1,002 research outputs found
Gamma-ray Constraints on Effective Interactions of the Dark Matter
Using an effective interaction approach to describe the interactions between
the dark matter particle and the light degrees of freedom of the standard
model, we calculate the gamma-ray flux due to the annihilation of the dark
matter into quarks, followed by fragmentation into neutral pions which
subsequently decay into photons. By comparison to the mid-latitude data
released from the Fermi-LAT experiment, we obtain useful constraints on the
size of the effective interactions and they are found to be comparable to those
deduced from collider, gamma-ray line and anti-matter search experiments.
However, the two operators induced by scalar and vector exchange among
fermionic dark matter and light quarks that contribute to spin-independent
cross sections are constrained more stringently by the recent XENON100 data.Comment: 22 pages, 4 figures; title fixed and a couple of references adde
Global Constraints on Effective Dark Matter Interactions: Relic Density, Direct Detection, Indirect Detection, and Collider
An effective interaction approach is used to describe the interactions
between the spin 0 or spin 1/2 dark matter particle and the degrees of freedom
of the standard model. This approach is applicable to those models in which the
dark matter particles do not experience the standard-model interactions, e.g.,
hidden-sector models. We explore the effects of these effective interaction
operators on (i) dark matter relic density, (ii) spin-independent and
spin-dependent dark matter-nucleon scattering cross sections, (iii) cosmic
antiproton and gamma ray fluxes from the galactic halo due to dark matter
annihilation, and (iv) monojet and monophoton production plus missing energy at
the Tevatron and the Large Hadron Collider (LHC). We combine the experimental
data of relic density from WMAP7, spin-independent cross section from XENON100,
spin-dependent cross section from XENON10, ZEPLIN-III, and SIMPLE, cosmic
antiproton flux from PAMELA, cosmic gamma-ray flux from -LAT, and
the monojet and monophoton data from the Tevatron and the LHC, to put the most
comprehensive limits on each effective operator.Comment: 39 pages, 10 figures; a number of references added; a new section
about applicable models is added in the appendix; treatment of data sets are
modified; comments on LEP monophoton, FERMI-LAT dSphs data, and other
discussion. arXiv admin note: substantial text overlap with arXiv:1104.532
Dynamic Candidate Keypad for Stroke-based Chinese Input Method on Touchscreen Devices
Abstract -With the popularity of touchscreen devices, physical button-based keyboards are being replaced by finger-operated virtual keyboards. Entering text on these touchscreen devices is no longer limited by finger tapping activities on the keys. Text input can be performed by finger sliding over the virtual keyboard, which is well realized by the Swype technology on a typical QWERTY keyboard. Such shorthand gesturing for text input, however, may be inefficient when directly applied to Chinese input, especially in Chinese stroke-based input method. In this paper, a novel dynamic candidate keypad with use of unidirectional finger gesture on the stroke key for character selection is proposed for enhancing stroke-based Chinese input method. The new design can enhance frequently used Chinese characters searching and input using stroke-based input. The new method is implemented on the Android 2.2 platform for performance evaluation using Traditional Chinese characters set. Experimental results show that the proposed method enables users to input popular Chinese characters easier than conventional stroke-based input methods
Distinguishing Various Models of the 125 GeV Boson in Vector Boson Fusion
The hint of a new particle around 125 GeV at the LHC through the decay modes
of diphoton and a number of others may point to quite a number of
possibilities. While at the LHC the dominant production mechanism for the Higgs
boson of the standard model and some other extensions is via the gluon fusion
process, the alternative vector boson fusion is more sensitive to electroweak
symmetry breaking through the gauge-Higgs couplings and therefore can be used
to probe for models beyond the standard model. In this work, using the well
known dijet-tagging technique to single out the vector boson fusion mechanism,
we investigate its capability to discriminate a number of models that have been
suggested to give an enhanced inclusive diphoton production rate, including the
standard model Higgs boson, fermiophobic Higgs boson, Randall-Sundrum radion,
inert-Higgs-doublet model, two-Higgs-doublet model, and the MSSM. The rates in
vector-boson fusion can give more information of the underlying models to help
distinguishing among the models.Comment: 31 pages, 3 figures; in this version some wordings are change
Trust as a mediator in the relationship between childhood sexual abuse and IL-6 level in adulthood
Childhood sexual abuse (CSA) has been shown to predict the coupling of depression and inflammation in adulthood. Trust within intimate relationships, a core element in marital relations, has been shown to predict positive physical and mental health outcomes, but the mediating role of trust in partners in the association between CSA and inflammation in adulthood requires further study. The present study aimed to examine the impact of CSA on inflammatory biomarkers (IL-6 and IL-1β) in adults with depression and the mediating role of trust. A cross-sectional survey data set of adults presenting with mood and sleep disturbance was used in the analysis. CSA demonstrated a significant negative correlation with IL-6 level (r = -0.28, p<0. 01) in adults with clinically significant depression, while trust showed a significant positive correlation with IL-6 level (r = 0.36, p < .01). Sobel test and bootstrapping revealed a significant mediating role for trust between CSA and IL-6 level. CSA and trust in partners were revealed to have significant associations with IL-6 level in adulthood. Counterintuitively, the directions of association were not those expected. Trust played a mediating role between CSA and adulthood levels of IL-6. Plausible explanations for these counterintuitive findings are discussed
Global Study of the Simplest Scalar Phantom Dark Matter Model
We present a global study of the simplest scalar phantom dark matter model.
The best fit parameters of the model are determined by simultaneously imposing
(i) relic density constraint from WMAP, (ii) 225 live days data from direct
experiment XENON100, (iii) upper limit of gamma-ray flux from Fermi-LAT
indirect detection based on dwarf spheroidal satellite galaxies, and (iv) the
Higgs boson candidate with a mass about 125 GeV and its invisible branching
ratio no larger than 40% if the decay of the Higgs boson into a pair of dark
matter is kinematically allowed. The allowed parameter space is then used to
predict annihilation cross sections for gamma-ray lines, event rates for three
processes mono-b jet, single charged lepton and two charged leptons plus
missing energies at the Large Hadron Collider, as well as to evaluate the muon
anomalous magnetic dipole moment for the model.Comment: Matches JCAP accepted version. 25 pages, 7 figure
The search for transient astrophysical neutrino emission with IceCube-DeepCore
We present the results of a search for astrophysical sources of brief transient neutrino emission using IceCube and DeepCore data acquired between 2012 May 15 and 2013 April 30. While the search methods employed in this analysis are similar to those used in previous IceCube point source searches, the data set being examined consists of a sample of predominantly sub-TeV muon-neutrinos from the Northern Sky (-5 degrees < delta < 90 degrees) obtained through a novel event selection method. This search represents a first attempt by IceCube to identify astrophysical neutrino sources in this relatively unexplored energy range. The reconstructed direction and time of arrival of neutrino events are used to search for any significant self-correlation in the data set. The data revealed no significant source of transient neutrino emission. This result has been used to construct limits at timescales ranging from roughly 1 s to 10 days for generic soft-spectra transients. We also present limits on a specific model of neutrino emission from soft jets in core-collapse supernovae
Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy
Background
A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets.
Methods
Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis.
Results
A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001).
Conclusion
We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty
No Banquet Can Do without Liquor: Alcohol counterfeiting in the People’s Republic of China
The illegal trade in alcohol has been an empirical manifestation of organised crime with a very long history; yet, the nature of the illegal trade in alcohol has received relatively limited academic attention in recent years despite the fact that it has been linked with significant tax evasion as well as serious health problems and even deaths. The current article focuses on a specific type associated with the illegal trade in alcohol, the counterfeiting of alcohol in China. The article pays particular attention to the counterfeiting of baijiu, Chinese liquor in mainland China. The aim of the article is to offer an account of the social organisation of alcohol counterfeiting business in China by illustrating the counterfeiting process, the actors in the business as well as its possible embeddedness in legal practices and industries/trades. The alcohol counterfeiting business is highly reflective to the market demand and consumer needs. Alcohol counterfeiting in China is characterised primarily by independent actors many of whom are subcontracted to provide commodities and services about the counterfeiting process. The business relies on personal networks – family and extended family members, friends and acquaintances. Relationships between actors in the business are very often based on a customer-supplier relationship or a ‘business-to-business market’. The alcohol counterfeiting business in China highlights the symbiotic relationship between illegal and legal businesses
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