• Journal of Communications and Networks
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• 제4권3호
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• pp.161-169
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• 2002

Ad hoc wireless networks involving large populations of scattered communication nodes will play a key role in the development of low power, high capacity, interactive, multimedia communication networks. Such networks must support arbitrary network connections and provide coverage anywhere and anytime. This paper partitions such arbitrarily connected network architectures into three distinct groups, identifies the associated dual network architectures and counts the number of network architectures assuming there exist N network nodes. Connectivity between network nodes is characterized as a random event. Defining the link availability P as the probability that two arbitrary network nodes in an ad hoc network are directly connected, the network connection probability $ \integral_n$(p) that any two network nodes will be directly or indirectly connected is derived. The network connection probability $ \integral_n$(p) is evaluated and graphically demonstrated as a function of p and N. It is shown that ad hoc wireless networks containing a large number of network nodes possesses the same network connectivity performance as does a fixed network, i.e., for p>0, $lim_{N\to\infty} Integral_n(p)$ = 1. Furthermore, by cooperating with fixed networks, the ad hoc network connection probability is used to derive the global network connection probability for hybrid networks. These probabilities serve to characterize network connectivity performance for users of wireless ad hoc and hybrid networks, e.g., IEEE 802.11, IEEE 802.15, IEEE 1394-95, ETSI BRAN HIPERLAN, Bluetooth, wireless ATM and the world wide web (WWW).

• Nutrition Research and Practice
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• 제6권5호
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• pp.429-435
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• 2012

Atopic dermatitis (AD) has become a serious epidemic in Korean children. We aimed to investigate the association between vitamin C, E and other nutrients, and serum total IgE/specific IgE levels in children with AD. A total of 119 children (0-24 mo) diagnosed with AD were recruited for this cross-sectional study from a medical center in Seoul. A 24 h recall was used to assess dietary intakes. Serum total and six food-allergen specific IgE levels were measured by CAP-FEIA. Serum vitamin E was also measured but only in 25 out of the total 119 participants. Multiple linear regression analysis was performed to estimate the coefficients between serum IgE levels and dietary intake as well as serum vitamin E. Serum vitamin E levels showed a significantly inverse association with serum total IgE and all specific IgE levels (P < 0.05). Fat intake was inversely related with specific-IgEs for egg whites, milk, buck wheat, soy, and peanuts (P < 0.05). Positive associations were found between carbohydrate (CHO) intake and total IgE and specific IgEs to egg whites, milk, soy, and peanuts (P < 0.05). Vitamin C, E and n-3/n-6 fatty acids were not related with serum total IgE and specific IgE levels except for the association between buck wheat and vitamin E. In addition, there were no significant differences between males and females in dietary intake and serum IgE levels by student's t-test. Although dietary vitamin E showed no association with serum IgE levels, serum vitamin E drew a significant inverse relationship with serum IgE levels. The evidence seems to suggest that vitamin E may possibly lower total and specific-IgEs in children with AD, and that it is important to maintain a relatively high serum vitamin E level in children with AD.

• 동서간호학연구지
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• 제20권1호
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• pp.57-62
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• 2014

Purpose: The purpose of this study was to evaluate the effect of a mixture of ARL oils, Agastache rugosa, Rosemarinu officinalis, and Lavandula angustifolia on atopic dermatitis (AD) model on NC/Nga mice. Methods: Twenty-four, 6 week-NC/Nga mice were assigned to a control group (C, n=8), an AD-induced group (E, n=8), and an ARL oil-treated group (E, n=8) that had two treatments per day for 6 days. Epidermis thickness, total amount of collagen and expression of TGF-${\beta}$ in the AD induced mice were measured. Results: The ARL oil-treated group showed a significantly decreased epidermis thickness, and a greater amount of collagen and expression of TGF-${\beta}$ compared with the AD-induced group. Conclusison: ARL oil may be a putative resources for care or treatment of AD in the view of nursing intervention.

• Natural Product Sciences
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• 제28권3호
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• pp.138-142
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• 2022

Alzheimer's disease (AD) is the most common age-related neurodegenerative disease in industrialized countries. It is estimated that about 47 million people living with dementia and the number of cases will be tripled by 2050. However, the exact mechanism of AD is not known, and full therapy has still not been found. Various tryptophan-derived alkaloids have been reported as promising agents for the treatment of AD. In the present study, a series of tryptophan-derived alkaloids were isolated and characterized from the methanol extract of Hedera rhombea fruit. Based on the analysis of their observed and reported spectroscopic data, their structures were identified as N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan (1), N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan (2), N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan methyl ester (3), and N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan methyl ester (4). These compounds were screened for anti-Alzheimer activity via their inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes in vitro. As a result, compounds 3 and 4 showed moderate BChE inhibition with IC₅₀ values of 86.9 and 78.4 μM, respectively, compared to those of the positive control [berberine (IC₅₀ = 11.5 μM)]. However, all four compounds did not show significant inhibition of the AChE enzyme. This is the first time, the AChE and BChE inhibitory activities of these tryptophan-derived alkaloids were investigated and reported.

• Journal of Communications and Networks
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• 제13권5호
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• pp.525-535
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• 2011

In this paper, we study the contribution of network coding (NC) in improving the multicast capacity of random wireless ad hoc networks when nodes are endowed with multi-packet transmission (MPT) and multi-packet reception (MPR) capabilities. We show that a per session throughput capacity of ${\Theta}$(nT$^3$(n)) can be achieved as a tight bound when each session contains a constant number of sinks where n is the total number of nodes and T(n) is the transmission range. Surprisingly, an identical order capacity can be achieved when nodes have only MPR and MPT capabilities. This result proves that NC does not contribute to the order capacity of multicast traffic in wireless ad hoc networks when MPR and MPT are used in the network. The result is in sharp contrast to the general belief (conjecture) that NC improves the order capacity of multicast. Furthermore, if the communication range is selected to guarantee the connectivity in the network, i.e., ${\Omega}$($\sqrt{log\;n/n}$)=T(n) = O(log log n / log n), then the combination of MPR and MPT achieves a throughput capacity of ${\Theta}$(log$^{\frac{3}{2}}$ n/$\sqrt{n}$) which provides an order capacity gain of ${\Theta}$(log$^2$ n) compared to the point-to-point multicast capacity with the same number of destinations.

• Journal of Nutrition and Health
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• 제38권7호
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• pp.521-532
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• 2005

The prevalence of atopic dermatitis (AD) continues to rise in industrialized countries related to Western lifestyle, including dietary habits, especially imbalance of intake of dietary fatty acids. The purpose of this study was to evaluate the dietary fatty acids and the assess the blood fatty acid composition and immune parameters in AD patients. AD (n = 50) patients and gender ${\cdot}$ age matched healthy controls (HC) were studied in case-control clinical trail. Current fatty acids intake status was determined by 3-day food record method. Blood sample were collected from 30 subjects in each group and blood fatty acid composition and immune parameters were analysed. AD patients consumed less PUFA and their n-6/n-3 PUFA ratio was higher than that of HC. Both the ratios of PUFA and MUFA were positively correlated with SCORAD in AD patients (p < 0.05). In the AD patients, there were abnormalities in the fatty acid composition of the RBC and WBC, SFA being significantly high and most n-3 PUFA being significantly low. Moreover, both the ratios of EPA and DHA in WBC were negatively correlated with dietary n-6/n-3 PUFA ratio in AD patients (p < 0.05). Serum total IgE and IL-4 levels of AD patients increased significantly compared with the levels of HC (p < 0.01). Ratios of monocyte and eosinophil in WBC of AD patients increased significantly compared with the levels of HC including total WBC count (p < 0.01), and ratios of Iymphocyte and basophil in WBC of AD patients decreased significantly compared with the levels of HC (p < 0.05). Moreover, the ratios of eosinophil in WBC were positively correlated with dietary P/M ratio (p < 0.05), and the ratios of monocyte in WBC were positively correlated with n-6/n-3 PUFA ratio (p < 0.05) in AD patients. This results indicated that AD patients had significantly high intake of dietary n-6/n-3 PUFA compared with HC. Imbalance of intake of dietary fatty acids affected fatty acid compositions in the RBC and WBC, and these lead to immune imbalance and grow worse of AD.

• Journal of Acupuncture Research
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• 제38권4호
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• pp.293-299
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• 2021

Background: This study sought to determine whether the antioxidant effects of astaxanthin (AST) could have an anti-inflammatory effect to reduce inflammation caused by atopic dermatitis (AD). Methods: Using a mouse model of AD induced by phtalic acid (PA), the levels of inflammation, inflammatory agents, and evidence of antioxidant activity were examined in PA treated mice (n = 3), PA-AST treated mice (n = 3), and a control group of mice (n = 3). This included measurements of ear thickness, levels of mast cells, IgE, inflammatory cytokine, malondialdehyde (MDA), hydrogen peroxide, HO-1, and GPx-1. Results: AST treatment significantly prevented inflammation as measured by ear thickness (p < 0.05), mast cell count (p < 0.001), and IgE concentration in the blood (p < 0.001). Levels of TNF-α (p < 0.001), IL-1β (p < 0.001), IL-6 (p < 0.001), and MDA (p < 0.05) were also significantly lower. In addition, GSH levels increased significantly (p < 0.001), and the level of hydrogen peroxide significantly reduced (p < 0.01). The expression of HO-1, GPx-1 increased. Conclusion: In this small experimental study, AST acted on inflammatory mechanisms that induced AD, through anti-inflammatory and antioxidant mechanisms, and is a candidate of interest in the clinical treatment of AD.

• 천문학회보
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• 제42권2호
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• pp.55.5-56
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• 2017

Galaxy dynamics probes weak gravity at accelerations below the de Sitter scale of acceleration adS = cH, where c is the velocity of light and H is the Hubble parameter. Low and high redshift galaxies hereby offer a novel probe of weak gravity in an evolving cosmology, satisfying H(z) = H0(1 + A(6z + 12z^2 +12z^3+ 6z^4+ (6/5)z^5)/(1 + z) with baryonic matter content A sans tension to H0 in surveys of the Local Universe. Galaxy rotation curves show anomalous galaxy dynamics in weak gravity aN < adS across a transition radius r beyond about 5 kpc for galaxy mass of 1e11 solar mass. where aN is the Newtonian acceleration based on baryonic matter content. We identify this behavior with a holographic origin of inertia from entanglement entropy, that introduces a C0 onset across aN=adS with asymptotic behavior described by a Milgrom parameter satisfying a0=omega/(2pi), where omega=sqrt(1-q)H is a fundamental eigenfrequency of the cosmological horizon. Extending an earlier confrontation with data covering 0.003 < aN/adS < 1 at redshift z about zero in Lellie et al. (2016), the modest anomalous behavior in the Genzel et al. sample at redshifts 0.854 < z <2.282 is found to be mostly due to clustering 0.36 < aN/adS < 1 close to the C0 onset to weak gravity and an increase of up to 65% in a0.

• Asian Journal of Atmospheric Environment
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• 제10권2호
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• pp.114-123
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• 2016

A change in chemical compositions of Asian dust (AD) particles can dramatically alter their optical properties, cloud-forming properties, and health effects. The present study was undertaken to evaluate this aging of AD particles by means of two complementary methods (i.e., the traditional spot test and the most advanced micro-PIXE analytical technique) for single particle analysis. Size-classified particles were sampled at the rural peninsula of Korea (Byunsan, 35.37N; 126.27E) during AD event and non-AD period in 2004. Sulfate was principally enriched on the particles in the size range of $7.65-10.85{\mu}m$ collected during AD event. The average number fraction of coarse particles ($>2.05{\mu}m$) containing chloride was 16.2% during AD event. Relatively low particles containing nitrate compared to those containing sulfate and chloride were found in AD event. Micro-PIXE elemental maps indicated that a large number of AD particles were internally mixed with man-made zinc. The highest peaks of EC and OC concentrations were appeared at $0.01-0.43{\mu}m$ particle aerodynamic diameter. High EC concentration in $PM_1$ was might be caused by the Saemangeum Seawall Project that was being conducted during our field measurement.

• 대한화학회지
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• 제39권8호
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• pp.650-656
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• 1995

25$^{\circ}C$의 50%(v/v) 메탄올-물의 혼합용매 속에서 N-(benzenesulfonyl)-C-(N-methylanilino)imidoyl Chloride 유토체의 가수분해 반응 속도 상수를 자외선 분광광도법으로 측정하여 반응속도식, 치환기효과, 용매효과, 염효과, 열역학적 할성화 파라미터 및 가수분해 생성물의 분석 등의 결과로부터 pH9.0 이하의 범위에서는 azocarbonium ion 중간체를 지나는 $S_N1$형 반응, pH 10.0 이상의 pH에서는 사면체 중간체를 지나는 친핵성 첨가-제거반응($Ad_{N-E}$)이 일어남을 제안하였다.