Origin, evolution and present thermal state of the moon

The relative absence of lunar volcanism in the last 3 b.y. and the Apollo 15 heat flow measurement suggest that present-day temperatures in the moon are approximately steady state to depths of 100 km. An exponential distribution of heat sources with depth is scaled by equating the surface heat flow to the integrated heat production of this exterior shell. Presumed present-day interior temperatures and the present-day surface heat flow of 30 ergs/cm2-sec are obtained. The estimated homogeneous concentrations of U, the chemistry of the lunar surface material and inferences to modest depth, and the short accretion time of the moon necessary to provide large-scale differentiation at 4.6 AE suggest that the moon had its origin in the rapid accretion of compounds first condensing from the protoplanetary nebula. The present thermal state of the moon may involve at least some partial melting through all the lunar interior deeper than 200 km. Such a thermal configuration is inconsistent neither with temperatures inferred from electrical conductivity studies nor with the nonhydrostatic shape of the moon

Surface Roughness of Electron Beam Melting TI-6AL-4V Effect on Ultrasonic Testing

Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of Electron Beam Melted (EBM) additively manufactured Ti-6Al-4V. Additive Manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include, Aircraft Battle Damage Repair (ABDR), small batch manufacturing to fill supply gaps, and replacement for obsolete parts. The research presented here assesses the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM manufactured Ti-6Al-4V. EBM products are known to have high surface roughness in as-manufactured condition, and surface roughness is known to affect the results of ultrasonic inspections. The experimental data from this research demonstrates the ability of ultrasonic inspections to identify flaws as small as 0.51 mm at 2.25 MHz, 5 MHz and 10 MHz through a machined surface. A frequency of 10 MHz provides better results than 2.25 MHz and 5 MHz through an as manufactured surface, where the highest natural surface roughness is present

Metamorphism, argon depletion, heat flow and stress on the Alpine fault

The Alpine fault of New Zealand is a major continental transform fault which was uplifted on its southeast side 4 to 11 km within the last 5 m.y. This uplift has exposed the Haast schists, which were metamorphosed from the adjacent Torlesse graywackes. The Haast schists increase in metamorphic grade from prehnite-pumpellyite facies 9-12 km from the fault through the chlorite and biotite zones of the greenschist facies to the garnet-oligoclase zone amphibolite facies within 4 km of the fault. These metamorphic zone boundaries are subparallel to the fault for 350 km along the strike. The K-Ar and Rb-Sr ages of the schists increase with distance from the fault: from 4 m.y. within 3 km of the fault to approximately 110 m.y. 20 km from the fault. Field relations show that the source of heat that produced the argon depletion aureole was the fault itself

Radioautographic Evidence of 3H-Tryptophan Incorporation in Secretory Cells of Rat Submandibular Glands

Tritiated tryptophan was injected intravenously into male rats, and the submandibular glands were removed at time intervals up to three hours after injection. Grain counts were made on light and electron microscope radioautographs to determine the effects on the amino acid.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67201/2/10.1177_00220345710500064601.pd

Biochemical and Morphological Studies of Rat Submandibular Gland: III. Effects of Testosterone Treatment on Proteins of Granule-Rich Fraction

Mature adult male rats and castrated and testosterone-treated castrated adult rats were injected with pilocarpine HGL and 3-H-lysine and sacrificed sequentially over an eight-hour time period. Following homogenization and differential centrifugation, three subcellular fractions from each group of animals were analyzed by gel electrophoresis and liquid scintillation. Two proteins in the granule-rich fraction appeared in larger amounts on the densitometric scans and appeared to represent a larger proportion of newly synthesized proteins than the other proteins.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66712/2/10.1177_00220345770560030901.pd

Implications of an Elastic Analysis of In Situ Stress Measurements Near the San Andreas Fault

Twenty-nine measurements of in situ stress obtained with the hydraulic fracturing technique near Palmdale, California, are the basis of an elastic analysis of the state of stress in the Mojave Desert adjacent to the San Andreas fault. The measurements were made at depths extending from 80 to 849 m and at distances from the fault between 2 and 34 km. The elastic solution indicates a state of deviatoric stress typical for continents in that the inferred depth gradient of the maximum shear stress is about 7.9 MPa/km. Extrapolation yields an average shear stress in the upper 14 km of the crust of about 56 MPa, a result that is higher than estimates of the average shear stress on the San Andreas fault based on the analysis of heat flow data. This finding is consistent, however, with estimates offault strength based on laboratory determinations of the coefficient of friction for samples of San Andreas fault gouge if the regional state of deviatoric stress is limited by the strength of the fault zone. If so, then the coefficient of friction of the San Andreas fault zone inferred from the stress field results is about 0.45. The state of stress does not appear to vary systematically with distance from the San Andreas fault although considerable localized variation is observed. The observations suggest an upper bound of about 0.1 MPa/km for the horizontal gradient of the maximum shear stress in the direction perpendicular to the San Andreas fault, a result that implies a corresponding limit of about 1.4 MPa on the shear traction applied to the base of the seismogenic layer. Finally, we demonstrate the potential application of in situ stress data to the direct assessment of accumulated slip, which could be released in a large earthquake. We show that on the basis of a model involving a locked fault, extending to about 22 km, the total fault slip below the locked portion is less than 13 m. A more comprehensive set of stress data could permit the estimation of an even lower bound

Protein synthesis in vitro , in the presence of Ca(OH) 2 -containing pulp-capping medicaments

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73494/1/j.1600-0714.1983.tb00348.x.pd

Effect of Surface Roughness on Ultrasonic Inspection of Electron Beam Melting Ti‐6AL‐4V

Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products have a high surface roughness in “as-manufactured” condition which is an artifact of the manufacturing process. The surface roughness is known to affect the results of ultrasonic inspections. Experimental data from this research demonstrate the ability of ultrasonic inspections to identify imbedded flaws as small as 0.51 mm at frequencies of 2.25, 5 and 10 MHz through a machined surface. Detection of flaws in higher surface roughness samples was increased at a frequency of 10 MHz opposed to both lower frequencies tested

The Expression of the Epithelial Blood-group Substances: Normal and Malignant Tissues

The blood-group isoantigens are macromolecules localized to the plasma membranes of certain epithelial tissues.2,11-15 These substances are not detectable on the epithelium once it has undergone malignant transformation.2,9,13 Results of this investigation have demonstrated that the loss of detectability of the blood-group isoantigens does not appear to be related to a "masking" effect by an increase in surface sialic acid. Using fluorescein-labeled lectins specific for sugar subunits which are components of the blood-group oligosaccharide chain, it was found that the malignant cells and cells of the para basal layer of normal oral epithelium had high levels of N-acetyl-D-glucosamine (GlcNAC), the subterminal sugar residue of the blood-group chain. The basal cells of normal epithelium and a minority of the malignant cells demonstrated levels of D-galactose-N-acetyl-D-galactosamine, which are the most proximal blood-group sugar subunits, as well as subunits of other membrane antigens. Our results indicate that malignant cells seem to be capable of synthesizing the blood-group oligosaccharide chains to the same level as the normal cells of the para basal layer of stratified squamous epithelium. This level is just subjacent to the terminal D-galactose residue of the blood-group precursor chain. Increased or decreased differentiation characteristics of squamous cell carcinomas did not alter the level of blood-group synthesis. However, there may be a correlation between the level of synthesis of these antigens and the ability of the cells to demonstrate motility and to proliferate.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66719/2/10.1177_00220345800590112001.pd