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Cerebral hypoxia is a serious consequence of several cardiorespiratory illnesses. Measuring the retinal microvasculature at high altitude provides a surrogate for cerebral microvasculature, offering potential insight into cerebral hypoxia in critical illness. In addition, although sex-specific differences in cardiovascular diseases are strongly supported, few have focused on differences in ocular blood flow. We evaluated the retinal microvasculature in males (n = 11) and females (n = 7) using functional optical coherence tomography at baseline (1,130 m) (day 0), following rapid ascent (day 2), and prolonged exposure (day 9) to high altitude (3,800 m). Retinal vascular perfusion density (rVPD; an index of total blood supply), retinal thickness (RT; reflecting vascular and neural tissue volume), and arterial blood were acquired. As a group, rVPD increased on day 2 versus day 0 (P < 0.001) and was inversely related to [Formula: see text] (R2 = 0.45; P = 0.006). By day 9, rVPD recovered to baseline but was significantly lower in males than in females (P = 0.007). RT was not different on day 2 versus day 0 (P > 0.99) but was reduced by day 9 relative to day 0 and day 2 (P < 0.001). RT changes relative to day 0 were inversely related to changes in [Formula: see text] on day 2 (R2 = 0.6; P = 0.001) and day 9 (R2 = 0.4; P = 0.02). RT did not differ between sexes. These data suggest differential time course and regulation of the retina during rapid ascent and prolonged exposure to high altitude and are the first to demonstrate sex-specific differences in rVPD at high altitude. The ability to assess intact microvasculature contiguous with the brain has widespread research and clinical applications.NEW & NOTEWORTHY Measuring the retinal microvasculature at high altitude provides a surrogate for cerebral microvasculature, offering potential insight into consequence of cerebral hypoxia in critical illness. This study demonstrates dynamic regulation of the retina during rapid ascent and prolonged exposure to high altitude and is the first to demonstrate sex-specific differences in retinal microvasculature at high altitude. The ability to dynamically assess intact microvasculature contiguous with the brain has widespread research and clinical applications.

Interpolation is a foundational concept in scientific computing and is at the heart of many scientific visualization techniques. There is usually a tradeoff between the approximation capabilities of an interpolation scheme and its evaluation efficiency. For many applications, it is important for a user to navigate their data in real time. In practice, evaluation efficiency outweighs any incremental improvements in reconstruction fidelity. We first analyze, from a general standpoint, the use of compact piece-wise polynomial basis functions to efficiently interpolate data that is sampled on a lattice. We then detail our automatic code-generation framework on both CPU and GPU architectures. Specifically, we propose a general framework that can produce a fast evaluation scheme by analyzing the algebro-geometric structure of the convolution sum for a given lattice and basis function combination. We demonstrate the utility and generality of our framework by providing fast implementations of various box splines on the Body Centered and Face Centered Cubic lattices, as well as some non-separable box splines on the Cartesian lattice. We also provide fast implementations for certain Voronoi-splines that have not yet appeared in the literature. Finally, we demonstrate that this framework may also be used for non-Cartesian lattices in 4D. [ABSTRACT FROM AUTHOR]

In this paper, we extend the single relaxation time Lattice-Boltzmann Method (LBM) to the 3D body-centered cubic (BCC) lattice. We show that the D3bQ15 lattice defined by a 15 neighborhood connectivity of the BCC lattice is not only capable of more accurately discretizing the velocity space of the continuous Boltzmann equation as compared to the D3Q15 Cartesian lattice, it also achieves a comparable spatial discretization with 30 percent less samples. We validate the accuracy of our proposed lattice by investigating its performance on the 3D lid-driven cavity flow problem and show that the D3bQ15 lattice offers significant cost savings while maintaining a comparable accuracy. We demonstrate the efficiency of our method and the impact on graphics and visualization techniques via the application of line-integral convolution on 2D slices as well as the extraction of streamlines of the 3D flow. We further study the benefits of our proposed lattice by applying it to the problem of simulating smoke and show that the D3bQ15 lattice yields more detail and turbulence at a reduced computational cost. [ABSTRACT FROM AUTHOR]

In this paper, we present two methods for accurate gradient estimation from scalar field data sampled on regular lattices. The first method is based on the multidimensional Taylor series expansion of the convolution sum and allows us to specify design criteria such as compactness and approximation power. The second method is based on a Hilbert space framework and provides a minimum error solution in the form of an orthogonal projection operating between two approximation spaces. Both methods lead to discrete filters, which can be combined with continuous reconstruction kernels to yield highly accurate estimators as compared to the current state of the art. We demonstrate the advantages of our methods in the context of volume rendering of data sampled on Cartesian and Body-Centered Cubic lattices. Our results show significant qualitative and quantitative improvements for both synthetic and real data, while incurring a moderate preprocessing and storage overhead. [ABSTRACT FROM PUBLISHER]

We investigate the use of a Fourier-domain derivative error kernel to quantify the error incurred while estimating the gradient of a function from scalar point samples on a regular lattice. We use the error kernel to show that gradient reconstruction quality is significantly enhanced merely by shifting the reconstruction kernel to the centers of the principal lattice directions. Additionally, we exploit the algebraic similarities between the scalar and derivative error kernels to design asymptotically optimal gradient estimation filters that can be factored into an infinite impulse response interpolation prefilter and a finite impulse response directional derivative filter. This leads to a significant performance gain both in terms of accuracy and computational efficiency. The interpolation prefilter provides an accurate scalar approximation and can be re-used to cheaply compute directional derivatives on-the-fly without the need to store gradients. We demonstrate the impact of our filters in the context of volume rendering of scalar data sampled on the Cartesian and Body-Centered Cubic lattices. Our results rival those obtained from other competitive gradient estimation methods while incurring no additional computational or storage overhead. [ABSTRACT FROM PUBLISHER]

This article attempts to fill the gap in the very limited knowledge of the history of Islam and Muslim intellectual tradition in Mindanao in the 19th century. It particularly deals with a set of primary sources of Islamic manuscripts recently found in the Lanao area of Mindanao, southern Philippines, which formerly belonged to a Maranao ulama, Aleem Ulomuddin Said, who inherited the manuscripts from his father, Sheikh Muhammad Said bin Imam sa Bayang (1904-1974). This manuscript collection contains several texts written in Malay, Arabic, and Maranao languages on various fields. I will argue that these manuscripts indicate the close contact Muslim communities of Mindanao developed during the 18th and 19th centuries with their Malay colleagues, especially those in Aceh and Banten. It also confirms their network with the wider Islamic world, more specifically with Mecca and Medina through the Shaṭṭārīyah Sufi order. The manuscript content in this collection confirms that the 19th century Mindanao Muslim authors referred to both Arab and Malay sources. This not only underlines the importance of the Malay scholars but also suggests that the development of the Islamic intellectual tradition in Mindanao came rather late in the 19th century. [ABSTRACT FROM AUTHOR]

The article presents information on importance of machine learning; table of contents for scalar field analysis, biomedical visualization and data processing; and preface of Eurographics Computer Graphics Forum journal.

The cove page of the journal "Eurographics 2016" is presented.

The article presents miscellaneous topics related to the June 2015 issue of the journal including table of contents, list of International Programme Committee members including Tim Dwyer, Achim Ebert and Christoph Garth, and list of reviewers including Yael Albo, Fabian Beck and Liang Jie.

B EuroVis 2021 b B 23rd Eurographics Conference on Visualization 2021 b Zurich, Switzerland (Virtual Conference) June 14 - 18, 2021 GLO:BNX/01jun21:cgf14328-gra-0001.jpg PHOTO (COLOR): . gl B General Chairs b Renato Pajarola, University of Zürich, Switzerland Tobias Günther, FAU Erlangen-Nürnberg, Germany B Full Papers Chairs b Rita Borgo, King's College London, UK G. Elisabeta Marai, University of Illinois at Chicago, USA Tatiana von Landesberger, University of Cologne and University of Rostock, Germany B STARs Chairs b Noeska Smit, University of Bergen, Norway Katerina Vrotsou, Linköping University, Sweden Bei Wang, University of Utah, USA B Short Papers Chairs b Marco Agus, Hamad bin Khalifa University, Qatar Christoph Garth, University of Kaiserslautern, Germany Andreas Kerren, Linnaeus University, Sweden B Posters Chairs b Jan Byska, Masaryk University, Czech Republic and University of Bergen, Norway Stefan Jänicke, University of Southern Denmark, Denmark Johanna Schmidt, VRVis Zentrum für Virtual Reality und Visualisierung Forschungs-GmbH, Austria B Workshop Chair b Jürgen Bernard, University of Zurich, Switzerland Sponsors GLO:BNX/01jun21:cgf14328-gra-0002.jpg PHOTO (COLOR): . gl Preface EuroVis 2021, the Eurographics / IEEE VGTC Conference on Visualization was scheduled to be held in Zürich, Switzerland from June 14 to June 18th, 2021. We were looking forward to bringing the international data visualization community together at the conference in Zürich. EuroVis also covers the theory of visualization, hardware acceleration, large datasets, perception, interaction, user studies, information visualization, visual analytics, and many application areas of visualization. [Extracted from the article]

A list of reviewers for the journal "Computer Graphics Forum" is presented, including Wolfgang Aigner, Linsen Lars and Michael Mara.