Air quality as a public health problem in Hong Kong: measuring the risks

Hong Kong has an air quality problem with excess levels of such air pollutants as sulphur dioxide, nitrogen oxides, particulates and ozone, occurring from time to time throughout the year. This paper outlines the sources of the major pollutants in Hong Kong, both natural and manmade, and examines the health risks to the Hong Kong population from exposure to such pollutants. The principle man-made sources of these pollutants are mainly diesel vehicle emissions, and high sulphur content fuels burnt in industrial furnaces and power plants. There is concern over levels of these pollutants in ambient air because of their relationship with respiratory health problems, which range from local irritation of the respiratory tract to carcinogenesis. Studies in Hong Kong also demonstrate the importance of environmental tobacco smoke in the home as a cause of children's respiratory health problems, in addition to poor air quality. Epidemiological studies are useful tools for identifying risks and for evaluating the effectiveness of preventive measures, including legislation. In particular we need to identify health risks to young children and the preventable fraction likely to be achieved from different interventions. For optimum effectiveness, a multisectoral approach, developed between regulatory agencies, pubic health authorities and research groups, is needed to contribute to the overall respiratory health of the community.published_or_final_versio

Cortical State Fluctuations during Sensory Decision Making

In many behavioral tasks, cortex enters a desynchronized state where low-frequency fluctuations in population activity are suppressed. The precise behavioral correlates of desynchronization and its global organization are unclear. One hypothesis holds that desynchronization enhances stimulus coding in the relevant sensory cortex. Another hypothesis holds that desynchronization reflects global arousal, such as task engagement. Here, we trained mice on tasks where task engagement could be distinguished from sensory accuracy. Using widefield calcium imaging, we found that performance-related desynchronization was global and correlated better with engagement than with accuracy. Consistent with this link between desynchronization and engagement, rewards had a long-lasting desynchronizing effect. To determine whether engagement-related state changes depended on the relevant sensory modality, we trained mice on visual and auditory tasks and found that in both cases desynchronization was global, including regions such as somatomotor cortex. We conclude that variations in low-frequency fluctuations are predominately global and related to task engagement

Proceedings of the ASAIHL Seminar on the Role of the ASAIHL in Combating Health Hazards of Environmental Pollution: June 17-20, 1992, University of Hong Kong

Includes bibliographical references.Sponsored by the ASAIHLpublished_or_final_versionLegal controls of environmental pollution in Asia: how effective are they? Allen, J. Allen, J. 256Hong Kong's water pollution controls: are we serious? Baillie, B.G. Baillie, B.G. 265Environmental law in Hong Kong - a legal practitioner's point of view Skrine, R. Skrine, R. 277Has the use of unleaded petrol provided a lead-free environment in Hong Kong? Au, C.T. Au, C.T. Chou, K.M. Chou, K.M. Wong, K.Y. Wong, K.Y. 282The influence of the health act on present environmental problems Prabawa Utama, S.H. Prabawa Utama, S.H. 288Characteristics of acid rain in mainland China Hong, Y.T. Hong, Y.T. 42Environmental impact assessment and the role of legislation in environmental control - the case of Malaysia Idris, A.B. Idris, A.B. Fuad, A. Fuad, A. 294Social responsbility awareness assessment of selected university respondents in combating environmental pollution Barcelona, A.C. Barcelona, A.C. 301Alternatives to legal controls on environmental pollution Kaine, G. Kaine, G. Reeve, I. Reeve, I. Musgrave, W. Musgrave, W. 306Introduction 315Towards low-waste technology Diaper, J. Diaper, J. 317Changing environmental values and institution building: the role of ASAIHL Hills, P. Hills, P. 325The nature and control of motor vehicle emissions - methanol as an alternative fuel Cheung, C.S. Cheung, C.S. Lui, Y.B. Lui, Y.B. Leung, T.P. Leung, T.P. 335Prevention and treatment of environmental pollution Mena, M.M. Mena, M.M. 332Treatment and disposal of heavy metal wastes using cementitious solidification Peralta, G.L. Peralta, G.L. Ballesteros, F.C. Ballesteros, F.C. Cepeda, M.L. Cepeda, M.L. 340A membrane anaerobic system for wastewater treatment Fakrul-Razi, A. Fakrul-Razi, A. 346Prevention and treatment of air pollution in Hong Kong Lam, J.C. Lam, J.C. 351Environmental education - a strategy for the treatment and prevention of environmental pollution Manalo, J.A. Manalo, J.A. Sergovia, V. Sergovia, V. Hocson, T.R. Hocson, T.R. 357Bacterial reduction during sewage treatment - the Hong Kong experience Hodgkiss, I.J. Hodgkiss, I.J. Chiu, S.H.C. Chiu, S.H.C. 360Treatment and prevention of environmental pollution in the Philippines De Jesus, E.M. De Jesus, E.M. 366Microbiological study of shellfish and water quality in Deep Bay, Hong Kong Kueh, C.S.W. Kueh, C.S.W. 369Environmental deterioration in greater Bangkok, Thailand Paraken, Y. Paraken, Y. 376The 'polluter pays' principle: the distribution of economic impacts Rahim, K.A. Rahim, K.A. 378The role of Philippine ASAIHL institutions in combating the hazards of environmental pollution in Manila Quirino, T.U. Quirino, T.U. 35Education programmes for training of agrichemical users in New Zealand Penman, D.R. Penman, D.R. 31The role of institutions of higher learning in combating health hazards of environmental pollution Rampal, K.G. Rampal, K.G. Ismail, N. Ismail, N. 26The contribution of health care departments in tertiary institutions in Hong Kong to combating the hazards of pollution King, A.R. King, A.R. 19Australian approaches to finger printing sources of environmental lead with isotopes Gulson, B.L. Gulson, B.L. 13D Treatment and prevention of environmental pollutionC Legal controls of environmental pollutionB Monitoring and instrumentation of environmental pollutionA Health hazards of environmental pollutionCountry reportsKeynote address Wang, Gungwu Wang, Gungwu 2Impact of industry on the health of surrounding communities: an analysis of epidemiological and public health challenges Bhopal, R.S. Bhopal, R.S. 65Epidemiology and environmental health: reliable risk measurement in well-populations Lam, T.H. Lam, T.H. Hedley, A.J. Hedley, A.J. Peters, J. Peters, J. 74An investigation into the presence of anaerobic bacteria in coastal waters of Hong Kong Boost, M.V. Boost, M.V. Wong, L.P. Wong, L.P. Wong, P.S. Wong, P.S. Ma, K.C. Ma, K.C. 82Pollutions within the built environment Burnett, J. Burnett, J. Chan, D.W.T. Chan, D.W.T. 87The effects of pesticides use on the health of on farmers in East Java, Indonesia Mukono, J. Mukono, J. 94Noise and human activities in Hong Kong: a review Tan, T.C. Tan, T.C. Wong, L.T.L. Wong, L.T.L. 98Analysis of organophosphorus insecticides in vegetables Tanner, P.A. Tanner, P.A. Leung, K.H. Leung, K.H. 105Health risk and environmental pollution: the hidden factors Peters, J. Peters, J. Lui, J. Lui, J. Wong, C.M. Wong, C.M. Hedley, A.J. Hedley, A.J. Lam, T.H. Lam, T.H. Ong, S.G. Ong, S.G. Tam, A.Y.C. Tam, A.Y.C. 109Risk assessment and management in the prevention of adverse effects on human health and the environment Spickett, J.T. Spickett, J.T. 117Indoor and outdoor pollution in shops and offices in Hong Kong and health effects Bacon-Shone, J. Bacon-Shone, J. Liao, S. Liao, S. 122Climatological assessment of potential heat stress in Hong Kong Kyle, W.J. Kyle, W.J. 126Asbestos dust: a silent enemy Lam, K.Y. Lam, K.Y. 131Integrating environmental health problems into urban planning: problems in the Asian-Pacific region and the challenges for universities Simpson, R.W. Simpson, R.W. 134Organic solvent exposure in some manufacturing industries in Malaysia Tan, G.L.E. Tan, G.L.E. 138Introduction 145Introductino 63Monitoring and instrumentation of environmental pollution Tebbutt, T.H.Y. Tebbutt, T.H.Y. 145The air quality monitoring programme of the Hong Kong environmental protection department Leung, R.T.M. Leung, R.T.M. 152Low technology sampling can show spatial and temporal patterns of airborne metal pollution Lloyd, O.L. Lloyd, O.L. Fay, Gailey Fay, Gailey 159Heavy metal contamination in coastal waters - a case study of the north coast of Central Java, Indonesia Supriharyono Supriharyono 165Determination of phosphorus in natural water at parts per trillion level by laser thermal lens effect Wu, L. Wu, L. Siu, G.G. Siu, G.G. Chiu, D.D.S. Chiu, D.D.S. Stokes, M.J. Stokes, M.J. 171A geographical approach to evaluating the human impact upon water quality Peart, M.R. Peart, M.R. 178Modular auto-enrichment subsystem for use in environmental high pressure liquid chromatography analysis Chen, S.C. Chen, S.C. Chang, J.Y. Chang, J.Y. Wang, R.K. Wang, R.K. 183Exposure to environmental pollutants in the work environment: a case study of a traffic toll booth in Malaysia Yaziz, M.I. Yaziz, M.I. 187A proposed air quality index in Hong Kong Ng, C.N. Ng, C.N. Tanner, P.A. Tanner, P.A. 191Background level of trace elements in soils of mainland China Chen, J.S. Chen, J.S. Tao, S. Tao, S. Deng, B.S. Deng, B.S. Wang, X.J. Wang, X.J. 196Indoor monitoring of nitrogen oxides Cheung, M.T. Cheung, M.T. 200The role of Thai universities in combating health hazards of environmental pollution Wangsuphachart, V.L. Wangsuphachart, V.L. 54Development of a piezoelectric crystal sorption detector for continuous monitoring of organic vapours at the workplace Fung, Y.S. Fung, Y.S. 205Effects of some standard fixatives on fish gill morphology Shepherd, M. Shepherd, M. Ivanstoff, W. Ivanstoff, W. 210Improving the total environmental of Singapore Tan, T.C. Tan, T.C. 46Simulation of urban traffic noise on the environment Pamanikabud, P. Pamanikabud, P. 215Investigation into the haze episodes in the Kelang Valley, Malaysia Samah, A.A. Samah, A.A. 221Photoacoustic determination of organic pollutant gases in Hong Kong air Shi, B. Shi, B. Siu, G.G. Siu, G.G. Chiu, D.D.S. Chiu, D.D.S. 228Application of the proton induced X-ray emission (PIXE) technique for the study of respirable suspended particulated (RSP) in Hong Kong Cai, Z.X. Cai, Z.X. Sze, P.Y.K. Sze, P.Y.K. Stokes, M.J. Stokes, M.J. Young, E.C.M. Young, E.C.M. 234Follow-up stream sediment geochemical reconnaissance surveys in the vicinity of Tai Mo Shan, New Territories, Hong Kong Yim, W.W.S. Yim, W.W.S. Ng, C.Y. Ng, C.Y. Thornton, I. Thornton, I. 240Introduction 249Environmental pollution, higher education, and the rule of law Axline, M. Axline, M. 25

The essential genome of Streptococcus agalactiae.

BACKGROUND: Next-generation sequencing of transposon-genome junctions from a saturated bacterial mutant library (Tn-seq) is a powerful tool that permits genome-wide determination of the contribution of genes to fitness of the organism under a wide range of experimental conditions. We report development, testing, and results from a Tn-seq system for use in Streptococcus agalactiae (group B Streptococcus; GBS), an important cause of neonatal sepsis. METHODS: Our method uses a Himar1 mini-transposon that inserts at genomic TA dinucleotide sites, delivered to GBS on a temperature-sensitive plasmid that is subsequently cured from the bacterial population. In order to establish the GBS essential genome, we performed Tn-seq on DNA collected from three independent mutant libraries-with at least 135,000 mutants per library-at serial 24 h time points after outgrowth in rich media. RESULTS: After statistical analysis of transposon insertion density and distribution, we identified 13.5 % of genes as essential and 1.2 % as critical, with high levels of reproducibility. Essential and critical genes are enriched for fundamental cellular housekeeping functions, such as acyl-tRNA biosynthesis, nucleotide metabolism, and glycolysis. We further validated our system by comparing fitness assignments of homologous genes in GBS and a close bacterial relative, Streptococcus pyogenes, which demonstrated 93 % concordance. Finally, we used our fitness assignments to identify signal transduction pathway components predicted to be essential or critical in GBS. CONCLUSIONS: We believe that our baseline fitness assignments will be a valuable tool for GBS researchers and that our system has the potential to reveal key pathogenesis gene networks and potential therapeutic/preventative targets.This work was supported by NIH/NIAID R01 AI092743, R33 AI098654, and R21 AI11020 to A.J.R.; NIH/NICHD K23 HD065844 to T.M.R.; John M. Driscoll, Jr., M.D. Children’s Fund (Columbia University Department of Pediatrics) and the Pediatric Scientist Development Program (NIH/NICHD K12 HD000850) to T.A.H

Tools for analyzing parallel I/O

Parallel application I/O performance often does not meet user expectations. Additionally, slight access pattern modifications may lead to significant changes in performance due to complex interactions between hardware and software. These issues call for sophisticated tools to capture, analyze, understand, and tune application I/O. In this paper, we highlight advances in monitoring tools to help address these issues. We also describe best practices, identify issues in measure- ment and analysis, and provide practical approaches to translate parallel I/O analysis into actionable outcomes for users, facility operators, and researchers

Aberrant Cortical Activity In Multiple GCaMP6-Expressing Transgenic Mouse Lines

Transgenic mouse lines are invaluable tools for neuroscience but as with any technique, care must be taken to ensure that the tool itself does not unduly affect the system under study. Here we report aberrant electrical activity, similar to interictal spikes, and accompanying fluorescence events in some genotypes of transgenic mice expressing GCaMP6 genetically-encoded calcium sensors. These epileptiform events have been observed particularly, but not exclusively, in mice with Emx1-Cre and Ai93 transgenes, across multiple laboratories. The events occur at >0.1 Hz, are very large in amplitude (>1.0 mV local field potentials, >10% df/f widefield imaging signals), and typically cover large regions of cortex. Many properties of neuronal responses and behavior seem normal despite these events, though rare subjects exhibit overt generalized seizures. The underlying mechanisms of this phenomenon remain unclear, but we speculate about possible causes on the basis of diverse observations. We encourage researchers to be aware of these activity patterns while interpreting neuronal recordings from affected mouse lines and when considering which lines to study

Initiation of health-behaviour change among employees participating in a web-based health risk assessment with tailored feedback

<p>Abstract</p> <p>Background</p> <p>Primary prevention programs at the worksite can improve employee health and reduce the burden of cardiovascular disease. Programs that include a web-based health risk assessment (HRA) with tailored feedback hold the advantage of simultaneously increasing awareness of risk and enhancing initiation of health-behaviour change. In this study we evaluated initial health-behaviour change among employees who voluntarily participated in such a HRA program.</p> <p>Methods</p> <p>We conducted a questionnaire survey among 2289 employees who voluntarily participated in a HRA program at seven Dutch worksites between 2007 and 2009. The HRA included a web-based questionnaire, biometric measurements, laboratory evaluation, and tailored feedback. The survey questionnaire assessed initial self-reported health-behaviour change and satisfaction with the web-based HRA, and was e-mailed four weeks after employees completed the HRA.</p> <p>Results</p> <p>Response was received from 638 (28%) employees. Of all, 86% rated the program as positive, 74% recommended it to others, and 58% reported to have initiated overall health-behaviour change. Compared with employees at low CVD risk, those at high risk more often reported to have increased physical activity (OR 3.36, 95% CI 1.52-7.45). Obese employees more frequently reported to have increased physical activity (OR 3.35, 95% CI 1.72-6.54) and improved diet (OR 3.38, 95% CI 1.50-7.60). Being satisfied with the HRA program in general was associated with more frequent self-reported initiation of overall health-behaviour change (OR 2.77, 95% CI 1.73-4.44), increased physical activity (OR 1.89, 95% CI 1.06-3.39), and improved diet (OR 2.89, 95% CI 1.61-5.17).</p> <p>Conclusions</p> <p>More than half of the employees who voluntarily participated in a web-based HRA with tailored feedback, reported to have initiated health-behaviour change. Self-reported initiation of health-behaviour change was more frequent among those at high CVD risk and BMI levels. In general employees reported to be satisfied with the HRA, which was also positively associated with initiation of health-behaviour change. These findings indicate that among voluntary participating employees a web-based HRA with tailored feedback may motivate those in greatest need of health-behaviour change and may be a valuable component of workplace health promotion programs.</p

Association between air pollution and asthma admission among children in Hong Kong

OBJECTIVE: To examine the association of air pollutants with hospital admission for childhood asthma in Hong Kong. METHODS: Data on hospital admissions for asthma, influenza and total hospital admissions in children aged ≤18 years at all Hospital Authority hospitals during 1997–2002 were obtained. Data on daily mean concentrations of particles with aerodynamic diameter <10 μm (i. e. PM(10)) and <2.5 μm (i. e. PM(2.5)), nitrogen dioxide (NO(2)), sulphur dioxide (SO(2)), and ozone (O(3)) and data on meteorological variables were associated with asthma hospital admissions using Poisson's regression with generalized additive models for correction of yearly trend, temperature, humidity, day-of-week effect, holiday, influenza admissions and total hospital admission. The possibility of a lag effect of each pollutant and the interaction of different pollutants were also examined. RESULTS: The association between asthma admission with change of NO(2), PM(10), PM(2.5) and O(3) levels remained significant after adjustment for multi-pollutants effect and confounding variables, with increase in asthma admission rate of 5.64% (3.21–8.14) at lag 3 for NO(2), 3.67% (1.52–5.86) at lag 4 for PM(10), 3.24% (0.93–5.60) at lag 4 for PM(2.5) and 2.63% (0.64–4.67) at lag 2 for O(3). Effect of SO(2) was lost after adjustment. CONCLUSION: Ambient levels of PM(10), PM(2.5), NO(2) and O(3) are associated with childhood asthma hospital admission in Hong Kong