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A Porteous

Publications and source records attributed to A Porteous.

5 recordsLinked to original sources
PubMed2005

Why energy from waste incineration is an essential component of environmentally responsible waste management.

This paper outlines the key factors involved in adopting energy from waste incineration (EfWI) as part of a waste management strategy. Incineration means all forms of controlled direct combustion of waste. 'Emerging' technologies, such as gasification, are, in the author's view, 5 to 10 years from proven commercial application. The strict combustion regimen employed and the emissions therefrom are detailed. It is shown that EfWI merits consideration as an integral part of an environmentally responsible and sustainable waste management strategy, where suitable quantities of waste are available.

Air Pollutants↗
PubMed1991

Evaluation of methods for sampling, recovery, and enumeration of bacteria applied to the phylloplane.

Determining the fate and survival of genetically engineered microorganisms released into the environment requires the development and application of accurate and practical methods of detection and enumeration. Several experiments were performed to examine quantitative recovery methods that are commonly used or that have potential applications. In these experiments, Erwinia herbicola and Enterobacter cloacae were applied in greenhouses to Blue Lake bush beans (Phaseolus vulgaris) and Cayuse oats (Avena sativa). Sampling indicated that the variance in bacterial counts among leaves increased over time and that this increase caused an overestimation of the mean population size by bulk leaf samples relative to single leaf samples. An increase in the number of leaves in a bulk sample, above a minimum number, did not significantly reduce the variance between samples. Experiments evaluating recovery methods demonstrated that recovery of bacteria from leaves was significantly better with stomacher blending, than with blending, sonication, or washing and that the recovery efficiency was constant over a range of sample inoculum densities. Delayed processing of leaf samples, by storage in a freezer, did not significantly lower survival and recovery of microorganisms when storage was short term and leaves were not stored in buffer. The drop plate technique for enumeration of bacteria did not significantly differ from the spread plate method. Results of these sampling, recovery, and enumeration experiments indicate a need for increased development and standardization of methods used by researchers as there are significant differences among, and also important limitations to, some of the methods used.

Journal Article↗
PubMed1987

Measuring genetic stability in bacteria of potential use in genetic engineering.

Four commonly used conjugation techniques, colony cross streak (CCS), broth mating (BM), combined spread plate (CSP), and membrane filtration (MF), were compared with each other regarding reliability, sensitivity, and complexity in evaluating the transfer of conjugative plasmids. Five plasmids representing several incompatibility groups plus a variety of laboratory and environmental isolates were used as mating pairs. The suitability of each method was evaluated for use in a routine assessment of the genetic stability of genetically engineered microorganisms. By the CSP and MF techniques with laboratory strains such as Escherichia coli and Pseudomonas species as recipients, transconjugants were usually produced in 100% of the mating trials. However, when environmental strains isolated from plants and soil were used as recipients, transconjugants were detected in 100% of some crosses and in as little as 30% in other crosses depending on the plasmid and recipient used. In general, differences in the percentage of successful matings between the CSP and MF techniques compared with the BM and CCS techniques were not statistically significant at the P less than or equal to 0.05 level. Occasionally, certain mating pairs consistently produced transconjugants by CCS or BM but not by CSP or MF. Since any single conjugation mating technique is not completely reliable in detecting transconjugants, we have developed a combined mating technique which integrates the CCS, CSP, BM, and MF methods as a single procedure to assess the mobility of plasmid DNA of genetically engineered microorganisms.

Conjugation, Genetic↗
PubMedDate not supplied

Yes, I want to walk to the OR.

The health consumer of today is a more active participant in his or her health care. Although clients may require surgery, many of them do not consider themselves as being ill preoperatively. Health care professionals have a tendency to place the client in a dependent, ill role upon entering the health care facility. At this health care facility, clients are given the choice of either walking to the operating room, or going by stretcher. Studies found in the literature suggest that personal control is central to the reduction of clients' stress-related signs and symptoms. Nurses need to encourage client participation and assist the client to take control over those factors that are controllable. Utilizing King's (1981) conceptual framework, active client participation in mutual goal-setting, decision-making, and interactions to achieve the mutual goals in relation to health care is encouraged. All clients who attended the Preadmission Assessment Clinic were potential participants for this study. On the day of surgery, clients were asked by the nurse if they would prefer to walk to the operating room or go by stretcher. The majority of clients chose to walk to the operating room. The choice made by many of the clients is consistent with the findings in the literature stating that clients need a sense of control in what is often perceived as an uncontrollable environment.

Clinical Nursing Research↗