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Sportfishing creel census pilot study
The sportfishing creel census project was originated to obtain information relating to the use of the Corpus Christi Bay area for sportfishing, the amount of fish caught and other environmental information relating to the total productivity cycles of the bay system. The Census is to be conducted during the summer months of June, July and August 1974 and the pilot study was made during August 1973. The total catch will be used in a current project to assess carbon, nitrogen, phosporous input and output to the bay system.March 15, 1974To The Lower Nueces River Water Supply DistrictMarine Scienc
Quark-gluon vertex in arbitrary kinematics
We compute the quark-gluon vertex in quenched lattice QCD, in the Landau
gauge using an off-shell mean-field O(a)-improved fermion action. The complete
vertex is computed in two specific kinematical limits, while the Dirac-vector
part is computed for arbitrary kinematics. We find a nontrivial and rich tensor
structure, including a substantial infrared enhancement of the interaction
strength regardless of kinematics.Comment: 6 pages, 8 figures, talk by JIS at QCD Down Under, Adelaide, 10-19
March 200
A review of the literature for the development of a process path.
The costs of injury are of obvious importance for the
purposes of priority setting in prevention planning by
policy makers and stakeholders in general. The economic
costs of injury and death have been the focus of
considerable international attention in recent years.
Localisation of these studies and their methods to the
South African injury context, however, remains largely
underdeveloped. The costing of fatal and non-fatal
injuries in South Africa consists of a number of initiatives
undertaken by various segments of both the
public and private sectors. This article will review the
existing literature devoted to the estimation of costs in
various sectors of the South African morbidity and
mortality contexts, with a view to illustrating the manner
in which this information informed both provisional
processes and structure for the implementation of a
nationwide South African injury costing project. The
literature is examined across three primary dimensions:
the precise object of the study, the method
employed in the costing of that object, and the sample
coverage of the method.
The findings of the review indicated a number of significant
entry-points for the development of a local
South African costing model. A preponderance of
direct medical costing, significantly discrepant expenditure
figures between the public and private health care
systems and blurring of distinct costing concepts are
problematic themes throughout the review of the literature.
This article illustrates the manner in which the
identification of the problems and promises of these
existing costing studies informed the sites, injury types
and methodology selected for development and implementation
of a National South African Injury
Costing Project
Exactly Conservative Integrators
Traditional numerical discretizations of conservative systems generically
yield an artificial secular drift of any nonlinear invariants. In this work we
present an explicit nontraditional algorithm that exactly conserves these
invariants. We illustrate the general method by applying it to the three-wave
truncation of the Euler equations, the Lotka--Volterra predator--prey model,
and the Kepler problem. This method is discussed in the context of symplectic
(phase space conserving) integration methods as well as nonsymplectic
conservative methods. We comment on the application of our method to general
conservative systems.Comment: 30 pages, postscript (1.3MB). Submitted to SIAM J. Sci. Comput
Electrochemical Evaluation of LaNi_(5–x)Ge_x Metal Hydride Alloys
We report a detailed evaluation of Ge-substituted LaNi_5 for electrochemical application as a negative electrode in alkaline rechargeable cells. Alloys with small substitutions of Ge for Ni show operating pressures, chargeability, cyclic lifetime, and kinetics for hydrogen absorption and desorption all superior to those found in many other substituted LaNi_5 alloys. These improved properties were achieved with a minimal reduction in hydrogen storage capacity
Electrochemical Studies on LaNi5–xSnx Metal Hydride Alloys
Electrochemical studies were performed on LaNi5–xSnx with 0 <= x <= 0.5. We measured the effect of the Sn substituent on the kinetics of charge-transfer and diffusion during hydrogen absorption and desorption, and the cyclic lifetimes of LaNi5–-xSnx electrodes in 250 mAh laboratory test cells. We report beneficial effects of making small substitutions of Sn for Ni in LaNi5 on the performance of the metal hydride alloy anode in terms of cyclic lifetime, capacity, and kinetics. The optimal concentration of Sn in LaNi5–xSnx alloys for negative electrodes in alkaline rechargeable secondary cells was found to lie in the range 0.25 <= x <= 0.3
Electrochemical Properties of LaNi5–xGex Alloys in Ni-MH Batteries
Electrochemical studies were performed on LaNi5–xGex metal hydride alloys with 0 <= x <= 0.5. We carried out single-electrode studies to understand the effects of the Ge substituent on the hydrogen absorption characteristics, the electrochemical capacity, and the electrochemical kinetics of hydrogen absorption and desorption. The electrochemical characteristics of the Ge-substituted alloys are compared to those of the Sn-substituted alloys reported earlier. LaNi5–xGex alloys show compositional trends similar to LaNi5–xSnx alloys, but unlike the Sn-substituted alloys, Ge-substituted alloys continue to exhibit facile kinetics for hydrogen absorption/desorption at high solute concentrations. Cycle lives of LaNi5–xGex electrodes were measured in 300 mAh laboratory test cells and were found to be superior to the Sn-substituted LaNi5 and comparable to a Mm(Ni,Co,Mn,Al)5 alloy. The optimum Ge content for LaNi5–xGex metal hydride alloys in alkaline rechargeable cells is in the range 0.4 <= x <= 0.5
Assessing the outcome of orthognathic surgery by three-dimensional soft tissue analysis
Studies of orthognathic surgery often focus on pre-surgical versus post-surgical changes in facial shape. In contrast, this study provides an innovative comparison between post-surgical and control shape. Forty orthognathic surgery patients were included, who underwent three different types of surgical correction: Le Fort I maxillary advancement, bilateral sagittal split mandibular advancement, and bimaxillary advancement surgery. Control facial images were captured from volunteers from local communities in Glasgow, with patterns of age, sex, and ethnic background that matched those of the surgical patients. Facial models were fitted and Procrustes registration and principal components analysis used to allow quantitative analysis, including the comparison of group mean shape and mean asymmetry. The primary characteristic of the difference in shape was found to be residual mandibular prognathism in the group of female patients who underwent Le Fort I maxillary advancement. Individual cases were assessed against this type of shape difference, using a quantitative scale to aid clinical audit. Analysis of the combined surgical groups provided strong evidence that surgery reduces asymmetry in some parts of the face such as the upper lip region. No evidence was found that mean asymmetry in post-surgical patients is greater than that in controls
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