Optimal Way (optimal + way)

Distribution by Scientific Domains


Selected Abstracts


Report from the 1st Japanese Urological Association-Japanese Society of Medical Oncology joint conference, 2006: ,A step towards better collaboration between urologists and medical oncologists'

INTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2007
Hideyuki Akaza
Abstract: The 1st Japanese Urological Association,Japanese Society of Medical Oncology Joint Conference, titled ,A step towards better collaboration between urologists and medical oncologists', was held to coincide with the 44th Meeting of the Japan Society of Clinical Oncology, Tokyo, in October 2006. The main theme of the conference addressed the need for a subspecialty of medical oncologist within urology to keep abreast of advances in medical oncology. Urologists should become more involved in the postoperative management of urologic cancer. Consensus on the optimal way to move forward in the treatment of urological cancer is needed. The conference featured eight lectures surveying the present status of uro-oncology in Europe, the USA, Korea, Singapore, and Japan; the relationship between surgical oncologists and medical oncologists; global trends and international clinical trials in uro-oncology; and the future of urologic oncology. These were followed by a general discussion titled ,Achieving better collaboration between the surgical oncologist and the medical oncologist.' This report presents a roundup of the 1st Japanese Urological Association,Japanese Society of Medical Oncology Joint Conference. [source]


Nonlinear optimization of autonomous undersea vehicle sampling strategies for oceanographic data-assimilation

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 6 2007
Kevin D. Heaney
The problem of how to optimally deploy a suite of sensors to estimate the oceanographic environment is addressed. An optimal way to estimate (nowcast) and predict (forecast) the ocean environment is to assimilate measurements from dynamic and uncertain regions into a dynamical ocean model. In order to determine the sensor deployment strategy that optimally samples the regions of uncertainty, a Genetic Algorithm (GA) approach is presented. The scalar cost function is defined as a weighted combination of a sensor suite's sampling of the ocean variability, ocean dynamics, transmission loss sensitivity, modeled temperature uncertainty (and others). The benefit of the GA approach is that the user can determine "optimal" via a weighting of constituent cost functions, which can include ocean dynamics, acoustics, cost, time, etc. A numerical example with three gliders, two powered AUVs, and three moorings is presented to illustrate the optimization approach in the complex shelfbreak region south of New England. © 2007 Wiley Periodicals, Inc. [source]


Individualized population pharmacokinetic model with limited sampling for cyclosporine monitoring after liver transplantation in clinical practice

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2007
P. LANGERS
Summary Background, We recently developed and validated limited sampling models (LSMs) for cyclosporine monitoring after orthotopic liver transplantation based on individualized population pharmacokinetic models with Bayesian modelling. Aim, To evaluate LSM in practice, and to seek optimal balance between benefit and discomfort. Methods, In 30 stable patients, more than 6 months after orthotopic liver transplantation, previously switched from trough- to 2 h post-dose (C2)-monitoring, we switched to 3-monthly LSM 0,1,2,3 h-monitoring. During 18 months we evaluated dose, creatinine clearance, calculated area under the curve, intra-patient pharmacokinetic variability and ability to assess systemic exposure by several previously validated LSMs. Results, Within patients, there was variability of cyclosporine-area under the curve with the same dose (CV of 15%). Compared to C2-monitoring, there was no significant difference in dose (P = 0.237), creatinine clearance (P = 0.071) and number of rejections. Some models showed excellent correlation and precision with LSM 0,1,2,3 h comparing area under the curves (0,2 h: r2 = 0.88; 0,1,3 h: r2 = 0.91; 0,2,3 h: r2 = 0.92, all P < 0.001) with no difference in advised dose. Conclusions, The limited sampling model, with only trough- and 2-h sampling, yields excellent accuracy and assesses systemic exposure much better than C2 with less bias and greater precision. Considering the calculated intra-patient variability, more precision is redundant, so LSM 0,2 h seems the optimal way of cyclosporine-monitoring. [source]


Controller design for optimal tracking response in discrete-time systems

OPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 5 2007
O. A. Sebakhy
Abstract The problem of designing a controller, which results in a closed-loop system response with optimal time-domain characteristics, is considered. In the approach presented in this paper, the controller order is fixed (higher than pole-placement order) and we seek a controller that results in closed-loop poles at certain desired and pre-specified locations; while at the same time the output tracks the reference input in an optimal way. The optimality is measured by requiring certain norms on the error sequence,between the reference and output signals,to be minimum. Several norms are used. First, l2 -norm is used and the optimal solution is computed in one step of calculations. Second, l, -norm (i.e. minimal overshot) is considered and the solution is obtained by solving a constrained affine minimax optimization problem. Third, the l1 -norm (which corresponds to the integral absolute error-(IAE)-criterion) is used and linear programming techniques are utilized to solve the problem. The important case of finite settling time (i.e. deadbeat response) is studied as a special case. Examples that illustrate the different design algorithms and demonstrate their feasibility are presented. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Making the biodiversity monitoring system sustainable: Design issues for large-scale monitoring systems

AUSTRAL ECOLOGY, Issue 1 2004
IAN WATSON
Abstract There is strong demand for information about the status of, and trends in, Australia's biodiversity. Almost inevitably, this demand for information has led to demand for a broad-scale monitoring system. However, the decision to embark on a monitoring system should only be made once it has been established that a monitoring system is the optimal way to inform management. We stress the need to invest resources in assessing whether a monitoring system is necessary before committing resources to the design and implementation of the system. Current debate associated with the design of a biodiversity monitoring system has similarities to the debate within the range management profession in the early 1970s. The experience with range monitoring shows that large-scale monitoring systems such as those being proposed will require considerable resources, recurrently expended into the distant future, but with only a limited ability to adapt to new demands. Those involved in any biodiversity monitoring system will need to understand the implications of investing in a long-term monitoring programme. Monitoring sustainability will only be possible if the monitoring system is itself sustainable. We discuss a number of issues that need to be addressed before the system is at all sustainable. These attributes are a mix of biophysical, social and institutional attributes and highlight the view that monitoring systems of the type being suggested comprise an unusual mixture of attributes not found in typical scientific activity. The present paper is not a technical manual, but rather considers some of the design issues associated with designing and implementing large-scale monitoring systems. [source]


Synergy and sustainability in rural procedural medicine: Views from the coalface

AUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 1 2010
Andrew Swayne
Abstract Objective:,The practice of rural and remote medicine in Australia entails many challenges, including a broad casemix and the remoteness of specialist support. Many rural practitioners employ advanced procedural skills in anaesthetics, surgery, obstetrics and emergency medicine, but the use of these skills has been declining over the last 20 years. This study explored the perceptions of rural general practitioners (GPs) on the current and future situation of procedural medicine. Design:,The qualitative results of data from a mixed-method design are reported. Free-response survey comments and semistructured interview transcripts were analysed by a framework analysis for major themes. Setting:,General practices in rural and remote Queensland. Participants:,Rural GPs in Rural and Remote Metropolitan Classification 4,7 areas of Queensland. Main outcome measure:,The perceptions of rural GPs on the current and future situation of rural procedural medicine. Results:,Major concerns from the survey focused on closure of facilities and downgrading of services, cost and time to keep up skills, increasing litigation issues and changing attitudes of the public. Interviews designed to draw out solutions to help rectify the perceived circumstances highlighted two major themes: ,synergy' between the support from medical teams and community in ensuring ,sustainability' of services. Conclusions:,This article presents a model of rural procedural practice where synergy between staff, resources and support networks represents the optimal way to deliver a non-metropolitan procedural service. The findings serve to remind educators and policy-makers that future planning for sustainability of rural procedural services must be broad-based and comprehensive. [source]


Prediction of metabolic function from limited data: Lumped hybrid cybernetic modeling (L-HCM)

BIOTECHNOLOGY & BIOENGINEERING, Issue 2 2010
Hyun-Seob Song
Abstract Motivated by the need for a quick quantitative assessment of metabolic function without extensive data, we present an adaptation of the cybernetic framework, denoted as the lumped hybrid cybernetic model (L-HCM), which combines the attributes of the classical lumped cybernetic model (LCM) and the recently developed HCM. The basic tenet of L-HCM and HCM is the same, that is, they both view the uptake flux as being split among diverse pathways in an optimal way as a result of cellular regulation such that some chosen metabolic objective is realized. The L-HCM, however, portrays this flux distribution to occur in a hierarchical way, that is, first among lumped pathways, and next among individual elementary modes (EM) in each lumped pathway. Both splits are described by the cybernetic control laws using operational and structural return-on-investments, respectively. That is, the distribution of uptake flux at the first split is dynamically regulated according to environmental conditions, while the subsequent split is based purely on the stoichiometry of EMs. The resulting model is conveniently represented in terms of lumped pathways which are fully identified with respect to yield coefficients of all products unlike classical LCMs based on instinctive lumping. These characteristics enable the model to account for the complete set of EMs for arbitrarily large metabolic networks despite containing only a small number of parameters which can be identified using minimal data. However, the inherent conflict of questing for quantification of larger networks with smaller number of parameters cannot be resolved without a mechanism for parameter tuning of an empirical nature. In this work, this is accomplished by manipulating the relative importance of EMs by tuning the cybernetic control of mode-averaged enzyme activity with an empirical parameter. In a case study involving aerobic batch growth of Saccharomyces cerevisiae, L-HCM is compared with LCM. The former provides a much more satisfactory prediction than the latter when parameters are identified from a few primary metabolites. On the other hand, the classical model is more accurate than L-HCM when sufficient datasets are involved in parameter identification. In applying the two models to a chemostat scenario, L-HCM shows a reasonable prediction on metabolic shift from respiration to fermentation due to the Crabtree effect, which LCM predicts unsatisfactorily. While L-HCM appears amenable to expeditious estimates of metabolic function with minimal data, the more detailed dynamic models [such as HCM or those of Young et al. (Young et al., Biotechnol Bioeng, 2008; 100: 542,559)] are best suited for accurate treatment of metabolism when the potential of modern omic technology is fully realized. However, in view of the monumental effort surrounding the development of detailed models from extensive omic measurements, the preliminary insight into the behavior of a genotype and metabolic engineering directives that can come from L-HCM is indeed valuable. Biotechnol. Bioeng. 2010;106: 271,284. © 2010 Wiley Periodicals, Inc. [source]


Type 2 diabetes in families and diabetes prevention

EUROPEAN DIABETES NURSING, Issue 2 2008
FRCP Professor of Diabetic Molecular Medicine, M Walker MD
Abstract Type 2 diabetes frequently clusters in families. Non-diabetic first-degree relatives (offspring and siblings) of patients with type 2 diabetes have a three-fold increased lifetime risk of developing diabetes compared with the background population. This increased diabetes risk results from the combined effects of shared genetic and lifestyle factors. Extensive studies of non-diabetic relatives of type 2 diabetic families show that impaired insulin secretion, insulin resistance and an adverse cardiovascular risk factor profile exist well before the development of frank diabetes. Despite this well-documented adverse metabolic predisposition, patients with type 2 diabetes and their non-diabetic relatives generally have a limited understanding of the risks. Several large-scale studies, such as the Finnish Diabetes Prevention and Diabetes Prevention Program studies, indicate unequivocally that lifestyle modification through dietary change and exercise can dramatically decrease risk of progression to diabetes in high-risk subjects. However, such individuals pursue lifestyle changes only if they understand their own risk of developing diabetes. Further work is therefore needed to investigate and develop optimal ways of improving knowledge of diabetes risk in families of patients with type 2 diabetes, so that they can appreciate the potential benefits of diabetes prevention strategies. Copyright © 2008 FEND [source]


Coping strategies and health-related quality of life among spouses of continuous ambulatory peritoneal dialysis, haemodialysis, and transplant patients

JOURNAL OF ADVANCED NURSING, Issue 6 2000
Ragny Lindqvist RN PhD
Coping strategies and health-related quality of life among spouses of continuous ambulatory peritoneal dialysis, haemodialysis and transplant patients In the study reported here 55 spouses of patients living with end-stage renal disease (ESRD) were investigated with respect to coping strategies and health-related quality of life. Findings from the study were compared to two random samples of the Swedish general population (n = 454, and n = 1200). The study design was correlational and comparative. Coping was measured by the Jalowiec Coping Scale, and quality of life (QoL) by the Swedish Health-Related Quality of Life Survey (SWED-QUAL). Data were analysed using a number of statistical tests including Pearson's product moment correlations, Student's t -test and two way ANOVAs. The combined sample of spouses used significantly more optimistic and palliative coping than the general population, but less confrontative, self-reliant, evasive and emotive coping. In the study fatalistic, evasive and emotive coping was associated with low perceived efficiency in handling various aspects of the partners' situation. The male spouses used significantly less optimistic, supportive and palliative coping than did the female spouses. The spouses of transplant patients had better overall quality of life than the continuous ambulatory peritoneal dialysis and haemodialysis spouse groups, most likely due to the lower age of the former group. The study findings suggest that emotive, evasive and fatalistic coping are less than optimal ways to deal with problems occasioned by the partner's treatment. [source]