Qualitative Hypotheses Research Articles

Establishing Qualitative Hypotheses on the Influence of El Nifio On Metropolitan Adelaide Water Supply

ABSTRACT The question is raised whether El Nino, as a symptom of the Southern Oscillation, has an influence on Metropolitan Adelaide water supply. To answer this, four qualitative hypotheses have been established in this paper to indicate that there is an influence. The four hypotheses are described as follows. As Ninos and Australian droughts intensify, as represented by increasing negative intensity of the Southern Oscillation, there is a tendency for rainfall deficiency to increase over the catchments of the Mount Lofty Ranges supplying water to Metropolitan intake from the River Murray to supplement the supply deficiency of the Mount Lofty Range catchments. However, the Southern Oscillation may have an influence on River Murray flows into South Australia if such flows are not affected by regulation of up-stream storage. But for regulated River Murray flows into South Australia either at the Entitlement flow level or close to it, the influence of Ninos on such regulated flows may be masked by regulatio...

A critical comparison of the micronucleus yield from high and low LET irradiation of plateau-phase cell populations

Experimental data are presented which cast doubt on the usefulness of micronucleus assays as a quantitative measure of radiation damage. Synchronised (G 1) Syrian hamster fibroblasts (BHK21 C13) were exposed to doses of γ- or neutron radiation which yielded equivalent survival response. The cultures were examined at intervals during a 120-h post-irradiation incubation, for the appearance of micronuclei. Dose-response curves for the micronucleus yield constructed at a single sample time of 30 h were compared with those for the peak yield, irrespective of sampling time at each dose. When the total production of acentric fragments was compared with the peak yield of micronuclei no clear correlation could be seen. Qualitative hypotheses have been suggested to account for the various features of the data. The production and expression of micronuclei has been found to be a very complicated relationship and is a warning against too simplistic an interpretation of micronuclei data.

A new view on the origin of comets and other minor bodies

It is shown that the origin of the diverse structure of comets and other minor bodies cannot be explained by a single process. A qualitative dualistic hypothesis of the origin of these objects is developed. This hypothesis is based on information obtained by space missions and the discovery of a variety of evolutions associated with explosions and hot gaseous compressed interiors of giant planets. In addition, it is shown that different processes can lead to similar results, such as the formation on celestial bodies of craters by both volcanic and impact processes.

Excess enthalpies of aqueous solutions of mono- and oligo-saccharide at 25°

The heats of dilution in water of d-xylose, d-fructose, d-galactose, d-mannose, lactose, and raffinose have been determined calorimetrically at 25°. The calorimetric data, expressed in terms of excess enthalpy, lead to an evaluation of pair- and triplet-interaction coefficients. Osmotic data, where known, permit the analogous coefficients of the excess free energy to be obtained and thence those of the excess entropy. Analysis of the excess functions and comparison with spectroscopic properties permits some qualitative hypotheses to be formulated on the molecular interactions occurring in these solutions.

Performance theories for sentence coding: Some quantitative models

When memory is required, sentence reading time patterns are U-shaped over the phrases, with prolonged pauses at phrase boundaries. Qualitative hypotheses suggest why subjects engage in higher-level coding at phrase boundaries. Quantitative models account for how long subjects pause there. A two-process additive model accounts well for the data and better than nine other models. Beyond a base reading and motor time, the model includes an organization process for words in the current phrase and a contextual integration process for all preceding words in the sentence. This model is similar to serial processing models previously proposed for coding word lists, and an analysis of past research reveals coding similarities for sentences and word lists when memory demands are high.

Qualitative differences in concrete and formal operational tasks

Five concrete and five formal tasks were administered to 64 second-, fourth-,sixth, and eighth-grade subjects. A significant grade effect ( p ⩽ .01) but no significant sex effect or interaction was found. A cluster analysis indicated that four of the five formal tasks grouped together, two of the five concrete tasks grouped together, and the rest of the tasks remained isolated. These results were interpreted as supporting both Piaget's qualitative hypothesis and the structural characteristics of the concrete and formal stages.

Molecular orbital theory of the electronic structure of organic compounds. I. Substituent effects and dipole moments.

A recent approximate self-consistent molecular orbital theory (complete neglect of differential overlap or CNDO) is used to calculate charge distributions and electronic dipole moments of a series of simple organic molecules. The nuclear coordinates are chosen to correspond to a standard geometrical model. The calculated dipole moments are in reasonable agreement with experimental values in most cases and reproduce many of the observed trends. The associated charge distributions of dipolar molecules show widespread alternation of polarity in both saturated and unsaturated systems. These results suggest that charge alternation may be an intrinsic property of all inductive and mesomeric electronic displacements. ne of the long-term aims of quantum chemistry 0 is to provide a critical quantitative background for simple theories of electron distribution in large molecules. Most theoretical discussions of the role of electronic structure in organic chemistry are at present based either on qualitative arguments (such as the study of resonance structures) with no clear foundation in quantum mechanics, or on postulated relationships between charge distribution and various physical and chemical properties (reactivities, acidities, nmr chemical shifts, etc.), few of which can be subjected to direct test. If quantum mechanical calculations are to lead to independent methods of studying such phenomena, they ought to satisfy the following general conditions. (1) The methods must be simple enough to permit application to moderately large molecules without excessive computational effort. Quite accurate wave functions now exist for many diatomic and small polyatomic molecules, but it is unlikely that comparable functions will be readily available in the near future for the molecules of everyday interest to the organic chemist. To be accessible, a quantum mechanical theory has to be approximate. (2) Even though approximations have to be introduced, these should not be so severe that they eliminate any of the primary physical forces determining structure. For example, the relative stabilities of electrons in different energy levels, the directional character of the bonding capacity of atomic orbitals, and the electrostatic repulsion between electrons are all gross features with major chemical consequences and they should all be retained in a realistic treatment. (3) In order to be useful as an independent study, the approximate wave functions should be formulated in an unbiased manner, so that no preconceived ideas derived from conventional qualitative discussions are built in implicitly. For example, a critical theoretical study of the localization of a two-electron bond orbital ought to be based on a quantum mechanical theory which makes no reference to electron-pair bonds in its basis. Molecular orbital theories satisfy this type of condition insofar as each electron is treated as being free to move anywhere in the molecular framework. (4) The theory should be developed in such a way that the results can be interpreted in detail and used to support or discount qualitative hypotheses. For example, it is useful if the electronic charge distribution calculated from a wave function can be easily and realistically divided into contributions on individual atoms

Trial Spacing in Instrumental Running

Trial spacing was studied over 120 acquisition trials and 20 each of extinction, reacquisition, and re-extinction, using five intertrial intervals from 40 sec. to 120 min. in between four daily trials. Throughout acquisition, performance of the 120-min. group increased throughout the course of a daily block, while the others first increased, then decreased. Spontaneous regression persisted throughout acquisition. Extinction performance was not systematically related to trial spacing, and no evidence for spontaneous recovery was found. Changes in measured spatial variability in the alley indexed learning but did not differentiate trial spacing effects. The results generally failed to confirm qualitative hypotheses about trial spacing derived from statistical learning theory.

Deposition Temperature and Compositional Dependence of Negative Anisotropy in Nickel-Iron Films

An investigation of the deposition temperature (200° to 350°C) and compositional (80% to 87% Ni) dependence of negative anisotropy (K−) in nickel-iron films has been made. The results indicate that the number of K− regions is zero below a critical temperature which depends on composition and increases with increasing temperature; the more negative the magnetostriction λ (λ<0 for % Ni>83), the lower the critical temperature. The following qualitative hypothesis is suggested for the origin of K− regions: It is known that deposited metal films have a real surface area much larger than the macroscopic area of the deposit. Thus the films are actually porous and mass diffusion between adjacent crystallites occurs in order to lower surface energy at the expense of strain energy. If the mass diffusion were anisotropic, for example, by depending on the direction of M, then anisotropic strain would be generated. The resulting anisotropic strain coupled to ± magnetostriction would then generate local K± (or K∓ since the sign of the strain has not been specified) regions.

Solar corpuscles responsible for geomagnetic disturbances

A qualitative hypothesis is given that attributes recurrent “M-region” geomagnetic disturbances to the arrival at the earth of solar corpuscles that have been gathered into beams by the deflecting action of coronal-region fields, presumably magnetic, associated with centers of heightened solar activity. The hypothesis identifies the source of solar corpuscles that produces M-region magnetic disturbances with “quiet areas” of the solar surface. A related hypothesis associates non-recurrent magnetic storms, the greatest ones, with a different solar corpuscular source, found in the active region itself.

Solar corpuscles responsible for geomagnetic disturbances.

view Abstract Citations (1) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Solar corpuscles responsible for geomagnetic disturbances. Pecker, Jean-Claude ; Roberts, Walter Orr Abstract Some years ago C. W. Allen presented all extensive analysis of geomagnetic storms, and offered suggestions for their explanation in terms of streams of corpuscles originating in the sun.' We offer a qualitative hypothesis, that incorporates Allen's suggestions and identifies the solar source of corpuscular emission responsible both for recurrent and non-recurrent geomagnetic disturbances. We postulate two different types of solar sources of such particles as follows: (a) Small jets of corpuscles, distributed in a fine network all over the surface of the sun, and presumably associated with chromospheric spicules or photospheric granules. These jets, in the absence of deflecting solar magnetic fields, would send radial streams of corpuscles in all directions; the streams would be present at all times, regardless of the state of solar activity. In the presence of deflecting magnetic fields from active centers, and the general magnetic field of the sun, the corpuscles are deflected to form the streams responsible for the recurrent "M-region" geomagnetic disturbances. (b) Irregular streams of ions associated with active regions, and probably most intense at the time of solar flares. Not all active centers have such streams present at all times, and there is probably also a large dispersion of particle velocities and stream energies for this type of corpuscular stream. We present evidence from a study of geomagnetic disturbances in 1952-53 to support the hypothesis of the formation of recurrent magnetic storms by particle streams of the first type. In particular we find evidence that above certain active regions there is a "cone of avoidance" with low particle density. The center of the cone reaches earth three days later. We also show that there is some evidence that at the edges of the cone-of-avoidance the deficiency of corpuscles is compensated by regions with an excess particle density. The hypothesis is in accord with the explanation we gave earlier for the formation of the K component of the white light corona,' here associated with the solar-terrestrial corpuscular beams. The hypothesis suggests that daily coronagraphic observation of the white light corona may prove of great value for prediction of the times of occurrence of geomagnetic storms and associated phenomena. This work was supported by the Air Force Cambridge Research Center, Geophysical Research Directorate, Air Research and Development Command. 5.M. N. 104, 53, 5944. 2.Roberts, W. 0., R. Grenchik, and D. E. Billings, A. f. 58, 225, 5953. High Altitude Observatory, Boulder, Colo. Publication: The Astronomical Journal Pub Date: October 1954 DOI: 10.1086/107040 Bibcode: 1954AJ.....59..330P full text sources ADS |