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141.
Jeroen M. van Oostrum Eelco Bredenhoff Erwin W. Hans 《Annals of Operations Research》2010,178(1):91-104
Operating room (OR) planning and scheduling is a popular and challenging subject within the operational research applied to
health services research (ORAHS). However, the impact in practice is very limited. The organization and culture of a hospital
and the inherent characteristics of its processes impose specific implementation issues that affect the success of planning
approaches. Current tactical OR planning approaches often fail to account for these issues. Master surgical scheduling (MSS)
is a promising approach for hospitals to optimize resource utilization and patient flows. We discuss the pros and cons of
MSS and compare MSS with centralized and decentralized planning approaches. Finally, we address various implementation issues
of MSS and discuss its suitability for hospitals with different organizational foci and culture. 相似文献
142.
The coupling coefficients describing the linear Γ 9× (g+2h) Jahn–Teller Hamiltonian in icosahedral symmetry are derived, and various coupling schemes are discussed. 相似文献
143.
This paper is concerned with the class of linear partial differential equations of second order such that there exist Bergman operators with polynomial kernels (cf, [12]). In an earlier paper [ll] the authors have shown that these equations also admit differential operators as introduced by K. W. Bauer [I]. In the present paper, relations between different types of representations of solutions are investigated. These representations are of interest in developing a function theory of solutions; cf., for instance, K. W. Bauer [I] and S. Ruscheweyh [19]. They are also essential to global extensions of local results obtained by means of Bergman operators of the first kind. The inversion problem for those operators is solved, and it is shown that all solutions of equations of that class which are holomorphic in a domain of C2 can be represented by operators with polynomial kernels. Furthermore, a construction principle for deriving the equations investigated by K. W. Bauer [2] is obtained; this yields corresponding representations of solutions by differential and integral operators in a systematic fashion 相似文献
144.
In this article we study various convergence results for a class of nonlinear fractional heat equations of the form $\left\{ \begin{gathered} u_t (t,x) - \mathcal{I}[u(t, \cdot )](x) = f(t,x),(t,x) \in (0,T) \times \mathbb{R}^n , \hfill \\ u(0,x) = u_0 (x),x \in \mathbb{R}^n , \hfill \\ \end{gathered} \right.$ where I is a nonlocal nonlinear operator of Isaacs type. Our aim is to study the convergence of solutions when the order of the operator changes in various ways. In particular, we consider zero order operators approaching fractional operators through scaling and fractional operators of decreasing order approaching zero order operators. We further give rate of convergence in cases when the solution of the limiting equation has appropriate regularity assumptions. 相似文献
145.
Melanie Miller William E. Robinson Ana Rita Oliveira Nina Heidary Nikolay Kornienko Julien Warnan Inês A. C. Pereira Erwin Reisner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(14):4649-4653
The integration of enzymes with synthetic materials allows efficient electrocatalysis and production of solar fuels. Here, we couple formate dehydrogenase ( FDH ) from Desulfovibrio vulgaris Hildenborough (DvH) to metal oxides for catalytic CO2 reduction and report an in‐depth study of the resulting enzyme–material interface. Protein film voltammetry (PFV) demonstrates the stable binding of FDH on metal‐oxide electrodes and reveals the reversible and selective reduction of CO2 to formate. Quartz crystal microbalance (QCM) and attenuated total reflection infrared (ATR‐IR) spectroscopy confirm a high binding affinity for FDH to the TiO2 surface. Adsorption of FDH on dye‐sensitized TiO2 allows for visible‐light‐driven CO2 reduction to formate in the absence of a soluble redox mediator with a turnover frequency (TOF) of 11±1 s?1. The strong coupling of the enzyme to the semiconductor gives rise to a new benchmark in the selective photoreduction of aqueous CO2 to formate. 相似文献
146.
Dr. Stefan van der Vorm Thomas Hansen Dr. Erwin R. van Rijssel Rolf Dekkers Jerre M. Madern Prof. Dr. Herman S. Overkleeft Dr. Dmitri V. Filippov Prof. Dr. Gijsbert A. van der Marel Dr. Jeroen D. C. Codée 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(29):7149-7157
The 3D shape of glycosyl oxocarbenium ions determines their stability and reactivity and the stereochemical course of SN1 reactions taking place on these reactive intermediates is dictated by the conformation of these species. The nature and configuration of functional groups on the carbohydrate ring affect the stability of glycosyl oxocarbenium ions and control the overall shape of the cations. We herein map the stereoelectronic substituent effects of the C2-azide, C2-fluoride and C4-carboxylic acid ester on the stability and reactivity of the complete suite of diastereoisomeric furanoses by using a combined computational and experimental approach. Surprisingly, all furanosyl donors studied react in a highly stereoselective manner to provide the 1,2-cis products, except for the reactions in the xylose series. The 1,2-cis selectivity for the ribo-, arabino- and lyxo-configured furanosides can be traced back to the lowest-energy 3E or E3 conformers of the intermediate oxocarbenium ions. The lack of selectivity for the xylosyl donors is related to the occurrence of oxocarbenium ions adopting other conformations. 相似文献
147.
148.
Adissu Alemayehu Asfaw Juan Aspromonte Kris Wolfs Ann Van Schepdael Erwin Adams 《Journal of separation science》2019,42(1):214-225
Sample preparation and introduction techniques are very critical steps in gas chromatography analysis and particularly in the analysis of volatiles in solid samples. In these cases, they can be divided into two main categories: direct and indirect approaches, based on how the solid sample is treated, i.e. with and without dissolution (or extraction) of analytes from the solid sample. To enable routine application, coupling with sample preparation techniques (especially solid or solvent‐based microextractions) is needed to achieve automation. Here, an overview of the most common sample introduction techniques for gas chromatography with their advantages and drawbacks is presented and discussed, including references to relevant examples. So, this review can serve as guidance for new users. 相似文献
149.
Maartje M. C. Bastings Thomas M. Hermans A. J. H. Spiering Erwin W. L. Kemps Lorenzo Albertazzi Eva E. Kurisinkal Patricia Y. W. Dankers 《Macromolecular bioscience》2019,19(1)
The most basic function of synthetic microenvironments for tissue engineering is to act as a physical substrate for cell attachment, migration, and proliferation, similar to the natural cell environment. Functionalization of supramolecular materials with guest compounds that display the same recognition moieties is a common strategy to introduce biofunctionality. However, besides a robust interaction with the material, a certain level of dynamics needs to be conserved for an adaptive interface toward the living environment. A balance between robust material functionalization and dynamic cell interaction needs to be met. The detailed analysis hereof using a ureido‐pyrimidinone (UPy) poly(ethylene glycol) system in dilute and transient network regime is demonstrated. Monovalent and bivalent UPy‐functionalized guest molecules are designed and their interaction with UPy‐host fibers is evaluated. Analysis of guest interaction in the dilute state by microfluidics, and in the gel state, by fluorescence recovery after photobleaching and fluorescence resonance energy transfer is proven to be suitable to quantify the local and ensemble guest mobility. The results demonstrate that the interaction of bioactive moieties through supramolecular host–guest chemistry yields a dynamic system, which is stronger for divalent guests but risks unintended leakage in the case of functional monomeric units. 相似文献
150.
The transport of an infinitely thin, hard rod in a random, dense array of point obstacles is investigated by molecular dynamics simulations. Our model mimics the sterically hindered dynamics in dense needle liquids. Transport becomes increasingly fast at higher densities, and we observe a power-law divergence of the diffusion coefficient with exponent 0.8. This phenomenon is connected with a new divergent time scale, reflected in a zigzag motion of the needle, a two-step decay of the velocity-autocorrelation function, and a negative plateau in the non-Gaussian parameter. Finally, we provide a heuristic scaling argument for the new exponent. 相似文献