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West Bend, WI, United States

Whitlow P.L.,Cleveland Clinic | Feldman T.,University of Chicago | Pedersen W.R.,Minneapolis Heart Institute and Foundation | Lim D.S.,University of Virginia | And 14 more authors.
Journal of the American College of Cardiology | Year: 2012

Objectives: The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study (HRS) assessed the safety and effectiveness of the MitraClip device (Abbott Vascular, Santa Clara, California) in patients with significant mitral regurgitation (MR) at high risk of surgical mortality rate. Background: Patients with severe MR (3 to 4+) at high risk of surgery may benefit from percutaneous mitral leaflet repair, a potentially safer approach to reduce MR. Methods: Patients with severe symptomatic MR and an estimated surgical mortality rate of ≥12% were enrolled. A comparator group of patients screened concurrently but not enrolled were identified retrospectively and consented to compare survival in patients treated by standard care. Results: Seventy-eight patients underwent the MitraClip procedure. Their mean age was 77 years, >50% had previous cardiac surgery, and 46 had functional MR and 32 degenerative MR. MitraClip devices were successfully placed in 96% of patients. Protocol-predicted surgical mortality rate in the HRS and concurrent comparator group was 18.2% and 17.4%, respectively, and Society of Thoracic Surgeons calculator estimated mortality rate was 14.2% and 14.9%, respectively. The 30-day procedure-related mortality rate was 7.7% in the HRS and 8.3% in the comparator group (p = NS). The 12-month survival rate was 76% in the HRS and 55% in the concurrent comparator group (p = 0.047). In surviving patients with matched baseline and 12-month data, 78% had an MR grade of ≤2+. Left ventricular end-diastolic volume improved from 172 ml to 140 ml and end-systolic volume improved from 82 ml to 73 ml (both p = 0.001). New York Heart Association functional class improved from III/IV at baseline in 89% to class I/II in 74% (p < 0.0001). Quality of life was improved (Short Form-36 physical component score increased from 32.1 to 36.1 [p = 0.014] and the mental component score from 45.5 to 48.7 [p = 0.065]) at 12 months. The annual rate of hospitalization for congestive heart failure in surviving patients with matched data decreased from 0.59 to 0.32 (p = 0.034). Conclusions: The MitraClip device reduced MR in a majority of patients deemed at high risk of surgery, resulting in improvement in clinical symptoms and significant left ventricular reverse remodeling over 12 months. (Pivotal Study of a Percutaneous Mitral Valve Repair System [EVEREST II]; NCT00209274). © 2012 by the American College of Cardiology Foundation. Source

Sebree J.A.,Purdue University | Sebree J.A.,NASA | Kidwell N.M.,Purdue University | Selby T.M.,West Bend | And 3 more authors.
Journal of the American Chemical Society | Year: 2012

Conformer-specific, vibrationally resolved electronic spectroscopy of benzylallene (4-phenyl-1,2-butadiene) is presented along with a detailed analysis of the products formed via its ultraviolet photoexcitation. Benzylallene is the minor product of the recombination of benzyl and propargyl radicals. The mass-selective resonant two-photon ionization spectrum of benzylallene was recorded under jet-cooled conditions, with its S 0-S 1 origin at 37 483 cm -1. UV-UV holeburning spectroscopy was used to show that only one conformer was present in the expansion. Rotational band contour analysis provided rotational constants and transition dipole moment direction consistent with a conformation in which the allene side chain is in the anti position, pointing away from the phenyl ring. The photochemistry of benzylallene was studied in a pump-probe geometry in which photoexcitation occurred by counter-propagating the expansion with a photoexcitation laser. The laser was timed to interact with the gas pulse in a short tube that extended the collisional region of the expansion. The products were cooled during expansion of the gas mixture into vacuum, before being interrogated using mass-selective resonant two-photon ionization. The UV-vis spectra of the photochemical products were compared to literature spectra for identification. Several wavelengths were chosen for photoexcitation, ranging from the S 0-S 1 origin transition (266.79 nm) to 193 nm. Comparison of the product spectral intensities as a function of photoexcitation wavelength provides information on the wavelength dependence of the product yields. Photoexcitation at 266.79 nm yielded five products (benzyl radical, benzylallenyl radical, 1-phenyl-1,3-butadiene, 1,2-dihydronaphthalene, and naphthalene), with naphthalene and benzylallenyl radicals dominant. At 193 nm, the benzylallenyl radical signal was greatly reduced in intensity, while three additional C 10H 8 isomeric products were observed. An extensive set of calculations of key stationary points on the ground state C 10H 10 and C 10H 9 potential energy surfaces were carried out at the DFT B3LYP/6-311G(d,p) level of theory. Mechanisms for formation of the observed products are proposed based on these potential energy surfaces, constrained by the results of cursory studies of the photochemistry of 1-phenyl-1,3-butadiene and 4-phenyl-1-butyne. A role for tunneling on the excited state surface in the formation of naphthalene is suggested by studies of partially deuterated benzylallene, which blocked naphthalene formation. © 2011 American Chemical Society. Source

Shah A.G.,Weizmann Institute of Science | Shah A.G.,University of Wisconsin - Milwaukee | Friedman J.L.,University of Wisconsin - Milwaukee | Keidl T.S.,West Bend
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

This is the first of two papers on computing the self-force in a radiation gauge for a particle of mass m moving in circular, equatorial orbit about a Kerr black hole. In the extreme-mass-ratio inspiral (EMRI) framework, with mode-sum renormalization, we compute the renormalized value of the quantity H12h αβuαuβ, gauge-invariant under gauge transformations generated by a helically symmetric gauge vector; here, h αβ is the metric perturbation, uα the particle's 4-velocity. We find the related order m correction to the particle's angular velocity at fixed renormalized redshift (and to its redshift at fixed angular velocity), each of which can be written in terms of H. The radiative part of the metric perturbation is constructed from a Hertz potential that is extracted from the Weyl scalar by an algebraic inversion T.S. Keidl, Phys. Rev. D 82, 124012 (2010). We then write the spin-weighted spheroidal harmonics as a sum over spin-weighted spherical harmonics Yms and use mode-sum renormalization to find the renormalization coefficients by matching a series in L=+1/2 to the large-L behavior of the expression for H. The nonradiative parts of the perturbed metric associated with changes in mass and angular momentum are calculated in the Kerr gauge. © 2012 American Physical Society. Source

Sutter P.,West Bend
Chemical Engineering Progress | Year: 2010

Direct steam injection (DSI) is a viable alternative to indirect heating for many applications that use process steam, require large volumes of hot water, or need accurate temperature control. The most sophisticated DSI water heating systems are so compact that they can be suspended from a wall or ceiling or mounted on a compact skid on the floor. The more-sophisticated DSI systems provide very close temperature control at both constant and variable flowrates and in applications that involve frequent stopping and starting. The control is possible because heat transfers immediately from the steam to the liquid when heating starts. A DSI system that is properly sized for the available steam supply, cold water supply, and hot water demand, can continuously deliver hot water as required. The simplest DSI system is the steam sparger, which is a perforated pipe or other fixture through which steam is bubbled directly into the water in a vented storage tank. Source

Keidl T.S.,West Bend | Shah A.G.,University of Wisconsin - Milwaukee | Friedman J.L.,University of Wisconsin - Milwaukee | Kim D.-H.,Max Planck Institute Fr Gravitationsphysik | And 3 more authors.
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

In this, the first of two companion papers, we present a method for finding the gravitational self-force in a modified radiation gauge for a particle moving on a geodesic in a Schwarzschild or Kerr spacetime. An extension of an earlier result by Wald is used to show the spin weight ±2 perturbed Weyl scalar (ψ0 or ψ4) determines the metric perturbation outside the particle up to a gauge transformation and an infinitesimal change in mass and angular momentum. A Hertz potential is used to construct the part of the retarded metric perturbation that involves no change in mass or angular momentum from ψ0 in a radiation gauge. The metric perturbation is completed by adding changes in the mass and angular momentum of the background spacetime outside the radial coordinate r0 of the particle in any convenient gauge. The resulting metric perturbation is singular only on the trajectory of the particle. A mode-sum method is then used to renormalize the self-force. Gralla shows that the renormalized self-force can be used to find the correction to a geodesic orbit in a gauge for which the leading, O(ρ⊃-1), term in the metric perturbation has spatial components even under a parity transformation orthogonal to the particle trajectory, and we verify that the metric perturbation in a radiation gauge satisfies that condition. We show that the singular behavior of the metric perturbation and the expression for the bare self-force have the same power-law behavior in L=ℓ+1/2 as in a Lorenz gauge (with different coefficients). We explicitly compute the singular Weyl scalar and its mode-sum decomposition to subleading order in L for a particle in circular orbit in a Schwarzschild geometry and obtain the renormalized field. Because the singular field can be defined as this mode sum, the coefficients of each angular harmonic in the sum must agree with the large L limit of the corresponding coefficients of the retarded field. One may therefore compute the singular field by numerically matching the retarded field to a power series in L. To check the accuracy of the numerical method, we analytically compute leading and subleading terms in the singular expansion of ψ0 and compare the numerical and analytic values of the renormalization constants, finding agreement to high precision. Details of the numerical computation of the perturbed metric, the self-force, and the quantity hαβuαuβ (gauge invariant under helically symmetric gauge transformations) are presented for this test case in the companion paper. © 2010 The American Physical Society. Source

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