Allocating service parts in two-echelon networks at a utility company

We study a multi-item, two-echelon, continuous-review inventory problem at a Dutch utility company, Liander. We develop a model that optimizes the quantities of service parts and their allocation in the two-echelon network under an aggregate waiting time restriction. Specific aspects that we address are emergency shipments in case of stockout, and batching for regular replenishment orders at the central warehouse. We use column generation as a basic technique to solve this problem, and use various building blocks for single-item models as columns. Further, we study options to derive simple classification rules from the solution of our multi-item, two-echelon service part optimization problem using statistical techniques. Application of our models at Liander yields a solution that reduces costs by 15% and decreases the impact of waiting time for service parts by 52%

L'utilisation D'analyses Faecales Pour EstiMer L'absorption En Phosphore De Moutons En Pature. I. L'utilisation D'un Echantillonage En Masse A La Place D'echantillons Individuels

Analyses of rectal faeces of sheep for phosphorus, calcium and magnesium may be useful to indicate the mineral status of the herbage being consumed. A number of sheep should be used for each pasture, but this would entail a large number of individual analyses. In this experiment it was shown that a pool analysis of faeces did not differ significantly (P < 0, 01) from the arithmetic mean of the individual samples (20). In 13 replications this was true for phosphorus, calcium and magnesium, whether the sheep were non-pregnant, non-lactating, pregnant, or lactating. From the results it was estimated that 3 faecal pellets from at least 30 sheep should be used to make the pool. Blood was also taken on 11 occasions for pool and individual (20) analyses. No significant difference was found for plasma inorganic phosphate, magnesium and total protein, but on 3 occasions there was a significant difference (P< 0, 01) for plasma calcium.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Quantitative considerations in medium energy ion scattering depth profiling analysis of nanolayers

The high depth resolution capability of medium energy ion scattering (MEIS) is becoming increasingly relevant to the characterisation of nanolayers in e.g. microelectronics. In this paper we examine the attainable quantitative accuracy of MEIS depth profiling. Transparent but reliable analytical calculations are used to illustrate what can ultimately be achieved for dilute impurities in a silicon matrix and the significant element-dependence of the depth scale, for instance, is illustrated this way. Furthermore, the signal intensity-to-concentration conversion and its dependence on the depth of scattering is addressed. Notably, deviations from the Rutherford scattering cross section due to screening effects resulting in a non-coulombic interaction potential and the reduction of the yield owing to neutralization of the exiting, backscattered H+ and He+ projectiles are evaluated. The former mainly affects the scattering off heavy target atoms while the latter is most severe for scattering off light target atoms and can be less accurately predicted. However, a pragmatic approach employing an extensive data set of measured ion fractions for both H+ and He+ ions scattered off a range of surfaces, allows its parameterization. This has enabled the combination of both effects, which provides essential information regarding the yield dependence both on the projectile energy and the mass of the scattering atom. Although, absolute quantification, especially when using He+, may not always be achievable, relative quantification in which the sum of all species in a layer add up to 100%, is generally possible. This conclusion is supported by the provision of some examples of MEIS derived depth profiles of nanolayers. Finally, the relative benefits of either using H+ or He+ ions are briefly considered

Weight loss and elevated gluconeogenesis from alanine in lung cancer patients

BACKGROUND: The role of gluconeogenesis from protein in the pathogenesis of weight loss in lung cancer is unclear. OBJECTIVE: Our aim was to study gluconeogenesis from alanine in lung cancer patients and to analyze its relation to the degree of weight loss. DESIGN: In this cross-sectional study, we used primed-constant infusions of [6,6-(2)H(2)]-D-glucose and [3-(13)C]-L-alanine to assess whole-body glucose and alanine turnover and gluconeogenesis from alanine in weight-losing (WL, n = 9) and weight-stable (WS, n = 10) lung cancer patients and healthy control (n = 15) subjects. RESULTS: Energy intake and plasma alanine concentrations did not differ significantly among the subject groups. Mean (+/-SEM) whole-body glucose production was significantly higher in WL than in WS and control subjects (0.74 +/- 0.06 compared with 0.55 +/- 0.04 and 0.51 +/- 0.04 mmol*kg(-)(1)*h(-)(1), respectively, P < 0.01). Alanine turnover was significantly elevated in WL compared with WS and control subjects (0.57 +/- 0.04 compared with 0.42 +/- 0.05 and 0.40 +/- 0.03 mmol*kg(-)(1)*h(-)(1), respectively, P < 0.01). Gluconeogenesis from alanine was significantly higher in WL than in WS and control subjects (0.47 +/- 0.04 compared with 0.31 +/- 0.04 and 0.29 +/- 0.04 mmol*kg(-)(1)*h(-)(1), respectively, P < 0.01). The degree of weight loss was positively correlated with glucose and alanine turnover and with gluconeogenesis from alanine (r = 0.45 for all, P < 0.01). CONCLUSIONS: Aberrant glucose and alanine metabolism occurred in WL lung cancer patients. These changes were related to the degree of weight loss and not to the presence of lung cancer per se

Health related quality of life in patients with multiple myeloma undergoing a double transplantation

Objectives: To investigate the subjective well-being of patients with newly diagnosed multiple myeloma who were treated in a tandem transplantation programme. Methods: Fifty-one patients participated in the prospective, longitudinal questionnaire study. The EORTC QLQ-C30 and the EuroQol-5D were administered 2 wk after completion of vincristine, adriamycin and dexamethason/vincristine, adriamycin and methyl prednison (VAD/VAMP) chemotherapy, both at hospital discharge after treatment with high-dose melphalan (HDM) and 1 month after this hospital discharge, at hospital admission, at the day of hospital discharge for peripheral stem cell transplantation (PSCT) and at 6 and 12 months following discharge after PSCT. Results: Overall, patients' functioning improved during treatment and follow-up, with significant decreases shortly following PSCT. Shortly after HDM and PSCT, patients reported a considerable increase in levels of soreness in the mouth (+ 26/ + 36 points on a scale ranging form 0 to 100; P < 0.01), change of taste (+ 23/ + 21 points; P < 0.05/ NS), nausea/vomiting (+ 26

Automated entire thrombus density measurements for robust and comprehensive thrombus characterization in patients with acute ischemic stroke

Background and Purpose: In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements. Materials and Method: In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described usingmedians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between themedian of entire thrombusmeasurements and commonly applied manualmeasurements using 3 regions of interest were determined using linear regression. Results: Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density. Conclusions: Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, d

Two-year clinical follow-up of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN): Design and statistical analysis plan of the extended follow-up study

Background: MR CLEAN was the first randomized trial to demonstrate the short-term clinical effectiveness of endovascular treatment in patients with acute ischemic stroke caused by large vessel occlusion in the anterior circulation. Several other trials confirmed that endovascular treatment improves clinical outcome at three months. However, limited data are available on long-term clinical outcome. We aimed to estimate the effect of endovascular treatment on functional outcome at two-year follow-up in patients with acute ischemic stroke. Secondly, we aimed to assess the effect of endovascular treatment on major vascular events and mortality during two years of follow-up. Methods: MR CLEAN is a multicenter clinical trial with randomized treatment allocation, open-label treatment, and blinded endpoint evaluation. Patients included were 18 years or older with acute ischemic stroke caused by a proven anterior proximal artery occlusion who could be treated within six hours after stroke onset. The intervention contrast was endovascular treatment and usual care versus no endovascular treatment and usual care. The current study extended the follow-up duration from three months to two years. The primary outcome is the score on the modified Rankin scale at two years. Secondary outcomes include all-cause mortality and the occurrence of major vascular events within two years of follow-up. Discussion: The results of our study provide information on the long-term clinical effectiveness of endovascular treatment, which may have implications for individual treatment decisions and estimates of cost-effectiveness. Trial registration:NTR1804. Registered on 7 May 2009; ISRCTN10888758. Registered on 24 July 2012 (main MR CLEAN trial); NTR5073. Registered on 26 February 2015 (extended follow-up study)

The formation of cupper transition nano-layer in polytetrafluoroethylene surface by means of ion beam assisting deposition

The deposition of Cu on polytetrafluoroethylene surface assisted by the Ar ion beam with the temperature of 1 keV is investigated numerically. Ar ions provide the kinematic mixing of Cu atoms and atoms of substrate forming the connecting 10 nm layer of mixed material. This layer can ensure a good adhesion of Cu films deposited on polytetrafluoroethylene.Осаждение медного покрытия на поверхность политетрафторэтилена, стимулированное пучком ионов аргона с температурой 1 кэВ, изучалось методами численного моделирования. Ионы аргона обеспечивали смешивание атомов меди и поверхности, что позволило сформировать переходной слой шириной 10 нм. Такой слой может обеспечить хорошие адгезионные свойства металлической пленки, осажденной на поверхность политетрафторэтилена.Осадження мідного покриття на поверхню політетрафторетилену, стимульоване пучком іонів аргону з температурою 1 кеВ, вивчалось методами чисельного моделювання. Іони аргону забезпечували змішування атомів міді і поверхні, що дозволило сформувати перехідний шар шириною 10 нм. Такий шар може забезпечити гарні адгезійні властивості металевої плівки, обложеної на поверхню політетрафторетилену