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E C Parsons

Publications and source records attributed to E C Parsons.

10 recordsLinked to original sources
PubMed2001

Parasites from Indo-Pacific hump-backed dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong.

Between 1993 and 1998, 28 Indo-Pacific hump-backed dolphins (Sousa chinensis) and 32 finless porpoises (Neophocaena phocoenoides) stranded in Hong Kong territorial waters were examined postmortem for parasites. The nematode Halocercus pingi was discovered in the lungs of one hump-backed dolphin and in 10 finless porpoises, typically within abscesses or granulomata, and they were frequently accompanied by a catarrhal exudate and lesions characteristic of pneumonia. Seven of the 10 finless porpoises were calves with substantial lungworm infections, and three were neonates with visible fetal folds and umbilical remnants, suggesting that H pingi is transferred to the neonate before birth or during lactation. Electron micrographs of H pingi should allow the nematode to be identified by other researchers. An ectoparasitic stalked barnacle (Xenobalanus globicipitis) was recovered from a finless porpoise, the first time that this species of barnacle has been recorded in Hong Kong's territorial waters.

Animals↗
PubMed2000

Post-mortem investigations on stranded dolphins and porpoises from Hong Kong waters.

Stranded cetaceans reported from the territorial waters of Hong Kong during the period May 1993 to March 1998 were examined to establish factors that may have contributed to their death. During the current study, 28 Indo-Pacific hump-backed dolphins (Sousa chinensis), 32 finless porpoises (Neophocaena phocaenoides), and four bottlenose dolphins (Tursiops truncatus) were necropsied. Bacteria (15 species) were isolated from nine animals. Of these bacteria, 47% were of possible fecal origin reflecting the high level of sewage contamination in Hong Kong's waters. One finless porpoise displayed wounds caused by a shark attack, and two female finless porpoises presented prolapsed uteri. At least 10 finless porpoises showed evidence of moderate to heavy lungworm infections (Halocercus pingi), and this appears to have been a factor contributing to death in at least six animals. Evidence suggesting blunt traumatic injury (probably caused by boat collisions) was found in six cetaceans (three finless porpoises and three hump-backed dolphins). Signs of fishery-related mortality were detected in at least nine animals (six hump-backed dolphins, two finless porpoises, and one bottlenose dolphin). Of these two human-caused mortality types, pre-existing disease or bacterial infection were detected in 29% of cases. Results indicate that human factors may have played a significant role in the death of at least 15 animals (32% of hump-backed dolphins, 15% of finless porpoises, and 25% of bottlenose dolphins).

Animals↗
PubMed1998

Trace metal pollution in Hong Kong: implications for the health of Hong Kong's Indo-Pacific hump-backed dolphins (Sousa chinensis).

The territorial waters of Hong Kong are highly contaminated with anthropogenic pollutants, including trace metals. Hong Kong's population of Indo-Pacific hump-backed dolphins (Sousa chinensis) inhabits an area where a high volume of sewage waste discharge and the close proximity of contaminated mud pits mean a considerable potential for trace metal contamination. Trace metal concentrations in the muscle tissue of fish caught from areas of high dolphin abundance are notable. However, in order to gauge the amount of trace metal consumed by dolphins, whole fish must be analysed. Whole fish from areas of high dolphin abundance have considerably higher trace metal loads than muscle tissue alone. Considering the consumption of prey items by dolphins, a daily intake of trace metals was estimated as As, 410-518; Cd, 34-44; Co, 4-5; Cr, 40-50; Cu, 44-56; Hg, 51-66; Mo, 22-27; Ni, 19-24; Pb, 320-403; Se, 99-125 and Zn, 388-490 (microgram kg-1 body wt. per day). Concentrations of arsenic, chromium, lead, molybdenum and nickel in dolphin tissues were an order of magnitude lower than in prey items, suggesting these elements may be excreted by this species. Mercury concentrations in dolphin tissues were, however, an order of magnitude higher than in prey items and could be considered potentially health threatening (max: 906 micrograms kg-1 dry wt.). Hong Kong's Indo-Pacific hump-backed dolphin population has a high dietary intake of trace metals which may, especially in the case of mercury, be a cause for concern.

Animals↗
PubMed1997

Building a successful risk-based competency assessment model.

The requirement to verify and ensure the competency of staff members to perform their assigned duties is here to stay. This article describes a model for decision making about competency assessment frequency. Implementation of the model should be accompanied by a systematic review of learning needs and performance improvement data. Education sessions designed to address identified learning needs or to support performance improvement activities should occur before or concurrent with competency assessment. The result is a cost-effective, efficient use of resources to accomplish the goal of ongoing assessment and improvement of staff competency. When staff member competency improves, the likelihood of a positive patient outcome increases. Our model provides a structured, defensible mechanism to link competency assessment with improvements in patient care quality.

Clinical Competence↗
PubMed1997

Single-and dual-energy CT with monochromatic synchrotron x-rays.

We explored the potential for clinical research of computed tomography (CT) with monochromatic x-rays using the preclinical multiple energy computed tomography (MECT) system at the National Synchrotron Light Source. MECT has a fixed, horizontal fan beam with a subject apparatus rotating about a vertical axis; it will be used for imaging the human head and neck. Two CdWO4-photodiode array detectors with different spatial resolutions were used. A 10.5 cm diameter acrylic phantom was imaged with MECT at 43 keV and with a conventional CT (CCT) at 80 kVp: spatial resolution approximately equal to 6.5 line pairs (lp)/cm for both; slice height, 2.6 mm for MECT against 3.0 mm for CCT; surface dose, 3.1 cGy for MECT against 2.0 cGy for CCT. The resultant image noise was 1.5 HU for MECT against 3 HU for CCT. Computer simulations of the same images with more precisely matched spatial resolution, slice height and dose indicated an image-noise ratio of 1.4:1.0 for CCT against MECT. A 13.5 cm diameter acrylic phantom imaged with MECT at approximately 0.1 keV above the iodine K edge and with CCT showed, for a 240 micrograms I ml-1 solution, an image contrast of 26 HU for MECT and 13 and 9 HU for the 80 and 100 kVp CCT, respectively. The corresponding numbers from computer simulation of the same images were 26, 12, and 9 HU, respectively. MECT's potential for use in clinical research is discussed.

Acrylates↗
PubMedDate not supplied

The relationship of problems in biomedical MRI to the study of porous media.

The NMR methods that are used to characterize inanimate porous media measure relaxation times and related phenomena and material transport, fluid displacement and flow. Biological tissues are comprised of multiple small, fluid-filled compartments, such as cells, that restrict the movement of the bulk solvent water and whose constituents influence water proton relaxation times via numerous interactions with macromolecular surfaces. Several of the methods and concepts that have been developed in one field of application are also of great value in the other, and it may be expected that technical developments that have been spurred by biomedical applications of MR imaging will be used in the continuing study of porous media. Some recent specific studies from our laboratory include the development of multiple quantum coherence methods for studies of ordered water in anisotropic macromolecular assemblies, studies of the degree of restriction of water diffusion in cellular systems, multiple selective inversion imaging to depict the ratios of proton pool sizes and rates of magnetization transfer between proton populations, and diffusion tensor imaging to depict tissue anisotropies. These illustrate how approaches to obtain structural information from biological media are also relevant to porous media. For example, the recent development of oscillating gradient spin echo techniques (OGSE), an approach that extends our ability to resolve apparent diffusion changes over different time scales in tissues, has also been used to compute surface to volume measurements in assemblies of pores. Each of the new methods can be adapted to provide spatially resolved quantitative measurements of properties of interest, and these can be efficiently acquired with good accuracy using fast imaging methods such as echo planar imaging. The community of NMR scientists focused on applications to porous media should remain in close communication with those who use MRI to study problems in biomedicine, to their mutual benefits.

Animals↗