Mapping Hydrogen in the Galaxy, Galactic Halo, and Local Group with ALFA: The GALFA-HI Survey Starting with TOGS

Radio observations of gas in the Milky Way and Local Group are vital for understanding how galaxies function as systems. The unique sensitivity of Arecibo's 305m dish, coupled with the 7-beam Arecibo L-Band Feed Array (ALFA), provides an unparalleled tool for investigating the full range of interstellar phenomena traced by the HI 21cm line. The GALFA (Galactic ALFA) HI Survey is mapping the entire Arecibo sky over a velocity range of -700 to +700 km/s with 0.2 km/s velocity channels and an angular resolution of 3.4 arcminutes. We present highlights from the TOGS (Turn on GALFA Survey) portion of GALFA-HI, which is covering thousands of square degrees in commensal drift scan observations with the ALFALFA and AGES extragalactic ALFA surveys. This work is supported in part by the National Astronomy and Ionosphere Center, operated by Cornell University under cooperative agreement with the National Science Foundation.Comment: 3 pages, including 2 figure pages; figure image quality significantly reduced; for full resolution version, please see http://www.naic.edu/~gibson/cv/ao08_writeup.pdf ; to be published in AIP conference proceedings for ``The Evolution of Galaxies through the Neutral Hydrogen Window'', eds. R. Minchin & E. Momjia

A novel Bayesian approach to quantify clinical variables and to determine their spectroscopic counterparts in 1H NMR metabonomic data

<p>Abstract</p> <p>Background</p> <p>A key challenge in metabonomics is to uncover quantitative associations between multidimensional spectroscopic data and biochemical measures used for disease risk assessment and diagnostics. Here we focus on clinically relevant estimation of lipoprotein lipids by ¹H NMR spectroscopy of serum.</p> <p>Results</p> <p>A Bayesian methodology, with a biochemical motivation, is presented for a real ¹H NMR metabonomics data set of 75 serum samples. Lipoprotein lipid concentrations were independently obtained for these samples via ultracentrifugation and specific biochemical assays. The Bayesian models were constructed by Markov chain Monte Carlo (MCMC) and they showed remarkably good quantitative performance, the predictive R-values being 0.985 for the very low density lipoprotein triglycerides (VLDL-TG), 0.787 for the intermediate, 0.943 for the low, and 0.933 for the high density lipoprotein cholesterol (IDL-C, LDL-C and HDL-C, respectively). The modelling produced a kernel-based reformulation of the data, the parameters of which coincided with the well-known biochemical characteristics of the ¹H NMR spectra; particularly for VLDL-TG and HDL-C the Bayesian methodology was able to clearly identify the most characteristic resonances within the heavily overlapping information in the spectra. For IDL-C and LDL-C the resulting model kernels were more complex than those for VLDL-TG and HDL-C, probably reflecting the severe overlap of the IDL and LDL resonances in the ¹H NMR spectra.</p> <p>Conclusion</p> <p>The systematic use of Bayesian MCMC analysis is computationally demanding. Nevertheless, the combination of high-quality quantification and the biochemical rationale of the resulting models is expected to be useful in the field of metabonomics.</p

Fine-resolution mapping of microforms of a boreal bog using aerial images and waveform-recording LiDAR

Boreal bogs are important stores and sinks of atmospheric carbon whose surfaces are characterised by vegetation microforms. Efficient methods for monitoring their vegetation are needed because changes in vegetation composition lead to alteration in their function such as carbon gas exchange with the atmosphere. We investigated how airborne image and waveform-recording LiDAR data can be used for 3D mapping of microforms in an open bog which is a mosaic of pools, hummocks with a few stunted pines, hollows, intermediate surfaces and mud-bottom hollows. The proposed method operates on the bog surface, which is reconstructed using LiDAR. The vegetation was classified at 20 cm resolution. We hypothesised that LiDAR data describe surface topography, moisture and the presence and depth of field-layer vegetation and surface roughness; while multiple images capture the colours and texture of the vegetation, which are influenced by directional reflectance effects. We conclude that geometric LiDAR features are efficient predictors of microforms. LiDAR intensity and echo width were specific to moisture and surface roughness, respectively. Directional reflectance constituted 4-34 % of the variance in images and its form was linked to the presence of the field layer. Microform-specific directional reflectance patterns were deemed to be of marginal value in enhancing the classification, and RGB image features were inferior to LiDAR variables. Sensor fusion is an attractive option for fine-scale mapping of these habitats. We discuss the task and propose options for improving the methodology.Peer reviewe

Dental students’ and patients’ perceived importance and knowledge of dental anxiety

Abstract Aim: To examine the perceived importance and knowledge of the dental students’ in their treatment of dental anxiety according to their year of study and to find out patients’ perceived importance of the dental students’ knowledge of dental anxiety according to their level on dental fear. Methods: Dental students (N = 219) at the University of Turku and non‐probability convenience sample of 100 of patients attending the Dental Teaching Clinic were given questionnaires with multiple choice and open‐ended questions. Students were categorised into three groups according to the year of study (1–3, 4, 5). Patients were categorised into three groups using the established cut points for Modified Dental Anxiety Scale (no fear = 5–9, low fear = 10–18, high fear = 19–25). The differences between groups were evaluated using cross‐tabulations, chi squared and Fisher’s exact tests. The open‐ended questions were subjected to content analysis. Results: Students’ perceived importance of dental anxiety did not differ between three groups. Students with greater undergraduate education and clinical experience were more likely to have excellent or quite good knowledge (P &lt; 0.001). Patients’ perceived importance of dental students’ knowledge of dental anxiety was greater in patients with high level of fear. The overlapping category that emerged from the open‐ended question analysis was communication skills. This appeared to be important for patients with dental anxiety and for dental students in their management of dental anxiety. Conclusion: Clinical communication skills should be part of dental anxiety management teaching. Dental students should be able to gain sufficient knowledge and skills in treating dental anxiety before graduating

Evidence for local aldosterone synthesis in the large intestine of the mouse

Aldosterone, the main physiological mineralocorticoid, regulates sodium and potassium balance in the distal convoluted tubule of the kidney. Aldosterone is synthesized from cholesterol in the adrenal cortex in a sequence of enzymatic steps. Recently however, several tissues or cells e.g. brain, heart, blood vessels, kidneys and adipocytes have been shown to possess capability to produce aldosterone locally, and there is some evidence that this occurs also in the intestine. Colon expresses mineralocorticoid receptors and is capable of synthesizing corticosterone, the second last intermediate on the route to aldosterone from cholesterol. Based on such reports and on our preliminary finding, we hypothesized that aldosterone could be synthesized locally in the intestine and therefore we measured the concentration of aldosterone as well as the protein and gene expression of aldosterone synthase (CYP11B2), an enzyme responsible on aldosterone synthesis, from the distal section of the gastrointestinal tract of 10-week-old Balb/c male mice. It is known that sodium deficiency regulates aldosterone synthesis in adrenal glands, therefore we fed the mice with low (0.01%), normal (0.2%) and high-sodium (1.6%) diets for 14 days. Here we report that, aldosterone was detected in colon and cecum samples. Measurable amounts of CYP11B2 protein were detected by Western blot and Elisa analysis from both intestinal tissues. We detected CYP1182 gene expression from the large intestine along with immunohistochemical findings of CYP11B2 in colonic wall. Sodium depletion increased the aldosterone concentration in plasma compared to control and high-sodium groups as well as in the intestine compared to mice fed with the high-sodium diet. To summarize, this study further supports the presence of aldosterone and the enzyme needed to produce this mineralocorticoid in the murine large intestine.Peer reviewe

Intestinal permeability to iohexol as an in vivo marker of chemotherapy-induced gastrointestinal toxicity in Sprague-Dawley rats

Gastrointestinal toxicity is the most common adverse effect of chemotherapy. Chemotherapeutic drugs damage the intestinal mucosa and increase intestinal permeability. Intestinal permeability is one of the key markers of gastrointestinal function and measuring intestinal permeability could serve as a useful tool for assessing the severity of chemotherapy-induced gastrointestinal toxicity.Peer reviewe

Cohort profile: Finnish Health and Early Life Microbiota (HELMi) longitudinal birth cohort

Peer reviewe