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Detection and attribution of anthropogenic climate change signals in sea level rise (SLR) has experienced considerable attention during the last decades. Here we provide evidence that superimposed on any possible anthropogenic trend there is a significant amount of natural decadal and multidecadal variability. Using a set of 60 centennial tide gauge records and an ocean reanalysis, we find that sea levels exhibit long‐term correlations on time scales up to several decades that are independent of any systematic rise. A large fraction of this long‐term variability is related to the steric component of sea level, but we also find long‐term correlations in current estimates of mass loss from glaciers and ice caps. These findings suggest that (i) recent attempts to detect a significant acceleration in regional SLR might underestimate the impact of natural variability and (ii) any future regional SLR threshold might be exceeded earlier/later than from anthropogenic change alone. We find evidence for long‐term memory in MSL recordsLong‐term memory is found in the steric and mass componentsThis natural variability produces climate internal multidecadal trends

We introduce a new class of lifetime distributions exhibiting a notion of positive ageing, called the M-class, which is strongly related to the well-known L-class. It is shown that distributions in the M-class cannot have an undesirable property recently observed in an example of an L-class distribution by Klar (2002). Moreover, it is shown how these and related classes of life distributions can be characterized by expected remaining lifetimes after a family of random times, thus extending the notion of NBUE. We give examples of M-class distributions by using simple sufficient conditions, and we derive reliability bounds for distributions in this class.

We show an interesting identity for Ef(Y) − Ef(X), where X, Yare normally distributed random vectors and fis a function fulfilling some weak regularity condition. This identity will be used for a unified derivation of sufficient conditions for stochastic ordering results of multivariate normal distributions, some well known ones as well as some new ones. Moreover, we will show that many of these conditions are also necessary. As examples we will consider the usual stochastic order, convex order, upper orthant order, supermodular order and directionally convex order.

The optimal stopping value of random variables X1,…,Xndepends on the joint distribution function of the random variables and hence on their marginals as well as on their dependence structure. The maximal and minimal values of the optimal stopping problem is determined within the class of all joint distributions with fixed marginals F1,…,Fn. They correspond to some sort of strong negative or positive dependence of the random variables. Any value inbetween these two extremes is attained for some dependence structures. The determination of the minimal value is based on some new ordering results for probability measures, in particular on lattice properties of stochastic orderings. We also identify properties of dependence structures leading to the minimal optimal stopping value. In the proofs we need an extension of Strassen's theorem on representation of the convex order which reveals that convex ordered distributions can be coupled by a two-step martingale (X,Y) with the additional property that Yis stochastically increasing in X.

In this paper we solve two open problems posed by Joe (1997) concerning the supermodular order. First we give an example which shows that the supermodular order is strictly stronger than the concordance order for dimension d=3. Second we show that the supermodular order fulfils all desirable properties of a multivariate positive dependence order. We especially prove the non-trivial fact that it is closed with respect to weak convergence. This is applied to give a complete characterization of the supermodular order for multivariate normal distributions.

Experiments with merged beams of electrons and ions stored in accelerator rings have provided a wealth of new data on electron–ion collision processes. The development towards lower and lower temperatures of electron beams and the availability of brillant beams of ions up to the highest charge states has opened up a precision atomic spectroscopy through the observation of resonances. The available technology also provides unique new access to very low electron–ion collision energies. There, typically below a few millielectronvolts, an unexpected enhancement is observed in the recombination of atomic ions with electrons. For U28ions, where such enhancement was seen for the first time, the measured rate coefficient is roughly a factor of 200 higher than expectation for radiative recombination. The experimental spectrum can be simulated by assuming dielectronic recombination (DR) resonances at very low energies. However, recombination enhancements are also observed with completely stripped ions where no DR resonances can occur. Systematic studies of dependences of the new phenomenon on ion charge state, electron density and temperature, and on external electromagnetic fields are being carried out. So far, however, a satisfactory understanding is still missing.

AbstractIn this paper we investigate multivariate risk portfolios, where the risks are dependent. By providing some natural models for risk portfolios with the same marginal distributions we are able to compare two portfolios with different dependence structure with respect to their stop-loss premiums. In particular, some comparison results for portfolios with two-point distributions are obtained. The analysis is based on the concept of the so-called supermodular ordering. We also give some numerical results which indicate that dependencies in risk portfolios can have a severe impact on the stop-loss premium. In fact, we show that the effect of dependencies can grow beyond any given bound.

A brief review on the physics of electron-ion collisions is given. After an introduction focussing on the applied importance of electron-ion interactions a discussion of experimental techniques based on colliding beams of electrons and ions follows. The main part deals with the different types of electron-ion collision processes. An overview is provided on (1) electronimpact ionization of ions, (2) electron scattering from ions, (3) electron-impact excitation of ions, and (4) recombination of ions with free electrons.

We consider the problem of making one choice from a known number of i.i.d. alternatives. It is assumed that the distribution of the alternatives has some unknown parameter. We follow a Bayesian approach to maximize the discounted expected value of the chosen alternative minus the costs for the observations. For the case of gamma and normal distribution we investigate the sensitivity of the solution with respect to the prior distributions. Our main objective is to derive monotonicity and continuity results for the dependence on parameters of the prior distributions. Thus we prove some sort of Bayesian robustness of the model.

We consider probability metrics of the following type: for a class of functions and probability measures P, Qwe define A unified study of such integral probability metricsis given. We characterize the maximal class of functions that generates such a metric. Further, we show how some interesting properties of these probability metrics arise directly from conditions on the generating class of functions. The results are illustrated by several examples, including the Kolmogorov metric, the Dudley metric and the stop-loss metric.

We consider stochastic orders of the following type. Let be a class of functions and let Pand Qbe probability measures. Then define , if ? ? d P? ? ? d Qfor all fin . Marshall (1991) posed the problem of characterizing the maximal cone of functions generating such an ordering. We solve this problem by using methods from functional analysis. Another purpose of this paper is to derive properties of such integral stochastic ordersfrom conditions satisfied by the generating class of functions. The results are illustrated by several examples. Moreover, we show that the likelihood ratio order is closed with respect to weak convergence, though it is not generated by integrals.

Basic relations relevant to the observation of radiative recombination are presented and experiments on both spontaneous and laser-stimulated recombination of ions with free electrons are reviewed. In particular, the observation of unexpected high spontaneous recombination rates at very low energies is discussed. The fundamental and applied interest in the observed rate enhancement effects has recently triggered new experimental and theoretical work which can provide new insight into the problem of direct recombination of antiprotons with positrons to form antihydrogen.

An Handrädern von 16–77 cm ø wurden unter Variation der Höhe über dem Boden und der Winkelstellung zur Waagerechten das maximale Drehmoment, die maximale Drehzahl und der Energieverbrauch bei isometrischer und dynamischer Arbeit bestimmt. Für jede der untersuchten Größen gibt es scharf begrenzte Optima der Handradhöhe, die für das maximale Drehmoment und für die maximale Drehzahl bei einer bestimmten Winkelstellung vom Handraddurchmesser unabhängig sind. Die Optima für die 4 untersuchten Größen liegen bei gleicher Winkelstellung in verschiedener Handradhöhe. Das maximale Drehmoment wächst mit zunehmendem Handraddurchmesser, während die höchsten Drehzahlen mit Handrädern von 32–40 cm ø erreicht werden.

Zusammenfassung: Die arbeitsphysiologisch günstigste Schubkarrenform wurde am Beispiel einer althergebrachten schweren Holzkarre und neuerer Stahlkonstruktionen einer Mist- und einer Futterkarre untersucht.Vier Faktoren bestimmen den Energieaufwand und die Ermüdung beim Lastentransport mit einer Schubkarre.

Zusammenfassung: Die individuelle alveolare CO2-Spannung ist mitbestimmend für die Höhe des Grundumsatzes. Willkürliche Hyperventilation beeinflußt nur den Ruheumsatz, nicht dagegen den Arbeitsumsatz. Ein erheblicher Teil der beim Übergang vom Liegen zum Stehen festgestellten Zunahme des Energieumsatzes ist nicht durch Muskelarbeit verursacht, sondern ist die Folge der gleichzeitig zu beobachtenden Abnahme der alveolaren CO2-Spannung.

Zusammenfassung: Der Energieverbrauch für die Atemarbeit wurde bei willkürlicher Hyperventilation und konstanter alveolarer Kohlensäurespannung bestimmt. Im Bereich einer Ventilation von 6–22 Liter/Min. wurden etwa 1,7 ccm Sauerstoff je Liter Ventilation, im Bereich einer Ventilation von 22–40 Liter/Min. etwa 3,0 ccm Sauerstoff je Liter Ventilation verbraucht. Das sind 3,7 bzw. 5,4% des diesen Ventilationsgrößen entsprechenden Gesamtstoffwechsels.

Es ist gelungen, mit dem, dem Ninhydrin analog gebauten 1,2,3-Trioxo-2,3-dihydrophenalen (1), den Mechanismus der “Ninhydrinreaktion” aufzuklären.

Es wird gezeigt, daß das 3,3'-Dihydroxy-2,2'-bi-1-indenon (1), welchesMoubasher undIbrahim für den Ninhydrinfarbstoff halten, ein Sekundärprodukt desselben ist. Bei der katalytischen Hydrierung von 2-Nitro-1,3-indandion in Äthanol entsteht 6,12-Dioxo-6,12-dihydro-diindeno-pyrazin (3), während die Hydrolyse vonRuhemannpurpur (2) in ammoniakal. Lösung zum isomeren 5,7-Dioxo-5,7-dihydro-diindeno-pyrazin (5) führt.

Zusammenfassung Hyperglykämie fand sich in ausgesprochenem Maße beiDermatitis intertriginosa, beitertiärsyphilitischen Ulcerationen und in etwa der Hälfte der Fälle vonPsoriasis; in geringerem Maße beiFurunculose.