131 research outputs found
Mixing of scalar and tensor metric perturbations
Metric perturbations in General Relativity are usually separated into three
distinct classes: scalar, vector, and tensor. In many cases these modes are
separable, i.e. they satisfy independent equations of motion for each mode.
However, in the present paper we argue that in many cases tensor and scalar
modes are not separable, no matter what gauge conditions are chosen. The
propagation of any of these mode depends on the other. A realistic example
providing such mixing is presented.Comment: 10 page
On graviton propagation in curved space-time background
Equation describing propagation of gravitational waves (GW) over arbitrary
curved space-time background is analyzed. A new term, which is absent in the
conventional homogeneous and isotropic Friedmann cosmology, is found. Some
examples of realistic metric, where this new term manifests itself, are
presented. Possible implications to very low frequency GW are briefly
discussed.Comment: 9 page
Some questions about Teae folia (Thea sinensis L. seu Camellia sinensis L. Kuntze) as a medicinal raw material
One of the most popular plant and beverage is a Thea sinensis or Camellia sinensis (Theaceae) also known as Theae Folia or Green Tea. There are some reasons for it, such that the sensory properties, prices are relatively cheap, stimulant effects, and their potential health benefits. Motherland of this plant is considered the China. This is where people have paid attention to the ability of a decoction of the leaves have a tonic effect on the human body and the first to grow this plant. Tea folia as a medicine are made from unfermented tea leaves and young shoots. This process is fast in special drying machines. Objective: European Pharmacopoeia have monograph Green Tea and the herb that we know as a food drink have as medicine herb now. The objective of research of herbal medicine is the quality and safety of natural products. Materials and Methods: Macroscopical and microscopical features of the leaf and shoots have been analysis using an optical microscope. Phytochemical and physico-chemical analysis were evaluated. The observation of the spectrum profiles is done by interpreting the typical peak that appears. Results: Theae Folia have actinocytic stomata, unicellular trichomes, heterogenous mesophyll which is characterized by the presence of calcium oxalate crystals and sclereid cells. Phytochemical analysis indicated resources the presence of purine alkaloids caffeine and theabromine and many other drugs. The content of caffeine from Teae Folia ethanolic and water extract is differ to time. Conclusion: Pharmacognostic and phytochemicals features established in this study may be used as part of the pharmacopoeial standard, which can play an important role in its standardization
First Results from the AMoRE-Pilot neutrinoless double beta decay experiment
The Advanced Molybdenum-based Rare process Experiment (AMoRE) aims to search
for neutrinoless double beta decay (0) of Mo with
100 kg of Mo-enriched molybdenum embedded in cryogenic detectors
with a dual heat and light readout. At the current, pilot stage of the AMoRE
project we employ six calcium molybdate crystals with a total mass of 1.9 kg,
produced from Ca-depleted calcium and Mo-enriched molybdenum
(CaMoO). The simultaneous detection of
heat(phonon) and scintillation (photon) signals is realized with high
resolution metallic magnetic calorimeter sensors that operate at milli-Kelvin
temperatures. This stage of the project is carried out in the Yangyang
underground laboratory at a depth of 700 m. We report first results from the
AMoRE-Pilot search with a 111 kgd live exposure of
CaMoO crystals. No evidence for
decay of Mo is found, and a upper limit is set for the
half-life of 0 of Mo of y at 90% C.L.. This limit corresponds to an effective
Majorana neutrino mass limit in the range eV
The CCR4-NOT Complex Physically and Functionally Interacts with TRAMP and the Nuclear Exosome
BACKGROUND: Ccr4-Not is a highly conserved multi-protein complex consisting in yeast of 9 subunits, including Not5 and the major yeast deadenylase Ccr4. It has been connected functionally in the nucleus to transcription by RNA polymerase II and in the cytoplasm to mRNA degradation. However, there has been no evidence so far that this complex is important for RNA degradation in the nucleus. METHODOLOGY/PRINCIPAL FINDINGS: In this work we point to a new role for the Ccr4-Not complex in nuclear RNA metabolism. We determine the importance of the Ccr4-Not complex for the levels of non-coding nuclear RNAs, such as mis-processed and polyadenylated snoRNAs, whose turnover depends upon the nuclear exosome and TRAMP. Consistently, mutation of both the Ccr4-Not complex and the nuclear exosome results in synthetic slow growth phenotypes. We demonstrate physical interactions between the Ccr4-Not complex and the exosome. First, Not5 co-purifies with the exosome. Second, several exosome subunits co-purify with the Ccr4-Not complex. Third, the Ccr4-Not complex is important for the integrity of large exosome-containing complexes. Finally, we reveal a connection between the Ccr4-Not complex and TRAMP through the association of the Mtr4 helicase with the Ccr4-Not complex and the importance of specific subunits of Ccr4-Not for the association of Mtr4 with the nuclear exosome subunit Rrp6. CONCLUSIONS/SIGNIFICANCE: We propose a model in which the Ccr4-Not complex may provide a platform contributing to dynamic interactions between the nuclear exosome and its co-factor TRAMP. Our findings connect for the first time the different players involved in nuclear and cytoplasmic RNA degradation
Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR
Substantial experimental and theoretical efforts worldwide are devoted to
explore the phase diagram of strongly interacting matter. At LHC and top RHIC
energies, QCD matter is studied at very high temperatures and nearly vanishing
net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was
created at experiments at RHIC and LHC. The transition from the QGP back to the
hadron gas is found to be a smooth cross over. For larger net-baryon densities
and lower temperatures, it is expected that the QCD phase diagram exhibits a
rich structure, such as a first-order phase transition between hadronic and
partonic matter which terminates in a critical point, or exotic phases like
quarkyonic matter. The discovery of these landmarks would be a breakthrough in
our understanding of the strong interaction and is therefore in the focus of
various high-energy heavy-ion research programs. The Compressed Baryonic Matter
(CBM) experiment at FAIR will play a unique role in the exploration of the QCD
phase diagram in the region of high net-baryon densities, because it is
designed to run at unprecedented interaction rates. High-rate operation is the
key prerequisite for high-precision measurements of multi-differential
observables and of rare diagnostic probes which are sensitive to the dense
phase of the nuclear fireball. The goal of the CBM experiment at SIS100
(sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD
matter: the phase structure at large baryon-chemical potentials (mu_B > 500
MeV), effects of chiral symmetry, and the equation-of-state at high density as
it is expected to occur in the core of neutron stars. In this article, we
review the motivation for and the physics programme of CBM, including
activities before the start of data taking in 2022, in the context of the
worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal
Primary Cosmic Rays Energy Spectrum and Mean Mass Composition by the Data of the TAIGA Astrophysical Complex
The corrected dependence of the mean depth of the EAS maximum on
the energy was obtained from the data of the Tunka-133 array for 7 years and
the TAIGA-HiSCORE array for 2 year. The parameter ,
characterizing the mean mass compositon was derived from these results. The
differential energy spectrum of primary cosmic rays in the energy range of
- \,eV was reconstructed using the new
parameter the Cherenkov light flux at the core distance 100 m.}Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Pro
- …