Modification of vascular responses in xenotransplantation: inflammation and apoptosis

We report a case of progressive dementia and prolonged gait disturbance correlated with influenza A/H3N2 infection in 91-year-old female patient, admitted because of in ability to take care of herself due to aging and cerebral infarction. At admission, conversation and comprehension were not significantly impaired, and she was able to walk by herself. Flu symptoms such as high grade fever, chills, arthralgia, and cough appeared after a short stay at home. Influenza A/ H3N2 was confirmed serologically. Delirium occurred on the sixth day after influenza onset, persisted for three weeks, followed by recovery. Dementia symptoms such as memory defects and disorientation continued and did not improve. Due to this febrile episode, she was unable to walk unassisted. The results of computed tomography performed before and after the influenza episode were unremarkable for additional cellebro-vascular events during the observed period. Influenza infection may be an important risk factor for reducing the quality of life in the elderly. In geriatric cases, influenza should not be treated as a mere transient illness, but rather one which has important consequences for the elderly population, including the possibility of life threatening complications.     

Splitting a Delaunay Triangulation in Linear Time

Abstract. Computing the Delaunay triangulation of n points requires usually a minimum of Ω(n log n) operations, but in some special cases where some additional knowledge is provided, faster algorithms can be designed. Given two sets of points, we prove that, if the Delaunay triangulation of all the points is known, the Delaunay triangulation of each set can be computed in randomized expected linear time.     

Fourier-based maximum entropy method in stochastic dynamics

As the recent research by Tr

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bicki and Sobczyk has demonstrated the principle of maximum entropy is a powerful tool for solving stochastic differential equations. In particular, its use in connection with the moment equations generated by the Ito formula provides accurate estimations of the probability density evolution of some oscillators for which conventional methods such as the diverse closure schemes are not applicable. A major computational requirement of the method, however, lies in the need of calculating a large number of multidimensional integrals at each time step--a numerical task for which both accurate and economic algorithms are required. In this paper it is shown that conventional economic integration techniques often lead to numerical collapse of the solution, especially when dealing with highly nonlinear oscillators. A strategy that overcomes this difficulty is proposed. In essence, the integrals are reformulated in terms of multidimensional Fourier transforms, which are solved by an ad hoc FFT algorithm aimed at obtaining only one single “frequency” point. It is demonstrated that the numerical stability and the accuracy of the proposed algorithm are superior to those afforded by other integration schemes.     

Polarisation effects on the nonlinear optical characteristics of a 1.55 μm vertical-cavity semiconductor optical amplifier

The effect of polarisation on the nonlinear optical properties of a 1550 nm vertical- cavity semiconductor optical amplifier (VCSOA) subjected to external optical injection into the two orthogonal polarisations of the fundamental mode has been studied experimentally. Clockwise nonlinear switching with very high on-off contrast ratio between the output states, exceeding 50:1, is reported. It is also shown that the use of polarised light gives a reduction to only some tens of microwatts of the input power requirements needed for clockwise nonlinear switching with high on-off contrast ratio. This represents at least one order of magnitude decrease in comparison with previously reported results either in VCSOAs or in edge-emitting devices. These results offer promise for the potential use of VCSOAs for all-optical signal processing as well as for optical interconnects and all-optical switching/routing applications.     

Modelling and simulation of dispersed phase formation in steels

Modelling has proven to be an efficient way of cutting time and costs associated with the investigation of materials properties. Two examples of thermodynamic modelling are presented which describe different phenomena in steels: the precipitation of carbonitrides and Ti-based inclusions in IF steels, and the coarsening of dispersed phases in HSLA steels. The underlying mode of describing the phases is the Calphad method, which has been combined with diffusion calculations to give results from both microscopic and macroscopic statistical points of view. The results of the calculations show a good agreement with the experimental data available in literature, and the methodology may be considered as illustrative and extendible to a variety of similar cases.     

Polarimetric Detection of Targets in Heavy Inhomogeneous Clutter

Polarization diversity has proved to be a useful tool for radar detection, especially when discrimination by Doppler effect is not possible. In this paper, we address the problem of improving the performance of polarimetric detectors for targets in heavy inhomogeneous clutter. First, we introduce a new polarimetric radar model that includes the realistic dependence of the clutter reflections on the transmitted signal. Then, we develop a polarimetric detection test that is robust to inhomogeneous clutter. We run this polarimetric test against synthetic and real data to assess its performance in comparison with existing polarimetric detectors. Finally, we propose a polarimetric waveform-design algorithm to further improve the target-detection performance. A numerical analysis is presented to demonstrate the potential performance improvement that can be achieved with this algorithm.     

Fe2O3-doped forsterite ceramics as a joining partner for ZrO2 in a laser brazing process

Gastight, high-temperature stable sealing between yttria-doped zirconia (ZrO₂) and an electrically insulating ceramic joining partner is necessary for a wide range of applications in oxygen sensing and energy conversion. To accomplish this, laser brazing with glass solders is an attractive alternative to existing joining processes. Due to a near-perfect match of its thermal expansion with the one of ZrO₂ up to high temperatures (～800 °C) and good thermal and electrical insulation properties, forsterite (Mg₂SiO₄) is chosen as a candidate joining partner. As the absorptivity of pure forsterite at the used diode laser wavelengths of 808 and 940 nm is quite low, increasing the energy absorption by doping forsterite with Fe₂O₃ appears to be a promising refinement of this technique. The optical properties of the resulting olivine ceramics are evaluated. The results show that Fe₂O₃-doped forsterite is both suitable as a joining partner for ZrO₂ and for tuning its absorptivity.     

Assessing the value of climate assessments: Progress and future directions.

The authors synthesize existing climate research and climate instruments, as well as introduce several frameworks to help educators understand how institutions and researchers have assessed diversity in the college environment. Over 90 instruments were reviewed and examined for their attention to multiple dimensions of the campus climate, diversity initiatives, and outcomes measures that capture students' values, skills, and knowledge for participation in a diverse society. Frameworks presented include a broad definition of the campus climate, a typology of campus initiatives based on an inventory of campus practice, and a typology of representative outcomes that capture cognitive, socio-cognitive, values/attitudes, and preparation for a multicultural society. Campuses that strive to become functional multicultural learning environments can now rely on a body of empirical information to guide practice and critical self-assessment to deepen their commitment to diversity. The authors recommend that campuses integrate their assessment of the climate with the evaluation of student outcomes and campus practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)