Radio-frequency (RF) cardiac ablation has been very successful for treating arrhythmias related with atrioventricular junction and accessory pathways with successful cure rates of more than 90%. Even ...though ventricular tachycardia (VT) is a more serious problem, it is known to be rather difficult to cure VT using RF ablation. In order to apply RF ablation to VT, we usually need to create a deeper and wider lesion. Conventional RF ablation electrodes often fail to produce such a lesion. We propose a catheter-electrode design including one or more needle electrodes with a diameter of 0.5-1.0 mm and length of 2.0-10 mm to create a lesion large enough to treat VT. One temperature sensor could be placed at the middle of the needle electrode for temperature-controlled RF ablation. From finite element analyses and in vitro experiments, we found that the depth of a lesion is 1-2 mm deeper than the insertion depth of the needle and the width increases as we increase the diameter of the needle and the time duration. We showed that a single needle electrode can produce a lesion with about 10-mm width and any required depth. If a wider lesion is required, more than one needle with suggested structures can be used. Or, repeated RF ablations around a certain area using one needle could produce a cluster of lesions. In some cases, a catheter with both conventional electrode and needle electrode at its tip may be beneficial to take advantage of both types of electrode.
Predicting future climate change over a region of complex terrain, such as the western United States (US), remains challenging due to the low resolution of global climate models (GCMs). Yet the ...climate extremes of recent years in this region, such as floods, wildfires, and drought, are likely to intensify further as climate warms, underscoring the need for high-quality and high-resolution predictions. Here, we present an ensemble of dynamically downscaled simulations over the western US from 1980-2100 at 9 km grid spacing, driven by 16 latest-generation GCMs. This dataset is titled the Western US Dynamically Downscaled Dataset (WUS-D3).
Radio-frequency (RF) cardiac catheter ablation has been very successful for treating some cardiac arrhythmias, however, the success rate for ventricular tachycardias is still not satisfactory. Some ...existing methods for developing deeper lesions include active cooling of the electrode and modifying the electrode shape. We propose a method of noncontact ablation, to solve this problem. We apply 120 W of power through an 8-mm electrode for a 120-s duration, with distances from 0 to 3 mm between electrode and myocardium, to create lesions in myocardium. We apply flow rates of 1, 3, and 5 L/min to determine their effect. Results show that with an optimal distance from 0.5 to 1.5 mm between electrode and myocardium, we increase lesion depth from 7.5 mm for contact ablation to 9.5 mm for noncontact ablation. For different flow rates, the optimal distance various. The effect of flow rate is not obvious. Higher flow rate does not lead to a deeper lesion.
Additional jet activity in dijet events is measured using Formula: see text collisions at ATLAS at a centre-of-mass energy of Formula: see text, for jets reconstructed using the Formula: see text ...algorithm with radius parameter Formula: see text. This is done using variables such as the fraction of dijet events without an additional jet in the rapidity interval bounded by the dijet subsystem and correlations between the azimuthal angles of the dijet s. They are presented, both with and without a veto on additional jet activity in the rapidity interval, as a function of the scalar average of the transverse momenta of the dijet s and of the rapidity interval size. The double differential dijet cross section is also measured as a function of the interval size and the azimuthal angle between the dijet s. These variables probe differences in the approach to resummation of large logarithms when performing QCD calculations. The data are compared to powheg, interfaced to the pythia 8 and herwig parton shower generators, as well as to hej with and without interfacing it to the ariadne parton shower generator. None of the theoretical predictions agree with the data across the full phase-space considered; however, powheg+pythia 8 and hej+ariadne are found to provide the best agreement with the data. These measurements use the full data sample collected with the ATLAS detector in Formula: see textFormula: see text collisions at the LHC and correspond to integrated luminosities of Formula: see text and Formula: see text for data collected during 2010 and 2011, respectively.
A search is presented for the pair production of light scalar top quarks in
proton–proton collisions recorded with the ATLAS detector at the Large Hadron Collider. This analysis uses the full data ...sample collected during 2011 running that corresponds to a total integrated luminosity of 4.7 fb
−1
. Light scalar top quarks are searched for in events with two opposite-sign leptons (
e
,
μ
), large missing transverse momentum and at least one jet in the final state. No excess over Standard Model expectations is found, and the results are interpreted under the assumption that the light scalar top decays to a
b
-quark in addition to an on-shell chargino whose decay occurs through a virtual
W
boson. If the chargino mass is 106 GeV, light scalar top-quark masses up to 130 GeV are excluded for neutralino masses below 70 GeV.
A measurement of event shape variables is presented for large momentum transfer proton-proton collisions using the ATLAS detector at the Large Hadron Collider. Six event shape variables calculated ...using hadronic jets are studied in inclusive multi-jet events in 35 pb
−1
of integrated luminosity at a center-of-mass energy of
. These measurements are compared to predictions by three Monte Carlo event generators containing leading-logarithmic parton showers matched to leading order matrix elements for 2→2 and 2→
n
(
n
=2,…,6) scattering. Measurements of the third-jet resolution parameter, aplanarity, thrust, sphericity, and transverse sphericity are generally well described. The mean value of each event shape variable is evaluated as a function of the average momentum of the two leading jets
p
T,1
and
p
T,2
, with a mean
p
T
approaching 1 TeV.
The results of a search for the production of second generation scalar leptoquarks are presented for final states consisting of either two muons and at least two jets or a muon plus missing ...transverse momentum and at least two jets. A total of 1.03 fb
−1
integrated luminosity of proton-proton collision data produced by the Large Hadron Collider at
and recorded by the ATLAS detector is used for the search. The event yields in the signal regions are found to be consistent with the Standard Model background expectations. The production of second generation leptoquarks is excluded for a leptoquark mass
m
LQ
<594 (685) GeV at 95 % confidence level, for a branching ratio of 0.5 (1.0) for leptoquark decay to a muon and a quark.
This paper describes an analysis of the angular distribution of
W
→
eν
and
W
→
μν
decays, using data from
pp
collisions at
recorded with the ATLAS detector at the LHC in 2010, corresponding to an ...integrated luminosity of about 35 pb
−1
. Using the decay lepton transverse momentum and the missing transverse momentum, the
W
decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions
f
0
,
f
L
and
f
R
over two ranges of
W
transverse momentum
and
. Good agreement is found with theoretical predictions. For
, the values of
f
0
and
f
L
−
f
R
, averaged over charge and lepton flavour, are measured to be:
f
0
=0.127±0.030±0.108 and
f
L
−
f
R
=0.252±0.017±0.030, where the first uncertainties are statistical, and the second include all systematic effects.
To quantify the impact of tiling workmanship on the performance of tiled facades, the Singapore building authority launched a research project to review and investigate the entire process of external ...wall tiling. As part of this effort, field investigation and laboratory experiment were conducted. The field investigation was specially featured by conducting in-situ pull-off tests on tiled walls of an 11-year-old building. Evidence was obtained by statistically correlating the bond-strength reduction with various signs of inadequate workmanship. However, the bona fide workmanship impact became confused with the weathering effect. To distinguish the two, tiled specimens were carefully fabricated for laboratory experiments. Before being destructively tested, most of the specimens were subjected to a closed-loop-controlled artificial weathering. These tests revealed that bonding strength plunged as the quality of workmanship declined. Although the weathering effect was quite moderate in the specimens prepared with very good workmanship, the synergistic effect of the weathering together with inadequate workmanship was disastrous.
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