2,024 research outputs found
Who Is Caring for the Caregiver? The Role of Cybercoping for Dementia Caregivers
The purpose of this study is to investigate the relationship between dementia caregivers’ communication behaviors (information seeking and forwarding) and their outcomes (coping outcomes: e.g., dealing better with negative feelings or improved medical outcomes). A survey data set of dementia patients’ caregivers substantiates the effects of communication behaviors about dementia illness on coping outcomes, as well as the mediating role of emotion-focused and problem-focused coping processes. Using structural equation modeling (SEM), this study found positive effects of communication behaviors on outcomes through coping processes. Further, the results indicate that communication behaviors in cyberspace are crucial for caregivers to cope with dementia, both affectively (improvement of caregivers’ emotional control) and physically (health improvement of patients). The implications for the improvement of public health through online health communication behaviors are discussed
The digital economy and the role of government
노트 : Program on Information Resources Polic
Effect of Angelica gigas Nakai extract on hepatic damage in rats
Purpose: To determine the antioxidant and hepatoprotective effects of decursin and decursinol angelate (D/DA) isolated from Angelica gigas Nakai (AGN).Methods: The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of D/DA was assessed in a rat model using blood tests, western blotting, and histopathological analyses to identify the pharmaceutical effects of D/DA on liver enzymes and liver morphology.Results: The DPPH scavenging activity of D/DA was 47.11 ÎĽg/mL. Administration of D/DA to carbon tetrachloride (CCl4)-treated rats led to a decrease (13.59 %) in the total liver mass of control rats. Decursin and decursinol angelate also lowered the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), but increased the concentrations of antioxidant enzymes in the liver, including catalase (CAT) and glutathione peroxidase (GPx). Histological examination revealed that D/DA also reduced hepatocellular damage in the rats.Conclusion: D/DA from AGN has significant anti-hepatotoxic and antioxidant activities, and thus, is a potential herbal drug for treating liver damage.
Keywords: Decursin, Decursinol angelate, Antihepatotoxicity, Antioxidant, Angelica gigas Naka
Sequential whole cell conversion process for production of D-psicose and D- mannitol from D-fructose
Rare sugars, which exist only limited quantities naturally, have received considerable attention because of its various specific nutritional and biological functions. Likewise, D-psicose (D-ribo-2-hexulose or D-allulose), a C-3 epimer of D-fructose, has many uses which include reducing intra-abdominal fat accumulation, protecting pancreas beta-islets and improving insulin sensitivity. Especially, D-psicose has only 0.3% calories compared to sucrose, while it has 70% relative sweetness. Additionally, in 2012, D-psicose was approved as a food additive and designated as Generally Recognized As Safe (GRAS) by Food and Drug Administration (FDA). Despite such abundant advantages, there is no economical way of mass production of D-psicose. Recently, biological production of D-psicose from D-fructose using D-psicose 3-epimerase (DPE) has been developed. However, the conversion yield is below 30%, which causes an undesirable increase of purification cost because of the similar solubility of D-psicose and D-fructose. Thus, we addressed the problem by converting the residual fructose, after the reaction of D-psicose production, to D-mannitol, which has a low solubility. The sequential whole cell conversion reactions for D-psicose and D-mannitol allow a convenient and economic purification of both products. This work was supported by a grant from the Next-Generation BioGreen 21 Program (SSAC, grant#: PJ01106201), RDA, Korea.
Reference
1) Carsten Bäumchen & Stephanie Bringer-Meyer (2007), Expression of glf Z.m. increases D-mannitol formation in whole cell biotransformation with resting cells of Corynebacterium glutamicum, Appl Microbiol Biotechnol 76(3):545–52.
2) Ortiz, M. E., Bleckwedel, J., Raya, R. R., & Mozzi, F. (2013). Biotechnological and in situ food production of polyols by lactic acid bacteria, Appl Microbiol Biotechnol 97:4713-4726
3) Park, Y., Oh, E. J., Jo, J., Jin, Y., & Seo, J. (2016). Recent advances in biological production of sugar alcohols. Curr Opin Biotechnol 37:105–113
CO-COMBUSTION OF KOREAN ANTHRACITE WITH VARIOUS FUELS IN A COMMERCIAL CIRCULATING FLUIDIZED BED BOILER
The effect of co-combustion of various fuels such as bituminous coal, imported anthracite, RDF and wood pellet with Korean anthracite on the combustion and environmental performance was observed in the commercial CFB boiler. The temperatures in the furnace and cyclones exits decreased with increasing the cocombustion ratio of the bituminous coal, which could achieve more stable operation of the CFB boiler. During Co-combustion of the RDF and wood pellets, the temperature of the furnace exit increased slightly with due to volatiles re-combustion which could restrict to increase the co-combustion ratio of the RDF and wood pellets in the CFB boiler. It was limited for the electrostatic precipitator (EP) to maintain the stable operation above 5% of the RDF co-combustion ratio according to decrease of the output voltages of the EP collecting plate. High content of CaO in the RDF and the wood pellet made the required limestone flow rates decrease. The emissions NOx, HCl and dioxin during co-combustion of the RDF and wood pellets did not change appreciably when compared with firing only Korean anthracite, which were also low enough to meet Korean regulation limits. On the other hand, chlorine content in the ashes emitted from the boiler increased gradually with increasing the RDF co-combustion ratio because of absorption by limestone. The co-combustion of various fuels with Korean anthracite in the commercial CFB boiler was found to be of great use up to a certain co-combustion ratio of each fuel without the technical and environmental problems
Multi-Agent Deep Reinforcement Learning for Efficient Passenger Delivery in Urban Air Mobility
It has been considered that urban air mobility (UAM), also known as
drone-taxi or electrical vertical takeoff and landing (eVTOL), will play a key
role in future transportation. By putting UAM into practical future
transportation, several benefits can be realized, i.e., (i) the total travel
time of passengers can be reduced compared to traditional transportation and
(ii) there is no environmental pollution and no special labor costs to operate
the system because electric batteries will be used in UAM system. However,
there are various dynamic and uncertain factors in the flight environment,
i.e., passenger sudden service requests, battery discharge, and collision among
UAMs. Therefore, this paper proposes a novel cooperative MADRL algorithm based
on centralized training and distributed execution (CTDE) concepts for reliable
and efficient passenger delivery in UAM networks. According to the performance
evaluation results, we confirm that the proposed algorithm outperforms other
existing algorithms in terms of the number of serviced passengers increase
(30%) and the waiting time per serviced passenger decrease (26%).Comment: 6 pages, 5 figure
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