scholarly journals The visualization of flow paths in experimental studies of clay-rich materials

2015 ◽  
Vol 79 (6) ◽  
pp. 1335-1342 ◽  
Author(s):  
A. C. Wiseall ◽  
R. J. Cuss ◽  
C. C. Graham ◽  
J. F. Harrington
Keyword(s):  
Deuterium Oxide ◽  
Experimental Studies ◽  
Ct Scanning ◽  
Pressure Vessels ◽  
The Body ◽  
British Geological Survey ◽  
Flow Paths ◽  
X Ray ◽  
Confining Pressures ◽  
Insight Into

AbstractOne of the most challenging aspects of understanding the flow of gas and water during testing in clay-rich low-permeability materials is the difficulty in visualizing localized flow. Whilst understanding has been increased using X-ray Computed-tomography (CT) scanning, synchrotron X-ray imaging and Nuclear Magnetic Resonance (NMR) imaging, real-time testing is problematic under realistic in situ conditions confining pressures, which require steel pressure vessels. These methods tend not to have the nano-metre scale resolution necessary for clay mineral visualization, and are generally not compatible with the long duration necessary to investigate flow in such materials. Therefore other methods are necessary to visualize flow paths during post-mortem analysis of test samples. Several methodologies have been established at the British Geological Survey (BGS), in order to visualize flow paths both directly and indirectly. These include: (1) the injection of fluorescein-stained water or deuterium oxide; (2) the introduction of nanoparticles that are transported by carrier gas; (3) the use of radiologically tagged gas; and (4) the development of apparatus for the direct visualization of clay. These methodologies have greatly increased our understanding of the transport of water and gas through intact and fractured clay-rich materials. The body of evidence for gas transport through the formation of dilatant pathways is now considerable. This study presents observations using a new apparatus to directly visualize the flow of gas in a kaolinite paste. The results presented provide an insight into the flow of gas in clay-rich rocks. The flow of gas through dilatant pathways has been shown in a number of argillaceous materials (Angeli et al., 2009; Autio et al., 2006; Cuss et al., 2014; Harrington et al., 2012). These pathways are pressure induced and an increase in gas pressure leads to the dilation of pathways. Once the gas breakthrough occurs, pressure decreases and pathways begin to close. This new approach is providing a unique insight into the complex processes involved during the onset, development and closure of these dilatant gas pathways.

Investigating a Moche Cast Copper Artifact for Its Manufacturing Technology

2014 ◽  
Vol 1656 ◽  
pp. 95-109 ◽  
Author(s):  
Aaron Shugar ◽  
Michael Notis ◽  
Dale Newbury ◽  
Nicholas Ritchie
Keyword(s):  
Alloy Composition ◽  
Solidification Process ◽  
The Body ◽  
Raman Analysis ◽  
X Ray ◽  
Casting Technology ◽  
Forming Technology ◽  
Microchemical Analysis ◽  
Spectrum Imaging ◽  
Insight Into

ABSTRACTA Moche cast copper alloy object was investigated with focus on three main areas: the alloy composition, the casting technology, and the corrosion process. This complex artifact has thin connective arms between the body and the head, a situation that would be very difficult to cast. The entire artifact was mounted and polished allowing for complete microstructural and microchemical analysis, providing insight into the forming technology. In addition, gigapixel x-ray spectrum imaging was undertaken to explore the alloy composition and the solidification process of the entire sample. This process used four 30 mm2SDD-EDS detectors to collect the 150 gigabyte file mapping an area of 46 080 × 39 934 pixels. Raman analysis was performed to confirm the corrosion compounds.

scholarly journals Osteoporosis in acute fractures of the cervical spine: the role of opportunistic CT screening

2015 ◽  
Vol 23 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Osa Emohare ◽  
Alison Dittmer ◽  
Robert A. Morgan ◽  
Julie A. Switzer ◽  
David W. Polly
Keyword(s):  
Cervical Spine ◽  
Ct Scanning ◽  
The Body ◽  
Published Data ◽  
Mineral Density ◽  
Mean Values ◽  
X Ray ◽  
Acute Fracture ◽  
Ct Attenuation ◽  
Picture Archiving And Communication

OBJECT Recently published data make it possible to generate estimates of bone mineral density (BMD) by using CT attenuation; this innovation can save time and reduce costs. Although advanced age is associated with reduced BMD, especially in patients with a fracture of C-2, relatively few patients ever undergo formal dual x-ray absorptiometry studies. To the authors' knowledge, this is the first study to assess the utility of this technique in elucidating BMD in patients with an acute fracture of the cervical spine. METHODS Patients who presented to a Level I trauma center with an acute fracture of the cervical spine and underwent abdominal (or L-1) CT scanning either at admission or in the 6 months before or after the injury were evaluated. Using a picture-archiving and communication system, the authors generated regions of interest of similar size in the body of L-1 (excluding the cortex) and computed mean values for CT attenuation. The values derived were compared with threshold values, which differentiate between osteoporotic and nonosteoporotic states; age-stratified groups were also compared. RESULTS Of the 91 patients whose data were reviewed, 51 were < 65 years old (mean 43.2 years) and 40 were ≥ 65 years old (mean 80.9 years). The overall mean CT attenuation values (in Hounsfield units [HU]), stratified according to age, were 193.85 HU for the younger cohort and 117.39 HU for the older cohort; the result of a comparison between these two values was significant (p < 0.001). CONCLUSIONS Using opportunistic CT scanning, this study demonstrates the relative frequency of osteoporosis in acute fractures of the cervical spine. It also objectively correlates overall BMD with the known higher frequency of C-2 fractures in older patients. This technique harnesses the presence of opportunistic CT scans of the abdomen, which potentially reduces the need for the extra time and cost that may be associated with dual x-ray absorptiometry scanning.

Two methods of using X-ray Computed Tomography to predict carcass composition in sheep

2005 ◽  
Vol 2005 ◽  
pp. 42-42
Author(s):  
J. M. Macfarlane ◽  
R. M. Lewis ◽  
G. C. Emmans ◽  
J.M. Young ◽  
G. Simm
Keyword(s):  
Computed Tomography ◽  
Ct Scanning ◽  
Carcass Composition ◽  
The Body ◽  
Anatomical Landmarks ◽  
Cross Sectional ◽  
X Ray ◽  
X Ray Computed ◽  
Breed Selection ◽  
The Individual

X-ray computed tomography (CT) can be used to accurately assess carcass composition in sheep (Sehested, 1984; Young et al., 2001) both in research and commercially, as part of a breed selection programme. Two different CT scanning methods have been used: a) the reference scan method where tissue weights are predicted from tissue areas in a small set of cross-sectional scans at ‘anatomical landmarks’, and b) the Cavalieri method where a larger number of scans are taken along the body. It is of interest to examine the accuracy of evaluations made using these two methods and the individual merits of the two methods depending on their application.

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

Great Increase of Numbers of Virus Particles by Irradiating C3H Mouse Mammary Tumors Transplanted into Male Mice

1972 ◽  
Vol 30 ◽  
pp. 272-273
Author(s):  
P. J. Melnick ◽  
J. W. Cha ◽  
E. Samouhos
Keyword(s):  
Subcutaneous Tissue ◽  
Mammary Tumors ◽  
The Body ◽  
X Ray ◽  
Virus Particles ◽  
Mouse Mammary Tumors ◽  
Transplantable Tumors ◽  
C3h Mice ◽  
Cobalt Radiation ◽  
Enzyme Changes

Spontaneous mammary tumors in females of a high tumor strain of C3H mice were cut into small fragments that were Implanted into the subcutaneous tissue of the back of males of the same strain, where they grew as transplantable tumors. When about Cm. In diameter daily fractional radiation was begun, applied to the tumors, the rest of the body being shielded by a lead shield. Two groups were treated with 150 and 200 r X-ray dally, of half value layer 0.6mm. copper; a third group was treated with 500 r cobalt radiation dally. The primary purpose was to examine the enzyme changes during radiation, with histochemlcal technics.

Quantitative Analysis Of X-Ray Images From Geological Materials

1990 ◽  
Vol 48 (2) ◽  
pp. 244-245
Author(s):  
J. M. Paque ◽  
R. Browning ◽  
P. L. King ◽  
P. Pianetta
Keyword(s):  
Quantitative Analysis ◽  
Bulk Composition ◽  
Principal Component ◽  
Analytical Description ◽  
Bulk Sample ◽  
Geological Samples ◽  
X Ray ◽  
Software And Hardware ◽  
And Storage ◽  
Insight Into

Geological samples typically contain many minerals (phases) with multiple element compositions. A complete analytical description should give the number of phases present, the volume occupied by each phase in the bulk sample, the average and range of composition of each phase, and the bulk composition of the sample. A practical approach to providing such a complete description is from quantitative analysis of multi-elemental x-ray images.With the advances in recent years in the speed and storage capabilities of laboratory computers, large quantities of data can be efficiently manipulated. Commercial software and hardware presently available allow simultaneous collection of multiple x-ray images from a sample (up to 16 for the Kevex Delta system). Thus, high resolution x-ray images of the majority of the detectable elements in a sample can be collected. The use of statistical techniques, including principal component analysis (PCA), can provide insight into mineral phase composition and the distribution of minerals within a sample.

Morphology and Affinities of Ampelocissites Seeds (Vitaceae: Ampelopsis clade) from the Paleogene of Texas, USA

2020 ◽  
Vol 45 (3) ◽  
pp. 478-482
Author(s):  
Steven R. Manchester
Keyword(s):  
Computed Tomography ◽  
Cross Sections ◽  
Seed Coat ◽  
Ct Scanning ◽  
Seed Morphology ◽  
Early Eocene ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Fossil Seeds ◽  
Fossil Genus

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

Copper–oxygen Dynamics in Tyrosinase

2019 ◽  
Author(s):  
Nobutaka Fujieda ◽  
Sachiko Yanagisawa ◽  
Minoru Kubo ◽  
Genji Kurisu ◽  
Shinobu Itoh
Keyword(s):  
Catalytic Mechanism ◽  
Substrate Binding ◽  
Active Form ◽  
Copper Ion ◽  
Atomic Resolution ◽  
Oxygen Species ◽  
X Ray ◽  
Oxygen Dynamics ◽  
Insight Into ◽  
Copper Centre

To unveil the activation of dioxygen on the copper centre (Cu<sub>2</sub>O<sub>2</sub>core) of tyrosinase, we performed X-ray crystallograpy with active-form tyrosinase at near atomic resolution. This study provided a novel insight into the catalytic mechanism of the tyrosinase, including the rearrangement of copper-oxygen species as well as the intramolecular migration of copper ion induced by substrate-binding.<br>

Basic Concepts and Definitions of Allergology

2019 ◽  
Author(s):  
Zoran Vrucinic
Keyword(s):  
Immune Reaction ◽  
The Body ◽  
The Other ◽  
Specific Response ◽  
Other Hand ◽  
Medical Vocabulary ◽  
The Future ◽  
Basic Concepts ◽  
Basic Insight ◽  
Insight Into

The future of medicine belongs to immunology and alergology. I tried to not be too wide in description, but on the other hand to mention the most important concepts of alergology to make access to these diseases more understandable, logical and more useful for our patients, that without complex pathophysiology and mechanism of immune reaction,we gain some basic insight into immunological principles. The name allergy to medicine was introduced by Pirquet in 1906, and is of Greek origin (allos-other + ergon-act; different reaction), essentially representing the reaction of an organism to a substance that has already been in contact with it, and manifested as a specific response thatmanifests as either a heightened reaction, a hypersensitivity, or as a reduced reaction immunity. Synonyms for hypersensitivity are: altered reactivity, reaction, hypersensitivity. The word sensitization comes from the Latin (sensibilitas, atis, f.), which means sensibility,sensitivity, and has retained that meaning in medical vocabulary, while in immunology and allergology this term implies the creation of hypersensitivity to an antigen. Antigen comes from the Greek words, anti-anti + genos-genus, the opposite, anti-substance substance that causes the body to produce antibodies.

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