1,877 research outputs found
Effect of Trust in Metaverse on Usage Intention through Technology Readiness and Technology Acceptance Model
The fourth industrial revolution enhanced the development of information technology in all fields and opened up possibilities. A lot of attention is focused on the future possibilities opened up by the metaverse, the core of information technology. Metaverse will have a big impact on reality and the near future. Metaverse is a virtual world that fuses physical and digital reality. Various commerce such as healthcare, instruction, business, and land are foundation to utilize metaverse knowledge in their regular work. There is a series of processes in the stage where newly developed technology is introduced to general users. In order for a new technology to become a user-friendly technology, it is necessary to verify the technology. It can be said that it is hard to derive the operator\u27s usage intention in a state where user trust for new technology is not verified. In the metaverse environment, it is necessary to first verify the trust for new technologies. This study is expected to understand usage intention through the process of checking trust in metaverse, and to become basic data for the popularization of metaverse knowledge. The meaning of this research is to inspect the influence relationship of trust in metaverse on usage intention through Technology Readiness (TR) and Technology Acceptance Model (TAM). Statistical package (SPSS23.0) was used for basic numerical examination of the questionnaire. Hypothesis test was performed using the structural equation package Smart PLS 3.0. Discriminant validity and concentration validity of the questionnaire were verified. As parameters that trust in metaverse effects, TR and TAM were set. As factors constituting TR, it was separated into optimism, innovativeness, discomfort, and insecurity. The TAM is separated into perceived usefulness and perceived ease of use. The outcomes of the study are as follows. First, trust in metaverse had a significant effect on TR. Second, TR was partially adopted in the TAM. Innovativeness and perceived usefulness had no significant effect. Third, TAM significantly influences usage intention. Fourth, perceived ease of use did not significantly influence perceived usefulness
Strong and Reversible Adhesion of Interlocked 3D-Microarchitectures
Diverse physical interlocking devices have recently been developed based on one-dimensional (1D), high-aspect-ratio inorganic and organic nanomaterials. Although these 1D nanomaterial-based interlocking devices can provide reliable and repeatable shear adhesion, their adhesion in the normal direction is typically very weak. In addition, the high-aspect-ratio, slender structures are mechanically less durable. In this study, we demonstrate a highly flexible and robust interlocking system that exhibits strong and reversible adhesion based on physical interlocking between three-dimensional (3D) microscale architectures. The 3D microstructures have protruding tips on their cylindrical stems, which enable tight mechanical binding between the microstructures. Based on the unique 3D architectures, the interlocking adhesives exhibit remarkable adhesion strengths in both the normal and shear directions. In addition, their adhesion is highly reversible due to the robust mechanical and structural stability of the microstructures. An analytical model is proposed to explain the measured adhesion behavior, which is in good agreement with the experimental results
COMBUSTION CHARACTERISTICS AND EMISSION OF HAZARDOUS AIR POLLUTANTS IN COMMERCIAL FLUIDIZED BED COMBUSTORS FOR SEWAGE SLUDGE
Since the disposal of sewage sludge in ocean has been prohibited recently according to London Dumping Convention, technological need for treating sewage sludge safely and efficiently are getting increased in Korea. FBC (Fluidized Bed Combustor) technology has been selected and utilized as one of the alternatives because of combustible content in sludge, on-going process development to maintain the best combustion efficiency, and good heat recovery for energy utilization. In this paper, the process and combustion characteristics of commercially operating FBC incineration plants with the capacity ranging from 50 – 150 tons of sludge per day were investigated by comparing emission data from 4 different plants. Concentrations of hazardous gaseous pollutants (HAPs) such as fine particulate matter, heavy metals, and dioxin from sludge combustion before and after air pollution control devices were measured and analyzed at commercial operating conditions of one typical incinerator. Most of emission data at stack showed under the environmental regulatory limits. Mercury and some heavy metals emission have been reduced significantly as co-beneficial effect since the air pollution control configuration was well arranged and installed to control the regulatory gases such as NOx, SO2, particulates, and dioxin. Sludge, especially generated from industrial plants, contained measurable amounts of acidic materials and heavy metals including Hg. Therefore, such metal emission should receive an attention by monitoring them and further mass balance study for better understanding their fates in the process must proceed in future
Flexible and Shape-Reconfigurable Hydrogel Interlocking Adhesives for High Adhesion in Wet Environments Based on Anisotropic Swelling of Hydrogel Microstructures
This study presents wet-responsive, shape-reconfigurable, and flexible hydrogel adhesives that exhibit strong adhesion under wet environments based on reversible interlocking between reconfigurable microhook arrays. The experimental investigation on the swelling behavior and structural characterization of the hydrogel microstructures reveal that the microhook arrays undergo anisotropic swelling and shape transformation upon contact with water. The adhesion between the interlocked microhook arrays is greatly enhanced under wet conditions because of the hydration-triggered shape reconfiguration of the hydrogel microstructures. Furthermore, wet adhesion monotonically increases with water-exposure time. A maximum adhesion force of 79.9 N cm-2 in the shear direction is obtained with the hydrogel microhook array after 20 h of swelling, which is 732.3% greater than that under dry conditions (i.e., 9.6 N cm-2). A simple theoretical model is developed to describe the measured adhesion forces. The results are in good agreement with the experimental data
Predictive Scale for Amyloid PET Positivity Based on Clinical and MRI Variables in Patients with Amnestic Mild Cognitive Impairment
The presence of amyloid-β (Aβ) deposition is considered important in patients with amnestic mild cognitive impairment (aMCI), since they can progress to Alzheimer's disease dementia. Amyloid positron emission tomography (PET) has been used for detecting Aβ deposition, but its high cost is a significant barrier for clinical usage. Therefore, we aimed to develop a new predictive scale for amyloid PET positivity using easily accessible tools. Overall, 161 aMCI patients were recruited from six memory clinics and underwent neuropsychological tests, brain magnetic resonance imaging (MRI), apolipoprotein E (APOE) genotype testing, and amyloid PET. Among the potential predictors, verbal and visual memory tests, medial temporal lobe atrophy, APOE genotype, and age showed significant differences between the Aβ-positive and Aβ-negative groups and were combined to make a model for predicting amyloid PET positivity with the area under the curve (AUC) of 0.856. Based on the best model, we developed the new predictive scale comprising integers, which had an optimal cutoff score ≥ 3. The new predictive scale was validated in another cohort of 98 participants and showed a good performance with AUC of 0.835. This new predictive scale with accessible variables may be useful for predicting Aβ positivity in aMCI patients in clinical practice
Sequences of the Cytochrome C Oxidase Subunit I (COI) Gene are Suitable for Species Identification of Korean Calliphorinae Flies of Forensic Importance (Diptera: Calliphoridae)
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75068/1/j.1556-4029.2009.01126.x.pd
L-Type Ca2+ Channel Inhibition Rescues the LPS-Induced Neuroinflammatory Response and Impairments in Spatial Memory and Dendritic Spine Formation
Ca2+ signaling is implicated in the transition between microglial surveillance and activation. Several L-type Ca2+ channel blockers (CCBs) have been shown to ameliorate neuroinflammation by modulating microglial activity. In this study, we examined the effects of the L-type CCB felodipine on LPS-mediated proinflammatory responses. We found that felodipine treatment significantly diminished LPS-evoked proinflammatory cytokine levels in BV2 microglial cells in an L-type Ca2+ channel-dependent manner. In addition, felodipine leads to the inhibition of TLR4/AKT/STAT3 signaling in BV2 microglial cells. We further examined the effects of felodipine on LPS-stimulated neuroinflammation in vivo and found that daily administration (3 or 7 days, i.p.) significantly reduced LPS-mediated gliosis and COX-2 and IL-1?? levels in C57BL/6 (wild-type) mice. Moreover, felodipine administration significantly reduced chronic neuroinflammation-induced spatial memory impairment, dendritic spine number, and microgliosis in C57BL/6 mice. Taken together, our results suggest that the L-type CCB felodipine could be repurposed for the treatment of neuroinflammation/cognitive function-associated diseases
Phosphorylation of p62 by AMP-activated protein kinase mediates autophagic cell death in adult hippocampal neural stem cells
In the adult brain, programmed death of neural stem cells is considered to be critical for tissue homeostasis and cognitive function and is dysregulated in neurodegeneration. Previously, we have reported that adult rat hippocampal neural (HCN) stem cells undergo autophagic cell death (ACD) following insulin withdrawal. Because the apoptotic capability of the HCN cells was intact, our findings suggested activation of unique molecular mechanisms linking insulin withdrawal to ACD rather than apoptosis. Here, we report that phosphorylation of autophagy-associated protein p62 by AMP-activated protein kinase (AMPK) drives ACD and mitophagy in HCN cells. Pharmacological inhibition of AMPK or genetic ablation of the AMPK alpha 2 subunit by clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing suppressed ACD, whereas AMPK activation promoted ACD in insulin-deprived HCN cells. We found that following insulin withdrawal AMPK phosphorylated p62 at a novel site, Ser-293/Ser-294 (in rat and human p62, respectively). Phosphorylated p62 translocated to mitochondria and induced mitophagy and ACD. Interestingly, p62 phosphorylation at Ser-293 was not required for staurosporine-induced apoptosis in HCN cells. To the best of our knowledge, this is the first report on the direct phosphorylation of p62 by AMPK. Our data suggest that AMPK-mediated p62 phosphorylation is an ACD-specific signaling event and provide novel mechanistic insight into the molecular mechanisms in ACD.1
- …