7,010 research outputs found
Discovery of TUG-770: a highly potent free fatty acid receptor 1 (FFA1/GPR40) agonist for treatment of type 2 diabetes
Free fatty acid receptor 1 (FFA1 or GPR40) enhances glucose-stimulated insulin secretion from pancreatic β-cells and currently attracts high interest as a new target for the treatment of type 2 diabetes. We here report the discovery of a highly potent FFA1 agonist with favorable physicochemical and pharmacokinetic properties. The compound efficiently normalizes glucose tolerance in diet-induced obese mice, an effect that is fully sustained after 29 days of chronic dosing
High Q Cavity Induced Fluxon Bunching in Inductively Coupled Josephson Junctions
We consider fluxon dynamics in a stack of inductively coupled long Josephson
junctions connected capacitively to a common resonant cavity at one of the
boundaries. We study, through theoretical and numerical analysis, the
possibility for the cavity to induce a transition from the energetically
favored state of spatially separated shuttling fluxons in the different
junctions to a high velocity, high energy state of identical fluxon modes.Comment: 8 pages, 5 figure
Palliative Medicines for Children â A New Frontier in Paediatric Research
Objectives: This paper seeks to highlight from a UK perspective the current lack of a research evidence base in paediatric palliative care that has resulted in a paucity of available medicines with appropriate formulations (strength and dosage form) to provide symptom management for children with life-limiting illnesses and to raise awareness of this group of âtherapeutic orphansâ. Currently, clinicians have limited, often unsuitable medication choices for their paediatric palliative care patients, with little hope of moving away from the status quo. / Key findings: Most medicines used in children receiving palliative care are old and off-patent drugs, developed for and tested in an adult population. Many are not available in suitable formulations (dosage form and strength) for administration to children and there are often no age-related profiles of adverse drug reactions or for safe dosing. / Summary: Existing regional paediatric palliative care networks and support organisations should lobby funding bodies and the academic community to support appropriate research for this group of therapeutic orphans. Support must also be provided to pharmaceutical companies in the development of suitable products with appropriate formulations
Controlling a resonant transmission across the -potential: the inverse problem
Recently, the non-zero transmission of a quantum particle through the
one-dimensional singular potential given in the form of the derivative of
Dirac's delta function, , with , being a
potential strength constant, has been discussed by several authors. The
transmission occurs at certain discrete values of forming a resonance
set . For
this potential has been shown to be a perfectly reflecting wall. However, this
resonant transmission takes place only in the case when the regularization of
the distribution is constructed in a specific way. Otherwise, the
-potential is fully non-transparent. Moreover, when the transmission
is non-zero, the structure of a resonant set depends on a regularizing sequence
that tends to in the sense of
distributions as . Therefore, from a practical point of
view, it would be interesting to have an inverse solution, i.e. for a given
to construct such a regularizing sequence
that the -potential at this value is
transparent. If such a procedure is possible, then this value
has to belong to a corresponding resonance set. The present paper is devoted to
solving this problem and, as a result, the family of regularizing sequences is
constructed by tuning adjustable parameters in the equations that provide a
resonance transmission across the -potential.Comment: 21 pages, 4 figures. Corrections to the published version added;
http://iopscience.iop.org/1751-8121/44/37/37530
Fetal growth, birth size and energetic cost of gestation in southern right whales
The cost of reproduction greatly affects a speciesâ life history strategy. Baleen whales exhibit some of the fastest offspring growth rates in the animal kingdom. We quantified the energetic cost of gestation for southern right whales (Eubalaena australis) by combining whaling catch records of pregnant females with photogrammetry data on southern right whale mothers and calves from two breeding grounds in Argentina and Australia. The relationship between calf birth size and maternal length was determined from repeated measurements of individual females before and after giving birth. Fetal growth was determined from generalized linear models fitted to fetal length data from whaling operations between 1961 and 1967. Fetal length was converted to volume and mass, using the volume-to-length relationship of newborn southern right whales calves, and published tissue composition and energy content estimates. Fetal maintenance costs (heat of gestation) and the energy content of the placenta were predicted from published relationships and added to the fetal growth cost to calculate the total cost of gestation. Our findings showed that fetal growth rates and birth size increased linearly with maternal length, with calves being born at âź35% maternal length. Fetal length increased curvilinearly through gestation, which resulted in an exponential increase in fetal volume and mass. Consequently, the cost of gestation was very low during the first (0.1% of total cost) and second trimester (4.9%), but increased rapidly during the last trimester (95.0%). The heat of gestation incurred the highest cost for pregnant females (73.8%), followed by fetal growth (21.2%) and the placental energy content (5.0%)
Large-scale 3-D modeling by integration of resistivity models and borehole data through inversion
We present an automatic method for parameterization of a 3-D model of the
subsurface, integrating lithological information from boreholes with
resistivity models through an inverse optimization, with the objective of
further detailing of geological models, or as direct input into groundwater
models. The parameter of interest is the clay fraction, expressed as the
relative length of clay units in a depth interval. The clay fraction is
obtained from lithological logs and the clay fraction from the resistivity
is obtained by establishing a simple petrophysical relationship, a
translator function, between resistivity and the clay fraction. Through
inversion we use the lithological data and the resistivity data to determine
the optimum spatially distributed translator function. Applying the
translator function we get a 3-D clay fraction model, which holds information
from the resistivity data set and the borehole data set in one variable.
Finally, we use k-means clustering to generate a 3-D model of the subsurface
structures. We apply the procedure to the Norsminde survey in Denmark,
integrating approximately 700 boreholes and more than 100 000 resistivity
models from an airborne survey in the parameterization of the 3-D model
covering 156 km2. The final five-cluster 3-D model differentiates between
clay materials and different high-resistivity materials from information held
in the resistivity model and borehole observations, respectively
Resonant enhancement of the jump rate in a double-well potential
We study the overdamped dynamics of a Brownian particle in the double-well
potential under the influence of an external periodic (AC) force with zero
mean. We obtain a dependence of the jump rate on the frequency of the external
force. The dependence shows a maximum at a certain driving frequency. We
explain the phenomenon as a switching between different time scales of the
system: interwell relaxation time (the mean residence time) and the intrawell
relaxation time. Dependence of the resonant peak on the system parameters,
namely the amplitude of the driving force A and the noise strength
(temperature) D has been explored. We observe that the effect is well
pronounced when A/D > 1 and if A/D 1 the enhancement of the jump rate can be of
the order of magnitude with respect to the Kramers rate.Comment: Published in J. Phys. A: Math. Gen. 37 (2004) 6043-6051; 6 figure
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