Mechanical and Topographical Changes on Dentine Following Citric Acid Exposure

Objectives: 1. To determine the effects of short-term exposure of dentine to different concentrations and pH of citric acid; 2. To determine the stiffness and topographical changes associated with dentine erosion. Methods: Bovine incisors were prepared into 20 dentine discs (5mm3 ) and polished with 0.05\ub5m Al2 O 3 paste. Erosion was measured in terms of topographical and stiffness changes using atomic force microscope (AFM, Nanowizard 3, JPK Instruments). Specimens were exposed via the AFM liquid flow-cell to 1wt% or 6wt% citric acid, either unbuffered (pH 2.17 or 1.88, respectively) or buffered (pH 3.8) for repeated 20s cycles of citric acid up-to 120s. Baseline measured in PBS only. A representative sample was selected from each group for post-erosion scanning electron microscope (SEM) assessment. Results: Table 1 outlines stiffness results and AFM topography images demonstrate all groups post-erosion. The 1% buffered group had the least measurable changes across all time intervals and the 6% unbuffered citric acid had the greatest overall impact on the surface. The 6% buffered acid was more erosive compared with the 1% unbuffered acid, in terms of both stiffness and topography changes, between 20s and 80s exposures. However, the 1% unbuffered group had similar erosive surface changes, as for the 6% buffered samples, with increasing exposure times at 100s onwards. SEM and AFM topography showed a similar loss of peri-tubular dentine with enlargement of the tubules. AFM also demonstrated increased surface height variations with increasing exposure times and similar erosive trends to mechanical stiffness changes. Conclusions: The data shows that citric acid concentration is more critical to early erosive changes on dentine compared with a lower pH, demonstrated by stiffness elasticity reduction and structural changes. The 1% buffered group was the least erosive acid, compared with the 6% unbuffered solution which had the greatest surface changes. These AFM findings were supported by SEM dat

Mental health research projects: a practical integration of mental health into a medical curriculum

Abstract of a paper presented at the 65th Annual National Conference of Indian Psychiatric Society, Bangalor, 10-13 Jan, 2013. Aims aJld Objectives: The University of Wollongong (UoW) graduate-entry medical course embeds research and critical analysis within the curriculum, concluding with students undertaking a regional/ nlrsl conmlUnity-based ro earch project. Students are encouraged to design a research project of interest to them and the local community. T.his Indy analyzed whether conducting research projects enhanced learning/understanding about rural/regional mental health issues amongst UoW medical students

GWIPS-viz: 2018 update

The GWIPS-viz browser (http://gwips.ucc.ie/) is an on-line genome browser which is tailored for exploring ribosome profiling (Ribo-seq) data. Since its publication in 2014, GWIPS-viz provides Ribo-seq data for an additional 14 genomes bringing the current total to 23. The integration of new Ribo-seq data has been automated thereby increasing the number of available tracks to 1792, a 10-fold increase in the last three years. The increase is particularly substantial for data derived from human sources. Following user requests, we added the functionality to download these tracks in bigWig format. We also incorporated new types of data (e.g. TCP-seq) as well as auxiliary tracks from other sources that help with the interpretation of Ribo-seq data. Improvements in the visualization of the data have been carried out particularly for bacterial genomes where the Ribo-seq data are now shown in a strand specific manner. For higher eukaryotic datasets, we provide characteristics of individual datasets using the RUST program which includes the triplet periodicity, sequencing biases and relative inferred A-site dwell times. This information can be used for assessing the quality of Ribo-seq datasets. To improve the power of the signal, we aggregate Ribo-seq data from several studies into Global aggregate tracks for each genome

Kramers rate theory of ionization and dissociation of bound states

Calculating the microscopic dissociation rate of a bound state, such as a classical diatomic molecule, has been difficult so far. The problem was that standard theories require an energy barrier over which the bound particle (or state) escapes into the preferred low-energy state. This is not the case when the long-range repulsion responsible for the barrier is either absent or screened (as in Cooper pairs, ionized plasma, or biomolecular complexes). We solve this classical problem by accounting for entropic memory at the microscopic level. The theory predicts dissociation rates for arbitrary potentials and is successfully tested on the example of plasma, where it yields an estimate of ionization in the core of Sun in excellent agreement with experiments. In biology, the new theory accounts for crowding in receptor-ligand kinetics and protein aggregation

The challenge of patients’ unmet palliative care needs in the final stages of chronic illness.

Background: There is consensus in the literature that the end of life care for patients with chronic illness is suboptimal, but research on the specific needs of this population is limited. Aim: This study aimed to use a mixed methodology and case study approach to explore the palliative care needs of patients with a non-cancer diagnosis from the perspectives of the patient, their significant other and the clinical team responsible for their care. Patients (n 18) had a diagnosis of either end-stage heart failure, renal failure or respiratory disease. Methods: The Short Form 36 and Hospital and Anxiety and Depression Questionnaire were completed by all patients. Unstructured interviews were (n 35) were conducted separately with each patient and then their significant other. These were followed by a focus group discussion (n 18) with the multiprofessional clinical team. Quantitative data were analysed using simple descriptive statistics and simple descriptive statistics. All qualitative data were taped, transcribed and analysed using Colaizzi’s approach to qualitative analysis. Findings: Deteriorating health status was the central theme derived from this analysis. It led to decreased independence, social isolation and family burden. These problems were mitigated by the limited resources at the individual’s disposal and the availability of support from hospital and community services. Generally resources and support were perceived as lacking. All participants in this study expressed concerns regarding the patients’ future and some patients described feelings of depression or acceptance of the inevitability of imminent death. Conclusion: Patients dying from chronic illness in this study had many concerns and unmet clinical needs. Care teams were frustrated by the lack of resources available to them and admitted they were ill-equipped to provide for the individual’s holistic needs. Some clinicians described difficulty in talking openly with the patient and family regarding the palliative nature of their treatment. An earlier and more effective implementation of the palliative care approach is necessary if the needs of patients in the final stages of chronic illness are to be adequately addressed. P