Biomedical subjects

Don Harris

Publications and source records attributed to Don Harris.

5 recordsLinked to original sources

PubMed2006

Characterization of self-assembled supramolecular [Ga4L6] host-guest complexes by electrospray ionization mass spectrometry.

Self-assembled supramolecular host-guest complexes have been characterized by electrospray ionization mass spectrometry. The spectra obtained by use of a Q-TOF instrument equipped with a Z-spray ion source show primarily the 3- and 4- charge states of the assemblies. The assemblies have the general formula [guest subset Ga4L6]11- where L represents the chelating bidentate catechol ligand 1,5-bis(2',3'-dihydroxy-benzamido)naphthalene and guests are tetramethyl ammonium (Me4N+), tetraethyl ammonium (Et4N+), tetra-n-propyl ammonium (Pr4N+) and decamethylcobaltocenium (Cp*2Co+) cations. For the first time, the mass spectrum of the empty assembly [Ga4L6]12- is reported. This article also reports that provided the electrospray ion source is capable of preserving noncovalent interactions, it is possible to observe host-guest complexes containing both weak binding guests as well as sterically demanding guests in the mass spectra. The present data suggest that electrospray mass spectrometry is a powerful tool for characterization of supramolecular host-guest complexes.

Crystallization↗

PubMed2006

Ripples in a pond: an open system model of the evolution of safety culture.

The development of an effective safety culture is essential to promote safe operations. Previous studies have either identified the characteristics of effective safety culture analytically, inferring them from signs and symbols derived from working practices, or have restricted the study of the development of safety culture to workers within an organisation. This paper describes a large-scale survey-based study in which the factors influencing the evolution of safety culture are identified empirically and, drawing upon open systems theory, are also extended beyond the bounds of the organisation. Three major determinants of safety culture are identified: safety concerns, influences and actions. Sub-components within each of these categories are also identified and the relationship between them is hypothesised.

Adult↗

PubMed2006

Pilot error and its relationship with higher organizational levels: HFACS analysis of 523 accidents.

INTRODUCTION: Based on Reason's model of human error, the Human Factors Analysis and Classification System (HFACS) was developed as an analytical framework for the investigation of the role of human error in aviation accidents. However, there is little empirical work that formally describes numerically the relationship between the levels and components in the model (the organizational structures, psychological precursors of errors, and actual errors). METHOD: This research analyzed 523 accidents in the Republic of China (ROC) Air Force between 1978 and 2002 through the application of the HFACS framework. RESULTS: The results revealed several key relationships between errors at the operational level and organizational inadequacies at both the immediately adjacent level (preconditions for unsafe acts) and higher levels in the organization (unsafe supervision and organizational influences). CONCLUSIONS: This research lends support to Reason's model that suggests that active failures are promoted by latent conditions in the organization. Fallible decisions in upper command levels were found to directly affect supervisory practices, thereby creating preconditions for unsafe acts, and hence indirectly impaired performance of pilots, leading to accidents. The HFACS framework was proven to be a useful tool for guiding accident investigations and developing accident prevention strategies.

Accidents, Aviation↗

PubMed2005

The development of a multidimensional scale to evaluate motor vehicle dynamic qualities.

Advances in motor vehicle engineering will allow greater refinement of the dynamic qualities of passenger cars in the near future. This paper describes the development and initial validation of a reliable and valid multidimensional scale to assess these parameters based upon a technique previously developed to evaluate aircraft handling qualities. The scaling methodology developed emphasizes the interaction between the vehicle's dynamic behaviour and the category of vehicle (e.g. sports car, executive saloon). This three-part study describes the initial extraction and the subsequent verification of the scale dimensions from an analysis of the opinions of circa 500 drivers, followed by an evaluation of the sensitivity and diagnosticity of the scale to distinguish between the road behaviour exhibited by vehicle types. The results suggest that the scale shows both content and construct validity, being able to distinguish both between broad categories of vehicle and different models of vehicle within a particular category in a consistent and meaningful manner.

Adolescent↗

PubMed2005

Aeronautical decision making: instructor-pilot evaluation of five mnemonic methods.

INTRODUCTION: The ability to make good decisions is a critical component of pilot proficiency. Results of recent research suggest that aeronautical decision making (ADM) can be improved by training. The purposes of this research are to identify the best ADM mnemonic-based methods for training military pilots in decision making in tactical environments. METHODS: There were 60 instructor pilots in the Republic of China Air Force Academy who evaluated the suitability of 5 different ADM methods including SHOR (Stimuli, Hypotheses, Options, Response); PASS (Problem identification, Acquire information, Survey strategy, Select strategy); FOR-DEC (Facts, Options, Risks & Benefits, Decision, Execution, Check); SOAR (Situation, Options, Act, Repeat); and DESIDE (Detect, Estimate, Set safety objectives, Identify, Do, Evaluate). Each was evaluated for six different types of decisions: go/no go; recognition-primed; response selection; resource management; non-diagnostic procedural; and creative problem-solving. RESULTS: The instructor-pilots regarded the SHOR method as the best for time-limited and critical, urgent situations, while they preferred DESIDE for knowledge-based decisions that needed more comprehensive consideration and were less time limited. DISCUSSION: To optimize training effectiveness, it is necessary to provide instruction based around both the SHOR and DESIDE decision-making mnemonic methods to provide comprehensive instruction for coping with all situations in the demanding military aviation environment.

Accidents, Aviation↗