1,302 research outputs found
Impacts of Scale on Geographic Analysis of Health Data: An Example of Obesity Prevalence
published_or_final_versio
Spare-Parts Technique for Concurrent Treatment of Ectrodactyly of the Feet and Syndactyly of the Hands in a 2-Year-Old Boy: A Case Report
Syndactyly is the most frequently occurring congenital malformation of the limbs. Although common, few studies have reported treating syndactyly using Z-plasty with and without full-thickness grafting. We present a 2-year-old boy who presented to our clinic with ectrodactyly of the feet and simple complete syndactyly of two fingers on each hand. After ectrodactyly reconstruction, we used the excess foot skin to cover finger defects. The patient recovered well postoperatively, with matching skin and no trouble with hair growth. Use of a spare-parts technique can help avoid complications associated with harvesting grafts from other donor sites. The results reinforce the importance of coordinating reconstructive techniques when necessary for operative treatment of syndactyly of the hands
Suturing Workshop for Third-Year Medical Students: A Modern Educational Approach
Background: This study sought to determine if developing suturing workshops based on modern educational theory would lead to a significant increase in third-year medical students’ confidence and preparedness as compared to before the workshop.
Methods: A group of pre-clinical, third-year medical students (n = 20) were voluntarily recruited. The workshop consisted of an interactive didactic session, a hands-on suturing session, and a question-answer session with surgeons. The nine-point Likert scale surveys were given pre-and post-workshop to 17 participants. Total scores of “confidence” and “preparedness” were analyzed using the Student t-test. Results of Q-Q plot and normality tests were used to validate the normality assumption. All analysis was conducted using SAS Software 9.4 (Cary, North Carolina).
Results: A statistically significant increase in both confidence and preparedness was found between results of pre- and post-workshop surveys. Average total scores in confidence increased by 19.7 points, from 19.3 to 39 (95% CI: 15.0-24.4; P value \u3c 0.001). For scores in preparedness, the total score increased by an average of 18.4 points, from 22.8 to 41.2 (95% CI: 14.1-22.8; P value \u3c 0.001).
Conclusions: These findings suggest that a structured course based on modern educational theory can increase both the confidence and preparedness of third-year medical students who are matriculating into their hospitalbased clerkships
Simplifying asteroseismic analysis of solar-like oscillators:An application of principal component analysis for dimensionality reduction
Vascular endothelial growth factor (VEGF) expression is a prognostic factor for radiotherapy outcome in advanced carcinoma of the cervix
The aim of the study was to evaluate VEGF expression in tumour biopsies as a prognostic factor for radiotherapy outcome in advanced carcinoma of the cervix. A retrospective study was carried out on 100 patients. Pre-treatment tumour VEGF expression was examined immunohistochemically in formalin-fixed, paraffin-embedded biopsies using a widely available commercial antibody. A semi-quantitative analysis was made using a scoring system of 0, 1, 2, and 3, for increasing intensity of staining. High VEGF expression was associated with a poor prognosis. A univariate log rank analysis found a significant relationship with overall survival (P = 0.0008) and metastasis-free survival (P = 0.0062), but not local control (P = 0.23). There was no correlation between VEGF expression and disease stage, tumour differentiation, patient age, or tumour radiosensitivity (SF2). In a Cox multivariate analysis of survival VEGF expression was the most significant independent prognostic factor (P = 0.001). After allowing for VEGF only SF2 was a significant prognostic factor (P = 0.003). In conclusion, immunohistochemical analysis of VEGF expression is a highly significant and independent prognostic indicator of overall and metastasis-free survival for patients treated with radiotherapy for advanced carcinoma of the cervix. It is also a rapid and easy method that could be used in the clinical setting, to identify patients at high risk of failure with conventional radiotherapy who may benefit from novel approaches or chemoradiotherapy. © 2000 Cancer Research Campaig
Simplifying asteroseismic analysis of solar-like oscillators: An application of principal component analysis for dimensionality reduction
The asteroseismic analysis of stellar power density spectra is often
computationally expensive. The models used in the analysis may use several
dozen parameters to accurately describe features in the spectra caused by
oscillation modes and surface granulation. Many parameters are often highly
correlated, making the parameter space difficult to quickly and accurately
sample. They are, however, all dependent on a smaller set of parameters, namely
the fundamental stellar properties. We aim to leverage this to simplify the
process of sampling the model parameter space for the asteroseismic analysis of
solar-like oscillators, with an emphasis on mode identification. Using a large
set of previous observations, we applied principal component analysis to the
sample covariance matrix to select a new basis on which to sample the model
parameters. Selecting the subset of basis vectors that explains the majority of
the sample variance, we redefine the model parameter prior probability density
distributions in terms of a smaller set of latent parameters. We are able to
reduce the dimensionality of the sampled parameter space by a factor of two to
three. The number of latent parameters needed to accurately model the stellar
oscillation spectra cannot be determined exactly but is likely only between
four and six. Using two latent parameters, the method is able to describe the
bulk features of the oscillation spectrum, while including more latent
parameters allows for a frequency precision better than of the
small frequency separation for a given target. We find that sampling a
lower-rank latent parameter space still allows for accurate mode identification
and parameter estimation on solar-like oscillators over a wide range of
evolutionary stages. This allows for the potential to increase the complexity
of spectrum models without a corresponding increase in computational expense.Comment: Accepted for publication in Astronomy & Astrophysics. 11 pages. 10
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Pretreatment apoptosis in carcinoma of the cervix correlates with changes in tumour oxygenation during radiotherapy
A relationship between hypoxia and apoptosis has been identified in vitro and in experimental tumours. The aim of this study was to investigate the relationship between apoptosis, hypoxia and the change in oxygenation during radiotherapy in human squamous cell carcinoma of the cervix. Forty-two patients with locally advanced disease underwent pretreatment evaluation of tumour oxygenation using an Eppendorf computerized microneedle electrode. Twenty-two of these patients also had a second evaluation of tumour oxygenation after receiving 40–45 Gy external beam radiotherapy. Paraffin-embedded histological sections were obtained from random pretreatment biopsies for all 42 patients. Apoptotic index (AI) was quantified by morphology on TUNEL stained sections. No correlation was found between pretreatment measures of AI and either the median pO2(r = 0.12, P = 0.44) or percentage of values < 5 mmHg (r = –0.02, P = 0.89). A significant positive correlation was found between AI and the change in tumour oxygenation (ratio of pre:post-treatment % values < 5 mmHg) following radiotherapy (r = 0.61, P = 0.002). The lack of correlation between apoptosis and hypoxia may occur because the Eppendorf measures both acute and chronic hypoxia, and the relative ability of acute hypoxia to induce apoptosis is unknown. These results indicate that cell death via apoptosis may be a mechanism of tumour reoxygenation during radiotherapy. © 2000 Cancer Research Campaig
Inferring Core-Collapse Supernova Physics with Gravitational Waves
Stellar collapse and the subsequent development of a core-collapse supernova
explosion emit bursts of gravitational waves (GWs) that might be detected by
the advanced generation of laser interferometer gravitational-wave
observatories such as Advanced LIGO, Advanced Virgo, and LCGT. GW bursts from
core-collapse supernovae encode information on the intricate multi-dimensional
dynamics at work at the core of a dying massive star and may provide direct
evidence for the yet uncertain mechanism driving supernovae in massive stars.
Recent multi-dimensional simulations of core-collapse supernovae exploding via
the neutrino, magnetorotational, and acoustic explosion mechanisms have
predicted GW signals which have distinct structure in both the time and
frequency domains. Motivated by this, we describe a promising method for
determining the most likely explosion mechanism underlying a hypothetical GW
signal, based on Principal Component Analysis and Bayesian model selection.
Using simulated Advanced LIGO noise and assuming a single detector and linear
waveform polarization for simplicity, we demonstrate that our method can
distinguish magnetorotational explosions throughout the Milky Way (D <~ 10kpc)
and explosions driven by the neutrino and acoustic mechanisms to D <~ 2kpc.
Furthermore, we show that we can differentiate between models for rotating
accretion-induced collapse of massive white dwarfs and models of rotating iron
core collapse with high reliability out to several kpc.Comment: 22 pages, 9 figure
Inhibition of IRE1 alpha RNase activity reduces NLRP3 inflammasome assembly and processing of pro-IL1 beta (vol 77, pg 568, 2019)
Inhibition of IRE1 alpha RNase activity reduces NLRP3 inflammasome assembly and processing of pro-IL1 beta
The inflammasome is a multiprotein complex assembled in response to Pathogen Associated Molecular Patterns (PAMPs) and Danger Associated Molecular Patterns (DAMPS). Inflammasome activation occurs through a two-step mechanism, with the first signal facilitating priming of inflammasome components while the second signal triggers complex assembly. Once assembled, the inflammasome recruits and activates pro-caspase-1, which in turn processes pro-interleukin (IL)-18 and pro-IL-1 beta into their bio-active forms. Owing to its key role in the regulation of innate immune responses, the inflammasome has emerged as a therapeutic target for the treatment of inflammatory conditions. In this study we demonstrate that IRE1 alpha, a key component of the Unfolded Protein Response, contributes to assembly of the NLRP3 inflammasome. Blockade of IRE1 alpha RNase signaling lowered NLRP3 inflammasome assembly, caspase-1 activation and pro-IL-1 beta processing. These results underscore both the importance and potential therapeutic relevance of targeting IRE1 alpha signaling in conditions of excessive inflammasome formation
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