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An automated on-line monitoring system for low-molecular-weight compounds (e.g. sugars) during fermentation processes is described. The applicability of cross-flow ultrafiltration, coupled on-line with high-performance liquid chromatography, is evaluated. Various detection modes for the determination of the test compounds lactose, glucose and fructose) in a complex fermentation broth are compared. In addition, the influence of some system parameters on the performance of several ultrafiltration modules for the removal of cellular and macromolecular broth constituents is investigated. A method for the fully automated determination of sugars during anE. coli batch culture in a brain-heart infusion medium is presented. With the present system five analyses can be performed every hour, using only 35μl of sample, without significant deterioration of the ultrafiltration process. Contamination by external micro-organisms was not observed and good correlation with an off-line method was found.

Many insurers offer policies which provide a combination of insurance coverage up to a fixed retirement age and an annuity income after retirement. Premiums are normally payable until the retirement age is reached. The retirement income is often at the rate of $10 per month for each $1000 of face amount and is customarily payable for a fixed number of years certain and the remainder of life. Under normal circumstances the present value at the retirement age of the annuity income of $10 per month exceeds the face amount of $1000. This means that the policy must nature at the retirement age for an amount greater than the face amount, and that the policy reserves and cash values, in building up to the required maturi ty value, will also exceed the face amount for a period prior to retirement. Since it is impractical to have the face amount of insurance loss than the cash value, these policies provide that the death benefit will be equal to the cash value during the period when the cash value exceeds the face amount. Let 1 ~ k denote the present value at the retirement age, x ~ n, of the annuity to be provided at that age for each unit of face amount issued at age x. Then the policy can be regarded as a combination of a pure endowment of 1 ~ k due at the retirement age and a term insurance up to that age providing a death benefit equal to 1 or the total cash value on the policy whichever is greater. The net premium, P, for tho policy can therefore be written

Die Verfasser besprechen kritisch die dem 19. IKVM vorgelegten VorschlAge fur eine Reform der internationalen versicherungsmathematischen Bezeichnungsweise, vor allem den Vorschlag von Adam, Boehm u. a. Haupteinwand gegen letzteren ist, da\ die Funktionsnamen erst zusammen mit der —ofters komplizierten —Parameterliste eindeutig die Funktion kennzeichnen. Ziel der Arbeit ist nachzuweisen, da\ eine Veroffentlichungssprache moglich ist, die Der Nachweis hierfur wird fur versicherungsmathematische Funktionen auf ein und mehrere Leben in einem erweiterten Funktionsbereich erbracht. Anschlie\end wird die entwickelte Ver offentlichungssprache auf Funktionen der allgemeinen Markoffschen Versicherung und der BerufsunfAhigkeitsversicherung angewendet. Die Transformation der Veroffentlichungssprache in eine Computersprache ist bei Eindeutigkeit der Funktionsnamen ein einfaches Problem; es wird durch ein System von Transformationsregeln gelost. The authors discuss the various proposals for the reform of the international actuarial notation which were presented at the 19th International Congress of Actuaries, with particular attention to the paper submitted by Adam, Boehm a.o. The main objection to the latter is that the names of functions only clearly define the functions themselves with the aid of the (sometimes com plicated) parameter lists. The aim of the article is to prove that it is possible to invent an actuarial notation system which The proof of this is presented with the aid of a number of actuarial functions for one and more lives covering an extended area. The proposed new notation system is then applied to functions for the general technique of Markov insurance and for disability insurance. The transformation of the actuarial notation system into a computer language is a simple problem if the function names are clearly defined; it can be solved by a system of transformation rules.

1. Function names in a computer language have to be unique. 2. Direct transformation of the function names of the present notation into computer names seems highly impracticable. 3. Computer names are not usable for publication purposes by lag of mnemotechnical facilities. 4. An intermediary linearized system of unique function names with a maximum of mnemotechnical facilities and offering the possibility of extending the field of an international notation may be advisable. Other than technical aspects may play a role in the decision to be taken. 5. It seems possible to develop a language satisfying the demands formulated in 4.

Using as their starting point the work by a group of German speaking actuaries described in a paper published in the Transactions of the 18th I.C.A. (Vol. II, p. 815), Munich, 1968, a working party of European actuaries from eight countries prepared proposals for modernising the actuarial notation. The proposed International Actuarial Publication Language extends beyond compound interest and life assurance to pension fund and sickness insurance functions and is based on the following principles: (a) exclusive use of an internationally established set of characters; (b) linear arrangements of these characters to denote actuarial values and functions; (c) unequivocality, consistency, and, as far as possible, completeness; (d) preservation of the basic concepts and symbols of the present actuarial notation within the framework of these principles, together with the closest possible conformity to modern mathematical notation; (e) attention to the requirements of mechanical reproduction.