bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental design and sample size determination for testing synergism in drug combination studies based on uniform measures
Authors: Tan Ming , Fang Hong‐Bin , Tian Guo‐Liang , Houghton Peter J. 
Published: June 2003

AbstractIn anticancer drug development, the combined use of two drugs is an important strategy to achieve greater therapeutic success. Often combination studies are performed in animal (mostly mice) models before clinical trials are conducted. These experiments on mice are costly, especially with combination studies. However, experimental designs and sample size derivations for the joint action of drugs are not currently available except for a few cases where strong model assumptions are made. For example, Abdelbasit and Plackett proposed an optimal design assuming that the dose–response relationship follows some specified linear models. Tallarida et al. derived a design by fixing the mixture ratio and used a t‐test to detect the simple similar action. The issue is that in reality we usually do not have enough information on the joint action of the two compounds before experiment and to understand their joint action is exactly our study goal. In this paper, we first propose a novel non‐parametric model that does not impose such strong assumptions on the joint action. We then propose an experimental design for the joint action using uniform measure in this non‐parametric model. This design is optimal in the sense that it reduces the variability in modelling synergy while allocating the doses to minimize the number of experimental units and to extract maximum information on the joint action of the compounds. Based on this design, we propose a robust F‐test to detect departures from the simple similar action of two compounds and a method to determine sample sizes that are economically feasible. We illustrate the method with a study of the joint action of two new anticancer agents: temozolomide and irinotecan. Copyright © 2003 John Wiley & Sons, Ltd.
Displacement control of isolated structures with semi‐active control devices
Authors: Loh Chin‐Hsiung , Wu L. Y. , Lin P. Y. 
Published: June 2003

AbstractThis study investigates the application of a semi‐active control method utilizing a magnetorheological (MR) damper to reduce the response of an isolated structure subjected to earthquake excitations. A series of performance tests were carried out on a 2 kN MR damper and the Bouc–Wen model was utilized to establish the numerical model of the MR device. A fuzzy logic control algorithm was then applied to establish the controller. Results of numerical simulation indicated that the established control algorithm is useful to reduce displacement and acceleration responses of base‐isolated structures. Copyright © 2003 John Wiley & Sons, Ltd.
Predictive controlled stiffness devices in MDOF structures
Authors: Ribakov Y. 
Published: June 2003

AbstractThis paper presents a study of a predictive control system used to improve the behavior of a multistorey structure under strong earthquakes. The structure and application of supplemental controlled stiffness devices (CSD) are discussed. Instantaneous optimal control is used to obtain the control forces at each time step during an earthquake according to the predicted values of the displacements and the velocities of each storey. A linear autoregressive model with exogenous input (ARX) is used to predict the displacements and the velocities of the frame in order to overcome the time delay problem in the control system. Control of the forces developed in the CSD is possible, owing to the mechanical structure of the device. This device can be efficiently used as a controller because the forces developed in it are independent of the structure's displacements or velocities. Its efficiency is demonstrated in a numerical simulation of a seven‐storey building. The simulation shows that the behavior of a structure with the proposed predictive control system is significantly improved compared with that of an uncontrolled structure subjected to the same earthquakes. In this example, the displacements and velocities in the structure were predicted according to an ‘occurring’ earthquake by the ARX model and were used to obtain the optimal control forces (predictive control). These forces yielded a response of the structure with CSD that was similar to the response obtained with control forces, which were calculated from a ‘known’ complete history of the earthquake displacement and velocity values (instantaneous optimal control). Copyright © 2003 John Wiley & Sons, Ltd.
The state‐of‐the‐art of damage detection by vibration monitoring: the SIMCES experience
Authors: Roeck Guido De 
Published: June 2003

AbstractA major contribution to the status of vibration monitoring has been delivered by the European Brite EuRam research project BE‐3157, System Identification to Monitor Civil Engineering Structures (SIMCES). This paper gives a brief description of the project, the tests performed on bridge Z24 and the results obtained from these tests. The need for further research is indicated. Copyright © 2003 John Wiley & Sons, Ltd.
Sensors and systems for structural health monitoring
Authors: Van der Auweraer Herman , Peeters Bart 
Published: June 2003

AbstractThis paper reviews the subject of structural damage detection from the point of view of instrumentation. The focus is on the measurement and interpretation of structural variables such as vibration, displacement and curvature. Some major approaches in the area of civil engineering and aeronautics are presented. Especially the corresponding sensor and data collection solutions are discussed as well as the key technologies for relating variations in the measured parameters to damage. Copyright © 2003 John Wiley & Sons, Ltd.
Large amplitude free vibrations of beams – an energy approach
Authors: Rao G.V. , Raju K.K. 
Published: June 2003

AbstractThe conservation of energy principle, which says that the total energy of a vibrating system, at any given instant of time is constant, is used to evaluate the large amplitude free vibration behaviour of beams with immovable ends. With an assumed space mode, which satisfies the geometric boundary conditions, the final governing equation is obtained. This equation is solved by a numerical integration scheme to obtain the ratio of frequencies of nonlinear to linear systems. Comparison of the present results with those of other researchers on this topic and a Galerkin approximation is also included.
Stochastic structural topology optimization: existence of solutions and sensitivity analyses
Authors: Evgrafov A. , Patriksson M. , Petersson J. 
Published: June 2003

AbstractWe consider structural topology optimization problems including unilateral constraints arising from, for example, non‐penetration conditions in contact mechanics or non‐compression conditions for elastic ropes. To construct more realistic models and to hedge off possible failures or an inefficient behaviour of optimal structures, we allow parameters (for example, loads) defining the problem to be stochastic. The resulting nonsmooth stochastic optimization problem is an instance of stochastic mathematical programs with equilibrium constraints (SMPEC), or stochastic bilevel programs. The existence as well as the continuity of optimal solutions with respect to the lower bounds on the design variables are established. The question of continuity of the optimal solutions with respect to small changes in the probability measure is analysed. For a subclass of the problems considered the answer is affirmative, thus establishing the robustness of optimal solutions.
Weighted Lp estimates of solutions to boundary value problems for second order elliptic systems in polyhedral domains
Authors: Maz'ya V.G. , Roßmann J. 
Published: June 2003

AbstractIn this paper we are concerned with boundary value problems for general second order elliptic equations and systems in a polyhedral domain. We consider solutions in weighted Lp Sobolev spaces. A special section is dedicated to weak solutions. We prove solvability theorems and regularity assertions for the solutions.
Approximation theory methods for solving elliptic eigenvalue problems
Authors: Still G. 
Published: June 2003

AbstractEigenvalue problems with elliptic operators L on a domain G ⊂ R2 are considered. By applying results from complex approximation theory we obtain results on the approximation properties of special classes of solutions of Lu = 0 on G . These solutions are used as trial functions in a method for solving the eigenvalue problem which is based on a‐posteriori error bounds. Singular trial functions are applied to smooth the problem at corner points of G . In special situations, this method can produce approximations of eigenvalues and eigenfunctions with extremely high accuracy by only using a low number of trial functions. Some illustrative numerical examples for the eigenvalue problem with the Laplacian are presented. We discuss two problems from plasma physics (‘relaxed plasma’, ‘MHD‐equation’).
Weighting of acoustic- and trawl-survey indices for the assessment of North Sea herring
Authors: Simmonds E.J 
Published: June 2003

Abstract
Acoustic surveys are used in 20 stock assessments within the ICES community, and almost all as relative indices of abundance, but little has been done to explore their performance in detail. The North Sea herring acoustic survey started in 1979 and by 1984 had become an internationally-coordinated survey conducted annually in July. Along with trawl- and larvae-survey indices, it has been used to tune a catch-at-age assessment model of North Sea herring. In this article, the precision of the survey is estimated, using data at ICES statistical-rectangle level from 1989 to 2001, and bootstrap-resampling methods modified by geostatistical estimates of the spatial autocorrelation. Similar techniques are applied to the larvae, Methot and trawl surveys that provide the other data on the distribution and abundance of North Sea herring. The comparison of survey performance is also examined using the bootstrap estimates of abundance to give 1000 simulated assessments of North Sea herring using the integrated catch-at-age (ICA) method. The results of these analyses are compared and the annual acoustic survey is shown to provide the most precise estimate of relative abundance for adult North Sea herring each year. The weighting of the various indices within the assessment is investigated. A weighting method is presented that provides a more precise method for estimating the stock. The more precise assessments are compared for retrospective pattern. An assessment is proposed which provides the most precise stock estimates with the best retrospective pattern. This assessment has been reviewed and accepted by the ICES Advisory Committee on Fisheries Management. The importance of the acoustic survey and its contribution to the assessment in relation to the other indices is discussed.
Depression in Women’s Magazines
Authors: Borman Jan 
Published: June 2003

BACKGROUND: Mass communication research suggests that the media influence both what a population thinks about and how it thinks about an event or situation by controlling what is covered and how topics are framed. One medium, popular women’s magazines, has published depression-related articles for decades. However, little is known about the content and frame of these articles. OBJECTIVE: The research sought to determine what women’s magazines published about depression between 1980 and 2000. DESIGN: Articles published on depression in the top eight circulating women’s magazines, between 1980 to 1985 and 1995 to 2000 were retrieved and analyzed using qualitative media analysis methodology. RESULTS: Between the two periods, the magazines increased the number of published articles on depression and increasingly framed it as a treatable but stigmatized illness. CONCLUSION: Women’s magazines, which regularly publish information on depression, have high circulation rates, resulting in millions of exposures to their messages. Psychiatric nurse-authors have an opportunity to influence these messages.
Emergency Nurses’ Responses to a Survey about Means Restriction: An Adolescent Suicide Prevention Strategy
Authors: Grossman Janet , Dontes Arnim , Kruesi Markus J.P. , Pennington James , Fendrich Michael 
Published: June 2003

BACKGROUND: Little is known about nurses’ knowledge and practice of an injury control strategy (means restriction) with parents of adolescents at risk for suicide who are cared for in the emergency department. OBJECTIVES: This study examined the experiences of emergency nurses (N = 527) with suicidal adolescents; their training, knowledge, practice, and attitudes toward means restriction; and unit practice related to the delivery of means restriction education to parents by emergency nurses. DESIGN: A survey was mailed to all members of the Illinois Chapter of the Emergency Nurses Association. RESULTS: Although the majority (80%, n = 407) of respondents had recent experience with suicidal adolescents, only 24% (n = 122) had ever received means restriction training, 28% (n = 136) provided means restriction education to parents, and 18% (n = 89) worked in units where means restriction is standard practice. CONCLUSIONS: The findings of this study are consistent with injury control literature. The authors recommend training emergency department staff in means restriction, adopting a means restriction protocol for adolescents at risk for suicide, and conducting outcome studies to determine the effectiveness of training and practice.
Catatonia and other psychiatric symptoms with vitamin B12 deficiency
Authors: Berry N. , Sagar R. , Tripathi B. M. 
Published: June 2003

Objective: To study unusual psychiatric manifestation of vitamin B12 deficiency and related issues.Method: A case study of 52‐year‐old female and review of relevant literature.Results: Complete remission of psychiatric symptoms without recurrence for the next 4 years with vitamin B12 as the only specific therapy instituted.Conclusion: Importance of B12 estimation and replacement in patients with varied psychiatric manifestations.
Cognitive remediation of working memory deficits: durability of training effects in severely impaired and less severely impaired schizophrenia
Authors: Bell M. , Bryson G. , Wexler B. E. 
Published: June 2003

Objective: To determine whether augmenting work therapy (WT) with neurocognitive enhancement therapy (NET) yields greater improvement in working memory performance than WT alone and whether there is an interaction with severity of impairment.Method: A total of 102 participants with schizophrenia or schizoaffective disorder were categorized as severely or less severely cognitively impaired and randomly assigned to receive NET + WT or WT alone. NET consisted of cognitive training exercises in attention, memory, executive function, and social information processing, and WT was a 6‐month work program.Results: Comparison on Digits Backwards from intake to follow‐up revealed significantly greater improvement for participants receiving NET + WT, but there was no interaction with severity group. Follow‐up 6 months after training showed that training effects endured.Conclusion: NET + WT improved working memory for most participants regardless of impairment severity. Intensity and duration of training may have contributed to duration of effects. Findings support continued exploration of cognitive remediation.
Alterations in theory of mind in patients with schizophrenia and non‐psychotic relatives
Authors: Janssen I. , Krabbendam L. , Jolles J. , Van Os Jim 
Published: June 2003

Objective: It has been proposed that alterations in theory of mind underlie specific symptoms of psychosis. The present study examined whether alterations in theory of mind reflect a trait that can be detected in non‐psychotic relatives of patients with schizophrenia.Method: Participants were 43 patients with schizophrenia or schizoaffective disorder, 41 first‐degree non‐psychotic relatives and 43 controls from the general population. Theory of mind was assessed using a hinting task and a false‐belief task.Results: There was a significant association between schizophrenia risk and failure on the hinting task (OR linear trend = 2.01, 95% CI: 1.22–3.31), with relatives having intermediate values between patients and controls. Adjustment for IQ and neuropsychological factors reduced the association by small amounts. The association between schizophrenia risk and failure on the false‐belief tasks was not significant.Conclusion: Changes in theory of mind are associated with schizophrenia liability. General cognitive ability and neuropsycholo‐ gical measures seem to mediate only part of this association.
Personality and self‐variables: important determinants of subjective quality of life in schizophrenia out‐patients
Authors: Eklund M. , Bäckström M. , Hansson L. 
Published: June 2003

Objective: To investigate factors determining severely mentally ill patients’ self‐rated quality of life. The study hypothesized that objective life circumstances, personality, self‐variables, and psychopathology would be determinants of quality of life.Method: A total of 117 individuals with schizophrenia and related disorders were investigated. Structural equation modelling was used to: 1) investigate if one or more subfactors best described the covariance within each potential determinant and quality of life, 2) explore the relations between all variables and factors extracted in step 1.Results: A multi‐factorial model indicated that a self‐factor and two psychopathology factors worked as mediators of self‐rated quality of life, in turn composed of an internal and an external aspect. Personality dimensions and objective life circumstances accounted directly or indirectly for substantial parts of quality of life.Conclusion: The relative importance of individual characteristics and objective indices was shown. Trait‐like properties, such as the self‐factor and personality, explained most of the variation in self‐rated quality of life.
Anomalies of subjective experience in schizophrenia and psychotic bipolar illness
Authors: Parnas J. , Handest P. , Sæbye D. , Jansson L. 
Published: June 2003

Objective: Contemporary psychopathology, as a result of behaviourally dominated epistemological stance, downplays anomalies of the patient's subjectivity. This neglect has probably deleterious consequences for research in the causes and the boundaries of the schizophrenia spectrum conditions. The purpose of this study is to explore frequency of qualitative, not‐yet‐psychotic, anomalies of subjective experience in patients with residual schizophrenia and psychotic bipolar illness in remission.Method: The patients were examined with the Danish version of the Bonn Scale for the Assessment of Basic Symptoms (BSABS). Anomalies of experience were condensed into rational scales with good internal consistencies.Results: Diagnosis of schizophrenia was associated with elevated scores on the scales measuring perplexity (loss of immediate meaning), disorders of perception, disorders of self‐awareness, and marginally so, disorders of cognition.Conclusion: These findings, in conjunction with those from other, methodologically similar studies, suggest that certain anomalies of subjective experience aggregate significantly in schizophrenia. These experiential anomalies appear to be relevant for early differential diagnosis and therefore potentially useful in the preonset detection of the schizophrenia spectrum illness.
A 20‐year follow‐up study on schizophrenia in Singapore
Authors: Kua J. , Wong K. E. , Kua E. H. , Tsoi W. F. 
Published: June 2003

Objective: To assess the outcome and predictors of patients with schizophrenia 20 years later.Method: The patients, aged 15–39 years, with diagnosis of schizophrenia and first admitted to a national mental hospital in Singapore in 1975 were included. In 1980, 1985, 1990 and 1995, their hospital records were examined and the patients were interviewed to determine their working and treatment status. Possible predictors of good outcome and suicide data were determined.Results: A total of 402 patients were included. Over 20 years, there was lower percentage of patients working full time and proportionately more patients were receiving out‐patient treatment. Overall, about two‐third of the patients had a good/fair outcome. Shorter illness duration before admission was significantly associated with a good outcome. The suicide rate was the highest in the first 10 years.Conclusion: Most patients with schizophrenia had a good/fair outcome at 20 years.
Neurological soft signs in never‐treated schizophrenia
Authors: Venkatasubramanian G. , Latha V. , Gangadhar B. N. , Janakiramaiah N. , Subbakrishna D. K. , Jayakumar P. N. , Keshavan M. S. 
Published: June 2003

Objective:Studies of Neurological Soft Signs (NSS) in schizophrenia are confounded by handedness, inconsistent methodology, and prior treatment with neuroleptics. The study objective is to examine NSS in never‐treated schizophrenia.Method:We examined the NSS in treatment‐naïve schizophrenia patients (n = 21) and age, sex, education, and handedness matched normal controls (n = 21) using the modified Neurological Evaluation Scale with good inter‐rater reliability.Results:Schizophrenia patients had significantly more NSS than normals. No significant correlation was found between illness duration and NSS.Conclusion:Higher neurological signs in never‐treated patients and their lack of association with illness duration suggest neurodevelopmental etiopathogenesis of schizophrenia.
Association between minor physical anomalies and lateral ventricular enlargement in childhood and adolescent onset schizophrenia
Authors: Hata K. , Iida J. , Iwasaka H. , Negoro H. , Kishimoto T. 
Published: June 2003

Objective: The primary purpose of this study was to investigate the association between morphological abnormalities of brain and minor physical anomalies (MPAs) in childhood and adolescent onset schizophrenia.Method: Twenty‐seven patients who had been diagnosed with schizophrenia according to DSM‐IV criteria before 18 years of age were included in the study. MPAs were evaluated with the modified version of Waldrop scale (WS) by Green et al. Morphological abnormalities of brain was evaluated with ventricular‐brain ratio (VBR) by using cerebral magnetic resonance imaging (MRI) examination.Results: A significant positive correlation was observed between WS scores and VBRs.Conclusion: This result indicates a relationship between MPAs and lateral ventricular enlargement, and supports neurodevelopmental etiology in childhood or adolescent onset schizophrenia.
The neurology of learning and behavioural problems in pre‐adolescent children
Authors: Batstra L. , Neeleman J. , Hadders‐Algra M. 
Published: June 2003

Objective: The aim of the study was to evaluate whether in pre‐adolescent children specific types of minor neurological dysfunction (MND) are related to specific types of learning and behavioural problems, and whether it is the type or the severity of neurological dysfunction that matters most.Method: A total of 1186, 5.5–11‐year‐old, children were examined for the presence of clusters of signs of MND. Parents and teachers completed brief behaviour rating scales. In school‐aged children (n = 580) cognitive achievement was assessed using standardized Dutch tests. Least‐squares regression was used to examine neurobehavioural and neurocognitive links.Results: Children with more MND clusters performed worse scholastically and had more signs of attention deficit than others. Externalizing and internalizing behaviour were only linked to specific forms of MND.Conclusion: Evaluation of the neurological condition of the child with learning and behavioural problems offers insight into the aetiology and pathogenesis of these problems.