12,680 research outputs found
Spectral Decomposition of Missing Transverse Energy at Hadron Colliders
We propose a spectral decomposition to systematically extract information of
dark matter at hadron colliders. The differential cross section of events with
missing transverse energy (MET) can be expressed by a linear combination of
basis functions. In the case of -channel mediator models for dark matter
particle production, basis functions are identified with the differential cross
sections of sub-processes of virtual mediator and visible particle production
while the coefficients of basis functions correspond to dark matter invariant
mass distribution in the manner of the K\"all\'en-Lehmann spectral
decomposition. For a given MET data set and mediator model, we show that one
can differentiate a certain dark matter-mediator interaction from another
through spectral decomposition.Comment: 6+4 pages, 6 figures, PRL versio
Conditions for Generic Initial Ideals to be Almost Reverse Lexicographic
Let be a homogeneous Artinian ideal in a polynomial ring
over a field of characteristic 0. We study an equivalent
condition for the generic initial ideal \gin(I) with respect to reverse
lexicographic order to be almost reverse lexicographic. As a result, we show
that Moreno-Socias conjecture implies Fr\"{o}berg conjecture. And for the case
\Codim I \le 3, we show that has the strong Lefschetz property if and
only if \gin(I) is almost reverse lexicographic. Finally for a monomial
complete intersection Artinian ideal , we prove
that \gin(I) is almost reverse lexicographic if for each . Using this, we give a positive partial answer to
Moreno-Socias conjecture, and to Fr\"{o}berg conjecture.Comment: 10 page
STUDIES ON AZA-CYCLOADDITION:PART 1. INTRAMOLECULAR KETENE-IMINE CYCLOADDITIONPART 2. IMINIUM ION-MEDIATED [4+2] CYCLOADDITION
Part 1. Intramolecular Ketene-Imine CycloadditionThe ketene-imine cycloaddition reactions, developed previously by the Nelson group, have beenextended to the intramolecular cycloaddition of the ketene-imine cycloaddition. Initial resultsshowed that the intramolecular cycloaddition exhibited excellent enantioselectivity, but it wassuffered from poor diastereoselectivity. Later, it was shown that proper functionality on thetether of the substrate could improve diastereoselectivity.Part 2. Iminium Ion-Mediated [4+2] CycloadditionThe N-alkenyl iminium ion cycloaddition reaction (AIC reaction), developed previously by theNelson group, was further investigated for the more detailed understaniding. As a result, tworeaction pathways (Diels-Alder pathway and oxo-Diels-Alder pathway) of the AIC reaction werefound when carbamate-protected N-alkenyl iminium ion was employed as a 4Ĉ-electroncomponent. Based on this observation, efficient methods to turn off either one of the tworeaction pathways were proposed
Decreased Interleukin-4 Release from the Neurons of the Locus Coeruleus in Response to Immobilization Stress
It has been demonstrated that immobilization (IMO) stress affects neuroimmune systems followed by alterations of physiology and behavior. Interleukin-4 (IL-4), an anti-inflammatory cytokine, is known to regulate inflammation caused by immune challenge but the effect of IMO on modulation of IL-4 expression in the brain has not been assessed yet. Here, it was demonstrated that IL-4 was produced by noradrenergic neurons in the locus coeruleus (LC) of the brain and release of IL-4 was reduced in response to IMO. It was observed that IMO groups were more anxious than nontreated groups. Acute IMO (2 h/day, once) stimulated secretion of plasma corticosterone and tyrosine hydroxylase (TH) in the LC whereas these increments were diminished in exposure to chronic stress (2 h/day, 21 consecutive days). Glucocorticoid receptor (GR), TH, and IL-4-expressing cells were localized in identical neurons of the LC, indicating that hypothalamic-pituitary-adrenal- (HPA-) axis and sympathetic-adrenal-medullary- (SAM-) axis might be involved in IL-4 secretion in the stress response. Accordingly, it was concluded that stress-induced decline of IL-4 concentration from LC neurons may be related to anxiety-like behavior and an inverse relationship exists between IL-4 secretion and HPA/SAM-axes activation
Plug-in, Trainable Gate for Streamlining Arbitrary Neural Networks
Architecture optimization, which is a technique for finding an efficient
neural network that meets certain requirements, generally reduces to a set of
multiple-choice selection problems among alternative sub-structures or
parameters. The discrete nature of the selection problem, however, makes this
optimization difficult. To tackle this problem we introduce a novel concept of
a trainable gate function. The trainable gate function, which confers a
differentiable property to discretevalued variables, allows us to directly
optimize loss functions that include non-differentiable discrete values such as
0-1 selection. The proposed trainable gate can be applied to pruning. Pruning
can be carried out simply by appending the proposed trainable gate functions to
each intermediate output tensor followed by fine-tuning the overall model,
using any gradient-based training methods. So the proposed method can jointly
optimize the selection of the pruned channels while fine-tuning the weights of
the pruned model at the same time. Our experimental results demonstrate that
the proposed method efficiently optimizes arbitrary neural networks in various
tasks such as image classification, style transfer, optical flow estimation,
and neural machine translation.Comment: Accepted to AAAI 2020 (Poster
Macroeconomic and Bank-Specific Determinants of the U.S. Non-Performing Loans: Before and During the Recent Crisis
Both macroeconomic and bank-specific factors are correlated to the occurrence of Non-Performing Loans (NPL). We use a sample of U.S. banks over two distinct time periods to provide empirical evidence of various key macroeconomic and bankspecific determinants’ effects on NPLs
IL-4 Inhibits IL-1β-Induced Depressive-Like Behavior and Central Neurotransmitter Alterations
It has been known that activation of the central innate immune system or exposure to stress can disrupt balance of anti-/proinflammatory cytokines. The aim of the present study was to investigate the role of pro- and anti-inflammatory cytokines in the modulation of depressive-like behaviors, the hormonal and neurotransmitter systems in rats. We investigated whether centrally administered IL-1β is associated with activation of CNS inflammatory pathways and behavioral changes and whether treatment with IL-4 could modulate IL-1β-induced depressive-like behaviors and central neurotransmitter systems. Infusion of IL-4 significantly decreased IL-1β-induced anhedonic responses and increased social exploration and total activity. Treatment with IL-4 markedly blocked IL-1β-induced increase in PGE2 and CORT levels. Also, IL-4 reduced IL-1β-induced 5-HT levels by inhibiting tryptophan hydroxylase (TPH) mRNA and activating serotonin transporter (SERT) in the hippocampus, and levels of NE were increased by activating tyrosine hydroxylase (TH) mRNA expression. These results demonstrate that IL-4 may locally contribute to the regulation of noradrenergic and serotonergic neurotransmission and may inhibit IL-1β-induced behavioral and immunological changes. The present results suggest that IL-4 modulates IL-1β-induced depressive behavior by inhibiting IL-1β-induced central glial activation and neurotransmitter alterations. IL-4 reduced central and systemic mediatory inflammatory activation, as well as reversing the IL-1β-induced alterations in neurotransmitter levels. The present findings contribute a biochemical pathway regulated by IL-4 that may have therapeutic utility for treatment of IL-1β-induced depressive behavior and neuroinflammation which warrants further study
Stability of hydrogenation states of graphene and conditions for hydrogen spillover
The hydrogen spillover mechanism has been discussed in the field of hydrogen storage and is believed to have particular advantage over the storage as metal or chemical hydrides. We investigate conditions for practicality realizing the hydrogen spillover mechanism onto carbon surfaces, using first-principles methods. Our results show that contrary to common belief, types of hydrogenation configurations of graphene (the aggregated all-paired configurations) can satisfy the thermodynamic requirement for room-temperature hydrogen storage. However, the peculiarity of the paired adsorption modes gives rise to a large kinetic barrier against hydrogen migration and desorption. It means that an extremely high pressure is required to induce the migration-derived hydrogenation. However, if mobile catalytic particles are present inside the graphitic interstitials, hydrogen migration channels can open and the spillover phenomena can be realized. We suggest a molecular model for such a mobile catalyst which can exchange hydrogen atoms with the wall of graphene.open151
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