Bilateral Peter''s anomaly in an infant with 49,XXXXY syndrome

The discovery of canine achiasma and hemichiasma has been followed by the identification of human achiasma (four individuals, to date). See-saw nystagmus was present in all cases of achiasma (canine and human) and in one of two cases of canine hemichiasma studied. Human infants with see-saw nystagmus should be imaged for possible structural abnormalities of the optic chiasm.     

Open medial subtalar dislocation associated with fracture of the posterior process of the talus

A case of medial subtalar dislocation associated with fracture of the posterior process of the talus is described. Although this injury pattern is uncommon, it is important to recognize the associated fracture, as it involves a weightbearing articular surface. In this case, the flexor hallucis longus also prevented anatomic closed reduction necessitating open reduction and internal fixation.     

Effects of changes in response requirement and deprivation on the parameters of the matching law equation: New data and review.

The relation between response rate and reinforcement rate is described by the matching law equation. For an experiment in which there is just 1 explicit source of reinforcement, the equation has 2 parameters. The magnitude of 1 is equal to the response rate asymptote; the magnitude of the other is equal to the rate of reinforcement that maintains a one-half asymptotic response rate. This report describes experimental manipulations that affect these 2 parameters. Rats were trained on a series of variable-interval reinforcement schedules that provided reinforcement rates ranging from about 20 to 700 reinforcements per hour. The response was a lever press, and the reinforcer was water. In Exp I, the duration of the deprivation period was varied. Response rates maintained by the lower reinforcement rates showed the largest changes, and the parameter that is equal to the reinforcement rate for a one-half asymptotic response rate changed. In Exp II, the weight of the lever was varied. Response rates changed independently of reinforcement rate, and the parameter that is equal to the asymptotic response rate changed. In Exp III, manipulations from Exps I and II were combined. Results replicated those of Exps I and II. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The physical properties of alloys in the liquid and “mushy” states

Data on the physical properties of alloys at high temperatures are urgently needed for the mathematical modeling of high-temperature processes such as casting, welding, secondary refining, dip melting, spray forming, and metal powder production. Data are required for those properties which are involved in heat and fluid flow in high-temperature processes. Levitated drop methods have been adopted to measure the surface tensions, densities, and enthalpies of commercial alloys, and rapid, transient methods have been developed to measure thermal conductivities to avoid the problem of convection. The results obtained for the properties of commercial alloys for the liquid and mushy states are discussed.Paper presented at the Fourth International Workshop on Subsecond Thermophysics, June 27–29, 1995, Köln, Germany.     

The contamination of a major water supply by gulls (Larus sp.): A study of the problem and remedial action taken

In recent years one of the storage reservoirs supplying Loch Katrine water to Glasgow exhibited a serious deterioration in bacterial quality. This was associated with the winter nocturnal roosting habits of gulls (Larus sp.) on the reservoir. Investigations showed a significant correlation between the numbers of gulls roosting and the numbers of E. coli present in the water. Salmonellae organisms of identical serotypes were isolated from the gulls, from the untreated water and, on three occasions, from the treated water. Broadcasting species specific distress calls of Larus gulls proved to be an effective measure for discouraging gulls from roosting on the reservoir. The routine use of this bio-acoustic method of gull scaring reduced the bacteria in the water to numbers typical of an upland unpolluted reservoir.     

Techniques in the Study of Carbon Transfer in Ironmaking

In this paper two new approaches to the study of carburisation/decarburisation of iron are detailed. Firstly, a new experimental method focusing on understanding carbon transfer in a non‐traditional ironmaking process, and secondly, a new carbonaceous material (coke analogue) for use in coke laboratory investigations are detailed. The new experimental method was developed to assess the decarburising effects of high titania slags, typical of ironmaking with titaniferous ores or sands. Preliminary experiments found that carbon was being consumed from the metal as it passed through the slag. The coke analogue was developed to address material complexity and heterogeneity issues that often limit and mask important coke phenomena in laboratory studies. Preliminary dissolution experiments using the coke analogue to carburise iron showed that rate of dissolution was consistent with that published for both graphite and industrial coke.     

Quantum mechanics at the core of multi-scale simulations

Quantum mechancial forces at the core of multi-scale simulations, require a one-electron Hamiltonian approach whose solution provide electronic energies, forces, and properties for > 1,000 atoms fast enough that it can drive large scale molecular dynamics. Such a transfer-Hamiltonian is hoped to be as predictive as accurate, ab initio quantum chemistry for such systems. To design the Hamiltonian requires that, we investigate rigorous one-particle theories including density functional theory (DFT) and the recently proposed, correlated orbital potential (COP) approach that has been developed solely from wavefunction considerations. The latter insists upon exact, principal ionization potentials and electron affinities for a system, while DFT insists upon the exact density and the HOMO ionization. These two complementary approaches help identify the essential quantities that an exact one-particle theory of electronic structure requires. The intent, then, is to incorporate these into a simple approximation that can provide the accuracy required but at a speed four orders of magnitude faster than today’s DFT. The theory is presented and its neglect of diatomic differential overlap (NDDO) realization is illustrated for select systems.     

Avian diving, respiratory physiology and the marginal value theorem

We studied the effect of pressure up to 300 bar on the catalytic efficiency of subtilisin Carlsberg suspended in compressed propane, near-critical ethane, near-critical carbon dioxide and tert-amyl alcohol, at constant temperature and fixed enzyme hydration. Increasing pressure lowered the catalytic efficiency of the enzyme in all the solvents, resulting in positive activation volumes, delta V#. The delta V# values in compressed propane and in tert-amyl alcohol were similar and larger in magnitude than the value reported in the literature for the same reaction in an aqueous buffer, although within the range of typical delta V# values in aqueous media. In the near-critical fluids, the delta V# were much larger, e.g., an increase in pressure of only 200 bar causing a sixfold decrease in the catalytic efficiency of subtilisin in carbon dioxide. These data should reflect the proximity of ethane and carbon dioxide to the critical point, and the resulting condensation of solvent molecules about the solutes, yielding negative solute partial molar volumes.