Medisch ethische beschouwingen over orgaantransplantatie

De medische kennis is in de laatste decennia aanzienlijk vergroot. Deze kennistoeneming is gepaard gegaan met een vermeerdering van het medisch kunnen. Nieuwe theorieën gingen vergezeld van nieuwe mogelijkheden. Zo is ook de orgaantransplantatie tot grote bloei gekomen door beheersing van de heelkundige techniek, maar vooral ook van de immunologische afweermechanismen. Een geheel.nieuw veld is opengelegd. Het is geboden om naast het juichen over deze vorderingen ook kritisch stil te staan en zich af te vragen: wat doen wij? Is het in medisch-ethisch opzicht geoorloofd om zo te handelen? En overschrijden wij de grenzen van het toelaatbare niet? In een aantal hoofdstukjes zullen wij ons hierop bezinnen

Asymptotic inference for nearly unstable AR(p) processes

In this paper nearly unstable AR( p) processes (in other words, models with characteristic roots near the unit circle) are studied. Our main aim is to describe the asymptotic behavior of the least-squares estimators of the coefficients. A convergence result is presented for the general complex-valued case, The limit distribution is given by the help of some continuous time AR processes. We apply the results for real-valued nearly unstable AR(p) models. In this case the limit distribution can be identified with the maximum likelihood estimator of the coefficients of the corresponding continuous time AR processes

Bifurcation at nonsemisimple 1: - 1 resonance

In this paper a description is given of the bifurcation of periodic solutions occurring when a Hamiltonian system of two degrees of freedom passes through nonsemisimple 1–1 resonance at an equilibrium. A bifurcation like this is found in the planar circular restricted problem of three bodies at the Lagrange equilibriumL 4 when the mass parameter passes through the critical value of Routh. Gegenstand dieses Artikels ist die Verzweigung periodischer Lösungen in Hamilton''schen Systemen mit zwei Freiheitsgraden beim Durchgang durch eine nicht-einfache 1–1-Resonanz an einem Gleichgewicht. Ein Beispiel ist das ebene restringierte Dreikörperproblem am Lagrange-PunktL 4, wenn die Masse durch den kritischen Wert von Routh hindurchgeht

An Alternate Method for Fourier Transform Infrared (FTIR) Spectroscopic Determination of Soil Nitrate Using Derivative Analysis and Sample Treatments

This study aimed at examining effective sample treatments and spectral processing for an alternate method of soil nitrate determination using the attenuated total reflectance (ATR) of Fourier transform infrared (FTIR) spectroscopy. Prior to FTIR measurements, soil samples were prepared as paste to enhance adhesion between the ATR crystal and sample. The similar nitrate peak heights of soil pastes and their supernatants indicated that the nitrate in the liquid portion of the soil paste mainly responded to the FTIR signal. Using a 0.01-M CaSO4 solution for the soil paste, which has no interference bands in the characteristic spectra of the analyte, increased the concentration of the nitrates to be measured. Second-order derivatives were used in the prediction model to minimize the interference effects and enhance the performance. The second-order derivative spectra contained a unique nitrate peak in a range of 1,400-1,200 cm(-1) without interference of carbonate. A partial least square regression model using second-order derivative spectra performed well (R (2) = 0.995, root mean square error (RMSE) = 23.5, ratio of prediction to deviation (RPD) = 13.8) on laboratory samples. Prediction results were also good for a test set of agricultural field soils with a CaCO3 concentration of 6% to 8% (R (2) = 0.97, RMSE = 18.6, RPD = 3.5). Application of the prediction model based on soil paste samples to nitrate stock solution resulted in an increased RMSE (62.3); however, validation measures were still satisfactory (R (2) = 0.99, RPD = 3.0

Spontaneous Ratchet Effect in a Granular Gas

The spontaneous clustering of a vibrofluidized granular gas is employed to generate directed transport in two different compartmentalized systems: a "granular fountain" in which the transport takes the form of convection rolls, and a "granular ratchet" with a spontaneous particle current perpendicular to the direction of energy input. In both instances, transport is not due to any system-intrinsic anisotropy, but arises as a spontaneous collective symmetry breaking effect of many interacting granular particles. The experimental and numerical results are quantitatively accounted for within a flux model.Comment: 4 pages, 5 figures; Fig. 4 has been reduced in size and qualit

NOTES ON THE FAUNA OF PULAU BERHALA

ABSTRACT NOT AVAILABL

A NOTE ON TWO SPECIES OF MALAYSIAN KING-CRABS (XIPHOSURA)

abstract not availabl

Corrections to: \'Constrained normalization of Hamiltonian systems and perturbed Keplerian motion\'

Consider a Hamiltonian system (H, 2n ,). LetM be a symplectic submanifold of (2n ,). The system (H, 2n ,) constrained toM is (HM, M, M). In this paper we give an algorithm which normalizes the system on 2n in such a way that restricted toM we have normalized the constrained system. This procedure is then applied to perturbed Kepler systems such as the lunar problem and the main problem of artificial satellite theory. Wir betrachten ein Hamiltonisches System (H, 2n ,). SeiMein symplectisches Submanifold von (2n ,). Das System (H, 2n ,), aufM beschränkt, ist (HM,M,M). In der vorliegenden Arbeit wird ein Algorithmus vorgeschlagen, der dieses System so auf 2n normalisiert, daß das aufM beschränkte System auch normalisiert ist. Dieser Algorithmus wird dann auf gestörte Keplersysteme, wie z. B. das Hill-sche Mondproblem und das Hauptproblem der Theorie der künstlichen Satelliten, angewendet