bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporating oxygenation levels in analytical DNA-damage models—quantifying the oxygen fixation mechanism
Authors: Van den Heuvel Frank , Vella Anna , Fiorini Francesca , Brooke Mark , Hill Mark A , Maughan Tim 
Published: June 2021

Abstract

Purpose. To develop a framework to include oxygenation effects in radiation therapy treatment planning which is valid for all modalities, energy spectra and oxygen levels. The framework is based on predicting the difference in DNA-damage resulting from ionising radiation at variable oxygenation levels. Methods. Oxygen fixation is treated as a statistical process in a simplified model of complex and simple damage. We show that a linear transformation of the microscopic oxygen fixation process allows to extend this to all energies and modalities, resulting in a relatively simple rational polynomial expression. The model is expanded such that it can be applied for polyenergetic beams. The methodology is validated using Microdosimetric Monte Carlo Damage Simulation code (MCDS). This serves as a bootstrap to determine relevant parameters in the analytical expression, as MCDS is shown to be extensively verified with published empirical data. Double-strand break induction as calculated by this methodology is compared to published proton experiments. Finally, an example is worked out where the oxygen enhancement ratio (OER) is calculated at different positions in a clinically relevant spread out Bragg peak (SOBP) dose deposition in water. This dose deposition is obtained using a general Monte Carlo code (FLUKA) to determine dose deposition and locate fluence spectra. Results. For all modalities (electrons, protons), the damage categorised as complex could be parameterised to within 0.3% of the value calculated using microdosimetric Monte Carlo. The proton beam implementation showed some variation in OERs which differed slightly depending on where the assessment was made; before the SOBP, mid-SOBP or at the distal edge. Environment oxygenation was seen to be the more important variable. Conclusions. An analytic expression calculating complex damage depending on modality, energy spectrum, and oxygenation levels was shown to be effective and can be readily incorporated in treatment planning software, to take into account the impact of variable oxygenation, forming a first step to an optimised treatment based on biological factors.
Laser-assisted propagation of a relativistic electron bunch in air
Authors: Trines R M G M , Robinson A P L , Wilkinson J R , Kirk J N , Hills D S , Deas R M , Morris S , Goffrey T , Bennett K , Arber T D 
Published: June 2021

Abstract
This paper assesses the feasibility of using kilo-joule class laser systems to pre-ionise an air column enhancing the propagation of relativistic electron beams. In a vacuum a charged beam will always diverge. In a plasma it may focus depending on the degree of beam charge and current neutralisation. Beams diverge due to scattering, but this paper highlights a parameter regime where plasma focusing in a pre-formed plasma may allow propagation of ∼10 GeV electron beams over a distance ∼10 m. Central to this theory is the degree to which the background plasma acts to charge or current neutralise the electron beam. These effects are quantified in a reduced 2D model using relativistic kinetic plasma simulations. These demonstrate that charge neutralisation is sufficiently high, and current neutralisation sufficiently low, that the proposed scheme is viable. The key problem identified in this paper is the difficulty in forming a suitable ionised channel. The primary laser energy loss mechanism for the parameters chosen is through inverse bremsstrahlung, not air ionisation, and possible ways to mitigate these losses are discussed.
eduPIC: an introductory particle based code for radio-frequency plasma simulation
Authors: Donkó Zoltán , Derzsi Aranka , Vass Máté , Horváth Benedek , Wilczek Sebastian , Hartmann Botond , Hartmann Peter 
Published: June 2021

Abstract
Particle based simulations are indispensable tools for numerical studies of charged particle swarms and low-temperature plasma sources. The main advantage of such approaches is that they do not require any assumptions regarding the shape of the particle velocity/energy distribution function (VDF/EDF), but provide these basic quantities of kinetic theory as a result of the computations. Additionally, they can provide, e.g. transport coefficients, under arbitrary time and space dependence of the electric/magnetic fields. For the self-consistent description of various plasma sources operated in the low-pressure (nonlocal, kinetic) regime, the particle-in-cell simulation approach, combined with the Monte Carlo treatment of collision processes (PIC/MCC), has become an important tool during the past decades. In particular, for radio-frequency (RF) capacitively coupled plasma (CCP) systems PIC/MCC is perhaps the primary simulation tool these days. This approach is able to describe discharges over a wide range of operating conditions, and has largely contributed to the understanding of the physics of CCPs operating in various gases and their mixtures, in chambers with simple and complicated geometries, driven by single- and multi-frequency (tailored) waveforms. PIC/MCC simulation codes have been developed and maintained by many research groups, some of these codes are available to the community as freeware resources. While this computational approach has already been present for a number of decades, the rapid evolution of the computing infrastructure makes it increasingly more popular and accessible, as simulations of simple systems can be executed now on personal computers or laptops. During the past few years we have experienced an increasing interest in lectures and courses dealing with the basics of particle simulations, including the PIC/MCC technique. In a response to this, the current paper (i) provides a tutorial on the physical basis and the algorithms of the PIC/MCC technique and (ii) presents a basic (spatially one-dimensional) electrostatic PIC/MCC simulation code, whose source is made freely available in various programming languages. We share the code in C/C++ versions, as well as in a version written in Rust, which is a rapidly emerging computational language. Our code intends to be a ‘starting tool’ for those who are interested in learning the details of the PIC/MCC technique and would like to develop the ‘skeleton’ code further, for their research purposes. Following the description of the physical basis and the algorithms used in the code, a few examples of results obtained with this code for single- and dual-frequency CCPs in argon are also given.
Optical emission from a ‘beam mode’ transparent cathode glow discharge
Authors: Hardiment T , Bowden M D 
Published: June 2021

Abstract
We investigate optical emission from a low-pressure ‘beam mode’ inertial electrostatic confinement glow discharge, created using cylindrical grid electrodes, having cathode inside a grounded, concentric anode. Spectral line distributions were measured in helium from this and a hollow cathode mode, with four lines emitted from singlet and triplet states with n = 3 and L = P and D compared against simple models for impact excitation by electrons and by ions and neutrals, suggesting much beam mode emission is caused by fast neutrals, and a significant component also caused by electrons. Beam mode emission occurs in a pattern of radial lines, that pass through aligned electrode apertures and extend across the chamber. Shadows cast by the electrode wires indicate electrically-neutral, beam-like sources of excitation, that cross the electrode assembly from bright radial lines in the opposing inter-electrode space, and calculated potential distributions show lensing surfaces around the anode grid apertures, focussing for inward-drifting ions. These indicate the emission pattern is caused by radially-convergent ion beams, and co-linear beams of fast neutrals produced in these. Emission was also observed with various alterations made to the electrode arrangement: with the anode removed, no beams were observed; with the cathode apertures rotated out of phase with those of the anode, bright radial beams between the electrodes followed the distribution of anode apertures; similar beams appeared with the grid cathode replaced by a solid version. In these experiments, progressive obstruction of pathways through the cathode caused increasing reduction in the beam pattern of emission beyond the anode radius, and in discharge perveance at similar pressure and voltage. Beam-like emission was also observed for a parallel-planar configuration, in which a cathode grid was held between two identical anode grids. The beam mode is shown to be a convergent, anode-focussed ion beam discharge, distinct to the star mode described elsewhere.
Dark matter and leptogenesis
from gravitational production
Authors: Bernal Nicolás , Sheng Fong Chee 
Published: June 2021

Abstract
Since the gravitational interaction is universal, any particle that ever existed, if kinematically accessible, has to be produced through her. We explore the possibility that dark matter is generated purely from gravitational scatterings together with heavy Majorana right-handed neutrinos that are long-lived. Their late decay could inject significant entropy into the thermal bath, diluting both the dark matter abundance and the cosmic baryon asymmetry, thereby imposing various constraints on the reheating dynamics.
Additionally to the entropy injection, long-lived right-handed neutrinos could also be responsible for generating the baryon asymmetry through leptogenesis, and hence establish some nontrivial relations between the dark matter and the right-handed properties, and the reheating dynamics.
Minimal warm inflation with complete medium response
Authors: Laine M. , Procacci S. 
Published: June 2021

Abstract
If a homogeneous field evolves within a medium, with the latter
gradually picking up a temperature, then the friction felt by the
field depends on how its evolution rate compares with medium time
scales. We suggest a framework which permits to
incorporate the contributions from all medium time scales. As an
example, we illustrate how warm axion inflation can be described by
inputting the retarded pseudoscalar
correlator of a thermal Yang-Mills plasma.
Adopting a semi-realistic model for the latter,
and starting the evolution at almost vanishing temperature,
we show how the system heats up and then enters
the “weak” or “strong” regime of warm inflation.
Previous approximate treatments are scrutinized.
Non-minimally coupled curvaton
Authors: Liu Lei-Hua , Prokopec Tomislav 
Published: June 2021

Abstract
We investigate two-field inflationary models in which scalar cosmological pertubations are generated via
a spectator field nonminimally
coupled to gravity, with the particular emphasis on
curvaton scenarios.
The principal advantage of these models is in the possibility to tune
the spectator spectral index via the nonminimal coupling.
Our models naturally yield red spectrum of the adiabatic perturbation demanded by observations.
We study how the nonminimal coupling affects the spectrum of the curvature perturbation
generated in the curvaton scenarios. In particular we find that for small, negative nonminimal couplings
the spectral index gets a contribution that is negative and linear in the nonminimal coupling.
Since in this way the curvature spectrum becomes redder, some of curvaton scenarios can
be saved, which would otherwise be ruled out.
In the power law inflation we find that a large nonminimal coupling is excluded since
it gives the principal slow-roll parameter that is of the order of unity.
Finally, we point out that nonminimal coupling can affect
the postinflationary growth of the spectator perturbation,
and in this way the effectiveness of the curvaton mechanism.
Cross section of the Coulomb excitation of

by low energy muons *
Authors: Tkalya E. V. 
Published: June 2021

Abstract
The inelastic scattering cross section for muons,

, with energies

= 9–100 eV from the

Th nuclei is calculated in the framework of the second order of the perturbation theory for quantum electrodynamics. The dominant contribution to the excitation of the low energy isomer

Th

eV) originates from the

multipole. The excitation cross section reaches the value of

cm

in the range

10 eV. This value is four to five orders of magnitude larger than the electron excitation cross section and is sufficient for the efficient excitation of

Th on the muon beam at the next generation of muon colliders.
Exotic

molecular states and

tetraquark states with JP
=0+, 1+, 2+
*
Authors: Wang Qi-Nan , Chen Wei , Chen Hua-Xing 
Published: June 2021

Abstract
We have calculated the mass spectra for the

molecular states and

tetraquark states with

. The masses of the axial-vector

,

molecular states and

,

tetraquark states are predicted to be approximately 3.98 GeV, in good agreement with the mass of

from BESIII. In both the molecular and diquark-antidiquark scenarios, our results suggest that there may exist two almost degenerate states, as the strange partners of

and

. We propose to carefully examine

in future experiments to verify this. One may also search for more hidden-charm four-quark states with strangeness in not only the open-charm

channels but also the hidden-charm channels

,

.
The MUGAST campaign at GANIL
Authors: Assié M. 
Published: June 2021

Abstract
The paper describes the MUGAST campaign at GANIL designed for direct reaction measurement. The physics cases addressed in this campaign deal with shell model evolution, nuclear astrophysics and unbound states. The set-up consist of state-of-art stripped silicon array, MLTGAST coupled with the large acceptance spectrometer, VAMOS and with the state-of-the-art gamma array AGATA. It also accommodates cryogenic targets and specific targets. The challenges of the measurements performed are described.
The Effects of Loadings during Forward Lunge on Force Output in Dominant and Non-Dominant Leg
Authors: Nadzalan Ali Md , Shafiee Mohd Syamil , Mohamad Muhamad Hasrulnizam , Tan Kevin , Rahman Ros Idayu Abdul , Mohamad Nur Ikhwan , Pratama Rivan Saghita 
Published: June 2021

Abstract
The aim of this study was to determine and compare the force output during lunge exercises with different loadings; i) high load forward lunge (70% 1RM) and ii) low load forward lunge (30% 1RM). Thirty recreationally active, untrained men were recruited and were assigned to perform forward lunge with 70% 1RM (70FL) and 30% 1RM (30FL) with both their dominant and non-dominant leg. For both dominant and non-dominant leg, all the force variables during 70FL were significantly greater compared to 30FL. Results also showed that time to peak force and stance time was significantly shorter during 30FL compared to 70FL. Besides that, all the force variables were greater in the dominant limb compared to the non-dominant limb. Time to peak force and stance time were also shorter in dominant limb compared to the non-dominant limb. As the conclusion, assymetries exist among untrained men during forward lunge exercise for both low loads and high loads.
Influence of Water Cement Ratios on the Optimum use of Steel Slag in Concrete
Authors: Anifowose M A , Adedokun S I , Adebara S A , Adeyemi A O , Amototo I O , Olahan AB , Oyeleke M O 
Published: June 2021

Abstract
In Nigeria and numerous nations of the world, steel is mainly created from purifying of metal scrap and hundreds of tonnes of steel slag are manufactured each year. This study investigated the effect of water-cement ratios (w/c) on the optimum replacement of crushed stone with Prism Nigeria Slag (PNS) in concrete production. PNS were used to substitute crushed stone by 0, 40, 50 and 60%. A mix ratio of 1:2:4 was adopted with w/c of 0.4, 0.5, 0.6 and 0.7. Concrete cubes and cylindrical concrete specimens were cast and cured in water for 7 and 28 days. The behaviour of the hardened concrete shows consistent decreased in compressive and split tensile strengths with increase in w/c. The optimum replacement at 28th days curing for compressive strength was observed at 60% PNS for all w/c. However, the optimum replacement of split tensile strength for w/c of 0.4, 0.6 and 0.7 was found to be 60% PNS while 0.5 w/c had optimum replacement of 40% PNS. The study concluded that 60% PNS with w/c of 0.4 would produce a concrete of high compressive and split tensile strengths than traditional concrete for mix ratio 1:2:4.
Smart Agro E-Marketplace Architectural Model Based on Cloud Data Platform
Authors: Sedek Khairul Anwar , Osman Mohd Nizam , Omar Mohd Adib , Wahab Mohd Helmy Abdul , Idrus Syed Zulkarnain Syed 
Published: June 2021

Abstract
Digital marketplace provides a convenient place for farmers to market farm’s products sales anywhere anytime. If this platform is fully utilized by farmers, it can improve the sustainability of farmers in agriculture industry because it can improve sales volume and fair price for farmers and consumers. However, the current AgroBazaar Online has a few enhancements that can be proposed to improve the acceptance from farmers and consumers. Therefore, there is a need to design the system that can encourage target users to use the system and make the system easy to be used by farmers who relatively have lower ICT literacy. The main requirement to develop intelligent marketing is data to provide intelligent information and services for both farmers and consumers. This project aims to explore data strategies to provide intelligent digital agricultural marketplace based on cloud data platform. This research proposes to develop cloud data platform for e-marketplace based cloud data platform approach. The proposed methodology consists of six phases: problem identification and motivation, definition of the objectives for a solution, design and development, demonstration, evaluation, and communication. This paper proposes an architectural model of agriculture marketplace cloud based on cloud data platform. The architectural model will be used for development of e-marketplace that fulfil the Malaysia’s IR 4.0 policy and National Agro-Food Policy (NAFP).
Malware Awareness Tool for Internet Safety using Gamification Techniques
Authors: Omar Nurul Suraya , Foozy Cik Feresa Mohd , Hamid Isredza Rahmi A , Hafit Hanayanti , Arbain Adila Firdaus , Shamala Palaniappan 
Published: June 2021

Abstract
Malwares are detrimental to those who are ignorant of their existence. However, the adverse effects of malwares can be easily avoided by being aware of Internet safety. In this paper, a malware awareness tool targeted for university students was developed. The Game Development Lifecycle (GDLC) model was applied in developing this tool. The tool development phase began with initiation, then pre-production, production, testing, beta testing, and ended with the release phase. Once the malware awareness tool was developed, functionality tests and awareness level tests were conducted on university students to ensure the tool is fully operative. Through the tests, it was shown that this tool was received with positive responses from its target users. As for the awareness level test, a majority of 15 students were aware of the purpose of the gamification in the malware awareness tool. In a nutshell, the malware awareness tool that was developed raised university student’s consciousness on malwares and increased their awareness level pertaining to Internet threats.
Breakdown Characteristic of N2-CO2 Gas Mixtures under AC and DC Test Voltages
Authors: Sham N M B , Zahid N Z , Kamarudin M S , Jamail N A M , Abd-Rahman R 
Published: June 2021

Abstract
This study provides fundamental knowledge on the breakdown properties of N2-CO2 gas mixture with a ratio of 20:80, 50:50, and 80:20. The gas mixtures were tested under HVAC and HVDC voltages with 1 bar (abs) pressure. The plane-plane and needle-plane electrodes were used with gap lengths between 0.5 cm to 2.5 cm. It is found that the breakdown voltage of N2-CO2 mixture increased with the increased of CO2 content. The breakdown voltage is also affected by the increment of gap distance for both electrode geometrics; plane-plane to represent the uniform field and needle-plane as the non-uniform field. The gas under uniform field configuration has a higher ability to withstand higher voltage levels compared under non-uniform field configuration. However, the non-uniform field provides a very high electric field intensity, which implies very high electric field stress. By increasing the percentage CO2 in N2-CO2 mixture, the insulation strength can reach about 64% that of pure SF6 gas at the 0.1 MPa.
A Systematic Review for Online Learning Management System
Authors: Xin Ng Syuan , Shibghatullah Abdul Samad , Subaramaniam Kasthuri A/P , Wahab Mohd Helmy Abd 
Published: June 2021

Abstract
Currently, because of the Covid-19 pandemic there a lot of demand to use online Learning Management System (LMS). The LMS available usually offer similar features and is hard for user to choose which is appropriate for them. The key criteria for analysing LMS are learning skills tools, productivity tools and communication tools. The purpose of this paper is to do systematic review on the current LMS, the problem with current LMS and the potential solutions that might help. To serve this purpose five learning management system are chosen which are Moodle, Sakai, SumTotal, Blackboard and ATutor among the other learning management systems in the market. The reasons are it consists of open source platforms such as Moodle, ATutor and Sakai and commercial platforms such as Blackboard and SumTotal. The findings from this review is quite interesting and it can be used to help users such as university/colleges, and students in selecting their LMS. It also give some ideas to LMS developer in enhancing their LMS or proposing a new features.
Unwinding Environment in the Lecture Room Using Mobile Learning (M-Learning) Adoption among the Millennial Generation
Authors: Ibrahim Marhaiza , Khairudin Norhaiza , Salleh Danilah 
Published: June 2021

Abstract
Information and Communication Technology (ICT) has provided flexibility for teachers and students to engage in academic discourse irrespective of the location. With rapid technological advancements, Mobile learning offers incredible opportunities, especially in higher education especially during this Covid-19 pandemic. The advancement of mobile and wireless communication technologies has encouraged the mobile learning method where students are able to learn via mobile devices without being limited by space and time. The millennial generation can be situated in a real-world scenario associated with the learning content in higher education. This paper discovered how mobile learning approach can enhance engagement skills and communication skills among millennial generation and employed action research methodology. In this research, mobile learning application such as kahoot! E-exercises and e-quizzes adoption of mobile learning during lecture and outside lectures activities for conversations and consultation. The positive findings showed those students’ engagement skills and communication skills increased via the mobile learning adoption. Students had active learning opportunity where effective conversations and consultation between the lecturer and students. This paper heightens lecturer awareness in identifying the learning tasks via mobile learning that are well developed. This may further be a motivating factor to adopt measures and new strategies for the improvement of students’ skills. Statistics revealed a higher engagement rate and better communication skill when courses are delivered using the mobile learning approach.