698 research outputs found
Vaccine Myths: Setting the Record Straight
Despite their standing as one of the most remarkable public health achievements, vaccines have been surrounded by dangerous myths since the development of the smallpox vaccine in the 18th century. In recent decades, with the publication of a fraudulent article linking vaccines to autism, the involvement of celebrities in the debate, and the rise of the internet and social media as sources for information for patients, these myths have become more widespread. This paper reviews four common vaccine myths: vaccines cause autism, vaccines are not safe, too many vaccines are given too soon, and the influenza vaccine is not necessary. For each of these myths, we review the origin and spread of misinformation. The authors then present the scientific evidence against each myth. Extensive research has found no link between vaccines, and particularly the MMR vaccine or the preservative thimerosal, and autism. The U.S. and world health agencies have effective mechanisms in place to review and monitor vaccine safety. These systems have worked to detect and evaluate even rare vaccine adverse events. The recommended vaccine schedule is safe for infants’ immune systems. The flu vaccine is an essential tool in the fight against the seasonal influenza deaths.
A consequence of these myths is that parents are choosing to delay or refuse recommended vaccines for themselves and their children. This has resulted in outbreaks of measles, pertussis, H. influenza type b, varicella, and pneumococcal disease in the United States. Unvaccinated and undervaccinated children risk contracting the disease themselves, and pose a risk to their community as herd immunity decreases. It is important to explore and refute the myths leading to decreased vaccination rates, so health care providers and parents can make educated decisions to protect children and ensure public health
The Effect Of Problem Based Learning On Undergraduate Oral Communication Competency
Purpose: The aim of this study was to ascertain the effect of Problem Based Learning (PBL) on student oral communication competency gains. Methods: Eighty students from two consecutive undergraduate Kinesiology courses (Spring semesters, 2014-15) formed into 29 small groups and were studied. Oral communication competency was assessed using a customized rubric and digital recordings of student presentations. Changes to oral communication competency across time were tested using a dependent t-test; a < .05. Results: Significant inter-rater agreement was found at both time points for oral communication rating, and student groups demonstrated significant oral communication gains across time. Conclusions: Collaborative learning was shown to improve students’ oral communication competency. Future study is required to determine the influence of student motivation and goal orientation on oral communication competency, in relation to the various phases of knowledge creation occurring within student groups.
Running an open MOOC on learning in laboratories
CONTEXT Teaching in laboratories plays an integral role in education. This includes both proximal as well as remote laboratories. In many instances, learning activities are designed around equipment and traditional laboratory activities. Pedagogical aspects and instructional design are often not considered or are an afterthought.
PURPOSE The aim of this project was to help to address this gap by designing, implementing and facilitating an open online course on the pedagogy of using laboratory experiences in the curriculum.
APPROACH The MOOC for Enhancing Laboratory Learning Outcomes (MELLO) has been designed to assist educators at all levels, from schools to universities, to improve the quality of laboratory experiences in STEM (Science, Technology, Engineering, and Mathematics) education. Experienced educators seeking to review and revise current practices or beginning educators were all welcome to participate. Based on learning theory and research literature, online course has been developed that covers constructive alignment of practical activities with the wider curriculum, learning objectives, pedagogical approaches to laboratory learning, laboratory modalities and session planning.
RESULTS 120 participants from Australia and around the world took part in the course. While the participants did not work on their own laboratory activity throughout the courses (as envisaged when designing the course), participants who actively took part in the course were positive about the value of the course.
CONCLUSIONS The MOOC has been capable of supporting a large number of participants including university educators around the world who use laboratory experiences and will continue to do so through future iterations of the course. Moving forward, there is scope to adapt the pedagogical approach of the course to cater for the way the participants
have engaged with the material
Closure statistics in interferometric data
Interferometric visibilities, reflecting the complex correlations between
signals recorded at antennas in an interferometric array, carry information
about the angular structure of a distant source. While unknown antenna gains in
both amplitude and phase can prevent direct interpretation of these
measurements, certain combinations of visibilities called closure phases and
closure amplitudes are independent of antenna gains and provide a convenient
set of robust observables. However, these closure quantities have subtle noise
properties and are generally both linearly and statistically dependent. These
complications have obstructed the proper use of closure quantities in
interferometric analysis, and they have obscured the relationship between
analysis with closure quantities and other analysis techniques such as self
calibration. We review the statistics of closure quantities, noting common
pitfalls that arise when approaching low signal-to-noise due to the nonlinear
propagation of statistical errors. We then develop a strategy for isolating and
fitting to the independent degrees of freedom captured by the closure
quantities through explicit construction of linearly independent sets of
quantities along with their noise covariance in the Gaussian limit, valid for
moderate signal-to-noise, and we demonstrate that model fits have biased
posteriors when this covariance is ignored. Finally, we introduce a unified
procedure for fitting to both closure information and partially calibrated
visibilities, and we demonstrate both analytically and numerically the direct
equivalence of inference based on closure quantities to that based on self
calibration of complex visibilities with unconstrained antenna gains.Comment: 31 pages, 17 figure
Processing Results of western Australian Wool
Despite a perception by some that Western Australian wool \u27processes poorly\u27, this study found that the consignments processed:
1. into longer tops suited for worsted weaving
2. into longer than predicted tops
3. with the same consistency as other Australian consignment
Understanding pathogen transmission dynamics in waterbird communities: At what scale should interactions be studied?
Pathogen transmission in animal populations is contingent on interactions between and within species. Often standard ornithological data (e.g. total counts at a wetland) are the only data available for assessing the risks of avian pathogen transmission. In this paper we ask whether these data can be used to infer fine-scale transmission patterns. We tested for non-randomness in waterbird assemblages and explored waterbird interactions using social network analysis. Certain network parameter values were then compared to a data set on avian influenza prevalence in southern Africa. Our results showed that species associations were strongly non-random, implying that most standard ornithological data sets would not provide adequate information on which to base models of pathogen spread. In both aquatic and terrestrial networks, all species regularly associated closely with other network members. The spread of pathogens through the community could thus be rapid. Network analysis together with detailed, fine-scale observations offers a promising avenue for further research and management-oriented applications
Factors Related to Average Concentric Velocity of Four Barbell Exercises at Various Loads
The resistance exercise load is the primarily determinant of the average concentric velocity (ACV) during a repetition. It is unknown whether individual factors such as training experience or anthropometrics also influence the ACV. Previous research has shown the ACV during the 1 repetition maximum (1RM) varies between exercises, but it is not clear whether ACV is different between exercises at various percentages of the 1RM. This information could provide practical guidelines for trainees using ACV to select training loads. Therefore, the purpose of this study was to determine whether training age, current training frequency, limb length, height, and relative strength are related to ACV at loads between 35 and 100% of the 1RM for the squat, bench press, deadlift, and overhead press. A secondary purpose was to compare the ACV values between the 4 lifts at each relative load. Fifty-one (18 women and 33 men) completed 2 testing sessions in which the squat, bench press, deadlift, and overhead press ACV were measured during a modified 1RM protocol. Average concentric velocity values were significantly different among the 4 lifts (p \u3c 0.05) at all relative loads between 35 and 100% 1RM except for 55% 1RM (p = 0.112). Generally, compared at the same relative loads, the overhead press exhibited the greatest ACV followed by the squat, bench press, and deadlift (in order). In addition, relative strength level was inversely related to ACV at maximal loads (≥95% 1RM) for the squat, bench press, and deadlift while height was positively related to ACV at moderate loads (55% 1RM) for all lifts (p \u3c 0.05). These results suggest that the load-velocity profile is unique for each of these exercises, and that velocity ranges used for exercise prescription should be specific to the exercise. A trainee\u27s relative strength and height may be a primary influence on the ACV
Dynamical Imaging with Interferometry
By linking widely separated radio dishes, the technique of very long baseline
interferometry (VLBI) can greatly enhance angular resolution in radio
astronomy. However, at any given moment, a VLBI array only sparsely samples the
information necessary to form an image. Conventional imaging techniques
partially overcome this limitation by making the assumption that the observed
cosmic source structure does not evolve over the duration of an observation,
which enables VLBI networks to accumulate information as the Earth rotates and
changes the projected array geometry. Although this assumption is appropriate
for nearly all VLBI, it is almost certainly violated for submillimeter
observations of the Galactic Center supermassive black hole, Sagittarius A*
(Sgr A*), which has a gravitational timescale of only ~20 seconds and exhibits
intra-hour variability. To address this challenge, we develop several
techniques to reconstruct dynamical images ("movies") from interferometric
data. Our techniques are applicable to both single-epoch and multi-epoch
variability studies, and they are suitable for exploring many different
physical processes including flaring regions, stable images with small
time-dependent perturbations, steady accretion dynamics, or kinematics of
relativistic jets. Moreover, dynamical imaging can be used to estimate
time-averaged images from time-variable data, eliminating many spurious image
artifacts that arise when using standard imaging methods. We demonstrate the
effectiveness of our techniques using synthetic observations of simulated black
hole systems and 7mm Very Long Baseline Array observations of M87, and we show
that dynamical imaging is feasible for Event Horizon Telescope observations of
Sgr A*.Comment: 16 Pages, 12 Figures, Accepted for publication in Ap
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