bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary study of ring artifact detection in SPECT imaging using Jaszczak phantom
Authors: Oktaviana A T , Pawiro S A , Siswatining T , Soejoko D S 
Published: June 2019

Abstract
Inspection of imaging SPECT system performance was controlled by Quality Control (QC) regularly. Tomographic imaging parameters in QC, i.e. homogeneity, contrast, and spatial resolution should be tested. These results make it reliable whether the SPECT system will be used. The modular Jaszczak phantom was used for that purpose, as it offers the investigation to all three parameters with a single measurement. Compared to the contrast and spatial resolution, an objective identification of possible ring artifact in the homogeneity is challenging. Artifact simulation of SPECT images which have been generated by disturbance of 4 × 4 cm2 copper sheet located on surface LEHR collimator have been conducted to study the detectability of ring artifact. Uniformity section of Jaszczak phantom which filled with 99mTc was used for acquisition. The confirmed ring artifact was analyzed by Edge Detection and Circle Hough Transform provided by imageJ, and students t-test statistically. From the evaluation by edge detection and circle Hough transform, the present of ring artifact only detected in artifact SPECT images using 1.00, 0.75, and 0.50 mm copper sheet thickness, while in t-test method all copper sheet thickness (including 0.25 mm) detect ring artifact in images.
Performance evaluation of line scanning method in proton therapy
Authors: Azuma Y , Tateoka K 
Published: June 2019

AbstractProton therapy system (Sumitomo Heavy Industries, Ltd.) in Sapporo Teishinkai Hospital consists of a cyclotron, a rotating gantry and a multi-purpose nozzle. This nozzle can irradiate both wobbler beam and line scanning beam. Performance of line scanning was evaluated in this study. The authors investigated for items related to the beam delivery. Dose linearity was investigated with a water phantom and a large parallel plate chamber with several dose rates. For evaluation of irradiation time precision, a solid water phantom and the large parallel plate chamber were used. Furthermore, several spot patterns were measured by Scintillator/CCD camera system for the estimation of beam position. Dose linearity is found with less than 1.8 % error with varying conditions. Regarding irradiation time, error is also confirmed with less than about 1.4 % in this measurement. Beam position accuracy and beam size constancy is also precise enough to be used in clinical use. In conclusion, it is found that results in this study are good enough for treatment.
Monte Carlo MCNP-based simulation and radiation measurement of Yttrium-90 bremsstrahlung produced from radiation shielding apparatus
Authors: Onnomdee C , Jumpee C , Channuie J , Sinkaew P , Chuamsaamarkkee K , Charoenphun P 
Published: June 2019

Abstract
Yttrium-90 (90Y) has been widely used in therapeutic nuclear medicine including in the selective internal radiation therapy with 90Y-microsphere. In the procedure 90Y source is protected within the radiation shielding apparatus made of perspex. However, bremsstrahlung radiation may be generated when 90Y interacts with matter. The aim of this study was to evaluate bremsstrahlung radiation produced from radiation shielding apparatus using a scintillation detector and Monte Carlo simulation. The 90Y source in glass vial was placed in the radiation shielding apparatus. Bremsstrahlung measurement and spectrum were performed and recorded using thallium-doped sodium iodide (NaI(Tl)) scintillation detector. Counting time and distance between the detector and apparatus were varied to obtain the optimal condition for bremsstrahlung measurement. Monte Carlo N-Particle (MCNP) 5 was used to simulate bremsstrahlung radiation with the same geometry used in the measurement. For experimental measurement results, the optimal distance and counting time were 10 cm and 120 s, respectively. Although the result of bremsstrahlung spectrum from the detector and simulation exhibited similar trend, markedly greater count rate was observed in simulations than in detector measurements. In conclusion, 90Y bremsstrahlung can be produced from radiation protection apparatus and this can be evaluated by either measurement or simulation.
Evaluation of organ doses following high dose rate (HDR) brachytherapy of breast cancer: a Geant4 Monte Carlo simulation study
Authors: Aidil M S , Hashikin N A A , Yeong C H , Guatelli S , Ng K H , Malaroda A , Rosenfeld A B , Perkins A C 
Published: June 2019

Abstract
This study aimed to evaluate the absorbed doses received by the organs at risk (OARs) following Iridium-192 (192Ir) high dose rate (HDR) brachytherapy of the left breast. The MIRD5 adult female anthropomorphic phantom, readily available in the Geant4 Monte Carlo package was used. However, the left breast was modified from 195 to 145 cm3, to represent a breast following lumpectomy. Left breast was chosen due to its higher cancer occurrence than the right breast. The HDR sources were constructed with an outer cylindrical dimension of 4.5 mm (length) × 0.9 mm (diameter). Various influencing parameters were studied, i.e. catheter arrangement (single versus dual plane), source inter-dwell distances (5 versus 10 mm), and different radionuclides, i.e. Cobalt-60 (60Co) and 192Ir, by delivering a total treatment dose of 32 Gy to the left breast. Absorbed doses to the OARs (e.g. left lung, heart, right breast, spleen, etc.) were then evaluated. A maximum left lung dose of 1.5 Gy was recorded, while doses to the other OARs were all below 1 Gy. The treatment using dual plane catheter arrangement contributed to a slightly higher dose to the OARs, despite equal dose to the breast. There was no dose difference between different inter-dwell distances used in this study. 60Co resulted in a slightly higher left lung dose than that of 192Ir, while the results were the opposite for the other OARs. HDR brachytherapy allows high dose to be delivered to the breast within a short period of time, with minimal absorbed doses to the OARs.
Picket fence test of Agility MLCs using linac log data
Authors: Sakaria Kasmayanti , Shaheera Midi Nur , Zin Hafiz M 
Published: June 2019

Abstract
The multileaf collimator (MLC) performance is critical during intensity modulated radiotherapy (IMRT) delivery. Picket fence test is typically performed by acquiring images of MLC gaps using film or electronic portal imaging device (EPID) to assess the MLC positional accuracy as part of a comprehensive weekly quality assurance (QA) programme. This study aims to investigate the accuracy of MLC position of Agility MLCs (Elekta, Stockholm, Sweden) using linac log data. The positions of MLCs were tracked during picket fence test using Elekta’s propriety optical tracking system on the linac head. The data were recorded at four cardinal gantry angles over six weeks. The fluence from the picket fence was constructed using the tracked MLC positions and compared with the fluence obtained from EPID. The fluence of the picket fence pattern constructed from the tracking data of MLC position showed that the measured range of gap size error within -0.3 mm to 0.8 mm. The average MLC positional error tracked was 0.07 mm ± 0.14 mm (mean ± 1 SD). Gap size measured from tracking data was within the range of the results obtained from EPID. Tracking the MLC position using the optical tracking system provide a more accurate test method for routine QA of the MLC performance. Over the period of investigation, it was found that the MLC performance was within the tolerance of ± 1 mm recommended by AAPM TG142.
Study of detectors response on the scatter radiation of 6 MV flattening filter free beams
Authors: Pratiwi R D T , Ryangga D , Pawiro S A 
Published: June 2019

Abstract
Small field dosimetry which related to the use of Flattening Filter Free (FFF) beams is a great challenge because of the perturbation effects caused by the size of the detector’s active volume or detector’s materials. This phenomenon encourages researchers to do a further study about detector response. In this study, scatter and primary radiation from 6 MV FFF photon beams were studied to evaluate the detector response in small fields for a better understanding of the contribution of every phenomenon. Ion chamber and Gafchromic films were used in three measurement configurations representing open field measurement and approximations of both primary and scatter part of the beam, described as follows: (i) detectors positioned under steel block, exposing the detectors only to scatter part of radiation field, (ii) detectors positioned inside mini phantom, approximating the detector response to primary radiation with minimum scatter, (iii) detectors positioned in the standard open field, which was the superposition of the primary and scatter radiation. The results show that detector responses were heavily depended on its design (i.e. active volume) especially in small beams. The detector response in the open field could be reproduced from the blocked and primary beam set-up with a discrepancy ranging from 1.0% to 36%. Moreover, the volume averaging and other phenomenon affecting the detector response could be observed in the blocked beam.
Biodegradable Samarium-153–labelled microspheres for hepatic radioembolization: preparation, characterization and radiolabelling evaluation after neutron activation
Authors: How Wong Yin , Yee Tan Hun , Kasbollah Azahari , Johan Jeet Abdullah Basri , Nazri Md Shah Mohammad , Hong Yeong Chai 
Published: June 2019

Abstract
A biocompatible and biodegradable radioactive samarium-153 (153Sm)-labelled Poly-(L-lactic acid) (PLLA) microspheres was developed for hepatic radioembolization. Samarium acetylacetonate was encapsulated in PLLA microspheres using oil-in-water solvent evaporation method. Physicochemical characterization of the microspheres were analysed using Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray spectroscopy and particle size analyser. The prepared microspheres were irradiated in a nuclear reactor with a neutron flux of 1.49 × 1012 n.cm-2.s-1, converting 152Sm to 153Sm (Emax = 807.6 keV, half-life = 46.3 h). Gamma spectroscopy was carried out to determine the presence of radionuclide impurities while the in-vitro radiolabelling efficiency was performed to analyse the retention of 153Sm on the microspheres. The Sm-labelled PLLA microspheres was found spherical with the diameters within 20-60 μm, as indicated by the scanning electron microscopy and particle size distribution results. Gamma spectrometry suggested that no long half-life radioimpurities present after neutron activation. The 153Sm-labelled PLLA microspheres has achieved a nominal activity of 5.9 GBq.g-1 after 6 h neutron activation. The formulation showed more than 97% radiolabelling efficiency in saline and human blood plasma over 550 h. The 153Sm-labelled PLLA microspheres are potentially useful for hepatic radioembolization due to their biodegradability, favourable radiation characteristics and excellent radiolabelling efficiency. The preparation of the formulation does not involve ionizing radiation and hence reduces the costs of production.
Introducing stereotactic radiotherapy safely: credentialing centres and staff
Authors: Perkins A , Aland T , Dally M , Jhala E , Bailey N , Shannon D , Anderson L 
Published: June 2019

Abstract
Stereotactic radiotherapy treatments use high doses of radiation delivered in relatively few fractions compared with conventional radiotherapy. Specialist planning, immobilization and image guidance techniques are needed to achieve accurate treatment. Because doses are high and fractions few, the consequences of treatment errors are more severe than for conventional therapy. A credentialing program for staff and equipment is one strategy that can be used to reduce risk. The Icon Group runs a network of 20 radiotherapy centres in Australia. There has been a rapid growth of stereotactic treatments at Icon. In order to reduce the risks of introducing stereotactic therapy, an in-house credentialing and endorsement program was developed. A multi-disciplinary working group comprising medical physicists, radiation oncologists and radiation therapists was established to develop endorsement policies and procedures. Elements considered included the purchase, commissioning and quality assurance of equipment, the establishment and documentation of safe work practices and staff competency assessment. The endorsement program is in the process of being implemented across the Icon network.
Remobilization and fate of sulphur in mustard
Authors: Borpatragohain Priyakshee , Rose Terry J , Liu Lei , Barkla Bronwyn J , Raymond Carolyn A , King Graham J 
Published: June 2019

Abstract

Background and Aims
Sulphur (S) is an essential macronutrient involved in numerous metabolic pathways required for plant growth. Crops of the plant family Brassicaceae require more S compared with other crops for optimum growth and yield, with most S ultimately sequestered in the mature seeds as the storage proteins cruciferin and napin, along with the unique S-rich secondary metabolite glucosinolate (GSL). It is well established that S assimilation primarily takes place in the shoots rather than roots, and that sulphate is the major form in which S is transported and stored in plants. We carried out a developmental S audit to establish the net fluxes of S in two lines of Brassica juncea mustard where seed GSL content differed but resulted in no yield penalty.

Methods
We quantified S pools (sulphate, GSL and total S) in different organs at multiple growth stages until maturity, which also allowed us to test the hypothesis that leaf S, accumulated as a primary S sink, becomes remobilized as a secondary source to meet the requirements of GSL as the dominant seed S sink.

Key Results
Maximum plant sulphate accumulation had occurred by floral initiation in both lines, at which time most of the sulphate was found in the leaves, confirming its role as the primary S sink. Up to 52 % of total sulphate accumulated by the low-GSL plants was lost through senesced leaves. In contrast, S from senescing leaves of the high-GSL line was remobilized to other tissues, with GSL accumulating in the seed from commencement of silique filling until maturity.

Conclusion
We have established that leaf S compounds that accumulated as primary S sinks at early developmental stages in condiment type B. juncea become remobilized as a secondary S source to meet the demand for GSL as the dominant seed S sink at maturity.
X—Two Shoes and a Fountain: Ecstasis, Mimesis and Engrossment in Heidegger’s The Origin of the Work of Art
Authors: Mulhall Stephen 
Published: June 2019

AbstractIn this essay, I argue for three interpretative claims about the philosophical strategies and examples employed in the first of Heidegger’s three lectures on ‘The Origin of the Work of Art’. I argue that his initial response to a Van Gogh painting is intended to dramatize a confusion rather than to articulate an insight; that his invocation of a poem by C. F. Meyer serves a number of functions overlooked by other commentators; and that Heidegger’s overall approach is best understood in terms of Michael Fried’s conception of modernism in painting.
Chicdiff: a computational pipeline for detecting differential chromosomal interactions in Capture Hi-C data
Authors: Cairns Jonathan , Orchard William R , Malysheva Valeriya , Spivakov Mikhail 
Published: June 2019

Abstract

Summary
Capture Hi-C is a powerful approach for detecting chromosomal interactions involving, at least on one end, DNA regions of interest, such as gene promoters. We present Chicdiff, an R package for robust detection of differential interactions in Capture Hi-C data. Chicdiff enhances a state-of-the-art differential testing approach for count data with bespoke normalization and multiple testing procedures that account for specific statistical properties of Capture Hi-C. We validate Chicdiff on published Promoter Capture Hi-C data in human Monocytes and CD4+ T cells, identifying multitudes of cell type-specific interactions, and confirming the overall positive association between promoter interactions and gene expression.

Availability and implementation
Chicdiff is implemented as an R package that is publicly available at https://github.com/RegulatoryGenomicsGroup/chicdiff.

Supplementary information
Supplementary data are available at Bioinformatics online.
Etiology of Pediatric Bacterial Meningitis Pre- and Post-PCV13 Introduction Among Children Under 5 Years Old in Lomé, Togo
Authors: Tsolenyanu Enyonam , Bancroft Rowan E , Sesay Abdul K , Senghore Madikay , Fiawoo Mawouto , Akolly Djatougbe , Godonou Mawussi A , Tsogbale Novissi , Tigossou Segla D , Tientcheu Leopold , Dagnra Anoumou , Atakouma Yawo , Sylvanus Ndow Peter , Worwui Archibald , Landoh Dadja E , Mwenda Jason M , Biey Joseph N , Ntsama Bernard , Kwambana-Adams Brenda A , Antonio Martin 
Published: June 2019

Abstract

Background
Pediatric bacterial meningitis (PBM) causes severe morbidity and mortality within Togo. Thus, as a member of the World Health Organization coordinated Invasive Bacterial Vaccine Preventable Diseases network, Togo conducts surveillance targeting Streptococcus pneumoniae (pneumococcus), Neisseria meningitidis (meningococcus), and Haemophilus influenzae, at a sentinel hospital within the capital city, Lomé, in the southernmost Maritime region.

Methods
Cerebrospinal fluid was collected from children <5 years with suspected PBM admitted to the Sylvanus Olympio Teaching Hospital. Phenotypic detection of pneumococcus, meningococcus, and H. influenzae was confirmed through microbiological techniques. Samples were shipped to the Regional Reference Laboratory to corroborate results by species-specific polymerase chain reaction.

Results
Overall, 3644 suspected PBM cases were reported, and 98 cases (2.7%: 98/3644) were confirmed bacterial meningitis. Pneumococcus was responsible for most infections (67.3%: 66/98), followed by H. influenzae (23.5%: 23/98) and meningococcus (9.2%: 9/98). The number of pneumococcal meningitis cases decreased by 88.1% (52/59) postvaccine introduction with 59 cases from July 2010 to June 2014 and 7 cases from July 2014 to June 2016. However, 5 cases caused by nonvaccine serotypes were observed. Fewer PBM cases caused by vaccine serotypes were observed in infants <1 year compared to children 2–5 years.

Conclusions
Routine surveillance showed that PCV13 vaccination is effective in preventing pneumococcal meningitis among children <5 years of age in the Maritime region. This complements the MenAfriVac vaccination against meningococcal serogroup A to prevent meningitis outbreaks in the northern region of Togo. Continued surveillance is vital for estimating the prevalence of PBM, determining vaccine impact, and anticipating epidemics in Togo.
Impact of 13-Valent Pneumococcal Conjugate Vaccine on Colonization and Invasive Disease in Cambodian Children
Authors: Turner Paul , Leab Phana , Ly Sokeng , Sao Sena , Miliya Thyl , Heffelfinger James D , Batmunkh Nyambat , Lessa Fernanda C , Walldorf Jenny A , Hyde Terri B , Ork Vichit , Hossain Md Shafiqul , Gould Katherine A , Hinds Jason , Cooper Ben S , Ngoun Chanpheaktra , Turner Claudia , Day Nicholas P J 
Published: June 2019

Abstract

Background
Cambodia introduced the 13-valent pneumococcal conjugate vaccine (PCV13) in January 2015 using a 3 + 0 dosing schedule and no catch-up campaign. We investigated the effects of this introduction on pneumococcal colonization and invasive disease in children aged &lt;5 years.

Methods
There were 6 colonization surveys done between January 2014 and January 2018 in children attending the outpatient department of a nongovernmental pediatric hospital in Siem Reap. Nasopharyngeal swabs were analyzed by phenotypic and genotypic methods to detect pneumococcal serotypes and antimicrobial resistance. Invasive pneumococcal disease (IPD) data for January 2012–December 2018 were retrieved from hospital databases. Pre-PCV IPD data and pre-/post-PCV colonization data were modelled to estimate vaccine effectiveness (VE).

Results
Comparing 2014 with 2016–2018, and using adjusted prevalence ratios, VE estimates for colonization were 16.6% (95% confidence interval [CI] 10.6–21.8) for all pneumococci and 39.2% (95% CI 26.7–46.1) for vaccine serotype (VT) pneumococci. There was a 26.0% (95% CI 17.7–33.0) decrease in multidrug-resistant pneumococcal colonization. The IPD incidence was estimated to have declined by 26.4% (95% CI 14.4–35.8) by 2018, with a decrease of 36.3% (95% CI 23.8–46.9) for VT IPD and an increase of 101.4% (95% CI 62.0–145.4) for non-VT IPD.

Conclusions
Following PCV13 introduction into the Cambodian immunization schedule, there have been declines in VT pneumococcal colonization and disease in children aged &lt;5 years. Modelling of dominant serotype colonization data produced plausible VE estimates.
Validation of the Strengths and Difficulties Self-Report in Norwegian Sign Language
Authors: Aanondsen Chris Margaret , Jozefiak Thomas , Heiling Kerstin , Rimehaug Tormod 
Published: June 2019

Abstract
The majority of studies on mental health in deaf and hard-of-hearing (DHH) children report a higher level of mental health problems. Inconsistencies in reports of prevalence of mental health problems have been found to be related to a number of factors such as language skills, cognitive ability, heterogeneous samples as well as validity problems caused by using written measures designed for typically hearing children. This study evaluates the psychometric properties of the self-report version of the Strengths and Difficulties Questionnaire (SDQ) in Norwegian Sign Language (NSL; SDQ-NSL) and in written Norwegian (SDQ-NOR). Forty-nine DHH children completed the SDQ-NSL as well as the SDQ-NOR in randomized order and their parents completed the parent version of the SDQ-NOR and a questionnaire on hearing and language-related information. Internal consistency was examined using Dillon–Goldstein’s rho, test–retest reliability using intraclass correlations, construct validity by confirmatory factor analysis (CFA), and partial least squares structural equation modeling. Internal consistency and test–retest reliability were established as acceptable to good. CFA resulted in a best fit for the proposed five-factor model for both versions, although not all fit indices reached acceptable levels. The reliability and validity of the SDQ-NSL seem promising even though the validation was based on a small sample size.