An anaesthetic simulator program that runs on an IBM personal computer system has been developed. The program allows an operator to observe the uptake and distribution of the volatile anaesthetic agent halothane by a standard 75kg patient. The "patient's" breathing is assisted by a ventilator and the anaesthetic gas is supplied through a simulated circle breathing circuit. The most important component of a simulator is a mathematical model of the system being simulated. In this case a model of the uptake and distribution of the anaesthetic agent halothane by the human cardiovascular and respiratory systems was required. Such a model was developed by combining features of several existing non-linear multi-compartmental models and adapting the equations to allow them to be implemented on a digital computer. The simulator software that was developed allows an operator to adjust physical parameters such as fresh gas flow rate, halothane concentration, and breathing parameters from the keyboard of an IBM PC computer and observe the way various model parameters respond on a graphics screen. The speed of the simulation is adjustable. i.e., the state of the model can be repetitively calculated and displayed at 1, 10, or 60 second intervals. Model parameters can be displayed in bar graph or line-graph form and may also be dumped to a text file for use by other plotting programs. The software package developed should provide a useful teaching aid to understand the distribution of patient.

In recent years an increase of agile methodologies and their implementation in mainstream software engineering projects have been seen, but this implementation has reportedly changed agility in practice into a hybrid form of agility and more classic methodologies. With a lack of research regarding these hybrid methodologies this multiple case study empirically analyses the practice of methodologies from two different conglomerates and places the results in the Information Technology Management framework (ITMF) to answer the research question; How are hybrid agile methodologies enacted in practice in mature agile teams and why are they enacted in such a way? The result show that the organizations work agile within a waterfall framework, a hybrid form of requirement handling into agile development followed by waterfall testing. The hybrid methodologies are imposed by external factors such as the sales department and traditional economic reporting. This study acknowledges a need for a greater understanding of the engagement between external actors and software development.

published_or_final_version / Statistics / Doctoral / Doctor of Philosophy

Lu, Yao. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

A broad-based geochemical approach, including chemical and isotopic analyses of ground water, chemical analysis of aquifer materials, and laboratory water-rock experiments, was used to evaluate the origin and chemical evolution of ground water on La Palma, a volcanic island in the Canary Archipelago. Stable isotopes of oxygen, hydrogen, carbon and sulfur were successfully used to delineate recharge zones and identify solute sources. Laboratory study of water-rock interactions established the source of solutes and the nature of the chemical reactions that control ground-water chemistry. Most ground water on La Palma originates in a recharge zone that encircles the island from 500 to 1800 meters above sea level. Dry fallout and seaspray are minor sources of solutes, however, evaporative concentration during recharge may produce elevated chloride levels in some portions of the island. Laboratory water-rock experiments and ground-water analyses indicate that incongruent dissolution of aluminosilicate minerals is the dominant process of solute acquisition. The geochemical evolution of most waters is controlled by the availability of dissolved carbon dioxide gas. However, oxidation of pyrite enhances the reactivity of ground water in some portions of the island. Waters in the early phases of chemical evolution appear to be in equilibrium with a kaolinite alteration product, whereas more mineralized waters have compositions consistent with smectite equilibrium. Zones or compartments of ground-water flow were delineated by classifying sampling sites into geochemically distinct groups. Eight distinct zones of ground-water flow were identified using these criteria, including superimposed but hydrologically separate flow paths.

The popular use of in vitro systems for toxicity studies has increased dramatically over the past decade. Among the in vitro systems used, primary hepatocyte cultures are the most widely employed. However, in addition to being difficult to obtain and maintain in culture, the functional heterogeneity of liver is absent. Primary organ cultures of thin liver slices should overcome these limitations but the lack of a reproducible method for the rapid preparation of thin, consistent slices, combined with the difficulty in maintaining adult liver tissue in culture, has hindered their use for in vitro hepatotoxicity studies. Using a recently-developed tissue slicer, thin, consistent liver slices were prepared rapidly under minimally traumatic conditions. Subsequent culture of these slices in a novel dynamic organ culture system (DOCS) resulted in a maintenance of hepatocyte functional integrity. Slice adenosine triphosphate (ATP) and K⁺ content were maintained at in vivo levels, following an initial recovery period (2-4h) for up to 20h. Protein synthesis and secretion were linear for 20h and 16h respectively. Slices also synthesized glycogen between 4 and 12h in culture and were hormonally-responsive during the 20h culture period as demonstrated by a two-fold stimulation of glucose production by glucagon (10⁻⁷ M). Bromobenzene and allyl alcohol hepatotoxicity were studied in this system of organ culture. The slices retained their biotransformation ability for at least 6h based on maintenance of cytochrome P-450 content and O-deethylase activity. Either compound caused dose (.01-1.0 mM) and time (0-6h) dependent cytotoxicity as indicated by the loss of slice K⁺, inhibition of protein synthesis and leakage of lactate dehydrogenase (LDH). By 2h, a significant (p < 0.05) inhibition of protein synthesis was observed in allyl alcohol (.05 mM) treated slices. At 4h and 6h, significant loss of slice K('+), LDH, and inhibition of protein synthesis were evident in slices exposed to allyl alcohol (0.25 mM) or bromobenzene (0.5 mM). This toxicity was blocked by co-treatment with pyrazole (1.0 mM) or SKF 525-A (100 μM) in slices exposed to allyl alcohol or bromobenzene, respectively. Therefore, this system provides a new tool for the in vitro study of hepatotoxicity under conditions where hepatocellular functional integrity and biotransformation are maintained.

What are the proper aims and methods of philosophy? What is philosophy trying to accomplish, and how does it go about accomplishing it? A survey of the history of philosophy and current discussions regarding its aims and methods shows that philosophers radically disagree about the nature of philosophical inquiry. Part of the reason for this observation is that the aims and methods of philosophy are themselves philosophical topics. My task in meta-philosophy is to understand the nature of philosophy given that there is no distinct subject matter, and its aims and methods are subject to philosophical dispute; philosophy is an essentially divided discipline. Philosophers today and throughout history have supposed that philosophy is a scientific discipline; however, if my thesis is correct, philosophy cannot be a science. The first step is to appreciate the diversity of philosophical aims and methods; some aims and methods in philosophy directly contradict each other. Unlike science, which proceeds on the basis of a general universal methodology, philosophy is incapable of making scientific progress due to a radical methodological controversy at the very heart of the discipline. I recommend that, instead of attempting to merge with the aims and methods of science, philosophy should distinguish itself from science, and be understood as a different kind of discipline altogether. Once we reject the scientific meta-philosophical conception of philosophy, we can begin speculating and reconstructing the identity of philosophy from within philosophy itself.

published_or_final_version / Business Administration / Master / Master of Business Administration

published_or_final_version / Philosophy / Master / Master of Philosophy

published_or_final_version / Philosophy / Doctoral / Doctor of Philosophy