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5. The assessment of organic matter Young's Modulus Distribution with depositional environment and maturity

Author

Fender, T.D., Van Der Land, C., Rouainia, M., Graham, S.P., Jones, D.M., Vane, C.H., Wagner, T., Fender, T.D., Van Der Land, C., Rouainia, M., Graham, S.P., Jones, D.M., Vane, C.H., and Wagner, T.

Abstract

Quantification of risk to seal integrity in CCS, or gas extraction from hydraulic fracturing, is directly affected by the accessibility of organic pores within organic rich mudrocks. Knowledge of the host organic matter's mechanical properties, which are influenced by depositional environment and thermal maturity, are required to reduce operational risk. In this study we address the effect of both depositional environment and maturity on organic matter Young's modulus by means of Atomic Force Microscopy Quantitative ImagingTM, which is a nondestructive technique capable of nanomechanical measurements. Shales from varying marine depositional environments covering kerogen Types II (Barnett), IIS (Tarfaya), and II/III (Eagle Ford/ Bowland) are analyzed to capture variance in organic matter. The findings show organic matter has a Young's modulus ranging between 0.1 and 24 GPa. These marine shales have a bimodal distribution of Young's modulus to some degree, with peaks at between 3–10 and 19–24 GPa. These shales exhibit a trend with maturity, whereby Young's modulus values of <10 GPa are dominant in immature Tarfaya shale, becoming similar to the proportion of values above 15 GPa within the oil window, before the stiffer values dominate into the gas window. These peaks most likely represent soft heterogeneous aliphatic rich kerogen and stiff ordered aromatic rich kerogen, evidenced by the increase in the stiffer component with maturity and correlated with 13C NMR spectrocopy. These findings enable increased realism in microscale geomechanical fracture tip propagation models and may allow direct comparison between Young's modulus and Rock‐Eval parameters. Plain Language Summary Gas recovery from hydraulic fracturing and validating the top‐seal integrity for carbon capture and storage require knowledge of key mechanical properties of the associate mudrock. One key property is elasticity (Young's modulus), which is relatively well constrained for each component of a shale

Published
2020

7. The bovine CD1D gene has an unusual gene structure and is expressed but cannot present α-galactosylceramide with a C26 fatty acid

Author

Nguyen, T.K.A., Koets, A.P., Vordermeier, M., Jervis, P.J., Cox, L.R., Graham, S.P., Santema, W.J., Moody, D.B., van Calenbergh, S., Zajonc, D.M., Besra, G.S., van Rhijn, I., Strategic Infection Biology, Dep Infectieziekten Immunologie, and Dep Gezondheidszorg Landbouwhuisdieren

Subjects
Signal peptide, endocrine system, Synthetic antigen, Immunology, CD1, Gene Expression, Galactosylceramides, chemical and pharmacologic phenomena, Ligands, Body Temperature, Cell Line, Mice, Animals, Humans, Immunology and Allergy, Gene, Original Research, chemistry.chemical_classification, Genetics, Base Sequence, biology, Fatty Acids, Fatty acid, hemic and immune systems, General Medicine, Natural killer T cell, Cell biology, carbohydrates (lipids), chemistry, Cell culture, CD1D, biology.protein, Cytokines, Natural Killer T-Cells, Cattle, lipids (amino acids, peptides, and proteins), Antigens, CD1d
Abstract

Although CD1d and NKT cells have been proposed to have highly conserved functions in mammals, data on functions of CD1d and NKT cells in species other than humans and rodents are lacking. Upon stimulation with the CD1d-presented synthetic antigen α-galactosylceramide, human and rodent type I invariant NKT cells release large amounts of cytokines. The two bovine CD1D (boCD1D) genes have structural features that suggest that they cannot be translated into functional proteins expressed on the cell surface. Here we provide evidence that despite an intron–exon structure and signal peptide that are different from all other known CD1 genes, boCD1D can be translated into a protein that is expressed on the cell surface. However, in vivo treatment of cattle (Bos taurus) with 0.1, 1, or 10 µg kg–1 of the most commonly used α-galactosylceramide, which has a C26 fatty acid, did not lead to an increase in body temperature and serum cytokine levels of the animals. This lack of reactivity is not due to a complete inability of boCD1d to present glycosphingolipids because α-galactosylceramide variants with shorter fatty acids could be presented by boCD1d to human NKT cells in vitro. This suggests that the natural ligands of boCD1d are smaller lipids.

Published
2012
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9. Differential lung NK cell responses in avian influenza virus infected chickens correlate with pathogenicity

Author

Jansen, C.A., de Geus, E.D., van Haarlem, D.A., van de Haar, P.M., Löndt, B.Z, Graham, S.P., Göbel, T.W., van Eden, W., Brookes, S.M., Vervelde, L., Strategic Infection Biology, Dep Infectieziekten Immunologie, LS Immunologie, Strategic Infection Biology, Dep Infectieziekten Immunologie, and LS Immunologie

Subjects
viruses, Cell, Biology, medicine.disease_cause, Article, Virus, Microbiology, 03 medical and health sciences, 0302 clinical medicine, Immunity, medicine, Animals, Life Science, Viral rna, 030304 developmental biology, 0303 health sciences, Multidisciplinary, Avian influenza virus, Lung, virus diseases, Orthomyxoviridae, Pathogenicity, Virology, Influenza A virus subtype H5N1, 3. Good health, Killer Cells, Natural, medicine.anatomical_structure, Influenza in Birds, Chickens, 030215 immunology
Abstract

Infection of chickens with low pathogenicity avian influenza (LPAI) virus results in mild clinical signs while infection with highly pathogenic avian influenza (HPAI) viruses causes death of the birds within 36–48 hours. Since natural killer (NK) cells have been shown to play an important role in influenza-specific immunity, we hypothesise that NK cells are involved in this difference in pathogenicity. To investigate this, the role of chicken NK-cells in LPAI virus infection was studied. Next activation of lung NK cells upon HPAI virus infection was analysed. Infection with a H9N2 LPAI virus resulted in the presence of viral RNA in the lungs which coincided with enhanced activation of lung NK cells. The presence of H5N1 viruses, measured by detection of viral RNA, did not induce activation of lung NK cells. This suggests that decreased NK-cell activation may be one of the mechanisms associated with the enhanced pathogenicity of H5N1 viruses.

Published
2013
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12. Differential lung NK cell responses in avian influenza virus infected chickens correlate with pathogenicity

Author

Strategic Infection Biology, Dep Infectieziekten Immunologie, LS Immunologie, Jansen, C.A., de Geus, E.D., van Haarlem, D.A., van de Haar, P.M., Löndt, B.Z, Graham, S.P., Göbel, T.W., van Eden, W., Brookes, S.M., Vervelde, L., Strategic Infection Biology, Dep Infectieziekten Immunologie, LS Immunologie, Jansen, C.A., de Geus, E.D., van Haarlem, D.A., van de Haar, P.M., Löndt, B.Z, Graham, S.P., Göbel, T.W., van Eden, W., Brookes, S.M., and Vervelde, L.

Published
2013

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