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56. Exome resequencing reveals ADCK4 mutations as novel causes of steroid-resistant nephrotic syndrome

Author

Ashraf, S., Gee, H. Y., Woerner, S., Xie, L. X., Vega Warner, V., Lovric, S., Fang, H., Song, X., Cattran, D., Avila Casado, C., Paterson, A. D., Nitschke, P., Cochat, C. Bole F. e. y. s. o. t. P., Esteve Rudd, J., Haberberger, B., Allen, S. J., Zhou, W., Airik, R., Otto, E. A., Barua, M., Al Hamed, M. H., Kari, J. A., Evans, J., Bierzynska, A., Saleem, M. A., Bockenhauer, D., Kleta, R., El Desoky, S., Hacihamdioglu, D. O., Gok, F., Wiggins, R. C., Lifton, M. C. h. o. i. R. P., Levy, S., Han, Z., Salviati, Leonardo, Prokisch, H., Williams, D. S., Pollak, M., Clarke, C. F., Pei, Y., Antignac, C., and Hildebrandt, F.

Published
2013

58. A feasibility study for a survey of migrants

Author

Smith, P, Cleary, A, Jones, M, Johnston, S, Bremner, P, Brown, JJ, and Wiggins, R

Abstract

Overview. The Analysis, Reserach and knowledge management Directorate (ARK) in the UK Border Agency commissioned Ipsos MORI and the Institute of Education to undertake a feasibility study for a large-scale face-to-face survey of migrants in the UK. The purpose of the feasibility study was to inform the design of a survey of migrants, looking at how to design and interview statistically robust sample and the appropriate questions to adopt such a survey. The feasibility study involved: 1. workshops with the UK Border Agency and other stakeholders to identify survey requirements; 2. the development of a definition of 'migrant' for use in the survey 3. the development of a sample design; 4. testing fieldwork recruitment and data collection methods to be used; and 5. the development of a questionnaire, including cognitive testing in several languages This report focuses on the sampling and field methods aspects of the feasibility study. A separate technical report provides details on other issues, including question development. To inform the development of the survey methodology and the survey questionnaire discussion groups and depth interviews were undertaken with representatives of economic migrant communities and individuals working with refugees and asylum seekers in England and Scotland. Key issues surrounding survey objectives, terminology, and field methods were identified. A useable survey population definition was developed after stakeholder consultaion such that, for the purpose of this study: 'A migrant is defined as someone who arrived in the UK in 1990 or later, who was a non-UK national on entry, whose usual place of residence prior to entry was not in the UK, and who has lived in the country for at least three months (one month if an asylum seeker or refugee).' It was concluded that different types of migrants will require different sampling and screening methods. Asylum sekers could be sampled directly from administrative records but other migrant types would have to be screened in the field. Small area estimation methods were successfully used to identify areas in which migrants are more heavily concentrated in order to inform the sample design. A number of field screening methods were investigated and field tested. Despite testing some innovative methods, traditional screening methods were found to still have an important role to play. It was concluded that non-asylum-seeker migrants should be screened through a combination of traditional screening methods for areas of higher migrant concentration and an adapted form of the Waksberg method (a two-stage method originally developed to minimise the number of calls made to ineligible numbers in telephone surveys) for areas of lower migrant concentration. An overall approach to a sample design was outlined and illustrative designs were presented applicable potentially to 6,000 interviews in England and 3,000 in Scotland. It was concluded that the survey should aim for 80 per cent coverage of the migrant population and that fieldwork effort should be disproportionately concentrated in areas of higher migrant concentration. The overall conclusion from the work was that a high quality survey of migrants would be feasible although a detailed design would need to take into consideration the level of funding available and how competing design requiremenets should be prioritised. In carrying out any such survey a large-scale dress rehearsal survey should be conducted before resources are fully committed in order to confirm the assumptions underlying the sample design and to field test the questionnaire and field translation/interpreting procedures.

Published
2011

66. COQ6 mutations in human patients produce nephrotic syndrome with sensorineural deafness

Author

Heeringa, S F, Chernin, G, Chaki, M, Zhou, W, Sloan, A J, Ji, Z, Xie, L X, Salviati, L, Hurd, T W, Vega-Warner, V, Killen, P D, Raphael, Y, Ashraf, S, Ovunc, B, Schoeb, D S, McLaughlin, H M, Airik, R, Vlangos, C N, Gbadegesin, R, Hinkes, B, Saisawat, P, Trevisson, E, Doimo, M, Casarin, A, Pertegato, V, Giorgi, G, Prokisch, H, Rötig, A, Nürnberg, G, Becker, C, Wang, S, Ozaltin, F, Topaloglu, R, Bakkaloglu, A, Bakkaloglu, S A, Müller, D, Beissert, A, Mir, S, Berdeli, A, Varpizen, S, Zenker, M, Matejas, V, Santos-Ocaña, C, Navas, P, Kusakabe, T, Kispert, A, Akman, S, Soliman, N A, Krick, S, Mundel, P, Reiser, J, Nürnberg, P, Clarke, C F, Wiggins, R C, Faul, C, Hildebrandt, F, Heeringa, S F, Chernin, G, Chaki, M, Zhou, W, Sloan, A J, Ji, Z, Xie, L X, Salviati, L, Hurd, T W, Vega-Warner, V, Killen, P D, Raphael, Y, Ashraf, S, Ovunc, B, Schoeb, D S, McLaughlin, H M, Airik, R, Vlangos, C N, Gbadegesin, R, Hinkes, B, Saisawat, P, Trevisson, E, Doimo, M, Casarin, A, Pertegato, V, Giorgi, G, Prokisch, H, Rötig, A, Nürnberg, G, Becker, C, Wang, S, Ozaltin, F, Topaloglu, R, Bakkaloglu, A, Bakkaloglu, S A, Müller, D, Beissert, A, Mir, S, Berdeli, A, Varpizen, S, Zenker, M, Matejas, V, Santos-Ocaña, C, Navas, P, Kusakabe, T, Kispert, A, Akman, S, Soliman, N A, Krick, S, Mundel, P, Reiser, J, Nürnberg, P, Clarke, C F, Wiggins, R C, Faul, C, and Hildebrandt, F

Abstract

Steroid-resistant nephrotic syndrome (SRNS) is a frequent cause of end-stage renal failure. Identification of single-gene causes of SRNS has generated some insights into its pathogenesis; however, additional genes and disease mechanisms remain obscure, and SRNS continues to be treatment refractory. Here we have identified 6 different mutations in coenzyme Q10 biosynthesis monooxygenase 6 (COQ6) in 13 individuals from 7 families by homozygosity mapping. Each mutation was linked to early-onset SRNS with sensorineural deafness. The deleterious effects of these human COQ6 mutations were validated by their lack of complementation in coq6-deficient yeast. Furthermore, knockdown of Coq6 in podocyte cell lines and coq6 in zebrafish embryos caused apoptosis that was partially reversed by coenzyme Q10 treatment. In rats, COQ6 was located within cell processes and the Golgi apparatus of renal glomerular podocytes and in stria vascularis cells of the inner ear, consistent with an oto-renal disease phenotype. These data suggest that coenzyme Q10-related forms of SRNS and hearing loss can be molecularly identified and potentially treated.

Published
2011

67. Individuals with mutations in XPNPEP3, which encodes a mitochondrial protein, develop a nephronophthisis-like nephropathy.

Author

O'Toole, J.F., Liu, Y., Davis, E.E., Westlake, C.J., Attanasio, M., Otto, E.A., Seelow, D., Nurnberg, G., Becker, C., Nuutinen, M., Karppa, M., Ignatius, J., Uusimaa, J., Pakanen, S., Jaakkola, E., Heuvel, L.P.W.J. van den, Fehrenbach, H., Wiggins, R., Goyal, M., Zhou, W., Wolf, M.T., Wise, E., Helou, J., Allen, S.J., Murga-Zamalloa, C.A., Ashraf, S., Chaki, M., Heeringa, S., Chernin, G., Hoskins, B.E., Chaib, H., Gleeson, J., Kusakabe, T., Suzuki, T., Isaac, R.E., Quarmby, L.M., Tennant, B., Fujioka, H., Tuominen, H., Hassinen, I., Lohi, H., Houten, J.L. van, Rotig, A., Sayer, J.A., Rolinski, B., Freisinger, P., Madhavan, S.M., Herzer, M., Madignier, F., Prokisch, H., Nurnberg, P., Jackson, P.K., Khanna, H., Katsanis, N., Hildebrandt, F., O'Toole, J.F., Liu, Y., Davis, E.E., Westlake, C.J., Attanasio, M., Otto, E.A., Seelow, D., Nurnberg, G., Becker, C., Nuutinen, M., Karppa, M., Ignatius, J., Uusimaa, J., Pakanen, S., Jaakkola, E., Heuvel, L.P.W.J. van den, Fehrenbach, H., Wiggins, R., Goyal, M., Zhou, W., Wolf, M.T., Wise, E., Helou, J., Allen, S.J., Murga-Zamalloa, C.A., Ashraf, S., Chaki, M., Heeringa, S., Chernin, G., Hoskins, B.E., Chaib, H., Gleeson, J., Kusakabe, T., Suzuki, T., Isaac, R.E., Quarmby, L.M., Tennant, B., Fujioka, H., Tuominen, H., Hassinen, I., Lohi, H., Houten, J.L. van, Rotig, A., Sayer, J.A., Rolinski, B., Freisinger, P., Madhavan, S.M., Herzer, M., Madignier, F., Prokisch, H., Nurnberg, P., Jackson, P.K., Khanna, H., Katsanis, N., and Hildebrandt, F.

Abstract

Contains fulltext : 88043.pdf (publisher's version ) (Closed access), The autosomal recessive kidney disease nephronophthisis (NPHP) constitutes the most frequent genetic cause of terminal renal failure in the first 3 decades of life. Ten causative genes (NPHP1-NPHP9 and NPHP11), whose products localize to the primary cilia-centrosome complex, support the unifying concept that cystic kidney diseases are "ciliopathies". Using genome-wide homozygosity mapping, we report here what we believe to be a new locus (NPHP-like 1 [NPHPL1]) for an NPHP-like nephropathy. In 2 families with an NPHP-like phenotype, we detected homozygous frameshift and splice-site mutations, respectively, in the X-prolyl aminopeptidase 3 (XPNPEP3) gene. In contrast to all known NPHP proteins, XPNPEP3 localizes to mitochondria of renal cells. However, in vivo analyses also revealed a likely cilia-related function; suppression of zebrafish xpnpep3 phenocopied the developmental phenotypes of ciliopathy morphants, and this effect was rescued by human XPNPEP3 that was devoid of a mitochondrial localization signal. Consistent with a role for XPNPEP3 in ciliary function, several ciliary cystogenic proteins were found to be XPNPEP3 substrates, for which resistance to N-terminal proline cleavage resulted in attenuated protein function in vivo in zebrafish. Our data highlight an emerging link between mitochondria and ciliary dysfunction, and suggest that further understanding the enzymatic activity and substrates of XPNPEP3 will illuminate novel cystogenic pathways.

Published
2010

68. Mental health and resilience at older ages : bouncing back after adversity in the British Household Panel Survey

Author

Netuveli, G., Wiggins, R. D., Montgomery, Scott M., Hildon, Z., Blane, D., Netuveli, G., Wiggins, R. D., Montgomery, Scott M., Hildon, Z., and Blane, D.

Abstract

Background: Resilience is having good outcomes despite adversity and risk and could be described in terms of preserving the same level of the outcome or rebounding back to that level after an initial set back. Using the latter definition, resilience as “bouncing back”, this paper aims (1) to identify those members of a panel survey who demonstrated resilience, and (2) to identify the characteristics of the resilient individuals and the predictors of their resilience. Methods: The study subjects were the 3581 participants in the British Household Panel Survey, selected from waves 1–14, who satisfied three requirements: exposure to an adversity; availability of consecutive General Health Questionnaire (GHQ)-12 scores; aged 50 or more years. The primary outcome variable was resilience, operationalised as a GHQ-12 score that increased after exposure to adversity and returned to its pre-exposure level in the next (after 1 year) wave of the survey. The adversities were: functional limitation; bereavement or marital separation; poverty. Results: The prevalence of resilience, as defined, was 14.5%. After adjusting for regression to the mean, the GHQ-12 score of the resilient dropped by a mean of 3.6 points in the post-adversity period. Women predominated among the resilient, with this gender difference stronger among older women than younger women. The resilient were more likely to have high social support than the non-resilient, but otherwise were not different socioeconomically. High social support pre-adversity and during adversity increased the likelihood of resilience by 40–60% compared with those with low social support. Conclusions: Resilience is relatively rare and favours older women. It is fostered by high levels of social support existing before exposure to adversity.

Published
2008
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69. Experimental models of CKD

Author

Kanlaya, R., primary, Sintiprungrat, K., additional, Thongboonkerd, V., additional, Torremade, N., additional, Bindels, R., additional, Hoenderop, J., additional, Fernandez, E., additional, Dusso, A., additional, Valdivielso, J. M., additional, Krueger, T., additional, Boor, P., additional, Schafer, C., additional, Westenfeld, R., additional, Brandenburg, V., additional, Schlieper, G., additional, Jahnen-Dechent, W., additional, Ketteler, M., additional, Jee, W., additional, Li, X., additional, Richards, B., additional, Floege, J., additional, Goncalves, J. G., additional, Canale, D., additional, de Braganca, A. C., additional, Shimizu, M. H. M., additional, Moyses, R. M. A., additional, Andrade, L., additional, Seguro, A. C., additional, Volpini, R. A., additional, Romoli, S., additional, Migliorini, A., additional, Anders, H.-J., additional, Eskova, O., additional, Neprintseva, N., additional, Tchebotareva, N., additional, Bobkova, I., additional, Kozlovskaya, L., additional, Simic, I., additional, Tabatabaeifar, M., additional, Wlodkowski, T., additional, Denc, H., additional, Mollet, G., additional, Antignac, C., additional, Schaefer, F., additional, Ekaterina, I. A., additional, Giardino, L., additional, Rastaldi, M. P., additional, Van den Heuvel, L., additional, Levtchenko, E., additional, Okina, C., additional, Okamoto, T., additional, Kamata, M., additional, Murano, J., additional, Kobayashi, K., additional, Takeuchi, K., additional, Kamata, F., additional, Sakai, T., additional, Naito, S., additional, Aoyama, T., additional, Sano, T., additional, Takeuchi, Y., additional, Kamata, K., additional, Thomasova, D., additional, Bruns, H. A., additional, Liapis, H., additional, Iwashita, T., additional, Hasegawa, H., additional, Takayanagi, K., additional, Shimizu, T., additional, Asakura, J., additional, Okazaki, S., additional, Kogure, Y., additional, Hatano, M., additional, Hara, H., additional, Inamura, M., additional, Iwanaga, M., additional, Mitani, T., additional, Mitarai, T., additional, Savin, V. J., additional, Sharma, M., additional, Wei, C., additional, Reiser, J., additional, McCarthy, E. T., additional, Sharma, R., additional, Gauchat, J.-F., additional, Eneman, B., additional, Freson, K., additional, Van Geet, C., additional, Choi, D. E., additional, Jeong, J. Y., additional, Chang, Y. K., additional, Na, K.-R., additional, Lee, K. W., additional, Shin, Y. T., additional, Ni, H.-F., additional, Chen, J.-F., additional, Zhang, M.-H., additional, Pan, M.-M., additional, Liu, B.-C., additional, Kim, S. S., additional, Suzuki, T., additional, Iyoda, M., additional, Matsumoto, K., additional, Shindo-Hirai, Y., additional, Kuno, Y., additional, Wada, Y., additional, Yamamoto, Y., additional, Shibata, T., additional, Akizawa, T., additional, Munoz-Felix, J. M., additional, Lopez-Novoa, J. M., additional, Martinez-Salgado, C., additional, Ehling, J., additional, Babickova, J., additional, Gremse, F., additional, Kiessling, F., additional, Lammers, T., additional, Lech, M., additional, Gunthner, R., additional, Lorenz, G., additional, Ryu, M., additional, Grobmayr, R., additional, Susanti, H., additional, Kobayashi, K. S., additional, Flavell, R. A., additional, Rayego-Mateos, S., additional, Morgado, J., additional, Sanz, A. B., additional, Eguchi, S., additional, Pato, J., additional, Keri, G., additional, Egido, J., additional, Ortiz, A., additional, Ruiz-Ortega, M., additional, Leduc, M., additional, Geerts, L., additional, Grouix, B., additional, Sarra-Bournet, F., additional, Felton, A., additional, Gervais, L., additional, Abbott, S., additional, Duceppe, J.-S., additional, Zacharie, B., additional, Penney, C., additional, Laurin, P., additional, Gagnon, L., additional, Detsika, M. G., additional, Duann, P., additional, Lianos, E. A., additional, Leong, K. I., additional, Chiang, C.-K., additional, Yang, C.-C., additional, Wu, C.-T., additional, Chen, L.-P., additional, Hung, K.-Y., additional, Liu, S.-H., additional, Carvalho, F. F., additional, Teixeira, V. P., additional, Almeida, W. S., additional, Schor, N., additional, Small, D. M., additional, Bennett, N. C., additional, Coombes, J., additional, Johnson, D. W., additional, Gobe, G. C., additional, Montero, N., additional, Prada, A., additional, Riera, M., additional, Orfila, M., additional, Pascual, J., additional, Rodriguez, E., additional, Barrios, C., additional, Kokeny, G., additional, Fazekas, K., additional, Rosivall, L., additional, Mozes, M. M., additional, Hornigold, N., additional, Hughes, J., additional, Mooney, A., additional, Benardeau, A., additional, Riboulet, W., additional, Vandjour, A., additional, Jacobsen, B., additional, Apfel, C., additional, Conde-Knape, K., additional, Bienvenu, J.-F., additional, Tanaka, T., additional, Yamaguchi, J., additional, Nangaku, M., additional, Niwa, T., additional, Bolati, D., additional, Shimizu, H., additional, Yisireyili, M., additional, Nishijima, F., additional, Brocca, A., additional, Virzi, G., additional, de Cal, M., additional, Ronco, C., additional, Priante, G., additional, Musacchio, E., additional, Valvason, C., additional, Sartori, L., additional, Piccoli, A., additional, Baggio, B., additional, Perkuhn, M., additional, Weibrecht, M., additional, Zok, S., additional, Martin, I. V., additional, Schoth, F., additional, Ostendorf, T., additional, Kuhl, C., additional, Karabaeva, A., additional, Essaian, A., additional, Beresneva, O., additional, Parastaeva, M., additional, Kayukov, I., additional, Smirnov, A., additional, Audzeyenka, I., additional, Kasztan, M., additional, Piwkowska, A., additional, Rogacka, D., additional, Angielski, S., additional, Jankowski, M., additional, Bockmeyer, C. L., additional, Kokowicz, K., additional, Agustian, P. A., additional, Zell, S., additional, Wittig, J., additional, Becker, J. U., additional, Nishizono, R., additional, Venkatareddy, M. P., additional, Chowdhury, M. A., additional, Wang, S. Q., additional, Fukuda, A., additional, Wickman, L. T., additional, Yang, Y., additional, Wiggins, R. C., additional, Fazio, M. R., additional, Donato, V., additional, Lucisano, S., additional, Cernaro, V., additional, Lupica, R., additional, Trimboli, D., additional, Montalto, G., additional, Aloisi, C., additional, Mazzeo, A. T., additional, Buemi, M., additional, Gawrys, O., additional, Olszynski, K. H., additional, Kuczeriszka, M., additional, Gawarecka, K., additional, Swiezewska, E., additional, Chmielewski, M., additional, Masnyk, M., additional, Rafalowska, J., additional, Kompanowska-Jezierska, E., additional, Lee, W.-C., additional, Chau, Y.-Y., additional, Lee, L.-C., additional, Chiu, C.-H., additional, Lee, C.-T., additional, Chen, J.-B., additional, Kim, W.-K., additional, and Shin, S. J., additional

Published
2013
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71. The Effect of Cortex/Medulla Proportions on Molecular Diagnoses in Kidney Transplant Biopsies: Rejection and Injury Can Be Assessed in Medulla

Author

Madill‐Thomsen, K. S., Wiggins, R. C., Eskandary, F., Böhmig, G. A., and Halloran, P. F.

Abstract

Histologic assessment of kidney transplant biopsies relies on cortex rather than medulla, but for microarray studies, the proportion cortex in a biopsy is typically unknown and could affect the molecular readings. The present study aimed to develop a molecular estimate of proportion cortex in biopsies and examine its effect on molecular diagnoses. Microarrays from 26 kidney transplant biopsies divided into cortex and medulla components and processed separately showed that many of the most significant differences were in glomerular genes (e.g. NPHS2, NPHS1, CLIC5, PTPRO,PLA2R1, PLCE1, PODXL, and REN). Using NPHS2(podocin) to estimate proportion cortex, we examined whether proportion cortex influenced molecular assessment in the molecular microscope diagnostic system. In 1190 unselected kidney transplant indication biopsies (Clinicaltrials.govNCT01299168), only 11% had <50% cortex. Molecular scores for antibody‐mediated rejection, T cell–mediated rejection, and injury were independent of proportion cortex. Rejection was diagnosed in many biopsies that were mostly or all medulla. Agreement in molecular diagnoses in paired cortex/medulla samples (23/26) was similar to biological replicates (32/37). We conclude that NPHS2expression can estimate proportion cortex; that proportion cortex has little influence on molecular diagnosis of rejection; and that, although histology cannot assess medulla, rejection does occur in medulla as well as cortex. Using podocin expression to estimate proportion cortex in renal transplant biopsies reveals that rejection does occur in the medulla, and the proportion of medulla has little influence on the molecular microscope diagnosis of rejection.

Published
2017
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78. EXPERT ddx Head and Neck

Author

Harnsberger, H.R., primary, Glastonbury, C.M., additional, Michel, M.A., additional, Koch, B.L., additional, Phillips, C.D., additional, Mosier, K., additional, Hudgins, P., additional, Wiggins, R., additional, Davidson, H.C., additional, and Curé, J., additional

Published
2009
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83. Mutations in PLCE1 are a major cause of isolated diffuse mesangial sclerosis (IDMS)

Author

Gbadegesin, R., primary, Hinkes, B. G., additional, Hoskins, B. E., additional, Vlangos, C. N., additional, Heeringa, S. F., additional, Liu, J., additional, Loirat, C., additional, Ozaltin, F., additional, Hashmi, S., additional, Ulmer, F., additional, Cleper, R., additional, Ettenger, R., additional, Antignac, C., additional, Wiggins, R. C., additional, Zenker, M., additional, and Hildebrandt, F., additional

Published
2007
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84. The general linear inverse problem - Implication of surface waves and free oscillations for earth structure.

Author

Wiggins, R. A

Subjects
Geophysics
Abstract

The discrete general linear inverse problem reduces to a set of m equations in n unknowns. There is generally no unique solution, but we can find k linear combinations of parameters for which restraints are determined. The parameter combinations are given by the eigenvectors of the coefficient matrix. The number k is determined by the ratio of the standard deviations of the observations to the allowable standard deviations in the resulting solution. Various linear combinations of the eigenvectors can be used to determine parameter resolution and information distribution among the observations. Thus we can determine where information comes from among the observations and exactly how it constraints the set of possible models. The application of such analyses to surface-wave and free-oscillation observations indicates that (1) phase, group, and amplitude observations for any particular mode provide basically the same type of information about the model; (2) observations of overtones can enhance the resolution considerably; and (3) the degree of resolution has generally been overestimated for many model determinations made from surface waves.

Published
1972

85. Passive seismic experiment

Author

Dorman, J, Ewing, M, Kovach, R, Latham, G. V, Nakamura, Y, Press, F, Sutton, G, Toksoz, N, and Wiggins, R

Subjects
Geophysics
Abstract

Apollo 12 passive seismometer design and signal interpretation

Published
1970

86. Apollo 11 passive seismic experiment

Author

Dorman, J, Duennebier, F, Ewing, M, Latham, G. V, Nakamura, Y, Press, F, Sutton, G, Toksoz, N, and Wiggins, R

Subjects
Space Sciences
Abstract

Apollo 11 passive seismic experiment package, discussing design, performance and various received signals

Published
1970

89. Range of earth structure nonuniqueness implied by body wave observations.

Author

Wiggins, R. A, Mcmechan, G. A, and Toksoz, M. N

Subjects
Geophysics
Abstract

The Herglotz-Wiechert integral for the direct inversion of ray parameter versus distance curves can be manipulated to find the envelope of all possible models consistent with geometrical body wave observations (travel time and ray parameter versus distance). Such an extremal inversion approach has been used to find the uncertainty bounds for the velocity structure in the mantle and core. It is found, for example, that there is an uncertainty of plus or minus 40 km in the radius of the inner core boundary, plus or minus 18 km at the core-mantle boundary, and plus or minus 35 km at the 435-km transition zone. The velocity uncertainty is about plus or minus 0.08 km/sec for P and S waves in the lower mantle and about plus or minus 0.20 km/sec in the core. Experiments with various combinations of ray types in the core indicate that rather crude observations of SKKS-SKS travel times confine the range of possible models far more dramatically than do the most precise estimates of PmKP travel times. Comparisons of results from extremal inversion and linearized perturbation inversions indicate that body wave behavior is too strongly nonlinear for linearized schemes to be effective for predicting uncertainty.

Published
1973

90. Monte Carlo inversion of seismic data

Author

Wiggins, R. A

Subjects
Mathematics
Abstract

The analytic solution to the linear inverse problem provides estimates of the uncertainty of the solution in terms of standard deviations of corrections to a particular solution, resolution of parameter adjustments, and information distribution among the observations. It is shown that Monte Carlo inversion, when properly executed, can provide all the same kinds of information for nonlinear problems. Proper execution requires a relatively uniform sampling of all possible models. The expense of performing Monte Carlo inversion generally requires strategies to improve the probability of finding passing models. Such strategies can lead to a very strong bias in the distribution of models examined unless great care is taken in their application.

Published
1972

93. 2028

Author

Miller, D., primary, Wiggins, R., additional, Wharram, B., additional, Goyal, M., additional, Dou, C., additional, and Williams, A., additional

Published
2006
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