Managing economic and virtual economic capital within financial conglomerates.

In the present contribution we show how the optimal amount of economic capital can be derived such that it minimizes the economic cost of risk-bearing. The economic cost of risk-bearing takes into account the cost of the economic capital as well as the cost of the residual risk. In addition to the absolute problem of the determination of the amount of economic capital, we also consider the relative problem of how to establish the allocation of economic capital among subsidiaries. However, since subsidiaries are juridical entities they will also solve the problem of economic capital allocation themselves. Clearly, in an equilibrium situation the relative allocation derived by the conglomerate and the absolute allocation derived by the subsidiaries coincide. We show that the diversification benefit which is typically obtained in a conglomerate construction, creates a virtual economic capital for subsidiaries within the conglomerate. We show furthermore that the absolute allocation approach can also be applied to the problem of optimal portfolio selection, extending the well-known Markovitz approach and providing a tool for management by economic capital.Capital allocation; Construction; Equilibrium; Management; Optimal; Optimal portfolio selection; Portfolio; Risk; Risk management; Selection; Subsidiaries;

Some remarks on IBNR evaluation techniques.

In this short note we give some comments and general remarks on the methodology of IBNR computations, as presented at the workshop on IBNR computations at the 2000 ASTIN Meeting, Porto Cervo, Sardinia.Evaluation;

Highly efficient room temperature spin injection in a metal-insulator-semiconductor light emitting diode

We demonstrate highly efficient spin injection at low and room temperature in an AlGaAs/GaAs semiconductor heterostructure from a CoFe/AlOx tunnel spin injector. We use a double-step oxide deposition for the fabrication of a pinhole-free AlOx tunnel barrier. The measurements of the circular polarization of the electroluminescence in the Oblique Hanle Effect geometry reveal injected spin polarizations of at least 24% at 80K and 12% at room temperature

Electrical Spin Injection in a Ferromagnetic / Tunnel Barrier/ Semiconductor Heterostructure

We demonstrate experimentally the electrical ballistic electron spin injection from a ferromagnetic metal / tunnel barrier contact into a semiconductor III-V heterostructure. We introduce the Oblique Hanle Effect technique for reliable optical measurement of the degree of injected spin polarization. In a CoFe / Al2O3 / GaAs / (Al,Ga)As heterostructure we observed injected spin polarization in excess of 8 % at 80K.Comment: 5 pages, 4 figure

Quantification and prognostic relevance of angiogenic parameters in invasive cervical cancer.

Tumour stromal neovascularization was investigated in 114 invasive and 20 in situ carcinomas of the uterine cervix by staining representative sections with the specific endothelial marker anti CD31 (clone JC/70A, isotope IgG1). A digital image analyser was used to measure the immunoreactivity. The following parameters were determined in the 'hot spots': vessel counts, vessel perimeter and endothelial stained area (expressed per mm2). The results were correlated with clinical and histopathological data. There was no significant relationship between the histopathological findings (tumour histology, tumour differentiation, FIGO stage, presence of lymph node metastasis or lymphovascular space involvement) and the median vessel count. In a univariate analysis all angiogenesis parameters had prognostic value: a higher vascularity was associated with worse prognosis (P < 0.05). Multiple regression analysis showed that vascular permeation (P < 0.001) and the median vessel count (P = 0.005) were the most important prognostic indicators. In the future these criteria may be used for selection of patients for anti-angiogenesis therapy

A new generic open pit mine planning process with risk assessment ability

Conventionally, mining industry relies on a deterministic view, where a unique mine plan is determined based on a single resource model. A major shortfall of this approach is the inability to assess the risk caused by the well-known geological uncertainty, i.e. the in situ grade and tonnage variability of the mineral deposit. Despite some recent attempts in developing stochastic mine planning models which have demonstrated promising results, the industry still remains sceptical about this innovative idea. With respect to unbiased linear estimation, kriging is the most popular and reliable deterministic interpolation technique for resource estimation and it appears to remain its popularity in the near future. This paper presents a new systematic framework to quantify the risk of kriging-based mining projects due to the geological uncertainties. Firstly, conditional simulation is implemented to generate a series of equally-probable orebody realisations and these realisations are then compared with the kriged resource model to analyse its geological uncertainty. Secondly, a production schedule over the life of mine is determined based on the kriged resource model. Finally, risk profiles of that production schedule, namely ore and waste tonnage production, blending grade and Net Present Value (NPV), are constructed using the orebody realisations. The proposed model was applied on a multi-element deposit and the result demonstrates that that the kriging-based mine plan is unlikely to meet the production targets. Especially, the kriging-based mine plan overestimated the expected NPV at a magnitude of 6.70% to 7.34% (135 M$to 151 M$). A new multivariate conditional simulation framework was also introduced in this paper to cope with the multivariate nature of the deposit. Although an iron ore deposit is used to prove the concepts, the method can easily be adapted to other kinds of mineral deposits, including surface coal mine

Microvessel quantification in primary colorectal carcinoma: an immunohistochemical study.

The vascularisation of human primary colorectal carcinomas was studied immunohistochemically using the endothelial cell markers CD31 and factor VIII-related antigen. Tumour sections were systematically scanned at a magnification of x 100 to find areas of intense neovascularisation. Microvessel counts within these vascular 'hotspots' were performed at magnification x 250. Regions in which tumour cords were surrounded by a collagen IV-positive basement membrane were compared with those in which this was absent and with normal mucosa. CD31 appeared to be a more sensitive marker for endothelial cells than factor VIII-related antigen (mean 185 +/- 59 and 120 +/- 38 microvessels mm-2). Within individual tumour sections microvessel counts in vascular hotspots with highest vessel density correlated significantly with microvessel counts in vascular hotspots with second highest vessel density (P < 0.01). Microvessel counts in tumour areas where collagen IV-positive basement membrane were absent exceeded those in areas where it was present (factor of 1.7) and those in normal mucosa (factor of 1.6). The differences in vessel density between individual tumours and the low variability in vessel density within individual tumours using this quantification technique allow us to investigate the prognostic value of vessel density in areas of intense neovascularisation in human primary colorectal carcinomas

In vitro production of bovine embryos derived from individual donors in the Corral® dish

Background: Since the identity of the embryo is of outmost importance during commercial in vitro embryo production, bovine oocytes and embryos have to be cultured strictly per donor. Due to the rather low yield of oocytes collected after ovum pick-up (OPU) per individual cow, oocyte maturation and embryo culture take place in small groups, which is often associated with inferior embryo development. The objective of this study was to improve embryonic development in small donor groups by using the Corral (R) dish. This commercial dish is designed for human embryo production. It contains two central wells that are divided into quadrants by a semi-permeable wall. In human embryo culture, one embryo is placed per quadrant, allowing individual follow-up while embryos are exposed to a common medium. In our study, small groups of oocytes and subsequently embryos of different bovine donors were placed in the Corral (R) dish, each donor group in a separate quadrant. Results: In two experiments, the Corral (R) dish was evaluated during in vitro maturation (IVM) and/or in vitro culture (IVC) by grouping oocytes and embryos of individual bovine donors per quadrant. At day 7, a significantly higher blastocyst rate was noted in the Corral (R) dish used during IVM and IVC than when only used during IVM (12.9% +/- 2.10 versus 22.8% +/- 2.67) (P < 0.05). However, no significant differences in blastocyst yield were observed anymore between treatment groups at day 8 post insemination. Conclusions: In the present study, the Corral (R) dish was used for in vitro embryo production (IVP) in cattle; allowing to allocate oocytes and/or embryos per donor. As fresh embryo transfers on day 7 have higher pregnancy outcomes, the Corral (R) dish offers an added value for commercial OPU/IVP, since a higher blastocyst development at day 7 is obtained when the Corral (R) dish is used during IVM and IVC