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The mouth may be presented and understood in different ways, be subject to judgement by others and, as we age, may intrude on everyday life due to problems that affect oral health. However, research that considers older people's experiences concerning their mouths and teeth is limited. This paper reports on qualitative research with 43 people in England and Scotland, aged 65–91, exploring the significance of the mouth over the lifecourse. It uses the concept of ‘mouth talk’ to explore narratives of maintaining, losing and replacing teeth. Participants engaged in ‘mouth talk’ to downplay the impact of the mouth, demonstrate socially appropriate ageing, and distance themselves from ‘real’ old age by retaining a moral identity and sense of self. They also found means to challenge dominant discourses of ageing in how they spoke about missing teeth. Referring to Leder's notion of ‘dys-appearance’ and Gilleard and Higgs’ work on the social imaginary of the fourth age, the study illustrates the ways in which ‘mouth talk’ can contribute to sustaining a sense of self in later life, presenting the ageing mouth, with and without teeth, as an absent presence. It also argues for the importance of listening to stories of the mouth in order to expand understanding of people's approaches to oral health in older age.
OBJECTIVES/SPECIFIC AIMS: The goal for this project is to determine the feasibility of using a novel multi-photon fiber-coupled microscope to aid surgeons in localizing STN during surgeries. In order to accomplish this goal, we needed to identify the source of a strong autofluorescent signal in the STN and determine whether we could use image classification methods to automatically distinguish STN from surrounding brain regions. METHODS/STUDY POPULATION: We acquired 3 cadaveric brains from the University of Colorado Anschutz Medical Campus, Department of Pathology. Two of these brains were non-PD controls whereas 1 was diagnosed with PD. We dissected a 10 square centimeter region of midbrain surrounding STN, then prepared this tissue for slicing on a vibratome or cryostat. Samples were immuno-labeled for various cellular markers for identification, or left unlabeled in order to observe the autofluorescence for image classification. RESULTS/ANTICIPATED RESULTS: The border of STN is clearly visible based on the density of a strong autofluorescent signal. The autofluorescent signal is visible using 2-photon (850–1040 nm excitation) and conventional confocal microscopy (488–647 nm excitation). We were also able to visualize blood vessels with second harmonic generation. The autofluorescent signal is quenched by high concentrations of Sudan-black B (0.5%–5%), and is primarily localized in microtubule-associated protein-2 (MAP2)+ cells, indicating that it is likely lipofuscin accumulation in neurons. Smaller lipofuscin particles also accumulate in microglia, identified based on ionized calcium binding adopter 1 (Iba1)+ labeling. We anticipate that colocalization analysis will confirm these qualitative observations. Using 2-photon images of the endogenous autofluorescent signal in these samples, we trained a logistic regression-based image classifier using features derived from gray-level co-occurrence matrices. Preliminary testing indicates that our classifier performed well, with a mean accuracy of 0.89 (standard deviation of 0.11) and a Cohen’s Kappa value of 0.76 (standard deviation of 0.24). We are currently using coherent anti-Stokes Raman scattering and third harmonic imaging to identify different features of myelin that can be used to distinguish between these regions and expect similar results. DISCUSSION/SIGNIFICANCE OF IMPACT: Traditional methods for localizing STN during DBS surgery include the use of stereotactic coordinates and multi-electrode recording (MER) during implantation. MERs are incredibly useful in DBS surgeries, but require penetration of brain structures in order to infer location. Using multi-photon microscopy techniques to aid identification of STN during DBS surgeries offers a number of advantages over traditional methods. For example, blood vessels can be clearly identified with second harmonic generation, something that is not possible with MER. Multi-photon microscopy also allows visualization deep into tissue without actually penetrating it. This ability to look within a depth of field is useful for detection of STN borders based on autofluorescent cell density. When combined with traditional stereotactic information, our preliminary image classification methods are a fast, reliable way to provide surgeons with extra information concerning their location in the midbrain. We anticipate that future advancements and refinements to our image classifier will only increase accuracy and the potential applications and value. In summary, these preliminary data support the feasibility of multi-photon microscopy to aid in the identification of target brain regions during DBS surgeries. The techniques described here complement and enhance current stereotactic and electrophysiological methods for DBS surgeries.
Kohlrausch and others have recently published investigations which show that the electrolytic conductivity of dilute solutions of inorganic salts may be determined with a maximum error of two or three in ten thousand.
Hitherto such accuracy has not been attained with highly conducting concentrated solutions. With such solutions different difficulties are encountered from those met with in dilute solutions. Temperature variations originating outside the cell, the heating effect of the current within the cell, and polarisation are sources of error which are particularly troublesome in the case of highly conducting solutions.
Foods and dietary patterns that enhance satiety may provide benefit to consumers. The aim of the present review was to describe, consider and evaluate research on potential benefits of enhanced satiety. The proposal that enhanced satiety could only benefit consumers by a direct effect on food intake should be rejected. Instead, it is proposed that there is a variety of routes through which enhanced satiety could (indirectly) benefit dietary control or weight-management goals. The review highlights specific potential benefits of satiety, including: providing appetite control strategies for consumers generally and for those who are highly responsive to food cues; offering pleasure and satisfaction associated with low-energy/healthier versions of foods without feeling ‘deprived’; reducing dysphoric mood associated with hunger especially during energy restriction; and improved compliance with healthy eating or weight-management efforts. There is convincing evidence of short-term satiety benefits, but only probable evidence for longer-term benefits to hunger management, possible evidence of benefits to mood and cognition, inadequate evidence that satiety enhancement can promote weight loss, and no evidence on which consumers would benefit most from satiety enhancement. The appetite-reducing effects of specific foods or diets will be much more subtle than those of pharmaceutical compounds in managing hunger; nevertheless, the experience of pharmacology in producing weight loss via effects on appetite suggests that there is potential benefit of satiety enhancement from foods incorporated into the diet to the consumer.
The Dominion Radio Astrophysical Observatory (DRAO) is carrying out a survey as part of an international collaboration to image the northe, at a common resolution, in emission from all major constituents of the interstellar medium; the neutral atomic gas, the molecular gas, the ionised gas, dust and relativistic plasma. For many of these constituents the angular resolution of the images (1 arcmin) will be more than a factor of 10 better than any previous studies. The aim is to produce a publicly-available database of high resolution, high-dynamic range images of the Galaxy for multi-phase studies of the physical states and processes in the interstellar medium. We will sketch the main scientific motivations as well as describe some preliminary results from the Canadian Galactic Plane Survey/Releve Canadien du Plan Galactique (CGPS/RCPG).
A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (H i) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of H i emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b| < 10°) at all declinations south of δ = +40°, spanning longitudes 167° through 360°to 79° at b = 0°, plus the entire area of the Magellanic Stream and Clouds, a total of 13 020 deg2. The brightness temperature sensitivity will be very good, typically σT≃ 1 K at resolution 30 arcsec and 1 km s−1. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.
Selective epitaxial growth (SEG) of silicon-germanium (SiGe) films on patterned-oxide silicon substrates, using a tubular hot-wall low pressure chemical vapor deposition (LPCVD) system, is demonstrated in this study. This conventional system is proposed as a low cost alternative for SiGe epitaxial growth. Three process improvements needed to achieve quality growth are discussed. First, the hydrogen bake process is modified to eliminate Ge-outgassing. Secondly, a Si SEG buffer layer is deposited prior to SiGe SEG. Finally, a small flow of dichlorosilane is introduced during the temperature ramp-down period prior to SiGe SEG. The growth results are discussed in terms of growth selectivity, thickness uniformity, growth rate, defect density, SiGe film composition, and electrical properties.
ZnSe/GaAs heterojunctions were investigated by contactless electroreflectance and photoreflectance techniques. Negative surface charge densities on the order of 1012 cm-2 were observed for films grown on n-type GaAs indicating a large contribution to the conduction band barrier between the materials due to band bending. The conduction band offset was also measured using a new photoreflectance technique involving a tunable pump laser.
Faecal microbial changes associated with ageing include reduced bifidobacteria numbers. These changes coincide with an increased risk of disease development. Prebiotics have been observed to increase bifidobacteria numbers within humans. The present study aimed to determine if prebiotic galacto-oligosaccharides (GOS) could benefit a population of men and women of 50 years and above, through modulation of faecal microbiota, fermentation characteristics and faecal water genotoxicity. A total of thirty-seven volunteers completed this randomised, double-blind, placebo-controlled crossover trial. The treatments – juice containing 4 g GOS and placebo – were consumed twice daily for 3 weeks, preceded by 3-week washout periods. To study the effect of GOS on different large bowel regions, three-stage continuous culture systems were conducted in parallel using faecal inocula from three volunteers. Faecal samples were microbially enumerated by quantitative PCR. In vivo, following GOS intervention, bifidobacteria were significantly more compared to post-placebo (P = 0·02). Accordingly, GOS supplementation had a bifidogenic effect in all in vitro system vessels. Furthermore, in vessel 1 (similar to the proximal colon), GOS fermentation led to more lactobacilli and increased butyrate. No changes in faecal water genotoxicity were observed. To conclude, GOS supplementation significantly increased bifidobacteria numbers in vivo and in vitro. Increased butyrate production and elevated bifidobacteria numbers may constitute beneficial modulation of the gut microbiota in a maturing population.
The General Insurance Board of the Faculty and Institute of Actuaries responded to some of the criticisms raised in the Morris review of the Actuarial Profession and in the press by rating agencies and others, regarding the Actuarial Profession's approach to actuarial reserving in general insurance by setting up a taskforce known as the General Insurance Reserving Issues Taskforce (GRIT). The taskforce worked from 2004 to 2006 and produced a significant report, including some new professional content and recommendations for further areas of development and research. Since then, through the GRIT successor body: the Reserving Oversight Committee (ROC), many working parties have formed and many General Insurance Research Organisation (GIRO) presentations and papers have been forthcoming. One area that has been a recurring theme through the last five years is how the Profession models and communicates the uncertainty in the claims reserving process. In the context of recent events in global financial markets, the forthcoming new regulatory framework of Solvency II, and the developments in other professions globally through IFRS and other drivers, it is timely that actuaries take stock of the many changes in our practices over the last five years and consider the direction actuaries should take for the challenges that lie ahead. This paper is a meta-study of the output of GRIT and ROC on reserving and uncertainty, with the intention of meeting these objectives.
Medium-range order has been observed in ion-implanted amorphous silicon, suggesting a paracrystalline structure for this material. The origin of a paracrystalline structure may be due to an energy spike phenomenon. To evaluate the influence of energy spikes on a particular process, we have attempted to calculate the characteristic energy in a spike. However, the observed depth dependence of amorphous structures in as-implanted silicon is puzzling. To explain this, we simulated the depth distribution of cascade events in a particular energy range. We found a great increase of point defect concentration and cascade events as the depth increases. This result could explain the experimental depth dependence.
Growth of Si/SiGe superlattices on Si substrates by molecular beam epitaxy (MBE) is described. Strain symmetrization in the superlattice is achieved with an incommensurate SiGe buffer layer. The concept of strainsymmetrization is explained and properties of buffer and strained layer superlattices are investigated. A twodimensional electron gas with enhanced room temperature mobility and folded phonon modes within the reduced onedimensional Brillouin zone are observed. An n-channel Si/SiGe MODFET demonstrates the device applications of this material concept.