3,241 research outputs found
Impurity-induced frustration in correlated oxides
Using the example of Zn-doped La2CuO4, we demonstrate that a spinless
impurity doped into a non-frustrated antiferromagnet can induce substantial
frustrating interactions among the spins surrounding it. This counterintuitive
result is the key to resolving discrepancies between experimental data and
earlier theories. Analytic and quantum Monte Carlo studies of the
impurity-induced frustration are in a close accord with each other and
experiments. The mechanism proposed here should be common to other correlated
oxides as well.Comment: 4 pages, updated figures, accepted versio
Fair trade in insurance industry: Premium determination of Taiwan automobile insurance
This paper examines premium determination of voluntary automobile insurance policy and risk classification under a heavily regulated rating system in Taiwan. We investigate the distribution of actual premium and pure premium, based on unique data to test if premium reflect appropriate gender-age factor. The reasonableness of loading and the difference in driving exposure between policyholder and driver are investigated for three different
types of policy. An adjustment of gender-age premium coefficients is called for
Heavy Higgs Bosons at 14 TeV and 100 TeV
Searching for Higgs bosons beyond the Standard Model (BSM) is one of the most
important missions for hadron colliders. As a landmark of BSM physics, the MSSM
Higgs sector at the LHC is expected to be tested up to the scale of the
decoupling limit of O(1) TeV, except for a wedge region centered around
, which has been known to be difficult to probe. In this
article, we present a dedicated study testing the decoupled MSSM Higgs sector,
at the LHC and a next-generation -collider, proposing to search in channels
with associated Higgs productions, with the neutral and charged Higgs further
decaying into and , respectively. In the case of neutral Higgs we are
able to probe for the so far uncovered wedge region via . Additionally, we cover the the high range with . The combination of these searches with channels dedicated to
the low region, such as and potentially covers the full range. The search for charged
Higgs has a slightly smaller sensitivity for the moderate region,
but additionally probes for the higher and lower regions with even
greater sensitivity, via . While the LHC will be able
to probe the whole range for Higgs masses of O(1) TeV by combining
these channels, we show that a future 100 TeV -collider has a potential to
push the sensitivity reach up to TeV. In order to deal
with the novel kinematics of top quarks produced by heavy Higgs decays, the
multivariate Boosted Decision Tree (BDT) method is applied in our collider
analyses. The BDT-based tagging efficiencies of both hadronic and leptonic
top-jets, and their mutual fake rates as well as the faking rates by other jets
(, , , , etc.) are also presented.Comment: published versio
Effects of xanthine oxidase inhibitors in pulmonary hypertension associated with chronic lung disease
Exploring the role of mechanical cues in T cell function
T lymphocytes are constantly subjected to mechanical cues from their microenvironment. The
past few decades have seen a significant development in scientific research concerning the
crucial role of biophysical forces in governing various T lymphocyte-mediated processes.
Mounting research have confirmed that T lymphocyte activation is critically dependent on its
capacity to sense and respond to mechanical forces which are generated during its interaction
with cellular partners and with its microenvironment. Despite extensive research on the role
of mechanical forces on T lymphocyte biology, no dedicated T lymphocyte-intrinsic
mechanosensory module was identified until recently. In the following thesis, I have
described the role of Piezo1 mechanosensors in T lymphocyte function, particularly in the
contexts of T lymphocyte activation and migration. Upon interaction with cognate antigen
presenting cells (APCs), T lymphocytes experience significant mechanical force which
activates Piezo1 channels. Activated Piezo1 allows influx of extracellular calcium which
triggers calpain-dependent polymerisation and remodelling of the actin cytoskeletal scaffold.
This event is crucial for formation and stabilisation of the T cell-APC immunological synapse,
thereby facilitating optimal T lymphocyte activation. Moreover, Piezo1-mediated
mechanotransduction also plays a critical role in T lymphocyte chemotactic migration.
Downregulation of Piezo1 resulted in dramatically impaired motility of T lymphocytes in
response to stimulus. Thus, we have identified a previously unknown pathway of Piezo1-
mediated mechanoregulation of T lymphocyte function
Loss prevention for hog farmers: Insurance, on-farm biosecurity practices, and vaccination
Using agricultural household survey data and claim records from insurers for the year 2009, this paper analyzes hog producers' choice of means of loss prevention and identifies the relationships among biosecurity practices, vaccination, and hog insurance. By combining one probit and two structural equations, we adopt three-stage estimations on a mixed-process model to obtain the results. The findings indicate that biosecurity practices provide the basic infrastructure for operating pig farms and complement both the usage of quality vaccines and the uptake of hog insurance. In addition, there is a strong relationship of substitution between quality of vaccine and demand for hog insurance. Hog farmers that implement better biosecurity practices are more likely to seek high-quality vaccines or buy into hog insurance schemes but not both. For those households with hog insurance, better biosecurity status, better management practices, and higher-quality vaccine significantly help to reduce loss ratios. However, we also find a moral hazard effect in that higher premium expenditure by the insured households might induce larger loss ratios.Biosecurity, hog insurance, loss prevention, vaccine,
Higgs as a Slepton
In theories with TeV scale quantum gravity there is a logical possibility
where the electroweak Higgs can be a fourth generation slepton. Despite maximal
supersymmetry breaking such a scenario turns out to be tightly constrained, and
might be testable already at present collider experiments. Also, a light Higgs
is no longer a prediction of supersymmetry.Comment: 7 pages, no figures, reference adde
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