, the
adiabatic limits of fusion barriers have been determined for a wide range of
heavy ion systems. The empirical prescription of Wilzynska and Wilzynski has
been used with modified radius parameter and surface tension coefficient values
consistent with the parameterization of the nuclear masses. The adiabatic
fusion barriers calculated from this prescription are in good agreement with
the adiabatic barriers deduced from {\small{ELDBPM}} fits to fusion data. The
nuclear potential diffuseness is larger at adiabatic limit, resulting in a
lower leading to increase of "logarithmic slope" observed at
energies well below the barrier. The effective fusion barrier radius and
curvature values are anomalously smaller than the predictions of known
empirical prescriptions. A detailed comparison of the systematics of fusion
barrier with and without L-dependence has been presented.Comment: Revtex file of 6 pages and 3 eps figure
Gossip Codes for Fingerprinting: Construction, Erasure Analysis and Pirate Tracing
This work presents two new construction techniques for q-ary Gossip codes
from tdesigns and Traceability schemes. These Gossip codes achieve the shortest
code length specified in terms of code parameters and can withstand erasures in
digital fingerprinting applications. This work presents the construction of
embedded Gossip codes for extending an existing Gossip code into a bigger code.
It discusses the construction of concatenated codes and realisation of erasure
model through concatenated codes.Comment: 28 page
Molecular Biology and Pathogenesis of Retroviruses
Retroviruses consist of a varied family of enveloped RNA viruses with positive-sense RNAs that replicate in a host cell through the process of reverse transcription. Retroviruses belong to the Retroviridae family that typically carries their genetic material in the form of ribonucleic acid, while the genetic material of their hosts is in the form of deoxyribonucleic acid. Infections with a number of retroviruses can lead to serious conditions, such as AIDS, a range of malignancies, neurological diseases, and added clinical conditions. In addition, some can even become integrated as DNA in the germ line and passed as endogenous viruses from generation to generation. Surprisingly, retroviruses do not appear to straightforwardly activate host innate defenses. On the other hand, attention in these viruses extends beyond their disease causing capabilities. For example, studies on the retroviruses led to the discovery of oncogenes, understanding of mechanisms that regulate eukaryotic gene expression, and these are proving to be valuable research tools in molecular biology and have been used successfully in gene therapy. The central goals of retrovirology today are the treatment and the prevention of human and non-human diseases and to use this virus in research
Arresting Soil Erosion in Hilly Terrains with Pigeonpea - The Chinese Experience
Conservation of the nutrient-rich top soil is extremely important for sustaining agricultural productivity. It is now becoming a serious crop production constraint, particularly in the slopping hilly terrains. The ecology of such areas is rapidly deteriorating and their recovery seems extremely difficult. In southern China, where soil erosion is a serious issue, various plant species were unsuccessfully tried in the past to arrest the soil erosion. The Chinese scientists, in collaboration with ICRISAT, used late maturing pigeonpea cultivars to protect the fragile lands in Guangxi and Yunnan provinces. The planted area under pigeonpea in this system rapidly increased to 700 ha by 2001. This paper summarizes the methodologies used in soil conservation practices involving pigeonpea
Novel Circuit for the Rapid Measurement of Dielectric Constant with Ultra Precision over a Wide Range of Frequencies
A simplified instrument is designed for dielectric constant measurement of liquids and gases over a wide range of frequencies by using 6j5 as variable oscillator and 6E5 electron-ray tube for mechanical resonance indication with the quartz crystal of various frequencies. Measurements with the proposed new circuit are simple, rapid and accurate
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