76 research outputs found
An 3d-3d Correspondence
M5-branes on an associative three-cycle in a -holonomy manifold
give rise to a 3d supersymmetric gauge theory,
. We propose an 3d-3d correspondence,
based on two observables of these theories: the Witten index and the
-partition function. The Witten index of a 3d theory
is shown to be computed in terms of the partition
function of a topological field theory, a super-BF-model coupled to a spinorial
hypermultiplet (BFH), on . The BFH-model localizes on solutions to a
generalized set of 3d Seiberg-Witten equations on . Evidence to support
this correspondence is provided in the abelian case, as well as in terms of a
direct derivation of the topological field theory by twisted dimensional
reduction of the 6d theory. We also consider a correspondence for the
-partition function of the theories, by
determining the dimensional reduction of the M5-brane theory on . The
resulting topological theory is Chern-Simons-Dirac theory, for a gauge field
and a twisted harmonic spinor on , whose equations of motion are the
generalized 3d Seiberg-Witten equations. For generic -manifolds the theory
reduces to real Chern-Simons theory, in which case we conjecture that the
-partition function of is given by the
Witten-Reshetikhin-Turaev invariant of .Comment: 63 pages, 4 figures; v2: JHEP versio
M5-branes on S^2 x M_4: Nahm's Equations and 4d Topological Sigma-models
We study the 6d N=(0,2) superconformal field theory, which describes multiple
M5-branes, on the product space S^2 x M_4, and suggest a correspondence between
a 2d N=(0,2) half-twisted gauge theory on S^2 and a topological sigma-model on
the four-manifold M_4. To set up this correspondence, we determine in this
paper the dimensional reduction of the 6d N=(0,2) theory on a two-sphere and
derive that the four-dimensional theory is a sigma-model into the moduli space
of solutions to Nahm's equations, or equivalently the moduli space of
k-centered SU(2) monopoles, where k is the number of M5-branes. We proceed in
three steps: we reduce the 6d abelian theory to a 5d Super-Yang-Mills theory on
I x M_4, with I an interval, then non-abelianize the 5d theory and finally
reduce this to 4d. In the special case, when M_4 is a Hyper-Kahler manifold, we
show that the dimensional reduction gives rise to a topological sigma-model
based on tri-holomorphic maps. Deriving the theory on a general M_4 requires
knowledge of the metric of the target space. For k=2 the target space is the
Atiyah-Hitchin manifold and we twist the theory to obtain a topological
sigma-model, which has both scalar fields and self-dual two-forms.Comment: 78 pages, 2 figure
F-theory and AdS_3/CFT_2
We construct supersymmetric AdS_3 solutions in F-theory, that is Type IIB
supergravity with varying axio-dilaton, which are holographically dual to 2d
N=(0,4) superconformal field theories with small superconformal algebra. In
F-theory these arise from D3-branes wrapped on curves in the base of an
elliptically fibered Calabi-Yau threefold Y_3 and correspond to strings in the
6d N=(1,0) theory obtained from F-theory on Y_3. The non-trivial fibration over
the wrapped curves implies a varying coupling of the N=4 Super-Yang-Mills
theory on the D3-branes. We compute the holographic central charges and show
that these agree with the field theory and with the anomalies of self-dual
strings in 6d. We complement our analysis with a discussion of the dual
M-theory solutions and a comparison of the central charges.Comment: 83 pages, v2: references added, typos correcte
Bir kırmızı, bir sarı gül ve Gülbaba
Taha Toros Arşivi, Dosya Adı: Galatasarayİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033
Host selection of hematophagous leeches (Haemadipsa japonica): Implications for iDNA studies
The development of an efficient and cost‐effective method for monitoring animal populations or biodiversity is urgently needed, and invertebrate‐derived DNA (iDNA) may offer a promising tool for assessing the diversity and other ecological information of vertebrates. We studied the host species of a hematophagous leech (Haemadipsa japonica) in Yakushima by genetic barcoding and compared the results with those for mammal composition revealed by camera trapping. We analyzed 119 samples using two sets of primers by Sanger sequencing and one set of primer by next generation sequencing. The proportion of the samples that were successfully sequenced and identified to at least one species was 11.8–24.3%, depending on the three different methods. In all of these three methods, most of the samples were identified as sika deer (18/20, 6/15 and 16/29) or human (2/20, 7/15 and 21/29). The nonhuman mammal host species composition was significantly different from that estimated by camera trapping. Sika deer was the main host, which may be related with their high abundance, large body size and terrestriality. Ten samples included DNA derived from multiple species of vertebrates. This may be due to the contamination of human DNA, but we also found DNA from deer, Japanese macaque and a frog in the same samples, suggesting the mixture of the two meals in the gut of the leech. Using H. japonica‐derived iDNA would not be suitable to make an inventory of species, but it may be useful to collect genetic information on the targeted species, due to their high host selectivity
The Met oncogene and basal-like breast cancer: another culprit to watch out for?
Recent findings suggest the involvement of the MET oncogene, encoding the tyrosine kinase receptor for hepatocyte growth factor, in the onset and progression of basal-like breast carcinoma. The expression profiles of basal-like tumors - but not those of other breast cancer subtypes - are enriched for gene sets that are coordinately over-represented in transcriptional signatures regulated by Met. Consistently, tissue microarray analyses have revealed that Met immunoreactivity is much higher in basal-like cases of human breast cancer than in other tumor types. Finally, mouse models expressing mutationally activated forms of Met develop a high incidence of mammary tumors, some of which exhibit basal characteristics. The present review summarizes current knowledge on the role and activity of Met in basal-like breast cancer, with a special emphasis on the correlation between this tumor subtype and the cellular hierarchy of the normal mammary gland
Effect of introducing a cyclobutylmethyl group into an onium cation on the thermodynamic properties of ionic clathrate hydrates
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