1,844 research outputs found
Implications of the Little Higgs Dark Matter and T-odd Fermions
We study the phenomenology of dark matter in the Littlest Higgs model with
T-parity after the discovery of Higgs boson. We analyze the relic abundance of
dark matter, focusing on the effects of coannihilaitons with T-odd fermions.
After determining the parameter space that predicts the correct relic abundance
measured by WMAP and Planck collaborations, we evaluate the elastic scattering
cross section between dark matter and nucleon. In comparison with experimental
results, we find that the lower mass of dark matter is constrained mildly by
LUX 2013 while the future XENON experiment has potential to explore most of the
parameter space for both T-odd lepton and T-odd quark coannihilation scenarios.
We also study the collider signatures of T-odd fermion pair production at the
LHC. Even though the production cross sections are large, it turns out very
challenging to search for these T-odd fermions directly at the collider because
the visible charged leptons or jets are very soft. Furthermore, we show that,
with an extra hard jet radiated out from the initial state, the T-odd quark
pair production can contribute significantly to mono-jet plus missing energy
search at the LHC
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The Association between Virus Prevalence and Intercolonial Aggression Levels in the Yellow Crazy Ant, Anoplolepis Gracilipes (Jerdon).
The recent discovery of multiple viruses in ants, along with the widespread infection of their hosts across geographic ranges, provides an excellent opportunity to test whether viral prevalence in the field is associated with the complexity of social interactions in the ant population. In this study, we examined whether the association exists between the field prevalence of a virus and the intercolonial aggression of its ant host, using the yellow crazy ant (Anoplolepis gracilipes) and its natural viral pathogen (TR44839 virus) as a model system. We delimitated the colony boundary and composition of A. gracilipes in a total of 12 study sites in Japan (Okinawa), Taiwan, and Malaysia (Penang), through intercolonial aggression assay. The spatial distribution and prevalence level of the virus was then mapped for each site. The virus occurred at a high prevalence in the surveyed colonies of Okinawa and Taiwan (100% infection rate across all sites), whereas virus prevalence was variable (30%-100%) or none (0%) at the sites in Penang. Coincidentally, colonies in Okinawa and Taiwan displayed a weak intercolonial boundary, as aggression between colonies is generally low or moderate. Contrastingly, sites in Penang were found to harbor a high proportion of mutually aggressive colonies, a pattern potentially indicative of complex colony composition. Our statistical analyses further confirmed the observed correlation, implying that intercolonial interactions likely contribute as one of the effective facilitators of/barriers to virus prevalence in the field population of this ant species
Differentiation of Foot-and-Mouth Disease-Infected pigs from Vaccinated Pigs Using Antibody-Detecting Sandwich ELISA
The presence of serum antibodies for nonstructural proteins of the foot-and-mouth disease virus (FMDV) can differentiate FMDV-infected animals from vaccinated animals. In this study, a sandwich ELISA was developed for rapid detection of the foot-and-mouth disease (FMD) antibodies; it was based on an Escherichia coli-expressed, highly conserved region of the 3ABC nonstructural protein of the FMDV O/TW/99 strain and a monoclonal antibody derived from the expressed protein. The diagnostic sensitivity of the assay was 98.4%, and the diagnostic specificity was 100% for naïve and vaccinated pigs; the detection ability of the assay was comparable those of the PrioCHECK and UBI kits. There was 97.5, 93.4 and 66.6% agreement between the results obtained from our ELISA and those obtained from the PrioCHECK, UBI and CHEKIT kits, respectively. The kappa statistics were 0.95, 0.87 and 0.37, respectively. Moreover, antibodies for nonstructural proteins of the serotypes A, C, Asia 1, SAT 1, SAT 2 and SAT 3 were also detected in bovine sera. Furthermore, the absence of cross-reactions generated by different antibody titers against the swine vesicular disease virus and vesicular stomatitis virus (VSV) was also highlighted in this assay's specificit
Comparison between Bubble CPAP and Ventilator-derived CPAP in Rabbits
BackgroundContinuous positive airway pressure (CPAP) is used in infants with respiratory distress and apnea. Bubble CPAP (B-CPAP) and ventilator-derived CPAP (V-CPAP) are two of the most popular CPAP modes, and use different pressure sources. However, few studies have been performed to compare their differences and effectiveness. This study was to determine whether B-CPAP and V-CPAP would have different effects on vital signs and arterial blood gas analysis.MethodsWe performed a randomized crossover study to measure vital signs, including mean blood pressure (MBP), heart rate (HR), and respiratory rate (RR), in 12 ketamine-anesthetized healthy rabbits receiving endotracheal intubation by tracheostomy with B-CPAP or V-CPAP. Arterial blood was also sampled and analyzed for PaO2, PaCO2, HCO3− and pH.ResultsWe observed statistically significant decreases in RR, pH and PaO2 with corresponding incrases in PaCO2 and HCO3− during the V-CPAP; however, no significant changes from baseline were observed for B-CPAP. Neither modality resulted in statistically significant changes in MBP or HR. Both forms of CPAP altered vital signs and arterial blood gases in a similar manner. There was a trend towards a lower percentage of change from baseline in all variables in B-CPAP compared with V-CPAP.ConclusionsOur results suggest that B-CPAP seems to be superior to V-CPAP in terms of its effect on arterial blood gases and vital signs. We speculate that B-CPAP could have certain protective effects that better preserve both arterial blood gases and vital signs when compared to V-CPAP. However, the results of this study still need to be tested by clinical study
A Color Based Touchless Finger Mouse
People work with computers almost anytime, everywhere  in the current trend. However, continuously controlling a computer with mouse for a long time might cause much strains to people’s wrist. This work proposes a touchless finger mouse using webcam. A marker with different colours representing different actions is used. The webcam will capture the information on the marker and trigger the associated actions. This prototype is proven to be able to perform most of the actions a normal mouser can perform
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