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Search Results: 1 - 10 of 2204 matches for " Augustine Lam "
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Removal of Steriod Hormones by Activated Carbon Adsorption—Kinetic and Thermodynamic Studies  [PDF]
Augustine O. Ifelebuegu
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.36057
Abstract: The mechanism, isotherms and kinetics of removal of two endocrine disrupting chemicals, 17β-estradiol (E2) and 17α-ethinyloestradiol (EE2) by activated carbon adsorption were investigated in an agitated non-flow batch adsorption studies. Mathematical models were used to describe the adsorption phenomenon with the kinetic and thermodynamic parameters evaluated using the adsorption equilibrium data at varying temperatures. Higher adsorption rates were achieved at acidic to neutral pH ranges, with the sorption kinetic data showing a good fit to the pseudo second order rate equation and the Langmuir adsorption isotherm model for both E2 and EE2. The Gibbs free energy were –16.68 kJ/mol and –17.34 kJ/mol for E2 and EE2 respectively. The values of enthalpy for both E2 (84.50 kJ/mol) and EE2 (90 kJ/mol) indicated a chemical nature of the sorption process. Both the isotherm and thermodynamic data obtained all supported the mechanism of adsorption of E2 and EE2 to be mainly chemisorptions supported by some physical attractions.
A Chi-Square Approximation for the F Distribution  [PDF]
L. Jiang, Augustine Wong
Open Journal of Statistics (OJS) , 2018, DOI: 10.4236/ojs.2018.81010
Abstract: F distribution is one of the most frequently used distributions in statistics. For example, it is used for testing: equality of variances of two independent normal distributions, equality of means in the one-way ANOVA setting, overall significance of a normal linear regression model, and so on. In this paper, a simple chi-square approximation for the cumulative distribution of the F-distribution is obtained via an adjusted log-likelihood ratio statistic. This new approximation exhibits remarkable accuracy even when the degrees of freedom of the F distribution are small.
Health services research in the public healthcare system in Hong Kong: An analysis of over 1 million antihypertensive prescriptions between 2004–2007 as an example of the potential and pitfalls of using routinely collected electronic patient data
Martin CS Wong, Johnny Y Jiang, Jin-ling Tang, Augustine Lam, Hong Fung, Stewart W Mercer
BMC Health Services Research , 2008, DOI: 10.1186/1472-6963-8-138
Abstract: Data on antihypertensive drug prescriptions were retrieved from the electronic Clinical Management System (e-CMS) of all primary care clinics run by the Health Authority (HA) in the New Territory East (NTE) cluster of Hong Kong between January 2004 and June 2007. Information was also retrieved on patients' demographic and socioeconomic characteristics, visit type (new or follow-up), and relevant diseases (International Classification of Primary Care, ICPC codes).1,096,282 visit episodes were accessed, representing 93,450 patients. Patients' demographic and socio-economic details were recorded in all cases. Prescription details for anti-hypertensive drugs were missing in only 18 patients (0.02%). However, ICPC-code was missing for 36,409 patients (39%). Significant independent predictors of whether disease codes were applied included patient age ≥ 70 years (OR 2.18), female gender (OR 1.20), district of residence (range of ORs in more rural districts; 0.32–0.41), type of clinic (OR in Family Medicine Specialist Clinics; 1.45) and type of visit (OR follow-up visit; 2.39).In the 57,041 patients with an ICPC-code, uncomplicated hypertension (ICPC K86) was recorded in 45,859 patients (82.1%). The characteristics of these patients were very similar to those of the non-coded group, suggesting that most non-coded patients on antihypertensive drugs are likely to have uncomplicated hypertension.The e-CMS database of the HA in Hong Kong varies in quality in terms of recorded information. Potential future health services research using demographic and prescription information is highly feasible but for disease-specific research dependant on ICPC codes some caution is warranted. In the case of uncomplicated hypertension, future research on pharmaco-epidemiology (such as prescription patterns) and clinical issues (such as side-effects of medications on metabolic parameters) seems feasible given the large size of the data set and the comparability of coded and non-coded patients.T
Alternative Binders for Increased Sustainable Construction in Ghana—A Guide for Building Professionals  [PDF]
Mark Bediako, Augustine Osei Frimpong
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.412A004
Abstract:

Sustainable concepts and practices have taken a centre-stage in different fields of studies and professions. This is because human activities continue to threaten the carrying capacity of earth resources as well as life basic needs such as shelter. Ghana, a developing nation, has been characterized with a boom in construction activities. In almost every constructional work, Portland cement remains the main binding agent that is used to bind aggregates together in a monolithic unit. The overdependence of the Ghanaian construction industry on Portland cement has contributed to huge sums of foreign exchange used to import cement ingredients, high cost of buildings and annual artificial shortages of cement which leads to high cost of the product. In this work, alternative binding agentpozzolana cement, is reported with regards to the theory behind its utilization, laboratory results and practical applications. Results obtained from both the laboratory and the field works have shown that the future binder for the Ghanaian construction industry is pozzolana cement. CSIR-Building and Road Research Institute recommends it for the construction industry for use in various forms of construction such as block making, concrete and mortar works.

Irrigation Suitability Assessment of Effluents From West Kano Rice Irrigation Scheme, Kisumu, Kenya
AO Augustine
Ethiopian Journal of Environmental Studies and Management , 2009,
Abstract: This paper assesses the suitability of West Kano Rice Irrigation Scheme effluents for recycling. Water and wastewater quality variables of ten samples from two sites were determined. The variables were Temperature, Electrolytic conductivity, Total suspended solids, pH, Calcium, Nitrates, Potassium, Sodium and Total Dissolved Solids (TDS). The results were used to compute the Sodium adsorption ratio (SAR), and further compared with FAO irrigation water standards. The wastewater recorded statistically significant gain in Calcium, Nitrates, and TDS, depicting a heavy loss of these vital soil constituents to Lake Victoria. Nitrate levels indicated a deficit in lake water, and an excess in effluents. The excess nitrates in effluents pollute the lake, but could help as crop nutrients when recycled, while low nitrate levels in the lake water would require an addition of fertilizers to the irrigated soils. Annually, a total of 12.26 million m3 of water and 8.94 million m3 of effluents is pumped into and out of the scheme respectively. The effluent and Lake water has SAR of 35% and 18% respectively, rendering both of poor irrigation quality, though the effluents have a compensatory advantage due to its higher levels of Calcium (0.91me/l), compared with the Lake water’s 0.48me/l. The wastewater, with an irrigation suitability rating of 45%, was found more suitable for irrigation than the Lake water’s 40%. It was concluded that the irrigation wastewater was more suitable for use in the scheme than the Lake Victoria waters. It was recommended that the recycling of the irrigation wastewater should be adopted. Key Words: Irrigation; Recycling; Pollution; Waste; Water Quality; Wastewater.
Safe surgical approach to deep pontomedullary cavernoma: An iMRI-assisted resection
Adeolu Augustine
Neurology India , 2005,
Abstract:
Impact of air pollution on the environment in Port Harcourt, Nigeria
Augustine C.
Journal of Environmental Science and Water Resources , 2012,
Abstract: The enforcement of air quality standards for populated urban areas has led to increasing attention to assessment of air quality management areas, where violation of air quality standards occurs, and development of control strategies to eliminate such violation of air quality standards. The Port Harcourt (Lat 4.78oN, Long 7.01oE and Elevation 468m) urban area is very densely built and has heavy motorized traffic. The increase of emissions mainly from traffic and industry are responsible for the increase in atmospheric pollution levels during the last years. The following air pollutants: carbon monoxide, sulphur dioxide, nitrogen dioxide, hydrogen sulphide and ozone, were measured with the WolfSense Multiple Gas Analyzer. The observed levels of CO, a criteria pollutant, exceeded the set limits of 10 and 11.4 μg/m3 by Department of Petroleum Resources (DPR) and Federal Ministry of environment (FMEnvr), respectively while SO2 exceeded the set limits of 0.1 μg/m3 by DPR. The highest levels of CO and SO2 emissions was observed at mile-1 market road.
Humanism and realism in International Humanitarian Law
Augustine Brannigan
The Canadian Journal of Sociology , 2009,
Abstract:
Revisit the Two Sample t-Test with a Known Ratio of Variances  [PDF]
Yongxiu She, Augustine Wong, Xiaofeng Zhou
Open Journal of Statistics (OJS) , 2011, DOI: 10.4236/ojs.2011.13018
Abstract: Inference for the difference of two independent normal means has been widely studied in staitstical literature. In this paper, we consider the case that the variances are unknown but with a known relationship between them. This situation arises frequently in practice, for example, when two instruments report averaged responses of the same object based on a different number of replicates, the ratio of the variances of the response is then known, and is the ratio of the number of replicates going into each response. A likelihood based method is proposed. Simulation results show that the proposed method is very accurate even when the sample sizes are small. Moreover, the proposed method can be extended to the case that the ratio of the variances is unknown.
Inference for the Normal Mean with Known Coefficient of Variation  [PDF]
Yuejiao Fu, Hangjing Wang, Augustine Wong
Open Journal of Statistics (OJS) , 2013, DOI: 10.4236/ojs.2013.36A005
Abstract:

Inference for the mean of a normal distribution with known coefficient of variation is of special theoretical interest be- cause the model belongs to the curved exponential family with a scalar parameter of interest and a two-dimensional minimal sufficient statistic. Therefore, standard inferential methods cannot be directly applied to this problem. It is also of practical interest because this problem arises naturally in many environmental and agriculture studies. In this paper we proposed a modified signed log likelihood ratio method to obtain inference for the normal mean with known coeffi- cient of variation. Simulation studies show the remarkable accuracy of the proposed method even for sample size as small as 2. Moreover, a new point estimator for the mean can be derived from the proposed method. Simulation studies show that new point estimator is more efficient than most of the existing estimators.

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