Early experiments with

Early experiments with pyridine-2,3-dicarboxylic mono- and bis-phenylhydrazides were unsuccessful (32JIC145), but later these were cyclized in acetic acid (66CPBIOIO) to give only the 7-phenylpyrido[2,3-[Pg.242]

Early experiments with zinc(II) (and aluminum(III)) naphthalocyanine were not very promising, although the lower sulfonic acids did show some PDT activity.268,269 The chromophore is of... 

Much of the previous research on the role of early olfactory experience on adult odor preferences has used the approach of cross-fostering young pups to a lactating dam of a different species (D Udine 1983). Thus, a shift in preference toward odor of the foster parent indicates that species-specific odors are learned via the early experience with the foster parent. Several important themes have emerged from this literature that shed light on the degree to which species preference is learned during early life. 

Solovieva and Minaev 2001). These data demonstrate that, for male Syrian hamsters, early experience with heterospecific odors eliminates species preference primarily by altering behavioral responses to conspecific odors. 

Taken together, this body of work demonstrates that adult behavioral responses to social odors are shaped by early olfactory experience. Indeed, heterospecific or artificial odor cues associated with the rearing environment acquire attractive properties that can last into adulthood in many rodent species. Furthermore, early experience with opposite-sex odors appears to be critical for the normal development of appropriate behavioral responses to sexual odors in mice and hamsters. Importantly, the behavioral plasticity observed using these different experimental approaches may all be mediated by a classical conditioning model of olfactory learning. The experience-dependent development of odor preference in rodents therefore provides a powerful model for understanding how the olfactory system recognizes and learns the salience of social odors, a function that is critical for the appropriate expression of reproductive behavior. 

Denenberg, V. H., Hudgens, G. A. and Zarrow, M. X. (1964) Mice Reared with Rats Modification of Behavior by Early Experience with Another Species. Science 143, 380-381. 

Lagerspetz, K. and Heino, T. (1970) Changes in social reactions resulting from early experience with another species. Psychological Reports 27, 255-262. 

Wendt and Fassel [2] reported early experiments with a tear-drop shaped inductively coupled plasma but later described the medium power l-3kW 18mm annular plasma now favoured in modern analytical instruments [3]. 

Interpretation of these early experiments with crude tissue preparations was greatly complicated by the presence of very active phosphatases (ATPases) which rapidly hydrolyzed any ATP which might have been formed. Ochoa suggested that the amount of Pj apparently esterified should be corrected for the measurable rate of ATP hydrolysis by the preparation. This gave P/O ratios approaching 3. Belitzer and Tsibakowa and Ochoa realized that phosphorylation must occur not only when the substrate is dehydrogenated. .. but also during... 

By the late 1940s methods of ionization counting had been developed for the estimation of 14C. Thin layers of suitably prepared material could be counted in windowless counters, with the emissions being detected by the probe in a flow of inert gas. Otherwise 14C-containing material could be combusted to 14C02 and this drawn over the probe. Neither method was very convenient to use and the instruments were costly. Early experiments with 14C were mainly performed in the U.S. (see below). 

The nature, or more precisely the structure, of a particular turbulent flame implied by these inequalities cannot be exactly established at this time. The reason is that values of <5L, Zk, A, or Z0 cannot be explicitly measured under a given flow condition or analytically estimated. Many of the early experiments with turbulent flames appear to have operated under the condition early theories that developed specified this condition in expressions for ST. The flow conditions under which <5L would indeed be less than Zk has been explored analytically in detail and will be discussed subsequently. 

Since the start of high school science courses, you have used the periodic table to help you investigate the composition and behaviour of the elements. Your early experiences with the periodic table were limited largely to the first 20 elements, because you could explain their electron structure without the concepts of orbitals and electron configurations. 

In mammals, early experience with social odors will have lasting effects on odor preferences. We have to distinguishji/w/ (attachment ofyoung... 

In addition to the circumstantial iji vivo evidence for fluorocitrate as the ultimate biochemical lesion we desired to demonstrate unambiguously that it was produced as a metabolite of 29-fluorostigmasterol. The toxicity of fluorocitrate and the resulting lethal accumulation of citrate in mouse, fly and cockroach tissues have been shown in early experiments with fluoroacetamide and fluoroacetate(24). However, to our knowledge, complete characterization of (2R,3R)-2-fluorocitrate as the lethal metabolite in vivo has not previously been reported. We thus prepared( ) [29- ]-29-fluorostigmasterol, [29- H]-29-Huorositosterol and [16- H]-16-fluorohexadec-9-enoic acid to enable isolation of [2-3H]-2-fluorocitrate from vivo incubations using Manduca sexta. 

Peterson, B.S., Leckman, J.R, Scahill L., Naftolin, E, Keefe, D., Char-est, N.J., King, R.A., Hardin, M.T., and Cohen, D.J., (1994), Steroid hormones and Tourette s syndrome early experience with antiandrogen therapy. / Clin Psychopharmacol 14 131—135. 

Chemical techniques of analysis deal with a very large number of atoms and yield averages over the sample. Once the concept of isotopes was accepted, a search for different isotopes of every element was pursued. The key to the success of this search was the development of a precision instrument that sampled the atoms one at a time. It had been known since the development of the cathode ray tube that positive ions were also produced, and early experiments with these particles revealed singly and doubly charged species of the atoms and molectrles that were contained in the tube. Sir J.J. Thomson observed in 1912 that when neon was the background gas, particles of mass ntrmber 20 and 22 were observed. Attempts to obtain pure samples of the two different atoms by fractionation techniques were unsuccessful, but in retrospect this was because they were both neon isotopes. 

In early experiments with polysulfone fibers, we included a hydrophilic prepolymer (precursor for the polyurethane employed) in the polysulfone system. It was... 

Early experiments with planar electrodes (Figure 16a) lead to car battery assemblies of radiating walls, where the reaction mixture is circulating in between the lamps (Figure 16b) [60-62]. 

Early Experience with the Phosphoric Aeld Fnel Cell (PAFC)... 

In presence of dissolved oxygen, photooxidation may also occur. Bowen and Williams (19) carried out some early experiments with benzene, some of its methyl derivatives, and certain other aromatic hydrocarbons in hexane solutions illuminated with light at 2537 A. They found low values for the quantum yields of fluorescence and of oxygen take-up the sum of these quantities being less than unity. At higher temperatures (>50°C.) chain propagation by a radical mechanism... 

Temperature Dependence. Early experiments with laboratory stills and a variable-speed steam compressor had shown that heat transfer and yield increased with temperature. The No. 5 compressor has a fixed speed and, since the specific volume of the steam decreases as temperature increases, the compressor was evidently starved for steam and operated in the unstable region when run at evaporator temperatures above 125° F. However, a trend toward increasing performance persisted,... 

Most of the early experiments with salvinorin A were performed by inhaling the vaporized crystal using the following technique. The salvinorin A was placed on the center of a piece of thick aluminum foil, which was heated from below with a butane micro-torch or "jet flame" lighten As the salvinorin A turned to a white vapor, the vapors were inhaled through a 15mm diameter glass tube. This technique requires careful performance. If one inhales before the crystal has been melted, the solid material wilt be taken into the mouth and will not produce the desired effects. However, if one waits more than a... 

It has been known for many years that the surface hydroxyl groups can be readily converted to OD simply by repeated exposure to D20. Early experiments with this type of exchange were used in order to manipulate vibrational modes to portions of the spectrum which were more transparent. Thus, for instance, isotopic substitution of D for H in surface silanol groups moves the fundamental stretching frequency from 3747 to 2750 cm 1. Peri (15) used this technique before computer subtraction was so readily available in order to determine the bond angle of the surface Sis-OH group. By recording... 

Bangladesh Rural Advancement Committee (BRAC) (2000) Combating a Deadly Menace Early Experiences with a Community-Based Arsenic Mitigation Project in Bangladesh, Research Monograph Series No. 16, BRAC, Dhaka. 

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