1,699 research outputs found
Transport coefficients of heavy baryons
We compute the transport coefficients (drag and momentum diffusion) of the
low-lying heavy baryons and in a medium of light mesons
formed at the later stages of high-energy heavy-ion collisions. We employ the
Fokker-Planck approach to obtain the transport coefficients from unitarized
baryon-meson interactions based on effective field theories that respect chiral
and heavy-quark symmetries. We provide the transport coefficients as a function
of temperature and heavy-baryon momentum, and analyze the applicability of
certain nonrelativistic estimates. Moreover we compare our outcome for the
spatial diffusion coefficient to the one coming from the solution of the
Boltzmann-Uehling-Uhlenbeck transport equation and we find a very good
agreement between both calculations. The transport coefficients for
and in a thermal bath will be used in a subsequent publication as
input in a Langevin evolution code for the generation and propagation of heavy
particles in heavy-ion collisions at LHC and RHIC energies.Comment: 26 pages, 12 figures. Title changed. Small additions and corrections.
Version accepted for publication by Physical Review D journa
Validation of Potential Fishing Zone advisories in Minicoy region of Lakshadweep with special reference to skipjack tuna
Itensive validation programme of Potential Fishing Zone (PFZ) advisories carried
ut by the Central Marine Fisheries Research Institute around Minicoy island reealed
positive relationship between PFZ and occurrence/abundance of skipjack
ma (Katsuwonus pelamis). The usefulness of PFZ advisories for the tuna pole and
ne fishing fleet around Minicoy island especially for reducing the searching time
3r tuna shoals and thereby effecting an overall reduction in the cost of fishing oprations
is highlighted
Application of remote sensing techniques for locating pelagic fish concentrations along the Kerala Coast (SW Coast of India) and Minicoy waters
Intensive validation programme on Potential Fishing Zone (PPZ) forecasts carried out by the MARSIS Centre of Central Marine Fisheries Research Institute, Cochin, at 17 selected fish landing centres along the Kerala coast and around Minicoy Island between November 1995 and May 1997 revealed positive relationship between PPZ and occurrence / abundance of commercially important pelagic tlshes, An
attempt is made to identify possible reasons for the above, based on results of oceanographic investigations undertaken in the area and also taking into consideration their behaviour in relation to environment based on past data
Propagation of heavy baryons in heavy-ion collisions
The drag and diffusion coefficients of heavy baryons ( and
) in the hadronic phase created in the latter stage of the heavy-ion
collisions at RHIC and LHC energies have been evaluated recently. In this work
we compute some experimental observables, such as the nuclear suppression
factor and the elliptic flow of heavy baryons at RHIC and LHC
energies, highlighting the role of the hadronic phase contribution to these
observables, which are going to be measured at Run 3 of LHC. For the time
evolution of the heavy quarks in the QGP and heavy baryons in the hadronic
phase we use the Langevin dynamics. For the hadronization of the heavy quarks
to heavy baryons we employ Peterson fragmentation functions. We observe a
strong suppression of both the and . We find that the
hadronic medium has a sizable impact on the heavy-baryon elliptic flow whereas
the impact of hadronic medium rescattering is almost unnoticeable on the
nuclear suppression factor. We evaluate the ratio at RHIC and
LHC. We find that ratio remain unaffected due to the hadronic
phase rescattering which enable it as a nobel probe of QGP phase dynamics along
with its hadronization.Comment: 22 pages, 15 figure
Application of remote sensing techniques for locating pelagic fish concentrations along the Kerala coast (SW coast of India) - work done and future prospects
Intensive validation programme on Potential Fishing Zone forecasts
carried out by the MARSIS, Central Marine Fisheries Research
Institute, Cochin, at 17 selectedjish landing centres along the Kerala
coast between November 1995 and May 1996 revealed a positive
relationship betwen PFZ and occurence/abundance of commercially
important pelagic fishes. An attempt is made to identify possible
reasons for the above, based on results of oceanographic itivestigations
undertaken in the area and also taking into consideration
fish behaviour in relation to environn-ieni based on past data. Future
plans for evolving a suitable prediction system for commercially
important pelagic fishes in the coastal waters of the mainland
and skipjack fishery in the Lakshadweep islands based on
PFZ forecasts are also discussed in view of its importance to the
artisanal and small mechanised sector fishermen for reducing the
searching time and thereby effecting an overall reduction in the cost
of fishing
Silymarin Protects Epidermal Keratinocytes from Ultraviolet Radiation-Induced Apoptosis and DNA Damage by Nucleotide Excision Repair Mechanism
Solar ultraviolet (UV) radiation is a well recognized epidemiologic risk factor for melanoma and non-melanoma skin cancers. This observation has been linked to the accumulation of UVB radiation-induced DNA lesions in cells, and that finally lead to the development of skin cancers. Earlier, we have shown that topical treatment of skin with silymarin, a plant flavanoid from milk thistle (Silybum marianum), inhibits photocarcinogenesis in mice; however it is less understood whether chemopreventive effect of silymarin is mediated through the repair of DNA lesions in skin cells and that protect the cells from apoptosis. Here, we show that treatment of normal human epidermal keratinocytes (NHEK) with silymarin blocks UVB-induced apoptosis of NHEK in vitro. Silymarin reduces the amount of UVB radiation-induced DNA damage as demonstrated by reduced amounts of cyclobutane pyrimidine dimers (CPDs) and as measured by comet assay, and that ultimately may lead to reduced apoptosis of NHEK. The reduction of UV radiation-induced DNA damage by silymarin appears to be related with induction of nucleotide excision repair (NER) genes, because UV radiation-induced apoptosis was not blocked by silymarin in NER-deficient human fibroblasts. Cytostaining and dot-blot analysis revealed that silymarin repaired UV-induced CPDs in NER-proficient fibroblasts from a healthy individual but did not repair UV-induced CPD-positive cells in NER-deficient fibroblasts from patients suffering from xeroderma pigmentosum complementation-A disease. Similarly, immunohistochemical analysis revealed that silymarin did not reduce the number of UVB-induced sunburn/apoptotic cells in the skin of NER-deficient mice, but reduced the number of sunburn cells in their wild-type counterparts. Together, these results suggest that silymarin exert the capacity to reduce UV radiation-induced DNA damage and, thus, prevent the harmful effects of UV radiation on the genomic stability of epidermal cells
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