54 research outputs found
Videos in STEM courses: A 21st century tool in higher education
The call for actively engaging students in the STEM classroom has increased to a clamour in recent years – in the field of biology, this is reflected through the call for student-centered learning in the 2011 AAAS Vision and Change document (http://visionandchange.org). The flipped classroom is arguably the most student-centered and interactive of the various active learning approaches. Central to this type of course are the instructional videos that students watch before class. While the concept of a flipped class may be of interest to many, the need to create these videos is often the perceived obstacle that prevents adoption of a flipped approach. Outside of the flipped classroom, there are a variety of other uses for instructor-created videos. In this presentation, we will discuss how we have incorporated instructional videos, lecture capture and screencasts in our flipped, blended and non-flipped courses. Participants will learn how simple these videos are to make and disseminate and will hear about the various types and uses of instructional videos. They will have the opportunity to debate the pros and cons of possibly the most controversial of instructional videos: lecture capture. Many dental and medical schools have been recording their lectures for years, yet this practice is not common in STEM education: why? The session will end with participants brainstorming possible uses for their own courses. In a follow-up workshop, we will provide hands-on experience to help participants make their own short instructional videos
Observations of Coronal Mass Ejections with the Coronal Multichannel Polarimeter
The Coronal Multichannel Polarimeter (CoMP) measures not only the
polarization of coronal emission, but also the full radiance profiles of
coronal emission lines. For the first time, CoMP observations provide
high-cadence image sequences of the coronal line intensity, Doppler shift and
line width simultaneously in a large field of view. By studying the Doppler
shift and line width we may explore more of the physical processes of CME
initiation and propagation. Here we identify a list of CMEs observed by CoMP
and present the first results of these observations. Our preliminary analysis
shows that CMEs are usually associated with greatly increased Doppler shift and
enhanced line width. These new observations provide not only valuable
information to constrain CME models and probe various processes during the
initial propagation of CMEs in the low corona, but also offer a possible
cost-effective and low-risk means of space weather monitoring.Comment: 6 figures. Will appear in the special issue of Coronal Magnetism,
Sol. Phy
Extreme Ultra-Violet Spectroscopy of the Lower Solar Atmosphere During Solar Flares
The extreme ultraviolet portion of the solar spectrum contains a wealth of
diagnostic tools for probing the lower solar atmosphere in response to an
injection of energy, particularly during the impulsive phase of solar flares.
These include temperature and density sensitive line ratios, Doppler shifted
emission lines and nonthermal broadening, abundance measurements, differential
emission measure profiles, and continuum temperatures and energetics, among
others. In this paper I shall review some of the advances made in recent years
using these techniques, focusing primarily on studies that have utilized data
from Hinode/EIS and SDO/EVE, while also providing some historical background
and a summary of future spectroscopic instrumentation.Comment: 34 pages, 8 figures. Submitted to Solar Physics as part of the
Topical Issue on Solar and Stellar Flare
MeerKAT-16 HI observation of the dIrr galaxy WLM
We present observations and models of the kinematics and the distribution of the
neutral hydrogen (Hi) in the isolated dwarf irregular galaxy, Wolf-Lundmark-Melotte
(WLM). We observed WLM with the Green Bank Telescope (GBT) and as part of
the MeerKAT Early Science Programme, where 16 dishes were available. The Hi disc
of WLM extends out to a major axis diameter of 300 (8.5 kpc), and a minor axis
diameter of 200 (5.6 kpc) as measured by the GBT. We use the MeerKAT data to
model WLM using the TiRiFiC software suite, allowing us to t di erent tilted-ring
models and select the one that best matches the observation. Our nal best- tting
model is a
at disc with a vertical thickness, a constant inclination and dispersion,
and a radially-varying surface brightness with harmonic distortions. To simulate bar-
like motions, we include second-order harmonic distortions in velocity in the tangential
and the vertical directions. We present a model with only circular motions included
and a model with non-circular motions. The latter describes the data better. Overall,
the models reproduce the global distribution and the kinematics of the gas, except for
some faint emission at the 2 level. We model the mass distribution of WLM with a
pseudo-isothermal (ISO) and a Navarro-Frenk-White (NFW) dark matter halo models.
The NFW and the ISO models t the derived rotation curves within the formal errors,
but with the ISO model giving better reduced chi-square values. The mass distribution
in WLM is dominated by dark matter at all radii.The MeerKAT telescope is operated by the South African
Radio Astronomy Observatory, which is a facility of the Na-
tional Research Foundation, an agency of the Department
of Science and Innovation.
This work is based upon research supported by the South
African Research Chairs Initiative of the Department of Sci-
ence and Technology and National Research Foundation.
The nancial assistance of the South African Radio Astron-
omy Observatory (SARAO) towards this research is hereby
acknowledged (www.sarao.ac.za).
PK is partially supported by the BMBF project 05A17PC2
for D-MeerKAT.
AS acknowledges the Russian Science Foundation grant
19-12-00281 and the Program of development of M.V.http://mnras.oxfordjournals.orgam2021Physic
Novel genetic loci associated with hippocampal volume
The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness
Skewed X-inactivation is common in the general female population
X-inactivation is a well-established dosage compensation mechanism ensuring that X-chromosomal genes are expressed at comparable levels in males and females. Skewed X-inactivation is often explained by negative selection of one of the alleles. We demonstrate that imbalanced expression of the paternal and maternal X-chromosomes is common in the general population and that the random nature of the X-inactivation mechanism can be sufficient to explain the imbalance. To this end, we analyzed blood-derived RNA and whole-genome sequencing data from 79 female children and their parents from the Genome of the Netherlands project. We calculated the median ratio of the paternal over total counts at all X-chromosomal heterozygous single-nucleotide variants with coverage ≥10. We identified two individuals where the same X-chromosome was inactivated in all cells. Imbalanced expression of the two X-chromosomes (ratios ≤0.35 or ≥0.65) was observed in nearly 50% of the population. The empirically observed skewing is explained by a theoretical model where X-inactivation takes place in an embryonic stage in which eight cells give rise to the hematopoietic compartment. Genes escaping X-inactivation are expressed from both alleles and therefore demonstrate less skewing than inactivated genes. Using this characteristic, we identified three novel escapee genes (SSR4, REPS2, and SEPT6), but did not find support for many previously reported escapee genes in blood. Our collective data suggest that skewed X-inactivation is common in the general population. This may contribute to manifestation of symptoms in carriers of recessive X-linked disorders. We recommend that X-inactivation results should not be used lightly in the interpretation of X-linked variants
The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set
Background
Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables.
Methods
Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set.
Results
Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001).
Conclusions
The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy
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