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Kotranza A Lind DS Lok B 《IEEE transactions on visualization and computer graphics》2012,18(7):1101-1114
We investigate the efficacy of incorporating real-time feedback of user performance within mixed-reality environments (MREs) for training real-world tasks with tightly coupled cognitive and psychomotor components. This paper presents an approach to providing real-time evaluation and visual feedback of learner performance in an MRE for training clinical breast examination (CBE). In a user study of experienced and novice CBE practitioners (n = 69), novices receiving real-time feedback performed equivalently or better than more experienced practitioners in the completeness and correctness of the exam. A second user study (n = 8) followed novices through repeated practice of CBE in the MRE. Results indicate that skills improvement in the MRE transfers to the real-world task of CBE of human patients. This initial case study demonstrates the efficacy of MREs incorporating real-time feedback for training real-world cognitive-psychomotor tasks. 相似文献
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DNA methylation is a prevalent regulatory modification in prokaryotes and eukaryotes. N1-methyladenine (m1A) and N6-methyladenine (m6A) have been found to be capable of altering DNA structures via disturbing Watson–Crick base pairing. However, little has been known about their influences on non-B DNA structures, which are associated with genetic instabilities. In this work, we investigated the effects of m1A and m6A on both the structure and thermodynamic stability of a newly reported DNA minidumbbell formed by two TTTA tetranucleotide repeats. As revealed by the results of nuclear magnetic resonance spectroscopic studies, both m1A and m6A favored the formation of a T·m1A and T·m6A Hoogsteen base pair, respectively. More intriguingly, the m1A and m6A modifications brought about stabilization and destabilization effects on the DNA minidumbbell, respectively. This work provides new biophysical insights into the effects of adenine methylation on the structure and thermodynamic stability of DNA. 相似文献
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A simplified method was proposed for the design of concrete lining in underground rock cavern/tunnel against shock loading.
The loading may result from the detonation of explosives on ground surface or ground penetration projectiles exploding adjacent
to the cavern/tunnel. The resulting problem necessitates the solution of the dynamics of a beam loaded by a transient pressure
uniformly distributed over the span. According to mechanical characteristics of the system with rock bolt and shotcrete, a
dynamic support design method based on equivalent single degree of freedom (SDOF) was put forward. The SDOF method was applied
to obtaining the maximum displacement at the mid-span of the beam, which is often the controlling factor in the blast-resistant
design. In the formulation of the problem, the proposed method combines the phenomena of spalling and structural dynamics
theory. An example is provided to demonstrate the applicability of this simplified method. 相似文献
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Sheng Yan Lok Yan Yim Rachel Chun Yee Tam Albert Chan Liwei Lu Chak Sing Lau Vera Sau-Fong Chan 《International journal of molecular sciences》2016,17(8)
Systemic lupus erythematosus (SLE) is a chronic multi-organ autoimmune disease characterized by hyperactivated immune responses to self-antigens and persistent systemic inflammation. Previously, we reported abnormalities in circulating and bone marrow (BM)-derived plasmacytoid dendritic cells (pDCs) from SLE patients. Here, we aim to seek for potential regulators that mediate functional aberrations of pDCs in SLE. BM-derived pDCs from NZB/W F1 mice before and after the disease onset were compared for toll-like receptor (TLR) induced responses and microRNA profile changes. While pDCs derived from symptomatic mice were phenotypically comparable to pre-symptomatic ones, functionally they exhibited hypersensitivity to TLR7 but not TLR9 stimulation, as represented by the elevated upregulation of CD40, CD86 and MHC class II molecules upon R837 stimulation. Upregulated induction of miR-155 in symptomatic pDCs following TLR7 stimulation was observed. Transfection of miR-155 mimics in pre-symptomatic pDCs induced an augmented expression of Cd40, which is consistent with the increased CD40 expression in symptomatic pDCs. Overall, our results provide evidence for miR-155-mediated regulation in pDC functional abnormalities in SLE. Findings from this study contribute to a better understanding of SLE pathogenesis and ignite future interests in evaluating the molecular regulation in autoimmunity. 相似文献
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Taotao Zou Jing-Jing Zhang Bei Cao Ka-Chung Tong Chun-Nam Lok Chi-Ming Che 《Israel journal of chemistry》2016,56(9-10):825-833
Metal-based anticancer agents with non-DNA targets are anticipated for overcoming cisplatin resistance problems. Gold complexes are generally known to undergo ligand exchange or redox reactions with thiols, and hence, are potentially useful agents that could target thiol-containing enzymes, but not DNA. Recent studies have shown that deubiquitinases (DUBs), key enzymes regulating proteasome-related protein homeostasis, are potential anticancer targets of both gold(I) and gold(III) complexes. In this review, the current status of gold complexes as DUB inhibitors is discussed. In particular, auranofin and cyclometalated gold(III) complexes containing dithiocarbamate ligands (e.g., [(AuIII(C N)(DEDT)]+, HC N=2-phenylpyridine, DEDT=diethyldithiocarbamate) are highlighted as examples of DUB inhibitors. The mechanisms of their anticancer action, together with in vitro and/or in vivo antitumor potencies, are also explored. 相似文献
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The rapid SafTest PeroxySafe? MSA Kit (PeroxySafe method) was approved by the AOAC to determine peroxide values (PVs) in foods. Studies were conducted to remedy challenges (reaction time, lack of turbidity in samples, effect of prooxidant [NaCl]) for use of the method when analyzing PVs in turkey meat. Initially, PVs could not be consistently obtained after a reaction time of 10 min (per directions) for variously processed meat. However, trends indicated that heated and heated/stored samples generally had higher numerical values than Fresh ones. This trend agreed with that of other investigators, suggesting usefulness of the method if consistent data could be obtained. Data for PVs of all treatments within processing conditions were recorded at 10, 20, and 30 min. There was a highly significant (P ≤ 0.0001) effect for reaction time with 30 min > 20 min > 10 min. An increase in PVs was noted for heated samples when lipids and oxidation products were released by homogenization, rather than vortexing with glass beads, and data were recorded at the 30 min. It is likely that these precautions may promote more accurate determination of PVs from samples with NaCl, a prooxidant. Comparison of extraction procedures for the PeroxySafe method and that of Grau and others (2000) showed that the extraction procedure (homogenization) of the latter method produced numerically greater PVs for fresh/stored samples than that of the former. However, it was concluded that the PeroxySafe method could be used for comparative analyses of samples when adequate extraction (turbidity) occurred and measurements were recorded after a 20 to 30 min reaction time. 相似文献