97 research outputs found
Supersymmetry breaking and gauge mediation in models with a generic superpotential
We present a general scheme for finding or creating a metastable vacuum in
supersymmetric theories. By using the formalism, we show that there is a
parameter region where a metastable vacuum exists in the Wess-Zumino model
coupled to messenger fields. This model serves as a perturbative renormalizable
model of direct gauge mediation.Comment: 13 pages, 1 figures. v2 two loop corrections and references added. to
appear in PL
Supersymmetry Breaking and Gauge Mediation
We review recent works on supersymmetry breaking and gauge mediation. We
survey our current understanding of dynamical supersymmetry breaking mechanisms
and describe new model building tools using duality, meta-stability, and
stringy construction. We discuss phenomenological constraints and their
solutions, paying attentions to issues with gaugino masses and electroweak
symmetry breaking.Comment: 42 pages, 9 figures, invited review to appear in Annu. Rev. Nucl.
Part. Sci. v2: references adde
RNA sequencing reveals small RNAs differentially expressed between incipient Japanese threespine sticklebacks
BACKGROUND: Non-coding small RNAs, ranging from 20 to 30 nucleotides in length, mediate the regulation of gene expression and play important roles in many biological processes. One class of small RNAs, microRNAs (miRNAs), are highly conserved across taxa and mediate the regulation of the chromatin state and the post-transcriptional regulation of messenger RNA (mRNA). Another class of small RNAs is the Piwi-interacting RNAs, which play important roles in the silencing of transposons and other functional genes. Although the biological functions of the different small RNAs have been elucidated in several laboratory animals, little is known regarding naturally occurring variation in small RNA transcriptomes among closely related species. RESULTS: We employed next-generation sequencing technology to compare the expression profiles of brain small RNAs between sympatric species of the Japanese threespine stickleback (Gasterosteus aculeatus). We identified several small RNAs that were differentially expressed between sympatric Pacific Ocean and Japan Sea sticklebacks. Potential targets of several small RNAs were identified as repetitive sequences. Female-biased miRNA expression from the old X chromosome was also observed, and it was attributed to the degeneration of the Y chromosome. CONCLUSIONS: Our results suggest that expression patterns of small RNA can differ between incipient species and may be a potential mechanism underlying differential mRNA expression and transposon activity
Direct Mediation of Meta-Stable Supersymmetry Breaking
The supersymmetric SU(Nc) Yang-Mills theory coupled to Nf matter fields in
the fundamental representation has meta-stable vacua with broken supersymmetry
when Nc < Nf < 3/2 Nc. By gauging the flavor symmetry, this model can be
coupled directly to the standard model. We show that it is possible to make a
slight deformation to the model so that gaugino masses are generated and the
Landau pole problem can be avoided. The deformed model has simple realizations
on intersecting branes in string theory, where various features of the
meta-stable vacua are encoded geometrically as brane configurations.Comment: 22 pages, 4 figures, a reference added, version to appear in PR
Gauge Mediation in String Theory
We show that a large class of phenomenologically viable models for gauge
mediation of supersymmetry breaking based on meta-stable vacua can be realized
in local Calabi-Yau compactifications of string theory.Comment: 7 pages, 1 figure, harvmac. v2: references added and typos correcte
Patients with CDH23 mutations and the 1555A > G mitochondrial mutation are good candidates for electric acoustic stimulation (EAS)
Conclusions: CDH23 mutations and the 1555A>G mitochondrial mutation were identified among our series of electric acoustic stimulation (EAS) patients, confirming that these genes were important in hearing loss with involvement of high frequency. Successful hearing preservation as well as good outcomes from EAS indicated that patients with this combination of mutations are good candidates for EAS. Objectives: Screening for gene mutations that possibly cause hearing loss involving high frequency was performed to identify the responsible genes in patients with EAS. In addition to a review of the genetic background of the patients with residual hearing loss, the benefit of EAS for patients with particular gene mutations was evaluated. Methods: Eighteen patients (15 late-onset, 3 early-onset) with residual hearing who had received EAS were included in this study. Genetic analysis was performed to identify GJB2, CDH23, SLC26A4, and the 1555 mitochondrial mutations. Results: Three early-onset patients had CDH23 mutations. One late-onset patient had the 1555 A>G mitochondrial mutation.ArticleACTA OTO-LARYNGOLOGICA. 132(4):377-384 (2012)journal articl
Metastable Vacua in Perturbed Seiberg-Witten Theories, Part 2: Fayet-Iliopoulos Terms and K\"ahler Normal Coordinates
We show that the perturbation of an N=2 supersymmetric gauge theory by a
superpotential linear in the Kahler normal coordinates of the Coulomb branch,
discussed in arXiv:0704.3613, is equivalent to the perturbation by
Fayet-Iliopoulos terms. It follows that the would-be meta-stable vacuum at the
origin of the normal coordinates in fact preserves N=1 supersymmetry unless the
superpotential is truncated to a finite-degree polynomial of the adjoint scalar
fields. We examine the criteria for supersymmetry breaking under a perturbation
by Fayet-Iliopoulos terms and present a general classification of
non-supersymmetric critical points. In some explicit examples, we are also able
to study local stability of these points and demonstrate that, if the
perturbation is chosen appropriately, they indeed correspond to
supersymmetry-breaking vacua. Relations of these constructions to flux
compactifications and geometric meta-stability are also discussed.Comment: 25 page
経頚静脈的管肝内門脈大循環短絡術による portal hypertensive gastropathy の変化
金沢大学医学系研究科荻野, 英
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