2,015 research outputs found
Scaling of heat transfer augmentation due to mechanical distortions in hypervelocity boundary layers
Expression of Cadherin-11 during Organogenesis in the Chick Embryo
Cadherin-11 (cad-11) is primarily a mesenchymal cadherin that appears in delaminating neural crest cells. Its expression correlates with morphogenetic events and the pattern has been studied in mouse, rat and Xenopus embryos, but not during avian organogenesis. Our purpose was to investigate this pattern in the chick embryo during organogenesis using immunolocalization and in situ hybridization. Cad-11 was expressed in mesenchyme around the pharynx and aortic arches, eyes, auditory vesicles, lung buds, stomach, and nasal placodes. Neural expression included some cranial ganglia and also new neuroepithelium within the tail bud region undergoing secondary neurulation. We also found expression in epithelia of the developing circulatory and digestive organs. The limb buds, pineal rudiment and mesonephros were also positive. Cad-11 expression became more widespread with development. Our findings support the role of cad-11 as a mesenchymal cadherin, but provide evidence for a wider role that includes epithelial morphogenesis and secondary neurulation
A variational principle for stationary, axisymmetric solutions of Einstein's equations
Stationary, axisymmetric, vacuum, solutions of Einstein's equations are
obtained as critical points of the total mass among all axisymmetric and
symmetric initial data with fixed angular momentum. In this
variational principle the mass is written as a positive definite integral over
a spacelike hypersurface. It is also proved that if absolute minimum exists
then it is equal to the absolute minimum of the mass among all maximal,
axisymmetric, vacuum, initial data with fixed angular momentum. Arguments are
given to support the conjecture that this minimum exists and is the extreme
Kerr initial data.Comment: 21 page
Volume preserving multidimensional integrable systems and Nambu--Poisson geometry
In this paper we study generalized classes of volume preserving
multidimensional integrable systems via Nambu--Poisson mechanics. These
integrable systems belong to the same class of dispersionless KP type equation.
Hence they bear a close resemblance to the self dual Einstein equation. All
these dispersionless KP and dToda type equations can be studied via twistor
geometry, by using the method of Gindikin's pencil of two forms. Following this
approach we study the twistor construction of our volume preserving systems
Area-charge inequality for black holes
The inequality between area and charge for dynamical black
holes is proved. No symmetry assumption is made and charged matter fields are
included. Extensions of this inequality are also proved for regions in the
spacetime which are not necessarily black hole boundaries.Comment: 21 pages, 2 figure
ALMA 1.3 Millimeter Map of the HD 95086 System
Planets and minor bodies such as asteroids, Kuiper-belt objects and comets
are integral components of a planetary system. Interactions among them leave
clues about the formation process of a planetary system. The signature of such
interactions is most prominent through observations of its debris disk at
millimeter wavelengths where emission is dominated by the population of large
grains that stay close to their parent bodies. Here we present ALMA 1.3 mm
observations of HD 95086, a young early-type star that hosts a directly imaged
giant planet b and a massive debris disk with both asteroid- and Kuiper-belt
analogs. The location of the Kuiper-belt analog is resolved for the first time.
The system can be depicted as a broad (0.84), inclined
(30\arcdeg3\arcdeg) ring with millimeter emission peaked at 2006 au
from the star. The 1.3 mm disk emission is consistent with a broad disk with
sharp boundaries from 1066 to 32020 au with a surface density
distribution described by a power law with an index of --0.50.2. Our deep
ALMA map also reveals a bright source located near the edge of the ring, whose
brightness at 1.3 mm and potential spectral energy distribution are consistent
with it being a luminous star-forming galaxy at high redshift. We set
constraints on the orbital properties of planet b assuming co-planarity with
the observed disk.Comment: accepted for publication in A
NCI-MATCH Arms N & P: Phase II study of PI3K beta inhibitor GSK2636771 in patients (pts) with cancers (ca) with PTEN mutation/deletion (mut/del) or PTEN protein loss
Background: The NCI-MATCH trial is the largest national study (1173 sites) for ptswith relapsed/ refractory solid tumors, lymphomas and myeloma, which assigns tar-geted therapies based on individual tumor molecular alterations detected using theadapted Oncomine AmpliSeq panel (143 genes) and immunohistochemistry (IHC).We hypothesized that patients with PTEN-deficient cancers enrolled to Arms N and Pmay benefit from treatment with the PI3K beta-selective inhibitor GSK2636771.
Methods: Eligibility: relapsed/refractory ca, good end-organ function, and ECOG PS ≤ 1. Pts were screened for molecular alterations by centralized testing on fresh tumor biopsy and had deleterious PTEN mut/del without loss of expression (Arm N) or complete loss of cytoplasmic and nuclear PTEN staining on IHC (Arm P), and no other aberrations activating the PI3K/MTOR and MAPK pathways (mut in PIK3CA, PIK3R1, BRAF, KRAS, AKT1, TSC1/2, mTOR, RHEB, NF2, NRAS, HRAS). Pts received GSK2636771 400mg/day (28-days cycles). RECIST 1.1 overall response rate (ORR) was the primary endpoint.
Results: Of 59 enrolled pts, 56 were eligible and received treatment. Of 22 pts with PTEN mut/del (Arm N: 6 uterine, 2 breast, 2 prostate, 2 head/neck ca, 10 other), all are off treatment as of analysis (14 disease progression, 4 for adverse events [AEs], 4 other). One pt (4.5%) with prostate ca (PTEN deletion, MPRSS2-ERG fusion) attained a partial response (-42%). Of 7 (32%) pts with stable disease (SD), 2 had SD \u3e 6 months (uterine leiomyosarcoma; endometrial carcinoma). Of 34 pts with loss of PTEN protein by IHC (Arm P: 7 prostate, 6 breast, 3 squamous anal ca, 2 cholangiocarcinoma, 16 other), all are off treatment as of analysis (26 disease progression, 4 for AE, 4 other). Of 9 (37.5%) pts with SD, 3 had SD \u3e 6 months (prostate cancer; squamous bladder cancer, squamous anal cancer). Median progression-free survival was 1.8 months for both arms. Gr ≥ 3 treatment-related (tr) reversible toxicities were experienced by 30% (7) and 20% (7) of pts in arms N and P, respectively. No tr Gr 5 toxicities were observed in either arm.
Conclusions: Single agent GSK2636771 has very modest activity in ca with PTEN gene mutation/deletion and/or PTEN protein loss
Hypercomplex Integrable Systems
In this paper we study hypercomplex manifolds in four dimensions. Rather than
using an approach based on differential forms, we develop a dual approach using
vector fields. The condition on these vector fields may then be interpreted as
Lax equations, exhibiting the integrability properties of such manifolds. A
number of different field equations for such hypercomplex manifolds are
derived, one of which is in Cauchy-Kovaleskaya form which enables a formal
general solution to be given. Various other properties of the field equations
and their solutions are studied, such as their symmetry properties and the
associated hierarchy of conservation laws.Comment: Latex file, 19 page
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