Valuation of functions of the Wadden Area

The rationale of this position paper is to explore ways to employ valuation methods to assess the impacts of alternative policy decisions on the functions of the Wadden Area. Based on this rationale, this paper aims to bring an ecological-economic perspective on the benefits of the Wadden Area. It highlights key issues involved in the notion and application of monetary valuation methods for valuing the (ecological) functions of the area. It also pays attention to the development of policy handles on the basis of the outcome of the valuation of ecological functions. Particularly, the paper discuss Payment for Environmental Services (PES), which aims at preservation and protection by purchasing conservation. The use of a valuation instrument within a Payment for Environmental Services Scheme is new. Valuation is of course an established technique within a Cost-Benefit framework. However, Payment for Environmental Services is an innovative way of designing policy instruments in the collaboration between ecologists and economist

Predicting the occurrence of sand banks in the North Sea

Sand banks have a wavelength between 1 and 10 km, and they are up to several tens of meters high. Also, sand banks may have an impact on large-scale human activities that take place in the North Sea like sand mining, shipping, offshore wind farms, etc. Therefore, it is important to know where sand banks occur and what their natural behavior is. Here, we use an idealized model to predict the occurrence of sand banks in the North Sea. The aim of the paper is to research to what extent the model is able to predict the occurrence of sand banks in the North Sea. We apply a sensitivity analysis to optimize the model results for a North Sea environment. The results show that the model correctly predicts whether or not sand banks occur for two thirds of the North Sea area

The Sa'dan Toradja Chant for the Deceased

Indonesi

OH-selected AGB and post-AGB objects I.Infrared and maser properties

Using 766 compact objects from a survey of the galactic Plane in the 1612-MHz OH line, new light is cast on the infrared properties of evolved stars on the TP-AGB and beyond. The usual mid-infrared selection criteria, based on IRAS colours, largely fail to distinguish early post-AGB stages. A two-colour diagram from narrower-band MSX flux densities, with bimodal distributions, provides a better tool to do the latter. Four mutually consistent selection criteria for OH-masing red PPNe are given, as well as two for early post-AGB masers and one for all post--AGB masers, including the earliest ones. All these criteria miss a group of blue, high-outflow post-AGB sources with 60-mum excess; these will be discussed in detail in Paper II. The majority of post-AGB sources show regular double-peaked spectra in the OH 1612-MHz line, with fairly low outflow velocities, although the fractions of single peaks and irregular spectra may vary with age and mass. The OH flux density shows a fairly regular relation with the stellar flux and the envelope optical depth, with the maser efficiency increasing with IRAS colour R21. The OH flux density is linearly correlated with the 60-mum flux density.Comment: 16 pages, LaTex, 22 figures, AJ (accepted

Isolated lateral extra-articular tenodesis enhance better rotatory knee joint stability post-primary ACL repair:Four cases report and literature review

INTRODUCTION AND IMPORTANCE: Residual rotatory instability has been reported to occur after primary anterior cruciate ligament reconstruction. The anterolateral ligament complex of the knee has gained attention for its role in rotational instability of the knee, especially in association with anterior cruciate ligament injuries. The role of an isolated lateral extra-articular tenodesis procedure among those patients presenting with residual rotatory instability after primary anterior cruciate ligament reconstruction has not been reported on. CASE PRESENTATION: Four patients (Tegner level 4) presenting with residual rotatory instability after primary anterior cruciate ligament reconstruction without signs of graft failure, underwent an isolated lateral extra-articular tenodesis with modified Lemaire procedure. Pre- and postoperative outcome scores were assessed. At one-year follow-up, all patients reported functional knee stability. Pivot shift tests were negative and postoperative Lysholm scores were increased with a mean of 19.75 points. Tegner scores equaled the preinjury level. CLINICAL DISCUSSION: This case report showed that our four patients where successfully treated with an isolated secondary modified Lemaire procedure for residual anterolateral rotatory instability after primary anterior cruciate ligament reconstruction. CONCLUSION: An isolated secondary lateral extra-articular tenodesis procedure can be a valuable treatment option for moderate active patients with residual rotatory instability after a primary anterior cruciate ligament reconstruction without signs of graft failure

An Attempt to Detect the Galactic Bulge at 12 microns with IRAS

Surface brightness maps at 12 microns, derived from observations with the Infrared Astronomical Satellite (IRAS), are used to estimate the integrated flux at this wavelength from the Galactic bulge as a function of galactic latitude along the minor axis. A simple model was used to remove Galactic disk emission (e.g. unresolved stars and dust) from the IRAS measurements. The resulting estimates are compared with predictions for the 12 micron bulge surface brightness based on observations of complete samples of optically identified M giants in several minor axis bulge fields. No evidence is found for any significant component of 12m emission in the bulge other than that expected from the optically identified M star sample plus normal, lower luminosity stars. Known large amplitude variables and point sources from the IRAS catalogue contribute only a small fraction to the total 12 micron flux.Comment: Accepted for publication in ApJ; 13 pages of text including tables in MS WORD97 generated postscript; 3 figures in postscript by Sigma Plo

'Calving laws', 'sliding laws' and the stability of tidewater glaciers

A new calving criterion is introduced, which predicts calving where the depth of surface crevasses equals ice height above sea level. Crevasse depth is calculated from strain rates, and terminus position and calving rate are therefore functions of ice velocity, strain rate, ice thickness and water depth. We couple the calving criterion with three 'sliding laws', in which velocity is controlled by (1) basal drag, (2) lateral drag and (3) a combination of the two. In model 1, velocities and strain rates are dependent on effective pressure, and hence ice thickness relative to water depth. Imposed thinning can lead to acceleration and terminus retreat, and ice shelves cannot form. In model 2, ice velocity is independent of changes in ice thickness unless accompanied by changes in surface gradient. Velocities are strongly dependent on channel width, and calving margins tend to stabilize at flow-unit widenings. Model 3 exhibits the combined characteristics of the other two models, and suggests that calving glaciers are sensitive to imposed thickness changes if basal drag provides most resistance to flow, but stable if most resistance is from lateral drag. ice shelves can form if reduction of basal drag occurs over a sufficiently long spatial scale. In combination, the new calving criterion and the basal-lateral drag sliding function (model 3) can be used to simulate much of the observed spectrum of behaviour of calving glaciers, and present new opportunities to model ice-sheet response to climate change.</p