bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accessible magnetic resonance imaging: A review
Authors: Geethanath Sairam , Vaughan John Thomas 
Published: January 2019

The role of MRI in diagnostics, prognostics, and discoveries in basic sciences has been well established. However, access to this life‐saving technology is largely restricted to countries in upper‐middle to high‐income groups. In this article, we collate recent global MR scanner density data and group them into six geographical regions based on the WHO classification. We then analyze these data with respect to demographic factors such as population size, life expectancy, the percentage of internet users, and World Bank income grouping. We map these demographic factors to five dimensions or characteristics of accessible MRI, adapting definitions from the healthcare literature. With this background, the study then reviews recent demonstrations of accessible MRI categorized based on main magnetic field strength. We describe demonstrated examples for each of these categories, ranging from ultralow‐field to ultrahigh‐field MRI. Lastly, we review MR methods and associated developments impacting accessible MRI such as increasing/augmenting MR awareness and local expertise, incorporating hardware‐cognizant methods, rapid quantitative imaging, and leveraging innovations from adjacent fields.Level of Evidence: 5Technical Efficacy Stage: 6J. Magn. Reson. Imaging 2019.
Accuracy of blood flow assessment in cerebral arteries with 4D flow MRI: Evaluation with three segmentation methods
Authors: Dunås Tora , Holmgren Madelene , Wåhlin Anders , Malm Jan , Eklund Anders 
Published: January 2019

BackgroundAccelerated 4D flow MRI allows for high‐resolution velocity measurements with whole‐brain coverage. Such scans are increasingly used to calculate flow rates of individual arteries in the vascular tree, but detailed information about the accuracy and precision in relation to different postprocessing options is lacking.PurposeTo evaluate and optimize three proposed segmentation methods and determine the accuracy of in vivo 4D flow MRI blood flow rate assessments in major cerebral arteries, with high‐resolution 2D PCMRI as a reference.Study TypeProspective.SubjectsThirty‐five subjects (20 women, 79 ± 5 years, range 70–91 years).Field Strength/Sequence4D flow MRI with PC‐VIPR and 2D PCMRI acquired with a 3 T scanner.AssessmentWe compared blood flow rates measured with 4D flow MRI, to the reference, in nine main cerebral arteries. Lumen segmentation in the 4D flow MRI was performed with k‐means clustering using four different input datasets, and with two types of thresholding methods. The threshold was defined as a percentage of the maximum intensity value in the complex difference image. Local and global thresholding approaches were used, with evaluated thresholds from 6–26%.Statistical TestsPaired t‐test, F‐test, linear correlation (P < 0.05 was considered significant) along with intraclass correlation (ICC).ResultsWith the thresholding methods, the lowest average flow difference was obtained for 20% local (0.02 ± 15.0 ml/min, ICC = 0.97, n = 310) or 10% global (0.08 ± 17.3 ml/min, ICC = 0.97, n = 310) thresholding with a significant lower standard deviation for local (F‐test, P = 0.01). For all clustering methods, we found a large systematic underestimation of flow compared with 2D PCMRI (16.1–22.3 ml/min).Data ConclusionA locally adapted threshold value gives a more stable result compared with a globally fixed threshold. 4D flow with the proposed segmentation method has the potential to become a useful reliable clinical tool for assessment of blood flow in the major cerebral arteries.Level of Evidence: 2Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2019;50:511–518.
Diffusion kurtosis imaging‐derived histogram metrics for prediction of KRAS mutation in rectal adenocarcinoma: Preliminary findings
Authors: Cui Yanfen , Cui Xue'e , Yang Xiaotang , Zhuo Zhizheng , Du Xiaosong , Xin Lei , Yang Zhao , Cheng Xintao 
Published: January 2019

BackgroundAlthough histological examination is the standard method for assessing genetic status, the development of a noninvasive method, which can display the heterogeneity of the whole tumor to supplement genotype analysis, might be important for personalized treatment strategies.PurposeTo evaluate the potential role of diffusion kurtosis imaging (DKI)‐derived parameters using histogram analysis derived from whole‐tumor volumes for prediction of the status of KRAS mutations in patients with rectal adenocarcinoma.Study TypeRetrospective.SubjectsIn all, 148 consecutive patients with histologically confirmed rectal adenocarcinoma who were treated at our institution.SequenceDKI was performed with a 3.0 T MRI system using a single‐shot echo‐planar imaging sequence with b values of 0, 700, 1400, and 2100 sec/mm2.AssessmentD, K, and apparent diffusion coefficient (ADC) values were measured using whole‐tumor volume histogram analysis and were compared between different KRAS mutations status.Statistical TestsStudent's t‐test or Mann–Whitney U‐test, and receiver operating characteristic (ROC) curves were used for statistical analysis.ResultsAll the percentile metrics of ADC and D values were significantly lower in the mutated group than those in the wildtype group (all P < 0.05), except for the minimum value of ADC and D (both P > 0.05), while K‐related percentile metrics were higher in the mutated group compared with those in the wildtype group (all P < 0.05). Regarding the comparison of the diagnostic performance of all the histogram metrics, K75th showed the highest AUC value of 0.871, and the corresponding values for sensitivity, specificity, positive predictive value, and negative predictive value were 81.43%, 78.21%, 77.03%, and 82.43%, respectively.Data ConclusionDKI metrics with whole‐tumor volume histogram analysis is associated with KRAS mutations, and thus may be useful for predicting the KRAS status of rectal cancers for guiding targeted therapy.Level of Evidence: 3Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2019;50:930–939.
New directions for exploring the consequences of proactive behaviors: Introduction to the special issue
Authors: Liu Wu , Tangirala Subrahmaniam , Lee Cynthia , Parker Sharon K. 
Published: January 2019

SummaryThis special issue introduces new directions for exploring the consequences of proactive behaviors. The authors summarize the new scopes of consequences, new social contexts, and new methods in this exploration. They also identify several limitations of the existing literature and call for more future research in this stream.
Imaging of the subtalar joint: A novel approach to an old problem
Authors: Krähenbühl Nicola , Lenz Amy L. , Lisonbee Rich , Deforth Manja , Zwicky Lukas , Hintermann Beat , Saltzman Charles L. , Anderson Andrew E. , Barg Alexej 
Published: January 2019

ABSTRACTEvaluation of the subtalar joint using conventional radiographs is difficult. The purpose of this study was to assess how the posterior facet of the subtalar joint is projected on eight standard radiographic views of the foot and ankle. Weightbearing computed tomography (CT) scans of 27 volunteers without ankle pathology were performed. Eight standard views of the foot and ankle (antero‐posterior [AP] view, mortise view, subtalar view, four different Broden views) were reconstructed using digitally reconstructed radiographs (DRRs). The appearance of the posterior facet of the subtalar joint was assessed for each view. In addition, the position of the joint line was projected onto three‐dimensional (3‐D) models of the calcaneus. We found (i) on the AP view of the ankle joint, the posterior part of the posterior facet is visualized and appears convex (calcaneal side); (ii) on the mortise view of the ankle joint, a slightly more anterior part (compared to the AP view) is visualized and appears either convex or flat; (iii) on the subtalar view, the anterior part of the posterior facet is visualized and appears either convex, flat or concave; and (iv) using the Broden views, the posterior and anterior part of the posterior facet can be visualized. This study clarifies which parts of the posterior facet of the subtalar joint are visualized on eight standard views of the foot and ankle. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Exploring intersectionality issues in entrepreneurial finance: Policy responses and future research directions
Authors: Scott Jonathan M. , Hussain Javed 
Published: January 2019

AbstractEntrepreneurial finance scholars (and policy makers) need to adopt an intersectional approach to their analysis (and policymaking) and pay more attention to the interplay between the owner‐manager characteristics of ethnicity/race, gender, and social class. As most literature on entrepreneurial finance treats ethnicity/race, gender, and class separately, an intersectional approach to analysis is complex, whether social (race, gender, and social class) or situational characteristics (entrepreneur vs. migrant/social or health‐care worker). Women, ethnic minorities, and working‐class people are disadvantaged when seeking finance. We integrate the literature and propose intersectionality as a framework for policy makers, because the interplay between these characteristics can be addressed to develop innovative methods of finance.
Scalping of aroma compounds from food simulants into polyethylene terephthalate laminated steel
Authors: Yuan Shaofeng , Zhang Yichi , Xie Yunfei , Guo Yahui , Cheng Yuliang , Qian He , Liu Zhigang , Shen Junjie , Yao Weirong 
Published: January 2019

AbstractBACKGROUNDAroma scalping is a very common problem and can affect the sensory quality of packaged food. To study the aroma scalping characteristics of polyethylene terephthalate laminated steel (PET‐LS), the sorption kinetics of six common aroma compounds (2‐pentanone, 2‐heptanone, hexanal, citral, butyl acetate, isopentyl acetate) in foods were assessed for drawn–redrawn cans made with PET‐LS.RESULTSStorage temperature and initial concentration were proved as important factors to affect compound sorption and diffusion for flavors. The correlation between logarithm of equilibrium absorption ln M∞ and reciprocal of absolute temperature 1/T showed good linear relationship (R2 = 0.9380–0.9998) at 4 °C, 20 °C and 50 °C, and the M∞ obtained by the experiment was very close to the predicted value at 37 °C. At low initial concentration (below 500 µL L−1), the absorption capacity and initial concentration showed a slow linear growth trend, whereas there was a rapid change at high initial concentration. The values of diffusion coefficient D were on the order of 10−11–10−12 m2 day−1, which were lower than reported for other polymer materials (linear low‐density polyethylene, polybutylene succinate, polylactic acid).CONCLUSIONThe equilibrium absorption amount of each flavor component was dependent on the temperature under the same concentration (500 µL L−1). The Fickian diffusion model was used for fitting the experimental kinetics values satisfactorily (R2 = 0.9158–0.9885). © 2019 Society of Chemical Industry
Healthy diet: a step toward a sustainable diet by reducing water footprint
Authors: Sobhani Seyyed Reza , Rezazadeh Arezoo , Omidvar Nasrin , Eini‐Zinab Hassan 
Published: January 2019

AbstractBACKGROUNDThis paper aims to assess different scenarios that reduce water use by following healthy diet recommendations. In this study, a food frequency questionnaire was used to assess the usual food intake of a sample of 723 individuals, aged 20–64 years, from Urmia, Iran. In order to calculate water use for production of food items, the water footprint method was applied. A linear programming technique was used to find a healthy diet with low blue water footprint in three scenarios.RESULTSThe biggest decline in water use compared with real intake (57%) was found in scenario 1, where the model‐generated consider energy intake equal to usual energy intake. In scenario 2, in which the proportion of each food group was allowed to be in accordance with the Iranian food pyramid, the reduction in water use was less than for scenario 1 (47%). In scenario 3, where the Recommended Dietary Allowance values were also added to the set of model restrictions, the water usage was 51% of the real diet.CONCLUSIONA healthy diet with greater proportion of energy from fruit and dairy instead of a diet with high proportion of energy from ‘meat–fish–poultry–eggs’ and ‘bread–cereal–rice–pasta’ can supply all Recommended Dietary Allowances while reducing water use. © 2019 Society of Chemical Industry
Partial propane extraction of aromatic compounds from dehydrated basils (Ocimum Lamiaceae)
Authors: Kalkan Elif , Maness Niels O , Chrz Donna R 
Published: January 2019

AbstractBACKGROUNDMany conventional extraction methods for basils (Ocimum sp. Lamiaceae) produce only the extract as a usable product and leave the extracted herb as a waste product. We demonstrate partial extraction of chemically and morphologically diverse basil cultivars using propane at low temperature (20–27 °C) and pressure (950–1200 kPa) and evaluate the process for production of dual products, the extracted herb (raffinate) and the herb extract in terms of aromatic content and color.RESULTSThe extracts contained aromatic compounds that were characteristic of but not always identical in terms of relative abundance to the dehydrated herb. Extraction decreased total aromatics in the raffinate by 12–43% but the individual aromatic proportions remained essentially the same, preserving flavor characteristics of the raffinate. Color was mostly unchanged by the extraction process.CONCLUSIONPartial propane extraction resulted in two useful basil products (an extract and extraction raffinate). Aromatic extractability was tissue and cultivar dependent for basils. Therefore, partial extraction protocols should be optimized according to cultivar/plant tissue abundance to provide consistent aromatic intensity of these potential food products. © 2019 Society of Chemical Industry
Development of a highly sensitive gas chromatography–mass spectrometry method preceded by solid‐phase microextraction for the analysis of propofol in low‐volume cerebral microdialysate samples
Authors: Guntner Armin Sebastian , Stöcklegger Simon , Kneidinger Michael , Illievich Udo , Buchberger Wolfgang 
Published: January 2019

AbstractTo date, the commonly used intravenous anesthetic propofol has been widely studied, and fundamental pharmacodynamic and pharmacokinetic characteristics of the drug are known. However, propofol has not yet been quantified in vivo in the target organ, the human brain. Here, cerebral microdialysis offers the unique opportunity to sample propofol in the living human organism. Therefore, a highly sensitive analytical method for propofol quantitation in small sample volumes of 30 μL, based on direct immersion solid‐phase microextraction was developed. Preconcentration was followed by gas chromatographic separation and mass spectrometric detection of the compound. This optimized method provided a linear range between the lower limit of detection (50 ng/L) and 200 μg/L. Matrix‐matched calibration was used to compensate recovery issues. A precision of 2.7% relative standard deviation between five consecutive measurements and an interday precision of 6.4% relative standard deviation could be achieved. Furthermore, the permeability of propofol through a cerebral microdialysate system was tested. In summary, the developed method to analyze cerebral microdialysate samples, allows the in vivo quantitation of propofol in the living human brain. Additionally the calculation of extracellular fluid levels is enabled since the recovery of the cerebral microdialysis regarding propofol was determined.
Cost savings associated with an outpatient otolaryngology telemedicine clinic
Authors: Philips Ramez , Seim Nolan , Matrka Laura , Locklear Brittany , Moberly Aaron C. , Inman Mark , Essig Garth 
Published: January 2019

ObjectiveTo test the null hypothesis that there is no difference in patient cost savings between the telemedicine and traditional face‐to‐face approach. The second objective was to assess the financial impact on the peripheral healthcare system, as compared with staffing a conventional clinic with “on‐site” otolaryngologist.MethodsTwenty‐one patients were enrolled. To assess “patient‐benefit” cost savings, a model was formulated that would utilize a certified nurse practitioner (CNP) to conduct a general otolaryngology clinic at the peripheral site, as compared with having to travel to the tertiary referral center. A “peripheral site‐benefit” cost analysis was performed to assess costs of initiating and operating a telemedicine clinic at the peripheral site, compared with having an on‐site otolaryngologist.ResultsThe total patient‐benefit cost savings would be $182.09 per patient per encounter and $333.22 per patient annually. The fixed cost to the peripheral site to initiate the telemedicine system was $9,895. Two hundred sixty telemedicine encounters would be needed to offset the initial cost, and 537 encounters would be needed to surpass revenue of the conventional clinic.ConclusionA real‐time telemedicine otolaryngology clinic provides significant cost savings for both patients and the peripheral healthcare system. This pilot study supports telemedicine as a cost‐effective approach to providing general otolaryngology care to rural patients.Level of Evidence4
Incorporation of Benzoxazine Pendants in Polymer Chains: A Simple Approach to Add‐Up Multi‐Responsive Functions
Authors: Niyomsin Sorapat , Hirai Tomoyasu , Takahara Atsushi , Chirachanchai Suwabun 
Published: January 2019

AbstractExternal stimuli responsive polymers can be derived from the functional side group in copolymers. Benzoxazine dimer is a good candidate for expressing multi‐responsive properties based on the type of phenol in combination with its metal complexation. The present work proposes a vinyl monomer containing a benzoxazine pendant, which contains an azo group as the functional monomer. The copolymerization with methylmethacrylate (MMA) via atom transfer radical polymerization leads to a block copolymer, specifically, PA‐Azo‐C3‐b‐PMMA, which forms uniform nanoparticles. The ring opening of benzoxazine monomer results in dimer pendants. The copolymer obtained, PA‐Azo‐C3‐b‐PMMA, shows multi‐responsive functions in terms of metal ion complexation, and UV responsiveness through the dimer pendants and azobenzene groups. The UV exposure results in loss of uniformity of the nanoparticles as well as a decrease in size. This work demonstrates the role of benzoxazine pendants in developing PMMA copolymer showing external stimuli responsive functions.
Evaluation of the detection of GBA missense mutations and other variants using the Oxford Nanopore MinION
Authors: Leija‐Salazar Melissa , Sedlazeck Fritz J. , Toffoli Marco , Mullin Stephen , Mokretar Katya , Athanasopoulou Maria , Donald Aimee , Sharma Reena , Hughes Derralynn , Schapira Anthony H.V. , Proukakis Christos 
Published: January 2019

AbstractBackgroundMutations in GBA cause Gaucher disease when biallelic and are strong risk factors for Parkinson's disease when heterozygous. GBA analysis is complicated by the nearby pseudogene. We aimed to design and validate a method for sequencing GBA using long reads.MethodsWe sequenced GBA on the Oxford Nanopore MinION as an 8.9 kb amplicon from 102 individuals, including patients with Parkinson's and Gaucher diseases. We used NanoOK for quality metrics, NGMLR to align data (after comparing with GraphMap), Nanopolish and Sniffles to call variants, and WhatsHap for phasing.ResultsWe detected all known missense mutations in these samples, including the common p.N409S (N370S) and p.L483P (L444P) in multiple samples, and nine rarer ones, as well as a splicing and a truncating mutation, and intronic SNPs. We demonstrated the ability to phase mutations, confirm compound heterozygosity, and assign haplotypes. We also detected two known risk variants in some Parkinson's patients. Rare false positives were easily identified and filtered, with the Nanopolish quality score adjusted for the number of reads a very robust discriminator. In two individuals carrying a recombinant allele, we were able to detect and fully define it in one carrier, where it included a 55‐base pair deletion, but not in another one, suggesting a limitation of the PCR enrichment method. Missense mutations were detected at the correct zygosity, except for the case where the RecNciI one was missed.ConclusionThe Oxford Nanopore MinION can detect missense mutations and an exonic deletion in this difficult gene, with the added advantages of phasing and intronic analysis. It can be used as an efficient research tool, but additional work is required to exclude all recombinants.
Explicit versus implicit front advancing schemes for the simulation of hydraulic fracture growth
Authors: Zia Haseeb , Lecampion Brice 
Published: January 2019

SummaryThe proper computation of the time evolution of the fracture front is the main challenge of three‐dimensional (3D) hydraulic fracture growth simulation. We discuss explicit and implicit variants of a hydraulic fracture propagation scheme based on a level set representation of the fracture. Such a scheme couples a finite discretization of the governing equations and the near‐tip hydraulic fracture asymptotes. We benchmark the accuracy, robustness, and stability of these different front advancing schemes on a number of test cases. Our results indicate a large computational gain of the explicit scheme at the expense of a slightly less accurate solution (few percent less accuracy over few time steps) when crossing heterogeneities. The predictor corrector scheme combines at least an approximately 25% computational gain while retaining the stability and accuracy of the fully implicit version of the scheme in all cases.
Fast data acquisition techniques in magnetic resonance spectroscopic imaging
Authors: Vidya Shankar Rohini , Chang John C. , Hu Houchun H. , Kodibagkar Vikram D. 
Published: January 2019

Magnetic resonance spectroscopic imaging (MRSI) is an important technique for assessing the spatial variation of metabolites in vivo. The long scan times in MRSI limit clinical applicability due to patient discomfort, increased costs, motion artifacts, and limited protocol flexibility. Faster acquisition strategies can address these limitations and could potentially facilitate increased adoption of MRSI into routine clinical protocols with minimal addition to the current anatomical and functional acquisition protocols in terms of imaging time. Not surprisingly, a lot of effort has been devoted to the development of faster MRSI techniques that aim to capture the same underlying metabolic information (relative metabolite peak areas and spatial distribution) as obtained by conventional MRSI, in greatly reduced time. The gain in imaging time results, in some cases, in a loss of signal‐to‐noise ratio and/or in spatial and spectral blurring.This review examines the current techniques and advances in fast MRSI in two and three spatial dimensions and their applications. This review categorizes the acceleration techniques according to their strategy for acquisition of the k‐space. Techniques such as fast/turbo‐spin echo MRSI, echo‐planar spectroscopic imaging, and non‐Cartesian MRSI effectively cover the full k‐space in a more efficient manner per TR. On the other hand, techniques such as parallel imaging and compressed sensing acquire fewer k‐space points and employ advanced reconstruction algorithms to recreate the spatial‐spectral information, which maintains statistical fidelity in test conditions (ie no statistically significant differences on voxel‐wise comparisions) with the fully sampled data. The advantages and limitations of each state‐of‐the‐art technique are reviewed in detail, concluding with a note on future directions and challenges in the field of fast spectroscopic imaging.