355 research outputs found
Low Frequency (100-600 MHz) Searches with Axion Cavity Haloscopes
We investigate reentrant and dielectric loaded cavities for the purpose of
extending the range of axion cavity haloscopes to lower masses, below the range
where the Axion Dark Matter eXperiment (ADMX) has already searched. Reentrant
and dielectric loaded cavities were simulated numerically to calculate and
optimize their form factors and quality factors. A prototype reentrant cavity
was built and its measured properties were compared with the simulations. We
estimate the sensitivity of axion dark matter searches using reentrant and
dielectric loaded cavities inserted in the existing ADMX magnet at the
University of Washington and a large magnet being installed at Fermilab.Comment: 33 pages, 24 figure
Search for the Cosmic Axion Background with ADMX
We report the first result of a direct search for a Cosmic
Background CB - a relativistic background of axions that is not dark matter
- performed with the axion haloscope, the Axion Dark Matter eXperiment (ADMX).
Conventional haloscope analyses search for a signal with a narrow bandwidth, as
predicted for dark matter, whereas the CB will be broad. We introduce a
novel analysis strategy, which searches for a CB induced daily modulation in
the power measured by the haloscope. Using this, we repurpose data collected to
search for dark matter to set a limit on the axion photon coupling of the CB
originating from dark matter decay in the 800-995 MHz frequency range. We find
that the present sensitivity is limited by fluctuations in the cavity readout
as the instrument scans across dark matter masses. Nevertheless, we demonstrate
that these challenges can be surmounted with the use of superconducting qubits
as single photon counters, and allow ADMX to operate as a telescope searching
for axions emerging from the decay of dark matter. The daily modulation
analysis technique we introduce can be deployed for various broadband RF
signals, such as other forms of a CB or even high-frequency gravitational
waves.Comment: 9 pages, 4 figure
Non-Virialized Axion Search Sensitive to Doppler Effects in the Milky Way Halo
The Axion Dark Matter eXperiment (ADMX) has previously excluded
Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions between 680-790 MHz under the
assumption that the dark matter is described by the isothermal halo model.
However, the precise nature of the velocity distribution of dark matter is
still unknown, and alternative models have been proposed. We report the results
of a non-virialized axion search over the mass range 2.81-3.31 {\mu}eV,
corresponding to the frequency range 680-800 MHz. This analysis marks the most
sensitive search for non-virialized axions sensitive to Doppler effects in the
Milky Way Halo to date. Accounting for frequency shifts due to the detector's
motion through the Galaxy, we exclude cold flow relic axions with a velocity
dispersion of order 10^-7 c with 95% confidence
Crowd guilds: Worker-led reputation and feedback on crowdsourcing platforms
Crowd workers are distributed and decentralized. While decentralization is designed to utilize independent judgment to promote high-quality results, it paradoxically undercuts behaviors and institutions that are critical to high-quality work. Reputation is one central example: crowdsourcing systems depend on reputation scores from decentralized workers and requesters, but these scores are notoriously inflated and uninformative. In this paper, we draw inspiration from historical worker guilds (e.g., in the silk trade) to design and implement crowd guilds: centralized groups of crowd workers who collectively certify each other’s quality through double-blind peer assessment. A two-week field experiment compared crowd guilds to a traditional decentralized crowd work model. Crowd guilds produced reputation signals more strongly correlated with ground-truth worker quality than signals available on current crowd working platforms, and more accurate than in the traditional model
Rheumatoid Arthritis: Severity Classification, Factors Responsible, Pathophysiology, Current and Herbal Treatment
Rheumatoid Arthritis is the autoimmune disorder occurs due to the change in life style, improper diet plans, smoking, excessive alcohol consumption etc. It generally affects the joints and creates swelling and severe pain in joints which leads to further destruction of bone and cartilages. Due to autoimmune responses the factors like Tumor Necrosis Factor-α, Interleukins-1 are introduced to synovial and synovial membrane which creates the swelling and pain. These factors further produce reactive oxygen species and inducing osteoclasts which destruct the bone and cartilages. Along with the drugs the several natural herbal treatments are also available for the treatment of rheumatoid arthritis. This includes varies medicinal plants form which acacia species is more potent and efficient. Acacia Senegal is the plant which blocks the receptors and decreases the level of tumor necrosis factor-α. Present work on rheumatoid arthritis mainly covers classification, factors responsible, pathophysiology, severity, current treatment and its drawbacks, herbal treatment and its benefits in treatment of Rheumatoid Arthritis
The case for home based telehealth in pediatric palliative care: a systematic review
Background: Over the last decade technology has rapidly changed the ability to provide home telehealth services. At the same time, pediatric palliative care has developed as a small, but distinct speciality. Understanding the experiences of providing home telehealth services in pediatric palliative care is therefore important
Genic SNP markers and legume synteny reveal candidate genes underlying QTL for Macrophomina phaseolina resistance and maturity in cowpea [Vigna unguiculata (L) Walp.]
<p>Abstract</p> <p>Background</p> <p><it>Macrophomina phaseolina </it>is an emerging and devastating fungal pathogen that causes significant losses in crop production under high temperatures and drought stress. An increasing number of disease incidence reports highlight the wide prevalence of the pathogen around the world and its contribution toward crop yield suppression. In cowpea [<it>Vigna unguiculata </it>(L) Walp.], limited sources of low-level host resistance have been identified, the genetic basis of which is unknown. In this study we report on the identification of strong sources of host resistance to <it>M. phaseolina </it>and the genetic mapping of putative resistance loci on a cowpea genetic map comprised of gene-derived single nucleotide polymorphisms (SNPs) and amplified fragment length polymorphisms (AFLPs).</p> <p>Results</p> <p>Nine quantitative trait loci (QTLs), accounting for between 6.1 and 40.0% of the phenotypic variance (R<sup>2</sup>), were identified using plant mortality data taken over three years in field experiments and disease severity scores taken from two greenhouse experiments. Based on annotated genic SNPs as well as synteny with soybean (<it>Glycine max</it>) and <it>Medicago truncatula</it>, candidate resistance genes were found within mapped QTL intervals. QTL <it>Mac-2 </it>explained the largest percent R<sup>2 </sup>and was identified in three field and one greenhouse experiments where the QTL peak co-located with a SNP marker derived from a pectin esterase inhibitor encoding gene. Maturity effects on the expression of resistance were indicated by the co-location of <it>Mac-6 </it>and <it>Mac-7 </it>QTLs with maturity-related senescence QTLs <it>Mat-2 </it>and <it>Mat-1</it>, respectively. Homologs of the <it>ELF4 </it>and <it>FLK </it>flowering genes were found in corresponding syntenic soybean regions. Only three <it>Macrophomina </it>resistance QTLs co-located with delayed drought-induced premature senescence QTLs previously mapped in the same population, suggesting that largely different genetic mechanisms mediate cowpea response to drought stress and <it>Macrophomina </it>infection.</p> <p>Conclusion</p> <p>Effective sources of host resistance were identified in this study. QTL mapping and synteny analysis identified genomic loci harboring resistance factors and revealed candidate genes with potential for further functional genomics analysis.</p
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