Activator choices

Fig. 1 Active choice of intravenous nicotine in experimentally naive squirrel monkeys, a Monkeys sat in chambers equipped with two levers and distinctly colored light stimuli above the levers. Completion of the response requirement (the ratio) on the active lever produced a brief 2-s presentation of a light stimulus and an intravenous injection of nicotine followed by a timeout (TO) period of 5-60 s. Completion of the ratio requirement on the inactive lever resulted in presentation of a brief 2-s light stimulus of a different color but no injection. The fixed-ratio (FR) response requirement was gradually increased over successive sessions from one to ten (FR 1-FR 10). b Mean percentage choice for responding on the active lever by monkeys when they were experimentally naive (first week under a FR 1 schedule) and when they had learned to self-administer nicotine under the FR 10, TO 60s schedule (first week under the FR 10 schedule). P < 0.01, compared to the first week of training. From Le FoU et al. (2007b)...

After 30 50 g of alcohol (consumed as 70 110 ml of cognac or whisky or 250 400 ml of wine) a biphasic action was observed. Some 30 45 min after the alcohol had been ingested, simpler mental activities such as reading and speed of simple reactions were often improved but there was no change in the more difficult tasks. Later on, i.e. more than 45 min after intake, performance was in general reduced, particularly for higher doses of alcohol and more complex activities (choice reaction times, wealth of word associations). 

Figure II-4-13 Block of tachycardia due to Drug P by hexamethonium is indicative of a sympathetic reflex that follows a decrease in BP due to a vasodilator (choice B). Reversal of bradycardia due to Drug Q by hexamethonium indicates a vagal reflex elicited by vasoconstriction (e.g., alpha activation) masking cardiac stimulation (e.g., beta activation) typical of norepinephrine (choice C). Tachycardia due to Drug R is unaffected by any antagonist, indicative of a beta activator (choice D). Reversal of tachycardia due to Drug S by hexamethonium indicates a sympathetic reflex masking a vagotomimetic action typical of a muscarinic activator (choice A) this is confirmed by the effect of atropine.

Figure II-4-5 The effects of Drug H are changed by treatment with either an alpha- or beta-blocker, so Drug H must have activity at both receptors (choices C, D, and E are ruled out). Reversal of a pressor effect can only occur if the drug has P2 activity (choice B is ruled out). Drug H is epinephrine.

Another key challenge is in making sure that all relevant greenhouse gas emissions are included, which may be an active choice but most often is merely... 

Even more puzzling is the fact that the stereoselectivity of this catalyst is affected by the nature of the cocatalyst/activator and the solvent. For polymerizations in toluene, the semicrystalline fraction in the polymer products was found to be significantly more abundant when using l/[HMe2NC6H5]+[B(C6F5)4] /Al(i-butyl)3 rather than 1/MAO. On the other hand, the semicrystalline fraction was completely absent, regardless of activator choice, for polymers prepared in moderately polar solvents such as bromobenzene or 1,2-dichlorobenzene. 

Dercon, Stefan. 1997. Wealth, Risk and Activity Choice Cattle in Western Tanzania. Oxford, UK Oxford University. 

BPMN makes use of external conditions on decision gateways to select the outgoing flow from a decision point. These decisions are modelled by the set L and assigned to specific flows by the function lab introduced in definition 1. In practice, decision points in a business process will have outcomes which depend on some inherent property of the task or on outside factors. The idea is that at a decision point an active choice is made, and then that choice results in a number of different possible outcomes. 

There has been, however, little focus on the point of view of the refugees themselves how do they decide whether to apply for resettlement Is resettlement something that simply happens in the process of their displacement, or are active choices involved How do resettled refugees react to the cumulative changes in their lives of displacement, a period (perhaps extended) with no solution, followed by a solution to their status and safety but new challenges of adjustment ... 

It is strictly for convenience that certain conventions have been adopted in the choice of a standard-state fugacity. These conventions, in turn, result from two important considerations (a) the necessity for an unambiguous thermodynamic treatment of noncondensable components in liquid solutions, and (b) the relation between activity coefficients given by the Gibbs-Duhem equation. The first of these considerations leads to a normalization for activity coefficients for nonoondensable components which is different from that used for condensable components, and the second leads to the definition and use of adjusted or pressure-independent activity coefficients. These considerations and their consequences are discussed in the following paragraphs. 

The results of the assessment are documented in an Environmental Impact Statement (EIS), which discusses the beneficial and adverse impacts considered to result from the activity. The report is one component of the information upon which the decision maker ultimately makes a choice. A final decision can be made with due regard being paid to the likely consequences of adopting a particular course of action, and where necessary by introducing appropriate monitoring programs. 

The wave function for the elechonic structure can in principle be any of the constructions employed in electronic structure theoiy. The prefened choice in this context is a wave funchons that can be classified as single and multi-configurational, and for the latter type only complete active space (CAS) wave... 

Empirically, the Dice coefficient has worked better than cosine similarity in retrieving actives and is the standard choice for use with the ap and tt descriptors. 

Another approach is spin-coupled valence bond theory, which divides the electrons into two sets core electrons, which are described by doubly occupied orthogonal orbitals, and active electrons, which occupy singly occupied non-orthogonal orbitals. Both types of orbital are expressed in the usual way as a linear combination of basis functions. The overall wavefunction is completed by two spin fimctions one that describes the coupling of the spins of the core electrons and one that deals with the active electrons. The choice of spin function for these active electrons is a key component of the theory [Gerratt ef al. 1997]. One of the distinctive features of this theory is that a considerable amount of chemically significant electronic correlation is incorporated into the wavefunction, giving an accuracy comparable to CASSCF. An additional benefit is that the orbitals tend to be... 

Activity of Mn02 depends on method of preparation and choice of solvent... 

First, the use of water limits the choice of Lewis-acid catalysts. The most active Lewis acids such as BFj, TiQ4 and AlClj react violently with water and cannot be used However, bivalent transition metal ions and trivalent lanthanide ions have proven to be active catalysts in aqueous solution for other organic reactions and are anticipated to be good candidates for the catalysis of aqueous Diels-Alder reactions. 

Once the molecules are aligned, a molecular field is computed on a grid of points in space around the molecule. This field must provide a description of how each molecule will tend to bind in the active site. Field descriptors typically consist of a sum of one or more spatial properties, such as steric factors, van der Waals parameters, or the electrostatic potential. The choice of grid points will also affect the quality of the final results. 

First the protected oligopeptide is coupled with polymer-bound nitrophenol by DCC. N"-Deblocking leads then to simultaneous cycliiation and detachment of the product from the polymer (M. Fridkin, 1965). Recent work indicates that high dilution in liquid-phase cycli-zation is only necessary, if the cyclization reaction is sterically hindered. Working at low temperatures and moderate dilution with moderately activated acid derivatives is the method of choice for the formation of macrocyclic lactams (R.F. Nutt, 1980). 

Many problems with MNDO involve cases where the NDO approximation electron-electron repulsion is most important. AMI is an improvement over MNDO, even though it uses the same basic approximation. It is generally the most accurate semi-empirical method in HyperChem and is the method of choice for most problems. Altering part of the theoretical framework (the function describing repulsion between atomic cores) and assigning new parameters improves the performance of AMI. It deals with hydrogen bonds properly, produces accurate predictions of activation barriers for many reactions, and predicts heats of formation of molecules with an error that is about 40 percent smaller than with MNDO. 

---