7,373 research outputs found
Geometric erogdicity of a bead-spring pair with stochastic Stokes forcing
We consider a simple model for the
uctuating hydrodynamics of a
exible polymer
in dilute solution, demonstrating geometric ergodicity for a pair of particles that interact with each other through a nonlinear spring potential while being advected by a
stochastic Stokes
uid velocity field. This is a generalization of previous models which
have used linear spring forces as well as white-in-time
uid velocity fields.
We follow previous work combining control theoretic arguments, Lyapunov functions, and hypo-elliptic diffusion theory to prove exponential convergence via a Harris
chain argument. To this, we add the possibility of excluding certain "bad" sets in phase
space in which the assumptions are violated but from which the systems leaves with a
controllable probability. This allows for the treatment of singular drifts, such as those
derived from the Lennard-Jones potential, which is an novel feature of this work
Some Notes On Queenfishes And Their Fishery Along The Indian Coasts
A large variety of fishes popularly called horse mackerels, shads, trevellies, queenfishes, pompanos, runners etc. comprise the family Carangidae. Among them, the subfamily Scomberoidae represented by the
genus Scomberoides (- Chorinemus) is popularly knownas queenfishes.They form an important constituent in the marine fish landings of India. This article highlights some of the taxonomic characters for easy field identification and also to review in brief the status of fishery of this group of fishe
Turtle export from the southeast coast of India during 1945-'64 period
The Green turtle Chelonia mydas called 'Peramai'
in Tamil, a protected reptilian wildlife which
constituted about 89% of the five species of marine
turtles caught in the Gulf of Mannar and Palk Bay
were regularly exported to Sri Lanka from Pamban
and Kilakkarai Port Offices of the Gulf of Mannar
coast from 1945 to 1964. The particulars of export
are give
Gender inequality in Japan: analyzing preliminary findings from a US investment bank
Inequality occurs in every labor market, and in most nations, males expect to be paid more for producing the same work as females. This is a widely held belief in high, low context,
and sophisticated cultures. This paper aims to determine the level of gender inequality at a Japanese subsidiary of a U.S. investment bank based in Japan. The research seeks to discover how women are seen and whether they are constrained in terms of equality and advancement. Semi structured interviews are used to interpret qualitative data transcribed and categorized 23 female Japanese workers’ comments. Inequality has been revealed. Despite having greater education and experience, women were seen negatively by male co-workers. The investigation also revealed a ‘glass
ceiling.’ The study included 23 female interviews, not limiting generalization and transferability. Change in Multinational Enterprises (MNEs) should concentrate on increasing workplace equity and inclusion. MNEs might use dual-role women as role models. This study’s conclusions benefit researchers, employers, and Japanese employees seeking jobs in U.S. investment banks
A possible observational bias in the estimation of the virial parameter in virialized clumps
The dynamics of massive clumps, the environment where massive stars
originate, is still unclear. Many theories predict that these regions are in a
state of near-virial equilibrium, or near energy equi-partition, while others
predict that clumps are in a sub-virial state. Observationally, the majority of
the massive clumps are in a sub-virial state with a clear anti-correlation
between the virial parameter and the mass of the clumps ,
which suggests that the more massive objects are also the more gravitationally
bound. Although this trend is observed at all scales, from massive clouds down
to star-forming cores, theories do not predict it. In this work we show how,
starting from virialized clumps, an observational bias is introduced in the
specific case where the kinetic and the gravitational energies are estimated in
different volumes within clumps and how it can contribute to the spurious
anti-correlation in these data. As a result, the observed
effective virial parameter , and in some
circumstances it might not be representative of the virial state of the
observed clumps.Comment: A&A letter, accepte
Faecal indicator organisms in frozen prawn products. Pt. 1. Incidence and general distribution
A general survey carried out on several brands of frozen prawn products has shown that along with the standard plate count (SPC), the numbers of pathogenic organisms like Escherichia coli, enterococci and coagulase positive staphylococci have also to be taken into consideration for the evaluation of the quality of these products. No correlation could be established between the total plate count and the number of E. coli, enterococci or staphylococci. Enumeration of enterococci, however, is advocated as a better index of faecal contamination of the products than E. coli
Artemether resistance in vitro is linked to mutations in PfATP6 that also interact with mutations in PfMDR1 in travellers returning with Plasmodium falciparum infections.
BACKGROUND: Monitoring resistance phenotypes for Plasmodium falciparum, using in vitro growth assays, and relating findings to parasite genotype has proved particularly challenging for the study of resistance to artemisinins.
METHODS: Plasmodium falciparum isolates cultured from 28 returning travellers diagnosed with malaria were assessed for sensitivity to artemisinin, artemether, dihydroartemisinin and artesunate and findings related to mutations in pfatp6 and pfmdr1.
RESULTS: Resistance to artemether in vitro was significantly associated with a pfatp6 haplotype encoding two amino acid substitutions (pfatp6 A623E and S769N; (mean IC50 (95% CI) values of 8.2 (5.7 - 10.7) for A623/S769 versus 623E/769 N 13.5 (9.8 - 17.3) nM with a mean increase of 65%; p = 0.012). Increased copy number of pfmdr1 was not itself associated with increased IC50 values for artemether, but when interactions between the pfatp6 haplotype and increased copy number of pfmdr1 were examined together, a highly significant association was noted with IC50 values for artemether (mean IC50 (95% CI) values of 8.7 (5.9 - 11.6) versus 16.3 (10.7 - 21.8) nM with a mean increase of 87%; p = 0.0068). Previously described SNPs in pfmdr1 are also associated with differences in sensitivity to some artemisinins.
CONCLUSIONS: These findings were further explored in molecular modelling experiments that suggest mutations in pfatp6 are unlikely to affect differential binding of artemisinins at their proposed site, whereas there may be differences in such binding associated with mutations in pfmdr1. Implications for a hypothesis that artemisinin resistance may be exacerbated by interactions between PfATP6 and PfMDR1 and for epidemiological studies to monitor emerging resistance are discussed
Fishery and biology of yellowfin tuna occurring in the coastal fishery in Indian seas
In the recently convened Workshop on "Stock assessment of yellowfin tuna in the Indian Ocean" (FAO/IPTP, 1991) the present status of the fishery, biology and stock structure of yellawfiil tuna taken by different countries bordering the Indian Ocean have been discussed, and recommednations on the development of the fishery for this species made
Ultrafast switching time and third order nonlinear coefficients of microwave treated single walled carbon nanotube suspensions
Microwave treated water soluble and amide functionalized single walled carbon
nanotubes have been investigated using femtosecond degenerate pump-probe and
nonlinear transmission experiments. The time resolved differential transmission
using 75 femtosecond pulse with the central wavelength of 790 nm shows a
bi-exponential ultrafast photo-bleaching with time constants of of 160 fs (130
fs) and 920 fs (300 fs) for water soluble (amide functionalized) nanotubes.
Open and closed aperture z-scans show saturation absorption and positive
(negative) nonlinear refraction for water soluble (amide functionalized)
nanotubes. Two photon absorption coefficient,beata ~250 cm/GW (650 cm/GW) and
nonlinear index, gamma ~ 15 cm^2/pW (-30 cm^2/pW) are obtained from the
theoretical fit in the saturation limit to the data for two types of nanotubes.Comment: 15 pages, 4 figure
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