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The presence of research regarding specific student populations demonstrates their importance to the field given the importance of research and knowledge creation in shaping higher education. A growing number of higher education scholar-practitioners have engaged in work addressing college sport but an overwhelming dearth of college sport and athlete-focused higher education research in higher education journals is cause for concern. The purpose of this study is to investigate the presence of college sport research within high impact, general higher education journals between 2010–2019. Using content analysis, the authors examined seven highly regarded higher education journals. Findings support the hypothesis that an absence of sport-related research exists in such journals. Suggestions to address this gap are provided.

The proximity of the iris to the instruments and currents of cataract surgery makes iatrogenic damage to the iris a common complication of cataract surgery. This article discusses techniques to prevent or minimize this damage. When damage does occur, the surgeon must decide if, when, and how to repair the damage. Principles governing these decisions and techniques for repair are discussed. Figures and videos, included as online Supplemental Data files, illustrate cases of iatrogenic damage and repair techniques.

The high cost of commercial supplements necessitates evaluation of alternatives for ruminant livestock fed poor quality warm-season grasses. This study determined how supplementing bahiagrass haylage (Paspalum notatum Flügge cv. Tifton 9) with soybean [Glycine max (L.) Merr.] meal or warm-season legume haylages affected the performance of lambs. Forty-two Dorper x Katadhin lambs (27.5 +/- 5 kg) were fed for ad libitum intake of bahiagrass haylage (67.8% NDF, 9.6% CP) alone (control) or supplemented with soybean meal (18.8% NDF, 51.4% CP) or haylages of annual peanut [Arachis hypogaea (L.) cv. Florida MDR98; 39.6% NDF, 18.7% CP], cowpea [Vigna unguiculata (L.) Walp. cv. Iron clay; 44.1% NDF, 16.0% CP], perennial peanut (Arachis glabrata Benth. cv. Florigraze; 40.0% NDF, 15.8% CP), or pigeonpea [Cajanus cajan (L.) Millsp. cv. GA-2; 65.0% NDF, 13.7% CP]. Haylages were harvested at the optimal maturity for maximizing yield and nutritive value, wilted to 45% DM, baled, wrapped in polyethylene plastic, and ensiled for 180 d. Legumes were fed at 50% of the dietary DM, and soybean meal was fed at 8% of the dietary DM to match the average CP concentration (12.8%) of legume haylage-supplemented diets. Lambs were fed each diet for a 14-d adaptation period and a 7-d data collection period. Each diet was fed to 7 lambs in period 1 and 4 lambs in period 2. Pigeonpea haylage supplementation decreased (P0.01) DM and OM intake and digestibility vs. controls. Other legume haylages increased (P0.05) DM and OM intake vs. controls; however, only soybean meal supplementation increased (P = 0.01) DM digestibility. All supplements decreased (P = 0.05) NDF digestibility. Except for pigeonpea haylage, all supplements increased (P0.01) N intake, digestibility, and retention, and the responses were greatest (P = 0.04) with soybean meal supplementation. Microbial N synthesis was reduced (P = 0.02) by pigeonpea haylage supplementation, but unaffected (P = 0.05) by other supplements. Efficiency of microbial protein synthesis was unaffected (P = 0.05) by diet. Ruminal ammonia concentration was increased (P = 0.01) by all supplements, but only soybean meal and annual peanut haylage increased (P0.03) plasma urea-N concentrations. Perennial peanut, annual peanut, and cowpea haylages are promising protein supplements for growing lambs.

NASA has been making statistical measurements of the orbital debris environment for more than a decade using the MIT Lincoln Laboratory Haystack radar. The goal has been to characterize the environment for debris sizes as small as possible. Like all sensors which operate in the presence of noise, the Haystack radar has limited sensitivity. As the returned energy from small targets begins to approach the sensitivity limit of the radar, the probability-of-detection decreases, eventually approaching zero. The slope of the cumulative size distribution of debris begins to flatten out. This paper explores the possibility of extending the cumulative size distribution to smaller sizes by adjusting the distribution for probability-of-detection.

Efficient transduction of primary human T cells is an important goal toward treating a number of genetic defects. Patient T cells could be harvested by leukapheresis, transduced, and returned to the donor. A wide range of secreted or cell surface therapeutic proteins may be delivered in this way. The ability to produce antibodies is the consequence of interactions between T cells and B cells and lack of expression of CD40 ligand (CD40L) on T cells causes X-linked hyper-IgM syndrome (XHIM). We are investigating delivery of a normal CD40 ligand to treat this disorder. We tested promoters driving the expression of either reporter genes such as enhanced green fluorescent protein (eGFP) or human CDC40L. Using murine retroviruses, the best able to drive gene expression in T cells was the cytomegalovirus (CMV) promoter enhancer element; however, transduction efficiency was low. To achieve efficient, high-level gene expression we tested lentiviral gene delivery vectors. At a low multiplicity of infection (MOI) (0.5-2) a large fraction of target cells was transduced by lentiviral vectors (40-93%), and the strength of gene expression was high, as determined by flow cytometric analysis. We monitored the expression of eGFP or human CD40L on T cell lines and untransformed primary human T cells from normal and CD40L-deficient patients. We achieved efficient gene expression without an extended exposure to virus, and without the need for selection. These results are encouraging for efficient lentivirus-mediated transduction of refractory human cells to achieve therapeutic gene delivery.

Passive microwave data have been used to infer the snow-covered area and snow water equivalent (SWE) over forested areas, but the accuracy of these retrieved snow parameters cannot be easily validated for heterogeneous vegetated regions. The Boreal Ecosystem-Atmosphere Study Winter Field Campaign provided the opportunity to study the effect of boreal forests on snow parameter retrieval in detail. Microwave radiometers (18, 37, and 92 GHz) were flown on board the Canadian National Aeronautical Establishment's Twin Otter. Flight lines covered both the southern study area near Prince Albert and the northern study area near Thompson, Canada. During the 1994 winter campaign, extensive ground-based snow cover information, including depth, density, and grain size, was collected along most of the flight lines, jointly by U.S. and Canadian investigators. Satellite data collected by the special sensor microwave imager are also used for comparison. Preliminary results reconfirmed the relationship between microwave brightness temperature and SWE. However, the effect of forest cover observed by the aircraft sensors is different from that of the satellite observations. This is probably due to the difference in footprint averaging. There were also several flight lines flown over Candle Lake and Waskesiu Lake to assess lake ice signatures. Preliminary results show the thickness of the lake ice may be inferred from the airborne microwave observations. The microwave signature relationship between lake ice and snow matches the results from radiative transfer calculations.

The amphotropic murine leukemia virus (MuLV) can infect cells from a number of mammals, including humans, via its specific receptor. Basic knowledge of amphotropic MuLV receptor expression is likely to be useful in the development and improvement of gene therapy protocols based on amphotropic-pseudotyped vectors. To investigate the expression of the human receptor for the amphotropic MuLV (GLVR-2, newly termed Pit2), we determined its mRNA levels in several cell lines and found them to vary significantly. Induction of increased levels of mRNA after removal of phosphate from the media was observed in two osteosarcoma cell lines. The increase in GLVR-2 mRNA resulted in a concomitant rise in the levels of a 71-kDa protein specifically recognized by affinity-purified antibodies against GLVR-2. Using these antibodies, we were able to confirm the intracellular topology of the large hydrophilic domain between the proposed sixth and seventh transmembrane domains of the GLVR-2 protein. This assignment is in agreement with the fourth extracellular loop being outside the cell, consistent with the proposal that the fourth extracellular loop of GLVR-2 contains the envelope binding site.

HIV-1 Nef down-modulates expression of human CD4, the human immunodeficiency virus (HIV) receptor, at the cell surface. Down-modulation of retrovirus receptors has been shown to be important in the survival of infected cells. To relate this observation to AIDS pathogenesis, we compared the ability of Nef from the SIVmac239 open and HIV-1 SF2 isolates to suppress CD4 surface levels. We first obtained the simian immunodeficiency virus (SIV) nef gene by PCR and cloned it into the retroviral vector pLXSN. We then established high titer (1 × 106 CFU/ml) amphotropic retrovirus producer lines (PA317/LSnefSN). Using LSnefSN we obtained populations of CD4+ human and mouse T-cells, human B-cells, and mouse fibroblasts that expressed SIV or HIV Nef. In the two human cell lines, both HIV and SIV Nef expression correlated with a significant decrease in CD4 cell surface levels. However, Nef expression did not alter the cell surface levels of CD3, CD18, and MHC class I. Both Nef proteins also suppressed human CD4 surface expression in mouse fibroblasts. Interestingly, SIV Nef failed to suppress cell surface expression of mouse CD4 under conditions where HIV-1 Nef did. Human CD4 down-modulation is a conserved function of SIV and HIV Nef likely to be important for pathogenesis.

Human interleukin 1 beta (IL-1 beta) is synthesized as an inactive precursor that is cleaved by IL-1 converting enzyme (ICE) between Asp116 and Ala117 to form COOH-terminal mature IL-1 beta and NH2-terminal IL-1 beta propeptide. Little is known about the fate of the NH2-terminal cleavage product. In this study, human recombinant (hr)IL-1 beta propeptide (amino acids 2-116) was produced and used to prepare specific antibodies which do not recognize mature human IL-1 beta. These anti-propeptide antibodies were used for immunoprecipitation of biosynthetically labeled proteins from lipopolysaccharide-stimulated human monocytes. Analysis of immunoprecipitates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography revealed that these antibodies recognize precursor IL-1 beta and two unique proteins: one migrating at 17.5 kD and one at 14 kD. The larger of these two proteins has a migration nearly identical to that of the recombinant IL-1 beta propeptide, and most likely represents naturally derived propeptide. The protein migrating at 14 kD may result from a second cleavage by ICE, between Asp27 and Gly28. These proteins accumulate intracellularly and extracellularly during pulse-chase experiments, and therefore represent stable products of precursor IL-1 beta cleavage.

In this study a new microwave snow retrieval algorithm was developed to account for the effects of atmospheric emission on microwave radiation over high-elevation land areas. This resulted in improved estimates of snow-covered area in western China when compared with the meteorological station data and with snow maps derived from visible imagery from the Defense Meteorological Satellite Program satellite. Some improvement in snow-depth estimation was also achieved, but a useful level of accuracy will require additional modifications tested against more extensive ground data.

In situ and Landsat Thematic Mapper (TM)-derived reflectances of the Forbindels Glacier, Greenland, were acquired in August of 1986. Reflectance was measured in situ using a portable spectrometer and calculated using TM data and ancillary information. Atmospheric corrections were applied to the at-satellite reflectances resulting in a 5-17 percent increase in reflectance relative to the calculated at-satellite reflectances. The satellite-derived, corrected reflectances obtained from the non-saturated TM bands corresponded to within 6 percent of the in situ reflectances measured at the nadir viewing angle with a portable spectrometer. Measurement of nadir reflectances using Landsat-TM data appears to be a viable method to obtain physically meaningful reflectances of ice and snow.

To determine the most effective methods of increasing mammography adherence while also considering ease of intervention delivery in evolving healthcare systems.Experimental.Women from a health maintenance organization and a large general medicine practice.Women 50-85 years of age who had not had breast cancer and did not have a mammogram within the last 15 months.Once consent and baseline information were obtained, women were randomized to receive in-person, telephone, or no mammography counseling.Mammography adherence, perception of susceptibility to breast cancer, and benefits, barriers to, and knowledge of mammography.Compared to standard care, telephone counseling was more than twice as effective at increasing mammography adherence, whereas in-person counseling resulted in almost three times the mammography adherence postintervention. Both telephone and in-person counseling are successful in changing perceived susceptibility, knowledge, barriers, and benefits.Both telephone and in-person counseling interventions were successful in changing beliefs, which, in turn, increased mammography adherence.Interventions based on altering beliefs are effective for increasing mammography adherence.

Health professionals continue to seek strategies to help individuals increase health-promoting behaviors and decrease those behaviors related to unhealthy lifestyles. Various health behavior theories currently guide interventions that focus on health behavior changes. Of these, a tailored approach uses individual data on beliefs and behavior to guide the content and delivery of interventions. The purpose of this paper is to explain the usefulness of theories in tailoring health promotion messages to increase health-protecting behaviors.A brief overview of current popular theories that focus on individual behavior is presented, followed by illustrations of a tailored intervention approach for breast cancer screening. Applications of the tailored intervention approach in ongoing studies to increase breast cancer screening are described.Clinical implications of the ongoing projects suggest practical and widespread utility of tailoring health-promoting messages to increase healthy lifestyles. The tailored approach may be used by a multidisciplinary team to focus on the individual's unique factors to impact behavior change rather than to deliver the same standard message to all individuals.

Efforts have been made by several investigators to produce a reliable global microwave snow algorithm to estimate snow depth or snow water equivalent (snow volume) and snow extent. Complications arise when trying to apply a global algorithm to specific regions where the climate, snowpack structure and vegetation vary. In forest regions, the microwave emission from dense coniferous forests may overwhelm the emission from the underlying snow-covered ground. As a result, algorithms employing microwave data tend to underestimate snow depths. Preliminary results indicate that the amount of underestimation can be minimized when the fraction of forest cover can be accounted for and used as an additional input in microwave algorithms. In the boreal forest of Saskatchewan, the standard error between the measured and the estimated snow water equivalent was reduced from 2.7 to 2.1 cm by using a generalized snow retrieval algorithm that includes the percentage of forest cover. However, perhaps as much as 25% of the boreal forest of North America and Eurasia is too dense to enable satisfactory snow water equivalent determination to be made using passive microwave techniques alone. Key words: brightness temperature, boreal forest, microwaves, radiometer, snowpack

Low-resolution meteorological satellite data and simple photo interpretation techniques have been used to map snow-covered areas during early April over the Indus River and Kabul River basins in Pakistan. The early spring snow-covered area was significantly related to April 1 through July 31 Streamflow in regression analyses for each watershed (Indus River, 1969–1973, r2 = 0.82, and Kabul River, 1967–1973, r2 = 0.89). Predictions of 1974 seasonal Streamflow using the regression equations were within 7% of the actual 1974 flow. Because of inadequate hydrometeorological data, conventionally based Streamflow predictions are not possible in some of these remote regions, and the satellite-derived runoff estimates have immediate applicability for improved water resources management.

The snow-pack on the Arctic Coastal Plain of Alaska has a well-developed depth-hoar layer which forms each year at the base of the snow-pack due to upward vapor transfer resulting from a temperature gradient in the snow-pack. The thickness of the depth-hoar layer tends to increase inland where greater temperature extremes (in particular, lower minimum temperatures) permit larger temperature gradients to develop within the snow-pack. Brightness temperature (TB) data were analyzed from October through May for four winters using the 37 GHz horizontally polarized Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR). By mid-winter each year, a decrease inTBof approximately 20K was found between coastal and inland sites on the Arctic Coastal Plain of Alaska. Modeling has indicated that a thicker depth-hoar layer in the inland sites could be responsible for the lowerTBs. The large grain-sizes of the depth-hoar crystals scatter the upwelling radiation moreso than do smaller crystals, and greater scattering lowers the microwaveTB. Using a two-layered radiative transfer model, the crystal diameter in the top layer was assumed to be 0.50 mm. The crystals in the depth-hoar layer may be 5–10 mm in diameter but the effective crystal diameter used in the radiative-transfer model is 1.40 mm. The crystal size used in the model had to be adjusted downward, relative to the actual crystal size, because the hollow, cup-shaped depth-hoar crystals are not as effective at scattering the microwave radiation as are spherical crystals that are assumed in the model. In the model, when the thickness of the depth-hoar layer was increased from 5 cm to 10 cm, a 21K decrease inTBresulted. This is comparable to the decrease inTBobserved from coastal to inland sites in the study area.

Angular distributions for elastic and inelastic scattering have been measured on six analog resonances in the $^{130}\mathrm{Te}$+p system and at two off resonance energies. Partial widths are deduced from the angular distributions. Formulae for the spectroscopic amplitudes within the framework of the quasiparticle random phase approximation are presented. The experimental results are compared with the theoretical predictions.[NUCLEAR REACTIONS $^{130}\mathrm{Te}$(p,p\ensuremath{'}), $E=7.5\ensuremath{-}14$ MeV; enriched targets, measured $\ensuremath{\sigma}({E}_{\mathrm{p}},\ensuremath{\theta})$; deduced spectroscopic amplitudes; $^{131}\mathrm{Te}$ calculated and spectroscopic amplitudes predicted.]

Angular distributions for elastic and inelastic scattering have been measured on six analog resonances in the /sup 130/Te+p system and at two off resonance energies. Partial widths are deduced from the angular distributions. Formulae for the spectroscopic amplitudes within the framework of the quasiparticle random phase approximation are presented. The experimental results are compared with the theoretical predictions.

A preclinical investigation has been made of the effects of microwave heating in enhancing the response of pig skin to X-rays. Areas on the flanks of Large White English pigs were treated with X-rays alone or with X-rays followed by heating at 42°C for 1.5 hours. The treatment was given as a single dose or as three fractions over six days. Heating was produced with a microwave direct-contact applicator operating at 2.45 GHz. The early skin reaction was scored quantitatively by an arbitrary numerical system. For all treatments, microwave heating was shown to have little effect in enhancing the response of pig skin to ionizing radiation.

Angular distributions of the cross section for the elastic and inelastic scattering of protons have been measured at four isobaric analog resonances of the /sup 144/Sm+p system and at two off-resonance energies. Spectroscopic information about the (7/2)/sub 1//sup -/, (3/2)/sub 1//sup -/, (1/2)/sub 1//sup -/, and (5/2)/sub 1//sup -/ states of the parent nucleus /sup 145/Sm is extracted, with the core /sup 144/Sm in the states 0/sub 1//sup +/, 2/sub 1//sup +/, 3/sub 1//sup -/, 4/sub 1//sup +/, and 2/sub 2//sup +/. The analysis includes direct and fluctuating nonresonant processes. The direct scattering amplitude is obtained from a coupled channel treatment. Different methods for the calculations of the single-particle widths have been employed. The experimental spectroscopic amplitudes were compared with nuclear structure calculations based on the particle-vibrator model. Both the liquid drop model and the quasi-particle random phase approximation were used to describe the vibrator. The calculations based on the latter model show good agreement with the experimental results.

The severity of skin contraction in a previously delimited treatment field has been used as a measure of late radiation damage to pig skin. Total treatment doses were given as 6, 14, and 30 fractions over 39 days or as 6 fractions over 18 days. Iso-effect curves for severe linear field contraction showed that no simple mathematical formula could be used to calculate safe "tolerance" doses when fractionation regimes were modified. The results do indicate that for a given level of acute damage, late damage was increased by changing from 5 to 2 fractions per week. These findings are similar to those obtained from surveys in man.

cAMP-dependent protein kinase has been purified to homogeneity from adult bodies of Drosophila melanogaster. It is tetrameric in structure with two regulatory and two catalytic subunits that dissociate when activated by cAMP. The regulatory subunit exists in phospho and dephospho forms, which have electrophoretic mobilities in sodium dodecyl sulfate-polyacrylamide gels corresponding to Mr = 58,000 and 52,000, respectively. The catalytic subunit has a molecular weight of 40,000. The holoenzyme has a Stokes radius of 4.7 nm. The Km for activation by cAMP is substrate-dependent with Km values of 20 nM with histone H2B and 100 nM with the peptide, Leu-Arg-Arg-Ala-Ser-Leu-Gly. These physical and kinetic properties are very similar to those of the bovine heart Type II cAMP-dependent protein kinase. A Drosophila Type I cAMP-dependent protein kinase was also found in larval stages and during the first half of pupation but was absent in embryos and adults. The fly Type II enzyme was present in all developmental stages. Three regions of the Drosophila genome were found which, when present in three copies, significantly alter the specific activity of cAMP-dependent protein kinase. These are located at 29F-33F (30% increase), 46A-50C (17% increase), and 66B-67D (16% decrease).

Microwave signatures have been found to be related to variations in snow conditions found on the earth's surface. Most of these observations have been obtained by passive microwave radiometry. In general, inverse relationships between microwave brightness temperature (TB) and snow depth were observed for dry snowpacks. The results from truck-mounted scatterometers indicated that the backscattering cross sections from snowpacks increased with snow depths, also in dry snow conditions. The reported aircraft mission was the first trial in which simultaneous active and passive microwave measurements were made over a wet snowpack. The test site was located in the Colorado Rocky Mountains. The results from this experiment suggest that microwave techniques using both radiometers and scatterometers may be useful in determining snow water equivalent even when the snowpack is wet.

ERTS-1 satellite imagery was evaluated as a means of providing useful watershed physiography information. From these data physiographic parameters such as drainage basin area and shape, drainage density, stream length and sinuosity, and the percentage of a watershed occupied by major land use types were obtained in three study areas. The study areas were: (1) Southwestern Wisconsin; (2) Eastern Colorado, and (3) portions of the Middle Atlantic States. Using ERTS-1 imagery at 1:250,000 and 1:100,000 scales it was found that drainage basin area and shape and stream sinuosity were comparable (within 10%) in all study areas to physiographic measurements derived from conventional topographic maps at the same scales.

The cytocidal properties of metronidazole against hypoxic mammalian cells are described. This chemotherapeutic action has been shown to be dependent on drug concentration and duration of exposure. The x-ray TCD50 for a murine anaplastic carcinoma was reduced from 6081 rad to 4643 rad when animals were given metronidazole orally for 36 h before radiation treatment. The effect is attributed to the direct killing of hypoxic tumour cells by a mechanism analogous to that proposed for the action of the drug on anaerobic micro-organisms. It is concluded that further work with metronidazole as a cytotoxin specific for hypoxic cells is warranted, particularly in view of the reported lack of toxicity associated with the preliminary clinical use of the drug as a radiosensitizer in man.

The radiosensitizing properties of metronidazole have been studied using bacteria, bean roots, and mammalian cells in vitro as test systems. Metronidazole has been shown to sensitize only anoxic cells in a concentration-dependent manner, a maximum enhancement ratio of 1·9 being obtained at 8 mmol/1. metronidazole concentration for mammalian cells. The effect of added SH compounds on the sensitizing effect of metronidazole was studied in bacteria and bean roots. Metronidazole sensitized bacteria to the effects of neutron irradiation by a factor of only 1·4. The mechanism of sensitization by metronidazole is discussed in the light of pulse radiolysis and ESR data, and its action compared with that of oxygen. Pharmacological data presented suggest that in vivo testing of metronidazole should be possible and that any radiosensitizing effects shown may be related to measured serum concentrations.

Cross-section and analyzing power angular distributions have been measured for 20 Ne(p, p) 20 Ne and 20 Ne(p, p 1 ) 20 Ne ∗ (1.63 MeV) for proton energies between 3.7 and 7.9 MeV. The measurements were made in 25 keV intervals between 3.7 and 4.4 MeV, and in 10 keV intervals over most of the region between 4.4 and 7.9 MeV. A phase-shift analysis of the elastic-scattering data has yielded resonance parameters for thirty-three levels in 21 Na in the excitation energy region 6.0–9.9 MeV. Some of the strong even-parity resonances can be understood within the framework of the Nilsson model or the shell model. These resonances are also predicted by a macroscopic coupled-channels calculation involving rotational excitation of the 2 + and 4 + states of 20 Ne.

A reversible interconversion of two kinetically distinct forms of hepatic pyruvate kinase regulated by glucagon and insulin is demonstrated in the perfused rat liver. The regulation does not involve the total enzyme content of the liver, but rather results in a modulation of the substrate dependence. The forms of pyruvate kinase in liver homogenates are distinguished by measurements of the ratio of the enzyme activity at a subsaturating concentration of P-enolpyruvate (1.3 mM) to the activity at a saturating concentration of this substrate (6.6 mM). A low ratio form of pyruvate kinase (ratio between 0.1 and 0.2) is obtained from livers perfused with 10(-7) M glucagon or 0.1 mM adenosine 3':5'-monophosphate (cyclic AMP). A high ratio form of the enzyme is obtained from livers perfused with no hormone (ratio = 0.35 to 0.45). The regulation of pyruvate kinase by glucagon and cyclic AMP occurs within 2 min following the hormone addition to the liver. Insulin (22 milliunits/ml) counteracts the inhibition of pyruvate kinase caused by 5 X 10(-11) M glucagon, but has only a slight influence on the enzyme properties in the absence of the hyperglycemic hormone. The low ratio form of pyruvate kinase obtained from livers perfused with glucagon or cyclic AMP is unstable in liver extracts and will revert to a high ratio form within 10 min at 37 degrees or within a few hours at 0 degrees. Pyruvate kinase is quantitatively precipitated from liver supernatants with 2.5 M ammonium sulfate. This precipitation stabilizes the enzyme and preserves the kinetically distinguishable forms. The kinetic properties of the two forms of rat hepatic pyruvate kinase are examined using ammonium sulfate precipitates from the perfused rat liver. At pH 7.5 the high ratio form of the enzyme has [S]0.5 = 1.6 +/- 0.2 mM P-enolpyruvate (n = 8). The low ratio form of enzyme from livers perfused with glucagon or cyclic AMP has [S]0.5 = 2.5 +/- 0.4 mM P-enolpyruvate (n = 8). The modification of pyruvate kinase induced by glucagon does not alter the dependence of the enzyme activity on ADP (Km is approximately 0.5 mM ADP for both forms of the enzyme). Both forms are allosterically modulated by fructose 1,6-bisphosphate, L-alanine, and ATP. The changes in the kinetic properties of hepatic pyruvate kinase which follow treating the perfused rat liver with glucagon or cyclic AMP are consistent with the changes observed in the enzyme properties upon phosphorylation in vitro by a clyclic AMP-stimulated protein kinase (Ljungstrom, O., Hjelmquist, G. and Engstrom, L. (1974) Biochim. Biophys. Acta 358, 289--298). However, other factors also influence the enzyme activity in a similar manner and it remains to be demonstrated that the regulation of hepatic pyruvate kinase by glucagon and cyclic AMP in vivo involes a phosphorylation.

The reaction 144 Sm(p, p') has been measured on four analog resonances in the 144 Sm+p system at incident proton energies of 9.315, 10.205, 10.910 and 10.980 MeV. In addition to highly excited levels with large neutron particle-hole components, low-lying states in 144 Sm also resonate because of neutron coupling to these levels in the parent system. Spectroscopic factors are extracted for states, the spin of which is known or indicated by this experiment.

The excited states of 142 Nd were studied by means of the decay of 40 sec 142 Pm and the 142 Nd(p, p') reaction via isobaric analog resonances. Approximately sixty levels of 142 Nd were observed below 5.3 MeV excitation, including several neutron particle-hole states excited strongly in (p, p') at f 7 2 , p 3 2 , p 1 2 and f 5 2 analog resonances. We have collected together all known energy levels in 142 Nd and have proposed J π assignments for 22 excited states. We have also compared the experimental level spectrum (positive-parity states only) with a calculated one based on the shell model.

The serum concentrations of the radiosensitizer metronidazole have been determined in mice for both oral and intraperitoneal doses of the drug and these have been related to radiosensitization studies in murine tumour systems. In preliminary work before a possible clinical trail the serum metronidazole concentration/time curves have been determined in 7 patients using single doses of metronidazole of up to 15 g. The data suggest that a linear relationship exists between the metronidazole dose expressed in mg/kg and the peak serum concentration. The possibility of achieving radiosensitization of tumours in patients after tolerable doses of metronidazole is discussed in relation to enhancement ratios determined for in vitro and in vivo systems. It is concluded that predictions from in vitro systems give values that are probably too optimistic.