Galactosyltransferase activities during embryonic development of chick neural tissue

Galactosyltransferase specific activities in embryonic chick retina, optic tectum, and telencephalon were found to decline during embryonic development. Incorporation of galactose from nucleotide sugar into exogenously added glycoprotein acceptor was measured in the presence of excess of glycoprotein acceptor. This ensured that the specific activity measurements were reflections of tru enzyme specific activity rather than availability of acceptor. Moreover, we have shown that the decline in specific activity is not due to degradation of the nucleotide sugar, UDP-galactose, under our in vitro assay conditions. Enzymatic specific activity declined sharply with embryonic age for all tissues tested. This decline was not affected by the presence of 5-bromodeoxyuridine during in vitro culture of embryonic chick neural retina above that caused by the culturing alone. Galactosyltransferase activity was not found to be associated with the plasma membrane fraction from homogenized tissue but rather with the microsomal fraction. Thus, the changes in galactosyltransferase specific activity detected here do not reflect changes at the cell surface.     

Über den Stoffübergang zwischen Gasstrom und Erzstück im Hochofen

Berechnung des Partialdruckgefälles in der Gasgrenzschicht eines Erzkornes in einer Hochofenschüttsäule. Erfassung des Einflusses von Korngröße, Reduktionsgrad, Strömungsgeschwindigkeit und Reduktionsgas.     

Effectiveness measurements for a cooling film disrupted by a row of jets

The influence of cold air jet injection upon filmcooling of combustion chamber walls has been investigated by simulation. The experiments, in which a row of cold air jets is injected perpendicularly to the film cooled test chamber wall, show considerable decreases of the film cooling effectiveness downstream of the jet exit. The same behavior occurs in real combustion chambers of aircraft gas turbine engines. The tests are selected to represent combinations of geometries and flow variables (except the temperature ratios) which are pertinent to gas turbine combustor design. The present investigations cover effectiveness measurements for various combinations of the parameters: a) velocity ratio coolant film to mainstream b) velocity ratio jet to mainstream c) dimensionless distance between coolant film and jet exit d) spacing ratio e) ratio jet diameter to slot height f) ratio lip thickness to slot height.     

Microwave sensing from satellites

Microwave data from the ESMR sensor of the NIMBUS-6 satellite is used to obtain (i) rainfall rates during a tropical cyclone over the northern part of Western Australia, (ii) wind speed over the surface of the waters of the coastal regions of the southern part of Western Australia, and (iii) the microwave emissivity over the land surface of the southern part of Western Australia.     

Experimental and physical approaches on a novel semiconducting-ionic membrane fuel cell

Semiconducting-ionic membranes (SIMs) have exhibited significant superiority to replace the conventional ionic electrolytes in solid oxide fuel cells (SOFCs). One interesting phenomenon is that the SIMs can successfully avoid the underlying short-circuiting issue and power losses while bringing significantly enhanced power output. It is crucial to understand the physics in such devices as they show distinct electrochemical processes with conventional fuel cells. We first presented experimental studies of a SIM fuel cell based on a composite of semiconductor LiCo_0.8Fe_0.2O₂ (LCF) and ionic conductor Sm-doped CeO₂ (SDC), which achieved a remarkable power density of 1150 mW cm^?2 at 550 °C along with a high open circuit voltage (OCV) of 1.04 V. Then, for the first time we used a physical model via combining a semiconductor-ionic contact junction with a rectifying layer which blocks the electron leakage to describe such unique SIM device and excellent performance. Current and power are the most important characteristics for the device, by introducing the rectifying layer we described the SIM physical nature and new device process. This work presented a new view on advanced SIM SOFC science and technology from physics.     

Spray formation of middle distillates for autothermal reforming

The reforming of diesel and diesel-like fuels plays a central role in the development of fuel cell systems for on-board power supplies. The vaporization of the fuel via a spray formation and the subsequent mixture with water vapor and air determine the quality of the reforming process, as is shown in this paper. By using a high quality nozzle residual hydrocarbons were below 25 ppmV during the reforming of standard diesel. Through the use of a fuel injector in pulsed operation, the load range was able to be increased from 1:1.67 to 1:6. Spray pattern analyses were conducted using a high-speed camera. The formation of the spray pattern lasted 1.5–2 ms. The testing of a fast-closing magnetic valve manufactured by GSR Ventiltechnik was carried out on the autothermal reformer (ATR) type AH2. It exist not any direct influence of the pulsed operation on hydrogen production.     

Locomotion characteristics of dairy cows walking on pasture and the effect of artificial flooring systems on locomotion comfort

The locomotion comfort of dairy cows depends on the floor of the walking alleys. Optimal locomotion comfort is given when cows walk on pasture, allowing freedom from discomfort and pain and the expression of normal behavior. This study examined the characteristics of locomotion behavior on pasture (gold standard with optimal locomotion comfort) and compared it with behaviors of cows walking on mastic asphalt or solid rubber mats before and after a routine claw trimming session. Our hypotheses were (1) that gait variables were different on pasture versus mastic asphalt and on mastic asphalt versus rubber, and (2) that claw trimming had an effect on gait variables of cows walking on mastic asphalt. Twenty-four dairy cows kept in a tiestall facility were enrolled in this experimental trial. The pedogram was measured using 2 standalone 3-dimensional accelerometers (400 Hz), attached to the metatarsus of both hind limbs. The extracted pedogram variables included temporal events (kinematic outcome = gait cycle and stance-phase and swing-phase durations) and peaks (kinetic outcome = foot load, toe-off). The cows were further video-recorded to calculate walking speed and stride length. Locomotion score was performed on mastic asphalt to enroll only nonlame cows (locomotion score <3). For comparison between different floor types, repeated-measures ANOVA was performed with the cow as a subject variable, session time of measurement as within-subject variable, and flooring type as a fixed effect. Three separate analyses were performed: pasture versus mastic asphalt (analysis I), solid rubber versus mastic asphalt (analysis II), and the effect of claw trimming on the kinematic and kinetic variables on mastic asphalt (analysis III). All tested gait variables were significantly different between pasture and mastic asphalt floor. The optimal characteristics of locomotion comfort on pasture included shorter duration of gait cycle, longer stance-phase duration, shorter swing-phase duration, higher walking speed, longer stride length, and higher peaks of foot load and toe-off. However, gait variables of cows walking on rubber mats did not show any significant difference compared with the mastic asphalt floor; only stride length tended to be longer on rubber mats. In addition, the stance- and swing-phase durations significantly improved shortly after trimming. The left–right differences of the stance- and swing-phase durations tended to decrease after claw trimming when cows walked on asphalt floor. The results of this study show that solid rubber flooring does not result in significant improvement of the evaluated variables of locomotion comfort compared with mastic asphalt.