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On being a mentor
This article explores issues relating to mentoring students, particularly ophthalmic nursing students. It highlights the importance of mentorship in learning in practice, which in turn is critical to students' education in a competency-based profession. It considers the factors essential in successful mentoring, including two-way feedback, and the importance of mentors understanding the nature of the psychological processes involved and how to assess students' learning and competencies. It also highlights the crucial gate-keeping role of mentors in ensuring that students are fit to practise, and the importance of nurse mentors themselves being fit to practise
IX Draconis - a curious ER UMa-type dwarf nova
We report results of an extensive world-wide observing campaign devoted to a
very active dwarf nova star - IX Draconis. We investigated photometric
behaviour of the system to derive its basic outburst properties and understand
peculiarities of IX Dra as well as other active cataclysmic variables, in
particular dwarf novae of the ER Uma-type. In order to measure fundamental
parameters of the system, we carried out analyses of the light curve, O-C
diagram, and power spectra. During over two months of observations we detected
two superoutbursts and several normal outbursts. The V magnitude of the star
varied in the range 14.6 - 18.2 mag. Superoutbursts occur regularly with the
supercycle length of 58.5+/-0.5 d. When analysing data over the past 20 years,
we found that the supercycle length is increasing at a rate of P_dot = 1.8 *
10^{-3}. Normal outbursts appear to be irregular, with typical occurrence times
in the range 3.1 - 4.1 d. We detected a double-peaked structure of superhumps
during superoutburst, with the secondary maximum becoming dominant near the end
of the superoutburst. The mean superhump period observed during superoutbursts
equals 0.066982(36) d, which is constant over the last two decades of
observations. Based on the power spectrum analysis, the evaluation of the
orbital period was problematic. We found two possible values: the first one,
0.06641(3) d, which is in agreement with previous studies and our O-C analysis
(0.06646(2) d), and the second one, 0.06482(3) d, which is less likely. The
evolutionary status of the object depends dramatically on the choice between
these two values. A spectroscopic determination of the orbital period is
needed. We updated available information on ER UMa-type stars and present a new
set of their basic statistics. Thereby, we provide evidence that this class of
stars is not uniform.Comment: Accepted for publication in MNRAS; 15 pages, 15 figures, 6 tables;
typo correcte
HT Cas - eclipsing dwarf nova during its superoutburst in 2010
We present results of a world-wide observing campaign of the eclipsing dwarf
nova - HT Cas during its superoutburst in November 2010. Using collected data
we were able to conduct analysis of the light curves and we calculated
diagrams.
The CCD photometric observations enabled us to derive the superhump period
and with the timings of eclipses the orbital period was calculated. Based on
superhump and orbital period estimations the period excess and mass ratio of
the system were obtained
Stroke-related Changes in Neuromuscular Fatigue of the Hip Flexors and Functional Implications
Objective: The aim of this study was to compare stroke-related changes in hip flexor neuromuscular fatigue of the paretic leg during a sustained isometric submaximal contraction with those of the nonparetic leg and controls and to correlate fatigue with clinical measures of function.
Design: Hip torques were measured during a fatiguing hip flexion contraction at 20% of the hip flexion maximal voluntary contraction in the paretic and nonparetic legs of 13 people with chronic stroke and 10 age-matched controls. In addition, the participants with stroke performed a fatiguing contraction of the paretic leg at the absolute torque equivalent to 20% maximal voluntary contraction of the nonparetic leg and were tested for self-selected walking speed (10-m Walk Test) and balance (Berg).
Results: When matching the nonparetic target torque, the paretic hip flexors had a shorter time to task failure compared with the nonparetic leg and controls (P \u3c 0.05). The time to failure of the paretic leg was inversely correlated with the reduction of hip flexion maximal voluntary contraction torque. Self-selected walking speed was correlated with declines in torque and steadiness. Berg-Balance scores were inversely correlated with the force fluctuation amplitude.
Conclusions: Fatigue and precision of contraction are correlated with walking function and balance after stroke
MN Draconis - peculiar, active dwarf nova in the period gap
Context: We present results of an extensive world-wide observing campaign of
MN Draconis.
Aims: MN Draconis is a poorly known active dwarf nova in the period gap and
is one of the only two known cases of period gap SU UMa objects showing the
negative superhumps. Photometric behaviour of MN Draconis poses a challenge for
existing models of the superhump and superoutburst mechanisms. Therefore,
thorough investigation of peculiar systems, such as MN Draconis, is crucial for
our understanding of evolution of the close binary stars.
Methods: To measure fundamental parameters of the system, we collected
photometric data in October 2009, June-September 2013 and June-December 2015.
Analysis of the light curves, diagrams and power spectra was carried out.
Results: During our three observational seasons we detected four
superoutburts and several normal outbursts. Based on the two consecutive
superoutbursts detected in 2015, the supercycle length was derived P_sc = 74
+/- 0.5 days and it has been increasing with a rate of P_dot = 3.3 x 10^(-3)
during last twelve years. Based on the positive and negative superhumps we
calculated the period excess epsilon = 5.6% +/- 0.1%, the period deficit
epsilon_ = 2.5% +/- 0.6%, and in result, the orbital period P_orb = 0.0994(1)
days (143.126 +/- 0.144 min). We updated the basic light curve parameters of MN
Draconis.
Conclusions: MN Draconis is the first discovered SU UMa system in the period
gap with increasing supercycle length.Comment: 14 pages, 20 figures, 8 tables, accepted for publication in Astronomy
and Astrophysic
How to reduce the number of rating scale items without predictability loss?
Rating scales are used to elicit data about qualitative entities (e.g.,
research collaboration). This study presents an innovative method for reducing
the number of rating scale items without the predictability loss. The "area
under the receiver operator curve method" (AUC ROC) is used. The presented
method has reduced the number of rating scale items (variables) to 28.57\%
(from 21 to 6) making over 70\% of collected data unnecessary.
Results have been verified by two methods of analysis: Graded Response Model
(GRM) and Confirmatory Factor Analysis (CFA). GRM revealed that the new method
differentiates observations of high and middle scores. CFA proved that the
reliability of the rating scale has not deteriorated by the scale item
reduction. Both statistical analysis evidenced usefulness of the AUC ROC
reduction method.Comment: 14 pages, 5 figure
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