Non-destructive characterisation of fine grained samples: assessment of insitu micro-XRD of primitive meteorite matrix

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Evaluation of a bereavement training programme for volunteers at a Community Centre

Student Number : 0204770E - MEd research report - School of Education - Faculty of HumanitiesThe present study investigates a bereavement training programme with a group of volunteer lay counsellors. In South Africa, the number of orphans resulting from an increase in parental deaths from natural causes, such as AIDS and nonnatural causes, for example violence, is increasing rapidly. The increasing number of bereaved children is creating a demand for professional support services that cannot be met by the present number of trained professionals. To address this imbalance, the training of lay counsellors is proposed. It is thus relevant to train those who are willing to help with the necessary knowledge and skills in a bereavement training programme. The present study involves ten volunteers from a Community Centre. Qualitative research methods are employed to analyse the data that is gained from the preand post-training responses to the interviews and Case Examples. Content analysis is used to elucidate the themes that emerge from the collected data. The results of the present study indicate that perceptual and developmental changes have occurred within the volunteers following the training programme, however, it is evident that further training is necessary because of the limited ability that the volunteers demonstrate in practically transferring the knowledge to new cases. In terms of this finding it is clear that factors such as language, age, educational level and personal experiences of death are important criteria to consider in the selection of volunteers for a bereavement training programme. Furthermore, traditional African perspectives of death, cultural differences and HIV/AIDS awareness need to be incorporated into future bereavement training programmes. In terms of the outcomes of the study, a positive outcome is the revision of the Bereavement Programme for children, taking cognisance of cultural sensitiveness, to make it more applicable within the local context. The results of the study also highlight the limitations and implications of the present research, which are discussed and recommendations for future research are made

A Procedure for Testing Cored Ice Under Uniaxial Tension

A procedure is described for testing cored ice specimens under uniaxial tension. The procedure incorporates an end-capping system described by Cole and others (1985), two carpeted Synthane end caps, and extensometers mounted directly on the ice. Use of the procedure has resulted in a successful test rate of 75

Assimilatory sulfur metabolism in marine microorganisms

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution December 1980The reductive assimilation of sulfate into cellular organic sulfur compounds was studied in aerobic marine bacteria, with emphasis on the relationship between sulfur metabolism and protein synthesis. The goal of the study was to develop and apply a method for the quantitative assay of total bacterial protein synthesis in aerobic ocean waters. The study consisted of four parts: (1) The sulfate transport systems of two nutritionally different marine bacteria, Pseudomonas halodurans and Alteromonas luteo-violaceus, were characterized to provide information on environmental regulation of sulfate transport capacity. In common with terrestrial bacteria, the transport systems of both marine bacteria exhibit (a) size-selective competitive inhibition of sulfate uptake by sulfate analogs, (b) requirements for energy coupling,and (c) derepression of transport capacity as a result of sulfur starvation. Features which are unique to the marine bacteria include (a) a ten-fold lower affinity for sulfate (half-saturation constant ~200 μm), (b) derepression of transport capacity when grown with methionine as the sole source of sulfur, and (c) an inability to accumulate inorganic sulfate in excess of growth requirements. The different characteristics of the sulfate transport systems of the marine bacteria relative to terrestrial microorganisms are consistent with the saturating concentration of sulfate that is always present in their environment. Substantial differences also exist between the two marine bacteria, notably in the effect of thiosulfate on sulfate uptake. P. halodurans transports thiosulfate with a ten-fold higher affinity than sulfate. Sulfate and thiosulfate are mutually competitive inhibitors of transport, and the half-saturating concentration of thiosulfate for uptake also produces half-maximal inhibition of sulfate transport. Sulfate and thiosulfate transport systems both respond similarly to all inibitors. These facts implicate a common carrier for the two compounds. In contrast, sulfate transport in A. luteo-violaceus is relatively insensitive to thiosulfate. The effect of the suIfhydryl reagent pHMB is similarly much less pronounced than in P. halodurans. These and other differences indicate that the sulfate transport system of A. luteo-violaceus is unique among microorganisms. (2) Growth experiments with P. halodurans and A. luteo-violaceus were carried out over a range of nutritional regimes. Biomass parameters (cell counts, bulk protein, particulate carbon and nitrogen), total uptake of radioactive sulfate, and the distribution of sulfur in major biochemical components (low molecular weight [L.M.W.], alcohol soluble protein, lipid, hot TCA soluble material, and residue protein) were monitored to determine the variability in cellular composition as a function of the environment. Special emphasis was placed on the quantitative relationship between incorporation of sulfur into protein and bulk protein synthesis and conditions which might alter the sulfur content of protein. It was found that sulfur metabolism is restricted predominantly to the production and utilization of protein precursors. The protein synthesis inhibitor chloramphenicol caused an immediate halt to both bulk protein synthesis and sulfur incorporation into protein, accompanied by a rapid swelling of L.M.W. organic sulfur pools, in both bacteria. Incorporation of exogenous sulfur into protein was rapid due to the very small size of the L.M.W. pool. No significant deviation from the ratio of protein-S:bulk protein determined for unperturbed exponential growth was observed as a function of carbon limitation, nitrogen limitation, treatment with chloramphenicol, or during lag and stationary phases. However, the concentration of sulfate in the growth medium exerted a strong influence on the sulfur content of both whole cells and isolated protein. At concentrations less than 500 μM (P. halodurans) or 100 μM (A. luteo-violaceus) the weight % S in protein was proportional to the silate concentration in the medium. Since the sulfate concentration is invariably high in seawater (25mM), data from sulfur-limited growth were not included in the analysis of compositional variability. Under all the conditions examined, the incorporation of sulfur into protein provided the best measurement of protein synthesis and cell growth, with a very low coefficient of variation for the protein-S:bulk protein ratio (less than 16%). The mean true weight % S in protein, 1.07 (P. halodurans) and 0.92 (A. luteoviolaceus) agrees well with the 1.1% predicted from analyses of sequenced proteins. (3) The method used for the analysis of sulfur incorporation into protein was tested with mixed natural populations of marine bacteria in enrichment culture and 13 isolates from the Sargasso Sea to establish the variability of the protein-S:bulk protein ratio among marine bacteria. The mean true weight % S in protein, 1.09, and the operational weight % S in protein, 0.93, have coefficients of variation of 13.1 and 15.1%, respectively. The values are similar to those obtained with the two marine bacteria studied in detail and to that predicted from protein composition studies. Therefore sulfur incorporation into protein measures protein synthesis in marine bacteria within a small degree of error. (4) The method was applied to unenriched natural populations of marine bacteria in waters of the continental shelf, slope, and Sargasso Sea. Time-course incorporation measurements revealed along lag period at the shelf and slope stations, whereas incorporation of sulfur into protein began immediately in the Sargasso Sea. However, long term incubations confirmed that the potential for bacterial protein synthesis decreases in an off-shore transect. These observations were confirmed by simultaneous incorporation studies using labeled ammonia, phosphate, and organic carbon compounds. The potential protein synthesis measured in the unenriched samples provides evidence suggesting that bacterial biomass may be an important contributor to marine food webs.Gracious financial support provided by the National Science Foundation (grants OCE77-12172, OCE79-19178, and OCE79-19264) and the Education Department of W.H.O.I. are appreciate

Synthesis and Characterization of Diamond-like Carbon Thin Films for Biomedical Applications

Diamond-like carbon (DLC) thin films were produced by pulsed laser deposition (PLD) on silicon, fused silica, and silicon nitride substrates. The films produced were either undoped, made using a pure graphite target, or doped, using multi-component targets made from a combination of graphite and silicon, silicon nitride, titanium dioxide, or silicon monoxide. These films were evaluated for their potential use in biomedical applications, including coatings for artificial joints, heart stents, and bronchoscopes. The films were characterized by Raman spectroscopy, atomic force microscopy, ball-on-flat tribometry, contact angle measurements, and spectrophotometry. Film thickness was determined by optical profilometry. Film adhesion was checked by soaking the films in simulated body fluid (SBF) and monitoring the quality of the film surface at varying time intervals using an optical microscope. DLC coatings were produced with a root mean square surface roughness of less than 1 nm and a 0.08 lubricated coefficient of friction. Contact angles of water on the undoped films varied with deposition conditions, ranging from 65 to 88 degrees. Contact angles as low as 25 degrees were achieved by incorporating silicon monoxide dopant. DLC coatings were produced on fused silica having high transparency and showing no delamination after forty-three weeks of immersion in SBF. These results indicate that these films have potential as biomedical coatings

Putting Lab into Lecture

Engineering classes at any level are separated into two separate components, lecture and lab. Often these two classes have little to no direct relationship, being taught by two different instructors with different objectives. Students struggle to see the relationship between the theory from lecture and the applications in lab. To bridge the gap, lab must be brought into the lecture. Students must experience the theory by building, measuring, and exploring the concepts. Instructors can bring these experiences into the classroom by breaking labs up into smaller activities that are closely related to the theory. This is not to say that larger labs should be eliminated but augmented with these minilabs embedded in the class. Example applications from electrical engineering courses are to be shared and discussion of how to apply this in various courses

Time Management Experiences Among Adult Learners in an Online Undergraduate Degree Program

The purpose of this case study was to discover the time management experiences of adult learners in an online undergraduate degree program at a mid-sized, Midwestern private university. The theory guiding this study was Tourangbam’s (2011) time equity theory as it emphasized the connection between time management and both productivity and life satisfaction. Data was collected through online (Zoom) interviews, a virtual (Zoom) focus group, and photovoice (Wang & Burris, 1992) exercise in which participants took photographs that represented their priorities, obligations, and time-wasters, which were the three categories of time management identified in time equity theory (Tourangbam, 2011). Data was analyzed qualitatively, allowing emergent categories to form from the raw data. Data from the three types of sources were synthesized, and multi-layered member-checking was used to increase the dependability of the study. The results of this study demonstrated common experiences, behaviors, and understandings of priorities, obligations, and time-wasters among the participants. The participants consistently used time-management strategies identified in existing literature (Macan et al., 1990), as well as self-regulation behaviors (Bandura, 1991). However, participants did not make the distinction between priorities and obligations described by Tourangbam (2011) and used these terms interchangeably. All participants identified social media as a time-waster and admitted to struggling to minimize time-wasters. Participants described their places of study as typically chaotic, high-traffic areas with frequent interruptions, but also identified supportive family as a primary factor in their academic success

The Prepared Flute: A Survey of its History, Techniques, and Repertoire

Beginning with Varese’s Density 21.5 in 1936, composers have been experimenting with extended techniques to expand the flute’s range of sound. In an attempt to increase the timbral possibilities of the instrument, contemporary composers are writing for the prepared flute: adding objects on or inside the flute, or subtracting parts of the flute to alter its sound. is the first written document to focus on the prepared flute. Deborah Fethers, in her major project discussing contemporary flute design in 2005, mentions the use of prepared flute by Michael Pestel, and states that “to my knowledge the only use of such ‘preparation’ of a flute is by Pestel” (Fethers). My research shows that there are, in fact, numerous other examples of composers’ use of preparations when writing for the flute, and this document serves to compile those examples. With compositions for prepared flute written as early as the 1980s, the flute community is in need of a detailed account of the pieces available, how to tackle the technical intricacies, and a reference for composers to consult. As the above quote indicates, most musicians in the flute community are unaware that the prepared flute genre exists, let alone know the major players involved in this area. Limitations of this study include the difficulty to obtain copies of all pieces written for prepared flute because many are either hard to find or unpublished. Correspondence from the composers is deficient, due in part to language and location barriers or lack of response. This document presents the history of the prepared flute through the examination of ten pieces, and discusses objects commonly used to prepare the instrument. In addition, this project involved commissioning a new work for prepared flute and prepared piano, a combination lacking in current repertoire. The preparations for the flute provide new realms of sound possibilities for the instrument, offer new avenues for composing unpredictable music, and inspire new chamber music that includes prepared flute. With greater awareness of prepared flute, the author hopes that more flutists will become aware of the possibilities, composers will be inspired to add to the idiom, and audiences will be inspired by the music that results. Also included in this document are tables that list repertoire and preparations specific to each piece, and two appendixes that provide listening possibilities and locations to purchase the compositions mentioned in this document. Finally, my website (www.staceyleerussell.com) includes a section dedicated to new pieces for prepared flute, experimentations, recordings, and helpful tips