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Radiobiological risk estimates of adverse events and secondary cancer for proton and photon radiation therapy of pediatric medulloblastoma

Introduction. The aim of this model study was to estimate and compare the risk of radiation-induced adverse late effects in pediatric patients with medulloblastoma (MB) treated with either three-dimensional conformal radiotherapy (3D CRT), inversely-optimized arc therapy (RapidArc ® (RA)) or spot-scanned intensity-modulated proton therapy (IMPT). The aim was also to find dose-volume toxicity param

Scatter and crosstalk corrections for (99m)Tc/(123)I dual-radionuclide imaging using a CZT SPECT system with pinhole collimators.

The energy spectrum for a cadmium zinc telluride (CZT) detector has a low energy tail due to incomplete charge collection and intercrystal scattering. Due to these solid-state detector effects, scatter would be overestimated if the conventional triple-energy window (TEW) method is used for scatter and crosstalk corrections in CZT-based imaging systems. The objective of this work is to develop a sc

The effect of spillover on the Granger causality test

In this paper, we investigate the properties of the Granger causality test in stationary and stable vector autoregressive models under the presence of spillover effects, that is, causality in variance. The Wald test and the WW test (the Wald test with White's proposed heteroskedasticity-consistent covariance matrix estimator imposed) are analyzed. The investigation is undertaken by using Monte Car

A conjugate gradient algorithm for the astrometric core solution of Gaia

Context. The ESA space astrometry mission Gaia, planned to be launched in 2013, has been designed to make angular measurements on a global scale with micro-arcsecond accuracy. A key component of the data processing for Gaia is the astrometric core solution, which must implement an efficient and accurate numerical algorithm to solve the resulting, extremely large least-squares problem. The Astromet

Metabolic risk factors for esophageal squamous cell carcinoma and adenocarcinoma: a prospective study of 580 000 subjects within the Me-Can project

Background: Obesity is associated with an increased risk of esophageal adenocarcinoma (EAC) and a decreased risk of esophageal squamous cell carcinoma (ESCC). However, little is known about the risk of EAC and ESCC related to other metabolic risk factors. We aimed to examine the risk of EAC and ESCC in relation to metabolic risk factors, separately and combined in a prospective cohort study. Metho

A Bio-Economic Model of Community Incentives for Wildlife Management Under CAMPFIRE

This paper formulates a bio-economic model to analyze community incentives for wildlife management under benefit-sharing programs like the Communal Areas Management Programme for Indigenous Resources (CAMPFIRE) in Zimbabwe. Three agents influence the wildlife stock: a parks agency determines hunting quotas, outside poachers hunt illegally, and a local community may choose to protect wildlife by di

One vs Three Years of Adjuvant Imatinib for Operable Gastrointestinal Stromal Tumor : A Randomized Trial

Context Adjuvant imatinib administered for 12 months after surgery has improved recurrence-free survival (RFS) of patients with operable gastrointestinal stromal tumor (GIST) compared with placebo. Objective To investigate the role of imatinib administration duration as adjuvant treatment of patients who have a high estimated risk for GIST recurrence after surgery. Design, Setting, and Patients Pa

Neonicotinoid Insecticides and Their Impacts on Bees: A Systematic Review of Research Approaches and Identification of Knowledge Gaps.

It has been suggested that the widespread use of neonicotinoid insecticides threatens bees, but research on this topic has been surrounded by controversy. In order to synthesize which research approaches have been used to examine the effect of neonicotinoids on bees and to identify knowledge gaps, we systematically reviewed research on this subject that was available on the Web of Science and PubM

Assessing atmospheric nitrogen deposition to natural and semi-natural ecosystems - Experience from Danish studies using the DAMOS

Local agricultural emissions contribute significantly to the atmospheric reactive nitrogen loads of Danish terrestrial ecosystems. In the vicinity of the sources this may be up to 6-8 kg N ha(-1) yr(-1) depending on location and ecosystem type. This contribution arises from dry deposition of gas phase ammonia derived from local livestock production. Long-range transport, however, often constitutes

Identification of a Catalytic Exosite for Complement Component C4 on the Serine Protease Domain of C1s

The classical pathway of complement is crucial to the immune system, but it also contributes to inflammatory diseases when dys-regulated. Binding of the C1 complex to ligands activates the pathway by inducing autoactivation of associated C1r, after which C1r activates C1s. C1s cleaves complement component C4 and then C2 to cause full activation of the system. The interaction between C1s and C4 inv

Adhesive and signaling mechanisms in abdominal sepsis

Sepsis is a major cause of mortality in intensive care units despite decades of scientific efforts. The lung is recognized as the most sensitive and critical organ affected by the hyper-inflammatory response in septic patients. Immune cell dysfunction develops in later phases of sepsis making patients susceptible to infections. The aim of this dissertation was to reveal pro- and anti-inflammatory

A general formula for noncohesive suspended sediment transport

A simple and robust suspended load transport formula for noncohesive sediment is presented for application to river, estuarine, and coastal environments with the use of depth-averaged models. The formula is based on an exponential profile for the concentration and assumes a constant velocity over depth to simplify the calculations. These assumptions were validated with a large data set, including

Is the commercialization of European academic R&D weak?-A critical assessment of a dominant belief and associated policy responses

There is a widespread belief that EU underperforms in the commercialization of publicly funded research and that the appropriate policy response is to transfer the ownership of intellectual property rights to Universities. This paper assesses the validity of these twin beliefs. In addressing the first, we limit ourselves to Sweden which still retains its "Teacher's Exemption" model. In spite of co

Terrestrial organic matter support of lake food webs : evidence from lake metabolism and stable hydrogen isotopes of consumers

We quantified the utilization of terrestrial organic matter (OM) in the food web of a humic lake by analyzing the metabolism and the consumers' stable isotopic (C, H, N) composition in benthic and pelagic habitats. Terrestrial OM inputs (3 g C m(-2) d(-1)) to the lake greatly exceeded autochthonous OM production (3 mg C m(-2) d(-1)) in the lake. Heterotrophic bacterial growth (19 mg C m(-2) d(-1))