State of the Art of Molecular Visualization in Immersive Virtual Environments

Visualization plays a crucial role in molecular and structural biology. It has been successfully applied to a variety of tasks, including structural analysis and interactive drug design. While some of the challenges in this area can be overcome with more advanced visualization and interaction techniques, others are challenging primarily due to the limitations of the hardware devices used to interact with the visualized content. Consequently, visualization researchers are increasingly trying to take advantage of new technologies to facilitate the work of domain scientists. Some typical problems associated with classic 2D interfaces, such as regular desktop computers, are a lack of natural spatial understanding and interaction, and a limited field of view. These problems could be solved by immersive virtual environments and corresponding hardware, such as virtual reality head-mounted displays. Thus, researchers are investigating the potential of immersive virtual environments in the field of molecular visualization. There is already a body of work ranging from educational approaches to protein visualization to applications for collaborative drug design. This review focuses on molecular visualization in immersive virtual environments as a whole, aiming to cover this area comprehensively. We divide the existing papers into different groups based on their application areas, and types of tasks performed. Furthermore, we also include a list of available software tools. We conclude the report with a discussion of potential future research on molecular visualization in immersive environments.     

Insulin-like growth factor I-dependent regulation of prolidase activity in cultured human skin fibroblasts

In metastatic breast cancer the goal to reach must be the best possible palliation with minimum discomfort for the patient. We reviewed our experience with radiotherapy (20 or 30 Gy), systemic therapy and brace. Among 2200 breast cancer patients, we extracted 28 potential candidates for resection. All of them developed new metastases outside the treated field within one year. Local control was achieved in 68%, and 80% of them had stable or better performance status at 3 months. From our analysis, even patients with a so called "solitary lesion" do not seem to have a better prognosis than others. We conclude that radiotherapy (with systemic therapy and a brace) is still first-choice treatment for vertebral metastases; CT-guided percutaneous biopsy can avoid worthless major operations. The role of surgery should be limited to neurological compression, severe mechanical instability and to salvage the failures of conservative treatment.     

The squid picovoltmeter operating in magnetic fields up to 3.2 T

A method which enables the Squid dc voltmeter to be operated with a sample exposed to a significant external magnetic field is presented. A special superconducting shield with a finite time constant has been used to suppress time-dependent components of the field. With the shield, the Squid voltmeter has been able to work in magnetic fields up to 0.7 T in the flux-locked loop mode. The total voltage noise per unit bandwidth V_rms (referred to input) does not exceed the value of . To extend the range of performance to higher magnetic fields, simple low pass filters have been built into the input circuit to increase its time constant. With the signal coil of the Squid shunted by a resistor R_B = 3 × 10⁻⁶ω, the Squid voltmeter could be operated in fields up to 3.2 T with

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Heat denaturation of hemocytocardiotoxin from the venom of the Central Asian cobra

It has been stated that boiled for three hours haemocytocardiotoxin (HT) from cobra poison loses "direct" hemolytic activity and is unable to potentiate a haemolytic effect of phospholipase A. Surface activity of HT does not change. It is shown that in the course of heat denaturation the aggregation of toxin molecules to dimers and trimers takes place and electrophoretic mobility is decreased. The fluorescence of HT tyroxin residues supported the fact of its irreversible heat denaturation.     

Designing fast LTL model checking algorithms for many-core GPUs

Recent technological developments made various many-core hardware platforms widely accessible. These massively parallel architectures have been used to significantly accelerate many computation demanding tasks. In this paper, we show how the algorithms for LTL model checking can be redesigned in order to accelerate LTL model checking on many-core GPU platforms. Our detailed experimental evaluation demonstrates that using the NVIDIA CUDA technology results in a significant speedup of the verification process. Together with state space generation based on shared hash-table and DFS exploration, our CUDA accelerated model checker is the fastest among state-of-the-art shared memory model checking tools.     

Effect of the laser fusion of electrometallized coatings of the Fe-Cr-B-Al system on their corrosion resistance

We studied the effect of laser treatment of electric arc coatings produced of powder wires of the Fe-Cr-B system on the changes in their structure, electrolytic potential, and polarization currents. We additionally introduced aluminum, nickel, and copper to the charge of these coatings. Laser treatment was realized by means of Nd: YAG laser radiation. We have shown that the addition of a small amount of these elements to the coating under study in different ways affects the character of formation, structure, and electrochemical characteristics of the fused layer. In particular, copper and nickel additions increase the fluidity of the coating. The parameters of laser treatment affect strongly the uniformity of the distribution of elements in the fused zone. In the case of alloying with copper, the nonuniformity of their distribution is more pronounced, which can exert a slight negative influence on the corrosion characteristics of the coating. Aluminum addition improves the corrosion resistance of laser-modified coatings. __________ Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 42, No. 6, pp. 106–110, November–December, 2006.     

p‐version of the generalized FEM using mesh‐based handbooks with applications to multiscale problems

In this paper, we analyse the p‐convergence of a new version of the generalized finite element method (generalized FEM or GFEM) which employs mesh‐based handbook functions which are solutions of boundary value problems in domains extracted from vertex patches of the employed mesh and are pasted into the global approximation by the partition of unity method (PUM). We show that the p‐version of our GFEM is capable of achieving very high accuracy for multiscale problems which may be impossible to solve using the standard FEM. We analyse the effect of the main factors affecting the accuracy of the method namely: (a) The data and the buffer included in the handbook domains, and (b) The accuracy of the numerical construction of the handbook functions. We illustrate the robustness of the method by employing as model problem the Laplacian in a domain with a large number of closely spaced voids. Similar robustness can be expected for problems of heat‐conduction and elasticity set in domains with a large number of closely spaced voids, cracks, inclusions, etc. Copyright © 2004 John Wiley & Sons, Ltd.