Summary Reviving the past: Cultural Heritage meets Virtual Reality

The use of immersive virtual reality (VR) systems in museums is a recent trend, as the development of new interactive technologies has inevitably impacted the more traditional sciences and arts. This is more evident in the case of novel interactive technologies that fascinate the broad public, as has always been the case with virtual reality. The increasing development of VR technologies has matured enough to expand research from the military and scientific visualization realm into more multidisciplinary areas, such as education, art and entertainment. This paper analyzes the interactive virtual environments developed at an institution of informal education and discusses the issues involved in developing immersive interactive virtual archaeology projects for the broad public

Efficient Occlusion Culling using Solid Occluders

Occlusion culling is a genre of algorithms for rapidly eliminating portions of three-dimensional geometry hidden behind other, visible objects prior to passing them to the rendering pipeline. In this paper, an extension to the popular shadow frustum culling algorithm is presented, which takes into account the fact that many planar occluders can be grouped into compound convex solids, which in turn can provide fewer and larger culling frusta and therefore more efficient elimination of hidden geometry. The proposed method combines planar and solid occluders using a unified selection approach and is ideal for dynamic environments, as it doesn’t depend on precalculated visibility data. The solid occluders culling algorithm has been applied to commercially deployed virtual reality systems and test cases and results are provided from actual virtual reality shows

Reviving the Past: Cultural Heritage Meets Virtual Reality

This paper analyzes the interactive virtual environments developed at an institution of informal education and discusses the issues involved in developing immersive interactive virtual archaeology projects for the broad publi

Virtual Reality Interfaces for the Broad Public

This paper analyses the direction taken regarding the development of user friendly interfaces and natural modes of interaction for users of varied technical competencies in virtual environment

Presampled visibility for ambient occlusion

We present a novel method to accelerate the computation of the visibility function of the lighting equation, in dynamic scenes composed of rigid, non-penetrating objects. The main idea of the technique is to pre-compute for each object in the scene its associated four-dimensional field that describes the visibility in each direction for all positional samples on a sphere around the object, we call this a displacement field. We are able to speed up the calculation of algorithms that trace visibility rays to near real time frame rates. The storage requirements of the technique, amounts from one byte to one bit per ray direction making it particularly attractive to scenes with multiple instances of the same object, as the same cached data can be reused, regardless of the geometric transformation applied to each instance. We suggest an acceleration technique and identify the sampling method that gives the best results based on experimentation

Fast Approximate Visibility on the GPU using precomputed 4D Visibility Fields

We present a novel GPU-based method for accelerating the visibility function computation of the lighting equation in dynamic scenes composed of rigid objects. The method pre-computes, for each object in the scene, the visibility and normal information, as seen from the environment, onto the bounding sphere surrounding the object and encodes it into maps. The visibility function is encoded by a four-dimensional visibility field that describes the distance of the object in each direction for all positional samples on a sphere around the object. In addition, the normal vectors of each object are computed and stored in corresponding fields for the same positional samples for use in the computation of reflection in ray-tracing. Thus we are able to speed up the calculation of most algorithms that trace rays to real-time frame rates. The pre-computation time of our method is relatively small. The space requirements amount to 1 byte per ray direction for the computation of ambient occlusion and soft shadows and 4 bytes per ray direction for the computation of reflection in ray-tracing. We present the acceleration results of our method and show its application to two different intersection intensive domains, ambient occlusion computation and stochastic ray tracing on the GPU

Hellenic Cultural Heritage through Immersive Virtual Archaeology

Abstract. Virtual Reality is a novel and innovative technology which allows us, through its applications, to experience abstract concepts and ideas, visit spaces that are unreachable or no longer exist, and examine e objects from diverse and unique points of view. Virtual archaeology refers to the use of 3D computer models of ancient buildings and artifacts visualized through immersive technologies. In this paper we explore issues involved in creating immersive cultural heritage projects enhancing our perspective and understanding of the environments in which our ancestors lived and worked. Research in virtual reality (VR) and archeology is a relatively young field which has shown considerable growth in recent years, as the development of new interactive technologies has inevitably impacted the more traditional sciences and arts. This is more evident in the case of novel interactive technologies that fascinate the broad public, as has always been the case with virtual reality. The increasing development of VR technologies has matured enough to expand research from the military and scientific visualization realm into more multidisciplinary areas, such as archeology, education, art, and psychology

Chromoanasynthesis is a common mechanism that leads to ERBB2 amplifications in a cohort of early stage HER2+ breast cancer samples

Abstract Background HER2 positive (HER2+) breast cancers involve chromosomal structural alterations that act as oncogenic driver events. Methods We interrogated the genomic structure of 18 clinically-defined HER2+ breast tumors through integrated analysis of whole genome and transcriptome sequencing, coupled with clinical information. Results ERBB2 overexpression in 15 of these tumors was associated with ERBB2 amplification due to chromoanasynthesis with six of them containing single events and the other nine exhibiting multiple events. Two of the more complex cases had adverse clinical outcomes. Chromosomes 8 was commonly involved in the same chromoanasynthesis with 17. In ten cases where chromosome 8 was involved we observed NRG1 fusions (two cases), NRG1 amplification (one case), FGFR1 amplification and ADAM32 or ADAM5 fusions. ERBB3 over-expression was associated with NRG1 fusions and EGFR and ERBB3 expressions were anti-correlated. Of the remaining three cases, one had a small duplication fully encompassing ERBB2 and was accompanied with a pathogenic mutation. Conclusion Chromoanasynthesis involving chromosome 17 can lead to ERBB2 amplifications in HER2+ breast cancer. However, additional large genomic alterations contribute to a high level of genomic complexity, generating the hypothesis that worse outcome could be associated with multiple chromoanasynthetic events

Additional file 1: of Chromoanasynthesis is a common mechanism that leads to ERBB2 amplifications in a cohort of early stage HER2+ breast cancer samples

Figure S1-S17. Genome U plots of all the additional cases. Figure S18 Heat map of the EGFR and ERBB3 expression log2 expression by RNAseq. Dark red indicates low expression where yellow indicates high expression. Table S1 BRISQ summary of tumor specimens. (PPTX 3536 kb