4,140 research outputs found
Triune Synergy in Biomedical Research: Uniting Pharmaceutical Companies, University Researchers, and the NIH through the Drug Repurposing Project at NCATS
The drug discovery process is long, expensive, and prone to failure. The average cost of developing an approved drug is increasing exponentially. Exacerbating the problem is the fact that, instead of being translated into medical therapies, basic scientific discoveries are languishing without further development. This phenomenon, known as the “Valley of Death,” has become a concern of the National Institutes of Health (NIH), which is the main funder of biomedical research in the United States. In an attempt to build bridges across the Valley of Death, the NIH created the National Center for Advancing Translational Sciences (NCATS) in December 2011. NCATS’ first project was the Discovering New Therapeutic
Uses for Existing Molecules Program (the “Repurposing Project”).
The linchpin for getting the Repurposing Project off the ground was convincing the pharmaceutical companies to allow outside researchers to experiment with their patented drugs. If an outside researcher were to be successful in finding a new use for the drug, the company’s intellectual property (IP) ownership over the drug would be diluted. This, in turn, would limit the company’s ability to profit from the drug. In a break from their normally secretive business practices, the eight participating pharmaceutical companies published Collaborative Research Agreements (CRAs) on the NIH’s website that outline the intellectual property rights they were willing to give up in order to participate in the project.
This Note discusses the content of the CRAs developed for the Repurposing Project, examines the IP provisions that each of the eight participating companies incorporated into its CRA, and argues that the Repurposing Project aligns the skills and interests of three of the most important entities in biomedical research, thereby promoting a triune synergy unique to the biomedical research field
Oblique propagation of arbitrary amplitude electron acoustic solitary waves in magnetized kappa-distributed plasmas
The linear and nonlinear properties of large amplitude electron-acoustic
waves are investigated in a magnetized plasma comprising two distinct electron
populations (hot and cold) and immobile ions. The hot electrons are assumed to
be in a non-Maxwellian state, characterized by an excess of superthermal
particles, here modelled by a kappa-type long-tailed distribution function.
Waves are assumed to propagate obliquely to the ambient magnetic field. Two
types of electrostatic modes are shown to exist in the linear regime, and their
properties are briefly analyzed. A nonlinear pseudopotential type analysis
reveals the existence of large amplitude electrostatic solitary waves and
allows for an investigation of their propagation characteristics and existence
domain, in terms of the soliton speed (Mach number). The effects of the key
plasma configuration parameters, namely, the superthermality index and the cold
electron density, on the soliton characteristics and existence domain, are
studied. The role of obliqueness and magnetic field are discussed.Comment: Submitted to Plasma Physics and Controlled Fusio
New Seiberg Dualities from N=2 Dualities
We propose a number of new Seiberg dualities of N=1 quiver gauge theories.
The new Seiberg dualities originate in new S-dualities of N=2 superconformal
field theories recently proposed by Gaiotto. N=2 S-dual theories deformed by
suitable mass terms flow to our N=1 Seiberg dual theories. We show that the
number of exactly marginal operators is universal for these Seiberg dual
theories and the 't Hooft anomaly matching holds for these theories. These
provide strong evidence for the new Seiberg dualities. Furthermore, we study in
detail the Klebanov-Witten type theory and its dual as a concrete example. We
show that chiral operators and their non-linear relations match between these
theories. These arguments also give non-trivial consistency checks for our
proposal.Comment: 31 pages, 7 figures. v2:version to appear in JHE
Targeting cellular calcium homeostasis to prevent cytokine-mediated beta cell death
AbstractPro-inflammatory cytokines are important mediators of islet inflammation, leading to beta cell death in type 1 diabetes. Although alterations in both endoplasmic reticulum (ER) and cytosolic free calcium levels are known to play a role in cytokine-mediated beta cell death, there are currently no treatments targeting cellular calcium homeostasis to combat type 1 diabetes. Here we show that modulation of cellular calcium homeostasis can mitigate cytokine- and ER stress-mediated beta cell death. The calcium modulating compounds, dantrolene and sitagliptin, both prevent cytokine and ER stress-induced activation of the pro-apoptotic calcium-dependent enzyme, calpain, and partly suppress beta cell death in INS1E cells and human primary islets. These agents are also able to restore cytokine-mediated suppression of functional ER calcium release. In addition, sitagliptin preserves function of the ER calcium pump, sarco-endoplasmic reticulum Ca2+-ATPase (SERCA), and decreases levels of the pro-apoptotic protein thioredoxin-interacting protein (TXNIP). Supporting the role of TXNIP in cytokine-mediated cell death, knock down of TXNIP in INS1-E cells prevents cytokine-mediated beta cell death. Our findings demonstrate that modulation of dynamic cellular calcium homeostasis and TXNIP suppression present viable pharmacologic targets to prevent cytokine-mediated beta cell loss in diabetes.</jats:p
Stop-and-go kinetics in amyloid fibrillation
Many human diseases are associated with protein aggregation and fibrillation. Using glucagon as a model system for protein fibrillation we show that fibrils grow in an intermittent fashion, with periods of growth followed by long pauses. Remarkably, even if the intrinsic transition rates vary considerably in each experiment, the probability of being in the growing (stopping) state is very close to 1/4 (3/4), suggesting the presence of 4 independent conformations of the fibril tip. We discuss this possibility in terms of existing structural knowledge
Space-time evolution of bulk QCD matter
We introduce a combined fully three-dimensional macroscopic/microscopic
transport approach employing relativistic 3D-hydrodynamics for the early,
dense, deconfined stage of the reaction and a microscopic non-equilibrium model
for the later hadronic stage where the equilibrium assumptions are not valid
anymore. Within this approach we study the dynamics of hot, bulk QCD matter,
which is being created in ultra-relativistic heavy ion collisions at RHIC. Our
approach is capable of self-consistently calculating the freezeout of the
hadronic system, while accounting for the collective flow on the hadronization
hypersurface generated by the QGP expansion. In particular, we perform a
detailed analysis of the reaction dynamics, hadronic freezeout, and transverse
flow.Comment: 24 pages, 27 figure
Discovery of New Dwarf Galaxy near The Isolated Spiral Galaxy NGC 6503
We report the discovery of a new dwarf galaxy (NGC6503-d1) during the Subaru
extended ultraviolet (XUV) disk survey. It is a likely companion of the spiral
galaxy NGC6503. The resolved images, in B, V, R, i, and Halpha, show an
irregular appearance due to bright stars with underlying, smooth and unresolved
stellar emission. It is classified as the transition type (dIrr/dSph). Its
structural properties are similar to those of the dwarfs in the Local Group,
with a V absolute magnitude ~ -10.5, half-light radius ~400 pc, and central
surface brightness ~25.2. Despite the low stellar surface brightness
environment, one HII region was detected, though its Halpha luminosity is low,
indicating an absence of any appreciable O-stars at the current epoch. The
presence of multiple stellar populations is indicated by the color-magnitude
diagram of ~300 bright resolved stars and the total colors of the dwarf, with
the majority of its total stellar mass ~4x10^6 Msun in an old stellar
population.Comment: Published in ApJL (ApJ, 802, L24). 7 pages, 4 figure
The Universal Initial Mass Function In The XUV Disk of M83
We report deep Subaru Halpha observations of the XUV disk of M83. These new
observations enable the first complete census of very young stellar clusters
over the entire XUV disk. Combining Subaru and GALEX data with a stellar
population synthesis model, we find that (1) the standard, but
stochastically-sampled, initial mass function (IMF) is preferred over the
truncated IMF, because there are low mass stellar clusters (10^{2-3}Msun) that
host massive O-type stars; that (2) the standard Salpeter IMF and a simple
aging effect explain the counts of FUV-bright and Halpha-bright clusters with
masses >10^3Msun; and that (3) the Halpha to FUV flux ratio over the XUV disk
supports the standard IMF. The Subaru Prime Focus Camera (Suprime-Cam) covers a
large area even outside the XUV disk -- far beyond the detection limit of the
HI gas. This enables us to statistically separate the stellar clusters in the
disk from background contamination. The new data, model, and previous
spectroscopic studies provide overall consistent results with respect to the
internal dust extinction (Av~0.1 mag) and low metallicity (~0.2Zsun) using the
dust extinction curve of SMC.Comment: 11 pages, 8 figures. Accepted for publication in Ap
Subaru Deep Survey VI. A Census of Lyman Break Galaxies at z=4 and 5 in the Subaru Deep Fields: Clustering Properties
We investigate the clustering properties of 2,600 Lyman Break Galaxies (LBGs)
at z=3.5-5.2 in two large blank fields, the Subaru Deep Field and the
Subaru/XMM Deep Field (600arcmin^2 each). The angular correlation functions of
these LBGs show a clear clustering at both z~4 and 5. The correlation lengths
are r_0= 4.1^{+0.2}_{-0.2} and 5.9^{+1.3}_{-1.7} h_{100}^{-1} Mpc (r_0=
5.1^{+1.0}_{-1.1} and 5.9^{+1.3}_{-1.7} h_{100}^{-1} Mpc) for all the detected
LBGs (for L>L* LBGs) at z~4 and 5, respectively. These correlation lengths
correspond to galaxy-dark matter biases of b_g= 2.9^{+0.1}_{-0.1} and
4.6^{+0.9}_{-1.2} (b_g=3.5^{+0.6}_{-0.7} and 4.6^{+0.9}_{-1.2}), for all the
detected LBGs (for L>L^* LBGs) at z~4 and 5, respectively. These results,
combined with estimates for z~3 LBGs in the literature, show that the
correlation length of L>L^* LBGs is almost constant, ~5 h_{100}^{-1} Mpc, over
z~3-5, while the bias monotonically increases with redshift at z>3. We also
find that for LBGs at z~4 the clustering amplitude increases with UV-continuum
luminosity and with the amount of dust extinction. We estimate the mass of dark
halos hosting various kinds of high-z galaxies including LBGs with the analytic
model given by Sheth & Tormen (1999). We find that the typical mass of dark
halos hosting L>L^* LBGs is about 1x10^{12} h_{70}^{-1}Msol over z~3-5, which
is comparable to that of the Milky Way Galaxy. A single dark halo with ~10^{12}
h_{70}^{-1} Msol is found to host 0.1-0.3 LBG on average but host about four
K-band selected galaxies.Comment: 33 pages, 12 figures, ApJ in press. Paper with high resolution
figures is available at
http://hikari.astron.s.u-tokyo.ac.jp/~ouchi/work/astroph/SDS_V_VI/SDS_VI.pdf
(PDF) (The abstract was reduced by the revision.
The Halpha Luminosity Function of the Galaxy Cluster Abell 521 at z = 0.25
We present an optical multicolor-imaging study of the galaxy cluster Abell
521 at , using Suprime-Cam on the Subaru Telescope, covering an area
of arcmin ( Mpc at ). Our imaging data taken with both a narrow-band filter,
(\AA and \AA), and broad-band filters,
, and allow us to find 165 H
emitters. We obtain the H luminosity function (LF) for the cluster
galaxies within 2 Mpc; the Schechter parameters are ,
Mpc, and erg s. Although the faint end slope, , is consistent with
that of the local cluster H LFs, the characteristic luminosity,
, is about 6 times (or mag) brighter. This strong
evolution implies that Abell 521 contains more active star-forming galaxies
than the local clusters, being consistent with the observed Butcher-Oemler
effect. However, the bright of Abell 521 may be, at least in part,
due to the dynamical condition of this cluster.Comment: 21 pages, 7 figures, ApJ, Part 1, in pres
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