466 research outputs found
Deformation theory of deformed Hermitian Yang-Mills connections and deformed Donaldson-Thomas connections
A deformed Hermitian Yang-Mills (dHYM) connection and a deformed
Donaldson-Thomas (dDT) connection are Hermitian connections on a Hermitian
vector bundle over a K\"ahler manifold and a -manifold, which are
believed to correspond to a special Lagrangian and a (co)associative cycle via
mirror symmetry, respectively. In this paper, when is a line bundle,
introducing a new balanced Hermitian structure from the initial Hermitian
structure and a dHYM connection and a new coclosed -structure from the
initial -structure and a dDT connection, we show that their deformations
are controlled by a subcomplex of the canonical complex introduced by Reyes
Carri\'on. The expected dimension is given by the first Betti number of a base
manifold for both cases. In the case of dHYM connections, we show that there
are no obstructions for their deformations, and hence, the moduli space is
always a smooth manifold. As an application of this, we give another proof of
the triviality of the deformations of dHYM metrics proved by Jacob and Yau. In
the case of dDT connections, we show that the moduli space is smooth if we
perturb the initial -structure generically.Comment: 56 pages, 1 figure, 4 tables, v2: a few typos are corrected, a
reference is adde
A Dilated Odontoma in the Second Molar Region of the Mandible
A case of dilated odontoma in the second molar region of the mandible was reported. The patient was a 14-year-old female. Panoramic X-ray and CT examination revealed an oval ring-shaped radiopaque lesion accompanying a radiolucent area in the center at the left second molar region of the mandible. The left second molar and all third molars were not found. The lesion was diagnosed as odontoma and extirpated under general anesthesia. The lesion was a spherical mass of 12x9mm. Histologically, the mass was composed of dentin arranged in an oval ring shape with dentinal tubules. Inside the dentin, immature enamel was present. The central area of the mass was filled with fibrous tissue with a small nest of bone and cementum. Bone tissue was also observed in contact with the immature enamel layer. These morphological and histological features are compatible with those of a dilated odontoma
A Case of Dominant Dystrophic Epidermolysis Bullosa with a G2043R Mutation in the Type VII Collagen Gene
Dystrophic epidermolysis bullosa (DEB) is a subepidermal
bulla, characterized by severe itching, lichenoid
or nodular prurigo-like lesions, skin erosion,
scars, milia, and nail dystrophy, resulting from COL7A1
mutation. Herein, we report a case of dominant DEB
with a G2043R mutation in COL7A1
A Lagrangian construction of rotating stars
We present a new formulation for numerically obtaining axisymmetric
equilibrium structures of rotating stars in two spatial dimensions. With a view
to apply it to the secular evolution of rotating stars, we base it on the
Lagrangian description, i.e., we solve the force-balance equations to find the
spatial positions of fluid elements endowed individually with a mass, specific
entropy and angular momentum. The system of nonlinear equations obtained by
finite-differencing the basic equations are solved with the W4 method, which is
a new multi-dimensional root-finding scheme of our own devising. We augment it
with a remapping scheme to avoid distortions of the Lagrangian coordinates. In
this first one of a series of papers, we will give a detailed description of
these methods initially. We then present the results of some test calculations,
which include the construction of both rapidly rotating barotropic and
baroclinic equilibrium states. We gauge their accuracies quantitatively with
some diagnostic quantities as well as via comparisons with the counterparts
obtained with an Eulerian code. For a demonstrative purpose, we apply the code
to a toy-model cooling calculation of a rotating white dwarf.Comment: 15pages, 14 figures, submitted to MNRA
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