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51.
Pseudorabies virus (PRV) is a neurotropic swine alpha herpesvirus that characteristically invades the nervous system and replicates within synaptically-linked populations of neurons. The invasive characteristics and ability of this family of viruses to replicate in neurons of the central nervous system (CNS) have been exploited to map functionally related populations of neurons in a variety of systems. In this report, we examined the effects of strain and concentration on the ability of PRV to infect retinal ganglion cells and pass transneuronally through central visual circuits. We find that the ability of virulent (PRV-Becker) and attenuated (PRV-Bartha) strains of PRV to produce a productive infection of visual circuitry is directly dependent upon the infectious of the injected virus. Injections of at least 10(5) total plaque forming units produce 100% infectivity, whereas lower infectious doses substantially reduce the percentage of animals exhibiting productive infection via this route of inoculation. Furthermore, the virulent strain of PRV consistently infects a higher percentage of animals across a broader range of titers than attenuated virus. These data demonstrate that viral titer and strain are important variables that should be considered in the design of studies and interpretation of data derived from investigations employing this pathogen for circuit analysis. 相似文献
52.
53.
The rate of pheromone [(E)- and (Z)-11-tetradecenal] release from calling virginChoristoneura fumiferana females and synthetic lures was determined in both static and aerated atmospheres. In a static system ca. 2 ng/hr was recovered per female. Owing to the > 75% adsorption onto the females' bodies in static atmospheres, the actual release rate has to be corrected to roughly 9–27 ng/hr, depending on the percentage adsorbed. In the air-flow system, females were found to release between 4 and 20 ng/hr. On a 168 light-dark cycle, calling began 1–2 hr before lights-off and continued nonstop until lights-on. Pheromone was emitted throughout calling, while no pheromone was detected during the noncalling periods.Lepidoptera: Tortricidae.Published as Journal Article No. 10258 of the Michigan Agricultural Experiment Station. 相似文献
54.
H.C. Card 《Solid-state electronics》1977,20(12):971-976
The photovoltaic properties of MIS-Schottky barriers (metal-semiconductor contacts with insulating interfacial layers) are derived analytically from a consideration of the transport (tunneling) properties of majority and minority carriers. A simple expression is obtained for the dependence of the open circuit voltage on the interfacial parameters, which is in agreement with experimental results on Au-Si MIS-SB solar cells, for which the interfacial parameters are reasonably well known. The rather puzzling observation that the dark (majority-carrier) current is reduced by the interfacial layer, without at the same time decreasing the short circuit (minority-carrier) current is explained without having to assume any asymmetry in the tunneling probabilities for electrons and holes. The theoretical prediction for the maximum thickness of the interfacial layer (20 Å) for a constant short-circuit current and maximum conversion efficiency is also in good agreement with experiment. 相似文献
55.
Constantine Kaniklidis Leslie Mezei Richard Kittredge Albert C. E. Parker Hugh F. Cline Frank H. Nuessel Jr. James M. Beshers G. A. Clark John F. Hall Catherine Findler Nathan A. Greenberg T. J. Cartwright V. M. Du Feu Pauline Atherton Gerd Althoff John Rothman Joseph Raben Mimi Penchansky 《Language Resources and Evaluation》1979,13(4):311-333
56.
Donald E. Johnston Denise Kelly Pauline P. Dorrian 《Journal of the science of food and agriculture》1983,34(7):733-736
Differences in the extent of loss of pectic substances from potato (Solanum tuberosum L.) after boiling, steaming and pressure cooking were investigated. Losses were found to be significantly greater (P< 0.001) after boiling than after pressure cooking or steaming. The pectic substance content (g 100 g?1 dry matter) of potatoes (cv. Pentland Crown) was 2.98 for raw peeled tubers, 0.97 after boiling for 35 min, 1.22 after steaming for 35 min and 1.24 after pressure cooking at 103.4 kPa (15 psi) for 15 min. The roles of cooking time, cooking temperature and heat transfer medium are discussed. The effects of calcium sulphate (at levels typical of ‘hard’ and ‘soft’ water supplies) in the cooking water on losses of pectic substances from potato (Solanum tuberosum L.), carrot (Daucus carota L.), and swede (Brassica napus L. var. napobrassica Peterm.) after boiling and pressure cooking were also investigated. Water hardness did not influence losses during pressure cooking but samples boiled in hard water had decreased losses of pectic substances compared to those boiled in soft water. The increase in retention of pectic substances due to hard water was about 8 % for potatoes (cv. Pentland Dell), about 33 % for sliced carrots (cv. Berlicum, approved maintenance Perfecta) and about 23% for diced swedes (cv. Acme). The interaction of water hardness with cooking method was significant for potato (P< 0.05) and swede (P<0.001) and approaching significance (P=0.055) for carrot. 相似文献
57.
Radiation-induced charges in m.o.s. capacitors irradiated by protons can be effectively annealed out at a temperature of 300°C. An activation-energy analysis of the isochronal annealing results shows that the potential barrier created by the radiation-induced space charges in the oxide layer has an energy distribution ranging from 0.5 to 1.1 eV above the conduction band edge of silicon. 相似文献
58.
Pepinsky Harold B.; Pepinsky Pauline N.; Minor Frank J.; Robin Stanley S. 《Canadian Metallurgical Quarterly》1959,43(4):264
What is the relationship between management consistency of policy and team productivity? "A simulated small industrial plant was the setting for an experiment in which a team of Ss worked together on a manufacturing problem. Their assigned task was to produce different kinds of toys at a profit… . Twenty four-man teams were divided into ten consecutive team pairs, each member of a pair being subjected either to (a) a condition under which the team's expectations of management were contradicted by subsequent events or (b) a condition under which the team's expectations were confirmed. The hypothesis that team productivity would be greater under the confirmation condition was supported by the data. Some theoretical implications of the experiment were suggested." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
The optimum conditions for the removal of dissolved organic impurities from water using hydrogen peroxide (50%) followed by ultraviolet irradiation were investigated. The photochemically initiated hydroxyl radical (OH) oxidation reduced the total organic carbon (TOC) content of distilled water samples by about 88% and of tap water by 98%. Extraction with hexane of equal volumes of water samples before and after H2O2/u.v. treatment followed by gas chromatographic analysis of the concentrated extracts indicated that about 12% of the electron-capturing, residual organics remained after this treatment. These results support the conclusion drawn from total organic carbon analysis that this simple method yields water nearly free of organic impurities. 相似文献
60.
A still-air, wing fanning bioassay measured male pheromone response in the pink bollworm moth,Pectinophora gossypiella (Saunders). As pheromone concentration was increased, the duration of wing fanning increased while its latency decreased. Response duration was longest for the natural pheromone blend [44:56 (Z,E)- and (Z,Z)-7,11-hexadecadienyl acetates], although responses to 38% and 50%Z,E blends were not significantly briefer. Preexposure to pheromone had no effect on wing fanning in males retested after 24 hr. Wing fanning was highly correlated with upwind flight and other responses observed in a wind tunnel. Wing fanning duration provides a continuous measure of pheromone response and allows a large number of males to be tested in a short time; these two characteristics of the wingfanning assay are helpful for genetic analyses of male response. 相似文献