Permanent ground displacements due to earthquake faulting may induce large deformation and loading of a buried pipeline. In particular, a pipeline crossing a fault rupture emerging at the soil surface will be subject to a combination of bending and/or axial compression or tension depending on the form of the fault displacement, the dip angle and the direction of the pipe with respect to the fault. This complex combination of loadings may be sufficient to cause disruption to the pipeline supply or leakage of product and so has potential for large financial and/or environmental impact. In this paper, the response of buried flexible pipelines crossing reverse fault ruptures has been examined using centrifuge modelling. A reverse fault is actuated in the 20th-scale model at an initial fixed dip angle in the bedrock and the fault rupture is seen to propagate upwards through a layer of sand towards the soil surface. Pipelines were buried in the sand layer to typical embedment ratios and their response was monitored as the fault displacement increased monotonically. Primary data capture was by the use of image analysis: semi-cylindrical modelm pipelines were placed at the front-face of the model and digital images were captured during the loading event. This allowed pipeline deformation patterns and thereby bending moment distributions to be calculated throughout the fault rupture event. Results are presented to show the effect of pipeline diameter, stiffness and embedment depth on the performance of buried pipelines during reverse and normal faults. In particular, it is shown that additional embedment of the pipeline is detrimental to its performance due to the additional confining effect of the soil which changes the relative pipesoil stiffness.
Objectives: Chronic allograft nephropathy remains one of the main causes of late graft loss after kidney transplant owing to multifactorial development of kidney scarring. Chronic allograft nephropathy is characterised by an excess accumulation of extracellular matrix. A key system regulating extracellular matrix homeostasis are matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases. This study sought to determine if a change in the matrix metalloproteinases/tissue inhibitors of matrix metalloproteinases system contributes to chronic allograft nephropathy-associated progressive kidney scarring. Materials and Methods: Examination of sequential renal biopsies was done at implantation, acute rejection, and subsequent chronic allograft nephropathy. In situ localisation of matrix metalloproteinase activity was assessed with a high-resolution in situ zymography technique using gelatin and collagen 1 substrates. Matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases were localised using immunohistochemistry. Results: In situ zymography showed over a 50% reduction in matrix metalloproteinase activity against both collagen 1 and gelatin substrates in chronic allograft nephropathy biopsies. A similar loss of matrix metalloproteinase activity was seen in the glomerular and tubulointerstitial compartments.Immunoreactive matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases were observed intracellularly in mesangial and tubular epithelial cells. Matrix metalloproteinases-1, -2, -3, and -9 were significantly reduced in acute rejection and later in chronic allograft nephropathy. However, glomerular matrix metalloproteinases 1 and 9 and tubulointerstitial matrix metalloproteinase-2 were reduced at implantation. Tissue inhibitors of matrix metalloproteinase-2 and -3 were elevated from implantation onwards. We were unable to stain reproducibly for tissue inhibitors of matrix metalloproteinase-1. Conclusions: Kidney scarring underlying chronic allograft nephropathy is associated with a reduction in matrix metalloproteinases activity that may be due to reduced expression of matrix metalloproteinases -1, -2, -3, and -9, and upregulation of tissue inhibitors of matrix metalloproteinases -2 and -3. Some of these changes originate from implantation.
This paper describes how medical illustration has evolved to become increasingly important in undergraduate medical education, postgraduate medical education and continuing medical education, as new technologies have become available and new teaching methods have developed based on the emerging technologies. It also examines how the role of the medical illustrator has changed. The descriptor 'medical illustration' fails to reflect the changing face of the profession and it is suggested that a new title is required to convey better the evolving role of the profession.
The coastal plain of study area covered by sea water rich in fines derived from the clay lenses of the continental shelf by erosion process comprises three zones; eastern, middle and western. So, the high content of fines varies from 0.72 % to 74.08 with an average of 18%. The apparent specific gravity of topmost part of the sands one meter thick varies from 1.29 g/cm³ to 1.74 g/cm³ with an average of 1.59 g/cm³. The studied sediments are derived from river environment, due to the high content of clay and organic matter in the raw sands. The average percentage of sand fraction finer than 125 micron has an average value of 19.51 %, in which the total heavy fractions constitutes 92.78 % in average of its total amounts. The calculated total reserve of the economic heavy minerals reaches up to 578,760 tons separated from 2893.800 tons bulk sands. Its mineral constituents are; 182,850 tons magnetite, 329,130 tons ilmenite, 23,850 tons garnet, 14,310 tons leucoxene, 20,670 tons zircon, 6,996 tons rutile and 954 tons monazite. The radiometric measurements of the study area revealed that the western zone which occupies four square kilometers have high values of specific activity, absorbed and effective doses because of its high contents of monazite and radioactive zircon, while the eastern and middle zones each occupy three square kilometers posses a moderate to low values of these activities respectively. Therefore, the the western zone is not recommended as building materials because of its relatively high radioactivity. Meanwhile, sands of the middle and eastern zones are recommended for the same target, after separation the economic and strategic minerals of strategic importance.
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