bluuebunny/crossref_metadata_2025_split huggingface dataset:
Knowledge of Pregnant Adolescents about Human Papillomavirus
Authors: Tanaka Erika Zambrano , Kamizaki Sílvia Souza , Quintana Silvana Maria , Pacagnella Rodolfo de Carvalho , Surita Fernanda Garanhani 
Published: June 2019

Objective To evaluate the level of information possessed by pregnant adolescents regarding the human papillomavirus (HPV).
Methods Descriptive study developed in the adolescent prenatal outpatient clinic of a tertiary hospital from the state of São Paulo, Brazil. Data were collected between June and December 2017 following approval from the ethics and research committee (CAAE: 1.887.892/2017). Pregnant adolescents, ≤18 years old, who attended the abovementioned outpatient section, composed the sample. Those diagnosed with a psychiatric disorder and those with hearing or cognitive disabilities were excluded. After acceptance to participate in the present study, the pregnant adolescents signed an Informed Consent Form. Regarding the statistical analysis, the chi-squared test and the Fisher exact test were used.
Results Regarding the knowledge about HPV, 123 (80.92%) of the participants had already heard about the subject; for 77 (50.66%), their schools had been the source of the information; 101 (66.45%) did not know how they could be infected by the virus. Age variation did not influence their knowledge on how to prevent themselves from HPV (p = 0.2562). The variable vaccine is associated with HPV prevention (p < 0.0001).
Conclusion The pregnant adolescents composing the sample have shown to have knowledge about HPV. However, they do not prevent themselves from it appropriately, given that little more than half of the sample was vaccinated, had not reported an understanding that the use of preservatives and vaccination are effective means of prevention, and did not correlate HPV with uterine cervical cancer.
Into the ordinary: non-elite actors and the mobility of harm reduction policies
Authors: Baker Tom , McCann Eugene , Temenos Cristina 
Published: June 2019

Abstract
Research on policy transfer and policy mobility has focused much attention on relatively elite actors, such as politicians, international organisations, think tanks, philanthropic donors, and consultancy firms. In contrast, this article uses the case of ‘harm reduction’ drug policy, an area of practice and research that is committed to valuing ‘non-elite’ actors, to show how they are frequently involved in mobilizing policy knowledge. Focusing on the role of service providers, activists and service users in the mobilization of harm reduction models, the paper discusses four key practices associated with these non-elite actors: cooperation, convergence, disobedience and display. The article argues that the deep involvement of relatively non-elite actors in mobilizing harm reduction policies means that multi-disciplinary scholarship would be enriched by going ‘into the ordinary’ in a wide range of policy contexts.
Are wicked problems really so wicked? Perceptions of policy problems
Authors: Peters B Guy , Tarpey Matthew 
Published: June 2019

AbstractThe concept of wicked problems has become widely used in policy analysis. The popularity of the concept has led to its overuse, and has produced significant conceptual stretching. This paper investigates the extent to which this stretching has led to the application of the concept to issues which are not ‘wicked’ in any meaningful sense. Based on a survey of policy experts, we find that few, if any, policy problems are perceived to have all the attributes of wicked problems. Although the concept does not appear useful in categorizing problems in a strict manner, the presence or absence of certain attributes can still be used in understanding the problems and in designing solutions for them.
Iron self diffusion in liquid pure iron and iron-carbon alloys
Authors: Meyer A , Hennig L , Kargl F , Unruh T 
Published: June 2019

Abstract
With incoherent quasielastic neutron scattering self-diffusion coefficients

in pure iron, and iron-carbon alloys containing 8.7 at% and 16.9 at% carbon have been measured. At the melting point

in liquid iron is

m2 s−1. For the close-to-eutectic Fe83.1C16.9 composition

m2 s−1 at T

K. Contradicting conclusions drawn from literature values of tracer diffusion experiments the addition of carbon has only a minor effect on the iron mobility: at a given temperature the self-diffusion coefficient in Fe83.1C16.9 is only 10% larger than in liquid iron, although mixing has a drastic effect on liquidus temperature and phase behavior.
Microplasticity and yielding in crystals with heterogeneous dislocation distribution
Authors: Zhang Xu , Xiong Jian , Fan Haidong , Zaiser Michael 
Published: June 2019

Abstract
In this study, we use discrete dislocation dynamics simulation to investigate the effect of heterogeneous dislocation density on the transition between quasi-elastic deformation and plastic flow in face-centered cubic single crystals. By analyzing the stress–strain curves of samples with an initial, axial dislocation density gradient, we arrive at the following conclusions: (i) in the regime of quasi-elastic deformation before the onset of plastic flow, the effective elastic modulus of the simulated samples falls significantly below the value for a dislocation-free crystal. This modulus reduction increases with decreasing dislocation density gradient: crystals with homogeneous dislocation distribution are thus weakest in the quasi-elastic regime; (ii) the transition towards plastic flow occurs first in regions of reduced dislocation density. Therefore, the overall yield stress decreases with increasing dislocation density gradient; (iii) crystals with dislocation density gradient exhibit a more pronounced hardening stage during which stress is re-distributed onto stronger regions with higher dislocation density until the sample flows at a constant flow stress that is approximately independent of dislocation density gradient. We interpret these findings in terms of a continuum dislocation dynamics inspired model of dislocation density evolution that accounts for geometrically reversible (‘inversive’) dislocation motions. The transition between quasi-elastic and plastic deformation is interpreted as a transition from inversive to non-inversive dislocation motion, and the initial differences in elastic modulus are related to a density dependent polarizability of the dislocation system. The subsequent plastic flow behavior is analyzed in terms of a modified version of Mughrabi’s composite model.
A finite element method for the determination of the relative response of ionization chambers in MR-linacs: simulation and experimental validation up to 1.5 T
Authors: Pojtinger Stefan , Kapsch Ralf-Peter , Dohm Oliver Steffen , Thorwarth Daniela 
Published: June 2019

Abstract
In magnetic resonance (MR) guided radiotherapy, the magnetic field-dependent change in the dose response of ionization chambers is typically included by means of a correction factor

. This factor can be determined experimentally or calculated by means of Monte Carlo (MC) simulations. To date, a small number of experimental values for

at magnetic flux densities above 1.2 T have been available to benchmark these simulations. Furthermore, MC simulations of the dose response of ionization chambers in magnetic fields (where such simulations are based on manufacturer blueprints) have been shown to converge with results that deviate considerably from experimental values for orientations where the magnetic field is perpendicular to the axis of the ionization chamber and the influence of the magnetic field is largest.
In this work,

was simulated for a PTW 30013 Farmer ionization chamber using an approach based on finite element simulations. First, the electrical field inside the ionization chamber was simulated using finite element methods. The collecting volume of the ionization was not defined in terms of the physical dimensions of the detector but in terms of the simulated electrical field lines inside the chamber. Then, an MC simulation of the dose response of a Farmer type chamber (PTW 30013) was performed using EGSnrc with a dedicated package to consider the effect of the magnetic field. In the second part,

was determined experimentally for two different PTW 30013 ionization chambers for a range of magnetic flux densities between B  =  0 and 1.5 T, covering the range of commercially available MR-linacs.
In the perpendicular orientation, the maximum difference between the simulated values for

and the experimental values for

was 0.31(30)% and the minimum difference was 0.02(24)%. For the PTW 30013 ionization chambers, the experimental values for

were 0.9679(1) and 0.9681(1) for a magnetic flux density of 1.5 T. The value resulting from the simulation was 0.967(3).
The comparison of the correction factors simulated using this new approach with the experimental values determined in this study shows excellent agreement for all magnetic flux densities up to 1.5 T. Integrating the explicit simulation of the collection volume inside the ionization chambers into the MC simulation model significantly improves simulations of the chamber response in magnetic fields. The results presented suggest that intra-type variations for

may be neglectable for ionization chambers of the PTW 30013 type.
Can an injection model replenish filaments in a weak magnetic environment?
Authors: Zou Peng , Jiang Chao-Wei , Wei Feng-Si , Cao Wen-Da 
Published: June 2019

Abstract
We observed an Hα surge that occurred in NOAA Active Region 12401 on 2015 August 17, and we discuss its trigger mechanism, and kinematic and thermal properties. It is suggested that this surge was caused by a chromospheric reconnection which ejected cool and dense material with transverse velocity of about 21–28 km s−1 and initial Doppler velocity of 12 km s−1. This surge is similar to the injection of newly formed filament materials from their footpoints, except that the surge here occurred in a relatively weak magnetic environment of ∼100 G. Thus, we discuss the possibility of filament material replenishment via the erupting mass in such a weak magnetic field, which is often associated with quiescent filaments. It is found that the local plasma can be heated up to about 1.3 times the original temperature, which results in an acceleration of about –0.017 km s−2. It can lift the dense material up to 10 Mm and higher with an inclination angle smaller than 50°, namely the typical height of active region filaments, but it can hardly inject the material up to those filaments higher than 25 Mm, like some quiescent filaments. Thus, we think that the injection model does not work well in describing the formation of quiescent filaments.
Polymer-encapsulated molecular doped epigraphene for quantum resistance metrology
Authors: He Hans , Lara-Avila Samuel , Kim Kyung Ho , Fletcher Nick , Rozhko Sergiy , Bergsten Tobias , Eklund Gunnar , Cedergren Karin , Yakimova Rositsa , Park Yung Woo , Tzalenchuk Alexander , Kubatkin Sergey 
Published: June 2019

Abstract
One of the aspirations of quantum metrology is to deliver primary standards directly to end-users thereby significantly shortening the traceability chains and enabling more accurate products. Epitaxial graphene grown on silicon carbide (epigraphene) is known to be a viable candidate for a primary realisation of a quantum Hall resistance standard, surpassing conventional semiconductor two-dimensional electron gases, such as those based on GaAs, in terms of performance at higher temperatures and lower magnetic fields. The bottleneck in the realisation of a turn-key quantum resistance standard requiring minimum user intervention has so far been the need to fine-tune the carrier density in this material to fit the constraints imposed by a simple cryo-magnetic system. Previously demonstrated methods, such as via photo-chemistry or corona discharge, require application prior to every cool-down as well as specialist knowledge and equipment. To this end we perform metrological evaluation of epigraphene with carrier density tuned by a recently reported permanent molecular doping technique. Measurements at two National Metrology Institutes confirm accurate resistance quantisation below 5 nΩ Ω−1. Furthermore, samples show no significant drift in carrier concentration and performance on multiple thermal cycles over three years. This development paves the way for dissemination of primary resistance standards based on epigraphene.
Rotation in galaxy clusters from MUSIC simulations with the kinetic Sunyaev–Zel’dovich effect
Authors: Baldi A S , De Petris M , Sembolini F , Yepes G , Cui W , Lamagna L 
Published: June 2019

AbstractThe Sunyaev-Zel’dovich effect in galaxy clusters is a unique probe for studying astrophysics and cosmology. We propose in this work its application for the detection of possible coherent rotational motions in the hot intra-cluster medium. We select a sample of massive, relaxed and rotating galaxy clusters from Marenostrum-mUltidark SImulations of galaxy Clusters (MUSIC), and we produce mock maps of the temperature distortion produced by the kinetic Sunyaev–Zel’dovich effect by exploring six different lines of sight, in the best observational condition. These maps are compared with the expected signal computed from a suitable theoretical model in two cases: (i) focusing only on the contribution from the rotation, and (ii) accounting also for the cluster bulk motion. We find that the parameters of the model assumed for the radial profile of the rotational velocity, averaged over the considered lines of sight, are in agreement within two standard deviations at most with independent estimates from the simulation data, without being significantly affected by the presence of the cluster bulk term. The amplitude of the rotational signal is, on average, of the order of 23 per cent of the total signal accounting also for the cluster bulk motion, and its values are consistent with the literature. The projected bulk velocity of the cluster is also recovered at the different lines of sight, with values in agreement with the simulation data.
Radiochromic films in Radiation Hardness Space Application
Authors: Casolaro P , Campajola L , De Luca D 
Published: June 2019

Abstract
The characteristics of radiochromic films such as the direct visualization of radiation field, ease of use and data analysis are suited for the dosimetry monitoring in tests of radiation hardness space applications. In particular, in this work, in order to study the dependence of radiation type, energy and dose rate, as well as the dynamic range of EBT3 Gafchromic films, a set of films was exposed to radiation sources used in total ionizing dose (60Co gamma- and 90Sr/90Y beta-rays). The results have been found to be particularly suited for the employment of this kind of films in radiation hardness assurance tests.
Two-dimensional effects in Fowler-Nordheim field emission from transition metal dichalcogenides
Authors: Urban F , Passacantando M , Giubileo F , Iemmo L , Luongo G , Grillo A , Di Bartolomeo A 
Published: June 2019

Abstract
We report field emission from bilayer MoS
2 and monolayer WSe
2 synthesized by CVD on SiO
2/Si substrate. We show that the emitted current follows a Fowler-Nordheim model modified to account for the two-dimensional confinement of charge carriers. We derive the figures of merit of field emission and demonstrate that few-layer transition-metal dichalcogenides are suitable for field emission applications.
Thermal Behaviour of Zr65Cu17.5Ni10Al7.5 Glassy Alloy
Authors: Aji Daisman P.B. , Triyono  , Mujalis Yusep 
Published: June 2019

Abstract
Estimating entropy of glass cannot be performed using the time-dependent and irreversible part of the heat capacity (Cp
) which is measured in the glass-formation range. The difference of the estimate and the real change in entropy can be determined by calculating the change in the CpdT and CpdlnT integrals before and after isothermal annealing by using DSC. In this paper, we report this estimation difference for Zr65Cu17.5Ni10Al7.5 glassy alloy. The minimized annealing results in the CpdlnT integrals for the cooling and the heating paths approach the same value. We affirm that entropy is an ensemble-averaged value since the Clausius limits show that the estimation of the residual entropy is not affected significantly by irreversibility and its value can be estimated from the Cp
data.
Removal and Kinetics Adsorption Fe (II) Ions in Ground Water using Sugarcane Bagasse of Various Treatments Adsorbent with Column Method
Authors: Halim ZU , Cut AR , Said AB 
Published: June 2019

Abstract
After the water adsorption process, the content of Fe (II) ion meets drinking water standard below 0.3 ppm. Based on the kinetic indicator of the absorption coefficient of correlation (R2), the adsorption rate constant k1 and k2 and the calculated qe and qe extrapolation data can be concluded the content of Fe (II) ions in groundwater above 0.3 ppm can cause serious problems for human health. A relatively effective, efficient, safe, environmentally friendly separation method is the adsorption method. The mechanism of adsorption of Fe (II) ions in the well water can be studied using pseudo-first-order and pseudo-second-order. Based on the experimental design, fixed variables consisted of 50 g of adsorbent, 20 mesh particle size, 10-liter adsorbate volume, 4liters/min flow rate and operating temperature at room temperature. The independent variable consists of contact time and the type of treatment of the adsorbent. Variation of contact time 0; 30; 60; 90; 120; 150; 180; 210; 240 minutes and type of adsorbent treatment: without treatment, physical treatment and chemical treatment (H2SO4 0.5N and NaOH 0.5N). The results showed that the adsorption of Fe (II) ion was influenced by contact time and type of adsorbent treatment. that the kinetic adsorption of Fe (II) ion is showing the second order pseudo adsorption kinetics with R2 value for the adsorbent without treatment: 9636, physical treatment: 0.9028, treatment with H2SO4 0.5N: 0.9578, treatment with NaOH 0.5N: 0.9967. Results of qe of adsorption kinetics for non-treated adsorbents: 0.224 mg/g, physical treatment: 0.257 mg/g, treatment with H2SO4 0.5N: 0.258 mg/g and NaOH treatment 0.5N: 0.218 mg/g.
The Effect of Chemical Composition on Grain Size and Formability of the Free-Lead Cu-30Zn Alloy: A Short Review
Authors: Ibrahim Akhyar , Rizal Samsul , Ali Nurdin , Huzni Syifaul 
Published: June 2019

Abstract
The increasing demand for free-lead Cu30Zn alloy for all industrial applications has prompted to develop the grain size and formability. One of the major challenges facing the researcher and industry is decreasing the formability and machinability which requires continuous improvements in design and fabrication techniques. The current trend for free-lead Cu30Zn alloy in these categories is reviewed. Results show that developments in free-lead Cu30Zn alloy are affected by a lot of factors such as chemical composition, microstructure, grain size, strain and hardness. A highly developed system with characteristics of compromised decision making became more favorable and initiated an interesting intervention since the casting, cold working, and heat treatment is controlled.
Effect of Metallization Condition on Mechanical Strength of Multi Crystalline Silicon Solar Cell
Authors: Yunus Azwar , Saifuddin  
Published: June 2019

Abstract
During each processing step of multicrystalline (mc) silicon solar cells production, it requires a good mechanical stability to avoid cell breakage. Therefore, wafers and cells with a good mechanical stability are absolutely important. The cracking of silicon wafer solar cells is one of the major failures of solar module. Hence, it is important to evaluate the mechanical strength of solar cells and influenced factor. The present work focuses on determining the effect of metallization conditions on mechanical strength of multi crystalline silicon solar cells. A 4-point bending method was used to measure the fracture strength and data is statistically evaluated by a Weibull analysis for interpretation of the flaws within the specimen. It was observed that drying temperature at 250 °C provides better results than 350 °C. It was found that the contact formation between metal layer and silicon wafer (i.e. eutectic layer) has a significant effect on mechanical properties of mc-silicon solar cells. Moreover, the mesh sizes of screen printing produce different thickness of metal layer without altering the strength of silicon wafer. It was discovered that the metallization process was responsible to alter the mechanical strength of mc-silicon solar cell. It is also observed that the crack can initiate from the edge and surface defects and propagate along the preferred crystallographic plane. It was found that the edge defects look like more dominant as crack initiation.
Optimization of Angle Adjustment Between Two Cutters’ Blades of Dry Areca Nut Peeling and Controlling Machine
Authors: Darmein  , Usman R. , Rusli  
Published: June 2019

Abstract
The peeling-machine of dry areca nut is currently not working optimally. The nuts remained unpeeled properly since the machine is not equipped with an automatic power breaker as the peeler process has been completed or the machine life time is continuously. Undoubtedly, this is less efficient and wasteful of energy. From this point of views, it is necessary to conduct advanced research on appropriate technology to modify the peeling-machine so that it can peel dry areca nuts to the maximum for all available sizes. The research method includes the assembly of areca peeling-machine with a modification of the angle between the two cutters’ blades, the dimensions of the main cutter shape 191 mm in diameter cylinders that can be arranged into 12 cutters function as a peeler and a second cutter 163 mm in diameter with 20 cutters function towards the skin through the exhaust channel, rotation in the equal direction of 800 rpm. The peeler process is set to the angle between the two cutters’ blades and directed to the further process so that the dried areca nut that has been cut can be separated between the seeds and the skin. That is the expected result of the peeling-machine that can peel the dry areca nuts for all sizes optimally.
Feasibility of Utilize Sidoarjo Mud as Replacement Material in Fly Ash Based Geopolymer Binder
Authors: Syukri  , Fauzi Amir , Majuar Edi , Mulizar  
Published: June 2019

Abstract
Sidoarjo mudflow (SM) is an alternative source material in the construction which was generated from natural disasters of volcano mudflow in Porong, Sidoarjo, East Java, Indonesia. The source material of SM has high Si and Al content that contributed to geopolymer binder. Yet, it was categorized as low Ca content that caused prolong setting time in the geopolymer binder. This study aimed to increase the Ca content by incorporating the source material of SM in FA based geopolymer so that was able to provide short setting time in the field. The results showed that the particle properties of SM material were agglomerate irregular shape and rough surface. The increase of SM replacement caused the reduction of workability in fresh geopolymer mortar. Replacement of 40% SM in FA based geopolymer provided the short setting time less than 2.5 hours. The replacement of 15% SM in FA based geopolymer enhanced the compressive strength of 7.6%. However, the highest compressive strength of 9.4% was obtained by the replacement of 10% SM.