bluuebunny/crossref_metadata_2025 huggingface dataset:
Review: Deep brain stimulation in Parkinson’s disease
Authors: Groiss S.J. , Wojtecki L. , Südmeyer M. , Schnitzler A.
Published: September 2009

During the last 15 years deep brain stimulation (DBS) has been established as a highly-effective therapy for advanced Parkinson’s disease (PD). Patient selection, stereotactic implantation, postoperative stimulator programming and patient care requires a multi-disciplinary team including movement disorders specialists in neurology and functional neurosurgery. To treat medically refractory levodopa-induced motor complications or resistant tremor the preferred target for high-frequency DBS is the subthalamic nucleus (STN). STN-DBS results in significant reduction of dyskinesias and dopaminergic medication, improvement of all cardinal motor symptoms with sustained long-term benefits, and significant improvement of quality of life when compared with best medical treatment. These benefits have to be weighed against potential surgery-related adverse events, device-related complications, and stimulus-induced side effects. The mean disease duration before initiating DBS in PD is currently about 13 years. It is presently investigated whether the optimal timing for implantation may be at an earlier disease-stage to prevent psychosocial decline and to maintain quality of life for a longer period of time.
Focus on Scaffolding Language and Sequential Units During Choral Instruction
Authors: Freer Patrick K.
Published: September 2009

The purpose of the study reported in this article was to investigate the instructional discourse of two middle school choral music teachers videotaped during a total of 24 classroom visits. The findings indicate that teacher attention to complete sequential units of instruction (teacher presentation, student interaction, teacher feedback) may encourage the employment of scaffolding language (language that supports student learning). A focus on scaffolding language corresponded to a decrease in the completion of sequential units of instruction. Choral teachers seeking to foster a constructivist-oriented rehearsal environment may find it advantageous to focus attention on the completion of sequential units of instruction. Similarly, teachers of collegiate methods classes may wish to draw students’ attention to complete sequential units as a precursor to exploring the application of constructivist theory to ensemble rehearsal technique.
Three-dimensional FEM analysis of laser shock peening of aluminium alloy 2024-T351 thin sheets
Authors: Ivetic G
Published: September 2009

Laser shock peening is a relatively recent technique that introduces compressive residual stresses in metallic structures, improving fatigue, corrosion and wear resistance of treated materials. The purpose of this work is to evaluate numerically the effect of laser shock peening on thin sheets, since most of the numerical analyses available in the literature deal with semi-infinite body assumption, which disregards the reflection of shock waves from the back side of the treated specimen. This phenomenon should be considered when dealing with sheets used for thin walled constructions, for cases in which there is no possibility of using the back-up support, a solid plate in the contact with the backside of the treated sample that limits the wave reflection and deformations. Different set-ups of laser shock peening process are evaluated and an optimal set of parameters is suggested for a possible real structure application.
Effect of magnetic field on solidification structure of a centrifugal cast high speed steel roll
Authors: Zhang X. D. , Liu W. , Li Q. L. , Godfrey A. , Liu Q.
Published: September 2009

The electromagnetic field exerted during solidification of a centrifugal cast high speed steel roll causes a marked variation in the structure. The type, size, distribution and volume fraction of carbides change with increasing magnetic field intensity. The appropriate external magnetic field (0·15 T in the present study) can refine carbides, break down carbides’ network on grain boundaries, make some carbides form in grains, distribute carbides more homogeneously on grain boundaries or in grains and improve overall bulk hardness. The application of external magnetic field can also refine grains, reduce retained austenite and improve matrix hardness. It can be expected that through inducing an appropriate external magnetic field during centrifugal casting these changes can give an improvement of properties of HSS rolls, such as wear resistance and thermal fatigue properties.
Precipitation of secondary phases in super duplex stainless steel ZERON100 isothermally aged
Authors: Calliari I , Pellizzari M , Ramous E
Published: September 2009

In the present paper the results of secondary phases determination and quantification in ZERON100 duplex steel, heat treated at 850–1000°C for 180–2400 s, are presented. During the isothermal heat treatments, at 850°C, the χ phase is the only phase to precipitate at α/ γ boundaries and triple points, while at 900 and 950°C, χ phase is the first phase to precipitate after 180 s, followed by σ phase 300 s later. At all the temperatures the total amount of secondary phases is ∼3 after <600 s aging.
Homeostasis of dendritic cells in lymphoid organs is controlled by regulation of their precursors via a feedback loop
Authors: Hochweller Kristin , Miloud Tewfik , Striegler Jörg , Naik Shalin , Hämmerling Günter J. , Garbi Natalio
Published: September 2009

Dendritic cells (DCs) are key coordinators of the immune response, governing the choice between tolerance and immunity. Despite their importance, the mechanisms controlling the size of the DC compartment are largely unknown. Using a mouse model allowing continuous DC depletion, we show that maintenance of DC numbers in spleen is an active process mediated by Flt3-L–dependent regulation of precursor differentiation into DCs, rather than by changes in proliferation of the differentiated DCs. In particular, the frequency and differentiation potential of intrasplenic DC precursors increased in response to reduced DC numbers. Levels of Flt3-L, a cytokine required for DC differentiation, increased in the blood after DC depletion and returned to normal levels once the DC compartment filled up again. Our data suggest a feedback regulation of DC homeostasis whereby reduction of the DC pool size promotes differentiation of their precursors, via increased Flt3-L availability. This mechanism is different to those known for other immune cell types, such as the B- and T-cell compartments, whereby lymphopenia induces proliferation of already differentiated lymphocytes.
The thymus-independent immunity conferred by a pneumococcal polysaccharide is mediated by long-lived plasma cells
Authors: Taillardet Morgan , Haffar Ghina , Mondière Paul , Asensio Marie-Jeanne , Gheit Hanane , Burdin Nicolas , Defrance Thierry , Genestier Laurent
Published: September 2009

It was recently shown that bacterial thymus-independent (TI) antigens confer long-lasting immunity and generate memory B lymphocytes. However, reactivation of TI memory B cells is repressed in immunocompetent mice, thus raising the issue of the mechanism whereby TI vaccines confer immune protection. Here, we propose an explanation to this apparent paradox by showing that a Streptococcus pneumoniae capsular polysaccharide (PS) generates long-lived bone marrow (BM) plasma cells which frequency can be increased by CpG oligodeoxynucleotides (ODNs). The adjuvant effect of CpG ODNs on the PS3 Ab response is directly targeted to B cells and does not involve B-1a cells. We also demonstrated that BM plasma cells generated in response to the thymus-dependent (TD) form of the PS vaccine have a higher secretion capacity than those produced after immunization with the CpG-adjuvanted PS vaccine. Finally, we show that the PS-specific BM plasma cell compartment is sufficient to confer full protection of vaccinated mice against S pneumoniae infection. Altogether, our results show that TI antigens like their TD counterparts can generate both the lymphoid and the plasma cell component of B-cell memory. They also provide a framework for the improvement and widespread usage of TI vaccines.
Intracranial hemorrhage (ICH) in children with immune thrombocytopenia (ITP): study of 40 cases
Authors: Psaila Bethan , Petrovic Aleksandra , Page Lemke K. , Menell Jill , Schonholz Matthew , Bussel James B.
Published: September 2009

Intracranial hemorrhage (ICH) is a rare but devastating complication of childhood immune thrombocytopenia purpura (ITP). A survey of ICH from 1987 to 2000 identified cases of ICH in childhood ITP in the United States. Forty patients with ICH and 80 matched ITP control subjects were accrued. The estimated incidence of ICH was 0.19% to 0.78%. Platelet counts were less than 20 × 109/L in 90% and less than 10 × 109/L in 75% of children with ICH. Eighteen (45%) children developed ICH within 7 days of diagnosis of ITP; for 10 of these, ICH was the presenting feature of ITP. Twelve (30%) children had chronic ITP. Head trauma and hematuria were the most prominent features associated with ICH, identified in 33% and 22.5% of the patients with ICH and 1 and none of the controls (both P < .001). Bleeding beyond petechiae and ecchymoses was also linked to ICH. Mortality was 25%; a further 25% had neurologic sequelae. Strategies by which high-risk children could be identified were considered, and the costs of preventive combination treatment were estimated. Children with severe thrombocytopenia plus head trauma and/or hematuria appeared to be at particularly high risk of ICH. Aggressive treatment of these children may be appropriate.
Interim positron emission tomography scans in diffuse large B-cell lymphoma: an independent expert nuclear medicine evaluation of the Eastern Cooperative Oncology Group E3404 study
Authors: Horning Sandra J. , Juweid Malik E. , Schöder Heiko , Wiseman Gregory , McMillan Alex , Swinnen Lode J. , Advani Ranjana , Gascoyne Randy , Quon Andrew
Published: September 2009

Positive interim positron emission tomography (PET) scans are thought to be associated with inferior outcomes in diffuse large B-cell lymphoma. In the E3404 diffuse large B-cell lymphoma study, PET scans at baseline and after 3 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone were centrally reviewed by a single reader. To determine the reproducibility of interim PET interpretation, an expert panel of 3 external nuclear medicine physicians visually scored baseline and interim PET scans independently and were blinded to clinical information. The binary Eastern Cooperative Oncology Group (ECOG) study criteria were based on modifications of the Harmonization Criteria; the London criteria were also applied. Of 38 interim scans, agreement was complete in 68% and 71% by ECOG and London criteria, respectively. The range of PET+ interim scans was 16% to 34% (P = not significant) by reviewer. Moderate consistency of reviews was observed: κ statistic = 0.445 using ECOG criteria, and κ statistic = 0.502 using London criteria. These data, showing only moderate reproducibility among nuclear medicine experts, indicate the need to standardize PET interpretation in research and practice. This trial was registered at www.clinicaltrials.gov as #NCT00274924.
Complete genome sequence of the sugarcane nitrogen-fixing endophyte Gluconacetobacter diazotrophicus Pal5
Authors: Bertalan Marcelo , Albano Rodolpho , de Pádua Vânia , Rouws Luc , Rojas Cristian , Hemerly Adriana , Teixeira Kátia , Schwab Stefan , Araujo Jean , Oliveira André , França Leonardo , Magalhães Viviane , Alquéres Sylvia , Cardoso Alexander , Almeida Welington , Loureiro Marcio Martins , Nogueira Eduardo , Cidade Daniela , Oliveira Denise , Simão Tatiana , Macedo Jacyara , Valadão Ana , Dreschsel Marcela , Freitas Flávia , Vidal Marcia , Guedes Helma , Rodrigues Elisete , Meneses Carlos , Brioso Paulo , Pozzer Luciana , Figueiredo Daniel , Montano Helena , Junior Jadier , de Souza Filho Gonçalo , Martin Quintana Flores Victor , Ferreira Beatriz , Branco Alan , Gonzalez Paula , Guillobel Heloisa , Lemos Melissa , Seibel Luiz , Macedo José , Alves-Ferreira Marcio , Sachetto-Martins Gilberto , Coelho Ana , Santos Eidy , Amaral Gilda , Neves Anna , Pacheco Ana Beatriz , Carvalho Daniela , Lery Letícia , Bisch Paulo , Rössle Shaila C , Ürményi Turán , Rael Pereira Alessandra , Silva Rosane , Rondinelli Edson , von Krüger Wanda , Martins Orlando , Baldani José Ivo , Ferreira Paulo CG
Published: September 2009

Background

Gluconacetobacter diazotrophicus Pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. It has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins.

Results

Gluconacetobacter diazotrophicus Pal5 is the third diazotrophic endophytic bacterium to be completely sequenced. Its genome is composed of a 3.9 Mb chromosome and 2 plasmids of 16.6 and 38.8 kb, respectively. We annotated 3,938 coding sequences which reveal several characteristics related to the endophytic lifestyle such as nitrogen fixation, plant growth promotion, sugar metabolism, transport systems, synthesis of auxin and the occurrence of bacteriocins. Genomic analysis identified a core component of 894 genes shared with phylogenetically related bacteria. Gene clusters for gum-like polysaccharide biosynthesis, tad pilus, quorum sensing, for modulation of plant growth by indole acetic acid and mechanisms involved in tolerance to acidic conditions were identified and may be related to the sugarcane endophytic and plant-growth promoting traits of G. diazotrophicus. An accessory component of at least 851 genes distributed in genome islands was identified, and was most likely acquired by horizontal gene transfer. This portion of the genome has likely contributed to adaptation to the plant habitat.

Conclusion

The genome data offer an important resource of information that can be used to manipulate plant/bacterium interactions with the aim of improving sugarcane crop production and other biotechnological applications.
Alternate raft pathways cooperate to mediate slow diffusion and efficient uptake of a sphingolipid tracer to degradative and recycling compartments
Authors: Zhang Dawei , Manna Manoj , Wohland Thorsten , Kraut Rachel
Published: September 2009

Several cholesterol-dependent cellular uptake pathways involving microdomain-resident sphingolipids have been characterized, but little is known about what controls the further intracellular trafficking routes of those domains. Here, we present evidence that the uptake and intracellular trafficking of a recently described sphingolipid-binding probe, the sphingolipid binding domain (SBD) peptide, is mediated by two parallel cooperating mechanisms requiring flotillin, dynamin and cdc42, which act in concert to direct a distinct surface behavior and trafficking itinerary. Diffusion measurements of SBD at the cell surface by fluorescence correlation spectroscopy suggest that cdc42- and flotillin-associated uptake sites both correspond to domains of intermediate mobility, but that they can cooperate to form low-mobility, efficiently internalized domains. Interestingly, we find that the choice of uptake mechanism affects subsequent trafficking of SBD, as does cholesterol content. Interference with one or other uptake pathway acts as a toggle switch for the trafficking of SBD to recycling endosomes or endolysosomes, whereas both of these pathways are bypassed if cholesterol is reduced. The data are in accordance with a scenario in which SBD mirrors the trafficking response of raft-borne lipids towards a degradative or recycling target. In summary, we suggest that both the surface behavior of a cargo and its subsequent trafficking are determined by a combination of endocytic accessory proteins and the cholesterol content of different membrane compartments.
Finite-element and multivariate analyses of tension distribution and spinning parameter effects on a ring-spinning balloon
Authors: Mardani Mehrabad N , Safar Johari M , Aghdam M M
Published: September 2009

This study aims to investigate the effects of spinning parameters on the balloon tension and configuration. A novel experimental set-up was designed to measure the yarn tension at the pigtail. Experimental results were then used to implement boundary conditions in a multivariate analysis. Also, a finite-element (FE) code was used to predict the yarn balloon profile and stresses induced in the yarn. In particular, Coriolis acceleration and twist effects are considered on the model. It was observed that the equations governing the yarn path and the movement equation of twist in the yarn were completely dependent on each other. FE analysis revealed that while the Coriolis acceleration increases the tension in the yarn, it has little influence on the balloon configuration. Results of this study can be used to obtain optimized production parameters to increase the yarn quality and productivity.
Design and control of a high-acceleration precision positioning system using a novel flexible decoupling mechanism
Authors: Wang F , Zhao X , Zhang D , Wu Y , Shirinzadeh B , Tian Y
Published: September 2009

This article presents a high-acceleration precision positioning system to improve the efficiency and precision of micro-electro-mechanical system (MEMS) packaging. The positioning system is direct driven by linear voice coil actuators (LVCAs), and the mass and inertia of the motion system are significantly reduced by using a novel flexible decoupling mechanism based on flexure hinges. The decoupling principle of the mechanism is introduced, and the flexure hinges are designed by using an analytical method. Through dynamic analysis, the stiffness and preload of the spring are determined. With the aid of finite-element method and dynamic analysis, the influences of flexure hinges on the characteristics of the positioning system are investigated. Based on the dynamic characteristics of LVCA and the developed mechanism structure, the electromechanical coupled models are established. Minimum deadbeat response control strategy with a pre-filter is implemented to control the positioning system, and the parameters of the controller are optimized. Experimental tests are carried out to examine the characteristics of the positioning system. The results show that the positioning system provides good performances and satisfies the requirements of MEMS packaging operations.
Modelling of centrifugal-force-assisted abrasive flow machining
Authors: Walia R S , Shan H S , Kumar P
Published: September 2009

Centrifugal-force-assisted abrasive flow machining (CFAAFM) process has recently been tried as a hybrid machining process with the aim towards performance improvement of the abrasive flow machining process by applying centrifugal force on the abrasive-laden media with a rotating centrifugal-force-generating rod introduced in the workpiece passage. In the CFAAFM process, the surfaces are generated by erosion from random attack of abrasive particles. This article deals with the theoretical investigations into the mechanism of material removal in the CFAAFM process. Analytical model is developed to estimate the material removal during the process. A good correlation is found to exist between the theoretical results and the experimental data.
Application of ground-heat-source water thermal-storage with a heat-pump cooling and heating system
Authors: Lim K B , Lee S H , Lee C H
Published: September 2009

Ground-source heat pumps (GSHPs) are attractive alternatives to conventional heating and cooling systems owing to their higher energy utilization efficiency. GSHPs, also known as geothermal heat pumps, are a promising new technology that has been used for the last few years in the Korean market. A geothermal energy system has been developed over the last two years and a ground-heat-source water thermal-storage heat-pump cooling and heating system in Gu-mi city was built. Trial performance tests were conducted on the system. The actual proof examination was accomplished and the performance of the system was investigated. The coefficient of performance of the heat pump unit was 4.29 for cooling and 3.97 for heating. Thus, the presented system is expected to be used for energy savings and active alternative energy use.
The future cost to the United Kingdom's railway network of heat-related delays and buckles caused by the predicted increase in high summer temperatures owing to climate change
Authors: Dobney K , Baker C J , Chapman L , Quinn A D
Published: September 2009

Climate change predictions suggest a trend towards hotter drier summers in the UK. At extreme high temperatures the railway network is prone to dangerous, damaging, and expensive rail buckles. In order to reduce the risk of a rail buckle, emergency speed restrictions are introduced which can be costly. This article presents a quantification of the effects of higher summer temperatures due to climate change on the UK railway network. A combination of analogue techniques and a weather generator are used to establish trends between heat-related delays and temperatures. Costs are assigned to the change in frequency and severity of delays and evidence-based recommendations are made for future operations. The results demonstrate that the costs incurred as a result of the hot summer of 2003 will become typical in the 2050s (high emissions scenario) and 2080s (low emissions scenario). If no changes are made to maintenance regimes, it is estimated that the total costs of heat-related delays will eventually double to nearly £23 M during extreme summers.
Model reference control for human-operated robots and application to a robotic manipulator
Authors: Uchiyama N , Mori A
Published: September 2009

As fully automated robotic systems are difficult to realize from the viewpoint of cost efficiency and currently available technologies, human-robot cooperative systems have been widely studied. This paper presents a model reference control approach for a human-operated robotic system. This approach provides functions to incorporate commands given by a human operator and compensate for mistakes committed by the operator in real time, and is applied to a manipulator control whose objective is to transport an object on a table at the end-effector. The proposed method provides the following three functions: collision avoidance, tumble avoidance of the transported object, and singular point avoidance, even when the human operator makes mistakes during operation. There are many applications of this type of robotic manipulator in industrial and household tasks. The effectiveness of the proposed method is confirmed by the experiments in which several unskilled operators operate the manipulator to transport an object in a narrow space.
Mobile robot localization using robust extended H∞ filtering
Authors: Yang Fuwen , Wang Zidong , Lauria Stanislao , Liu Xiaohui
Published: September 2009

In this paper, a novel methodology is provided for accurate localization of a mobile robot using autonomous navigation based on internal and external sensors. A new robust extended H∞ filter is developed to deal with the non-linear kinematic model of the robot and the non-linear distance measurements, together with process and measurement noises. The proposed filter relies on a two-step prediction-correction structure, which is similar to a Kalman filter. Simulations are provided to demonstrate the effectiveness of the proposed method.
Sliding mode-based friction control with adaptive dual friction observer and intelligent uncertainty compensator
Authors: Han S I , Lee K S
Published: September 2009

A robust friction compensation scheme is studied using a dual-friction-parameter observer and a recurrent neural network combined with sliding mode control. To handle non-linear friction parameters, a dual-friction-model-based observer is used to estimate the friction parameter of the LuGre friction model. In addition, an approximating method for the system uncertainty is developed using a recurrent neural network approach to improve the precision positioning degree. Simulated and experimental results are presented that validate the performance of the proposed friction compensation scheme.
Observer-based H∞ control of networked non-linear systems for multiple sensors with different packet losses probabilities
Authors: Li J-G , Yuan J-Q
Published: September 2009

This paper investigates the observer-based H∞ control problem of networked non-linear systems with global Lipschitz non-linearities and for multiple sensors with different packet-loss rates. It is supposed that in the communication channels from the multiple sensors to the controller each sensor has an individual random data missing probability. The random packet loss is modelled as a Bernoulli distributed white sequence with a known conditional probability distribution. In the presence of random multiple packet losses, sufficient conditions for the existence of an observer-based feedback controller are derived, such that the closed-loop networked non-linear system is globally exponentially stable in the sense of mean square and a prescribed H∞ disturbance-rejection-attenuation performance is also achieved. A linear matrix inequality (LMI) approach for designing such observer-based H∞ controller is then presented. With the help of the LMI solvers, the observer-based H∞ controller can easily be obtained. Finally, a numerical example is used to demonstrate the effectiveness of the proposed method.
Effects of Fischer—Tropsch diesel fuel on soot formation processes in a diesel spray flame
Authors: Aizawa T , Kosaka H
Published: September 2009

In order to examine the mechanism by which diesel soot emission is reduced when using Fischer—Tropsch diesel (FTD) fuel compared with conventional diesel fuel (JIS#2) under exhaust gas recirculation conditions, the soot formation processes in a diesel spray flame of the two different fuels (FTD and JIS#2) under different ambient oxygen concentrations (21 to 10%) were investigated via excitation—emission matrix analysis of polycyclic aromatic hydrocarbons (PAHs) and high-speed laser shadowgraphy of soot particles. The experiments were conducted using an optically accessible constant-volume combustion vessel under a diesel-like condition ( Ta = 940 K and Pa = 2.5 MPa). In the FTD-fuelled diesel spray flame, the timing and region for the first appearance of PAH laser-induced fluorescence (LIF) and soot particles in the flame were delayed and shifted downstream compared with JIS#2. For JIS#2, the LIF appeared first in the shorter wavelength region (350 to 400 nm) and then shifted to the longer wavelength region (above 400 nm), while in the case of FTD, the LIF was observed not in the shorter wavelength but only in the longer wavelength region. The production of soot in the flame was increased by lowering the ambient oxygen concentration from 21 to 15% for both fuels, while the timing and region for the first appearance of soot and PAHs in the flame were delayed and shifted downstream. By lowering the oxygen concentration further down to 10%, the timing and region for the first appearance of PAHs and soot were further delayed and shifted downstream and the production of soot was decreased.
In-cylinder stratification of external exhaust gas recirculation for controlling diesel combustion
Authors: Fuyuto T , Nagata M , Hotta Y , Inagaki K , Nakakita K , Sakata I
Published: September 2009

A technique for achieving the in-cylinder stratification of external exhaust gas recirculation (EGR) gas in direct-injection (DI) diesel engines has been developed to reduce toxic exhaust emissions. The external EGR gas is supplied from one of the two intake ports which can create a swirl flow in either the upper or lower portion of the cylinder during the intake stroke. In the final stage of the compression stroke, a squish flow conveys the vertically stratified EGR gas into the piston cavity, generating a radially stratified EGR gas in the piston cavity at the end of the compression stroke. This strategy for achieving EGR gas stratification in the piston cavity was developed by using an unsteady computational fluid dynamics (CFD) code. Prior to the exhaust emission tests, the accuracy of the simulation was evaluated by planer laser-induced fluorescence (LIF) imaging. The exhaust emission tests showed that there was less smoke emission under medium load conditions when the EGR gas was delivered to the inner part of the piston cavity. The mechanism of this smoke reduction was investigated using CFD simulation, which is based on a series of calculations related to the internal flow of the injector nozzle, the in-cylinder fuel spray, and mixture formation and combustion. It has been shown that, at the beginning of the combustion, the higher concentration of EGR gas in the inner part of the cavity lowers the combustion temperature and reduces the soot formation rate. Air, which exists in the outer part of the cavity at the start of fuel injection, enhances the oxidation of the soot cloud in the piston cavity periphery in the latter half of the combustion period.
What medical specialists like and dislike about health technology assessment reports
Authors: Lehoux Pascale , Hivon Myriam , Denis Jean-Louis , Tailliez Stephanie
Published: September 2009

Objective:

To examine how medical specialists view health technology assessment (HTA) and its role in policy-making.

Methods:

Semi-structured interviews with 28 medical specialists practising in Quebec and Ontario (Canada) to examine their views on an HTA report relevant to their specialty (prostate-specific antigen screening, electroconvulsive therapy and prenatal screening for Down's syndrome).

Results:

Medical specialists represent a particularly demanding audience for HTA producers because they are knowledgeable about current studies in their field and often contribute to the evidence base that HTA seeks to synthesize. In all three cases, specialists not only challenged specific points in the content of the HTA reports but also offered different and sometimes conflicting appraisals of the clinical relevance and policy implications. More than just the timeliness and usefulness of HTA findings are at issue. The views of specialists are grounded in a clinical understanding of what counts as evidence and how decisions should be made, a view that contrasts with the societal perspective of HTA.

Conclusions:

HTA producers cannot afford to overlook medical specialists who play a key role in the adoption of health technologies. Establishing a transparent dialogue between producers and users of HTA reports could enrich policy recommendations.
Bringing genetics into primary care: Findings from a national evaluation of pilots in England
Authors: Martin Graham , Currie Graeme , Finn Rachael
Published: September 2009

Objectives:

Developments in genetic knowledge and clinical applications are seen as rendering traditional modes of organizing genetics provision increasingly inappropriate. In common with a number of developed world countries the UK has sought to increase the role of primary care in delivering such services. However, efforts to reconfigure service delivery face multiple challenges associated with divergent policy objectives, organizational boundaries and professional cultures. This paper presents findings from an evaluation of an English initiative to integrate genetics into ‘mainstream’ clinical provision in the National Health Service.

Methods:

Qualitative research in 11 case-study sites focusing on attempts by pilots funded by the initiative to embed knowledge and provision within primary care illustrating barriers faced and the ways in which these were surmounted.

Results:

Lack of intrinsic interest in clinical genetics among primary care staff was compounded by national targets that focused their attention elsewhere and by service structures that rendered genetics a peripheral concern demanding minimal engagement. Established divisions between the commissioning of mainstream and specialist services, along with the pressures of shorter-term targets, impeded ongoing funding.

Conclusions:

More wide-ranging policy and organizational support is required if the aim of entrenching genetics knowledge and practice across the Health Service is to be realized.
Images in Health Care: Potential and Problems
Authors: Williams Brian , Cameron Linda
Published: September 2009

Although communication issues within health care have received greater research and policy attention in recent years, one growing aspect of such communication has been largely overlooked. In this paper we suggest that visual forms of communication, at both the individual and population level, are increasingly used and relied upon. This seems appropriate given a general shift towards a more visual and visually literate society, and the potential of images to convey complex information and influence both beliefs and emotion. However, we also argue that the widespread use of such a potentially powerful tool necessitates a solid evidence base that is currently lacking. Such a lack leaves image-based interventions at best potentially ineffective and at worst harmful. We examine the reasons for the paucity of research in this area and suggest that in fact a multitude of supportive research and theory exists but that at present it is spread across a range of academic fields with little interdisciplinary dialogue. Given the current desire to see increased inter- and multidisciplinary dialogue and the acceptance of the need for theoretical and empirical underpinnings for complex interventions, it would seem that there may now be both the will and the way forward to forge new collaborations, integrate such theories and develop a more sophisticated evidence base to support the growing use of images in health care settings.
Evaluation of the impact of program budgeting and marginal analysis in Vancouver Island Health Authority
Authors: Dionne Francois , Mitton Craig , Smith Neale , Donaldson Cam
Published: September 2009

Objective:

The objective of this research was to provide further insights into the ability of Program Budgeting and Marginal Analysis (PBMA) to help health care decision-makers in deciding where to allocate scarce resources so as to best meet their organizational objectives.

Methods:

We report on a case study of PBMA implementation. The main source of information was two sets of semi-structured evaluation interviews conducted with senior decision-makers after each of the first two years of PBMA implementation in Vancouver Island Health Authority (VIHA), Canada. These interviews were analysed thematically, with initial coding based upon themes that had been identified in the previous stage of the research.

Results:

Many of the initial problems with PBMA implementation resolved themselves over time as participants became more familiar with the process. However, some problems needed to be addressed explicitly through changes in procedures. Establishing procedures for handling ‘must-dos’ (i.e. spending priorities, that are externally mandated) did not replace the need to define explicitly the extent of the organization's discretionary spending authority.

Conclusion:

Faced with claims that typically outstrip available resources, health care decision-makers need a process to guide allocation decisions. PBMA has demonstrated at VIHA an ability to handle some of the key issues associated with this challenge. Our analysis has produced lessons that should facilitate future implementation but has also shown that resource allocation criteria selection and the extent of executive discretion are likely to be ongoing challenges.
A Bayesian method for the synthesis of evidence from qualitative and quantitative reports: The example of antiretroviral medication adherence
Authors: Voils Corrine , Hassselblad Vic , Crandell Jamie , Chang Yunkyung , Lee Eunjeong , Sandelowski Margarete
Published: September 2009

Objectives:

Bayesian meta-analysis is a frequently cited but very little-used method for synthesizing qualitative and quantitative research findings. The only example published to date used qualitative data to generate an informative prior probability and quantitative data to generate the likelihood. We developed a method to incorporate both qualitative and quantitative evidence in the likelihood in a Bayesian synthesis of evidence about the relationship between regimen complexity and medication adherence.

Methods:

Data were from 11 qualitative and six quantitative studies. We updated two different non-informative prior distributions with qualitative and quantitative findings to find the posterior distribution for the probabilities that a more complex regimen was associated with lower adherence and that a less complex regimen was associated with greater adherence.

Results:

The posterior mode for the qualitative findings regarding more complex regimen and lesser adherence (using the uniform prior with Jeffreys’ prior yielding highly similar estimates) was 0.588 (95% credible set limits 0.519, 0.663) and for the quantitative findings was 0.224 (0.203, 0.245); due to non-overlapping credible sets, we did not combine them. The posterior mode for the qualitative findings regarding less complex regimen and greater adherence was 0.288 (0.214, 0.441) and for the quantitative findings was 0.272 (0.118, 0.437); the combined estimate was 0.299 (0.267, 0.334).

Conclusions:

The utility of Bayesian methods for synthesizing qualitative and quantitative research findings at the participant level may depend on the nature of the relationship being synthesized and on how well the findings are represented in the individual reports.
Evidence-based practice in British complementary and alternative medicine: Double standards?
Authors: Hunt Katherine , Ernst Edzard
Published: September 2009

Objectives:

The principles of evidence-based practice (EBP) are fundamental to medical ethics and seem essential for any form of health care. In 2000, a House of Lords Select Committee recommended that the ethos of EBP should extend to complementary and alternative medicine. The aim of this investigation was to determine whether EBP is incorporated in the codes of ethics of British complementary and alternative medicine organizations.

Methods:

We obtained the codes of the following bodies: Association of Naturopathic Practitioners, Association of Traditional Chinese Medicine (UK), Ayurvedic Practitioners Association, British Acupuncture Council, Complementary and Natural Healthcare Council, European Herbal Practitioners Association, General Chiropractic Council, General Osteopathic Council, General Regulatory Council for Complementary Therapies, National Institute of Medical Herbalists, Register of Chinese Herbal Medicine, Society of Homeopaths, UK Healers, Unified Register of Herbal Practitioners. We then extracted the statements referring to EBP and compared this with what the respective codes of British doctors and nurses proscribed.

Results:

Only the General Chiropractic Council, the General Osteopathic Council and the General Regulatory Council for Complementary Therapies oblige their members to adopt EBP.

Conclusions:

This discloses double standards in UK health care which may compromise patient safety.
How to review a paper
Authors: Wright Kath , Harden Melissa , Wright Kath , Misso Kate
Published: September 2009

Peer review is integral to assuring the quality of papers that are published in the scientific literature. Many health professionals at some point in their career will be invited by a journal editor to review a manuscript that has been submitted for publication. What resources are available on the web to support reviewers in this task? This edition of ‘What's on the web’ pulls together some of the essential websites that provide guidance, tips, background information and current debates about the process of peer review.

If you would like to alert readers to useful web pages or suggest topics for this column, please send details to:
Real-time fluorescence detection of exoribonucleases
Authors: Sinturel Flore , Pellegrini Olivier , Xiang Song , Tong Liang , Condon Ciarán , Bénard Lionel
Published: September 2009

The identification of RNases or RNase effectors is a continuous challenge, particularly given the current importance of RNAs in the control of genome expression. Here, we show that a fluorogenic RNA–DNA hybrid is a powerful tool for a real-time fluorescence detection and assay of exoribonucleases (RT-FeDEx). This RT-FeDEx assay provides a new strategy for the isolation, purification, and assay of known and unknown exoribonucleases.
Examining Demand Elasticities in Hanemann's Framework: A Theoretical and Empirical Analysis
Authors: Mehta Nitin , Chen Xinlei (Jack) , Narasimhan Om
Published: September 2009

This paper examines demand elasticities using an integrated framework proposed by Hanemann [Hanemann, M. W. 1984. Discrete/continuous models of consumer demand. Econometrica 52(3) 541–561], which models the incidence, brand choice, and quantity decisions of a consumer as an outcome of her utility maximization subject to budget constraints. Although the Hanemann framework has been the mainstay of earlier efforts to examine these decisions jointly, empirical researchers who have used the it to study purchase behavior have often found that the quantity elasticities are around −1, regardless of the brand or category. We attempt to uncover the underlying reasons for this finding and propose approaches to get as close to the “true” quantity elasticities as possible. We do this by (i) analytically demonstrating how assumptions on the distribution of the brand-specific econometrician's errors imply certain restrictions that in turn force quantity elasticities to −1, (ii) discussing how these restrictions can be alleviated by considering a suitable specification of unobserved parameter heterogeneity, and (iii) using scanner data to empirically illustrate the impact of the restrictions on quantity elasticities and the relative efficacy of multiple specifications of unobserved heterogeneity in easing those restrictions. We find that the specification of unobserved heterogeneity crucially influences estimates of quantity elasticities and that the mixture normal specification outperforms the alternatives.
An Audit of Dental General Anaesthetic Referral from a General Dental Practice in South Wales
Authors: Richards Wayne , Razzaq Kamran , Higgs Gary
Published: September 2009

Aims

The aim of this audit was to quantify the number of patients that received a dental general anaesthetic (DGA) between 1999 and 2007 following referral from a general dental practice. It also aimed to establish the deprivation status of those referred and to investigate further dental treatment pathways of these patients.

Methods

Data were collected from all patient records held by the practice. The information collected included: postcode, gender, age at the close of the study, age at time of DGA, reason for DGA, number of teeth extracted, and details of further ongoing care. In the absence of individual level socioeconomic data, a deprivation score (derived from the Welsh Index of Multiple Deprivation [WIMD]) was appended to each record in order to provide a measure of deprivation based on the postcode of the patient.

Results

Two hundred and eighty-seven patients were referred for DGA during the nine-year period. Their mean age was 9.4 years (95% confidence interval [CI] = 8.4, 10.4) and 30.7% were children aged five years or younger. The most common reason for DGA was dental caries. The mean number of teeth extracted was 4.5 (95% CI = 4.1, 4.9). Patients living in deprived areas were more likely to be referred for DGA. Of the 87 who did not subsequently attend for continuing care, 72 were from deprived areas compared with 15 from more affluent areas ( P=0.003).

Conclusions

In proportion to the number of patients registered at a practice, the number of referrals for DGAs was relatively low. Patients categorised as deprived (based on their residential postcode) received more referrals for DGAs than those from more affluent areas. Patients from deprived locations were significantly more likely not to attend for continuing care after their DGA than those from more affluent areas.
Mentoring. A Quality Assurance Tool for Dentists Part 5: The Roots of the Modern Approach to Mentoring and Coaching
Authors: Holt Vernon P , Ladwa Russ
Published: September 2009

Mentoring and coaching, as they are currently practised, are relatively new techniques for working with people. The roots of the current approach can be traced back to the psychotherapist Carl Rogers, who developed a new ‘person-centred approach’ to counselling and quickly realised that this approach was also appropriate for many types of relationship, from education to family life. Rogers’ thinking was deeply influenced by dialogues with his friend, the existentialist philosopher Martin Buber.

Developments in psychology building upon this new person-centred approach include transactional analysis (TA) and neurolingusitic programming (NLP). More recently, solutions-focused approaches have been used and a related approach to leadership in the business environment—strengths-based leadership—has been developed.

In recent years, developments in neuroscience have greatly increased understanding not only of how the brain is ‘wired up’ but also of how it is specifically wired to function as a social organ. The increased understanding in these areas can be considered in the context of emotional and social intelligence.

These concepts and knowledge have been drawn together into a more structured discipline with the development of the approach known as positive psychology, the focus of which is on the strengths and virtues that contribute to good performance and authentic happiness.
Cementoblastoma in the Maxilla: A Case Report
Authors: Barker Gillian L , Begley Anne , Balmer Colette
Published: September 2009

The cementoblastoma is a rare, benign odontogenic tumour. It is generally asymptomatic and usually occurs in young adults. It is more common in males. It is most often associated with mandibular molar teeth and has a characteristic radiographic appearance. This case report is of a young male patient who presented with a cementoblastoma associated with a maxillary second molar. The initial presentation was to his dentist with pain, which was assumed to be of dental origin. This case highlights the importance of adequate radiographic investigation and appropriate interpretation in forming a diagnosis. It also serves as a reminder that rare odontogenic tumours may present initially in primary care and it is essential that all practitioners are aware of them.
Improving Access to Oral Surgery Services in Primary Care
Authors: Kendall Nick
Published: September 2009

This paper describes the innovative use of National Health Service (NHS) dental commissioning powers to develop specialist primary care based oral surgery services. The outcomes, after one full year of the scheme, have been substantial improvement in access and reduced waiting times for patients, further development of NHS primary care dental services through commissioning processes, increased use and engagement of oral surgery specialists outside of a hospital setting, and considerable ongoing savings to the NHS. Collaborative working between hospital consultants and managers, Primary Care Trust dental commissioners, general dental practice providers, specialist oral surgeons and a dental public health consultant has resulted in sustainable benefits to patients and the NHS within the World Class Commissioning framework.