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The volume magnetic susceptibility of moist air ?m(ma) is needed to correct the results of certain experiments to vacuum conditions. This paper derives an appropriate equation for ?m(ma) for which pressure, temperature, relative humidity, and carbon dioxide content are variable parameters. The derived equation also depends sensitively on the molar susceptibility of oxygen, for which the handbook values are inconsistent by about 1.4%. The equation resolves this discrepancy in part.

The influence of genetic factors on the manifestations of disease associated with infection with Schistosoma mansoni (portal hypertension, liver granulomas, hepatosplenomegaly) and their modulation were studied in inbred strains of mice. Three groups were identified according to the degree of portal hypertension: high (portal venous pressure, 19.1 cm H2O: DBA/1J), intermediate (8.9-13.4 cm H2O; BALB/cJ, DBA/2J, CBA/CaJ, C3H/HeJ, and BUB/BnJ), and low responders (6.1 cm H2O; C57BL/6J). Granuloma size, organomegaly, and portal venous pressure were strain dependent and not H-2 dependent and were determined by more than one gene. Studies of schistosomiasis in the F1 generation of high and low responders indicated that more than one gene is involved. Modulation of portal venous pressure between eight and 20 weeks of infection occurred in C57BL/6J but not in BALB/cJ mice and was transferable with immune lymphoid cells. These data indicate that disease associated with infection with S. mansoni and its modulation in mice are influenced by the genetic (non-H-2) background of the host and dependent in part on cell-mediated immunity.

Tensile stress-strain curves are reported for aluminum single and bicrystal specimens. Isoaxial bicrystal specimens were used with one crystal rotated 45° about the stress axis with respect to the other. The axial orientations were chosen so that one, two, four, six, or eight slip systems were initially equally favored. The 45° grain boundary did not raise the stress-strain curve of the bicrystal above that of the corresponding single crystal if two or more slip planes were initially equally favored.

A new technique has been developed by which naturally and anodically formed aluminum oxide produced on single‐crystal specimens has been studied in the electron microscope. The low‐temperature amorphous oxide grown by the transport of cations was smooth at the metal‐oxide interface. However, the oxide‐oxygen interface exhibited topography on certain crystal orientations. A high‐temperature crystalline oxide was found to grow by the transport of anions. Epitaxial growth was observed on several orientations. The anisotropy of oxide thickness which occurred at elevated temperatures is discussed.The above results are considered in terms of the structure of the metal‐oxide interface.

Shock‐induced phase transformations in iron have been investigated in the temperature range 78° to 1158°K. The pressure for transformation over this temperature range has been determined by a technique that depends on microstructural changes associated with a phase transformation. A discontinuity in the temperature‐pressure relationship was observed at 115 kbars and 775°K. Two distinct transformation microstructures were observed. It is postulated that the results obtained above 775°K are due to the expected transformation from alpha iron to gamma iron whereas the results below 775°K are related to a transformation from alpha iron to a presently undetermined new phase.

A circuit is presented that makes use of low frequency square waves for exciting resistance bridges, detecting their departure from balance, and providing an output voltage for measurement or control purposes. Applications in several areas of precision metrology have been found.

An outbreak of amikacin-resistant Enterobacteriaceae (KES) occurred in the Intensive Care Nursery (ICN) of the Louisville General Hospital from January 1978 through March 1978. Epidemic disease and an increased colonization rate in newborn infants due to amikacin-resistant microorganisms has not been documented previously. Three of the 11 neonates died. The organisms isolated were resistant to amikacin and two experimental aminoglycosides, sissomicin and netilmicin. The outbreak was contained following institution of several control measures, including pharyngeal inoculation of an experimental strain of alpha streptococcus in four infants.

Ray tracing in a layered atmosphere is accomplished by using a general‐purpose analog computer. Diode function generators are used to simulate the functions V and dV/dy, which are continuous functions defined for all values of range and altitude. It is shows that these diode function generators approximate quite well the speed of sound profiles.

A spherical acoustic resonator has been used to redetermine the universal gas constant R with an uncertainty of 1.8 ppm (standard deviation). To accomplish this, three subtasks were completed. (1) The volume of a spherical shell was determined by weighing the mercury required to exactly fill it at the temperature of the triple point of water, 273.16 K. (2) With the resonator filled with commercially supplied argon, the resonance frequencies of the radial modes were measured as a function of pressure. Using our theoretical model for the cavity, the frequency measurements were combined with the mean resonator radius determined in subtask (1) to obtain the speed of sound in commercially supplied argon. (3) Finally, the speed of sound in the commerically supplied argon was compared to the speed of sound in a “standard” sample whose chemical and isotopic composition was accurately established.