bluuebunny/crossref_metadata_2025_split huggingface dataset:
Issues in weaning from mechanical ventilation: literature review
Authors: Rose Louise , Nelson Sioban 
Published: March 2006

Aim.  The aim of this paper is to raise questions on the effect of skill mix and organizational structure on weaning from mechanical ventilation.Background.  Mechanical ventilation is an essential life‐saving technology. There are, however, numerous associated complications that influence the morbidity and mortality of patients receiving intensive care. Therefore, it was essential to use the safest and most effective form of ventilation for the shortest possible duration. Because of the potential complications and costs of mechanical ventilation, research to date have focused on accurate weaning readiness assessment, methods and organizational aspects that influence the weaning process.Method.  In early 2005, the literature was reviewed from 1986 to 2004 by accessing the following databases: Medline, Proquest, Science Direct, CINAHL, and Blackwell Science. The keywords mechanical ventilation, weaning, protocols, critical care, nursing role, decision‐making and weaning readiness were used separately and combinations.Discussion.  Controversy exists in weaning practices about appropriate and efficacious weaning readiness assessment indicators, the best method of weaning and the use of weaning protocols. Arguably, the implementation of weaning protocols may have little effect in an environment that favours collaboration between nursing and medical staff, autonomous nursing decision‐making in relation to weaning practices, and high numbers of nurses qualified at postgraduate level.Conclusion.  Further research is required that better quantifies critical care nurses’ role in weaning practices and the contextual issues that influence both the nursing role and the process of weaning from mechanical ventilation.
Feeding and dementia: a systematic literature review
Authors: Watson Roger , Green Sue M. 
Published: March 2006

Aim.  This paper reports a systematic review of the literature on interventions to promote oral nutritional intake of older people with dementia and feeding difficulty between 1993 and 2003.Background.  Older people with dementia commonly experience difficulty with feeding, especially in the later stages of the condition. This topic and related nursing care was reviewed in 1993 and the conclusion was that there was little research into interventions that nurses could use to alleviate feeding difficulty.Method.  A systematic review of the literature was carried out using the CINAHL, Medline, EMBASE and Cochrane databases and the search terms ‘feeding’, ‘eating’ and ‘dementia’ combined as follows: ‘(feeding or eating) and (dementia)’. A second search was carried out combining the search terms ‘mealtimes’ and ‘dementia’ as follows: ‘mealtimes and dementia’. The literature search was carried out on 1 December 2003 and papers were included in the review if retrieved by 31 December 2003. English language papers only were retrieved.Results.  Sixty‐seven papers were retrieved, of which 13 addressed interventions aimed at helping older people with dementia to feed. All studies reported positive outcomes but only one randomized controlled trial was reported. Music was the most common intervention but there were no standardized interventions or outcomes across the studies and none reported the use of power analysis to decide on sample size. There were problems in some studies with confounding variables.Conclusions.  Further research is needed into interventions aimed at how nurses can help older people with dementia to feed. There are some promising lines of enquiry, with music being one of these, but future studies need to use adequate samples and to use power calculations and account adequately for confounding variables. There is also a need to standardize interventions and outcomes across such studies to facilitate meta‐analysis.
Risk assessment scales for pressure ulcer prevention: a systematic review
Authors: Pancorbo‐Hidalgo Pedro L. , Garcia‐Fernandez Francisco Pedro , Lopez‐Medina Isabel Ma , Alvarez‐Nieto Carmen 
Published: March 2006

Aim.  This paper reports a systematic review conducted to determine the effectiveness of the use of risk assessment scales for pressure ulcer prevention in clinical practice, degree of validation of risk assessment scales, and effectiveness of risk assessment scales as indicators of risk of developing a pressure ulcer.Background.  Pressure ulcers are an important health problem. The best strategy to avoid them is prevention. There are several risk assessment scales for pressure ulcer prevention which complement nurses’ clinical judgement. However, some of these have not undergone proper validation.Method.  A systematic bibliographical review was conducted, based on a search of 14 databases in four languages using the keywords pressure ulcer or pressure sore or decubitus ulcer and risk assessment. Reports of clinical trials or prospective studies of validation were included in the review.Findings.  Thirty‐three studies were included in the review, three on clinical effectiveness and the rest on scale validation. There is no decrease in pressure ulcer incidence was found which might be attributed to use of an assessment scale. However, the use of scales increases the intensity and effectiveness of prevention interventions. The Braden Scale shows optimal validation and the best sensitivity/specificity balance (57·1%/67·5%, respectively); its score is a good pressure ulcer risk predictor (odds ratio = 4·08, CI 95% = 2·56–6·48). The Norton Scale has reasonable scores for sensitivity (46·8%), specificity (61·8%) and risk prediction (OR = 2·16, CI 95% = 1·03–4·54). The Waterlow Scale offers a high sensitivity score (82·4%), but low specificity (27·4%); with a good risk prediction score (OR = 2·05, CI 95% = 1·11–3·76). Nurses’ clinical judgement (only considered in three studies) gives moderate scores for sensitivity (50·6%) and specificity (60·1%), but is not a good pressure ulcer risk predictor (OR = 1·69, CI 95% = 0·76–3·75).Conclusion.  There is no evidence that the use of risk assessment scales decreases pressure ulcer incidence. The Braden Scale offers the best balance between sensitivity and specificity and the best risk estimate. Both the Braden and Norton Scales are more accurate than nurses’ clinical judgement in predicting pressure ulcer risk.
Differential working memory impairment in bipolar disorder and schizophrenia: effects of lifetime history of psychosis
Authors: Glahn David C , Bearden Carrie E , Cakir Sibel , Barrett Jennifer A , Najt Pablo , Serap Monkul E , Maples Natalie , Velligan Dawn I , Soares Jair C 
Published: March 2006

Background:  Although bipolar disorder and schizophrenia have long been viewed as distinct illnesses, there is growing evidence that these two complex diseases share some common genes, which may manifest as overlapping neuropsychological impairments. Although working memory dysfunction has been proposed to be central to the pathophysiology of schizophrenia, it has received less attention in studies of bipolar disorder.Method:  We applied measures of working memory to patients with schizophrenia (n = 15), patients with schizoaffective disorder (n = 15), patients with psychotic (n = 11) and non‐psychotic (n = 15) bipolar disorder, and demographically matched healthy subjects (n = 32), in order to determine the extent to which these groups show common or unique impairments.Results:  While patients with bipolar disorder (with and without psychotic features) and those with schizophrenia/schizoaffective disorder were impaired on backward digit span, only patients with a lifetime history of psychotic features, regardless of diagnosis, were impaired on spatial delayed response task.Conclusions:  Backward digit span performance is comparable in bipolar disorder and schizophrenia, and may be an appropriate endophenotypic marker that cuts across diagnostic categories. In contrast, spatial working memory performance clearly distinguishes non‐psychotic bipolar disorder patients from patients with functional psychosis.
Life‐Chart Methodology: a long past and a short history
Authors: Livianos‐Aldana Lorenzo , Rojo‐Moreno Luis 
Published: March 2006

Objectives:  Nowadays, the use of the Life‐Chart Methodology is common in bipolar disorder clinics. Our aim was to present a chart from the Archives of the University Heidelberg (Germany).Methods:  The clinical case records dating from Emil Kraepelin's direction of the Psychiatric Clinic at Heidelberg were systematically screened.Results:  Among the clinical records of patients suffering from manic depressive illness we located one record with a detailed charting of the clinical course.Conclusions:  The chart reviewed shows that the Life‐Chart Method was used more than a hundred years ago and for the same purpose, as an aid to clinicians.
Effects of lamotrigine and lithium on body weight during maintenance treatment of bipolar I disorder
Authors: Sachs Gary , Bowden Charles , Calabrese Joseph R , Ketter Terence , Thompson Thomas , White Robin , Bentley Beth 
Published: March 2006

Objective:  The effect of lamotrigine maintenance therapy on body weight was assessed retrospectively in analyses of data from two double‐blind, placebo‐ and lithium‐controlled, 18‐month studies in patients with bipolar I disorder (n = 227 for lamotrigine, 190 for placebo, 166 for lithium).Methods:  Endpoints included mean change in weight, the percentage of patients with ≥7% change (increase, decrease, fluctuation) in weight, and the percentage of patients with weight‐related adverse events during double‐blind treatment.Results:  Mean weight remained stable during maintenance therapy with lamotrigine. In a mixed‐model repeated‐measures analysis, mean changes in weight (kg) at week 52 were −1.2 with lamotrigine, +0.2 with placebo, and +2.2 with lithium [estimated difference (95% CI) lamotrigine minus placebo = −1.3 (−3.6, 0.9), p = 0.237; lithium minus placebo = +2.0 (−0.3, 4.4), p = 0.094; lithium minus lamotrigine = +3.4 (1.4, 5.4), p < 0.001]. Analyses were truncated at week 52 because of the high incidence of missing data at later time points. The percentages of patients with a ≥7% weight gain, during randomized treatment, were 10.9%, 7.6% and 11.8% for the lamotrigine, placebo, and lithium groups, respectively. The percentages of patients with a ≥7% weight loss, during randomized treatment, were 12.1%, 11.5%, and 5.1% for the lamotrigine, placebo, and lithium groups, respectively. The percentage of patients with a ≥7% weight loss did not significantly differ between lamotrigine and placebo but was significantly higher with lamotrigine than lithium. The incidences of ≥7% weight changes and of weight changes reported as adverse events were comparable between active treatments and placebo.Conclusion:  Lamotrigine was associated with stable body weight during 1 year of treatment and was comparable to placebo in mean weight change, incidence of clinically significant weight change, and incidence of weight changes reported as adverse events in patients with bipolar disorder. Lithium was associated with weight gain, but the magnitude of lithium‐associated weight gain was lower in the current analysis than in previous studies.
Prospective open‐label study of pharmacokinetics, efficacy and safety of a new 10% liquid intravenous immunoglobulin in patients with hypo‐ or agammaglobulinemia
Authors: Björkander J. , Nikoskelainen J. , Leibl H. , Lanbeck P. , Wallvik J. , Lumio J. T. , Braconier J. H. , Pavlova B. G. , Birthistle K. , Engl W. , Walter S. , Ehrlich H. J. 
Published: March 2006

Background and Objectives The aim of this study was to evaluate the pharmacokinetics, efficacy and safety of a newly developed 10% liquid immunoglobulin preparation in patients with primary immunodeficiency diseases. This new preparation for intravenous use includes three dedicated virus clearance steps in its manufacturing process to ensure a high margin of viral safety.Materials and Methods This was a prospective, open‐label, non‐controlled, multicentre study. Twenty‐two subjects with primary immunodeficiency were treated initially with three infusions of a licensed intravenous immunoglobulin to standardize the immunoglobulin G (IgG) replacement therapy of all subjects to the same intravenous product. A total of nine infusions of the new 10% liquid preparation were subsequently administered.Results The median terminal half‐life of total IgG following administration of the new preparation was 30·1 days. Median terminal half‐lives for IgG subclasses IgG1, IgG2, IgG3and IgG4were 28·3, 31·3, 20·9 and 24·2 days, respectively. The median total serum IgG steady‐state trough level was 8·51 g/l. No severe infection episodes started after initiation of treatment with the new preparation. The median rate of mild or moderate infection episodes was 0·48 per month. A total of 194 infusions with the new 10% liquid immunoglobulin preparation were administered. The mean dose per infusion was 0·41 g/kg body weight and the maximum infusion rates recorded were 8 ml/kg/h. Adverse experiences were mostly mild and unrelated to the study drugs. Only 4% of infusions with the new product were followed by one or more related adverse experiences.Conclusion The new 10% liquid immunoglobulin preparation was well tolerated and shown to have an excellent pharmacokinetic, efficacy and safety profile. The liquid formulation provides convenience to patients and healthcare professionals.
Pall leukotrap affinity prion‐reduction filter removes exogenous infectious prions and endogenous infectivity from red cell concentrates
Authors: Sowemimo‐Coker S. O. , Pesci S. , Andrade F. , Kim A. , Kascsak R. B. , Kascsak R. J. , Meeker C. , Carp R. 
Published: March 2006

Background and Objectives  Three recent probable cases of transmission of a variant of human Creutzfeldt–Jakob disease (vCJD) through blood transfusion suggest that the disease can be transmitted through transfusion of blood components from presymptomatic blood donors. In this study, we investigated the performance of a new filter for reducing the levels of infectious prions (PrPSc) from red cell concentrates (RCC).Materials and Methods  Endogenous Infectivity: A pool of 500 ml of whole blood was collected from 263K‐strain scrapie‐infected hamsters into an anticoagulant, processed into non‐leucoreduced RCC (NL‐RCC), and then passed through a prion‐reduction filter. Pre‐ and postfiltration samples were tested for PrPSc by Western blot and infectivity by inoculation of healthy hamsters. Results of the endogenous infectivity study after 200 days post‐inoculation are discussed. Exogenous (Spiking) Study: Scrapie‐infected hamster brain homogenates containing PrPSc were added to human RCC and then filtered. Levels of PrPSc were determined by Western blot assay. The effect of prior leucodepletion of ‘spiked’ RCC on PrPSc removal by the prion‐removal filter was also assessed.Results In the endogenous infectivity study, at 200‐day observation time, the prefiltered RCC transmitted disease to six of the 187 hamsters, whereas the filtered RCC did not transmit disease to any of 413 animals, P = 0·001. The prion filter also significantly reduced the concentration of leucocytes in the RCC by about 4 logs, P < 0·05. In the exogenous (spiking) study, the level of PrPres was significantly reduced in RCC P < 0·05. Prior leucodepletion of the RCC with a leucoreduction filter did not significantly reduce the concentration of exogenously spiked PrPSc, P > 0·05.Conclusion  The use of this new prion‐reduction filter should reduce the risk of vCJD transmission through transfusion of RCC, the most widely transfused blood component.
A crack tip field estimation technique for the high‐temperature cyclic loading of structures
Authors: HABIBULLAH M. S. , PONTER A. R. S. 
Published: March 2006

ABSTRACTThe purpose of this paper is to present a methodology for the assessment of the near‐crack tip fields in structures operating at elevated temperatures in the creep range and subjected to cyclic mechanical and thermal loads. The method involves generating simplified extreme solutions, which corresponds to very short (rapid cycle) and long (slow cycle) cycle times, bounding the behaviour for intermediate cycle times. In such situations, by examining the increments of strain over a cycle of loading at the crack tip, the solutions may be related to the HRR fields and, hence, related to an equivalent constant load. Here, these solutions are generated using a nonlinear programming method, the linear matching method (LMM), on two bounding constitutive relationships with identical uniaxial data, Norton's law and the Bailey–Orowan model. These solutions are generated for the classical cracked axisymmetric Bree problem, presented as a contour of an equivalent path‐independent integral in creep, C*, by using a sampling point within an identified best‐matched HRR field.
Classification of Illumination Methods for Mixed Reality
Authors: Jacobs Katrien , Loscos Céline 
Published: March 2006

Abstract A mixed reality (MR) represents an environment composed both by real and virtual objects. MR applications are used more and more, for instance in surgery, architecture, cultural heritage, entertainment, etc. For some of these applications it is important to merge the real and virtual elements using consistent illumination. This paper proposes a classification of illumination methods for MR applications that aim at generating a merged environment in which illumination and shadows are consistent. Three different illumination methods can be identified: common illumination, relighting and methods based on inverse illumination. In this paper a classification of the illumination methods for MR is given based on their input requirements: the amount of geometry and radiance known of the real environment. This led us to define four categories of methods that vary depending on the type of geometric model used for representing the real scene, and the sdifferent radiance information available for each point of the real scene. Various methods are described within their category. The classification points out that in general the quality of the illumination interactions increases with the amount of input information available. On the other hand, the accessibility of the method decreases since its pre‐processing time increases to gather the extra information. Recent developed techniques managed to compensate unknown data with clever techniques using an iterative algorithm, hardware illumination or recent progress in stereovision. Finally, a review of illumination techniques for MR is given with a discussion on important properties such as the possibility of interactivity or the amount of complexity in the simulated illumination.
Principles and Applications of Computer Graphics in Medicine
Authors: Vidal F.P. , Bello F. , Brodlie K.W. , John N.W. , Gould D. , Phillips R. , Avis N.J. 
Published: March 2006

AbstractThe medical domain provides excellent opportunities for the application of computer graphics, visualization and virtual environments, with the potential to help improve healthcare and bring benefits to patients. This survey paper provides a comprehensive overview of the state‐of‐the‐art in this exciting field. It has been written from the perspective of both computer scientists and practising clinicians and documents past and current successes together with the challenges that lie ahead. The article begins with a description of the software algorithms and techniques that allow visualization of and interaction with medical data. Example applications from research projects and commercially available products are listed, including educational tools; diagnostic aids; virtual endoscopy; planning aids; guidance aids; skills training; computer augmented reality and use of high performance computing. The final section of the paper summarizes the current issues and looks ahead to future developments.
Rendering Soft Shadows using Multilayered Shadow Fins
Authors: Cai Xiao‐Hua , Jia Yun‐Tao , Wang Xi , Hu Shi‐Min , Martin Ralph R. 
Published: March 2006

AbstractGenerating soft shadows in real time is difficult. Exact methods (such as ray tracing, and multiple light source simulation) are too slow, while approximate methods often overestimate the umbra regions. In this paper, we introduce a new algorithm based on the shadow map method to quickly and highly accurately render soft shadows produced by a light source. Our method builds inner and outer translucent fins on objects to represent the penumbra area inside and outside hard shadows, respectively. The fins are traced into multilayered light space maps to store illuminance adjustment to shadows. The viewing space illuminance buffer is then calculated using those maps. Finally, by blending illuminance and shading, a scene with highly accurate soft shadow effects is produced. Our method does not suffer from umbra overestimation. Physical relations between light, objects and shadows demonstrate the soundness of our approach.
Particle Oriented Collision Detection using Simplicial Coverings and Tetra‐Trees
Authors: Jiménez Juan José , Feito Francisco R. , Segura Rafael J. , Ogáyar Carlos J. 
Published: March 2006

AbstractCollision detection (CD) among complex objects in motion is an open question because of its algorithmic complexity. In this paper, we present a CD algorithm between a particle and a complex rigid solid. In order to represent solids, we use a simplicial covering scheme by means of 3‐simplices. With this representation system, complex polyhedra and closed triangle meshes can be represented and used in CD with a particle. A particle can be represented by a point, where the real dimensions of the particle are not important. This CD algorithm has been extended for a particle represented by a sphere which in turn represents an approximation to the particle dimensions. In order to efficiently classify the particles and the simplices of the polyhedra covering, we use a new hierarchical data structure named tetra‐tree that decomposes the space into tetra‐cones. These algorithms also use bounding volumes and temporal and geometric coherence, as well as incremental calculations in order to determine the collision in an efficient and exact way. Because of the use of sign operations with signed volumes and barycentric coordinates, we conclude that operations carried out using this method are more robust and efficient than those used in classic algorithms.
A Weighted Error Metric and Optimization Method for Antialiasing Patterns
Authors: Laine S. , Aila T. 
Published: March 2006

Abstract Displaying a synthetic image on a computer display requires determining the colors of individual pixels. To avoid aliasing, multiple samples of the image can be taken per pixel, after which the color of a pixel may be computed as a weighted sum of the samples. The positions and weights of the samples play a major role in the resulting image quality, especially in real‐time applications where usually only a handful of samples can be afforded per pixel. This paper presents a new error metric and an optimization method for antialiasing patterns used in image reconstruction. The metric is based on comparing the pattern against a given reference reconstruction filter in spatial domain, and it takes into account psychovisually measured angle‐specific acuities for sharp features.