91 research outputs found
Higgs inflation from new K\"ahler potential
We introduce a new class of models of Higgs inflation using the
superconformal approach to supergravity by modifying the Khler
geometry. Using such a mechanism, we construct a phenomenological functional
form of a new Khler potential. From this we construct various types
of models which are characterized by a superconformal symmetry breaking
parameter , and depending on the numerical values of we classify
all of the proposed models into three categories. Models with minimal coupling
are identified by branch which are made up of shift
symmetry preserving flat directions. We also propose various other models by
introducing a non-minimal coupling of the inflaton field to gravity described
by branch. We employ all these proposed models to study
the inflationary paradigm by estimating the major cosmological observables and
confront them with recent observational data from WMAP9 along with other
complementary data sets, as well as independently with PLANCK. We also mention
an allowed range of non-minimal couplings and the {\it Yukawa} type of
couplings appearing in the proposed models used for cosmological parameter
estimation.Comment: 13 pages, 6 figures, version to appear in Nuclear Physics
Controlled Electrokinetic Particle Manipulation using Paper-and-Pencil Microfluidics
Dielectrophoresis is a very promising technique for particle manipulation on
a chip. In this study, we demonstrate a controlled mannuvering of polystryrene
particles on a simple paper-and-pencil based device by exploiting the
underlying electrokinetics with primary contribution from dielectrophoretic
(DEP) forces. On contrary to other reported DEP devices, the present
configuration does not demand a shophitcated laboratory module for creating a
non-uniform electric field, which is essential requirement in DEP settings. We
demonstrate positive dielectrophoresis (pDEP) to trap 1 um size polystyrene
particle for low-conductivity suspending medium, at an applied field strength
of 100 V/cm. In addition, the switching of the trapping direction (positive to
negative dielectrophoresis) can be simply achieved by manipulating the
conductivity of the media. We further bring out an optimum range of pH for
effective particle trapping. These results have significant implications
towards designing cell-on-a-chip based point of care diagnostic devices for
resource limited settings.Comment: 21 page
New-onset hyperglycemia: a potential clue to detect early pancreatic cancer
Pancreatic adenocarcinoma has an incidence rate nearly equal to the mortality rate and this is mostly due to late symptom onset and diagnosis. Evidence has indicated that new-onset diabetes may be a manifestation of occult pancreatic carcinoma. Authors report the case of a young female who presented with new-onset severe hyperglycemia and superficial thrombophlebitis. She was subsequently diagnosed with pancreatic cancer confirmed by histopathology. Her glycemic status evaluated 6 months prior to her presentation during institutional health check-up was entirely normal. This case report will serve to emphasize that new-onset diabetes in certain patients could be a presenting feature of pancreatic cancer.Pancreatic adenocarcinoma has an incidence rate nearly equal to the mortality rate and this is mostly due to late onset of symptoms and delay in diagnosis. Early diagnosis of this cancer gives the opportunity for total resection of pancreas and creates hope for a full recovery. Compelling evidence now indicates that new-onset diabetes may be a manifestation of occult pancreatic carcinoma. Authors report a young female who presented with new-onset severe hyperglycemia and superficial thrombophlebitis. She was subseÂquently diagnosed with pancreatic cancer confirmed by histopathology. Her glycemic status evaluated 6 months prior to her presentation during institutional health check-up was entirely normal. This case report will serve to emphasize that new-onset diabetes in certain patients could be a presenting feature of pancreatic cancer. (Clin Diabetol 2017; 6, 3: 115–117
Exploring the Gap Between Tolerant and Non-Tolerant Distribution Testing
The framework of distribution testing is currently ubiquitous in the field of property testing. In this model, the input is a probability distribution accessible via independently drawn samples from an oracle. The testing task is to distinguish a distribution that satisfies some property from a distribution that is far in some distance measure from satisfying it. The task of tolerant testing imposes a further restriction, that distributions close to satisfying the property are also accepted.
This work focuses on the connection between the sample complexities of non-tolerant testing of distributions and their tolerant testing counterparts. When limiting our scope to label-invariant (symmetric) properties of distributions, we prove that the gap is at most quadratic, ignoring poly-logarithmic factors. Conversely, the property of being the uniform distribution is indeed known to have an almost-quadratic gap.
When moving to general, not necessarily label-invariant properties, the situation is more complicated, and we show some partial results. We show that if a property requires the distributions to be non-concentrated, that is, the probability mass of the distribution is sufficiently spread out, then it cannot be non-tolerantly tested with o(?n) many samples, where n denotes the universe size. Clearly, this implies at most a quadratic gap, because a distribution can be learned (and hence tolerantly tested against any property) using ?(n) many samples. Being non-concentrated is a strong requirement on properties, as we also prove a close to linear lower bound against their tolerant tests.
Apart from the case where the distribution is non-concentrated, we also show if an input distribution is very concentrated, in the sense that it is mostly supported on a subset of size s of the universe, then it can be learned using only ?(s) many samples. The learning procedure adapts to the input, and works without knowing s in advance
Engulfment pathways promote programmed cell death by enhancing the unequal segregation of apoptotic potential
Components of the conserved engulfment pathways promote programmed cell death in Caenorhabditis elegans (C. elegans) through an unknown mechanism. Here we report that the phagocytic receptor CED-1 mEGF10 is required for the formation of a dorsal-ventral gradient of CED-3 caspase activity within the mother of a cell programmed to die and an increase in the level of CED-3 protein within its dying daughter. Furthermore, CED-1 becomes enriched on plasma membrane regions of neighbouring cells that appose the dorsal side of the mother, which later forms the dying daughter. Therefore, we propose that components of the engulfment pathways promote programmed cell death by enhancing the polar localization of apoptotic factors in mothers of cells programmed to die and the unequal segregation of apoptotic potential into dying and surviving daughters. Our findings reveal a novel function of the engulfment pathways and provide a better understanding of how apoptosis is initiated during C. elegans development
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