9,628 research outputs found
GiRaFFE: An Open-Source General Relativistic Force-Free Electrodynamics Code
We present GiRaFFE, the first open-source general relativistic force-free
electrodynamics (GRFFE) code for dynamical, numerical-relativity generated
spacetimes. GiRaFFE adopts the strategy pioneered by McKinney and modified by
Paschalidis and Shapiro to convert a GR magnetohydrodynamic (GRMHD) code into a
GRFFE code. In short, GiRaFFE exists as a modification of IllinoisGRMHD, a
user-friendly, open-source, dynamical-spacetime GRMHD code. Both GiRaFFE and
IllinoisGRMHD leverage the Einstein Toolkit's highly-scalable infrastructure to
make possible large-scale simulations of magnetized plasmas in strong,
dynamical spacetimes on adaptive-mesh refinement (AMR) grids. We demonstrate
that GiRaFFE passes a large suite of both flat and curved-spacetime code tests
passed by a number of other state-of-the-art GRFFE codes, and is thus ready for
production-scale simulations of GRFFE phenomena of key interest to relativistic
astrophysics.Comment: 23 pages, 4 figures. Consistent with published versio
Observation of Muon Neutrino Disappearance with the MINOS Detectors in the NuMI Neutrino Beam
This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current ν_μ interactions are compared in two detectors located along the beam axis at distances of 1 and 735 km. With 1.27×10^(20) 120 GeV protons incident on the NuMI target, 215 events with energies below 30 GeV are observed at the Far Detector, compared to an expectation of 336±14 events. The data are consistent with ν_μ disappearance via oscillations with Δm_(32)^2|=2.74_(-0.26)^(+0.44)×10^(-3)  eV^2 and sin^2(2θ_(23))>0.87 (68% C.L.)
First observations of separated atmospheric ν_μ and ν̅ _μ events in the MINOS detector
The complete 5.4 kton MINOS far detector has been taking data since the beginning of August 2003 at a
depth of 2070 meters water-equivalent in the Soudan mine, Minnesota. This paper presents the first
MINOS observations of ν_μ and ν̅ _μ charged-current atmospheric neutrino interactions based on an
exposure of 418 days. The ratio of upward- to downward-going events in the data is compared to the
Monte Carlo expectation in the absence of neutrino oscillations, giving R^(data)_(up/down/R^(MC)_(up/down) =
0:62^(+0.19)_(0:14)(stat.) ± 0.02(sys.). An extended maximum likelihood analysis of the observed L/E distributions
excludes the null hypothesis of no neutrino oscillations at the 98% confidence level. Using the curvature of
the observed muons in the 1.3 T MINOS magnetic field ν_μ and ν̅ _μ interactions are separated. The ratio of
ν̅ _μ to ν_μ events in the data is compared to the Monte Carlo expectation assuming neutrinos and
antineutrinos oscillate in the same manner, giving R^(data)_(ν_μ/ν̅ _μ) / R^(MC)_(ν_μ/ν̅ _μ) = 0.96^(+0:38)_(0.27)(stat.) ± 0.15(sys.), where
the errors are the statistical and systematic uncertainties. Although the statistics are limited, this is the first
direct observation of atmospheric neutrino interactions separately for ν_μ and ν̅ _μ
Eco-friendly fishing methods and techniques practiced in the northern hills zone of Chhattisgarh state, India
Indian forests have the potential to safeguard the livelihood of forest dwelling people, particularly tribal people, who are among the most disadvantaged groups in our society. Tribal people generally depend on forests for their cultural, spiritual, and to varying degree of economic needs. Fishing is one of the important livelihood activities of the tribal community since the time immortal. Fishing provides the source of livelihood as well as nutritional security to the tribal family significantly. An explorative study was conducted in participatory mode to explore the eco-friendly fishing methods. Totally, 300 respondents were selected for this study. The data was documented with the help of participatory observation, focused group discussions with triangulation procedures. In the paper, eco-friendly fishing methods such as Kumani, Pahata, Mora, Donga, Pelna, Choppa, Mora, Gulel, Bhawarjal, Ditori, Beetaah, Chiwaar, Baahla and Jholna and their working procedures are discussed. Jholna used to catch small and medium sized fishes upto 5-7 kg/day. The production cost of this choppa is less than Rs. 250 and it is used to catch small sized fishes up to 1.5-2.5kg/day. Kumani is used to catch small sized fishes and crabs upto 1-2 kg/day. The making cost of Pelna is around Rs. 650 and it is used to catch fishes upto 6-7 kg/day. The construction cost of Pahata gear is around Rs. 2000 and It is used to catch medium to big sized fishes upto 8-10kg/day
An exploratory study on cultural and health significance of traditional tattooing practices among tribal community in Chhattisgarh state, India
This explorative study carried out from four districts of Chhattisgarh state namely Surajpur, Surguja, Balrampur and Jashpur. From each district, four villages were selected and from each village 25 tribal respondents were selected thus 300 respondents were selected for this study. About 65.33 percent of the tribal were between 36and 50 years of age group, more than one fourth (34.67%) of the farmers were educated up to primary school level, about half (49.00 %) of the respondents were at the income range of Rs. 25,001 to Rs. 75,000 and about 80% of the population of the state is rural and the main livelihood of the villagers is agriculture and agriculture-based small industry. Tattooing is one of the livelihood option for the tribal community in the study area. Tattooing has been practiced across the world since at least Neolithic times (7000 BCE), as confirmed by mummified preserved skin, prehistoric art, literatures, poetry, proverbs and the archaeological records. In Southern India, permanent tattoos are called pachakutharathu. In northern India, permanent tattoos are called Godna. Tattoos have been used as cultural symbols among many tribal populations, as well as the caste-based Hindu population of India. These tattoos have also been used as integral part of the tribal’s lifestyle Chhattisgarh state of India
Generic effective source for scalar self-force calculations
A leading approach to the modelling of extreme mass ratio inspirals involves
the treatment of the smaller mass as a point particle and the computation of a
regularized self-force acting on that particle. In turn, this computation
requires knowledge of the regularized retarded field generated by the particle.
A direct calculation of this regularized field may be achieved by replacing the
point particle with an effective source and solving directly a wave equation
for the regularized field. This has the advantage that all quantities are
finite and require no further regularization. In this work, we present a method
for computing an effective source which is finite and continuous everywhere,
and which is valid for a scalar point particle in arbitrary geodesic motion in
an arbitrary background spacetime. We explain in detail various technical and
practical considerations that underlie its use in several numerical self-force
calculations. We consider as examples the cases of a particle in a circular
orbit about Schwarzschild and Kerr black holes, and also the case of a particle
following a generic time-like geodesic about a highly spinning Kerr black hole.
We provide numerical C code for computing an effective source for various
orbital configurations about Schwarzschild and Kerr black holes.Comment: 24 pages, 7 figures, final published versio
Mol. Cell. Proteomics
Post-translational modification of proteins by ubiquitin is a fundamentally important regulatory mechanism. However, proteome-wide analysis of endogenous ubiquitylation remains a challenging task, and almost always has relied on cells expressing affinity tagged ubiquitin. Here we combine single-step immunoenrichment of ubiquitylated peptides with peptide fractionation and high-resolution mass spectrometry to investigate endogenous ubiquitylation sites. We precisely map 11,054 endogenous putative ubiquitylation sites (diglycine-modified lysines) on 4,273 human proteins. The presented data set covers 67% of the known ubiquitylation sites and contains 10,254 novel sites on proteins with diverse cellular functions including cell signaling, receptor endocytosis, DNA replication, DNA damage repair, and cell cycle progression. Our method enables site-specific quantification of ubiquitylation in response to cellular perturbations and is applicable to any cell type or tissue. Global quantification of ubiquitylation in cells treated with the proteasome inhibitor MG-132 discovers sites that are involved in proteasomal degradation, and suggests a nonproteasomal function for almost half of all sites. Surprisingly, ubiquitylation of about 15% of sites decreased more than twofold within four hours of MG-132 treatment, showing that inhibition of proteasomal function can dramatically reduce ubiquitylation on many sites with non-proteasomal functions. Comparison of ubiquitylation sites with acetylation sites reveals an extensive overlap between the lysine residues targeted by these two modifications. However, the crosstalk between these two post-translational modifications is significantly less frequent on sites that show increased ubiquitylation upon proteasome inhibition. Taken together, we report the largest site-specific ubiquitylation dataset in human cells, and for the first time demonstrate proteome-wide, site-specific quantification of endogenous putative ubiquitylation sites
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