The impact of new Geant4-DNA cross section models on electron track structure simulations in liquid water

Abstract Magnetic resonance-guided radiotherapy (MRgRT) has been developed and installed in recent decades for external radiotherapy in several clinical facilities. The Lorentz force modulates dose distribution by charged particles in MRgRT; however, the impact by this force on low-energy electron track structure and early DNA damage induction remain unclear. In this study, we estimated features of electron track structure and biological effects in a static magnetic field (SMF) using a general-purpose Monte Carlo code, Particle and Heavy Ion Transport code System (PHITS) that enables us to simulate low-energy electrons down to 1 meV by track-structure mode. The macroscopic dose distributions by electrons above approximately 300 keV initial energy in liquid water are changed by both perpendicular and parallel SMFs against the incident direction, indicating that the Lorentz force plays an important role in calculating dose within tumours. Meanwhile, DNA damage estimation based on the spatial patterns of atomic interactions indicates that the initial yield of DNA double-strand breaks (DSBs) is independent of the SMF intensity. The DSB induction is predominantly attributed to the secondary electrons below a few tens of eV, which are not affected by the Lorentz force. Our simulation study suggests that treatment planning for MRgRT can be made with consideration of only changed dose distribution.

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Charged current Drell-Yan production at N3LO

Journal of High Energy Physics ◽

10.1007/jhep11(2020)143 ◽

2020 ◽

Vol 2020 (11) ◽

Cited By ~ 1

Author(s):

Claude Duhr ◽

Falko Dulat ◽

Bernhard Mistlberger

Keyword(s):

Cross Section ◽

Cross Sections ◽

Production Cross Section ◽

Production Cross ◽

Hadron Collider ◽

Charge Asymmetry ◽

Charged Current ◽

Leading Order ◽

Neutrino Pair ◽

The Impact

Abstract We present the production cross section for a lepton-neutrino pair at the Large Hadron Collider computed at next-to-next-to-next-to-leading order (N3LO) in QCD perturbation theory. We compute the partonic coefficient functions of a virtual W± boson at this order. We then use these analytic functions to study the progression of the perturbative series in different observables. In particular, we investigate the impact of the newly obtained corrections on the inclusive production cross section of W± bosons, as well as on the ratios of the production cross sections for W+, W− and/or a virtual photon. Finally, we present N3LO predictions for the charge asymmetry at the LHC.

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Mechanical Properties of Spruce Wood Extracted from GLT Beams Loaded by Fire

Sustainability ◽

10.3390/su13105494 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5494

Author(s):

Lucie Kucíková ◽

Michal Šejnoha ◽

Tomáš Janda ◽

Jan Sýkora ◽

Pavel Padevět ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Cross Section ◽

Negative Impact ◽

Tensile Tests ◽

Thermal Recovery ◽

Bending Test ◽

Small Scale ◽

Spruce Wood ◽

The Impact

Heating wood to high temperature changes either temporarily or permanently its physical properties. This issue is addressed in the present contribution by examining the effect of high temperature on residual mechanical properties of spruce wood, grounding on the results of full-scale fire tests performed on GLT beams. Given these tests, a computational model was developed to provide through-thickness temperature profiles allowing for the estimation of a charring depth on the one hand and on the other hand assigning a particular temperature to each specimen used subsequently in small-scale tensile tests. The measured Young’s moduli and tensile strengths were accompanied by the results from three-point bending test carried out on two groups of beams exposed to fire of a variable duration and differing in the width of the cross-section, b=100 mm (Group 1) and b=160 mm (Group 2). As expected, increasing the fire duration and reducing the initial beam cross-section reduces the residual bending strength. A negative impact of high temperature on residual strength has also been observed from simple tensile tests, although limited to a very narrow layer adjacent to the charring front not even exceeding a typically adopted value of the zero-strength layer d0=7 mm. On the contrary, the impact on stiffness is relatively mild supporting the thermal recovery property of wood.

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MBL drizzle properties and their impact on cloud property retrievals

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-4307-2015 ◽

2015 ◽

Vol 8 (4) ◽

pp. 4307-4323

Author(s):

P. Wu ◽

X. Dong ◽

B. Xi

Keyword(s):

Liquid Water ◽

Cloud Droplet ◽

Number Concentration ◽

Effective Radius ◽

Liquid Water Path ◽

Water Path ◽

Cloud Property ◽

Annual Means ◽

Mean Differences ◽

The Impact

Abstract. In this study, we retrieve and document drizzle properties, and investigate the impact of drizzle on cloud property retrievals from ground-based measurements at the ARM Azores site from June 2009 to December 2010. For the selected cloud and drizzle samples, the drizzle occurrence is 42.6% with a maximum of 55.8% in winter and a minimum of 35.6% in summer. The annual means of drizzle liquid water path LWPd, effective radius rd, and number concentration Nd for the rain (virga) samples are 5.48 (1.29) g m−2, 68.7 (39.5) μm, and 0.14 (0.38) cm−3. The seasonal mean LWPd values are less than 4% of the MWR-retrieved LWP values. The annual mean differences in cloud-droplet effective radius with and without drizzle are 0.12 and 0.38 μm, respectively, for the virga and rain samples. Therefore, we conclude that the impact of drizzle on cloud property retrievals is insignificant at the ARM Azores site.

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A model sensitivity study of the impact of clouds on satellite detection and retrieval of volcanic ash

Atmospheric Measurement Techniques ◽

10.5194/amt-8-1935-2015 ◽

2015 ◽

Vol 8 (5) ◽

pp. 1935-1949 ◽

Cited By ~ 10

Author(s):

A. Kylling ◽

N. Kristiansen ◽

A. Stohl ◽

R. Buras-Schnell ◽

C. Emde ◽

...

Keyword(s):

Radiative Transfer ◽

Liquid Water ◽

Volcanic Ash ◽

Spectral Band ◽

Sensitivity Study ◽

Transfer Model ◽

Mass Loading ◽

Ice Clouds ◽

Medium Range Weather Forecast ◽

The Impact

Abstract. Volcanic ash is commonly observed by infrared detectors on board Earth-orbiting satellites. In the presence of ice and/or liquid-water clouds, the detected volcanic ash signature may be altered. In this paper the sensitivity of detection and retrieval of volcanic ash to the presence of ice and liquid-water clouds was quantified by simulating synthetic equivalents to satellite infrared images with a 3-D radiative transfer model. The sensitivity study was made for the two recent eruptions of Eyjafjallajökull (2010) and Grímsvötn (2011) using realistic water and ice clouds and volcanic ash clouds. The water and ice clouds were taken from European Centre for Medium-Range Weather Forecast (ECMWF) analysis data and the volcanic ash cloud fields from simulations by the Lagrangian particle dispersion model FLEXPART. The radiative transfer simulations were made both with and without ice and liquid-water clouds for the geometry and channels of the Spinning Enhanced Visible and Infrared Imager (SEVIRI). The synthetic SEVIRI images were used as input to standard reverse absorption ash detection and retrieval methods. Ice and liquid-water clouds were on average found to reduce the number of detected ash-affected pixels by 6–12%. However, the effect was highly variable and for individual scenes up to 40% of pixels with mass loading >0.2 g m−2 could not be detected due to the presence of water and ice clouds. For coincident pixels, i.e. pixels where ash was both present in the FLEXPART (hereafter referred to as "Flexpart") simulation and detected by the algorithm, the presence of clouds overall increased the retrieved mean mass loading for the Eyjafjallajökull (2010) eruption by about 13%, while for the Grímsvötn (2011) eruption ash-mass loadings the effect was a 4% decrease of the retrieved ash-mass loading. However, larger differences were seen between scenes (standard deviations of ±30 and ±20% for Eyjafjallajökull and Grímsvötn, respectively) and even larger ones within scenes. The impact of ice and liquid-water clouds on the detection and retrieval of volcanic ash, implies that to fully appreciate the location and amount of ash, hyperspectral and spectral band measurements by satellite instruments should be combined with ash dispersion modelling.

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The impact cross section of ErF3 centers in ZnS thin film

Journal of Luminescence ◽

10.1016/0022-2313(88)90437-1 ◽

1988 ◽

Vol 40-41 ◽

pp. 786-787

Author(s):

Baozhu Luo ◽

Jiaqi Yu ◽

Guozhu Zhong

Keyword(s):

Thin Film ◽

Cross Section ◽

The Impact

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