9,677 research outputs found
Testing Higgs models via the vertex by a recoil method at the International Linear Collider
In general, charged Higgs bosons appear in non-minimal Higgs models.
The vertex is known to be related to the violation of the
global symmetry (custodial symmetry) in the Higgs sector. Its magnitude
strongly depends on the structure of the exotic Higgs models which contain
higher isospin representations such as triplet Higgs bosons. We study
the possibility of measuring the vertex via single charged
Higgs boson production associated with the boson at the International
Linear Collider (ILC) by using the recoil method. The feasibility of the signal
is analyzed assuming the polarized
electron and positron beams and the expected detector performance for the
resolution of the two-jet system at the ILC. The background events can be
reduced to a considerable extent by imposing the kinematic cuts even if we take
into account the initial state radiation. For a relatively light charged Higgs
boson whose mass is in the region of 120-130 GeV , the vertex would be precisely testable especially
when the decay of is lepton specific. The exoticness of the extended
Higgs sector can be explored by using combined information for this vertex and
the rho parameter.Comment: 22 pages, 23 figure
Fourier transforming a trapped Bose-Einstein condensate by waiting a quarter of the trap period: simulation and applications
We investigate the property of isotropic harmonic traps to Fourier transform a weakly interacting BoseâEinstein condensate (BEC) every quarter of a trap period. We solve the GrossâPitaevskii equation numerically to investigate the time evolution of interacting BECs in the context of the Fourier transform, and we suggest potential applications
Niacin-induced clotting factor synthesis deficiency with coagulopathy
Although coagulopathy is a well-known complication of severe niacin- induced hepatotoxic reaction, it is not found in patients with minimal aminotransferase level elevations. Three patients with significant clotting factor synthesis deficiency and coagulopathy (prothrombin times, >1.5 times control) from sustained-release niacin had only mild aminotransferase level elevations (1.5 to 2.0 times normal). In each case, protein deficiency, coagulopathy, and aminotransferase level elevation resolved promptly after withdrawal of niacin therapy. In one case, this syndrome recurred after rechallenge with sustained-release niacin, whereas the coagulopathy did not recur in a second patient rechallenged with crystalline niacin. Deficiency in protein synthesis, including coagulation factors, and coagulopathy are unrecognized complications of sustained-release niacin therapy. These cases indicate the need to measure prothrombin times routinely in patients who develop even mild aminotransferase level elevation while receiving sustained- release niacin therapy. These data are important in light of the increasing use of sustained-release niacin in the treatment of patients with lipid disorders
Surface flux drivers for the slowdown of the Atlantic Meridional Overturning Circulation in a high resolution global coupled climate model
This paper investigates the causation for the decline of the Atlantic Meridional Overturning Circulation (AMOC) from approximately 17 Sv to about 9 Sv, when the atmospheric resolution of the Max Planck Institute-Earth System Model is enhanced from âŒ1° to âŒ0.5°. The results show that the slowdown of the AMOC is caused by the cessation of deep convection. In most modeling studies, this is thought to be controlled by buoyancy fluxes in the convective regions, for example, by surface freshwater flux that is introduced locally or via enormous input from glacier or iceberg melts. While we find that freshwater is still the key to the reduction of AMOC seen in the higher-resolution run, the freshening of the North Atlantic does not need to be directly caused by local freshwater fluxes. Instead, it can be caused indirectly through winds via a reduced wind-driven gyre circulation and salinity transport associated to this circulation, as seen in the higher-resolution run. © 2019. The Authors
Response of northern North Atlantic and Atlantic meridional overturning circulation to reduced and enhanced wind stress forcing
Surface wind stress strongly influences AMOC variability on interannual time scales. On longer time scales, however, its role in AMOC variations is less clear. Here, we show a non-linear AMOC response to globally reduced and enhanced wind stress forcing, based on sensitivity experiments with MPI-ESM1.2. Under reduced wind stress forcing, the AMOC strength strongly decreases. In contrast, under enhanced wind stress forcing the AMOC strength increases only in the first decades and then decreases, stabilizing at a value similar to the reference simulation. To reveal possible mechanisms underlying this response, we assess the response of the northern North Atlantic circulation and climate to the changed wind stress forcing. Initially, the response is linear: reduced wind stress forcing weakens the gyre circulation and the associated heat and salt transport, leading to larger winter sea ice extent and a shutdown of subpolar deep convection. In the Nordic Seas, the fresher and lighter subsurface state leads to a decrease in the baroclinic pressure and the overflow strength. Under enhanced wind stress forcing, initially the opposite is happening. However, eventually subpolar surface density anomalies are determined by warmer temperature rather than increased salinity, leading to a decrease in surface density and a weakening of subpolar deep convection. The resulting AMOC weakening reduces the Atlantic inflow salinity, and subsequently the Nordic Seas baroclinic pressure and overflow strength. The quasi-equilibrium response of the northern North Atlantic circulation and climate under enhanced wind stress forcing differs from the reference simulation, even though the AMOC strength converges
âFixingâ the climate crisis: capital, states, and carbon offsetting in India
The paper analyzes dynamics of accumulation and displacement in the Clean Development Mechanism (CDM). It combines the theoretical work of David Harvey and James OâConnor with a case study of the Gujarat Fluorochemicals Limited HFC-23 destruction project in Gujarat, India. The framework is used to connect the factors driving opportunities for capital accumulation in the CDM market with the causes of social and ecological dislocation at the local project level. We argue that the CDM is a spatial fix to the ecological crisis of climate change which secures conditions of production for fossil fuel industries and promotes new sites of accumulation for other companies. The politicalâeconomic âfixâ is dependent on âfixingâ a global sociospatial divide between developed and developing countries down to âfixedâ projects at the local level. This spatial fix facilitates a displacement of the costs of responding to the climate crisis from North to South. </jats:p
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Applying the Principles of Universal Design for Learning (UDL) in the College Classroom
Universities are charged with educating students from diverse backgrounds, including ELL students, nontraditional students, military students, first generation college students, and students with disabilities. In order to meet the wide variety of learning needs and abilities in the college classroom, teachers must find innovative methods for reaching this diverse population of students. One potential solution is Universal Design for Learning (UDL). Through instructional and assessment strategies that address the âwhyâ, howâ, and âwhatâ of learning, the UDL approach ensures that all students can learn. The research regarding the concept of using UDL in the college classroom is minimal, but shows promise in meeting the needs of all students and the federal laws focusing on UDL. This article provides faculty with background information on UDL as well as ways to incorporate these strategies into their current courses
Super-transient scaling in time-delay autonomous Boolean network motifs
Autonomous Boolean networks are commonly used to model the dynamics of gene regulatory networks and allow for the prediction of stable dynamical attractors. However, most models do not account for time delays along the network links and noise, which are crucial features of real biological systems. Concentrating on two paradigmatic motifs, the toggle switch and the repressilator, we develop an experimental testbed that explicitly includes both inter-node time delays and noise using digital logic elements on field-programmable gate arrays. We observe transients that last millions to billions of characteristic time scales and scale exponentially with the amount of time delays between nodes, a phenomenon known as super-transient scaling. We develop a hybrid model that includes time delays along network links and allows for stochastic variation in the delays. Using this model, we explain the observed super-transient scaling of both motifs and recreate the experi- mentally measured transient distributions
Reinforcement-Driven Spread of Innovations and Fads
We propose kinetic models for the spread of permanent innovations and
transient fads by the mechanism of social reinforcement. Each individual can be
in one of M+1 states of awareness 0,1,2,...,M, with state M corresponding to
adopting an innovation. An individual with awareness k<M increases to k+1 by
interacting with an adopter. Starting with a single adopter, the time for an
initially unaware population of size N to adopt a permanent innovation grows as
ln(N) for M=1, and as N^{1-1/M} for M>1. The fraction of the population that
remains clueless about a transient fad after it has come and gone changes
discontinuously as a function of the fad abandonment rate lambda for M>1. The
fad dies out completely in a time that varies non-monotonically with lambda.Comment: 4 pages, 2 columns, 5 figures, revtex 4-1 format; revised version has
been expanded and put into iop format, with one figure adde
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