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M Ulbrich

Publications and source records attributed to M Ulbrich.

47 records · Page 3Linked to original sources

Comparison of lunar with terrestrial and meteoritic rocks.

This note examines critically recent attempts to identify or closely correlate lunar surface samples-on the basis of alpha-scattering analysis-with terrestrial igneous rocks (basalts) or with eucrite meteorites. Basalts show considerable variety; but all have chemical characteristics inherited from terrestrial mantle rock melted under a limited range of terrestrial pressure-temperature conditions. What is characteristic is not so much the content of any particular element or oxide-e.g., SiO(2) 47-52 per cent-but rather a complete chemical pattern in which such ratios as Fe/Mg and Ca/(Na + K) show consistent relationships to Si content. These are the chemical criteria that might be useful in comparing terrestrial basalt with extraterrestrial rocks. Basalts also have distinctive mineralogical and textural characteristics; and if a lunar or meteoritic rock is to be identified as basalt it must possess these, too.Turkevich's analysis of alpha-scattering data for lunar samples (Surveyor V) show significant departure from basaltic composition: Very high (Ca + K)/Na associated with distinctly high Fe/Mg. In basalts relatively high (Ca + K)/Na-in no case approaching the reported lunar values-tends to be associated with Fe/Mg values lower than average. The same "lunar" pattern of high (Ca + K)/Na and Fe/Mg appears in recorded analyses of eucrite meteorites. In the lunar samples, Ti is notably higher than in basalts, and even more so than in eucrites. If eucrites are of lunar origin their Ti values are, so far, a real anomaly.

Journal Article↗

[Urea utilization of growing lambs. 2. Growth experiments].

In two growth experiments with 30 lambs per group the influence of urea (1-2% of the ration) and straw (20-30% of the ration) on the performance was studied under conditions of intensive fattening. The content of native crude protein in the rations varied between 10.1 and 18.4% of the DM. In experiment 1 the lambs of the two groups which received mixed feed for fattening lambs without urea on average consumed with 1.02 and 1.11 kg DM resp., 696 and 757 EFUcattle resp. and 173 and 189 g crude protein resp. per animal and day. The groups with wheat or barley and urea consumed 1.06 and 0.96 kg DM resp., 714 and 627 EFUcattle resp. and 209 and 155 g crude protein resp. Their weight gain of 247 g/animal and day was 24% and that of 230 g resp. 26% higher than that in the control groups without urea. The lowest dry matter intake (0.91 and 0.82 kg resp.) was shown by the animals of the groups which received wheat or barley without urea. In the second experiment the control group achieved an average daily weight gain of 327 g at an expenditure of 2.24 kEFUcattle/kg weight gain. Despite a partly higher dry matter intake, the daily EFUcattle intake was between 12.2 and 24.5% lower in the straw groups and energy expenditure increased between 12.0 and 27.8%. Urea supplements of between 1 and 2% improved dry matter, EFUcattle and crude protein intake and thus weight gain.

Animal Feed↗

[Influence of emulsifiers and fat mixtures on the digestibility and sedimentation of fatty acids in calves].

In a digestibility experiment with 4 X 4 calves the animals received 100 g mixture for calves, 50 g dried green fodder and either 656 g dried whole milk and 164 g dried skim milk (VM) or 656 g dried whole milk and 164 g added fat. The added fat consisted of a mixture of tallow and lard in a 1:1 ratio plus 10% emulgator ES 20 (FE) or 8% ES 20 and 2% soybean lecithin (FL) or 25% lard, 25% tallow, 40% rape/sunflower oil with 10% ES 20 (FO). The apparent digestibility of the fat amounted to 91% in group VM and in groups FE/FL/FO to 66/70/67% resp. The composition of fatty acids and the use of an unsuitable charge of dried skim milk are considered to be the causes of the low apparent digestibility. The apparent digestibility of the fatty acids decreased with their growing chain length. The higher digestibility of the unsaturated fatty acids is largely caused by changes due to bacterial activity in these fatty acids in the intestines and by the influence of metabolically changed faecal fat. The combination of the synthetic emulgator with lecithin did not improve fat digestion but diminished the total fat content in the blood.

Animal Feed↗

[Urea utilization in growing lambs. 7. NPN- and pure protein-N-utilization at various ages].

The utilization quota of NPN and pure feed protein for body protein synthesis was calculated on the basis of N balance experiments with 15N labelled urea with the help of model concepts of a 3-pool model and its mathematical usage. In lambs weighing 13 kg, the efficiency of amino acid and nucleic acid synthesis in the non-amino acid N pool was 64%. This results in a total utilization quota for NPN and pure protein in the ration of 40% and 60%, resp. Lambs weighing 27 kg showed an efficiency in amino acid and nucleic acid synthesis in the non-AA N pool of 77% and in the AA N pool of 60%. The total utilization quota of NPN was 47% and that of pure protein 56%. The pure protein in the ration was thus about twice as well utilized for total protein synthesis and for protein synthesis for crude protein retention as the NPN compounds in the ration.

Aging↗

[Influence of energy concentration and source on the utilization of feed protein and NPN in lambs. 2. 15N balance and utilization of pure protein and NPN].

In an experiment 12 lambs of the merino species were divided into 4 groups. The variants HE received 740 or 718 EFU cattle/kg DM and the variants NE 689 or 671 EFU cattle/kg DM. The different energy concentrations resulted from differentiated quotas of dried sugar beet chips and wheat starch supplements. Within the variants, sub-variants with (HESZ, NESZ) or without (HES, NES) sugar supplements were formed. Due to varied DM intake, the average energy intake in all groups was 42 EFU cattle/kg LW0.75. N balance experiments using 15N-labelled urea were carried out, and 15N accumulation of N excretion was projected to a steady state. The partial utilization of pure protein and NPN in the ration was ascertained with the help of a 3-pool compartment model of N utilization in ruminants. In the non-amino acid N pool HE utilized 84% of NPN and NE 77% for the synthesis of amino and nucleic acids. The efficiency of protein synthesis in the amino acid N-pool were in HESZ 64%, HES 70%, NESZ 70% and NES 73%, resp. The total utilization of NPN is the sum of the partial utilization in the two pools, whereas the total utilization of pure protein is calculated from the true digestibility and the efficiency of the utilization in the AA-N pool. The total utilization of NPN for the synthesis of protein for the protein pool amounted to 40/35/41/33% and that of pure protein to 54/51/49/50%. Energy intake being identical, energy concentration did not have an influence on the utilization of pure protein and NPN, whereas NPN utilization was better in rations containing sugar. The pure protein in the ration was by 19 ... 52% better utilized than NPN.

Animals↗

An arm phantom: a digital simulation system for testing sphygmomanometers.

An arm phantom for testing non-invasive blood pressure measuring instruments under reproducible and real conditions has been developed. Signal records, recorded on patients and validated by a reference method, are played into the instruments to be tested using a combination of an electro-pneumatic and an electro-acoustic converter. For each of 90 patients a database contains records of at least three different kinds of signal: cuff pressure oscillations, Korotkoff sounds (except in neonates) and cuff pressure. As the inflation and deflation rate varies between different sphygmomanometers the control and synchronization of the signal output are ensured as a function of the instantaneous cuff pressure, measured continuously by the system. A segmented output procedure synchronizes the data flow during the test procedure. The records of blood pressure signals are separated in different signal groups, containing only one pressure oscillation and Korotkoff sound respectively, whereas the instantaneous cuff pressure determines the signal group to be selected. Suitable interfaces to the sphygmomanometers under test consist of two specifically developed signal converters, an electro-pneumatic converter and an electro-acoustic converter. The system generates both cuff pressure oscillations and Korotkoff sounds from real data earlier recorded on human subjects. It allows any inflation and deflation rate of the cuff pressure to be applied, considers the variability of the pulse rate occurring in the same data record and finally it allows the superposition of artefacts. The arm phantom can replace clinical trials. The possibility of testing the limits of the performance of sphygmomanometers has been considerably extended.

Arm↗