A study of the understanding of knowledge and learning of a cohort of mature age students

In 2005 the authors began a longitudinal research project to explore the factors that influence student success in the Master of Engineering Practice program which was offered for the first time in Semester 2, 2004. This distance education program enables experienced Engineering Technologists to use their workplace learning to gain a qualification at the Professional Engineer level. This research was initiated because the admission of some students into the program is based on the recognition of their prior workplace learning. Cantwell and Scevak (2004) highlighted the problems that students may encounter when they gain entry to a university on this basis. To explore this issue four previously validated questionnaires were used to gather data on: student approaches to learning, their epistemological beliefs, learning style preferences, and strategic flexibility. This paper reports on a preliminary analysis of the data gathered from the students who enrolled in the program during the period 2005-2009. In the longer term, when the sample size has grown and more students have graduated, the data will be analysed to explore the relationship between the measured factors and success at university

The immunomodulatory properties of helminth-derived products on dendritic cell maturation and function

Parasitic worms and molecules derived from them drive Th2/Treg immune responses in mammalian hosts and have powerful anti-inflammatory properties which are shown to have therapeutic effects on inflammatory diseases. Using products derived from the helminth parasites Fasciola hepatica and Ascaris lumbricoides we investigated the mechanism by which these responses are induced. Dendritic cells (DC’s) play a crucial role in linking the innate to adaptive arms of the immune system and directing the subsequent immune responses. Here, we report that Fasciola hepatica tegumental antigens (FhTeg) can suppress DC maturation and function. While FhTeg alone did not induce cytokine production or cell surface marker expression on DCs, it can maintain the DCs in an immature state, suppressing their function to Toll-Like-Receptor (TLR) stimulation and impairing the subsequent development of adaptive immunity. Furthermore, we selected recombinant forms of two major F. hepatica secreted molecules, the protease cathepsin L (rFhCL1) and anti-oxidant, sigma class glutathione S-transferase (rFhGST-si), to examine their interactions with DCs. Despite enzymatic and functional differences between these antigens they both induced IL-6, IL-12p40 and chemokine secretion from DCs in a TLR4 dependent manner. While neither helminth enzyme induced Th2/Treg immune responses both could instruct DCs that suppress IL-17 secretion in vivo. This study also demonstrates that another helminth-derived heterogeneous extract, Ascaris lumbricoides pseudocoelomic fluid (AlPCF), induced partial maturated of DCs as characterised by the increased production of IL-6, IL-12p40 and MIP-2. These DCs were capable of inducing Th2 responses. Overall the data suggests that helminth parasites secrete multiple molecules each possessing a unique mechanism of modulation, which can either suppress inflammatory Th1/Th17 responses or induce/permit the uninhibited development of modified Th2 responses

Particle image velocimetry in molten plastic

Injection molding is a standard manufacturing process for plastic parts. The most important process step, mold filling, involves unsteady nonisothermal flow of a non-Newtonian molten plastic. Mold-filling flow largely determines molecular orientation within the final part and thereby influences final part properties. This article describes techniques for successfully applying particle image velocimetry (PIV) to molten plastic flow during injection molding. The primary experimental challenges include the following: engineering optical access to the molten plastic flow at elevated temperatures (230–245°C) and pressures (∼20 MPa), finding particles that survive the thermal-mechanical environment that melts the plastic, and developing experimental and data-reduction techniques that allow multiple imperfect planar PIV measurements to be combined. Here, a custom optical-access mold allowed mold center-plane PIV to be performed in molten polystyrene. Simple statistical assessments of the velocimetry data and scaled residuals of the continuity equation suggest that the PIV can be conducted in molten plastics with an uncertainty of ±2%. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics EngineersPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83457/1/21881_ftp.pd

Do Perceptions of Ballot Secrecy Influence Turnout? Results from a Field Experiment

Although the secret ballot has long been secured as a legal matter in the United States, formal secrecy protections are not equivalent to convincing citizens that they may vote privately and without fear of reprisal. We present survey evidence that those who have not previously voted are particularly likely to voice doubts about the secrecy of the voting process. We then report results from a field experiment where we provided registered voters with information about ballot secrecy protections prior to the 2010 general election. We find that these letters increased turnout for registered citizens without records of previous turnout, but did not appear to influence the behavior of citizens who had previously voted. These results suggest that although the secret ballot is a long-standing institution in the United States, providing basic information about ballot secrecy can affect the decision to participate to an important degree.

Introgressive Hybridization and the Evolution of Lake-Adapted Catostomid Fishes.

Hybridization has been identified as a significant factor in the evolution of plants as groups of interbreeding species retain their phenotypic integrity despite gene exchange among forms. Recent studies have identified similar interactions in animals; however, the role of hybridization in the evolution of animals has been contested. Here we examine patterns of gene flow among four species of catostomid fishes from the Klamath and Rogue rivers using molecular and morphological traits. Catostomus rimiculus from the Rogue and Klamath basins represent a monophyletic group for nuclear and morphological traits; however, the Klamath form shares mtDNA lineages with other Klamath Basin species (C. snyderi, Chasmistes brevirostris, Deltistes luxatus). Within other Klamath Basin taxa, D. luxatus was largely fixed for alternate nuclear alleles relative to C. rimiculus, while Ch. brevirostris and C. snyderi exhibited a mixture of these alleles. Deltistes luxatus was the only Klamath Basin species that exhibited consistent covariation of nuclear and mitochondrial traits and was the primary source of mismatched mtDNA in Ch. brevirostris and C. snyderi, suggesting asymmetrical introgression into the latter species. In Upper Klamath Lake, D. luxatus spawning was more likely to overlap spatially and temporally with C. snyderi and Ch. brevirostris than either of those two with each other. The latter two species could not be distinguished with any molecular markers but were morphologically diagnosable in Upper Klamath Lake, where they were largely spatially and temporally segregated during spawning. We examine parallel evolution and syngameon hypotheses and conclude that observed patterns are most easily explained by introgressive hybridization among Klamath Basin catostomids

Four-dimensional laser induced fluorescence study of the structure of molecular mixing in turbulent flows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77075/1/AIAA-1994-820-515.pd

Laser machined macro and micro structures on glass for enhanced light trapping in solar cells

In order to increase the efficiency of solar cell modules it is necessary to make the optimum use of light incident upon them. Much research has been done on improving light absorption through front surface texturisation and light trapping schemes. Laser light is commonly used in industry for various applications including marking and texturisation. By controlling laser parameters, it is possible to tailor macro and micro structures in most materials. The CO2 laser used in this investigation emits radiation at 10.6 μm with the ability to pulse in the micro-second range. The laser was used to ablate grooved textures in the fused quartz material, used in this study as the light trapping medium, following which an analysis of the effects of the laser parameters on the texture geometry and surface morphology was performed through a combination of cross sectioning and scanning electron microscopy. Transmission through the textured glass was improved for most samples after acid etching. The light trapping effects of the best performing textures were analysed by investigating the effects on a silicon solar cell’s performance at varying angles of incidence. Results indicated a significant increase in light trapping when light was incident at acute angles. For an angle of incidence of 10◦ a relative increase in efficiency of up to 51 % was observed

High Reynolds-Number Assessment of a Multifractal Subgrid-Scale Model

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77107/1/AIAA-2002-2961-570.pd

Development of a GFP‐based biosensor for detecting the bioavailability and biodegradation of polychlorinated biphenyls (PCBs)

Two whole‐cell biosensors were constructed to detect the in situ biodegradation of polychlorinated biphenyl by chromosomal insertion of a mini‐Tn5‐Kmr‐Pm::gfp[mut3]‐T0‐T1 construct into P. fluorescens. In vitro tests showed that the expression of the Pm promoter depended on the growth phase of the biosensors and the concentration of chemical inducers; chlorinated benzoic acid derivatives. A linear relationship between the fluorescent intensity and the log10 concentration of the inducer was observed. One biosensor (F113L::1180gfp) had the ability to degrade PCBs to relevant chlorobenzoic acid derivatives and to induce expression of Gfp. The second biosensor (F113gfp), which cannot degrade PCBs, shows fluorescence after induction by chloro‐benzoic acid derivatives. By using these two biosensors, PCB degradation could be detected in vitro and in soil. Gfp pagrindo biosensorių tobulinimas polichlorintų bifenilų (PCBs) biotinkamumui ir biodegradacijai nustatyti Santrauka Sukonstruoti du ląsteliniai bioindikatoriai polichlorintų bifenilų in situ biodegradacijai nustatyti chromosominiu konstrukto mini-Tn5-KmF -Pm::gfp[mut3]-T0 -T1 įterpimo į P. fluorescens būdu. Bandymai dirbtinėmis sąlygomis parodė, kad Pm aktyviklio išraiška priklauso nuo bioindikatoriaus augimo fazės ir cheminių indikatorių koncentracijos, taip pat nuo chlorintų benzenkarboksirūgščių derinių. Nustatyta tiesinė priklausomybė tarp fluorescentų intensyvumo ir indikatorių log10 koncentracijos. Vienas iš bioindikatorių (F113L::1180gfp) galėjo degraduoti PCBs iki tinkamų chlorobenzenkarboksirūgščių derinių ir indukuoti Gfp išraišką. Antrasis bioindikatorius (F113gfp), kuris negali degraduoti PCBs, parodo fluorescentiškumą įvykus indukcijai pagal chloro-benzenkarboksirūgščių derinius. Naudojant šiuos du bioindikatorius, PCB degradacija gali būti nustatyta tiek dirbtinėmis sąlygomis, tiek dirvožemyje. Reikšminiai žodžiai: bioindikatoriai, Pseudomonas fluorescens F113, PCBs, rizosfera, šaknų kolonizacija. Совершенствование биосенсоров основы gfp для определения биосоответствия и биодеградации полихлорированных бифенилов (PCBs) Резюме Сконструированы два клеточных биоиндикатора для выявления на участке биодеградации полихлорированных бифенилов путем хромосомного введения мини-Tn5-Kmr-Pm::gfp[mut3]-T0-T1 в P. fluorescen. Испытания в искусственных условиях показали, что выражение активатора Pm зависит от фазы роста биоиндикатора и концентрации химических индикаторов, а также от сочетаний хлорированных бензойных кислот. Наблюдалась линейная зависимость между интенсивностью флуоресцентов и концентрации log10 индикаторов. Один из индикаторов (F113L::1180gfp) мог способствовать деградации PCBs в сочетания соответствующих хлор-бензойных кислот и индуцировать выражение Gfp. Другой биоиндикатор (F113gfp), который не может способствовать деградации PCBs, показал флуоресцентность после индикации по сочетаниям хлор-бензойных кислот. С использованием этих индикаций деградация PCB может наблюдаться лишь в искусственных условиях и лишь в почве. Ключевые слова: биоиндикаторы, Pseudomonas fluorescens F113, PCBs, ризосфера, корневая колонизация. First Published Online: 14 Oct 201

Identification of the major proteins of an immune modulating fraction from adult Fasciola hepatica released by Nonidet P40

Fasciola hepatica NP-40 released antigens (FhTeg) exhibit potent Th1 immunosuppressive properties in vitro and in vivo. However, the protein composition of this active fraction, responsible for Th1 immune modulatory activity, has yet to be resolved. Therefore, FhTeg, a Nonidet P-40 extract, was subjected to a proteomic analysis in order to identify individual protein components. This was performed using an in house F. hepatica EST database following 2D electrophoresis combined with de novo sequencing based mass spectrometry. The identified proteins, a mixture of excretory/secretory and membrane-associated proteins, are associated with stress response and chaperoning, energy metabolism and cytoskeletal components. The immune modulatory properties of these identified protein(s) is discussed and HSP70 from F. hepatica is highlighted as a potential host immune modulator for future study