An extension to the Brun-Titchmarsh theorem

The Siegel-Walfisz theorem states that for any B > 0, we have ∑/p≤x/p≡a(mod k) 1 ∼ x/φ(k) lox x for k ≤ log B x and (k, a) = 1. This only gives an asymptotic formula for the number of primes over an arithmetic progression for quite small moduli k compared with x. However, if we are only concerned about upper bound, we have the Brun-Titchmarsh theorem, namely for any 1 ≤ k 0, s ≥ 1 and 1 ≤ k < x.In particular, for s ≤ log log (x/k), we have ∑/y<n≤x+y ≡ a (mod k)ω (n) < s 1 ≪ x/φ (k) log (x/k) (log log (x/k) + K)s-1/(s-1)! √ log log (x/k) + K and for any ε∈(0, 1) and s ≤ (1-ε) log log (x/k), we have. ∑/y<n≤x+y ≡ a (mod k)ω (n) < s 1 ≪ ε-1x/φ (k) log (x/k) (log log (x/k) +K)s-1/(s-1) !. © 2010. Published by Oxford University Press. All rights reserved.postprin

IG-WRDRR Report 2010: Hong Kong

Reports on WRDRR activities in Asia-Pacific region (Part 1)This report gives an account of the wind conditions in Hong Kong and the corresponding wind related damages in Hong Kong throughout the years. Details are presented in the report under three different aspects. First, typhoon wind and related damages; second, thunderstorm wind and related damages; and third, flooding related to wind storms and damages. Measures taken by the Hong Kong Government to reduce the risk of damages and disaster mitigation are also presented.postprin

An Outlook Add-in for managing of users' circulation records

HKU Libraries has created this new Outlook add-in to automatically update your Outlook Calendar with HKUL events, Circulation due dates and pickup dates. Please note that Outlook has long had the ability to hotsync and update calendars in portable devices such as Palm, PocketPC, Smartphone, and iPod. Therefore, once this new add-in is installed in Outlook, and if hotsyncing is set up on your PC, HKUL dates will also appear in the calendars of your portable devices.published_or_final_versio

Optical characteristics of GAN/SI micro-pixel light-emitting diode arrays

Two-dimensional arrays of emissive micro-light-emitting diodes (μ-LEDS) have been developed for a variety of applications such as high resolution micro-displays, maskless photo-lithography and multichannel visible-light optical communications amongst others. μ-LEDs have traditionally been fabricated on InGaN LED wafers grown on transparent sapphire substrates, and have suffered from optical crosstalk issues. When a single pixel is addressed, adjacent pixels and regions appear illuminated simultaneously. Such problems could result in functional failure in high-density μ-LED applications, including reduced resolution of micro-display and decreased signal-to-noise ratio in ...postprin

Impact of visceral fat on skeletal muscle mass and vice versa in a prospective cohort study: The Korean Sarcopenic Obesity Study (KSOS)

Objectives: Sarcopenia and visceral obesity have been suggested to aggravate each other, resulting in a vicious cycle. However, evidence based on prospective study is very limited. Our purpose was to investigate whether visceral fat promotes a decrease in skeletal muscle mass and vice versa. Methods: We observed changes in anthropometric and body composition data during a follow-up period of 27.6±2.8 months in 379 Korean men and women (mean age 51.9±14.6 years) from the Korean Sarcopenic Obesity Study (KSOS). Appendicular lean soft tissue (ALST) mass was calculated using dual-energy X-ray absorptiometry, and visceral fat area (VFA) was measured using computed tomography at baseline and follow-up examination. Results: ALST mass significantly decreased, whereas trunk and total fat mass increased in both men and women despite no significant change in weight and body mass index. In particular, women with visceral obesity at baseline had a greater decrease in ALST mass than those without visceral obesity (P=0.001). In multiple linear regression analysis, baseline VFA was an independent negative predictor of the changes in ALST after adjusting for confounding factors including age, gender, life style and body composition parameters, insulin resistance, high sensitivity C-reactive protein and vitamin D levels (P=0.001), whereas the association between baseline ALST mass and changes in VFA was not statistically significant (P=0.555). Conclusions: This longitudinal study showed that visceral obesity was associated with future loss of skeletal muscle mass in Korean adults. These results may provide novel insight into sarcopenic obesity in an aging society

Reduced cytotoxicity of insulin-immobilized CdS quantum dots using PEG as a spacer

Cytotoxicity is a severe problem for cadmium sulfide nanoparticles (CSNPs) in biological systems. In this study, mercaptoacetic acid-coated CSNPs, typical semiconductor Q-dots, were synthesized in aqueous medium by the arrested precipitation method. Then, amino-terminated polyethylene glycol (PEG) was conjugated to the surface of CSNPs (PCSNPs) in order to introduce amino groups to the surface. Finally, insulin was immobilized on the surface of PCSNPs (ICSNPs) to reduce cytotoxicity as well as to enhance cell compatibility. The presence of insulin on the surface of ICSNPs was confirmed by observing infrared absorptions of amide I and II. The mean diameter of ICSNPs as determined by dynamic light scattering was about 38 nm. Human fibroblasts were cultured in the absence and presence of cadmium sulfide nanoparticles to evaluate cytotoxicity and cell compatibility. The results showed that the cytotoxicity of insulin-immobilized cadmium sulfide nanoparticles was significantly suppressed by usage of PEG as a spacer. In addition, cell proliferation was highly facilitated by the addition of ICSNPs. The ICSNPs used in this study will be potentials to be used in bio-imaging applications

C5 Extract Induces Apoptosis in B16F10 Murine Melanoma Cells through Extrinsic and Intrinsic Apoptotic Pathways and Sub-G1 Phase Arrest

Purpose: To investigate the anti-cancer activities of C5 extract (C5E), a new herbal preparation from Korea, on B16F10 cells.Methods: The anti-proliferative effects of C5E were assessed by culturing B16F10 cells in the presence or absence of C5E. Cell cycle progression was analyzed by PI staining using flow cytometry. The quantities of apoptosis-inducing proteins were measured by Western blot.Results: C5E inhibited the proliferation of B16F10 cells but not human keratinocytes. C5E induced S phase arrest by interfering with cell regulatory factors such as cyclins B1, D1, D3, and E, and cyclindependent kinase 2, in B16F10 cells. Furthermore, immunoblot analysis confirmed that treatment with C5E induced apoptosis and cleaved caspase-3, poly (ADP-ribose) polymerase, via extrinsic pathway, whereas Bcl-2 expression was down-regulated. In addition, the suppression of cell proliferation by C5E is through down-regulation of p-Akt, up-regulation of phosphatase and tensin homolog protein expression via phosphoinositol 3 kinase survival signaling pathways in B16F10 cells. The combined cytotoxic effects of C5E and vinblastine generated 10 % increase in activity in contrast to the sum of the inhibitory effects of the individual agents.Conclusion: C5E shows promising anti-cancer activity and can be a useful adjuvant with vinblastine in combination therapeutic treatment of skin cancer.Keywords: Melanoma, Apoptosis, Anti-cancer, p53, Vinblastine, Cell cycle arrest, Caspas

Investigating poultry trade patterns to guide avian influenza surveillance and control: a case study in Vietnam

Live bird markets are often the focus of surveillance activities monitoring avian influenza viruses (AIV) circulating in poultry. However, in order to ensure a high sensitivity of virus detection and effectiveness of management actions, poultry management practices features influencing AIV dynamics need to be accounted for in the design of surveillance programmes. In order to address this knowledge gap, a cross-sectional survey was conducted through interviews with 791 traders in 18 Vietnamese live bird markets. Markets greatly differed according to the sources from which poultry was obtained, and their connections to other markets through the movements of their traders. These features, which could be informed based on indicators that are easy to measure, suggest that markets could be used as sentinels for monitoring virus strains circulating in specific segments of the poultry production sector. AIV spread within markets was modelled. Due to the high turn-over of poultry, viral amplification was likely to be minimal in most of the largest markets. However, due to the large number of birds being introduced each day, and challenges related to cleaning and disinfection, environmental accumulation of viruses at markets may take place, posing a threat to the poultry production sector and to public health