2,119 research outputs found
Increasing the Reliability of Adaptive Quadrature Using Explicit Interpolants
We present two new adaptive quadrature routines. Both routines differ from
previously published algorithms in many aspects, most significantly in how they
represent the integrand, how they treat non-numerical values of the integrand,
how they deal with improper divergent integrals and how they estimate the
integration error. The main focus of these improvements is to increase the
reliability of the algorithms without significantly impacting their efficiency.
Both algorithms are implemented in Matlab and tested using both the "families"
suggested by Lyness and Kaganove and the battery test used by Gander and
Gautschi and Kahaner. They are shown to be more reliable, albeit in some cases
less efficient, than other commonly-used adaptive integrators.Comment: 32 pages, submitted to ACM Transactions on Mathematical Softwar
Cold Induction of EARLI1, a Putative Arabidopsis Lipid Transfer Protein, Is Light and Calcium Dependent
As sessile organisms, plants must adapt to their environment. One approach toward understanding this adaptation is to investigate environmental regulation of gene expression. Our focus is on the environmental regulation of EARLI1, which is activated by cold and long-day photoperiods. Cold activation of EARLI1 in short-day photoperiods is slow, requiring several hours at 4ºC to detect an increase in mRNA abundance. EARLI1 is not efficiently cold-activated in etiolated seedlings, suggesting that photomorphogenesis is necessary for its cold activation. Cold activation of EARLI1 is inhibited in the presence of the calcium channel blocker lanthanum chloride or the calcium chelator EGTA. Addition of the calcium ionophore Bay K8644 results in cold-independent activation of EARLI1. These data suggest that EARLI1 is not an immediate target of the cold response, and that calcium flux affects its expression. EARLI1 is a putative secreted protein and has motifs found in lipid transfer proteins. Over-expression of EARLI1 in transgenic plants results in reduced electrolyte leakage during freezing damage, suggesting that EARLI1 may affect membrane or cell wall stability in response to low temperature stress
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Early symptoms and sensations as predictors of lung cancer: a machine learning multivariate model.
The aim of this study was to identify a combination of early predictive symptoms/sensations attributable to primary lung cancer (LC). An interactive e-questionnaire comprised of pre-diagnostic descriptors of first symptoms/sensations was administered to patients referred for suspected LC. Respondents were included in the present analysis only if they later received a primary LC diagnosis or had no cancer; and inclusion of each descriptor required ≥4 observations. Fully-completed data from 506/670 individuals later diagnosed with primary LC (n = 311) or no cancer (n = 195) were modelled with orthogonal projections to latent structures (OPLS). After analysing 145/285 descriptors, meeting inclusion criteria, through randomised seven-fold cross-validation (six-fold training set: n = 433; test set: n = 73), 63 provided best LC prediction. The most-significant LC-positive descriptors included a cough that varied over the day, back pain/aches/discomfort, early satiety, appetite loss, and having less strength. Upon combining the descriptors with the background variables current smoking, a cold/flu or pneumonia within the past two years, female sex, older age, a history of COPD (positive LC-association); antibiotics within the past two years, and a history of pneumonia (negative LC-association); the resulting 70-variable model had accurate cross-validated test set performance: area under the ROC curve = 0.767 (descriptors only: 0.736/background predictors only: 0.652), sensitivity = 84.8% (73.9/76.1%, respectively), specificity = 55.6% (66.7/51.9%, respectively). In conclusion, accurate prediction of LC was found through 63 early symptoms/sensations and seven background factors. Further research and precision in this model may lead to a tool for referral and LC diagnostic decision-making
WRAP53 promotes cancer cell survival and is a potential target for cancer therapy
We previously identified WRAP53 as an antisense transcript that regulates the p53 tumor suppressor. The WRAP53 gene also encodes a protein essential for Cajal body formation and involved in cellular trafficking of the survival of motor neuron complex, the telomerase enzyme and small Cajal body-specific RNAs to Cajal bodies. Here, we show that the WRAP53 protein is overexpressed in a variety of cancer cell lines of different origin and that WRAP53 overexpression promotes cellular transformation. Knockdown of the WRAP53 protein triggers massive apoptosis through the mitochondrial pathway, as demonstrated by Bax/Bak activation, loss of mitochondrial membrane potential and cytochrome c release. The apoptosis induced by WRAP53 knockdown could moreover be blocked by Bcl-2 overexpression. Interestingly, human tumor cells are more sensitive to WRAP53 depletion as compared with normal human cells indicating that cancer cells in particular depends on WRAP53 expression for their survival. In agreement with this, we found that high levels of WRAP53 correlate with poor prognosis of head and neck cancer. Together these observations propose a role of WRAP53 in carcinogenesis and identify WRAP53 as a novel molecular target for a large fraction of malignancies
PSF calibration requirements for dark energy from cosmic shear
The control of systematic effects when measuring galaxy shapes is one of the
main challenges for cosmic shear analyses. In this context, we study the
fundamental limitations on shear accuracy due to the measurement of the Point
Spread Function (PSF) from the finite number of stars. In order to do that, we
translate the accuracy required for cosmological parameter estimation to the
minimum number of stars over which the PSF must be calibrated. We first derive
our results analytically in the case of infinitely small pixels (i.e.
infinitely high resolution). Then image simulations are used to validate these
results and investigate the effect of finite pixel size in the case of an
elliptical gaussian PSF. Our results are expressed in terms of the minimum
number of stars required to calibrate the PSF in order to ensure that
systematic errors are smaller than statistical errors when estimating the
cosmological parameters. On scales smaller than the area containing this
minimum number of stars, there is not enough information to model the PSF. In
the case of an elliptical gaussian PSF and in the absence of dithering, 2
pixels per PSF Full Width at Half Maximum (FWHM) implies a 20% increase of the
minimum number of stars compared to the ideal case of infinitely small pixels;
0.9 pixels per PSF FWHM implies a factor 100 increase. In the case of a good
resolution and a typical Signal-to-Noise Ratio distribution of stars, we find
that current surveys need the PSF to be calibrated over a few stars, which may
explain residual systematics on scales smaller than a few arcmins. Future
all-sky cosmic shear surveys require the PSF to be calibrated over a region
containing about 50 stars.Comment: 13 pages, 4 figures, accepted by A&
PCV46 LONG-TERM COSTS AND HEALTH OUTCOMES OF TREATING ACUTE CORONARY SYNDROME PATIENTS WITH TICAGRELOR BASED ON THE EU LABEL - COST-EFFECTIVENESS ANALYSIS BASED ON THE PLATO STUDY
Increase in mast cells and hyaluronic acid correlates to radiation-induced damage and loss of serous acinar cells in salivary glands: the parotid and submandibular glands differ in radiation sensitivity.
The detailed mechanisms which can explain the inherent radiosensitivity of salivary glands remain to be elucidated. Although DNA is the most plausible critical target for the lethal effects of irradiation, interactions with other constituents, such as cell membrane and neuropeptides, have been suggested to cause important physiological changes. Moreover, mast cells seem to be closely linked to radiation-induced pneumonitis. Therefore, in the present study the effects of fractionated irradiation on salivary glands have been assessed with special regard to the appearance of mast cells and its correlation with damage to gland parenchyma. Sprague-Dawley strain rats were unilaterally irradiated to the head and neck with the salivary glands within the radiation field. The irradiation was delivered once daily for 5 days to a total dose of 20, 35 and 45 Gy. The contralateral parotid and submandibular glands served as intra-animal controls and parallel analysis of glands was performed 2, 4, 10 or 180 days following the last radiation treatment. Morphological analysis revealed no obvious changes up to 10 days after the irradiation. At 180 days a radiation dose-dependent loss of gland parenchyma was seen, especially with regard to serious acinar cells in parotid gland and acinar cells and serous CGT (convoluted granular tubule) cells in the submandibular gland. These changes displayed a close correlation with a concomitant dose-dependent enhanced density of mast cells and staining for hyaluronic acid. This cell population seems to conform with the features of the connective tissue mast cell type. The parotid seems to be more sensitive to irradiation than the submandibular gland. Thus, the present results further strengthen the role of and the potential interaction of mast cells with radiation-induced tissue injury and alterations in normal tissue integrity
Who Is In Charge, and Who Should Be? The Disciplinary Role of the Commander in Military Justice Systems
BackgroundStandard therapy for newly diagnosed glioblastoma is radiotherapy plus temozolomide. In this phase 3 study, we evaluated the effect of the addition of bevacizumab to radiotherapy-temozolomide for the treatment of newly diagnosed glioblastoma. MethodsWe randomly assigned patients with supratentorial glioblastoma to receive intravenous bevacizumab (10 mg per kilogram of body weight every 2 weeks) or placebo, plus radiotherapy (2 Gy 5 days a week; maximum, 60 Gy) and oral temozolomide (75 mg per square meter of body-surface area per day) for 6 weeks. After a 28-day treatment break, maintenance bevacizumab (10 mg per kilogram intravenously every 2 weeks) or placebo, plus temozolomide (150 to 200 mg per square meter per day for 5 days), was continued for six 4-week cycles, followed by bevacizumab monotherapy (15 mg per kilogram intravenously every 3 weeks) or placebo until the disease progressed or unacceptable toxic effects developed. The coprimary end points were investigator-assessed progression-free survival and overall survival. ResultsA total of 458 patients were assigned to the bevacizumab group, and 463 patients to the placebo group. The median progression-free survival was longer in the bevacizumab group than in the placebo group (10.6 months vs. 6.2 months; stratified hazard ratio for progression or death, 0.64; 95% confidence interval [CI], 0.55 to 0.74; P<0.001). The benefit with respect to progression-free survival was observed across subgroups. Overall survival did not differ significantly between groups (stratified hazard ratio for death, 0.88; 95% CI, 0.76 to 1.02; P=0.10). The respective overall survival rates with bevacizumab and placebo were 72.4% and 66.3% at 1 year (P=0.049) and 33.9% and 30.1% at 2 years (P=0.24). Baseline health-related quality of life and performance status were maintained longer in the bevacizumab group, and the glucocorticoid requirement was lower. More patients in the bevacizumab group than in the placebo group had grade 3 or higher adverse events (66.8% vs. 51.3%) and grade 3 or higher adverse events often associated with bevacizumab (32.5% vs. 15.8%). ConclusionsThe addition of bevacizumab to radiotherapy-temozolomide did not improve survival in patients with glioblastoma. Improved progression-free survival and maintenance of baseline quality of life and performance status were observed with bevacizumab; however, the rate of adverse events was higher with bevacizumab than with placebo.
Music
This is an invited contribution to the SAGE Encyclopedia of Contemporary Early Childhood Education concerning music
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