bluuebunny/crossref_metadata_2025 huggingface dataset:
What was the Mental Disease that Afflicted King Saul?
Authors: (Louba) Ben-Noun Liubov
Published: September 2003

In this article, the author discusses the case of the biblical King Saul, the first King of Israel, who ruled the country 3,000 years ago. Evaluation of the passages referring to King Saul's disturbed behavior indicates that he was afflicted by a mental disorder. Among many disorders that could have affected the King, manic episode with psychotic phases, major depression with psychotic features, mixed episode, bipolar disorder I, dysthymic disorder later developed into bipolar disorder, or nonspecific psychotic disorder are the most likely. And among these diagnoses, bipolar disorder I is the most acceptable. The author suggests in this article that the roots of contemporary psychiatry can be traced back to biblical times.
Excessive Gambling and Cognitive Therapy
Authors: Boutin Claude , Dumont Michel , Ladouceur Robert , Montecalvo Patrizia
Published: September 2003

In this article, the authors provide clinical recommendations for addressing issues frequently encountered with gamblers during the course of cognitive treatment. The main clinical topics covered are ambivalence toward abstinence, denial of the gambling problem, lying, and relapse prevention strategies. The authors begin the article with a brief review of the gambling literature, after which they present the case of a 53-year-old gambler to illustrate clinical interventions. Clinical recommendations also are offered.
Hypnotic Dependent Insomnia in an Older Adult with Addiction-Prone Personality
Authors: Cooper Theodore V. , Lichstein Kenneth L. , Aguillard R. Neal
Published: September 2003

Despite the proliferation of safe, effective, and cost-effective behavioral treatments of insomnia, hypnotic medication remains the most common treatment of insomnia by primary care providers. Such treatment in many cases leads to a pattern of tolerance and dependence on sleep medication, as well as difficulty discontinuing treatment and subsequent rebound insomnia. Recent research suggests promise for behavioral interventions in the treatment of hypnotic dependent insomnia. In this article, the authors report on the treatment of a particularly challenging case: an older adult with a history of addictive behavior now dependent on hypnotics. The authors demonstrate the best possible outcome: elimination of sleep medication combined with sleep improvement.
Design and Performance Frameworks for Constructing Problem-Solving Simulations
Authors: Stevens Ron , Palacio-Cayetano Joycelin
Published: September 2003

Rapid advancements in hardware, software, and connectivity are helping to shorten the times needed to develop computer simulations for science education. These advancements, however, have not been accompanied by corresponding theories of how best to design and use these technologies for teaching, learning, and testing. Such design frameworks ideally would be guided less by the strengths/limitations of the presentation media and more by cognitive analyses detailing the goals of the tasks, the needs and abilities of students, and the resulting decision outcomes needed by different audiences. This article describes a problem-solving environment and associated theoretical framework for investigating how students select and use strategies as they solve complex science problems. A framework is first described for designing on-line problem spaces that highlights issues of content, scale, cognitive complexity, and constraints. While this framework was originally designed for medical education, it has proven robust and has been successfully applied to learning environments from elementary school through medical school. Next, a similar framework is detailed for collecting student performance and progress data that can provide evidence of students' strategic thinking and that could potentially be used to accelerate student progress. Finally, experimental validation data are presented that link strategy selection and use with other metrics of scientific reasoning and student achievement.
Bioliteracy and Teaching Efficacy: What Biologists Can Learn from Physicists
Authors: Klymkowsky Michael W. , Garvin-Doxas Kathy , Zeilik Michael
Published: September 2003

The introduction of the Force Concept Inventory (FCI) by David Hestenes and colleagues in 1992 produced a remarkable impact within the community of physics teachers. An instrument to measure student comprehension of the Newtonian concept of force, the FCI demonstrates that active learning leads to far superior student conceptual learning than didactic lectures. Compared to a working knowledge of physics, biological literacy and illiteracy have an even more direct, dramatic, and personal impact. They shape public research and reproductive health policies, the acceptance or rejection of technological advances, such as vaccinations, genetically modified foods and gene therapies, and, on the personal front, the reasoned evaluation of product claims and lifestyle choices. While many students take biology courses at both the secondary and the college levels, there is little in the way of reliable and valid assessment of the effectiveness of biological education. This lack has important consequences in terms of general bioliteracy and, in turn, for our society. Here we describe the beginning of a community effort to define what a bioliterate person needs to know and to develop, validate, and disseminate a tiered series of instruments collectively known as the Biology Concept Inventory (BCI), which accurately measures student comprehension of concepts in introductory, genetic, molecular, cell, and developmental biology. The BCI should serve as a lever for moving our current educational system in a direction that delivers a deeper conceptual understanding of the fundamental ideas upon which biology and biomedical sciences are based.
Evaluation of an Estrogen Receptor-β Agonist in Animal Models of Human Disease
Authors: Harris Heather A. , Albert Leo M. , Leathurby Yelena , Malamas Michael S. , Mewshaw Richard E. , Miller Chris P. , Kharode Yogendra P. , Marzolf James , Komm Barry S. , Winneker Richard C. , Frail Donald E. , Henderson Ruth A. , Zhu Yuan , Keith James C.
Published: September 2003

The discovery of a second estrogen receptor (ER), called ERβ, in 1996 sparked intense interest within the scientific community to discover its role in mediating estrogen action. However, despite more than 6 yr of research into the function of this receptor, its physiological role in mediating estrogen action remains unclear and controversial. We have developed a series of highly selective agonists for ERβ and have characterized their activity in several clinically relevant rodent models of human disease. The activity of one such compound, ERB-041, is reported here. We conclude from these studies that ERβ does not mediate the bone-sparing activity of estrogen on the rat skeleton and that it does not affect ovulation or ovariectomy-induced weight gain. In addition, these compounds are nonuterotrophic and nonmammotrophic. However, ERB-041 has a dramatic beneficial effect in the HLA-B27 transgenic rat model of inflammatory bowel disease and the Lewis rat adjuvant-induced arthritis model. Daily oral doses as low as 1 mg/kg reverse the chronic diarrhea of HLA-B27 transgenic rats and dramatically improve histological disease scores in the colon. The same dosing regimen in the therapeutic adjuvant-induced arthritis model reduces joint scores from 12 (maximal inflammation) to 1 over a period of 10 d. Synovitis and Mankin (articular cartilage) histological scores are also significantly lowered (50–75%). These data suggest that one function of ERβ may be to modulate the immune response, and that ERβ-selective ligands may be therapeutically useful agents to treat chronic intestinal and joint inflammation.
Risking Basin Analysis Results
Authors: Lerche I. , Rocha-Legoretta F.
Published: September 2003

The work presented here uses a basin analysis code, developed for Excel, to handle burial history, fluid flow, fracturing, overpressure development with time, erosion events, kerogen breakdown to oil and gas, hydrocarbon volumetrics for both oil and gas including source retention, migration loss, and area changes with time of source rocks for each formation. The code is remarkably fast, requiring about 0.2 seconds on a laptop to perform all the above calculations for ten formations as well as producing pictorial representations of all variables with space and time. The code seamlessly interfaces with the Monte Carlo risking program Crystal Ball so that a total uncertainty analysis can be done with as many uncertain inputs as required and as many outputs of interest as needed without increasing the computer time needed. A thousand Crystal Ball runs take only about 200 seconds, allowing one to investigate many possible scenarios extremely quickly.

We show here with four basic examples how one goes about identifying which parameters in the input (ranging from uncertain data, uncertain thermal history, uncertain permeability, uncertain fracture coefficients for rocks, uncertain geochemistry kinetics, uncertain kerogen amounts and types per formation, through to uncertain volumetric factors) are causing the greatest contributions to uncertainty in any and all outputs. The relative importance, relative contributions and relative sensitivity are examined to show when it is necessary to know more about the underlying distributions of uncertain parameters, when it is necessary to know more about the dynamic range of a parameter to narrow its contribution to the total uncertainty, and which parameters are necessary to first focus on to narrow their uncertainty in order to improve the dynamical, thermal or hydrocarbon outputs.

An interface of such a coupled pair of very fast Excel codes with an Excel economics package can also now easily be undertaken so that one ties scientific uncertainty and economic uncertainty together for hydrocarbon exploration and identifies the global parameters dominantly influencing the combined economic/basin analysis system.
Inadequate Standards Currently Applied by Local Authorities to Determine Statutory Nuisance from LF and Infrasound
Authors: Guest Hazel
Published: September 2003

Knowledge of the latest results in Low Frequency Noise (LFN) and infrasound research are not being transmitted, either to government whose job it is to legislate on standards of noise and vibration, or to local authority officers whose job it is to look into complaints and enforce standards. The dismissal of complaints is frequently based on inappropriate techniques such as the application of A-weighting, a lack of understanding of vibration transmission including building resonance, and a lack of basic understanding about the perception of low frequencies by complainants, for instance the lowering of the lower audibility threshold arising from exposure.

This paper asks those involved in research to ensure that their relevant findings are more widely disseminated, along with advice to legislators and local authorities on measurement, information on LF and infrasound resonance in buildings, recommendations for appropriate standards to be used in assessing LF and infrasound as a Statutory Nuisance, and information about the effects of long-term exposure. There is a need for more research in situ into specific effects.
Assessments of Low Frequency Noise Complaints among the Local Environmental Health Authorities and a Follow-up Study 14 Years Later
Authors: Bengtsson Johanna , Waye Kerstin Persson
Published: September 2003

Interviews among a selection of 37 of the 289 Swedish local Environmental Health Authorities (EHA) were undertaken in order to assess the occurrence of complaints on low frequency noise. The study also aimed to evaluate whether the specific guidelines on low frequency noise, adopted in 1996, were used and how they performed when assessing low frequency noise. The results showed that most complaints of low frequency noise were due to noise from fan- and ventilation installations, amplified music, compressors and laundryrooms. According to 46% of the EHA, complaints due to low frequency noise had increased during the last two years, while the same percentage reported no change. When assessing low frequency noise, 62% of the EHA reported that the specific guidelines on low frequency noise based on third octave band analysis performed better or much better compared to the previous A-weighted guideline, and only one EHA thought it performed worse.
An Investigation of the Perception Thresholds of Band-Limited Low Frequency Noises: Influence of Bandwidth
Authors: Matsumoto Yasunao , Takahashi Yukio , Maeda Setsuo , Yamaguchi Hiroki , Yamada Kazuhiro , Subedi Jishnu K
Published: September 2003

Perception thresholds of complex low frequency noises have been investigated in a laboratory experiment. Sound pressure levels that were just perceptible by subjects were measured for three complex noises and three pure tones. The complex noises had a flat constant spectrum over the frequency range 2 to 10, 20, or 40 Hz and decreased at 15 dB per octave at higher frequencies. The frequencies of the pure tones used in this study were 10, 20 and 40 Hz. The perception thresholds were obtained using an all-pass filter, one-third octave band filters, and the G frequency weighting defined in ISO 7196. The G-weighted sound pressure levels obtained were compared with 100 dB which is described in ISO 7196 as the G-weighted level corresponding to the threshold of sounds in the frequency range 1 to 20 Hz. The perception thresholds of the pure tones measured in this study were comparable to the results available in various previous studies. The one-third octave sound pressure levels obtained for the thresholds of the complex noises appeared to be lower than the measured thresholds of the pure tones. The G-weighted sound pressure levels obtained for the thresholds of the complex noises appeared to be lower than 100 dB.
Loudness of Structure-Borne Sound Heard Directly by Ear Put on Vibrating Structure
Authors: Fujimoto Takuya
Published: September 2003

Putting an ear close to a vibrating structure like a wall or a floor, we are able to hear structure-borne sounds clearly, but the loudness of such sounds has never been studied quantitatively. In this study, subjective experiments were carried out in order to obtain the relationship between loudness and the vibration amplitude of the ear's contact surface at low audible frequencies. The main result of this study is that the loudness of a structure-borne sound is almost equal to that of an air-borne sound with a sound pressure level 20 dB higher than the vibration velocity level (ref=5×10−8 m/s) of the surface. According to this result, the loudness of the structure-borne sound heard directly can be evaluated as a sound pressure level derived from the measured vibration amplitude of the structure.
A Study on a Controller to Suppress Periodic Speed Variation
Authors: Kosaka Manabu , Uda Hiroshi , Bamba Eiichi
Published: September 2003

This paper is concerned with a practical controller to suppress the periodic speed variation of a motor. Speed variation in a pump, a compressor or a wheel of an electric vehicle causes vibration and noise, which shorten the life of the machine. Although repetitive control can suppress the speed variation, there are the following problems:

If a reference velocity changes, the period of the speed variation changes and the effect of the suppression is reduced. The tuning parameters are difficult to tune.

In the case where a low-resolution angle sensor is used, the output of the controller to suppress the speed variation becomes pulse-shaped and causes harmonic ripples that increase energy consumption. In order to eliminate the harmonic ripples, we propose a controller of which the output is interpolated with a sine wave.
A Finite Element Model for the Analysis of Wrinkled Membrane Structures
Authors: Ziegler René , Wagner Werner , Bletzinger Kai-Uwe
Published: September 2003

The problem of wrinkling in membrane structures has been a field of research since the publication of the tension field theory for plane structures. Significant progress in wrinkling analysis of arbitrarily shaped membranes has been made with the development of numerical methods. In the paper we present the enhancements of a standard finite element membrane formulation which allow to depict the wrinkles within the plane of the structure. A mathematical-numerical method is derived, which describes a valid stress state by minimising the differences in the stress density function while observing the wrinkling conditions. A consistent linearization of the proposed algorithms ensures quadratic convergence behaviour.
Tensegrity Structures Prestressability Investigation
Authors: Sultan Cornel , Skelton Robert
Published: September 2003

A methodology for the investigation of tensegrity structures prestressability is presented. The methodology is aimed at identifying particular prestressable configurations for which the prestressability conditions can be expressed in a simple form. Examples of the application of the methodology to a class of tensegrity structures, called tensegrity towers, are presented.
“Premit” System for Space Reticulated Structures
Authors: Dipaola Vincenzo , Prete Giuseppe
Published: September 2003

This is the first of three papers where we present the applicable potential of an original construction process for steel space grids, named PREMIT System. After a general introduction, we explain the geometrical and structural characteristics of the proposed System. We carry out a morphological study of the principal typological schemes to which it is possible to extend the applicable field of the System. Moreover, we deduce some useful criteria for the static-economic valuation through a comparative analysis among the more frequently employed geometrical shapes.
“Premit” System for Space Reticulated Structures
Authors: Dipaola Vincenzo , Prete Giuseppe
Published: September 2003

This is the second of three papers where we present the applicable potential of an original construction process for steel space grids, named PREMIT System. Here we explain the geometrical and structural characteristics of the bolted version of the proposed System. Moreover we carry out the static analysis of basic components as well as presenting parametric modelling. A codification and an inventory of technical solutions, useful to satisfy the design requirements of a wide application case study, are formulated. Finally, in the last section, the most important System's prerogatives are Briefly exposed.
“Premit” System for Space Reticulated Structures
Authors: Dipaola Vincenzo , Prete Giuseppe
Published: September 2003

This is the third of three papers where we present the application potential of an original structural process for steel space grids, named PREMIT System. Here we explain the geometrical and structural characteristics of the welded version of the proposed System. Moreover we carry out the static analysis of structural components and we present a parametric modelling. Finally a codification and an inventory of technical solutions, useful to satisfy the design requirements of a wide applicative case study, are proposed. In the Appendix we present two System's variants, valid for both the bolted and the welded versions, with the aim to achieve appreciable economies in terms of materials and manufacturing.
A Probabilistic Model for Simulating Long-Term Wind-Power Output
Authors: Kennedy Scott , Rogers Peter
Published: September 2003

This paper describes a chronological wind-plant simulation model for use in long-term energy resource planning. The model generates wind-power time series of arbitrary length that accurately reproduce short-term (hourly) to long-term (yearly) statistical behaviour. The modelling objective and methodology differ from forecasting models, which focus on minimizing prediction error. In the present analysis, periodic cycles are isolated from historical wind-speed data from a known local site and combined with a first-order autoregressive process to produce a wind-speed time series model. Corrections for negative wind-speed values and spatial smoothing for geographically disperse wind turbines are discussed. The resulting model is used to simulate the output from a hypothetical offshore wind-plant south of Long Island, New York. Modelled differences of power output between individual turbines result from wind speed variability; wake effects are not considered in this analysis.
Power Augmentation of a HAWT by Mie-type Tip Vanes, considering Wind Tunnel Flow Visualisation, Blade-Aspect Ratios and Reynolds Number
Authors: Shimizu Yukimaru , Ismaili Edmond , Kamada Yasunari , Maeda Takao
Published: September 2003

Wind tunnel results are reported concerning the effects of blade aspect ratio and Reynolds number on the performance of a horizontal axis wind turbine (HAWT) with Mie-type1 tip attachments. The flow behaviour around the blade tips and the Mie-type tip vanes is presented. Detailed surface oil film visualization and velocity measurements around the blade tips, with and without Mie vanes, were obtained with the two-dimensional, Laser-Doppler Velocimetry method. Experiments were performed with rotors having blades with different aspect ratio and operating at different Reynolds numbers. The properties of the vortices generated by the Mie vanes and the blade tips were carefully studied. It was found that increased power augmentation by Mie vanes is achieved with blades having smaller aspect ratio and smaller Reynolds number.
Innovative Reactive Power Saving in Wind-driven Grid-connected Induction Generators Using a Delta-Star Stator Winding: Part II, Estimation of Annual Wh and VARh of the Delta-Star Generator and Comparison with Alternative Schemes
Authors: Kumaresan N. , Subbiah M.
Published: September 2003

This paper considers constant-speed electricity generation using induction generators. Taking typical wind-farm site data, a case study allows performance evaluation of the previously proposed delta-star induction generator feeding power to the grid. By making an annual estimation of energy fed to the grid and reactive power drawn from the grid, advantages of this multi-stage generator are shown. A method for studying the effect of variation in wind speed pattern, on the annual reactive power drawn from the grid is indicated. A performance comparison with some other wind-driven constant-speed induction generator systems is also made.
Grid Tripping and Re-connection: Full-scale Experimental Validation of a Dynamic Wind Turbine Model
Authors: Raben Niels , Donovan Martin Heyman , Jørgensen Erik , Thisted Jan , Akhmatov Vladislav
Published: September 2003

An experiment with tripping and re-connecting a MW wind turbine generator was carried out at the Nøjsomheds Odde wind farm in Denmark. The experimental results are used primarily to validate the shaft system representation of a dynamic wind turbine model. The dynamic wind turbine model is applied in investigations of power system stability with relation to incorporation of large amounts of wind power into the Danish power grid. The simulations and the measurements are found to agree. The experiment was part of a large R&D program started in Denmark to investigate the impact of the increasing capacity of wind power fed into the Danish power grid.
Twelve Years Energy Production Assessment of Greek State Wind Parks
Authors: Kaldellis J.K. , Vlachou D.S. , Paliatsos A.G.
Published: September 2003

In 1982, the Greek State started an ambitious wind energy exploitation program for that period, via the State owned Public Power Corporation. Now this 20 year effort faces serious obstacles and drawbacks, with an installed wind power capacity of only 37 MW. This paper analyses the life-long energy production of State owned wind power installations, with respect to the available wind speed data. A significant result is the erratic time-variation of the wind power production, not justified by the corresponding wind speed changes. In addition, the technical availability of most State wind parks has been rather low, despite significant improvement during the last five years. The overall conclusions have importance within the new liberalized European electricity market.
Experimental Study of a Pinwheel-Type Wind Turbine
Authors: Nemoto Yasuyuki , Ushiyama Izumi
Published: September 2003

Pinwheels have been familiar as toys for hundreds of years. Not only do they have an attractive appearance, they can also be fabricated from just one piece of plate. Application is possible, e.g. for education and architectural design. The purpose of this paper is to clarify the characteristics and to determine the optimum design configuration of pinwheel type wind turbines. The authors fabricated the test rotors with various shapes and carried out the experiment in a wind tunnel. As a result, the following facts were obtained: (1) Power coefficient with the traditional 4 blades has, CPmax = 0.17 at λ = 2. (2) High tip speed is obtained by cutting the frontal area of pinwheel. Tip speed ratio at no load can be easily changed from λ = 3 to 6 by changing the cutting area. Maximum power coefficient CPmax = 0.22 was obtained at tip speed ratio λ = 3.5. (3) Increased torque is obtained by cutting the edge area of the pinwheel. Tip speed ratio at no load can be easily changed from λ = 2 to 3, and torque coefficient can be easily changed from CQmax = 0.15 to 0.25, by changing the cut area.
CO2 Recovery and Reuse in the Energy Sector, Energy Resource Development and Others: Economic and Technical Evaluation of Large-Scale Co2 Recycling
Authors: Kikuchi Ryunosuke
Published: September 2003

Climate change caused by greenhouse gases is receiving worldwide attention. CO2 (carbon dioxide) emission accounts for 80% of greenhouse gas emissions. The current measures against emission of CO2 are mainly control of emissions, sequestration and fixation, but CO2 emission decreased by only 1.6% in Europe during the past decade. CO2 recovery and reuse may offer new options for the greenhouse gas strategy. CO2 recovery technology such as the amine process is economically and technically feasible for industrial-scale application, and the recovered CO2 can be utilized for energy production, development of new energy resources, agriculture, etc. Recycling of CO2 on a large scale is discussed in this paper.
EU Emission Trading: Starting with Carbon Dioxide
Authors: Vesterdal Morten , Svendsen Gert Tinggaard
Published: September 2003

The Commission of the European Union wants to start a limited emission trading scheme by 2005 within the Community to enable “learning-by-doing” prior to the Kyoto Protocol. This is to accomplish the desired 8% target level for six different greenhouse gases. However, in the EU it is not clear whether all the six relevant greenhouse gases or only CO2 should be traded. What is the simplest and most practicable solution? We argue in favour of the latter option for three main reasons: the possible dominating global warming potential of CO2, expected future developments in CO2 emissions and the fact, that CO2 is the pollutant most easily monitored.
A New Interpretation of Depth—Age Profiles
Authors: Townsend P. D. , Parish R. , Rowlands A. P.
Published: September 2003

Dosimetry and other techniques provide depth–age profiles in materials as diverse as sediments and ice. A frequent characteristic feature of these plots is a non-linear curve with a foreshortened depth scale. Whilst the age analyses from the dosimetry do not present a problem, many authors have made subsequent assumptions on the basis of the curve shape with respect to climate and environmental changes. Such claims should be strongly questioned, as by using a model which includes the effects of compaction, most of the original curves transform into linear plots corresponding to constant depositional rates. The corrections and the implications for models of climate change are discussed.
Economics, Emissions Scenarios and the Work of the IPCC
Authors: Castles Ian , Henderson David
Published: September 2003

This article restates and extends our critique of the economic and statistical work of the Intergovernmental Panel on Climate Change (IPCC), including in particular the Special Report on Emissions Scenarios (SRES). We respond to the article in the previous issue of Energy and Environment, in which 15 authors associated with the SRES argued against the case we had made there. We give reasons for rejecting their view that market exchange rates (MERs) should be used in deriving cross-country measures of economic growth, and note that in its handling of this and related issues they and others involved in the IPCC process are not professionally representative. We show how the mistaken use of MER-based comparisons, together with questionable assumptions about ‘closing the gap’ between rich countries and poor, have imparted an upward bias to projections of economic growth in developing countries, and hence to projections of total world emissions. We list actions that could be taken now, in the context of the IPCC's Fourth Assessment Review which is about to be launched, to set the economic and statistical aspects of the Review on a sounder basis. We argue that it is high time for ministries of economics and finance to inform themselves about the IPCC process and to become involved in it.
Restoration of Open Pit Lignite Mining in the Former GDR: Lessons to Belearnt from Zwenkau
Authors: Wiegand U. , Schreck P. , Schreiter P. , Lerche I. , Glaesser W.
Published: September 2003

The interactions have been investigated between the near-surface sediments of the sediment dumping at the Zwenkau open pit (used for extraction of lignite) and the produced mining water. These environmental impacts are the legacy of the energy policy of the former GDR. The pyrite oxidation that takes place in the overburden sediments causes the formation of an oxidation front and the pH-value of sediments falls to about 2 to 3 very soon after deposition. The primary mineral contents are destroyed and a considerable number of elements are mobilized that remain locally in the sediment pores. Because of the very weak seepage, rainfall remains in the alluvial areas as dump lakes. The dump lakes are very acidic because the rainwater transports the mobilized elements from the surface. Autochthonous and allochthonous formations of secondary minerals have been observed and analysed. A continuously ongoing interaction of exogenous and endogenous effects hinders the hydrological and geochemical equilibrium stabilisation. What to do with such a “moonscape” is considered in the conclusions.
Effect of Acoustics on NoX Emission in Premixed Flame, Experimental Study
Authors: Tashtoush Ghassan
Published: September 2003

The effect of acoustic frequency on pollutants emissions from a premixed gas combustor has been investigated. A significant decrease (down to 61.5%) in nitrogen oxide (NO) emissions was observed in the presence of acoustic oscillation (two opposite square waves) in a premixed flame. Although the overall production of the pollutants is reduced, the reduction rate depends on the frequency and the direction of the acoustic field. It is shown that the acoustic effect can be considered as a possible alternative to flue gas reburn technology to achieve the same or even better effectiveness in NOx and CO pollutants reduction with much less cost.
Packed-Bed Removal of Copper and Zinc Ions Using Chemically-Treated Chicken Feathers
Authors: Al-Asheh Sameer , Banat Fawzi
Published: September 2003

In this work, the sorption of copper by chemically treated chicken feathers was tested via packed-bed column. Chicken feathers were selected as adsorbent based on its high availability as environmental waste. The alkaline-treated chicken feathers column showed good sorption capacity toward copper and zinc ions. It was proved that an increase in metal concentration or flow rate of the influent solution shortens the break-through time. The break-through time increased with the bed depth. The break-through time occurred earlier when zinc was passed through the column rather than copper, but the bed capacity was higher for the later than for the former. The key process design parameters, which could serve as a basis for sorption process scale up, were calculated by applying the Bed-Depth-Service-Time (BDST) model to the experimental data.
Foreseeable Health Risk of Electric and Magnetic Field Residential Exposures
Authors: Habash Riadh W. Y.
Published: September 2003

Exposure to electric and magnetic fields (EMFs) emanating from the generation, distribution and utilization of electricity is widespread. The major debate in recent years has been the possibility that EMFs influence various effects on the human body especially development of cancer. Epidemiologists were the first scientists to publicize this fact through human population studies. Current investigations into this topic split up over diverse areas of research. This paper provides a review of information on health risk of EMF residential exposure. Four major areas have been considered for evaluating the possible risks with emphasis on recent studies. These include safety standards for EMFs, residential field measurement surveys, biological and epidemiological studies of diseases with foreseeable association with EMFs including childhood leukemia, breast cancer, and pregnancy adverse outcomes. On the basis of review findings, it is difficult to provide a robust conclusion about health risk of EMFs, raising the significance of researching this area further. No policy advise is offered, however, as a voluntary precautionary measure, public health professionals, regulatory authorities, standard setters, electric utilities, and individuals are encouraged to advocate minimizing EMF exposures wherever possible.
An Appraisal of the Quality of Referral Letters from General Dental Practitioners to a Temporomandibular Disorder Clinic
Authors: O'Donovan Annette E , Ager Paul M , Davies Stephen J , Smith Philip W
Published: September 2003

Aim

To assess the usefulness of referral letters from general dental practitioners (GDPs) to a clinic seeing referrals related to temporomandibular disorders.

Design

A retrospective analysis of all referral letters received by the TMD clinic at Manchester Dental Hospital over a ten-week period.

Methods

The new patient referral letters to the TMD clinic were examined against suggested criteria of 16 points of information considered to be useful by clinicians working in the clinic. The letters were then assessed using a quality scale based on the level of useful information given in the letter, and using this scale, classified into groups of ‘very helpful’, ‘some help’ or ‘a little helpful’.

Results

Out of the 100 letters analysed, the majority (94) proved to be a ‘little helpful’ for the TMD clinician; that is to say, the letter included only 0–4 points (out of 16) regarded as important information for the specialist. The maximum number of points of information contained in a letter was nine. No letters were categorised as ‘very helpful’ for the clinician, and only 6% of the referral letters were considered to provide some help (5–12 points).

Conclusions

During the period of the study, in general, referral letters to the TMD clinic concerned contained insufficient information. The introduction of a referral pro forma, produced by the TMD clinic, and guidelines might improve the quality of referrals.
Current Issues in Dental Practice Management Part 3. Attracting and Keeping Patients
Authors: Newsome Philip RH
Published: September 2003

This paper, the third in a series of articles exploring some of the management issues facing dentists today, examines the importance of maintaining a motivated, well-trained and properly rewarded staff team.
Drug Profile of Adult Patients Attending Five General Dental Practices in Merseyside
Authors: Brindley Maria J , Longman Lesley P , Randall Christine , Field E Anne
Published: September 2003

Objective

To evaluate the drug profile of patients attending general dental practice and to assess the significance of this for the provision of dental care.

Design and setting

Prospective study of adult patients attending five general dental practices in Merseyside.

Materials and methods

Patients were questioned about prescribed medication. The data were analysed to assess any potential oral side-effects, pertinent drug interactions, or potential complications of dental treatment.

Results

A total of 1103 patients were recruited; of these, 287 (26%) were taking systemic medication.

Conclusion

Approximately a quarter of dental patients attending for routine dental care were taking prescribed medication. The majority of these drugs have significant implications for the general dental practitioner.
Evaluation of a Pilot Hands-on Course in Surgical Dentistry for Primary Care Dental Practitioners in Oxfordshire
Authors: John Jeyanthi H , Thomas David , Richards Derek , Juniper Richard , Henderson Stephen
Published: September 2003

Objectives

To evaluate the impact of a course in surgical dentistry on the confidence of 32 general dental practitioners, each of whom attended a one-day hands-on course.

Design

Questionnaire survey.

Setting

General dental practitioners attending a course on surgical dentistry, which was run over a day, for eight participants per day.

Results

The course was rated highly by participants. The hands-on component was particularly well received. Confidence scores increased for several surgical procedures, particularly for removal of impacted teeth and for apicectomies of single-rooted teeth. There were concomitant decreases in the proportion of participants who said that they would refer patients requiring these surgical procedures. Confidence scores remained low for complex procedures such as molar apicetomies. However, it would be appropriate to refer these cases for specialist care.

Conclusions

The results of this pilot study indicated that a course in surgical dentistry was successful in increasing the confidence of a small group of general dental practitioners. More research is needed to determine whether this is the most effective way of helping practitioners maintain and improve skills and confidence in surgical dentistry.
Reflections on Teaching Dental Ethics to Vocational Dental Practitioners in London in 2002
Authors: Gordon Edgar R
Published: September 2003

In autumn 2002, the five London general dental practice vocational training schemes were the subject of focus group analysis after a session on dental ethics. The participants discussed a number of ethical dilemmas based on copies of original records and correspondence with names deleted. During the final part of the session, participants’ perceptions and opinions on the teaching of ethics were explored. This provided interesting insights into their knowledge of and attitudes toward ethics and the professional/business interface.
Ab Initio Determination of Edge Surface Structures for Dioctahedral 2:1 Phyllosilicates: Implications for Acid-Base Reactivity
Authors: Bickmore Barry R. , Rosso Kevin M. , Nagy Kathryn L. , Cygan Randall T. , Tadanier Christopher J.
Published: September 2003

The atomic structure of dioctahedral 2:1 phyllosilicate edge surfaces was calculated using pseudopotential planewave density functional theory. Bulk structures of pyrophyllite and ferripyrophyllite were optimized using periodic boundary conditions, after which crystal chemical methods were used to obtain initial terminations for ideal (110)- and (010)-type edge surfaces. The edge surfaces were protonated using various schemes to neutralize the surface charge, and total minimized energies were compared to identify which schemes are the most energetically favorable. The calculations show that significant surface relaxation should occur on the (110)-type faces, as well as in response to different protonation schemes on both surface types. This result is consistent with atomic force microscopy observations of phyllosilicate dissolution behavior. Bond-valence methods incorporating bond lengths from calculated structures can be used to predict intrinsic acidity constants for surface functional groups on (110)- and (010)-type edge surfaces. However, the occurrence of surface relaxation poses problems for applying current bond-valence methods. An alternative method is proposed that considers bond relaxation, and accounts for the energetics of various protonation schemes on phyllosilicate edges.
Monte Carlo and Molecular Dynamics Simulation of Uranyl Adsorption on Montmorillonite Clay
Authors: Zaidan Omar F. , Greathouse Jeffery A. , Pabalan Roberto T.
Published: September 2003

We performed Monte Carlo and molecular dynamics simulations to investigate the interlayer structure of a uranyl-substituted smectite clay. Our clay model is a dioctahedral montmorillonite with negative charge sites in the octahedral sheet only. We simulated a wide range of interlayer water content (0 mg H2O/g clay — 260 mg H2O/g clay), but we were particularly interested in the two-layer hydrate that has been the focus of recent X-ray absorption experiments. Our simulation results for the two-layer hydrate of uranyl-montmorillonite yield a water content of 160 mg H2O/g clay and a layer spacing of 14.66 Å. Except at extremely low water content, uranyl cations are oriented nearly parallel to the surface normal in an outer-sphere complex. The first coordination shell consists of five water molecules with an average U-O distance of 2.45 Å, in good agreement with experimental data. At low water content, the cations can assume a perpendicular orientation to include surface oxygen atoms in the first coordination shell. Our molecular dynamics results show that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:c="http://cambridge.org/core/content" xmlns:core="http://cambridge.org/core" xmlns:m="http://cambridge.org/core/metadata" xmlns:cup="http://contentservices.cambridge.org" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:mnf="http://cambridge.org/core/manifest">UO2(H2O)52+ complexes translate within the clay pore through a jump diffusion process, and that first-shell water molecules are exchangeable and interchangeable.
Characterization of Microbially Fe(III)-Reduced Nontronite: Environmental Cell-Transmission Electron Microscopy Study
Authors: Kim Jin-wook , Furukawa Yoko , Daulton Tyrone L. , Lavoie Dawn , Newell Steven W.
Published: September 2003

Microstructural changes induced by the microbial reduction of Fe(III) in nontronite by Shewanella oneidensis were studied using environmental cell (EC)-transmission electron microscopy (TEM), conventional TEM, and X-ray powder diffraction (XRD). Direct observations of clays by EC-TEM in their hydrated state allowed for the first time an accurate and unambiguous TEM measurement of basal layer spacings and the contraction of layer spacing caused by microbial effects, most likely those of Fe(III) reduction. Non-reduced and Fe(III)-reduced nontronite, observed by EC-TEM, exhibited fringes with mean d001 spacings of 1.50 nm (standard deviation, σ = 0.08 nm) and 1.26 nm (σ = 0.10 nm), respectively. In comparison, the same samples embedded with Nanoplast resin, sectioned by microtome, and observed using conventional TEM, displayed layer spacings of 1.0–1.1 nm (non-reduced) and 1.0 nm (reduced). The results from Nanoplast-embedded samples are typical of conventional TEM studies, which have measured nearly identical layer spacings regardless of Fe oxidation state. Following Fe(III) reduction, both EC- and conventional TEM showed an increase in the order of nontronite selected area electron diffraction patterns while the images exhibited fewer wavy fringes and fewer layer terminations. An increase in stacking order in reduced nontronite was also suggested by XRD measurements. In particular, the ratio of the valley to peak intensity (v/p) of the 1.7 nm basal 001 peak of ethylene glycolated nontronite was measured at 0.65 (non-reduced) and 0.85 (microbially reduced).
Maghemite Formation in Burnt Plant Litter at East Trinity, North Queensland, Australia
Authors: Grogan Kirsty L. , Gilkes Robert J. , Lottermoser Bernd G.
Published: September 2003

Evidence for the formation of maghemite from goethite due to a bushfire on acid sulfate soil at East Trinity, Australia, is presented. Oxidation of pyrite-bearing acid sulfate soils led to precipitation of goethite-impregnated leaf litter. During a major bushfire, goethite with a crystal size calculated from broadening of the 110 reflection of ∼9 nm was converted to microcrystalline maghemite (size 12 nm, 220 reflection) and hematite (17 nm, 104 reflection) in a matrix of partly combusted plant litter. Replication of this natural formation of maghemite from goethite was achieved in the laboratory by burning goethite-impregnated leaf litter.
Cd-Substituted Goethites — A Structural Investigation by Synchrotron X-ray Diffraction
Authors: Huynh Trang , Tong Andrew R. , Singh Balwant , Kennedy Brendan J.
Published: September 2003

The structural and physical effects of partially substituting Cd for Fe in goethite have been investigated. The solubility of Cd2+ in goethite is ∼10 mol.%, i.e. Fe0.905Cd0.095OOH. The structures of the substituted goethites have been refined, using the Rietveld method, from synchrotron X-ray powder diffraction data. There is a progressive increase in the size of the unit-cell parameters and unit-cell volume, upon the incorporation of much larger Cd2+ ion (0.95 Å) compared with Fe3+ (0.645 Å) in the goethite structure, together with a reduction in crystallinity. Transmission electron microscopy measurements confirm the crystallite size decreases as the Cd2+ content increases in goethite structure.
113Cd, 1H MAS NMR and FTIR Analysis of Cd2+ Adsorption on Dioctahedral and Trioctahedral Smectite
Authors: Di Leo Paola , Cuadros Javier
Published: September 2003

Dioctahedral and trioctahedral smectites of very low Fe contents were exchanged with Ca (0.8 N CaCl2) and then with Cd (0.004–0.2 N CdCl2), resulting in the approximate Ca/Cd interlayer compositions 100/0, 75/25, 50/50 and 0/100. The samples were analyzed using 113Cd and 1H MAS NMR spectroscopy, at different hydration states, and by FTIR using films oriented at 90 and 45° to the infrared beam. When adsorbed from low-concentration CdCl2 solutions, as in this study, Cd is in the smectite interlayer as Cd2+, surrounded by water molecules. In smectite specimens with no tetrahedral charge, Cd occupies one single site in the center of the interlayer along the c axis but in smectite with tetrahedral charge, the basal oxygen atoms with excess negative charge interact with some of the Cd atoms more strongly, generating a second site in which Cd is displaced from the center of the interlayer and closer to those oxygen atoms. The 1H NMR study showed protons from hydration water and smectite hydroxyls and showed that both have more than one component. The FTIR and 1H NMR experiments indicate that Cd interacts with hydroxyl groups through one of the solvating water molecules in the first coordination sphere. Cadmium retains water molecules bridging Cd and OH groups even at low hydration states. Comparison with previous studies shows that, when adsorbed from high-concentration CdCl2 solutions, Cd species other than Cd2+ are present in sufficient quantities to enter the interlayer and create a different Cd-water complex, seemingly displacing Cd2+ from the center of the interlayer.