177 research outputs found
Stellar Filaments in Self-Interacting Brans-Dicke Gravity
This paper is devoted to study cylindrically symmetric stellar filaments in
self-interacting Brans-Dicke gravity. For this purpose, we construct polytropic
filamentary models through generalized Lane-Emden equation in Newtonian regime.
The resulting models depend upon the values of cosmological constant (due to
scalar field) along with polytropic index and represent a generalization of the
corresponding models in general relativity. We also investigate fragmentation
of filaments by exploring the radial oscillations through stability analysis.
This stability criteria depends only upon the adiabatic index.Comment: 21 pages, 4 figures, accepted for publication in EPJ
Dynamics of Axial Symmetric System in Self-Interacting Brans-Dicke Gravity
This paper investigates dynamics of axial reflection symmetric model in
self-interacting Brans-Dicke gravity for anisotropic fluid. We formulate
hydrodynamical equations and discuss oscillations using time-dependent
perturbation for both spin as well as spin-independent cases. The expressions
of frequency, total energy density and equation of motion of oscillating model
are obtained. We study instability of oscillating models in weak
approximations. It is found that the oscillations and stability of the model
depend upon the dark energy source along with anisotropy and reflection
effects. We conclude that the axial reflection system remains stable for
stiffness parameter , collapses for and becomes unstable
for .Comment: 24 pages, no figure, accepted for publication in publication in Eur.
Phys. J.
Pre-discovery and Follow-up Observations of the Nearby SN 2009nr: Implications for Prompt Type Ia SNe
We present photometric and spectroscopic observations of the Type Ia
supernova SN 2009nr in UGC 8255 (z=0.0122). Following the discovery
announcement at what turned out to be ten days after peak, we detected it at V
~15.7 mag in data collected by the All Sky Automated Survey (ASAS) North
telescope 2 weeks prior to the peak, and then followed it up with telescopes
ranging in aperture from 10-cm to 6.5-m. Using early photometric data available
only from ASAS, we find that the SN is similar to the over-luminous Type Ia SN
1991T, with a peak at Mv=-19.6 mag, and a slow decline rate of Dm_15(B)=0.95
mag. The early post-maximum spectra closely resemble those of SN 1991T, while
the late time spectra are more similar to those of normal Type Ia SNe.
Interestingly, SN 2009nr has a projected distance of 13.0 kpc (~4.3 disk scale
lengths) from the nucleus of the small star-forming host galaxy UGC 8255. This
indicates that the progenitor of SN 2009nr is not associated with a young
stellar population, calling into question the conventional association of
luminous SNe Ia with the "prompt" component directly correlated with current
star formation. The pre-discovery observation of SN 2009nr using ASAS
demonstrates the science utility of high cadence all sky surveys conducted
using small telescopes for the discovery of nearby (d=<50 Mpc) supernovae.Comment: 11 pages, 11 figures, 4 tables. Accepted for publication in ApJ on
11/02/201
Population genetic portrait of Pakistani Lahore-Christians based on 32 STR loci.
Phylogenetic relationship and the population structure of 500 individuals from the Christian community of Lahore, Pakistan, were examined based on 15 autosomal short tandem repeats (STRs) using the AmpFℓSTR Identifiler Plus PCR Amplification Kit and our previously published Y-filer kit data (17 Y-STRs) of same samples. A total of 147 alleles were observed in 15 loci and allele 11 at the TPOX locus was the most frequent with frequency value (0.464). The data revealed that the Christian population has unique genetic characteristics with respect to a few unusual alleles and their frequencies relative to the other Pakistani population. Significant deviations from Hardy-Weinberg equilibrium were found at two loci (D13S317, D18S51) after Boneferroni's correction (p ≤ 0.003). The combined power of discrimination, combined power of exclusion and cumulative probability of matching were 0.999999999999999978430815060354, 0.999995039393942 and 2.15692 × 10-17, respectively. On the bases of genetic distances, PCA, phylogenetic and structure analysis Lahore-Christians appeared genetically more associated to south Asian particularly Indian populations like Tamil, Karnataka, Kerala and Andhra Pradesh than rest of global populations
2-Methylamino-5-nitrobenzoic acid
The title compound, C8H8N2O4, is almost planar (r.m.s. deviation = 0.037 Å) and an intramolecular N—H⋯O hydrogen bond generates an S(6) ring. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds generate R
2
2(8) loops. Intermolecular N—H⋯O hydrogen bonds (involving the same H atom that forms the intramolecular hydrogen bond) link the dimers into infinite sheets lying parallel to (102)
Australian mental health care practitioners' construing of non-White and White people : implications for cultural competence and therapeutic alliance
Background: The development of cultural competence is central to the therapeutic alliance with clients from diverse backgrounds. Given that the majority of Australia’s population growth is due to migration, mental health practitioner construing of non-White and White people has a significant role and impact on client engagement. Method: To examine the impact of mental health practitioner construing on their strategies for cultural competence and the therapeutic alliance, 20 White and non-White mental health practitioners and trainees providing mental health services were purposively sampled and interviewed face-to-face or via videoconferencing. Data was analysed thematically and the impact of construing on practitioner cultural competence and the therapeutic alliance were interpreted using Personal Construct Psychology. Results: Practitioners demonstrated cultural competence in their acknowledgement of the impact of negative construing of ethnic, cultural, religious, social, racial and linguistic diversity on client wellbeing. Practitioners sought to address these negative impacts on clients by drawing on the client-practitioner relationship to improve the therapeutic alliance. Conclusions: The results reinforce the need for mental health care workers to develop cultural competence with a focus on developing awareness of the impact of frameworks of Whiteness on the experiences of non-White people. This is central to the development of a therapeutic alliance where clients feel understood and assured that their mental health concerns will not be constructed (and treated) through a framework that constrains both White and non-White people’s opportunities for improved mental health and wellbeing
60 Gbps real-time wireless communications at 300 GHz carrier using a Kerr microcomb
Future wireless communication infrastructure will rely on terahertz systems
that can support an increasing demand for large-bandwidth, ultra-fast wireless
data transfer. In order to satisfy this demand, compact, low-power, and low
noise sources of terahertz radiation are being developed. A promising route to
achieving this goal is combining photonic-integrated optical frequency combs
with fast photodiodes for difference frequency generation in the THz. Here, we
demonstrate wireless communications using a 300 GHz carrier wave generated via
photomixing of two optical tones originating from diode lasers that are
injection locked to a dissipative Kerr soliton frequency microcomb. We achieve
transfer rates of 80 Gbps using homodyne detection and 60 Gbps transmitting
simultaneously both data and clock signals in a dual-path wireless link. This
experimental demonstration paves a path towards low-noise and integrated
photonic millimeter-wave transceivers for future wireless communication
systems
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