Reducing Production Downtime Using Delay-Time Analysis

This paper reports on a study in which delay-time analysis and snapshot modelling are jointly applied to model the downtime consequences of a high-speed production line maintained under an inspection system. It is seen that the model is capable of producing results in acceptable agreement with observation and, further, that the technique can be used to predict an efficient inspection frequency for existing plant and also for modified plant yet to be installed.     

Determination of dγ/dT for water by means of a differential technique

The temperature derivative of the surface tension of water has been measured by means of the Wilhelmy method using an electrobalance and a differential technique. No anomalies were observed; −dγ/dT was found to be a slowly increasing linear function of T within the temperature range 5–40°C.     

Equipment Replacement in an Unsteady Economy

The decision problem concerning the replacement of members of a fleet of fork lift trucks during a period of inflation and economic uncertainty is considered. Based upon the analysis of data collected over a 2 year period of considerable inflation, a model of the expected operating costs for a truck is developed. The usual replacement criteria are not applicable here and an alternative criterion function based upon relatively short term estimates of costs and discount rate is presented. Using this function, the replacement decision is determined for both constant and variable discount rate situations.     

An Aminated GDP-Fucose Analog Useful in the Fucosyltransferase Catalyzed Addition of Biological Probes onto Oligosaccharide Chains1

Abstract

An analog (1) of GDP-fucose, where C-6 is derivatized with an eight-atom spacer terminating in a primary amino group, was chemically synthesized. This amino group in sugar nucleotide 1 can be acylated using an N-hydroxysuccinimide ester of biotin and it can be coupled to another molecule that also contains an amino group using squaric acid diethyl ester as the coupling reagent. In this way, biotin and a blood group A-active trisaccharide were linked to C-6 of fucose in GDP-fucose. Both complex sugar nucleotides thus prepared were active as donors for a human milk fucosyltransferase, which transferred the derivatized α-linked fucose residue to a glycoside of N-acetyllactosamine, thus labeling this sequence with either biotin or the blood-group A trisaccharide. Compound 1 is proposed as a general and versatile reagent which should permit the addition of biological probes to the sugar chains of cell surface glycoproteins or glycolipids.     

C-pentyltetra(3-pyridyl)cavitand: a versatile building block for the directed assembly of hydrogen-bonded heterodimeric capsules

Hydrogen-bond-directed assembly of heterodimeric cavitand-based capsules is of considerable interest. Herein, we report the synthesis and single-crystal X-ray structure determination of a pyridyl-functionalized cavitand that contains suitable hydrogen-bond acceptor moieties for the construction of asymmetric cavitand-based capsules. [structure: see text]     

Real-time detection of cofactor availability in genetically modified living Saccharomyces cerevisiae cells — Simultaneous probing of different geno- and phenotypes

This work describes a mediated amperometric method for simultaneous real-time probing of the NAD(P)H availability in two different phenotypes, fermentative and respiratory, of the phosphoglucose isomerase deletion mutant strain of S. cerevisiae, EBY44 [ENY.WA-1A pgi1-1D::URA3], and its parental strain, ENY.WA-1A. The developed method is based on multichannel detection using microelectrode arrays. Its versatility was demonstrated by using four microelectrode arrays for simultaneously monitoring the NAD(P)H availability of both geno- and phenotypes under the influence of two different carbon sources, glucose and fructose, as well as the cytosolic and mitochondrial inhibitor and uncoupler, dicoumarol. The obtained results indicate that the method is capable of accurately and reproducibly (overall relative standard error of mean 3.2%) mapping the real-time responses of the cells with different genotype–phenotype combinations. The ENY.WA cells showed the same response to glucose and fructose when dicoumarol was used; fermentative cells indicated the presence of cytosolic inhibition and respiratory cells a net effect of mitochondrial uncoupling. EBY44 cells showed cytosolic inhibition with the exception of respiratory cells when fructose was used as carbon source.     

Integral inequalities for generalized concave or convex functions

Let ψ be convex with respect to ?, B a convex body in Rⁿ and f a positive concave function on B. A well-known result by Berwald states that $\text{1}\text{¦B¦}\text{∝}{}_{\mathrm{B}}\text{ψ(f(x)) dx ? n ∝}{}_0{}^1\text{ψ(ξt)(1 ? t)}{}^{\mathrm{n\; ?\; 1)}}\text{dt}$ (1) if ξ is chosen such that $\text{1}\text{¦B¦}\text{∝}{}_{\mathrm{B}}\text{?(f(x)) dx = n ∝}{}_0{}^1\text{?(ξt)(1 ? t)}{}^{\mathrm{n\; ?\; 1)}}\text{dt}$.The main purpose in this paper is to characterize those functions f : B → R₊ such that (1) holds.     

A new algorithm for meromorphic Nevanlinna-Pick interpolation

Summary. Let D be be the open unit disc, H₀ the space of all bounded analytic functions in D and H_k the set of all functions of the form f(z)/(z–z₁)...(z–z_k) where z₁,...,z_k D and f H₀. Given {z₁,...,z_n},{w₁,...,w_n}, where z_i D,w_i and z_iz_j if ij, we show for 0kn–1, under certain assumptions, how to construct the unique interpolating function B_kH_k, B_k(z_j)=w_j, of minimal essential supremum norm on D by solving an eigenvalue problem defined by the interpolation data. The function B_k is a scaled quotient of two finite Blaschke products.Mathematics Subject Classification (2000): 65E05, 30D50, 30E05Acknowledgement We are very indebted to Professor Martin Gutknecht for pointing out the necessity of Assumption A and for providing us with a translation of [A]. Also valuable discussions with Professors Olof Staffans and Göran Högnäs are acknowledged. The research of the second named author was supported by the Academy of Finland Project 51906.