1,272 research outputs found
Night-sky brightness monitoring in Hong Kong A city-wide light pollution assessment
Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light-sensing device called the Sky QualityMeter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong is severe - the urban night skies (sky brightness at 15.0 mag arcsec -2) are on average ~ 100 times brighter than at the darkest rural sites (20.1 mag arcsec -2), indicating that the high lighting densities in the densely populated residential and commercial areas lead to light pollution. In the worst polluted urban location studied, the night-sky at 13.2 mag arcsec -2 can be over 500 times brighter than the darkest sites in Hong Kong. The observed night-sky brightness is found to be affected by human factors such as land utilization and population density of the observation sites, together with meteorological and/or environmental factors. Moreover, earlier night skies (at 9:30 p.m. local time) are generally brighter than later time (at 11:30 p.m.), which can be attributed to some public and commercial lightings being turned off later at night. On the other hand, no concrete relationship between the observed sky brightness and air pollutant concentrations could be established with the limited survey sampling. Results from this survey will serve as an important database for the public to assess whether new rules and regulations are necessary to control the use of outdoor lightings in Hong Kong. © Springer Science+Business Media B.V. 2011.published_or_final_versionSpringer Open Choice, 21 Feb 201
Quad-level bit-stream signal processing on FPGAs
Quad-level bit-stream signal processing (BSSP) circuits are implemented and their performances are compared with previously published tri-level and bi-level BSSP implementations on FPGAs. BSSP refers to the process of performing computation directly on over-sampled delta-sigma modulated signals to eliminate the need of resource consuming decimators and interpolators. Quad-level BSSP offers better performance than their bi-and tri-level counterparts at the expense of higher resource utilization. Using a digital phase locked loop (DPLL) and a quadrature phase-shift keying (QPSK) demodulator as application examples, the effectiveness of quad-level BSSP on FPGAs is studied. The BSSP approach will be contrasted with conventional multi-bit implementations using built-in digital signal processing blocks in modern FPGAs. © 2008 IEEE.published_or_final_versionThe IEEE International Conference on ICECE Technology (FPT 2008), Taipei, Taiwan, 8-10 December 2008. In Proceedings of ICFPT, 2008, p. 309-31
Quad-level bit-stream signal processing on FPGAs
Quad-level bit-stream signal processing (BSSP) circuits are implemented and their performances are compared with previously published tri-level and bi-level BSSP implementations on FPGAs. BSSP refers to the process of performing computation directly on over-sampled delta-sigma modulated signals to eliminate the need of resource consuming decimators and interpolators. Quad-level BSSP offers better performance than their bi-and tri-level counterparts at the expense of higher resource utilization. Using a digital phase locked loop (DPLL) and a quadrature phase-shift keying (QPSK) demodulator as application examples, the effectiveness of quad-level BSSP on FPGAs is studied. The BSSP approach will be contrasted with conventional multi-bit implementations using built-in digital signal processing blocks in modern FPGAs. © 2008 IEEE.published_or_final_versionThe IEEE International Conference on ICECE Technology (FPT 2008), Taipei, Taiwan, 8-10 December 2008. In Proceedings of ICFPT, 2008, p. 309-31
Identification and characterization of EBP, a novel EEN binding protein that inhibits Ras signaling and is recruited into the nucleus by the MLL-EEN fusion protein
The chimeric MLL-EEN fusion protein is created as a result of chromosomal translocation t(11;19)(q23;p13). EEN, an Src homology 3 (SH3) domain-containing protein in the endophilin family, has been implicated in endocytosis, although little is known about its role in leukemogenesis mediated by the MLL-EEN fusion protein. In this study, we have identified and characterized EBP, a novel EEN binding protein that interacts with the SH3 domain of EEN through a proline-rich motif PPERP. EBP is a ubiquitous protein that is normally expressed in the cytoplasm but is recruited to the nucleus by MLL-EEN with a punctate localization pattern characteristic of the MLL chimeric proteins. EBP interacts simultaneously with EEN and Sos, a guanine-nucleotide exchange factor for Ras. Coexpressoin of EBP with EEN leads to suppression of Ras-induced cellular transformation and Ras-mediated activation of Elk-1. Taken together, our findings suggest a new mechanism for MLL-EEN-mediated leukemogenesis in which MLL-EEN interferes with the Ras-suppressing activities of EBP through direct interaction. © 2004 by The American Society of Hematology.postprin
Family violence accounts for 25% of homicides in Hong Kong
Letters to the editorpublished_or_final_versio
A randomized controlled trial of qigong exercise on fatigue symptoms, functioning, and telomerase activity in persons with chronic fatigue or chronic fatigue syndrome
BACKGROUND: Chronic fatigue is common in the general population. Complementary therapies are often used by patients with chronic fatigue or chronic fatigue syndrome to manage their symptoms. PURPOSE: This study aimed to assess the effect of a 4-month qigong intervention program among patients with chronic fatigue or chronic fatigue syndrome. METHODS: Sixty-four participants were randomly assigned to either an intervention group or a wait list control group. Outcome measures included fatigue symptoms, physical functioning, mental functioning, and telomerase activity. RESULTS: Fatigue symptoms and mental functioning were significantly improved in the qigong group compared to controls. Telomerase activity increased in the qigong group from 0.102 to 0.178 arbitrary units (p < 0.05). The change was statistically significant when compared to the control group (p < 0.05). CONCLUSION: Qigong exercise may be used as an alternative and complementary therapy or rehabilitative program for chronic fatigue and chronic fatigue syndrome.published_or_final_versio
A comparison of intimate partner violence and associated physical injuries between cohabitating and married women: a 5-year medical chart review
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Copy number gain of granulin-epithelin precursor (GEP) at chromosome 17q21 associates with overexpression in human liver cancer
Background: Granulin-epithelin precursor (GEP), a secretory growth factor, demonstrated overexpression in various human cancers, however, mechanism remain elusive. Primary liver cancer, hepatocellular carcinoma (HCC), ranks the second in cancer-related death globally. GEP controlled growth, invasion, metastasis and chemo-resistance in liver cancer. Noted that GEP gene locates at 17q21 and the region has been frequently reported to be amplified in subset of HCC. The study aims to investigate if copy number gain would associate with GEP overexpression. Methods: Quantitative Microsatellite Analysis (QuMA) was used to quantify the GEP DNA copy number, and fluorescent in situ hybridization (FISH) was performed to consolidate the amplification status. GEP gene copy number, mRNA expression level and clinico-pathological features were analyzed. Results: GEP DNA copy number determined by QuMA corroborated well with the FISH data, and the gene copy number correlated with the expression levels (n = 60, r = 0.331, P = 0.010). Gain of GEP copy number was observed in 20% (12/60) HCC and associated with hepatitis B virus infection status (P = 0.015). In HCC with increased GEP copy number, tight association between GEP DNA and mRNA levels were observed (n = 12, r = 0.664, P = 0.019). Conclusions: Gain of the GEP gene copy number was observed in 20% HCC and the frequency comparable to literatures reported on the chromosome region 17q. Increased gene copy number contributed to GEP overexpression in subset of HCC. © Yung et al; licensee BioMed Central.published_or_final_versio
The molecular mechanism of the anti-oxidative effects of catechin on palmitic acid-induced cytotoxicity in astrocytes
Poster PresentationAIMS: Metabolic syndrome (MS) encompasses a group of problems which will put a person at a high risk of developing cardiovascular diseases, including heart attack and stroke. Effective prevention or treatment of MS significantly reduces the risk for developing serious complications. Palmitic acid (PA) is a saturated fatty acid, when being excessive, is a significant risk factor for development of MS or stroke. However, damage by MS to astrocytes is relatively unexplored. Catechin is an effective antioxidant which would be beneficial to neurons subjected to reactive oxygen species (ROS) damage as well ...postprin
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