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Stimulating rumination by feeding polypropylene ribbon had no effect in alleviating milk fat depression. In two experiments with six cows in each, milk fat depression was produced by feeding a ground pelleted hay with concentrates and limited long hay. Feeding this ration resulted in a large reduction in time spent ruminating. Adding polypropylene ribbon, 5 cm long, returned rumination times to normal but had no effect on milk fat depression. Replacing ground hay with long hay returned both rumination times and milk fat to normal. The effect of long hay in preventing or reversing milk fat depression is due to factors other than its potential for stimulation of rumination.

Particular solutions to the radiative transport equation are presented for an absorbing, emitting, and isotropic scattering medium with an arbitrary, but specified, temperature profile. The radiative transport is assumed to be one-dimensional and axisymmetric. Derivation of the particular solutions is based upon the method of variation of parameters. Homogeneous and particular solutions are derived from the discrete ordinate form of the radiative transport equation. The integration constants associated with the particular solution are expressed explicitly. This work yields a general solution which is expressed in closed form and is applicable to a wide range of problems involving radiative transport in absorbing, emitting, and scattering media. Also an illustrative example is presented for a medium having a linear temperature profile.

In an experiment performed at the CERN Intersecting Storage Rings (ISR), 11 e+e− pairs of high invariant mass value (> 2.5 GeV/c2) have been observed. Of these events, 9 can be interpreted as arising from the reaction p + p → J (3.1) + anything. the cross-section for this reaction is estimated and compared with the result obtained at lower centre-of-mass energies.

First-generation transplants of spontaneous mouse mammary carcinomas have been used extensively for radiobiological investigations of fractionated irradiation schedules, r.b.e. of fast neutrons and effectiveness of radiosensitizers, as reported elsewhere. The present work investigates the growth characteristics of the tumours; the criteria for the choice of end-points used in the definition of 'local control' of irradiated tumours; the reason for a decrease of 30 per cent in X-ray dose required to control tumours in females as compared with male mice; the proportion of hypoxic cells and its variation with time (reoxygenation) after a single dose of 1500 rad of X-rays; and the repair capacity of tumour cells within 24 hours after a substantial first dose of X-rays. Evidence is presented that the male-female difference was due to a higher proportion of hypoxic cells in tumours in male than in female mice. The repair of sub-lethal injury in tumour cells made hypoxic was slightly less than in skin made hypoxic but not significantly so. In the two-dose experiments on clamped tumours, no evidence of induced synchrony was found.

A search for high transverse momentum electrons directly produced in proton-proton collisions has been performed at the CERN ISR. The apparatus included a magnetic spectrometer with wire spark chambers, a lead-glass counter array, and a threshold gas Cerenkov counter. At a centre-of-mass energy √s = 52.7 GeV, a signal has been observed in the range 1.6 T ∗ GeV /c . The signal occurs at a level of approximately 10−4 of the inclusive pion cross-section.

Differential cross sections for π+p and π−p elastic scattering have been measured with an accuracy of typically ±2% at 10 and 9 energies respectively in the range 88 to 292 MeV of lab kinetic energy.

Neutron groups resulting from the alpha-particle bombardment of separated isotopes of potassium were observed. Ground-state Q values of -3.42 plus or minus 0.06 Mev for K/sup 4//sup 1/( alpha ,n)Sc/sup 4//sup 4/ and -7.16 plus or minus 0.06 Mev for s/sup 9/( alpha ,n)Sc/sup 4//sup 2/ were obtained. A large number of excited states or groupings of states were also observed. The presence of chlorine in one of the targets permitted measurement of the Cl/sup 3// sup 7/( alpha ,n)K/sup 4//sup 0/ reaction as well. A ground-state Q value of - 3.86 plus or minus 0.06 Mev was obtained. A tentative value of -5.89 plus or minus 0.06 Mev was given for the Cl/sup 3//sup 5/ ( alpha ,n)K/sup 3//sup 8/ ground state. (auth)

Dried sclerotia of Sclerotium rolfsii Sacc. rapidly rot in moist soil because they leak nutrients. The nutrients are an energy source for microorganisms in the vicinity of the sclerotia, giving them sufficient colonization potential to breach the defence mechanisms of the sclerotia. Drying the sclerotia also stimulates their germination in soil but further research is needed before the mechanism can be described. Dried sclerotia washed in water until all nutrient leakage is removed still germinate in soil but do not rot.

A comparison of some experimental beta spectra with theoretical predictions when the interaction is taken as a linear combination of the five usual forms has been made, and on this basis the conclusion is that the interaction can only be a mixture of the vector and tensor forms. For two disintegrations involving light nuclei the arbitrariness in the theoretical predictions has been reduced by assuming a shell structure of nuclei and evaluating the nuclear matrix elements involved. From this analysis it is concluded that the interaction responsible for beta decay is a mixture of approximately two parts of vector form to one of tensor.

Zephyr is a small low-power fast reactor with a core made up of plutonium and natural uranium sections surrounded by a uranium envelope. The reactor is controlled by moving sections of uranium near the core to vary the fraction of neutrons that may escape from the latter. Power level measurement is carried out by pulse-operated fission chambers with both linear and logarithmic ratemeters as indicators. The reactor became critical for the first time on the 5th February. Initial studies have included the investigation of the delayed neutrons and their influence on the reactor kinetics.

The light output of Csl(Tl) was measured as a function of energy for incident ions of B/sup 1//sup 0/, B/sup 1//sup 1/, C/sup 1//sup 2/, N/sup 1//sup 4/, O/sup 1//sup 6/, and F/sup 1//sup 9/. The response of NE 102 plastic and anthracene scintillators was also measured for ions of N/sup 1//sup 4/ and O/sup 1//sup 6/, respectively. The response of Csl was essentially linear for energies above 6 Mev/nucleon. The NE 102 was linear for energies above 4 Mev/nucleon. The anthracene data showed slight curvature even at 9 Mev/nucleon. The response of Csl appeared to differ somewhat among crystal samples. (auth)

Three experiments investigated how forages of different chemical composition affect rumination time of cattle. Three single reversal designs used four dairy heifers and two dairy steers in Experiment I and four dairy heifers in Experiments II and III. The rumination time produced by feeding a single 5-kg meal of test forage was measured with jaw motion recordings. In Experiment I the test meal was fed after 2 days of fasting; following the test meal no more was offered for an additional 2 days. In Experiments II and III only alfalfa pellets were offered during the 2 days before and after the test meal, at the rate of 2.27 kg per head per day. In Experiment I the animals which were fed straw ruminated 578 minutes following the test meal; the animals fed an excellent quality hay ruminated a shorter (P < .05) time of 369 minutes. Experiment II compared a good-quality mixed second-cutting hay with straw. The straw produced 539 minutes’ rumination time, and the second-cutting hay produced a shorter (P < .05) time of 387 minutes. In Experiment III good-quality orchardgrass produced 258 minutes’ rumination time; poor-quality orchardgrass produced a longer (P < .05) time of 449 minutes. The correlation between rumination time and cell wall constituent (CWC) content was 0.94.

1. 1. The body-component indices (ratio of component wet weight to the total wet weight) in Tivela stultorum remained relatively constant throughout the year except for a high gonad index during breeding when the fluid index decreased. 2. 2. The tissue protein level remained much the same throughout the year except for lower values in the gonads when they had accumulated carbohydrate and higher values during gametogenesis. 3. 3. The tissue lipid level was relatively low, being highest in digestive gland and gravid ovary. 4. 4. The tissue carbohydrate level was relatively high, especially in immature gonads. 5. 5. The gonads appear to accumulate their nutrient reserves for gametogenesis independently of other body components.

Initial research showed significant differences between individual cattle in their rumination response to equal amounts of cell wall constituent intake. Two further experiments were conducted to determine if dairy cattle breeds differ in their rumination time. In Experiment 2, eight Guernseys had lower (P < .05) 24-hour rumination times than did eight Holsteins, eight Ayrshires, and eight Jerseys. When corrected for cell wall constituent intake and body weight kilogram.75 the Guernsey average rumination time was lower than the Holstein average (P < .05) and the Jersey average (P < .01). In a third experiment eight lactating Guernseys averaged lower (P < .05) total rumination times, as well as minutes rumination corrected for cell wall constituent intake and body weight kilogram.75, than did eight lactating Jerseys.

A search has been made for electron pairs of large invariant mass produced in high-energy proton collisions at the CERN ISR. Data are presented for a centre-of-mass energy (√ s ) of 52.7 GeV. All electron pair candidates are believed to be consistent with background. Upper limits are obtained for the existence of massive objects decaying into electron pairs.

The ionisation loss of relativistic electrons in the energy range 20 – 150 MeV has been studied in CsI, Ne102A and an argon-methane mixture. No support has been found for Tsytovich's radiative corrections to energy loss.

Tests of Cambridge absolute filters, Model Sl-071, specified for use in the GCR-ORR Loop No. 2 as full-flow, primary coolant fiiters were completed. kD.O.P/ (dioctylphthalate) efficiency tests were performed on three filters in the as-received condition, on two filters following canning and thermal cycling, and on one of the canned fiIters following bsking out. None of the three units met the design criteria of 99.97% efficiency for removal of 0.3 micron particles in the as-received condition. The postthermal cycle efficiencies of the canned fiIters were slightly higher than their respective as-received efficiencies. At the corapletion of testing, the two fiiters canned for installation in the reactor facility had measured efficiencies of 99.855% and 99.93%. These values were judged acceptable for the intended application/su The thermal cycling of the two canned filters and the subsequent baking out of one of these units demonstrated that a limited amount of off-gas products would be given off/su Pressure drop tests were performed on the canned fiiters with instrument air (ambient temperature, atmospheric pressure) over a flow rate range of 150 to 530 lb/hr. Curves of pressure drop across each fiIter versus Reynolds number were plotted for air and He. (auth)

A photoreaction-diffusion model for the solar degradation of thermal control materials is mathematically formulated and analyzed. The governing differential equation for the concentration of defect specie created in the material by radiation is derived, and an analytical solution is obtained for appropriate boundary conditions. From this solution for the concentration of the ith-type defects, an analytical expression is derived for the number of ith- type defects present in a material layer of depth x and unit irradiated area. These analytical relations are used to predict the radiation-induced increase in the absorption coefficient and absorption optical thickness of a hypothetical thermal control material exposed to damaging ultraviolet irradiance equal to that of the sun. The solutions are also used to better define the environmental parameters which must be controlled during solar radiation testing of thermal control coatings. For example, the time-irradiance reciprocity principle often employed in accelerated solar testing is investigated by use of the aforementioned solutions and is found to be invalid for materials which degrade according to the photoreaction-diffusion model.

The four experimental through-tubes provided in the Experimental Gas Cooled Reactor will extend directly through the core of the reactor and penetrate both the upper and lower pressure vessel heads. Each tube is anchored in an upper head nozzle and the bottom end is allowed to slide in a lower head nozzle. This lower nozzle is basically a T'' section that provides bottom access to the through-tube and a side access for the piping which connects the throughtube to the experimenter's cell. Due to differential thermal expansion of the through- tubes relative to the reactor pressure vessel, vertical movement of the through- tube within the T'' section will be experienced. At the same time a horizontal thrust applied to each tube by thermal expansion of the piping to the experimental cell will result in metalto-metal contact between each tube and the lower T'' section. Tests were conducted on three types of bearing material proposed for use on the through-tubes and T'' sections to minimize galling which can be expected to occur. Stellite No. 12 has been demonstrated to be an adequate bearing material for the intended application. (auth)

A modified integrating sphere with a spectral measurement range from 0.5 to 10 microns is described. This integrating sphere can be used for in situ reflectance measurements of low temperature surfaces at vacuum conditions. The techniques employed in measuring the spectral reflectance of CO2 cryodeposits are discussed. Reflectance data for CO2 cryodeposits on stainless steel and Cat-a-Lac Black substrates are presented as a function of wavelength and cryodeposit thickness. The reflectance characteristics of the sphere's internal coating of NaCl are also presented.

Leptosphaeria narmari sp.nov. and L. korrae sp.nov., root and stolon parasites of various grasses in New South Wales, are described. Both grow readily in agar culture and can attack cereals and grasses in artificial inoculation tests. The generic position of the two species is discussed.