16,820 research outputs found
Improving the viability of mental models held by novice programmers
Recent research has found that many novice programmers often hold non-viable mental models of basic programming concepts such as assignment and object reference. This paper proposes a constructivist-based teaching model, integrating a cognitive conflict strategy with program visualization, with the aim of improving novice programmers’ mental models. The results of a preliminary empirical study suggest that, for the relatively straightforward concept of assignment, tight integration of program visualization with a cognitive conflict event that highlights a student’s inappropriate understanding can help improve students’ non-viable mental models. 14 out of 18 participants who held non-viable mental models of the assignment process successfully changed their model to be viable as a result of the proposed teaching model
A novel approach to latent fingermark detection using aptamer-based reagents
University of Technology, Sydney. Faculty of Science.Research into latent fingermark detection and visualisation has taken many paths over the years as researchers and practitioners explore numerous methods to improve existing reagents. The majority of past research has resulted in providing small, incremental improvements to existing techniques. Currently, some researchers have opted to seek more transformational improvements in detection sensitivity, selectivity and visualisation. One such area being investigated is utilising immunology to target proteins, amino acids and drug metabolites in the latent fingermark deposit. Research to date has indicated that antibodies have great potential in providing these transformational improvements due to their ability to bind to certain fingermark components with high sensitivity and selectivity.
Following on from the antibody research, aptamers have been highlighted as the next potential immunogenic technique for several reasons, including reduced health and safety issues, lower cost, greater sensitivity and selectivity, and ease of design and versatility. Aptamers are specifically selected oligonucleotides comprised of either ribonucleic acid (RNA) or single-stranded deoxyribonucleic acid (ssDNA). Due to the selection strategies employed, aptamers can be designed to target most molecules and bind to them with detection limits in the sub-micromolar to nanomolar ranges. Although aptamers have been successfully used in a variety of highly sensitive and selective detection devices, they have not been investigated for use in the detection and visualisation of latent fingermarks prior to this project.
Initially, this project focussed on aptamers targeting amino acids as a means of visualising latent fingermarks. However, it was found that strong, non-specific interactions occurred with both the aptamer and the fluorescent tag, resulting in a lack of success with this approach.
In order to address these issues, aptamers selected to the protein lysozyme were used on fingermarks placed on both PVDF and plain white copier paper. Lysozyme was selected as it was found to be a component in human sweat, while aptamers selected to lysozyme, with binding affinities in the nanomolar range were available. It was found that the aptamer-based reagents possessed high levels of sensitivity with the clear detection of lysozyme at very low concentrations (1 ng). Latent fingermarks from various donors were able to be detected on both substrates, with primary and secondary level detail being clearly visible. Results, however, were very inconsistent, with marks older than a couple of days being difficult to detect. This was found to be due to the degradation of lysozyme in the latent fingermark. Unfortunately, aptamers to other, possibly more suitable, fingermark components that would circumvent this problem were not available for this project. Despite the difficulties encountered, this project has, for the first time, demonstrated the potential of detecting and visualising latent fingermarks with an aptamer-based reagent. The study has laid the groundwork for future successful investigations that exploit the benefits of aptamers while overcoming the limitations identified in this project
A collaborative approach to learning programming: a hybrid learning model
The use of cooperative working as a means of developing collaborative skills has been recognised as vital in programming education. This paper presents results obtained from preliminary work to investigate the effectiveness of Pair Programming as a collaborative learning strategy and also its value towards improving programming skills within the laboratory. The potential of Problem Based Learning as a means of further developing cooperative working skills along with problem solving skills is also examined and a hybrid model encompassing both strategies outlined
Admission predictors for success in a mathematics graduate program
There are many factors that can influence the outcome for students in a
mathematics PhD program: bachelor's GPA (BGPA), bachelor's major, GRE scores,
gender, Under-Represented Minority (URM) status, institution tier, etc. Are
these variables equally important predictors of a student's likelihood of
succeeding in a math PhD program? In this paper, we present and analyze
admission data of students from different groups entering a math PhD program at
a southern California university. We observe that some factors correlate with
success in the PhD program (defined as obtaining a PhD degree within a
time-limit). According to our analysis, GRE scores correlate with success, but
interestingly, the verbal part of the GRE score has a higher predictive power
compared to the quantitative part. Further, we observe that undergraduate
student GPA does not correlate with success (there is even a slight negative
slope in the relationship between GPA and the probability of success). This
counterintuitive observation is explained once undergraduate institutions are
separated by tiers: students from "higher tiers" have undergone a more rigorous
training program; they on average have a slightly lower GPA but run a slightly
higher probability to succeed. Finally, a gender gap is observed in the
probability to succeed with female students having a lower probability to
finish with a PhD despite the same undergraduate performance, compared to
males. This gap is reversed if we only consider foreign graduate students. It
is our hope that this study will encourage other universities to perform
similar analyses, in order to design better admission and retention strategies
for Math PhD programs.Comment: 13 pages, 11 figures, 4 table
An evaluation of the Change Up programme
This report presents the findings of an evaluation of the Change Up programme
Laryngological presentations and patient-reported outcome measures in Ehlers-Danlos syndrome
OBJECTIVE:
This study aimed to characterise the laryngological presentations of Ehlers–Danlos syndrome and
conduct a preliminary exploration of patient-reported outcome measures.
METHODS:
This paper describes a retrospective case series of patients with Ehlers–Danlos syndrome seen by
the senior author between 2005 and 2019. A literature review was conducted to summarise the existing
findings.
RESULTS:
Twenty-one patients met the inclusion criteria. All reported symptoms were grouped; this showed
that swallowing, voice and hyolaryngeal skeletal complex problems were commonest. Patient-reported
outcome measures were available for eight patients, which showed large variations in: the Reflux Severity
Index (median = 25.5; range = 0–33), Eating Assessment Tool score (median = 21.5; range = 0–35) and
Voice Handicap Index (median = 21.5; range = 0–104). Twelve studies met our literature review inclusion
criteria, involving at least 91 patients with laryngological presentations of Ehlers–Danlos syndrome.
CONCLUSION:
Ehlers–Danlos syndrome patients experience musculoskeletal issues, which in the throat
manifest as hyolaryngeal skeletal complex problems. Future studies with larger patient numbers are required
to validate laryngological patient-reported outcome measure tools in Ehlers–Danlos syndrome
Deletion of annexin 2 light chain p11 in nociceptors causes deficits in somatosensory coding and pain behavior
The S100 family protein p11 (S100A10, annexin 2 light chain) is involved in the trafficking of the voltage-gated sodium channel Na(V)1.8, TWIK-related acid-sensitive K+ channel (TASK-1), the ligand-gated ion channels acid-sensing ion channel 1a (ASIC1a) and transient receptor potential vanilloid 5/6 (TRPV5/V6), as well as 5-hydroxytryptamine receptor 1B (5-HT1B), a G-protein-coupled receptor. To evaluate the role of p11 in peripheral pain pathways, we generated a loxP-flanked (floxed) p11 mouse and used the Cre-loxP recombinase system to delete p11 exclusively from nociceptive primary sensory neurons in mice. p11-null neurons showed deficits in the expression of NaV1.8, but not of annexin 2. Damage-sensing primary neurons from these animals show a reduced tetrodotoxin-resistant sodium current density, consistent with a loss of membrane-associated NaV1.8. Noxious coding in wide-dynamic-range neurons in the dorsal horn was markedly compromised. Acute pain behavior was attenuated in certain models, but no deficits in inflammatory pain were observed. A significant deficit in neuropathic pain behavior was also apparent in the conditional-null mice. These results confirm an important role for p11 in nociceptor function
Seesaw Neutrino Mass and New U(1) Gauge Symmetry
The three electroweak doublet neutrinos of the Standard
Model may acquire small seesaw masses, using either three Majorana fermion
singlets or three Majorana fermion triplets .
It is well-known that the former accommodates the U(1) gauge symmetry . It
has also been shown some years ago that the latter supports a new
gauge symmetry. Here we study two variations of this , one for two
and one , the other for one and two . Phenomenological
consequences are discussed.Comment: 16 pages, 3 figures, LaTex, 2 eps files,text adde
The Digital Flynn Effect: Complexity of Posts on Social Media Increases over Time
Parents and teachers often express concern about the extensive use of social
media by youngsters. Some of them see emoticons, undecipherable initialisms and
loose grammar typical for social media as evidence of language degradation. In
this paper, we use a simple measure of text complexity to investigate how the
complexity of public posts on a popular social networking site changes over
time. We analyze a unique dataset that contains texts posted by 942, 336 users
from a large European city across nine years. We show that the chosen
complexity measure is correlated with the academic performance of users: users
from high-performing schools produce more complex texts than users from
low-performing schools. We also find that complexity of posts increases with
age. Finally, we demonstrate that overall language complexity of posts on the
social networking site is constantly increasing. We call this phenomenon the
digital Flynn effect. Our results may suggest that the worries about language
degradation are not warranted
Analytical solution of the tooling/workpiece contact interface shape during a flow forming operation
Flow forming involves complicated tooling/workpiece interactions. Purely
analytical models of the tool contact area are difficult to formulate,
resulting in numerical approaches that are case-specific. Provided are the
details of an analytical model that describes the steady-state
tooling/workpiece contact area allowing for easy modification of the dominant
geometric variables. The assumptions made in formulating this analytical model
are validated with experimental results attained from physical modelling. The
analysis procedure can be extended to other rotary forming operations such as
metal spinning, shear forming, thread rolling and crankshaft fillet rolling.Comment: 28 pages, 11 figure
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