Daejeon University

About: Daejeon University is a education organization based out in Daejeon, South Korea. It is known for research contribution in the topics: Acupuncture & Randomized controlled trial. The organization has 1540 authors who have published 2386 publications receiving 29677 citations.

On the general BER expression of one- and two-dimensional amplitude modulations

Abstract: Quadrature amplitude modulation (QAM) is an attractive technique to achieve high rate transmission without increasing the bandwidth. A great deal of attention has been devoted to the study of bit error rate (BER) performance of QAM, and approximate expressions for the bit error probability of QAM have been developed in many places in the literature. However, the exact and general BER expression of QAM with an arbitrary constellation size has not been derived yet. We provide an exact and general closed-form expression of the BER for one-dimensional and two-dimensional amplitude modulations, i.e., PAM and QAM, under an additive white Gaussian noise (AWGN) channel when Gray code bit mapping is employed. The provided BER expressions offer a convenient way to evaluate the performance of PAM and QAM systems for various cases of practical interest. Moreover, simple approximations can be found from our expressions, which are the same as the well-known approximations, if only the dominant terms are considered.

Reactive Oxygen Species, Aging, and Antioxidative Nutraceuticals.

Abstract: The important roles of reactive oxygen species in diseases related to aging and the necessity and benefits of antioxidative nutraceuticals in the prevention of diseases and promotion of healthy aging have been extensively reported in recent years Oxygen is an essential component of living organisms The generation of reactive oxygen species such as superoxide anion, hydrogen peroxide, hydroxyl radicals, and singlet oxygen is inevitable in aerobic metabolism of the body Reactive oxygen species cause lipid oxidation, protein oxidation, DNA strand break and base modification, and modulation of gene expression In the past several years, unprecedented progress has been made in the recognition and understanding of roles of reactive oxygen species in many diseases These include atherosclerosis, vasospasms, cancers, trauma, stroke, asthma, hyperoxia, arthritis, heart attack, age pigments, dermatitis, cataractogenesis, retinal damage, hepatitis, liver injury, and periodontis, which are age-related The body protects itself from the potential damages of reactive oxygen species Its first line of defense is superoxide dismutases, glutathione peroxidases, and catalase Scientists have indicated that antioxidant nutraceuticals supplied from daily diets quench the reactive oxygen species or are required as cofactors for antioxidant enzymes Nutraceuticals play significant roles in the prevention of a number of age-related diseases and are essential for healthy aging Epidemiological studies also reported the relevance of antioxidative nutraceuticals to health issues and the prevention of age-related diseases Health-conscious consumers have made antioxidative nutraceuticals the leading trend in the food industry worldwide in recent years

Reduced striatal dopamine D2 receptors in people with Internet addiction.

Abstract: An increasing amount of research has suggested that Internet addiction is associated with abnormalities in the dopaminergic brain system. We hypothesized that Internet addiction would be associated with reduced levels of dopaminergic receptor availability in the striatum compared with controls. To test this hypothesis, a radiolabeled ligand [ 11 C]raclopride and positron emission tomography was used to assess dopamine D2 receptor binding potential in men with and without Internet addiction. Consistent with our prediction, individuals with Internet addiction showed reduced levels of dopamine D2 receptor availability in subdivisions of the striatum including the bilateral dorsal caudate and right putamen. This finding contributes to the understanding of neurobiological mechanism of Internet addiction.