647 research outputs found
Joint Route Planning under Varying Market Conditions
Purpose - To provide empirical evidence on the level of savings that can be attained by joint route planning and how these savings depend on specific market characteristics.Design/methodology/approach - Joint route planning is a measure that companies can take to decrease the costs of their distribution activities. Essentially, this can either be achieved through horizontal cooperation or through outsourcing distribution to a Logistics Service Provider.The synergy value is defined as the difference between distribution costs in the original situation where all entities perform their orders individually, and the costs of a system where all orders are collected and route schemes are set up simultaneously to exploit economies of scale.This paper provides estimates of synergy values, both in a constructed benchmark case and in a number of real-world cases.Findings - It turns out that synergy values of 30% are achievable.Furthermore, intuition is developed on how the synergy values depend on characteristics of the distribution problem under consideration.Practical implications - The developed intuition on the nature of synergy values can help practitioners to find suitable combinations of distribution systems, since synergy values can quickly be assessed based on the characteristics of the distribution problem, without solving large and difficult Vehicle Routing Problems.Originality/value - this paper addresses a major impediment to horizontal cooperation: estimating operational savings upfront.Horizontal cooperation;Distribution;Outsourcing;Vehicle routing with time windows;Retail
Loss of heterozygosity for defined regions on chromosomes 3, 11 and 17 in carcinomas of the uterine cervix.
Loss of heterozygosity (LOH) frequently occurs in squamous cell carcinomas of the uterine cervix and indicates the probable sites of tumour-suppressor genes that play a role in the development of this tumour. To define the localization of these tumour-suppressor genes, we studied loss of heterozygosity in 64 invasive cervical carcinomas (stage IB and IIA) using the polymerase chain reaction with 24 primers for polymorphic repeats of known chromosomal localization. Chromosomes 3, 11, 13, 16 and 17, in particular, were studied. LOH was frequently found on chromosome 11, in particular at 11q22 (46%) and 11q23.3 (43%). LOH on chromosome 11p was not frequent. On chromosome 17p13.3, a marker (D17S513) distal to p53 showed 38% LOH, whereas p53 itself showed only 20% LOH. On the short arm of chromosome 3, LOH was frequently found (41%) at 3p21.1. The beta-catenin gene is located in this chromosomal region. Therefore, expression of beta-catenin protein was studied in 39 cases using immunohistochemistry. Staining of beta-catenin at the plasma membrane of tumour cells was present in 38 cases and completely absent in only one case. The tumour-suppressor gene on chromosome 3p21.1 may be beta-catenin in this one case, but (an)other tumour-suppressor gene(s) must also be present in this region. For the other chromosomes studied, 13q (BRCA-2) and 16q (E-cadherin), only sporadic losses (< 15% of cases) were found. Expression of E-cadherin was found in all of 37 cases but in six cases the staining was very weak. No correlation was found between clinical and histological parameters and losses on chromosome 3p, 11q and 17p. In addition to LOH, microsatellite instability was found in one tumour for almost all loci and in eight tumours for one to three loci. In conclusion, we have identified three loci with frequent LOH, which may harbour new tumour-suppressor genes, and found microsatellite instability in 14% of cervical carcinomas
Implementation of a shared care guideline for back pain: effect on unnecessary referrals
Objective: To determine the effect of the implementation of a shared care guideline for the lumbosacral radicular syndrome (LRS) on unnecessary early referrals and the duration of the total diagnostic procedure. Design: Introduction of shared care guideline in November 2005. Pre-test in 2005 (April to October), a first post-test in 2006 (April to October) and a second post-test in 2007 (April to October). Setting and Intervention: The introduction of a shared care guideline derived from national guidelines for GPs and several medical/paramedical specialists in two Dutch regions. Three hundred and sixty GPs, 550 physiotherapists and two hospitals (9 neurologists and 18 radiologists) were involved. The essential component of the guideline was a trade-off: if the GP complied with the conservative management approach in the first 6 weeks, the hospital guaranteed a priority appointment with the neurologist after 6 weeks, if still required. Main Outcome Measures: The neurologists in both hospitals registered whether a patient had been unnecessarily referred during the first 6 weeks. The duration of the total diagnostic procedure was defined as the number of days between referral by the GP and the consultation when the neurologist made the final diagnosis. Results: The percentage of patients being unnecessarily referred within 6 weeks fell significantly from 15% in 2005 to 9% in 2006 and 8% in 2007. The duration of the total diagnostic procedure also fell significantly in both the long and short terms. Conclusions: The introduction of a shared care guideline for all care providers in a region reduces the number of unnecessary early referrals for patients with LRS. © The Author 2010. Published by Oxford University Press in association with the International Society for Quality in Health Care
Modeling hospital infrastructure by optimizing quality, accessibility and efficiency via a mixed integer programming model
BACKGROUND: The majority of curative health care is organized in hospitals. As in most other countries, the current 94 hospital locations in the Netherlands offer almost all treatments, ranging from rather basic to very complex care. Recent studies show that concentration of care can lead to substantial quality improvements for complex conditions and that dispersion of care for chronic conditions may increase quality of care. In previous studies on allocation of hospital infrastructure, the allocation is usually only based on accessibility and/or efficiency of hospital care. In this paper, we explore the possibilities to include a quality function in the objective function, to give global directions to how the âoptimalâ hospital infrastructure would be in the Dutch context. METHODS: To create optimal societal value we have used a mathematical mixed integer programming (MIP) model that balances quality, efficiency and accessibility of care for 30 ICD-9 diagnosis groups. Typical aspects that are taken into account are the volume-outcome relationship, the maximum accepted travel times for diagnosis groups that may need emergency treatment and the minimum use of facilities. RESULTS: The optimal number of hospital locations per diagnosis group varies from 12-14 locations for diagnosis groups which have a strong volume-outcome relationship, such as neoplasms, to 150 locations for chronic diagnosis groups such as diabetes and chronic obstructive pulmonary disease (COPD). CONCLUSIONS: In conclusion, our study shows a new approach for allocating hospital infrastructure over a country or certain region that includes quality of care in relation to volume per provider that can be used in various countries or regions. In addition, our model shows that within the Dutch context chronic care may be too concentrated and complex and/or acute care may be too dispersed. Our approach can relatively easily be adopted towards other countries or regions and is very suitable to perform a âwhat-ifâ analysis
Factory Gate Pricing: An Analysis of the Dutch Retail Distribution
Factory Gate Pricing (FGP) is a relatively new phenomenon in retail distribution. Under FGP, products are no longer delivered at the retailer distribution center, but collected by the retailer at the factory gates of the suppliers. Owing to both the asymmetry in the distribution networks (the supplier sites greatly outnumber the retailer distribution centers) and the better inventory and transport coordination mechanisms, this is likely to result in high savings. A mathematical model was used to analyze the benefits of FGP for a case study in the Dutch retail sector. Extensive numerical results are presented to show the effect of the orchestration shift from supplier to retailer, the improved coordination mechanisms, and sector-wide cooperation
Successful implementation of new technologies in nursing care: a questionnaire survey of nurse-users
<p>Abstract</p> <p>Background</p> <p>A growing number of new technologies are becoming available within nursing care that can improve the quality of care, reduce costs, or enhance working conditions. However, such effects can only be achieved if technologies are used as intended. The aim of this study is to gain a better understanding of determinants influencing the success of the introduction of new technologies as perceived by nursing staff.</p> <p>Methods</p> <p>The study population is a nationally representative research sample of nursing staff (further referred to as the Nursing Staff Panel), of whom 685 (67%) completed a survey questionnaire about their experiences with recently introduced technologies. Participants were working in Dutch hospitals, psychiatric organizations, care organizations for mentally disabled people, home care organizations, nursing homes or homes for the elderly.</p> <p>Results</p> <p>Half of the respondents were confronted with the introduction of a new technology in the last three years. Only half of these rated the introduction of the technology as positive.</p> <p>The factors most frequently mentioned as impeding actual use were related to the (kind of) technology itself, such as malfunctioning, ease of use, relevance for patients, and risks to patients. Furthermore nursing staff stress the importance of an adequate innovation strategy.</p> <p>Conclusions</p> <p>A prerequisite for the successful introduction of new technologies is to analyse determinants that may impede or enhance the introduction among potential users. For technological innovations special attention has to be paid to the (perceived) characteristics of the technology itself.</p
Vergelijkend onderzoek naar de arbeidsomstandigheden in de substraatteelt en de teelt in de grond : een orienterend onderzoek naar gezondheidsbedreigende factoren in het kasmilieu en een gerichte studie naar de blootstelling aan Lannate
Van de 3 bedrijfskenmerken: teeltwijze (grond- of steenwolteelt), gewasbehandeling (verspuiten of verstuiven van Lannate) en gewas (tomaten of komkommers), is onderzocht in hoeverre deze van invloed zijn op de blootstelling van werkers in de glastuinbouw. Daartoe is in 6 bedrijfssituaties gemeten met elk een andere combinatie van de bedrijfskenmerken. De dosering varieerde van 0,7 tot 5,6 kg Lannate per ha. De blootstelling aan Lannate tijdens het oogsten van komkommers en tomaten is onderzoch
Machine learning in intensive care medicine: ready for take-off?
In 1986 the world was shaken by the Challenger space shuttle disaster. In the years that followed, the American National Aeronautics and Space Administration (NASA) called for a strategy change in space technology development [1]. Allowing technology to be developed without a specific space program in mind was central to the new strategy [2]. In order to evaluate resulting projects with no direct contribution to a space mission, NASA introduced the general concept of technology readiness levels (TRLs) [3]. These nine levels, adopted by many EU institutions, assess the maturity level of technology and estimate its readiness to fly
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