Smart Cardiovascular Stent against In-Stent Restenosis

Jump Starting Technologies, Patent Issues, & Translational Medicine Poster SessionA smart cardiovascular stent to be used as a single set of theranostics (therapeutics and diagnostics) is developed. The stent is aimed at delivering nitric oxide as a therapeutic agent and monitoring stent-induced restenosis. This novel approach is intended to reduce the risks stemmed from implanted stents and lowering manufacturing cost. The proposed stent will provide a non-invasive and continuous monitoring of restenosis caused by the stent. To assess the level of restenosis, pressure and blood flow will be monitored inside the blood vessel where the stent is placed. Existing techniques that employ catheters to measure pressure inside blood vessels are not suitable because they are too invasive, cannot monitor pressure for long periods of time and restrict the patient to be in a hospital setting. Our approach consists of two miniature pressure sensors and a small microchip incorporated into the stent. The pressure sensors are placed at the opposite sides of the stent. Blood flow is obtained by assessing the pressure difference at these two points. The microchip reads out the pressure sensors outputs and wirelessly transmits them to a reader outside the body. Due to size constraints and safety reasons a battery cannot be used as a power source for the microchip. Instead, power is provided from the reader via electromagnetic coupling. In order to reduce the number of components to be implanted, we are proposing to employ the stent body not only as a mechanical supporter but also as an antenna. To provide an optimal power match between the microchip and the antenna, the impedance of the stent was fully characterized. This characterization has been performed using computer simulations of five different commercially available stent designs. It was found that at the frequencies of interest (902 to 928 MHz) the impedance is highly reactive. To compensate for the reactive impedance of the antenna, a matching network was designed. A prototype microchip with different components has been designed and is currently being fabricated. Future work includes micro-assembly of a prototype stent for the collection of pressure measurements using an aortic bifurcation model. Once completed, this stent will be useful in monitoring the level of restenosis and will lower the risks presented by implantable stents

Cold Water and High Ice Cover on Great Lakes in Spring 2014

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108350/1/eost2014EO340001.pd

Towards Deconstruction of the Type D (2,0) Theory

We propose a four-dimensional supersymmetric theory that deconstructs, in a particular limit, the six-dimensional $(2,0)$ theory of type $D_k$. This 4d theory is defined by a necklace quiver with alternating gauge nodes $\mathrm{O}(2k)$ and $\mathrm{Sp}(k)$. We test this proposal by comparing the 6d half-BPS index to the Higgs branch Hilbert series of the 4d theory. In the process, we overcome several technical difficulties, such as Hilbert series calculations for non-complete intersections, and the choice of $\mathrm{O}$ versus $\mathrm{SO}$ gauge groups. Consistently, the result matches the Coulomb branch formula for the mirror theory upon reduction to 3d

Investigation of Quasi--Realistic Heterotic String Models with Reduced Higgs Spectrum

Quasi--realistic heterotic-string models in the free fermionic formulation typically contain an anomalous U(1), which gives rise to a Fayet-Iliopolous term that breaks supersymmetry at the one--loop level in string perturbation theory. Supersymmetry is restored by imposing F- and D-flatness on the vacuum. In Phys. Rev. D 78 (2008) 046009, we presented a three generation free fermionic standard-like model which did not admit stringent F- and D-flat directions, and argued that the all the moduli in the model are fixed. The particular property of the model was the reduction of the untwisted Higgs spectrum by a combination of symmetric and asymmetric boundary conditions with respect to the internal fermions associated with the compactified dimensions. In this paper we extend the analysis of free fermionic models with reduced Higgs spectrum to the cases in which the SO(10) symmetry is left unbroken, or is reduced to the flipped SU(5) subgroup. We show that all the models that we study in this paper do admit stringent flat directions. The only examples of models that do not admit stringent flat directions remain the strandard-like models of reference Phys. Rev. D 78 (2008) 046009.Comment: 38 pages, 1 figur

Constraints on chiral operators in N=2 SCFTs

Open Access, © The Authors. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution License ( CC-BY 4.0 ), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited

Spectral and localization properties of the Dirichlet wave guide with two concentric Neumann discs

Bound states of the Hamiltonian describing a quantum particle living on three dimensional straight strip of width $d$ are investigated. We impose the Neumann boundary condition on the two concentric windows of the radii $a$ and $b$ located on the opposite walls and the Dirichlet boundary condition on the remaining part of the boundary of the strip. We prove that such a system exhibits discrete eigenvalues below the essential spectrum for any $a,b>0$. When $a$ and $b$ tend to the infinity, the asymptotic of the eigenvalue is derived. A comparative analysis with the one-window case reveals that due to the additional possibility of the regulating energy spectrum the anticrossing structure builds up as a function of the inner radius with its sharpness increasing for the larger outer radius. Mathematical and physical interpretation of the obtained results is presented; namely, it is derived that the anticrossings are accompanied by the drastic changes of the wave function localization. Parallels are drawn to the other structures exhibiting similar phenomena; in particular, it is proved that, contrary to the two-dimensional geometry, at the critical Neumann radii true bound states exist.Comment: 25 pages, 7 figure

The Study of Cellular and Molecular Physiological Characteristics of Sperm in Men Living in the Aral Sea Region

BACKGROUND: Extreme environmental situation in the Aral crisis has caused a massive chemical pollution of the territory for decades with high doses of pesticides, herbicides. Discharge of industrial waste into the rivers that feed the Aral Sea has lead to the development of various pathological processes in the human body, as well as disruption of reproductive function in young men. AIM: To evaluate the performance of molecular cellular changes in the sperm of men under the influence of dust and salt aerosols in Aral Sea region.MATERIAL AND METHODS: Clinical and laboratory studies were conducted in men 5 settlements (Aralsk-city, v. Aiteke-Bi, v. Zhalagash, v. Zhusaly, v. Shieli). We have studied male ejaculate obtained after 4-5 days of abstinence, and placed it in a warm tube with a glass stopper. On the investigation proceeded ejaculate within 20-30 minutes after its preparation, during which time he was subjected to liquefaction. Isolation and quantification of ASF, RNA, DNA, and determining the fraction of histones in sperm was performed by the method of Markusheva and Savina.RESULTS: It was found that the value of ASF in the semen of men living in the zone of ecological disaster higher compared with the values of parameters in men living in the area of environmental crisis, and this trend is observed in all age groups. The study of circulating extracellular DNA and RNA in the sperm of men registered their decline with a corresponding increase of acid precursors that can be attributed to the degradation of nucleic acids under the influence of negative factors in the complex area of ecological trouble. Also, according to a study in men residing in the areas of environmental catastrophe at the age of 18-29 years, found an increased content of the H1 histone H2A lower total fraction, H3, H4 - and a sharp increase in histone H2B content - histones.CONCLUSIONS: Men living in environmentally disadvantaged areas of Kyzylorda region under the influence of dust and salt aerosols and other toxicants leads to disruption of the reproductive function in men

Complete Intersection Moduli Spaces in N=4 Gauge Theories in Three Dimensions

We study moduli spaces of a class of three dimensional N=4 gauge theories which are in one-to-one correspondence with a certain set of ordered pairs of integer partitions. It was found that these theories can be realised on brane intervals in Type IIB string theory and can therefore be described using linear quiver diagrams. Mirror symmetry was known to act on such a theory by exchanging the partitions in the corresponding ordered pair, and hence the quiver diagram of the mirror theory can be written down in a straightforward way. The infrared Coulomb branch of each theory can be studied using moment map equations for a hyperKahler quotient of the Higgs branch of the mirror theory. We focus on three infinite subclasses of these singular hyperKahler spaces which are complete intersections. The Hilbert series of these spaces are computed in order to count generators and relations, and they turn out to be related to the corresponding partitions of the theories. For each theory, we explicitly discuss the generators of such a space and relations they satisfy in detail. These relations are precisely the defining equations of the corresponding complete intersection space.Comment: 68 pages and 33 figures. Version 2: Minor corrections and citations adde

Phases of planar 5-dimensional supersymmetric Chern-Simons theory

In this paper we investigate the large-$N$ behavior of 5-dimensional $\mathcal{N}=1$ super Yang-Mills with a level $k$ Chern-Simons term and an adjoint hypermultiplet. As in three-dimensional Chern-Simons theories, one must choose an integration contour to completely define the theory. Using localization, we reduce the path integral to a matrix model with a cubic action and compute its free energy in various scenarios. In the limit of infinite Yang-Mills coupling and for particular choices of the contours, we find that the free-energy scales as $N^{5/2}$ for $U(N)$ gauge groups with large values of the Chern-Simons 't\,Hooft coupling, $\tilde\lambda\equiv N/k$. If we also set the hypermultiplet mass to zero, then this limit is a superconformal fixed point and the $N^{5/2}$ behavior parallels other fixed points which have known supergravity duals. We also demonstrate that $SU(N)$ gauge groups cannot have this $N^{5/2}$ scaling for their free-energy. At finite Yang-Mills coupling we establish the existence of a third order phase transition where the theory crosses over from the Yang-Mills phase to the Chern-Simons phase. The phase transition exists for any value of $\tilde\lambda$, although the details differ between small and large values of $\tilde\lambda$. For pure Chern-Simons theories we present evidence for a chain of phase transitions as $\tilde\lambda$ is increased. We also find the expectation values for supersymmetric circular Wilson loops in these various scenarios and show that the Chern-Simons term leads to different physical properties for fundamental and anti-fundamental Wilson loops. Different choices of the integration contours also lead to different properties for the loops.Comment: 40 pages, 17 figures, Minor corrections, Published versio