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61.
62.
David Kuťák Pere-Pau Vázquez Tobias Isenberg Michael Krone Marc Baaden Jan Byška Barbora Kozlíková Haichao Miao 《Computer Graphics Forum》2023,42(6):e14738
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. 相似文献
63.
Prasant Ku. Dash Lopamudra Hota Madhumita Panda N. Z. Jhanjhi Kshira Sagar Sahoo Mehedi Masud 《计算机系统科学与工程》2023,44(3):2225-2242
The 3D Underwater Sensor Network (USNs) has become the most optimistic medium for tracking and monitoring underwater environment. Energy and collision are two most critical factors in USNs for both sparse and dense regions. Due to harsh ocean environment, it is a challenge to design a reliable energy efficient with collision free protocol. Diversity in link qualities may cause collision and frequent communication lead to energy loss; that effects the network performance. To overcome these challenges a novel protocol Forwarder Selection Energy Efficient Routing (FSE2R) is proposed. Our proposal’s key idea is based on computation of node distance from the sink, Residual Energy (RE) of each node and Signal to Interference Noise Ratio (SINR). The node distance from sink and RE is computed for reliable forwarder node selection and SINR is used for analysis of collision. The novel proposal compares with existing protocols like H2AB, DEEP, and E2LR to achieve Quality of Service (QoS) in terms of throughput, packet delivery ratio and energy consumption. The comparative analysis shows that FSE2R gives on an average 30% less energy consumption, 24.62% better PDR and 48.31% less end-to-end delay compared to other protocols. 相似文献
64.
Broadband Light Absorption and Efficient Charge Separation Using a Light Scattering Layer with Mixed Cavities for High‐Performance Perovskite Photovoltaic Cells with Stability 下载免费PDF全文
Byeong Cheul Moon Jung Hyo Park Dong Ki Lee Nikolai Tsvetkov Ilwoo Ock Kyung Min Choi Jeung Ku Kang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(30)
CH3NH3PbI3 is one of the promising light sensitizers for perovskite photovoltaic cells, but a thick layer is required to enhance light absorption in the long‐wavelength regime ranging from PbI2 absorption edge (500 nm) to its optical band‐gap edge (780 nm) in visible light. Meanwhile, the thick perovskite layer suppresses visible‐light absorption in the short wavelengths below 500 nm and charge extraction capability of electron–hole pairs produced upon light absorption. Herein, we find that a new light scattering layer with the mixed cavities of sizes in 100 and 200 nm between transparent fluorine‐doped tin oxide and mesoporous titanium dioxide electron transport layer enables full absorption of short‐wavelength photons (λ < 500 nm) to the perovskite along with enhanced absorption of long‐wavelength photons (500 nm < λ < 780 nm). Moreover, the light‐driven electric field is proven to allow efficient charge extraction upon light absorption, thereby leading to the increased photocurrent density as well as the fill factor prompted by the slow recombination rate. Additionally, the photocurrent density of the cell with a light scattering layer of mixed cavities is stabilized due to suppressed charge accumulation. Consequently, this work provides a new route to realize broadband light harvesting of visible light for high‐performance perovskite photovoltaic cells. 相似文献
65.
BJ van Vlijmen NJ Pearce M Berg? B Staels JW Yates AD Gribble BC Bond MH Hofker LM Havekes PH Groot 《Canadian Metallurgical Quarterly》1998,48(4):396-402
PURPOSE: We report an investigation into the distribution of proteoglycans (PGs) in normal, organ-cultured and dextran-treated human corneas. METHODS: Immunogold labeling was carried out at the electron microscope level to localize keratan sulphate (KS), chondroitin sulphate (CS), and heparan sulphate (HS) PGs. RESULTS: High levels of labeling for CS was found in the epithelium, endothelium, and keratocytes, with light labelling present in the basement membranes and the corneal stroma. Labeling for HS was present in the epithelium, endothelium, and keratocytes, with intense labeling present at the endothelium/Descemet's membrane interface and the epithelium/Bowman's layer interface. Large filaments were also observed in these regions in cuprolinic blue-stained specimens. Keratan sulphate was present at high levels in the stroma and the basement membranes with low levels present within the keratocytes, epithelium, and endothelium. The pattern of KS labeling along the collagen fibrils in the stroma sometimes showed evidence of periodicity. Organ-cultured corneas had extensive collagen-free "lakes," the interior of which immunolabeled positively for KS and showed staining with cuprolinic blue. The lakes were greatly reduced in the dextran-treated samples. CONCLUSION: This investigation determined the ultrastructural distribution of KS, CS, and HS PGs in human cornea and showed that organ culture is associated with a change in distribution of stromal PGs. 相似文献
66.
K. Kumagai S. Ikeda J. Jiang M. S. Lin C. C. Lai H. C. Ku 《Journal of Low Temperature Physics》1996,105(5-6):1641-1646
195Pt-,139La- and11B-NMR have been investigated in quaternary RM2B2C (R=Y, La, Th and M=Ni, Pd, Pt). The electric quadrupole frequency of139La changes more than 5 times in magnitude from M=Ni to Pt, indicating that the hybridization of La-5d and d-electrons of M-element changes largely. The analysis of11B and139La spectra shows also the large change of the magnetic anisotropy with R and M element, i.e., II c>II ab in LaNi2B2C, but II c>II ab YNi2B2C.The data of T1T and K of195Pt and11B are consistent with the band effects and with no evidence of strong antiferromagnetic correlation effects. 相似文献
67.
68.
The immunity protein of colicin E7 (ImmE7) can bind specifically to the DNase-type colicin E7 and inhibit its bactericidal activity. Here we report the 1.8-angstrom crystal structure of the ImmE7 protein. This is the first x-ray structure determined in the superfamily of colicin immunity proteins. The ImmE7 protein consists of four antiparallel alpha-helices, folded in a topology similar to the architecture of a four-helix bundle structure. A region rich in acidic residues is identified. This negatively charged area has the greatest variability within the family of DNase-type immunity proteins; thus, it seems likely that this area is involved in specific binding to colicin. Based on structural, genetic, and kinetic data, we suggest that all the DNase-type immunity proteins, as well as colicins, share a "homologous-structural framework" and that specific interaction between a colicin and its cognate immunity protein relies upon how well these two proteins' charged residues match on the interaction surface, thus leading to specific immunity of the colicin. 相似文献
69.
Wen-Jer Chang Liang-Zhi Liu Cheung-Chieh Ku 《International Journal of Control, Automation and Systems》2011,9(3):550-557
This paper investigates the fuzzy control problem of a class of nonlinear continuous-time stochastic systems with achieving
the passivity performance. A model-based observer feedback fuzzy control utilizing the concept of so-called parallel distributed
compensation (PDC) is employed to stabilize the class of nonlinear stochastic systems that are represented by the Takagi-Sugeno
(T-S) fuzzy models. Based on the Lyapunov criteria, the Linear Matrix Inequality (LMI) technique is used to synthesize the
observer feedback fuzzy controller design such that the closed-loop system satisfies stability and passivity constraints,
simultaneously. Finally, a numerical example is given to demonstrate the applicability and effectiveness of the proposed design
method. 相似文献
70.
In this paper we study a class of CQ Horn functions introduced in Boros et al. (Ann Math Artif Intell 57(3–4):249–291, 2010). We prove that given a CQ Horn function f, the maximal number of pairwise disjoint essential sets of implicates of f equals the minimum number of clauses in a CNF representing f. In other words, we prove that the maximum number of pairwise disjoint essential sets of implicates of f constitutes a tight lower bound on the size (the number of clauses) of any CNF representation of f. 相似文献