bluuebunny/crossref_metadata_2025 huggingface dataset:
Using Experimental Designs, Assisted History-Matching Tools, and Bayesian Framework To Get Probabilistic Gas-Storage Pressure Forecasts
Authors: Schaaf Thomas , Coureaud Bertrand , Labat Nicolas , Busby Daniel
Published: September 2009

One of the main concerns in the oil and gas business is generating reliable reservoir hydrodynamics forecasts. Such profiles are the cornerstones of optimal technico-economical management decisions. A workflow combining different methods to integrate and reduce most of the subsurface uncertainties using multiple history matched models (explaining the past) to infer reasonably reliable forecasts is proposed.

A sensitivity study is first performed using experimental design to scan the whole range of static and dynamic uncertainty parameters using a proxy model of the fluid-flow simulator. Only the most sensitive ones with respect to an objective function (OF) (quantifying the mismatch between the simulation results and the observations) are retained for subsequent steps.

Assisted history-matching tools are then used to obtain multiple history-matched models.

To obtain probabilistic pressure profiles, multiple history-matched models are combined with the uncertain parameters not retained in the sensitivity study, using the joint modeling method.

Another way to constrain uncertain parameters with observation data is to use Bayesian framework where a posteriori distributions of the input parameters are derived from the a priori distributions and the likelihood function. The latter is computed through a nonlinear proxy model using experimental design, kriging, and dynamic training techniques.

These two workflows have been applied to a real gas storage case submitted to significant seasonal pressure variations. The obtained probabilistic operational pressure profiles for a given period are then compared to the actual gas storage dynamic behavior so that we can compare the two approaches and assess the added value of both proposed workflows.
Virulence factor activity relationships for hepatitis E and Cryptosporidium
Authors: Fayer Ronald , Orlandi Palmer , Perdue Michael L.
Published: September 2009

The hepatitis E virus and Cryptosporidium are waterborne pathogens, each consisting of distinct taxa, genotypes and isolates that infect humans, nonhuman animal species or both. Some are associated with disease, others are not. Factors contributing to disease are extremely complicated, possibly involving differences in one or more traits associated with an organism's taxon, genotype or isolate and its infectious dose, and age or condition, as well as the host's physiology and immune status. Potential virulence factors have not yet been identified for HEV. Putative virulence factors for Cryptosporidium might be found in recently recognized genes involved in processes such as excystation, adherence to host cells, invasion, intracellular maintenance and host cell destruction.
Prospects for applying virulence factor–activity relationships (VFAR) to emerging waterborne pathogens
Authors: Cangelosi Gerard A.
Published: September 2009

This paper addresses the potential for using virulence factor–activity relationships (VFAR) to discover and detect emerging waterborne pathogens. Emerging pathogens present two challenges to drinking water safety. The first is to improve the predictive value of tests for novel organisms that have recently been identified as emerging waterborne health threats, but are not yet well characterized. There are potential applications for VFAR in meeting this challenge, most notably to distinguish pathogens from closely related nonpathogenic organisms that may also be present in water samples. The second challenge is to prospectively identify new organisms that are not yet known to be health risks to humans, but have the potential of becoming so. This goal is more ambitious. Many microbial virulence factors have multiple functions, some of which are innocuous. Moreover, dedicated virulence factors can be found in pathogens that infect non-human hosts, but pose no threat to humans. These issues complicate the near-term use of VFAR as a first line indicator of pathogenicity. However, our understanding of microbial pathogenesis continues to expand exponentially. As known virulence factors increase in number, so too does the feasibility of a prognostic VFAR strategy.
Does the possession of virulence factor genes mean that those genes will be active?
Authors: Edberg Stephen C.
Published: September 2009

There are a number of relationships the host can establish with the microbes we ingest. For the vast majority of microbes, they have a short-lived liaison with the human host. Either they are destroyed by the stomach acid or bile, or can not establish even a temporary residency in the gastrointestinal tract. Early in life the mucosal surfaces of the body establishes a resident, and generally stable, normal flora. These normal flora microbes, the majority of which are bacteria, have specific receptors for specific areas of the alimentary tract. If the foreign microbe can establish residency, it then may transiently or permanently become part of the normal flora. However, in order to produce disease, it must possess an additional set of virulence factors. While some of these are known, many are not. Those that are known include enzymes, such as protease, lipase, and esterase. Accordingly, VFAR may not be associated with human disease and its presence or absence has no public health meaning.
Where future emerging pathogens will come from and what approaches can be used to find them, besides VFARs
Authors: Sobsey Mark D. , Pillai Suresh D.
Published: September 2009

A consideration of available evidence for some known and well-characterized waterborne pathogens suggests that the diversity of pathogen virulence mechanisms and properties is too great to specifically predict the emergence and future human health impacts of new waterborne pathogens. However, some future emerging pathogens are existing microbes that will be discovered to cause disease. Some will arise from existing ones by either predictable evolutionary and adaptation changes or by unpredictable changes involving a variety of biotic and abiotic mechanisms. Many, and perhaps most, emerging waterborne human pathogens will be zoonotic agents or come from other non-human reservoirs. The emergence of some waterborne pathogens will be related to antibiotic use, resulting in emerging antibiotic-resistant waterborne pathogens. Reliably predicting pathogen emergence and human health effects based on VFARs or other properties of microbes and their hosts is not possible at this time. This is because of (1) the diversity of microbes and their virulence and pathogenicity properties, (2) their ability to change unpredictably, (3) their intimate and diverse interrelationships with a myriad of hosts and dynamic natural and anthropogenic environments and (4) the subtle variations in the immune status of individuals. The best available approach to predicting waterborne pathogen emergence is through vigilant use of microbial, infectious disease and epidemiological surveillance. Understanding the microbial metagenome of the human body can also lead to a better understanding of how we define and characterize pathogens, commensals and opportunists.
Optimal degradation of dye wastewater by ultrasound/Fenton method in the presence of nanoscale iron
Authors: Hsieh Ling-Ling , Kang Hui-Jei , Shyu Huey-Lih , Chang Chen-Yu
Published: September 2009

An advanced ultrasound/Fenton/nanoscale iron oxidation process was applied for treatment of dye wastewater. In this study, the Taguchi statistical method was used to design experiments for the optimization of the ultrasound/Fenton/nanoscale iron process. The experimental design consisted of testing five factors (dosage of H2O2, concentration of Fe2 + , amount of nanoscale iron added, treatment time, and initial pH), with four levels of each factor tested. Chemical oxygen demand (COD) measurements were conducted to determine the efficiency of the water samples. An analysis of the mean sign-to-noise (S/N) ratio indicated that the optimum combination of levels of the factors providing maximal COD reduction of aqueous azo dyes (500 mg/L) were: treatment time = 60 min, dosage of nanoscale iron = 1 g/L, initial pH = 2, and ratio of [dye]:[H2O2]:[Fe2 + ]=1:3.6:2.4. The efficiencies of decolorization and COD reduction were accomplished under these optimum conditions at levels of 99.91% and 63.36%, respectively. The percentage contribution of each factor was determined by the analysis of variance (ANOVA). The results show that the contributions of the five factors—dosage of H2O2, concentration of Fe2 + , amount of nanoscale iron added, treatment time, and initial pH—were 29.33%, 21.37%, 22.51%, 12.93% and 12.35%, respectively.
A literature based study of stormwater harvesting as a new water resource
Authors: Hamdan Sami M.
Published: September 2009

Rainwater harvesting is an important new water resource that participates in bridging the deficit in the water resources in water scarce countries. It is not a new technology but it has been practiced in many countries for many years. From a quantitative point of view it makes a positive contribution to the water resources balance. However, the quality of this new water resource was under the subject of this study in addition to the historical and international experiences carried out in stormwater management. Rainwater harvested from rooftops was noted to be much cleaner than that coming from urban stormwater runoff. The water quality parameters in stormwater were examined with a focus on heavy metals such as Cd, Zn, Pb and Cu which are released in low pH values. Fortunately, heavy metals like other ionic bounds and metal oxide bounds are removed by precipitation or co-precipitation at high values of pH.
Quantification of groundwater recharge in a hard rock terrain of Orissa: a case study
Authors: Sethi Ranu Rani , Kumar A. , Sharma S. P.
Published: September 2009

A study was carried out to select the best method to estimate groundwater recharge in a hard rock terrain. Various standard empirical methods, soil-moisture balance method, water table fluctuation (WTF) method and commonly adopted norms set by Groundwater Estimation Committee (GEC), Govt of India were used to estimate recharge for the Munijhara watershed in the Nayagarh block of Orissa (India). The empirical formulae gave recharge rates ranging from 13 cm to 32 cm/year with average of 22.4 cm and standard deviation of 5.34, independent of other influencing factors like soil, topography and geology. The soil-moisture balance study indicated that recharge is more dependent on the continuous heavy rainfall total annual volume of rainfall. Recharge was limited at up to 10 mm per day, possibly due to presence of hard rock below the soil surface. The rise in water table depth was 3.45 m to 5.35 m with a mean rise of 4.5 m during the year 2006–2007. Annual groundwater recharge based on the WTF approach varied from 10.3 to 16.85 cm with a mean of 13.5 cm, standard deviation of 1.57 cm and coefficient of variation 11.57%. This recharge accounted for 8 to 14% of rainfall received. With a water budget approach based on GEC norms, recharge was calculated as 17 cm per year. The study showed that the magnitudes of annual groundwater recharge as estimated by the WST method and GEC norms are in conformity with other recent findings in India under the same climate conditions. Based on the results recharge structures could be planned in suitable locations to reduce fallow areas under the watershed.
Treatment of As(V) and As(III) by electrocoagulation using Al and Fe electrode
Authors: Kuan W. H. , Hu C. Y. , Chiang M. C.
Published: September 2009

A batch electrocoagulation (EC) process with bipolar electrode and potentiodynamic polarization tests with monopolar systems were investigated as methods to explore the effects of electrode materials and initial solution pH on the As(V) and As(III) removal. The results displayed that the system with Al electrode has higher reaction rate during the initial period from 0 to 25 minutes than that of Fe electrode for alkaline condition. The pH increased with the EC time because the As(V) and As(III) removal by either co-precipitation or adsorption resulted in that the OH positions in Al-hydroxide or Fe-hydroxide were substituted by As(V) and As(III). The pH in Fe electrode system elevate higher than that in Al electrode because the As(V) removal substitutes more OH position in Fe-hydroxide than that in Al-hydroxide. EC system with Fe electrode can successfully remove the As(III) but system with Al electrode cannot because As(III) can strongly bind to the surface of Fe-hydroxide with forming inner-sphere species but weakly adsorb to the Al-hydroxide surface with forming outer-sphere species. The acidic solution can destroy the deposited hydroxide passive film then allow the metallic ions liberate into the solution, therefore, the acidic initial solution can enhance the As(V) and As(III) removal. The over potential calculation and potentiodynamic polarization tests reveal that the Fe electrode systems possess higher over potential and pitting potential than that of Al electrode system due to the fast hydrolysis of and the occurrence of Fe-hydroxide passive film.
Legionella prevalence in wastewater treatment plants of Taiwan
Authors: Huang S. W. , Hsu B. M. , Ma P. H. , Chien K. T.
Published: September 2009

Legionella is a bacterium that is ubiquitous in natural and artificial aquatic environments. Some species of Legionella are recognized as opportunistic potential human pathogens. We investigated the distribution of Legionella at seventeen WWTPs throughout Taiwan. Legionella were detected in 10 of the 17 WWTPs (58.8%) and 25 of 41 samples (61.0%). In the integrated, hospital, industrial and domestic wastewater systems were 13/18 (72.2%), 7/12 (58.3%), 2/7 (28.6%) and 3/4 (75.0%) of the samples were positive for Legionella, respectively. The most frequently encountered species were L. donaldsonii and uncultured L. spp., which were both found in 10 samples (24.4% of all samples), then followed by L. lytica (4.9%) and L. pneumophila (4.9%). L. anisa was detected in one sample (2.4%). The results of this survey confirm that Legionella are ubiquitous in WWTPs in Taiwan. Therefore, long-term investigations should be conducted to evaluate the overall occurrence of Legionella in WWTPs in Taiwan.
Hybrid moving bed biofilm reactors: an effective solution for upgrading a large wastewater treatment plant
Authors: Mannina Giorgio , Viviani Gaspare
Published: September 2009

Over the last few years there has been a growing attention regarding the receiving water body quality state. As a matter of a fact, the Directive 91/271 of the European Union (EU) replaced the “emission standard” concept that fixes discharge limits depending on polluting emission characteristics, with the “stream standard” concept that fixes discharge limits for each polluting substance depending on self-depurative characteristics of the RWB. In this context, several WWTPs need to be upgraded in order to meet stricter effluent limits. The need of WWTP upgrading was also emphasized by the growing urbanization that have led, in most cases, to get overloaded WWTP due to an overcoming of the maximum WWTP capacity. In order to upgrade existing WWTP basically two main possibilities can be chosen: building new tanks or modify the WWTP by introducing new technologies such as the HMBBR systems. In this paper, such latter possibility was explored and as a case study an existing Italian WWTP (Acqua dei Corsari) located in Palermo (IT) was analysed. The main goal was to test the effectiveness of HMBBR systems with respect to the WWTP upgrading. The survey was carried out by means of model simulation and an HMBBR pilot plant. This latter was employed for the evaluation of the model parameters as well as kinetic coefficients for the HMBBR. The model results are encouraging towards the WWTP upgrading by means of HMBBR. As a matter of fact, the model simulation results showed that the WWTP maximum capacity can be upgraded from 480,000 up to one million PE.
Kinetic analysis of attached growth nitrification in cold climates
Authors: Delatolla R. , Tufenkji N. , Comeau Y. , Gadbois A. , Lamarre D. , Berk D.
Published: September 2009

The rate of nitrification within a laboratory-scale Biological Aerated Filtration treatment system at 4°C was investigated during an exposure time of approximately four months (acclimatized experiments). In addition, shock experiments from 20°C to 4°C and from 4°C to 20°C were performed. The acclimatized experiments demonstrated that the exposure time the system remained at low temperature strongly affects the rates of nitrification. Nevertheless, the experiments showed that significant nitrification rates are maintained for up to 115 days at 4°C. The rate of ammonia removal after an exposure time of 115 days at 4°C was shown to be as high as 16% of the rate of removal observed at 20°C. The 20°C to 4°C shock experiment demonstrated a 56% decrease in the rate of ammonia removal. On the other hand, the 4°C to 20°C shock experiment demonstrated an increase in the relative rates of ammonia removal of up to 300% when compared to rates of removal measured after 115 days at 4°C. Thus, although the rates of nitrification have been shown to decrease significantly as a function of exposure time at 4°C, the process has demonstrated important rates of ammonia removal at 4°C for the approximate span of the North American winter.
Geochemical changes during recharge with tertiary-treated wastewater at a coastal sandfill
Authors: Chua Lloyd H. C. , Lo Edmond Y. M. , Lim Teik Thye , Robertson Alexander P. , Shuy Eng Ban , Tan Soon Keat
Published: September 2009

Results of experiments investigating geochemical changes during artificial recharge of treated wastewater at a coastal sandfill, reclaimed with sand dredged from the seabed, are reported in this paper. Laboratory batch experiments were conducted using secondary effluent (SE) and SE treated with an additional ultrafiltration process (UF), and wastewater treated by reverse osmosis (RO) process, mixed with surface sand obtained from the sandfill. Experiments with RO showed a net increase of 0.41 meq/L, 0.12 meq/L and 0.31 meq/L for Ca2 + , Mg2 +  and HCO3−, respectively. UF and SE also exhibited net increase in Ca2 + , Mg2 +  and HCO3− indicating carbonate mineral dissolution. All three waters were found to be over-saturated with respect to calcite. Carbonate dissolution reactions were observed in the field experiments. However, the presence of imported clays from the borrow source gave rise to ion exchange reactions where Na+ attached to the clay particles were exchanged for Ca2 +  and Mg2 +  inducing mineral dissolution, driven by sub-saturation conditions. This resulted in an increase in pH with maximum values in excess of 9.0. It was also found that the sodium adsorption ratio remained high (>10) even after the groundwater had been diluted sufficiently to freshwater levels (ionic strength, I<0.015) indicating a potential for the dispersion of clay particles. This could have a deleterious consequence on porosity and hydraulic conductivity.
Sustainable Urban Drainage Systems (SUDS) treatment train assessment tool
Authors: Jefferies C. , Duffy A. , Berwick N. , McLean N. , Hemingway A.
Published: September 2009

This paper outlines a rationale and scoring system for the stormwater treatment train assessment tool (STTAT) which is a proposed regulatory tool for Sustainable Urban Drainage Systems (SUDS). STTAT provides guidance and regulatory consistency for developers about the requirements of planners and the Scottish Environment Protection Agency (SEPA). The tool balances the risks of pollution to the receiving water body with the treatment provided in a treatment train. It encourages developers to take SUDS into account early, avoiding any misunderstanding of SUDS requirements at the planning stage of a development. A pessimistic view on pollution risks has been adopted since there may be a change of land use on the development in the future. A realistic view has also been taken of maintenance issues and the ‘survivability’ of a SUDS component. The development of STTAT as a response to the requirements of the Water Framework Directive is explored, the individual scores being given in tabular format for receiving water and catchment risks. Treatment scores are proposed for single SUDS components as well as multiple components within treatment trains. STTAT has been tested on a range of sites, predominantly in Scotland where both development and receiving water information was known. The operational tool in use by SEPA is presented.
Fibre-optic distributed temperature sensing in combined sewer systems
Authors: Schilperoort R. P. S. , Clemens F. H. L. R.
Published: September 2009

This paper introduces the application of fibre-optic distributed temperature sensing (DTS) in combined sewer systems. The DTS-technique uses a fibre-optic cable that is inserted into a combined sewer system in combination with a laser instrument that performs measurements and logs the data. The DTS-technique allows monitoring in-sewer temperatures with dense spatial and temporal resolutions. The installation of a fibre-optic cable in a combined sewer system has proven feasible. The use of a single instrument in an easy accessible and safe location that can simultaneously monitor up to several hundreds of monitoring locations makes the DTS set-up easy in use and nearly free of maintenance. Temperature data from a one-week monitoring campaign in an 1,850 m combined sewer system shows the level of detail with which in-sewer processes that affect wastewater temperatures can be studied. Individual discharges from house-connections can be tracked in time and space. With a dedicated cable configuration the confluence of wastewater flows can be observed with a potential to derive the relative contributions of contributary flows to a total flow. Also, the inflow and in-sewer propagation of stormwater can be monitored.
Biological treatment of winery wastewater: an overview
Authors: Andreottola G. , Foladori P. , Ziglio G.
Published: September 2009

The treatment of winery wastewater can realised using several biological processes based both on aerobic or anaerobic systems using suspended biomass or biofilms. Several systems are currently offered by technology providers and current research envisages the availability of new promising technologies for winery wastewater treatment. The present paper intends to present a brief state of the art of the existing status and advances in biological treatment of winery wastewater in the last decade, considering both lab, pilot and full-scale studies. Advantages, drawbacks, applied organic loads, removal efficiency and emerging aspects of the main biological treatments were considered and compared. Nevertheless in most treatments the COD removal efficiency was around 90–95% (remaining COD is due to the un-biodegradable soluble fraction), the applied organic loads are very different depending on the applied technology, varying for an order of magnitude. Applied organic loads are higher in biofilm systems than in suspended biomass while anaerobic biofilm processes have the smaller footprint but in general a higher level of complexity.
Effects of timing of water stress on yield and berry size
Authors: Greven M. M. , Raw V. , West B. A.
Published: September 2009

Past irrigation research in Marlborough showed that reducing irrigation on grapes by up to 60% would not have any impact on yield, but that the timing of the irrigation might be important for maintenance of yields. A research trial was set up with Sauvignon blanc grapes planted in containers; periods of water stress were applied for three weeks at different times of the growing season. During the three years of the trial the post-flowering (PO-F) period was consistently most sensitive to water stress. At harvest time, the crop yields for the PO-F water-stressed vines were 55%, 72% and 90% of control yields for the three consecutive years, and the bunch weights were 59%, 84% and 95%. Berry weights for the PO-F water-stressed vines were 87%, 96% and 73% of the control values, although the second-year difference was not significant. In two years out of three, there was a trend for PO-F and pre-veraison (PR-V) water-stressed vines to have the lowest berry soluble solids contents (°Brix), indicating a delay in maturity. We suggest that to use irrigation sustainably, it is safe to reduce water applications for most of the season, but that immediately after flowering, any water stress should be avoided. During the period leading up to veraison, some mild water stress can be applied.
Carbon footprint of aerobic biological treatment of winery wastewater
Authors: Rosso D. , Bolzonella D.
Published: September 2009

The carbon associated with wastewater and its treatment accounts for approximately 6% of the global carbon balance. Within the wastewater treatment industry, winery wastewater has a minor contribution, although it can have a major impact on wine-producing regions. Typically, winery wastewater is treated by biological processes, such as the activated sludge process. Biomass produced during treatment is usually disposed of directly, i.e. without digestion or other anaerobic processes. We applied our previously published model for carbon-footprint calculation to the areas worldwide producing yearly more than 106 m3 of wine (i.e., France, Italy, Spain, California, Argentina, Australia, China, and South Africa). Datasets on wine production from the Food and Agriculture Organisation were processed and wastewater flow rates calculated with assumptions based on our previous experience. Results show that the wine production, hence the calculated wastewater flow, is reported as fairly constant in the period 2005–2007. Nevertheless, treatment process efficiency and energy-conservation may play a significant role on the overall carbon-footprint. We performed a sensitivity analysis on the efficiency of the aeration process (αSOTE per unit depth, or αSOTE/Z) in the biological treatment operations and showed significant margin for improvement. Our results show that the carbon-footprint reduction via aeration efficiency improvement is in the range of 8.1 to 12.3%.
Aerobic treatment of winery wastewater with the aim of water reuse
Authors: Oliveira M. , Queda C. , Duarte E.
Published: September 2009

An air micro-bubble bioreactor (AMBB) using a free self-adapted microbial population, 15 dm3 working volume, was used for aerobic treatment of winery wastewater. This reactor utilizes a Venturi injector in conjunction with mass transfer multiplier nozzles, which allow an efficient oxygen transfer. The reactor can operate in batch or continuous conditions. The dynamics of chemical oxygen demand (COD), biomass and total contents of polyphenolic compounds was followed throughout each trial. The wastewater COD ranged between 4.0–8.0 kg COD m−3 and the efficiency of the batch treatment was about 90.0±4.3%, after 6 days of operation. The maximum efficiency obtained was achieved after 15 days of treatment (99%). In continuous conditions, the loading rate and the treatment efficiency ranged between 0.45–1.00 kg COD m−3 d−1 and 93.3±2.0%, respectively. The AMBB hydraulic retention time was 15 days. To assess the suitability of treated water in relation to vineyard irrigation, the effluent was physico-chemical analysed and direct toxicity bioassays with effluent matrix were carried out using Lepidium sativum L. seeds. The results showed the water quality required to be reutilised minimizing water consumption. This study will contribute for the implementation of an efficient water use plan, aiming the preservation of the water resource and the reduction of the wastewater production.
Membrane bioreactors for winery wastewater treatment: case-studies at full scale
Authors: Guglielmi G. , Andreottola G. , Foladori P. , Ziglio G.
Published: September 2009

The membrane bioreactor technology (MBR) is nowadays a suitable alternative for winery wastewater treatment, thanks to low footprint, complete suspended solids removal, high efficiency in COD abatement and quick start-up. In this paper, data from two full-scale MBRs equipped with flat-sheet membranes (plant A and plant B) are presented and discussed. COD characterisation by respirometry pointed out the high biodegradability degree of both wastewater, with a strong prevalence of the readily biodegradable fraction. An extended version of Activated Sludge Model No. 3 was used to fit the experimental OUR profiles and to assess the maximum growth rate of heterotrophic biomass on sludge samples collected at both sites; the stoichiometric yield coefficients were also calculated. Sludge filterability and dewaterability were investigated with batch tests; laboratory results confirmed the field observations. Finally, some considerations are listed, aimed at defining possible key-issues for optimal process design and operation.
Experimental and theoretical investigations of optical properties of GaN/AlGaN MQW nanostructures. Impact of built-in polarization fields
Authors: Esmaeili M. , Gholami M. , Haratizadeh H. , Monemar B. , Holtz P. , Kamiyama S. , Amano H. , Akasaki I.
Published: September 2009

We report the results from detailed optical spectroscopy from MOCVD grown GaN/AlGaN multiple quantum wells (MQWs), as opposed to most previous studies where MBE was employed by means of photoluminescence (PL) technique. In this paper we will present theoretical and experimental results demonstrating how polarization induced electric fields and bound interface charges in GaN/AlGaN MQWs affect the emission peak energy, PL line shape, as well as the emission line width. Theoretically estimated fields in this work are consistent with experimental data. Transition energy of the heavy hole and electron ground state Ee-hh in GaN/AlGaN MQWs were calculated and it is found that it stays in good agreement with the experimental data.
Repositioning Politics in Education’s Circle of Knowledge
Authors: McDonnell Lorraine M.
Published: September 2009

The model implicit in most research on the politics of education assumes that political factors such as interest group support and opposition shape policy. However, because this perspective yields incomplete information about the educational enterprise, researchers should not just ask what kinds of policies politics creates but also reverse the causal arrow to examine what kinds of politics result from different policies. In addressing this question, the concept of policy feedback focuses analytical attention on the institutional structures and rules policies establish, the elite and public interpretations of those policies, the interests that are mobilized, and how these factors interact to shape future policies.
Comments on Howe: Getting Over the Methodology Wars
Authors: Bredo Eric
Published: September 2009

Howe’s ( 2009 ) critique of positivistic tendencies in the education research community is valuable and pertinent. His analysis is nonetheless one-sided, finding fault with one side of current divisions alone. In an effort to retain the good points of his analysis, the author first summarizes Howe’s argument, interpreting it as a critique of hasty and dogmatic reductionism. He then considers parallel problems arising from hasty and dogmatic holism that Howe does not address. Following this discussion, a third, temporal approach is suggested in which analytic and synthetic perspectives are used to suggest and modify one another in a cycle, rather than being taken as fixed stances. Adopting this approach could help reduce the dogmatism evident in the methodology wars, although struggles for advantage would clearly remain.
Making Aboriginal People ‘Immigrants Too’: A Comparison of Citizenship Programs for Newcomers and Indigenous Peoples in Postwar Canada, 1940s–1960s
Authors: Bohaker Heidi , Iacovetta Franca
Published: September 2009

Abstract:

Canadian citizenship is a young official category of belonging, and the relationship of Aboriginal people to that category remains contested ground: scholars debate the legal status of First Nations people within the Canadian state while other academics and First Nations leaders note that these nations never ceded their sovereignty to a foreign colonial state. While such debates have deep historic roots, more recent post-1945 government policies and programs reveal the extent to which Aboriginal peoples continued to be seen as outsiders who need to be assimilated to the ‘mainstream.’ As a historical contribution to these ongoing debates, this paper explores efforts to create a distinct and common Canadian citizenship in the years after the Second World War when, as a follow-up to the passage of the 1947 Canadian Citizenship Act, the federal government strategically chose to combine its management of immigrant admissions, reception, and citizenship with its Indian Affairs policies under the rubric of one new federal ministry, the Department of Citizenship and Immigration (DCI). From 1950 until 1966, the Indian Affairs branch was located in the DCI, where its activities were heavily modelled after the citizenship campaigns being developed for immigrants within the DCI's Canadian Citizenship Branch. This paper reveals the ways in which ministry officials and their network of public and private groups and agencies aimed to create a one-size-fits-all category of societal Canadian citizenship. To do so they deliberately constructed Aboriginal peoples as ‘immigrants too’ and targeted both ‘Canada's original inhabitants’ and newly arrived European refugees and immigrants with similar ‘Canadianization’ programs. The analysis of the programs targeting both groups highlights the similarities (for example, both Natives and newcomers were constructed as outsiders who needed to adopt dominant middle-class Canadian social and moral codes and pro-capitalist values) and the differences (for example, the immigrant campaigns were more tolerant of cultural differences than the Aboriginal campaigns that, despite their seemingly progressive rhetoric, effectively continued earlier assimilationist policies) as well as their gendered and class features. In offering this comparative analysis between these twinned postwar campaigns, the paper brings together two histories, Aboriginal and immigrant, that have usually been studied in isolation from each other.
Évaluation des habiletés de communication orale chez des élèves de l'élémentaire utilisant AIM
Authors: Bourdages Johanne S. , Vignola Marie-Josée
Published: September 2009

This article explores the efficiency of AIM (the accelerative integrated method), used in core French classes, by comparing the oral communication skills of Grade 3 French as a second language (FSL) students in a class using AIM to those of Grade 3 FSL students in a regular core French program. AIM has been gaining momentum across Canada since 2000; its objective is to bring FSL learners to a higher level of proficiency relative to other programs using communicative methods (Maxwell, 2001). AIM allows students to use French in context and differs from other teaching practices in its use of gestures corresponding to each word taught. In this study, data were collected during individual interviews. Our results show few significant differences between the AIM group and the non-AIM group.
Congenital Hypothyroidism in the Southern Bangladesh
Authors: Rasul C Habibur , Lucky S Nahar , Miah S Rahman , Moslem F
Published: September 2009

Congenital hypothyroidism is the commonest preventable cause of mental retardation. It is more prevalent in endemic goiter regions like Bangladesh. But magnitude of the problem has not been studied at national level. This study was done to detect the frequency of congenital hypothyroidism in southem part of Bangladesh & to develop neonatal screening program. All the living newborns delivered between Oct 01 to June 05 Khulna Medical College Hospital were included in the study, After taking the relevant information from mother, cord blood sample were collected from the newborn within 120 hours of birth and kept in freezer. At the end of collection of each two months, the lot was sent to the laboratory of Institute of Nuclear Medicine, Dhaka for radioimmunoassay of TSH. Potential cases with TSH above 10 MIU were recalled for thyroid function test for confirmation of diagnosis. Fifteen hundred samples were collected in total during 45 months of study. One forty seven unsatisfactory samples were discarded; thereby 1353 samples were eventually assayed for TSH. Among the study population 88.2% hailed from Khulna district and the rest of the cases came from neighboring districts. Male to female baby ratio was 1.2:1. Regarding the birth weight 33.4% babies were low birth weight. TSH above 10 was found in 35 babies among whom one baby was hypothyroid and the other member of the twin was also hypothyroid although the TSH level was below 10. None of newborn had TSH level above 20. Thus frequency of congenital hypothyroidism was 1.5 per thousand living newborn. Congenital hypothyroidism in southern part of the country is quite high in relation to global incidence. Although this is not the national picture but the high figure is alarming. Therefore neonatal screening program should be implemented as soon as possible to reduce the number of mentally retarded child.   doi: 10.3329/taj.v21i1.3212 TAJ 2008; 21(1): 18-22
Preliminary Report on a Comparative Study on Patients Satisfaction in Private and Public Hospital in the Perspective of Prevailing Health Management Constraints in Rajshahi
Authors: Ekram ARM Saifuddin , Rahman M Fazlur , Salim S Abdullah , Haque M Jawadul
Published: September 2009

Assessment of patient satisfaction is required to help to improve health system performance and promote better governance of the hospital services. Despite resource constraints health personnel in private health care delivery centers are providing satisfactory health services than public hospitals. In the face of ever increasing demand for health care services strength, weakness and future prospects of private health care facilities should be evaluated and appraised. On the other hand health care delivery in public hospitals should be closely monitored for further improvement to meet the demands of people.   doi: 10.3329/taj.v21i1.3213 TAJ 2008; 21(1): 23-30
Accuracy of Mothers Reports Regarding Vaccination Status of Their Children in Urban Bangladesh
Authors: Selimuzzaman ABM , Ullah MA , Haque MJ
Published: September 2009

With the primary view to test the accuracy of the mothers reports regarding their children's immunization status, this study was carried out in the metropolitan areas of Rajshahi among the mothers of 12-23 months old children, Total 1500 mothers were included in this study as sample units by two stage cluster sampling method. In this study, child immunization card retention rate was 66.22%, Majority of the mothers reported accurately about their children's DPT (76%) and measles (85%) vaccination status. It suggests that urban mothers statements about their children' vaccination status is reliable. And in case of DPT young and educated mothers with higher family economic status and having fewer children were comparatively more reliable than others. Field workers should motivate and encourage the mothers to preserve their children's immunization cards.   doi: 10.3329/taj.v21i1.3217 TAJ 2008; 21(1): 40-43
Vasopressor is the Drug of Choice in the Management of Cardiac Arrest Occurring in Early Spinal Anesthesia
Authors: Alam M Intakhab , Rahman M Lutfar , Haque M Ekramul , Jesmin S
Published: September 2009

In Rajshahi Medical College Hospital this experience was based on 8 patients who got high spinal block for intended surgery for Caesarian section. These patients were totally apnoeic, cyanosed and there was no recordable pulse or blood pressure. Cardiac massage and artificial ventilation with rapidly introduced E.T.T. were instituted and inotrope Ephedrine was given without recovery. But when adrenaline was given in diluted form, soon pulse, B.P. respiration and consciousness were regained.   doi: 10.3329/taj.v21i1.3219 TAJ 2008; 21(1): 50-52
Pattern and Clinical Profile of Congenital Heart Disease in A Teaching Hospital
Authors: Sharmin L Shamima , Haque M Azizul , Bari M Iqbal , Ali M Ayub
Published: September 2009

Objectives: To see the (a) type of congenital heart disease, (b) Clinical presentation of the cases, (c) association with extra-cardiac anomalies and disease, (d) complications of different CHD, (e) outcome of patients during hospital stay. Methodology: it was a prospective study conducted in the department of pediatrics of Rajshahi Medical College & Hospital over a period of one year.115 children from birth to 12 years of age who had congenital heart disease confirmed by echocardiography were included. All patients were treated conservatively and observed for immediate out come during the hospital stay. Result: major types of CHD were VSD (42.6%), TOF (18.3%), ASD (14.8%), PDA (7.8%). Male outnumbers female child. Common symptoms were breathlessness (60%), fatigue (54.8%), cough (43.5%), poor weight gain (41.7%), recurrent chest infection (34.8%), fever (28.7%), feeding problems (26.1%), palpitation (21.7%) and bluish discoloration of lips and fingertips (20%). Murmur with or without thrill and cardiomegaly was the most important cardiac finding. Frequently observed complications were heart failure, pulmonary hypertension and growth failure.   doi: 10.3329/taj.v21i1.3221 TAJ 2008; 21(1): 58-62
Target Organ Damage in Hypertension in an Academic Hospital
Authors: Masum QAA , Ahmed M Uddin , Uddin M Refaz , Siddiqui NA , Ekram ARM Saifuddin
Published: September 2009

One hundred hypertensive patients were selected randomly from medicine indoor; 66 were males, 34 were females. Age ranges were 20 to 70+ years. Detail history was taken, comprehensive physical examination and relevant investigations were done to detect various target organ damage. These findings were correlated with age, sex, occupation, socioeconomic status, duration of hypertension, drug compliance and other risk factors of cardiovascular disease. Incidence of TOD were as follows: 65.15% of males and 52.94% of females developed stroke; 70% of total patients developed some forms of cardiac complications, 14% had left ventricular failure, 43.93% of males had left ventricular hypertrophy (LVH) 26.47% of females had LVH; 27% of patients had renal complications; 23% of patients had retinopathies; 6% of patients had malignant hypertension; 20% of patients had peripheral vascular disease.   doi: 10.3329/taj.v21i1.3222 TAJ 2008; 21(1): 63-68
Precocious Puberty- A Case Report
Authors: Shah K Kabiruzzaman , Laz N Begum , Siddique AB , Ahmed FU
Published: September 2009

Appearance of secondary sexual development before the age of 9 in a male child and before the age of 7 in a female child is called precocious puberty. When the cause of precocious puberty is premature activation of the hypothalamic-pituitary axis, it is called central or complete precocious puberty, if ectopic gonadotrophin secretion occurs in boys or autonomous sex steroid secretion occurs in either sex it is called incomplete precocious puberty. |Here we are reporting a 5 year old girl with central precocious puberty.   doi: 10.3329/taj.v21i1.3227 TAJ 2008; 21(1): 83-86
Current Challenges in Hepatitis C
Authors: Ahad M Abdul
Published: September 2009

Hepatitis C is a significant global problem with a wide-ranging personal, social and economic impact. The virus can silently attack the liver for decades before the illness becomes obvious, often as cirrhosis, liver cancer or liver failure. Hepatitis C virus (HCV) is emerging as one of the major health problems in Bangladesh.   doi: 10.3329/taj.v21i1.3229 TAJ 2008; 21(1):93-96
INDEPENDENT COMPONENT APPROACH TO THE ANALYSIS OF HAND GESTURE sEMG AND FACIAL sEMG
Authors: Naik Ganesh R. , Kumar Dinesh K. , Arjunan Sridhar P. , Palaniswami Marimuthu
Published: September 2009

Independent component analysis algorithm, a recently developed multivariate statistical data analysis technique, has been successfully used for signal extraction in the field of biomedical and statistical signal processing. This paper reviews the concept of ICA and demonstrates its usefulness and limitations in the context of surface electromyogram related to hand movements and facial muscles. In the first experiment, ICA has been used to separate the electrical activity from different hand gestures. The second part of our study considers separating electrical activity from facial muscles. In both instances, surface electromyogram has been used as an indicator of muscle activity. The theoretical analysis and experimental results demonstrate that ICA is suitable for the identification of different hand gestures using sEMG signals. The results identify the unsuitability of ICA when the similar techniques are used for the facial muscles in order to perform different vowel classification. This technique could be used as a prerequisite tool to measure the reliability of sEMG based systems in rehabilitations and human computer interaction applications.
NEURONS CULTURED ON GaN AND IS ASSOCIATED WITH SYNAPSIN I AND MAP2 EXPRESSION
Authors: Chen Chi-Ruei , Young Tai-Horng
Published: September 2009

In this work, the behaviors of cerebellar granule neurons prepared from 7-day-old Wistar rats on GaN, GaAs, and silicon were investigated. We believe that this is the first time that the GaN has been used as a substrate for neuron cultures to examine its effect on cell response in vitro. The GaN surface structure and its relationship with cells were examined by scanning electron microscopy (SEM), immunofluorescence lactate dehydrogenase (LDH). Compared with silicon used for most neural chips, neurons seeded on GaN were able to form an extensive neuritic network and expressed very high levels of synapsin I coincident with the neurite outgrowth. LDH assay indicated that GaN improve neuron survival better than silicon and GaAs. Between in seven-day and day 15-cultured neurons, these results are consistent with the influence of GaN, in the regulation of neuronal adhesion, neuritic plasticity and survival, within in vitro. The favorable biocompatibility characteristics of GaN can be used to measure electric signals from networks of neuronal cells in culture to make it a possible candidate for use in a microelectrode array.
QRS COMPLEX DETECTION USING DOUBLE DENSITY DISCRETE WAVELET TRANSFORM
Authors: Kumari Shantha Selva , Sadasivam V.
Published: September 2009

In this paper, an offline double density discrete wavelet transform based QRS complex detection of the electrocardiogram signal is discussed. Baseline wandering present in the signal is removed by using the double density discrete wavelet transformed approximation coefficients of the signal. The results are more accurate than other methods with less effort. This is an unsupervised method allowing the process to be used in offline automatic analysis of electrocardiogram. The measurement of timing intervals of ECG signal by automated system is highly superior to its subjective analysis. The heart rate signals are essentially non-stationary and contain indicators of current disease or warnings about impending diseases. The indicators may be present at all times or may occur at random in the time scale. Double density discrete wavelet transform is easier to implement, provides multiresolution and also reduces the computational time. In the pre-processing step, the baseline wandering is removed from the ECG signal. Then the R peaks/QRS complexes are detected. From the location of the R peaks, the successive RR intervals and heart rate are calculated. Fifty-two records from the MIT-BIH arrhythmia database are used to evaluate the proposed method. Sensitivity and positive prediction are used as performance measures. This method detects the R peaks with 100% sensitivity and 99.95% positive prediction. The performance of the proposed method is better than other methods existing in the literature.