Modeling and Analysis of Mobility Management in Mobile Communication Networks

Many strategies have been proposed to reduce the mobility management cost in mobile communication networks. This paper studies the zone-based registration methods that have been adopted by most mobile communication networks. We focus on two special zone-based registration methods, called two-zone registration (2Z) and two-zone registration with implicit registration by outgoing calls (2Zi). We provide a new mathematical model to analyze the exact performance of 2Z and 2Zi. We also present various numerical results, to compare the performance of 2Zi with those of 2Z and one-zone registration (1Z), and show that 2Zi is superior to 2Z as well as 1Z in most cases

Effect of extraction solvents on antioxidant and skin-whitening potentials of defatted Camellia seed cakes

Defatted Camellia japonica L. seed cake is an important byproduct during the manufacture of Camellia seed oil. The present study evaluated the influence of two extraction solvents on the total contents of phenol and flavonoid, antioxidant activity and skin-whitening effect capable of inhibiting the biosynthesis of melanin of defatted Camellia seed cakes, a byproduct from Camellia oil production. The antioxidant capacities of 100% methanol and 70% ethanol extracts were analysed using radical scavenging (1,1-diphenyl-2-picrylhydrazyl, O2-, H2O2 and NO), SOD-like, ferrous ion chelating and reducing power assays. The total phenolic and flavonoid contents were further determined by the Folin-Ciocalteu method. Moreover, intracellular antityrosinase activity and melanin contents were evaluated in human malignant melanoma cells (SK mel-100). Ethanol extracts of defatted Camellia seed cake extracts exhibited higher phenolic (4097 mg gallic acid equivalents/100 g) and flavonoid (2899 mg rutin equivalents/100 g) contents with higher superoxide (IC50 = 1.9 mg/mL), nitric oxide (IC50 =1.6 mg/mL) radical scavenging, ferrous ion chelating (IC50 = 2.9 mg/mL) and reducing power (IC50 = 1.8 mg/mL) activities than those of methanol. These ethanol extracts also evidenced more effective inhibitory activities of tyrosinase and melanin synthesis than methanol extracts. Therefore, the present results demonstrated that defatted Camellia seed cakes could be a valuable source of antioxidative and whitening ingredients, and ethanol was more efficient in extracting antioxidants and bioactive compounds than methanol

COMPARISON OF THE RISK FACTORS OF KOREAN ADOLESCENT SUICIDE RESIDING IN HIGH SUICIDAL REGIONS VERSUS THOSE IN LOW SUICIDAL REGIONS

Background: The suicide rate of the youth in South Korea has been increasing, and suicide of the youth still has been the most common cause of death since 2007. We aimed to determine the trends and the regional risk factors of youth suicide in South Korea from 2001 to 2010. Subjects and Methods: We used the data from the National Statistical Office to calculate the standardized suicide rates and various regional data including population census, employment, and labor. To calculate the effect of individual risk factors, we used the data from the fourth Korean Youth Risk Behavior Web-based Survey (KYRBWS-VI). Conditional autoregressive model for regional standardized mortality ratio (SMR) using inter-regional spatial information was fitted. Results: Suicide rates of adolescents aged 12 to 18 was from 3.5 per 100,000 people in 2001 and 5.3 per 100,000 in 2010. There were no significant gender difference in suicide rates, however, the number of suicides among adolescents aged 15-18 accounted for four times than those of adolescents ages 12-14. High proportion of late adolescents, higher number of recipients of national basic livelihood, and higher number of adolescents who treated with depression were related to elevated suicide rate of adolescent. Total sleep time of adolescents and regional unemployment rate were negatively associated with the suicide risk of respective regions. Conclusions: Age distribution, economic status, total sleep time, and the number of adolescent patients with depression were different between those in low and in high adolescent suicidal regions in Korea. Our findings suggest that preferential appliance of adolescent suicide prevention program for regions by considering those factors may be important steps to reduce adolescent suicide in Korea

Thermoelectric properties of nanoporous three-dimensional graphene networks

We propose three dimensional-graphene nanonetworks (3D-GN) with pores in the range of 10 similar to 20 nm as a potential candidate for thermoelectric materials. The 3D-GN has a low thermal conductivity of 0.90 W/mK @773 K and a maximum electrical conductivity of 6660 S/m @773 K. Our results suggest a straightforward way to individually control two interdependent parameters, sigma and kappa, in the nanoporous graphene structures to ultimately improve the figure of merit value.open

PPM1A Controls Diabetic Gene Programming through Directly Dephosphorylating PPAR?? at Ser273

Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a master regulator of adipose tissue biology. In obesity, phosphorylation of PPAR gamma at Ser273 (pSer273) by cyclin-dependent kinase 5 (CDK5)/extracellular signal-regulated kinase (ERK) orchestrates diabetic gene reprogramming via dysregulation of specific gene expression. Although many recent studies have focused on the development of non-classical agonist drugs that inhibit the phosphorylation of PPAR gamma at Ser273, the molecular mechanism of PPAR gamma dephosphorylation at Ser273 is not well characterized. Here, we report that protein phosphatase Mg2+/Mn2+-dependent 1A (PPM1A) is a novel PPAR gamma phosphatase that directly dephosphorylates Ser273 and restores diabetic gene expression which is dysregulated by pSer273. The expression of PPM1A significantly decreases in two models of insulin resistance: diet-induced obese (DIO) mice and db/db mice, in which it negatively correlates with pSer273. Transcriptomic analysis using microarray and genotype-tissue expression (GTEx) data in humans shows positive correlations between PPM1A and most of the genes that are dysregulated by pSer273. These findings suggest that PPM1A dephosphorylates PPAR gamma at Ser273 and represents a potential target for the treatment of obesity-linked metabolic disorders

Flightless-I Controls Fat Storage in Drosophila

Triglyceride homeostasis is a key process of normal development and is essential for the maintenance of energy metabolism. Dysregulation of this process leads to metabolic disorders such as obesity and hyperlipidemia. Here, we report a novel function of the Drosophila flightless-I (fliI) gene in lipid metabolism. Drosophila fliI mutants were resistant to starvation and showed increased levels of triglycerides in the fat body and intestine, whereas fliI overexpression decreased triglyceride levels. These flies suffered from metabolic stress indicated by increased levels of trehalose in hemolymph and enhanced phosphorylation of eukaryotic initiation factor 2 alpha (eIF2??). Moreover, upregulation of triglycerides via a knockdown of fliI was reversed by a knockdown of desat1 in the fat body of flies. These results indicate that fliI suppresses the expression of desat1, thereby inhibiting the development of obesity; fliI may, thus, serve as a novel therapeutic target in obesity and metabolic diseases

Dual Therapy with Cidofovir and Mirtazapine for Progressive Multifocal Leukoencephalopathy in a Sarcoidosis Patient

Background: Progressive multifocal leukoencephalopathy (PML) is a demyelinating central nervous system disease caused by JC virus (JCV) reactivation in immunocompromised patients. The disease course of PML is often progressive, fatal and at present, there are few reports on successful treatment outcomes. Case Report: A 45-year-old man with systemic sarcoidosis presented with rapidly progressive dementia and right hemiparesis. The patient was diagnosed with PML as confirmed via brain biopsy and JCV PCR. With a combination treatment of cidofovir and mirtazapine, there was significant improvement of neurological symptoms without measurable functional deficit. Conclusion: This case suggests that dual therapy with cidofovir and mirtazapine might be an effective treatment option in PML patients with sarcoidosis