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Accounting for the noise is a fundamental step in probabilistic inversion approaches as well as a challenge for the practitioners. To investigate a pragmatic approach for noise description in probabilistic seismic inversion, we used a probabilistic sampling-based inversion method to invert seismic data associated with a hard carbonate reservoir in southwest Iran to porosity. We assumed eight different scenarios for the bandwidth and the magnitude of the noise. The posterior statistics assessment shows that ignoring the correlation of the noise samples in the noise covariance matrix generates unrealistic features in porosity realisations. Furthermore, underestimating the noise magnitude leads to overfitting the data and generates a biased model with too little uncertainty. These issues are resolved considerably when the noise bandwidth is considered in the inversion setup. This indicates the tangible effect of the noise bandwidth on the statistics of the posterior realisations. Our analyses showed that constructing the noise covariance matrix using extracted seismic wavelet is a practical solution. Our tests also show that the error propagated to the posterior realisations by using imperfect wavelet frequency spectrum in construction of the noise covariance matrix is insignificant.

Mitochondria (MT), the major site of cellular energy production, are under dual genetic control by 37 mitochondrial DNA (mtDNA) genes and numerous nuclear genes (MT-nDNA). In the CHARGEmtDNA+ Consortium, we studied genetic associations of mtDNA and MT-nDNA associations with body mass index (BMI), waist-hip-ratio (WHR), glucose, insulin, HOMA-B, HOMA-IR, and HbA1c. This 45-cohort collaboration comprised 70,775 (insulin) to 170,202 (BMI) pan-ancestry individuals. Validation and imputation of mtDNA variants was followed by single-variant and gene-based association testing. We report two significant common variants, one in MT-ATP6 associated (p ≤ 5E−04) with WHR and one in the D-loop with glucose. Five rare variants in MT-ATP6, MT-ND5, and MT-ND6 associated with BMI, WHR, or insulin. Gene-based meta-analysis identified MT-ND3 associated with BMI (p ≤ 1E−03). We considered 2,282 MT-nDNA candidate gene associations compiled from online summary results for our traits (20 unique studies with 31 dataset consortia's genome-wide associations [GWASs]). Of these, 109 genes associated (p ≤ 1E−06) with at least 1 of our 7 traits. We assessed regulatory features of variants in the 109 genes, cis- and trans-gene expression regulation, and performed enrichment and protein-protein interactions analyses. Of the identified mtDNA and MT-nDNA genes, 79 associated with adipose measures, 49 with glucose/insulin, 13 with risk for type 2 diabetes, and 18 with cardiovascular disease, indicating for pleiotropic effects with health implications. Additionally, 21 genes related to cholesterol, suggesting additional important roles for the genes identified. Our results suggest that mtDNA and MT-nDNA genes and variants reported make important contributions to glucose and insulin metabolism, adipocyte regulation, diabetes, and cardiovascular disease.

Introduction: In 2007, the Cancer Disease Hospital (CDH) was opened as the national referral center for patients diagnosed with cancer in Zambia. Since inception of the CDH, there has been no systematic analysis of the disease burden and implication on healthcare delivery with regards to pancreatic cancer. There are limited studies describing patterns of pancreatic cancer in a native African population. Data suggest African-Americans have a higher incidence and poorer prognosis of pancreatic cancer than non-African Americans.Objective: Our aim is to describe the demographic features (age, gender) of pancreatic cancer using the Cancer Disease Hospital (CDH) data base in a native African population and compare with the African-American cohort using the Surveillance, Epidemiology End Results (SEER) Program database.Methods: This was a retrospective study of patients diagnosed with pancreatic cancer at the CDH in Zambia, Southern Africa between 2007 and 2014. We entered the term “pancreatic cancer” into the CDH database, extracted patient medical records numbers, and manually located the records for review. From each chart we extracted: age, gender, geographic origin, ethnicity, clinical features at presentations, location of tumor, stage at diagnosis and treatment. Data collection tool and master code sheet created a priori were used. Data was analyzed using statistical analysis software (SAS). Descriptive statistics including means, medians as well as frequency distributions and crosstabulations were used. SEER database was used to compare subjects between Zambia and USA. Groups were compared using Chi-square tests and Wilcoxon Signed Rank test. Ap-value less than 0.05 was used as the level of significance.Results: Thirty-eight charts were identified in the CDH dataset, of which 27 were included in final analysis and 11 excluded (5 non-pancreatic cancer diagnosis, 6 not manually located). The mean age of diagnosis was 55.7 years in the native African population, compared to 66.7 years for the African-Americans in the SEER database, p < 0.0001. There were 63.0% males (CDH) compared to 48.1% (SEER), p=0.121. Further review of the CDH database revealed that the most common presenting symptom was abdominal pain (52.6%), mode of diagnosis surgical (83%, missing 3), histopathology adenocarcinoma (86%, missing 6), location head of pancreas (83%, missing 9) and stage 4 at diagnosis (100%, missing 3).Conclusion: Pancreatic cancer occurs at a younger age in Zambians when compared to the African American, USApopulation. There is no statistically significant difference in sex presentation between Zambian and USAblack population.