814,906 research outputs found
The Energy Distribution in a Static Spherically Symmetric Nonsingular Black Hole Space-Time
We calculate the energy distribution in a static spherically symmetric
nonsingular black hole space-time by using the Tolman's energy-momentum
complex. All the calculations are performed in quasi-Cartesian coordinates. The
energy distribution is positive everywhere and be equal to zero at origin. We
get the same result as obtained by Y-Ching Yang by using the Einstein's and
Weinberg's prescriptions.Comment: 5 pages, no figure
The detailed nature of active central cluster galaxies
We present detailed integral field unit (IFU) observations of the central few
kiloparsecs of the ionised nebulae surrounding four active central cluster
galaxies (CCGs) in cooling flow clusters (Abell 0496, 0780, 1644 and 2052). Our
sample consists of CCGs with H{\alpha} filaments, and have existing data from
the X-ray regime available. Here, we present the detailed optical emission-line
(and simultaneous absorption line) data over a broad wavelength range to probe
the dominant ionisation processes, excitation sources, morphology and
kinematics of the hot gas (as well as the morphology and kinematics of the
stars). This, combined with the other multiwavelength data, will form a
complete view of the different phases (hot and cold gas and stars) and how they
interact in the processes of star formation and feedback detected in central
galaxies in cooling flow clusters, as well as the influence of the host
cluster. We derive the optical dust extinction maps of the four nebulae. We
also derive a range of different kinematic properties, given the small sample
size. For Abell 0496 and 0780, we find that the stars and gas are kinematically
decoupled, and in the case of Abell 1644 we find that these components are
aligned. For Abell 2052, we find that the gaseous components show rotation even
though no rotation is apparent in the stellar components. To the degree that
our spatial resolution reveals, it appears that all the optical forbidden and
hydrogen recombination lines originate in the same gas for all the galaxies.
Based on optical diagnostic ratios ([OIII]{\lambda}5007/H{\beta} against
[NII]{\lambda}6584/H{\alpha}, [SII]{\lambda}{\lambda}6717,6731/H{\alpha}, and
[OI]{\lambda}6300/H{\alpha}), all galaxies show extended LINER emission, but
that at least one has significant Seyfert emission areas, and at least one
other has significant HII like emission line ratios for many pixels. ABRIDGED.Comment: 30 pages, accepted for publication in MNRAS. High resolution version,
with spaced figures available from autho
The Molecular Basis of Resistance Antiretroviral Markers and Polymorphisms of the Human Immunodeficiency Virus-1 Subtype Crf01-ae Protease Gene in Naïve and Treatment Failure Patients in Bali
Application of antiretrovirals (ARVs) in patients with Human Immunodeficiency Virus (HIV) infection has proven to reduce mortality rates and prolong life expectancy. On the other hand, the use of antiretroviral drugs has incited the emergence of HIVDR. The resistance is due to mutation at genes associated with drug resistance. Nowadays, the determination of resistance markers mutations are based on HIV-1 subtype B. However, the majority of HIV in Indonesia, particularly in Bali are of subtype CRF01_AE. Genetic variation between HIV viruses has led to variations in subtypes; therefore, resistance markers of subtype B could be polymorphisms of non-B subtypes. This study aims to determine the number and types of the resistance markers mutations and polymorphisms that occur on the PR gene of HIV-1 subtype CRF01_AE of naïve and treatment failure patients in Bali. This is an observational cross-sectional analytical study, conducted at two VCT clinics in Denpasar, during the period of April 2010 until October 2011. Samples consist of 18 HIV patients with treatment failure and 30 naïve HIV patients. Mutations were evaluated using PCR, sequenced and aligned were carried out using MEGA4. Interpretations of the mutations were made based on the Stanford HIV database. Hypothesis tests used were Mann-Whitney because of abnormal distribution of data. Hypothesis was accepted if the significant level p<0.05. This study found that of the demographic data, only the predisposing factors of the two groups were significantly different (p<0.05). Two patients with treatment failure and 5 naïve patients were found to have L10LV/I mutations. Only one patient with treatment failure had the I54FI mutation. No major mutations were found among the two study groups. The number and types of minor mutations were not significantly different (p>0.05) between the naïve group and treatment failure group. M36I and H69K polymorphisms of the PR gene were found in all the study samples. In conclusion of this study, two types of major mutations were found, L10LV/I and I54FI. The number and types of the resistance markers mutations towards the protease inhibitor (PI) group were not significantly different between the two study groups. M36I, H69K mutations of the PR gene are markers of polymorphisms of HIV-1 subtype CRF01_AE
Localized itinerant electrons and unique magnetic properties of SrRu2O6
SrRu2O6 has unique magnetic properties. It is characterized by a very high
N\'eel temperature, despite its quasi-two-dimensional structure, and has a
magnetic moment more than twice reduced compared to the formal ionic count.
First principles calculations show that only an ideal Neel ordering in the Ru
plane is possible, with no other metastable magnetic solutions, and, highly
unusually, yield dielectric gaps for both antiferromagnetic and nonmagnetic
states. We demonstrate that this strange behavior is the result of the
formation of very specific electronic objects, recently suggested for a
geometrically similar Na2IrO3 compound, whereby each electron is well localized
on a particular Ru6 hexagon, and completely delocalized over the corresponding
six Ru sites, thus making the compound strongly localized and highly
itinerant
Solar wind disturbances in th outer heliosphere caused by successive solar flares from the same active region
Solar wind disturbances caused by successive flares from the same active region are traced to about 20 AU, using the modeling method developed by Hakamada and Akasofu (1982). It is shown that the flare-generated shock waves coalesce with the co-rotating interaction region of the interplanetary magnetic field, resulting in a large-scale magnetic field structure in the outer heliosphere. Such a structure may have considerable effects on the propagation of galactic cosmic rays
Realization of Minimal Supergravity
Minimal supergravity mediation of supersymmetry breaking has attracted much
attention due to its simplicity, which leads to its predictive power. We
consider how Nature possibly realizes minimal supergravity through inflationary
selection of the theory. Minimality is impressively consistent with the present
observational bounds and it might be tested with the aid of low-energy soft
parameters obtained in future experiments.Comment: 18 pages, 5 figure
- …