3,662 research outputs found
Validity of very short answer versus single best answer questions for undergraduate assessment
Background Single Best Answer (SBA) questions are widely used in undergraduate and postgraduate medical examinations. Selection of the correct answer in SBA questions may be subject to cueing and therefore might not test the student’s knowledge. In contrast to this artificial construct, doctors are ultimately required to perform in a real-life setting that does not offer a list of choices. This professional competence can be tested using Short Answer Questions (SAQs), where the student writes the correct answer without prompting from the question. However, SAQs cannot easily be machine marked and are therefore not feasible as an instrument for testing a representative sample of the curriculum for a large number of candidates. We hypothesised that a novel assessment instrument consisting of very short answer (VSA) questions is a superior test of knowledge than assessment by SBA. Methods We conducted a prospective pilot study on one cohort of 266 medical students sitting a formative examination. All students were assessed by both a novel assessment instrument consisting of VSAs and by SBA questions. Both instruments tested the same knowledge base. Using the filter function of Microsoft Excel, the range of answers provided for each VSA question was reviewed and correct answers accepted in less than two minutes. Examination results were compared between the two methods of assessment. Results Students scored more highly in all fifteen SBA questions than in the VSA question format, despite both examinations requiring the same knowledge base. Conclusions Valid assessment of undergraduate and postgraduate knowledge can be improved by the use of VSA questions. Such an approach will test nascent physician ability rather than ability to pass exams
A New Concept of Transonic Galactic Outflows in a Cold Dark Matter Halo with a Central Super-Massive Black Hole
We study fundamental properties of isothermal, steady and spherically
symmetric galactic outflow in the gravitational potential of a cold dark matter
halo and a central super-massive black hole. We find that there are two
transonic solutions having different properties: each solution is mainly
produced by the dark matter halo and the super-massive black hole,
respectively. Furthermore, we apply our model to the Sombrero galaxy. In this
galaxy, Chandra X-ray observatory detected the diffuse hot gas as the trace of
galactic outflows while the star-formation rate is low and the observed gas
density distribution presumably indicates the hydrostatic equilibrium. To solve
this discrepancy, we propose a solution that this galaxy has a transonic
outflow, however, the transonic point forms in a very distant region from the
galactic center (? 127 kpc). In this slowly accelerated transonic
outflow, the outflow velocity is less than the sound velocity for most of the
galactic halo. Since the gas density distribution in this subsonic region is
similar to the hydrostatic one, it is difficult to distinguish the wide
subsonic region from hydrostatic state. Such galactic outflows are dfferent
from the conventional supersonic outflows observed in star-forming galaxies.Comment: 7 pages, 3 figures, accepted for publication in JPS Conference
Proceedings. arXiv admin note: substantial text overlap with arXiv:1405.345
Quality of eggs produced from wild and captive spawners of Penaeus Indicus H. Milne Edwards and their bacterial load
The seeds of Penaeus indicus H. Milne Edwards were
produced following the modified Galveston system
at a hatchery located at Narakkal near Cochin, India.
Unilaterally eyestalk-ablated wild females were used
for seed production. Some adult prawns collected
from grow-out ponds attached to the hatchery were
also used for breeding purposes. In all, 20 spawnings
were observed in the present study. Poor-quality
eggs and abnormal nauplii were observed, usually
from the pond-reared eyestalk-ablated females
during the period of investigation. The present study
was carried out to describe different types of eggs
based on morphology and to determine the bacterial
load of eggs and its relationship with hatching rate
On the little known species of threadfin breams Nemipterus mesoprion (Bleeker) and Nemipterus delagoae (Smith)
Among the fish species of the family Nemipteridae, the two little known species, namely, Nemipterus mesoprion (Bleeker) and Nemipterus delagoae (Smith) are recorded from the Cochin waters. Nemipterus mesoprion is a new distributional record from the west coast of India. N. delagoae is described with adequate numbers of specimen for the first time from Indian waters. Moreover, the results of the present study show that the colour of the viscera, the number of pyloric caeca and the gill rakers can also be used for the diagnosis of the species of the genus Nemipterus. The affinity of the above species with other related species of the genus Nemipterus and their geographical distribution are presented
Exchange rate behavior with negative interest rates: Some early negative observations
This paper examines exchange rate behavior during the recent period with negative nominal interest rates. We use a daily panel of data on 61 currencies from January 2010 through May 2016, during which five economies - Denmark, the European Economic and Monetary Union, Japan, Sweden, and Switzerland - experienced negative nominal interest rates. We examine both effective exchange rates and bilateral rates; the latter typically measured against the Swiss franc since Switzerland has had the longest period of negative nominal rates. We examine exchange rate volatility, exchange rate changes, deviations from uncovered interest parity, and profits from the carry trade. We find that negative interest rates seem to have little effect on observable exchange rate behavior
Poet R. Meenakshi’s Social Progress
Writers in their works highlights many events related to relationship system with the hope that the people in the society should live in harmony. Similarly, R. Meenakshi's poems is about the inequalities among the people, social concern, women's progress, individual human morality, self-sacrifice and humanity. There is nothing equivalent or comparable to the love and affection of a mother. Poets play an important role in such social progress. The article explores the strategies that Meenakshi put forward in the human society by removing the ignorance and ups and downs embedded among the people
Aquaculture and Marine Biotechnology Programme in India
Marine biotechnology has been a major focus world-wide through bio-discovery of marine microbes, invertebrates, micro-algae and macro-algae. In the commercial production of bio-active molecules and pharmaceuticals it plays a pivotal role. The global market for products from marine biotechnology is expected to reach over US$ 4 billion by 2015 and therefore marine bio-resources emerging with a lot of scope for the health and well being of aquacultur
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