| 1. |
- Abrahamsen, Petter, et al.
(author)
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Estimation of Gross Rock Volume of Filled Geological Structures With Uncertainty Measures
- 2000
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In: SPE Reservoir Evaluation & Engineering. ; 3:4
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Journal article (peer-reviewed)abstract
- The gross rock volume of a filled structure is uncertain because of uncertainty in the determination of caprock depth and the uncertainty in depth to the hydrocarbon contact determined by the spill point of the caprock. Ignoring this uncertainty might lead to biased volume estimates. This paper reports two procedures to assist with assessing this uncertainty to obtain better estimates. The first is to use conditional simulation techniques to generate realizations of the depth to the caprock. The second procedure is a new fast algorithm that determines the location of the spill point and trapped area of each caprock realization. Taken together, the two procedures determine the thickness and lateral extension of each reservoir realization. Finally, gross rock volume for each realization can be calculated and the volumetric uncertainty can be quantified in terms of expectation, histograms, percentiles, etc., for the whole set of realizations. A synthetic example and an example from the North Sea illustrate the use of these procedures. A method for including knowledge of the spill-point depth for improving depth maps is also presented.
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| 2. |
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| 3. |
- Benson, Mikael, 1954, et al.
(author)
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DNA microarray analysis of transforming growth factor-β and related transcripts in nasal biopsies from patients with allergic rhinitis
- 2002
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In: Cytokine. ; 18:1, s. 20-25
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Journal article (peer-reviewed)abstract
- Decreased activity of anti-inflammatory cytokines like transforming growth factor (TGF)-β may contribute to allergic inflammation. In vivo effects of TGF-β-effects are difficult to infer from local concentrations, since TGF-β-effects depend on a complex system of regulatory proteins and receptors. Instead the effects of TGF-β might be inferred by examining TGF-β-inducible transcripts. In this study DNA microarrays were used to examine local expression of TGF-β, TGF-β-regulatory and -inducible transcripts in nasal biopsies from patients with symptomatic allergic rhinitis and healthy controls. In addition, nasal fluids were analysed with cytological and immunological methods. Nasal fluid eosinophils, albumin, eosinophil granulae proteins and IgE, but not TGF-β, were higher in patients than in controls. DNA microarray analysis of nasal mucosa showed expression of transcripts encoding TGF-β, TGF-β-regulatory proteins and -receptors at variable levels in patients and controls. By comparison, analysis of 28 TGF-β-inducible transcripts indicated that 23 of these had lower measurement values in patients than in controls, while one was higher, and the remaining four were absent in both patients and controls. In summary, TGF-β and a complex system of regulatory genes and receptors are expressed in the nasal mucosa. Low expression of TGF-β-inducible transcripts may indicate decreased TGF-β activity in allergic rhinitis. DNA microarray analysis may be a way to study cytokine effects in vivo.
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| 4. |
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| 5. |
- Dobosz, M, et al.
(author)
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FINEX, FAMILIAS: two different approaches for the analysis of defective paternity cases
- 2004
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In: International Congress Series. ; 1261, s. 65-66
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Journal article (peer-reviewed)abstract
- We provide an overview of the main features of two computer programs enabling to calculate Bayesian probabilities in defective paternity cases: FINEX and FAMILIAS. These packages turn out very useful when computation complexities exceed the ordinary pencil-and-paper approach powers. FAMILIAS is especially suited for all cases in which there is a basic uncertainty on the most likely pedigree. FINEX is an Expert System-based program enabling to tackle very complex cases with plenty of data.
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| 6. |
- Egeland, Thore, et al.
(author)
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Beyond traditional paternity and identification cases: Selecting the most probable pedigree
- 2000
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In: Forensic Science International. ; 110:1, s. 47-59
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Journal article (peer-reviewed)abstract
- The paper extends on the traditional methodology used to quantify DNA evidence in paternity or identificationcases. By extending we imply that there are more than two alternatives to choose between. In a standard paternitycase the two competing explanations H1: “John Doe is the father of the child” and H2: “A random man is the father of the child”, are typically considered. A paternity index of 100 000 implies that the data is 100 000 more likely assuming hypothesis H1 rather than H2. If H2 is replaced by “A brother of John Doe is the father”, the LR may change dramatically. The main topic of this paper is to determine the most probable pedigree given a certain set of data including DNA profiles. In the previous example this corresponds to determining the most likely relation between John Doe and the child. Based on DNA obtained from victims of a fire, bodies found in an ancient grave or from individuals seeking to confirm their anticipated family relations, we would like to determine the most probable pedigree. The approach we present provides the possibility to combine non-DNA evidence, say age of individuals, and DNA profiles. The program familias, obtainable as shareware from http://www.nr.no/familias, delivers the probabilities for the various family constellations. More precisely, the information (if any) prior to DNA is combined with the DNA-profiles in a Bayesian manner to deliver the posterior probabilities. We exemplify using the well published Romanov data where the accepted solution emerges among 4536 possibilities considered. Various other applications based on forensic case work are discussed. In addition we have simulated data to resemble an incest case. Since the true family relation is known in this case, we may evaluate the method.
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| 7. |
- Egeland, Thore, et al.
(author)
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Beyondtraditionalpaternity and identificationcases: Selecting the most probable pedigree
- 2002
-
In: Forensic Science International. ; 110:1, s. 47-59
-
Journal article (peer-reviewed)abstract
- The paper extends on the traditional methodology used to quantify DNA evidence in paternity or identificationcases. By extending we imply that there are more than two alternatives to choose between. In a standard paternitycase the two competing explanations H1: “John Doe is the father of the child” and H2: “A random man is the father of the child”, are typically considered. A paternity index of 100000 implies that the data is 100000 more likely assuming hypothesis H1 rather than H2. If H2 is replaced by “A brother of John Doe is the father”, the LR may change dramatically. The main topic of this paper is to determine the most probable pedigree given a certain set of data including DNA profiles. In the previous example this corresponds to determining the most likely relation between John Doe and the child. Based on DNA obtained from victims of a fire, bodies found in an ancient grave or from individuals seeking to confirm their anticipated family relations, we would like to determine the most probable pedigree. The approach we present provides the possibility to combine non-DNA evidence, say age of individuals, and DNA profiles. The program familias, obtainable as shareware from http://www.nr.no/familias, delivers the probabilities for the various family constellations. More precisely, the information (if any) prior to DNA is combined with the DNA-profiles in a Bayesian manner to deliver the posterior probabilities. We exemplify using the well published Romanov data where the accepted solution emerges among 4536 possibilities considered. Various other applications based on forensic case work are discussed. In addition we have simulated data to resemble an incest case. Since the true family relation is known in this case, we may evaluate the method.
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| 8. |
- Egeland, Thore, et al.
(author)
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Estimating the number of contributors to a DNA profile
- 2003
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In: International Journal of Legal Medicine. ; 117:5, s. 271-275
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Journal article (peer-reviewed)abstract
- The broad topic of this paper is the evaluation of DNA evidence in criminal cases. More specifically, we deal with mixture evidence which refers to cases where there are, or could be, several contributors to a biological stain based on, e.g., blood or semen. The present paper adresses DNA mixtures based on single nucleotide polymorphism (SNP) markers, i.e., diallelic markers. Based on STR analysis, it is in most cases easy to identify the presence of a mixture since three or four bands will show up with a high probability for at least one locus. Obviously, this will not be the case for diallelic markers and interpreting mixtures will be a great challenge. We address this problem by first approaching the more general problem of estimating the number of contributors to a stain. In addition we discuss how the markers should be selected and how many are required.
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| 9. |
- Egeland, Thore, et al.
(author)
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Statistical Genetics and Genetical Statistics: a Forensic Perspective
- 2002
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In: Scandinavian Journal of Statistics. ; 29:2, s. 297-307
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Journal article (peer-reviewed)abstract
- This review paper focuses on forensic aspects of the relation between statistics and genetics. Some of the scientific achievements of the Swedish psychiatrist and geneticist Erik Essen-Möller may be viewed in the above interdisciplinary context. In a number of situations the correct familial relation between a group of individuals is required. We discuss recent work done to relax some assumptions involved in the classical calculations in Essen-Möller (1938). Moreover, we extend the discussion to identification problems. In a given case there may be a large number of possible family constellations or pedigrees. A prior probability distribution is established. The posterior model accounts for the combinatorial complexities of the pedigrees, mutations, kinship, and uncertainty in allele frequencies. Examples are based on the shareware program FAMILIAS, see http://www.nr.no/familias. A main message of the present paper is that the Bayesian approach is a convenient framework to down-weight unreasonable (e.g. incestuous) pedigrees that may always appear likely if only DNA-measurements are used.
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| 10. |
- Holden, Lars, et al.
(author)
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Stochastic Structural Modeling
- 2003
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In: Mathematical Geology. ; 35:8, s. 899-914
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Journal article (peer-reviewed)abstract
- A consistent stochastic model for faults and horizons is described. The faults are represented as a parametric invertible deformation operator. The faults may truncate each other. The horizons are modeled as correlated Gaussian fields and are represented in a grid. Petrophysical variables may be modeled in a reservoir before faulting in order to describe the juxtaposition effect of the faulting. It is possible to condition the realization on petrophysics, horizons, and fault plane observations in wells in addition to seismic data. The transmissibility in the fault plane may also be included in the model. Four different methods to integrate the fault and horizon models in a common model is described. The method is illustrated on an example from a real petroleum field with 18 interpreted faults that are handled stochastically.
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