466 research outputs found
HD 24355 observed by the Kepler K2 mission: a rapidly oscillating Ap star pulsating in a distorted quadrupole mode
We present an analysis of the first Kepler K2 mission observations of a rapidly oscillating Ap (roAp) star, HD 24355 (V = 9.65). The star was discovered in SuperWASP broad-band photometry with a frequency of 224.31 d−1 (2596.18 μHz; P = 6.4 min) and an amplitude of
1.51 mmag, with later spectroscopic analysis of low-resolution spectra showing HD 24355 to
be an A5 Vp SrEu star. The high-precision K2 data allow us to identify 13 rotationally split sidelobes to the main pulsation frequency of HD 24355. This number of sidelobes combined with an unusual rotational phase variation show this star to be the most distorted quadrupole roAp pulsator yet observed. In modelling this star, we are able to reproduce well the amplitude modulation of the pulsation, and find a close match to the unusual phase variations. We show this star to have a pulsation frequency higher than the critical cut-off frequency. This is currently the only roAp star observed with the Kepler spacecraft in short cadence mode that has a photometric amplitude detectable from the ground, thus allowing comparison between the mmag amplitude ground-based targets and the μmag spaced-based discoveries. No further pulsation modes are identified in the K2 data, showing this star to be a single-mode pulsator
Skillful spring forecasts of September Arctic sea ice extent using passive microwave sea ice observations
In this study, we demonstrate skillful spring forecasts of detrended September Arctic sea ice extent using passive microwave observations of sea ice concentration (SIC) and melt onset (MO). We compare these to forecasts produced using data from a sophisticated melt pond model, and find similar to higher skill values, where the forecast skill is calculated relative to linear trend persistence. The MO forecasts shows the highest skill in March–May, while the SIC forecasts produce the highest skill in June–August, especially when the forecasts are evaluated over recent years (since 2008). The high MO forecast skill in early spring appears to be driven primarily by the presence and timing of open water anomalies, while the high SIC forecast skill appears to be driven by both open water and surface melt processes. Spatial maps of detrended anomalies highlight the drivers of the different forecasts, and enable us to understand regions of predictive importance. Correctly capturing sea ice state anomalies, along with changes in open water coverage appear to be key processes in skillfully forecasting summer Arctic sea ice
Suppressed phase variations in a high amplitude rapidly oscillating Ap star pulsating in a distorted quadrupole mode
We present the results of a multisite photometric observing campaign on the rapidly oscillating Ap (roAp) star 2MASS 16400299-0737293 (J1640; ). We analyse photometric data to show the star pulsates at a frequency of d (Hz; min) with a peak-to-peak amplitude of 20.68 mmag, making it one of the highest amplitude roAp stars. No further pulsation modes are detected. The stellar rotation period is measured at d, and we show that rotational modulation due to spots is in anti-phase between broadband and observations. Analysis and modelling of the pulsation reveals this star to be pulsating in a distorted quadrupole mode, but with a strong spherically symmetric component. The pulsational phase variation in this star is suppressed, leading to the conclusion that the contribution of components dictate the shape of phase variations in roAp stars that pulsate in quadrupole modes. This is only the fourth time such a strong pulsation phase suppression has been observed, leading us to question the mechanisms at work in these stars. We classify J1640 as an A7 Vp SrEu(Cr) star through analysis of classification resolution spectra
Feedback on video recorded consultations in medical teaching: why students loathe and love it – a focus-group based qualitative study
BACKGROUND: Feedback on videotaped consultations is a useful way to enhance consultation skills among medical students. The method is becoming increasingly common, but is still not widely implemented in medical education. One obstacle might be that many students seem to consider this educational approach a stressful experience and are reluctant to participate. In order to improve the process and make it more acceptable to the participants, we wanted to identify possible problems experienced by students when making and receiving feedback on their video taped consultations. METHODS: Nineteen of 75 students at the University of Bergen, Norway, participating in a consultation course in their final term of medical school underwent focus group interviews immediately following a video-based feedback session. The material was audio-taped, transcribed, and analysed by phenomenological qualitative analysis. RESULTS: The study uncovered that some students experienced emotional distress before the start of the course. They were apprehensive and lacking in confidence, expressing fear about exposing lack of skills and competence in front of each other. The video evaluation session and feedback process were evaluated positively however, and they found that their worries had been exaggerated. The video evaluation process also seemed to help strengthen the students' self esteem and self-confidence, and they welcomed this. CONCLUSION: Our study provides insight regarding the vulnerability of students receiving feedback from videotaped consultations and their need for reassurance and support in the process, and demonstrates the importance of carefully considering the design and execution of such educational programs
Phase 1 development of an index to measure the quality of neuraxial labour analgesia: exploring the perspectives of childbearing women
Observed communication skills: how do they relate to the consultation content? A nation-wide study of graduate medical students seeing a standardized patient for a first-time consultation in a general practice setting
<p>Abstract</p> <p>Background</p> <p>In this study, we wanted to investigate the relationship between background variables, communication skills, and the bio-psychosocial content of a medical consultation in a general practice setting with a standardized patient.</p> <p>Methods</p> <p>Final-year medical school students (N = 111) carried out a consultation with an actor playing the role of a patient with a specific somatic complaint, psychosocial stressors, and concerns about cancer. Based on videotapes, communication skills and consultation content were scored separately.</p> <p>Results</p> <p>The mean level of overall communication skills had a significant impact upon the counts of psychosocial issues, the patient's concerns about cancer, and the information and planning parts of the consultation content being addressed. Gender and age had no influence upon the relationship between communication skills and consultation content.</p> <p>Conclusion</p> <p>Communication skills seem to be important for final-year students' competence in addressing sensitive psychosocial issues and patients' concerns as well as informing and planning with patients being representative for a fairly complex case in general practice. This result should be considered in the design and incorporation of communication skills training as part of the curriculum of medical schools.</p
Phylogenetic comparative assembly
Husemann P, Stoye J. Phylogenetic Comparative Assembly. Algorithms for Molecular Biology. 2010;5(1): 3.BACKGROUND:Recent high throughput sequencing technologies are capable of generating a huge amount of data for bacterial genome sequencing projects. Although current sequence assemblers successfully merge the overlapping reads, often several contigs remain which cannot be assembled any further. It is still costly and time consuming to close all the gaps in order to acquire the whole genomic sequence. RESULTS:Here we propose an algorithm that takes several related genomes and their phylogenetic relationships into account to create a graph that contains the likelihood for each pair of contigs to be adjacent. Subsequently, this graph can be used to compute a layout graph that shows the most promising contig adjacencies in order to aid biologists in finishing the complete genomic sequence. The layout graph shows unique contig orderings where possible, and the best alternatives where necessary. CONCLUSIONS:Our new algorithm for contig ordering uses sequence similarity as well as phylogenetic information to estimate adjacencies of contigs. An evaluation of our implementation shows that it performs better than recent approaches while being much faster at the same tim
Cancer Stem Cell-Like Cells Derived from Malignant Peripheral Nerve Sheath Tumors
This study aims to examine whether or not cancer stem cells exist in malignant peripheral nerve sheath tumors (MPNST). Cells of established lines, primary cultures and freshly dissected tumors were cultured in serum free conditions supplemented with epidermal and fibroblast growth factors. From one established human MPNST cell line, S462, cells meeting the criteria for cancer stem cells were isolated. Clonal spheres were obtained, which could be passaged multiple times. Enrichment of stem cell-like cells in these spheres was also supported by increased expression of stem cell markers such as CD133, Oct4, Nestin and NGFR, and decreased expression of mature cell markers such as CD90 and NCAM. Furthermore, cells of these clonal S462 spheres differentiated into Schwann cells, smooth muscle/fibroblast and neurons-like cells under specific differentiation-inducing cultural conditions. Finally, subcutaneous injection of the spheres into immunodeficient nude mice led to tumor formation at a higher rate compared to the parental adherent cells (66% versus 10% at 2.5×105). These results provide evidence for the existence of cancer stem cell-like cells in malignant peripheral nerve sheath tumors
GenomeBlast: a web tool for small genome comparison
BACKGROUND: Comparative genomics has become an essential approach for identifying homologous gene candidates and their functions, and for studying genome evolution. There are many tools available for genome comparisons. Unfortunately, most of them are not applicable for the identification of unique genes and the inference of phylogenetic relationships in a given set of genomes. RESULTS: GenomeBlast is a Web tool developed for comparative analysis of multiple small genomes. A new parameter called "coverage" was introduced and used along with sequence identity to evaluate global similarity between genes. With GenomeBlast, the following results can be obtained: (1) unique genes in each genome; (2) homologous gene candidates among compared genomes; (3) 2D plots of homologous gene candidates along the all pairwise genome comparisons; and (4) a table of gene presence/absence information and a genome phylogeny. We demonstrated the functions in GenomeBlast with an example of multiple herpesviral genome analysis and illustrated how GenomeBlast is useful for small genome comparison. CONCLUSION: We developed a Web tool for comparative analysis of small genomes, which allows the user not only to identify unique genes and homologous gene candidates among multiple genomes, but also to view their graphical distributions on genomes, and to reconstruct genome phylogeny. GenomeBlast runs on a Linux server with 4 CPUs and 4 GB memory. The online version of GenomeBlast is available to public by using a Web browser with the URL
Doctor–patient communication in a Southeast Asian setting: the conflict between ideal and reality
Doctor–patient communication has been extensively studied in non-Western contexts and in relation to patients’ cultural and education backgrounds. This study explores the perceived ideal communication style for doctor–patient consultations and the reality of actual practice in a Southeast Asian context. We conducted the study in a teaching hospital in Indonesia, using a qualitative and a quantitative design. In-depth interviews were conducted with ten internal medicine specialists, ten internal medicine residents, 16 patients in two groups based on education level and ten most senior medical students. The contributions of doctors and patients to the communication during consultations were observed and rated quantitatively by thirty internal medicine residents, 393 patients with different educational backgrounds and ten senior medical students. The ‘informed and shared decision making’ is the central observation in this quantitative study. The results of the interviews showed that Southeast Asian stakeholders are in favor of a partnership style of communication and revealed barriers to achieving this: doctors and patients are not prepared for a participatory style and high patient load due to an inefficient health care system does not allow sufficient time for this type of communication. The results of the quantitative study showed a sharp contrast between observed and ideal communication styles. A paternalistic style seems to prevail, irrespective of patients’ educational background. We found a sharp conflict between ideal and reality concerning doctor–patient communication in a Southeast Asian context. Further studies should examine ways to change the prevailing communication style in the desired direction
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