25 research outputs found
Antiproton constraints on dark matter annihilations from internal electroweak bremsstrahlung
If the dark matter particle is a Majorana fermion, annihilations into two
fermions and one gauge boson could have, for some choices of the parameters of
the model, a non-negligible cross-section. Using a toy model of leptophilic
dark matter, we calculate the constraints on the annihilation cross-section
into two electrons and one weak gauge boson from the PAMELA measurements of the
cosmic antiproton-to-proton flux ratio. Furthermore, we calculate the maximal
astrophysical boost factor allowed in the Milky Way under the assumption that
the leptophilic dark matter particle is the dominant component of dark matter
in our Universe. These constraints constitute very conservative estimates on
the boost factor for more realistic models where the dark matter particle also
couples to quarks and weak gauge bosons, such as the lightest neutralino which
we also analyze for some concrete benchmark points. The limits on the
astrophysical boost factors presented here could be used to evaluate the
prospects to detect a gamma-ray signal from dark matter annihilations at
currently operating IACTs as well as in the projected CTA.Comment: 32 pages; 13 figure
PPPC 4 DM ID: A Poor Particle Physicist Cookbook for Dark Matter Indirect Detection
We provide ingredients and recipes for computing signals of TeV-scale Dark
Matter annihilations and decays in the Galaxy and beyond. For each DM channel,
we present the energy spectra of electrons and positrons, antiprotons,
antideuterons, gamma rays, neutrinos and antineutrinos e, mu, tau at
production, computed by high-statistics simulations. We estimate the Monte
Carlo uncertainty by comparing the results yielded by the Pythia and Herwig
event generators. We then provide the propagation functions for charged
particles in the Galaxy, for several DM distribution profiles and sets of
propagation parameters. Propagation of electrons and positrons is performed
with an improved semi-analytic method that takes into account
position-dependent energy losses in the Milky Way. Using such propagation
functions, we compute the energy spectra of electrons and positrons,
antiprotons and antideuterons at the location of the Earth. We then present the
gamma ray fluxes, both from prompt emission and from Inverse Compton scattering
in the galactic halo. Finally, we provide the spectra of extragalactic gamma
rays. All results are available in numerical form and ready to be consumed.Comment: 57 pages with many figures and tables. v4: updated to include a 125
higgs boson, computation and discussion of extragalactic spectra corrected,
some other typos fixed; all these corrections and updates are reflected on
the numerical ingredients available at
http://www.marcocirelli.net/PPPC4DMID.html they correspond to Release 2.
Familial aggregation and heritability of type 1 diabetes mellitus and coaggregation of chronic diseases in affected families
Purpose: To estimate the extent of familial aggregation of type 1 diabetes (T1D) and coaggregation of related chronic diseases and assess the relative contribution of environmental and genetic factors on the risks. Patients and methods: This population-based study used the Taiwan National Health Insurance database to reconstruct family structure and identify people with T1D and other chronic diseases between 1999 and 2015. Relative risks (RRs) for T1D and other chronic diseases and heritability of T1D were estimated. Heritability was estimated using the polygenic liability model. Results: Validation of family structure found the positive predictive value to be 98.7% for maternal links and 98.6% for paternal links. Having an affected twin, first-degree relative, or spouse was associated with an adjusted RR (95% CI) of 553.66 (427.59-716.89), 32.49 (28.66-36.84), and 2.17 (0.31-15.40) for T1D, respectively. Based on the polygenic liability model, heritability, shared and non-shared contributions to T1D, and variances were 66.50%, 10.86%, and 22.64%, respectively. A family history of T1D was associated with an RR (95% CI) of 1.51 (1.20-1.89) for rheumatoid arthritis, 1.66 (1.21-2.26) for Sjogren's syndrome, 1.48 (1.09-2.01) for systemic lupus erythematosus, 1.24 (1.14-1.35) for simple goiter, 1.16 (1.04-1.31) for non-toxic nodular goiter, 1.61 (1.49-1.74) for thyrotoxicosis, 1.78 (1.57-2.01) for acquired hypothyroidism, 1.66 (1.40-1.98) for thyroiditis, and 1.15 (0.97-1.37) for epilepsy. Conclusion: These data highlight the importance of the genetic contribution to T1D and confirm the coaggregation of autoimmune and metabolic diseases with T1D
Design of mobile band subsurface antenna for drainage infrastructure monitoring
This paper presents an underground subsurface wireless sensor for drainage infrastructure water level monitoring. It operates from 800 to 2170 MHz to cover the required GSM850/900, GSM1800/1900 and UMTS bands. The system consists of a wideband antenna, transceiver, data acquisition unit and an ultrasonic sensor. The proposed antenna is a 3-dimensional inverted double F antenna and has an envelope size of 90 × 63.5 × 32 mm^3 , which is acceptably small for a cramped subsurface passageway environment. The antenna design was developed using software simulation to optimise its key parameters of return loss and radiation pattern, these being evaluated both in free space and in the partially underground environment. The design developed was then realised in hardware and tested in a representative subsurface location: a utility manhole chamber. It was found that the location of the antenna in the chamber had a significant effect on its performance, but a location that was acceptable for operational purposes was found by experiment. The overall system, including a transceiver, was demonstrated to operate satisfactorily for utility monitoring purposes, including acceptable levels of path loss for communication with mobile communication base stations
Systematic Review of Medicine-Related Problems in Adult Patients with Atrial Fibrillation on Direct Oral Anticoagulants
New oral anticoagulant agents continue to emerge on the market and their safety requires assessment to provide evidence of their suitability for clinical use. There-fore, we searched standard databases to summarize the English language literature on medicine-related problems (MRPs) of direct oral anticoagulants DOACs (dabigtran, rivaroxban, apixban, and edoxban) in the treatment of adults with atri-al fibrillation. Electronic databases including Medline, Embase, International Pharmaceutical Abstract (IPA), Scopus, CINAHL, the Web of Science and Cochrane were searched from 2008 through 2016 for original articles. Studies pub-lished in English reporting MRPs of DOACs in adult patients with AF were in-cluded. Seventeen studies were identified using standardized protocols, and two reviewers serially abstracted data from each article. Most articles were inconclusive on major safety end points including major bleeding. Data on major safety end points were combined with efficacy. Most studies inconsistently reported adverse drug reactions and not adverse events or medication error, and no definitions were consistent across studies. Some harmful drug effects were not assessed in studies and may have been overlooked. Little evidence is provided on MRPs of DOACs in patients with AF and, therefore, further studies are needed to establish the safety of DOACs in real-life clinical practice
Frequency offset estimation via planar extended Kalman filter
Electronics Letters29161473-1474ELLE
Differential detection of DPSK with frequency offset compensation
10.1049/el:19940047Electronics Letters3019-10ELLE
Stress and electric field induced phase transformation phenomena in [0 1 1]-poled PZN-PT single crystals of [1 0 0]-length cut
10.1016/j.sna.2011.03.032Sensors and Actuators, A: Physical1681112-116SAAP