bluuebunny/crossref_metadata_2025_split huggingface dataset:
The smallest eigenvalue of large Hankel matrices generated by a deformed Laguerre weight
Authors: Zhu Mengkun , Emmart Niall , Chen Yang , Weems Charles 
Published: March 2019

We study the asymptotic behavior of the smallest eigenvalue, λN, of the Hankel (or moments) matrix denoted by
, with respect to the weight
. An asymptotic expression of the polynomials orthogonal with w(x) is established. Using this, we obtain the specific asymptotic formulas of λN in this paper.Applying a parallel numerical algorithm, we get a variety of numerical results of λN corresponding to our theoretical calculations.
Fucoxanthin Protects against oxLDL‐Induced Endothelial Damage via Activating the AMPK‐Akt‐CREB‐PGC1α Pathway
Authors: Ou Hsiu‐Chung , Chou Wan‐Ching , Chu Pei‐Ming , Hsieh Pei‐Ling , Hung Ching‐Hsia , Tsai Kun‐Ling 
Published: March 2019

ScopeAtherosclerotic cardiovascular disease is the most prevalent cause of mortality and morbidity. Fucoxanthin (FX) possesses anti‐hypertensive and anti‐obesity properties. However, the molecular mechanisms underlying the inhibitory effects of FX on oxidized low‐density lipoprotein (oxLDL)‐induced oxidative injuries in human endothelial cells are still largely unknown. This study aims to test the hypothesis that FX protects against oxLDL‐induced oxidative stress by upregulating AMP‐activated protein kinase (AMPK) and to explore the roles of cAMP response element binding protein (CREB) and peroxisome proliferator‐activated receptor gamma coactivator‐1α (PGC‐1α).Methods and ResultsHuman umbilical vein endothelial cells are treated with oxLDL in the presence or absence of FX. FX significantly increases AMPK phosphorylation. In addition, FX diminishes oxLDL‐mediated nicotinamide adenine dinucleotide phosphate oxidase activation by inhibiting protein kinase C and subsequently inducing reactive oxygen species generation and impairing the activity of the endogenous antioxidant enzyme superoxidase dismutase. Furthermore, FX restores oxLDL‐mediated dephosphorylation of phosphoinositide‐3‐kinase/Akt and decreases CREB and PGC‐1α expression to nearly normal levels. Moreover, FX ameliorates the oxLDL‐mediated suppression of mitochondrial function and apoptosis.ConclusionThese findings provide new insights into the possible molecular mechanisms by which FX mitigates oxLDL‐induced endothelial oxidative stress and mitochondrial dysfunction.
A convolutional neural network algorithm for automatic segmentation of head and neck organs at risk using deep lifelong learning
Authors: Chan Jason W. , Kearney Vasant , Haaf Samuel , Wu Susan , Bogdanov Madeleine , Reddick Mariah , Dixit Nayha , Sudhyadhom Atchar , Chen Josephine , Yom Sue S. , Solberg Timothy D. 
Published: March 2019

PurposeThis study suggests a lifelong learning‐based convolutional neural network (LL‐CNN) algorithm as a superior alternative to single‐task learning approaches for automatic segmentation of head and neck (OARs) organs at risk.Methods and materialsLifelong learning‐based convolutional neural network was trained on twelve head and neck OARs simultaneously using a multitask learning framework. Once the weights of the shared network were established, the final multitask convolutional layer was replaced by a single‐task convolutional layer. The single‐task transfer learning network was trained on each OAR separately with early stoppage. The accuracy of LL‐CNN was assessed based on Dice score and root‐mean‐square error (RMSE) compared to manually delineated contours set as the gold standard. LL‐CNN was compared with 2D‐UNet, 3D‐UNet, a single‐task CNN (ST‐CNN), and a pure multitask CNN (MT‐CNN). Training, validation, and testing followed Kaggle competition rules, where 160 patients were used for training, 20 were used for internal validation, and 20 in a separate test set were used to report final prediction accuracies.ResultsOn average contours generated with LL‐CNN had higher Dice coefficients and lower RMSE than 2D‐UNet, 3D‐Unet, ST‐ CNN, and MT‐CNN. LL‐CNN required ~72 hrs to train using a distributed learning framework on 2 Nvidia 1080Ti graphics processing units. LL‐CNN required 20 s to predict all 12 OARs, which was approximately as fast as the fastest alternative methods with the exception of MT‐CNN.ConclusionsThis study demonstrated that for head and neck organs at risk, LL‐CNN achieves a prediction accuracy superior to all alternative algorithms.
Accuracy of registration algorithms in subtraction CT of the lungs: A digital phantom study
Authors: Grob Dagmar , Oostveen Luuk , Rühaak Jan , Heldmann Stefan , Mohr Brian , Michielsen Koen , Dorn Sabrina , Prokop Mathias , Kachelrieβ Marc , Brink Monique , Sechopoulos Ioannis 
Published: March 2019

PurposeThe purpose of this study was to assess, using an anthropomorphic digital phantom, the accuracy of algorithms in registering precontrast and contrast‐enhanced computed tomography (CT) chest images for generation of iodine maps of the pulmonary parenchyma via temporal subtraction.Materials and methodsThe XCAT phantom, with enhanced airway and pulmonary vessel structures, was used to simulate precontrast and contrast‐enhanced chest images at various inspiration levels and added CT simulation for realistic system noise. Differences in diaphragm position were varied between 0 and 20 mm, with the maximum chosen to exceed the 95th percentile found in a dataset of 100 clinical subtraction CTs. In addition, the influence of whole body movement, degree of iodine enhancement, beam hardening artifacts, presence of nodules and perfusion defects in the pulmonary parenchyma, and variation in noise on the registration were also investigated. Registration was performed using three lung registration algorithms — a commercial (algorithm A) and a prototype (algorithm B) version from Canon Medical Systems and an algorithm from the MEVIS Fraunhofer institute (algorithm C). For each algorithm, we calculated the voxel‐by‐voxel difference between the true deformation and the algorithm‐estimated deformation in the lungs.ResultsThe median absolute residual error for all three algorithms was smaller than the voxel size (1.0 × 1.0 × 1.0 mm3) for up to an 8 mm diaphragm difference, which is the average difference in diaphragm levels found clinically, and increased with increasing difference in diaphragm position. At 20 mm diaphragm displacement, the median absolute residual error after registration was 0.85 mm (interquartile range, 0.51–1.47 mm) for algorithm A, 0.82 mm (0.50–1.40 mm) for algorithm B, and 0.91 mm (0.54–1.52 mm) for algorithm C. The largest errors were seen in the paracardiac regions and close to the diaphragm. The impact of all other evaluated conditions on the residual error varied, resulting in an increase in the median residual error lower than 0.1 mm for all algorithms, except in the case of whole body displacements for algorithm B, and with increased noise for algorithm C.ConclusionMotion correction software can compensate for respiratory and cardiac motion with a median residual error below 1 mm, which was smaller than the voxel size, with small differences among the tested registration algorithms for different conditions. Perfusion defects above 50 mm will be visible with the commercially available subtraction CT software, even in poorly registered areas, where the median residual error in that area was 7.7 mm.
Quantitative assessment of breast density using transmission ultrasound tomography
Authors: Wiskin James , Malik Bilal , Natesan Rajni , Lenox Mark 
Published: March 2019

PurposeBreast density is important in the evaluation of breast cancer risk. At present, breast density is evaluated using two‐dimensional projections from mammography with or without tomosynthesis using either (a) subjective assessment or (b) a computer‐aided approach. The purpose of this work is twofold: (a) to establish an algorithm for quantitative assessment of breast density using quantitative three‐dimensional transmission ultrasound imaging; and (b) to determine how these quantitative assessments compare with both subjective and objective mammographic assessments of breast density.MethodsWe described and verified a threshold‐based segmentation algorithm to give a quantitative breast density (QBD) on ultrasound tomography images of phantoms of known geometric forms. We also used the algorithm and transmission ultrasound tomography to quantitatively determine breast density by separating fibroglandular tissue from fat and skin, based on imaged, quantitative tissue characteristics, and compared the quantitative tomography segmentation results with subjective and objective mammographic assessments.ResultsQuantitative breast density (QBD) measured in phantoms demonstrates high quantitative accuracy with respect to geometric volumes with average difference of less than 0.1% of the total phantom volumes. There is a strong correlation between QBD and both subjective mammographic assessments of Breast Imaging ‐ Reporting and Data System (BI‐RADS) breast composition categories and Volpara density scores — the Spearman correlation coefficients for the two comparisons were calculated to be 0.90 (95% CI: 0.71–0.96) and 0.96 (95% CI: 0.92–0.98), respectively.ConclusionsThe calculation of breast density using ultrasound tomography and the described segmentation algorithm is quantitatively accurate in phantoms and highly correlated with both subjective and Food and Drug Administration (FDA)‐cleared objective assessments of breast density.
A depth average SPH model including μ(I) rheology and crushing for rock avalanches
Authors: Longo Alberto , Pastor Manuel , Sanavia Lorenzo , Manzanal Diego , Martin Stickle Miguel , Lin Chuan , Yague Angel , Tayyebi Saeid Moussavi 
Published: March 2019

SummaryClassical depth‐integrated smoothed particle hydrodynamics (SPH) models for avalanches are extended in the present work to include a μ(I)− rheological model enriched with a fragmentation law. With this improvement, the basal friction becomes grain distribution dependent. Rock avalanches, where grain distribution tends to change with time while propagating, are the appropriate type of landslide to apply the new numerical proposal. The μ(I)− rheological models considered in the present work are those of Hatano and Gray, combined with two different fragmentation laws, a hyperbolic and a fractal‐based law. As an application, Frank avalanche, which took place in Canada in 1903, is analyzed under the scope of the present approach, focusing in the influence of the rheological and fragmentation laws in the evolution of the avalanche.
Randomized, open‐label, tolterodine‐controlled, comparative study of the novel antimuscarinic agent imidafenacin in patients with overactive bladder
Authors: Pushkar Dmitry Y. , Kasyan George R. , Kolontarev Konstantin B. , Sharvadze Georgy G. , Mukhametshina Elvira I. 
Published: March 2019

AbstractBackgroundThe role of the selective antimuscarinic imidafenacin in Caucasian patients with overactive bladder (OAB) has not been previously assessed.ObjectiveTo evaluate the safety and efficacy of imidafenacin 0.2 mg vs tolterodine 4 mg per day in patients with OAB.Design Setting and ParticipantsThis study was a randomized, open‐label, tolterodine‐controlled, comparative multicenter trial of 300 randomized patients with OAB symptoms for 12 weeks with full analysis of 289 patients.Outcome Measurements and Statistical AnalysisBased on 5‐day bladder diaries, the primary efficacy endpoint was the change in the mean number of micturitions per day. The secondary endpoints were the change in the mean incontinence episodes, voiding frequency, the OAB Awareness Tool score, and the European Quality of Life Questionnaire (EQ‐5D) score. The superiority of tolterodine over imidafenacin in the mean number of micturitions/24 hours was the null hypothesis.Results and LimitationThe median age was 46.6 years, and 82% of patients were female. After treatment, the change in the mean number of incontinence episodes was −2.1 ± 2.2 in the imidafenacin group and −1.9 ± 1.8 in the tolterodine group (P = .001). The change in the mean number of daytime incontinence episodes was −1.7 ± 1.7 and −1.5 ± 1.4 (
P = .01). The OAB Awareness Tool score decreased by 14.2 ± 8.5 and 14.5 ± 8.0, respectively (
P = 0.5). Most adverse events were mild and resolved without treatment.ConclusionsThe clinical efficacy and safety of imidafenacin are not inferior to those of tolterodine for the treatment of Caucasian patients with OAB.Patient SummaryImidafenacin is as effective as tolterodine for the treatment of OAB.
Distributionally robust project crashing with partial or no correlation information
Authors: Ahipasaoglu Selin Damla , Natarajan Karthik , Shi Dongjian 
Published: March 2019

AbstractCrashing is shortening the project makespan by reducing activity times in a project network by allocating resources to them. Activity durations are often uncertain and an exact probability distribution itself might be ambiguous. We study a class of distributionally robust project crashing problems where the objective is to optimize the first two marginal moments (means and SDs) of the activity durations to minimize the worst‐case expected makespan. Under partial correlation information and no correlation information, the problem is solvable in polynomial time as a semidefinite program and a second‐order cone program, respectively. However, solving semidefinite programs is challenging for large project networks. We exploit the structure of the distributionally robust formulation to reformulate a convex‐concave saddle point problem over the first two marginal moment variables and the arc criticality index variables. We then use a projection and contraction algorithm for monotone variational inequalities in conjunction with a gradient method to solve the saddle point problem enabling us to tackle large instances. Numerical results indicate that a manager who is faced with ambiguity in the distribution of activity durations has a greater incentive to invest resources in decreasing the variations rather than the means of the activity durations.
Painting Country: Spatial, Somatic and Linguistic Experience in Central Australian Aboriginal Art
Authors: Tavendale Olwyn 
Published: March 2019

ABSTRACTA demonstration that the spatial experience informing some Central Australian Aboriginal art is topographically precise brings into question the relevance of structuralist methodologies for appraising these maps of country. Qualitative aspects of spatial, somatic, linguistic and emotional experiences are found to inform the way‐finding depicted in paintings by artists of three language groups.
Prechemotherapy Levels of Plasma Dehydroepiandrosterone and Its Sulfated Form as Predictors of Cancer‐Related Cognitive Impairment in Patients with Breast Cancer Receiving Chemotherapy
Authors: Toh Yi Long , Shariq Mujtaba Juliana , Bansal Sumit , Yeo Angie , Shwe Maung , Lau Aik Jiang , Chan Alexandre 
Published: March 2019

Study ObjectiveDehydroepiandrosterone (DHEA) and its sulfated form (DHEAS)—jointly referred to asDHEA(S)—are neurosteroids known to regulate brain development and function that have been found to be positively correlated with cognitive function. It is unknown whether prechemotherapy plasmaDHEA(S) levels are associated with the onset of cancer‐related cognitive impairment (CRCI). The objective of this study was to evaluate whether an association exists between prechemotherapy plasmaDHEA(S) levels and onset ofCRCIin patients with breast cancer receiving chemotherapy.DesignMulticenter, prospective cohort study.SettingTwo specialized cancer centers in Singapore.PatientsEighty‐one patients with early‐stage breast cancer (stages I–III) who had no prior exposure to chemotherapy and/or radiotherapy and were scheduled to receive anthracycline‐based or taxane‐based chemotherapy treatment with curative intent.Measurements and Main ResultsPatients completed assessments for self‐perceived and objective cognitive function at three time points: prechemotherapy (T1), during chemotherapy (T2), and after chemotherapy (T3). Plasma samples were collected prior to chemotherapy, andDHEA(S) levels were quantified by using ultra–high‐performance liquid chromatography–tandem mass spectrometry. Multivariable logistic regression was used to adjust for clinically important factors and to evaluate the association between prechemotherapy plasmaDHEA(S) levels andCRCI. Mean ± SDage was 48.9 ± 9.3 years, with 27.8% of patients experiencing clinically significant cognitive impairment based on global Functional Assessment of Cancer Therapy–Cognitive Function scores. The mean ± SDprechemotherapy plasmaDHEASandDHEAlevels were 1.61 ± 0.91 μmol/L and 19.21 ± 13.13 nmol/L, respectively. PrechemotherapyDHEASlevels were found to be associated with impairment in the self‐perceived cognitive domains of verbal fluency (adjusted odds ratio [OR] 0.27, 95% confidence interval [CI] 0.08–0.96) and mental acuity (adjustedOR0.25, 95%CI0.08–0.74). Conversely,DHEAlevels were not associated with impairment in any cognitive subdomains.ConclusionOur findings suggest that patients with higher prechemotherapyDHEASlevels had lower odds of developing self‐perceived cognitive impairment. Future studies are required to further investigate the effect ofDHEA(S) on specific cognitive domains and to validate our findings in independent cohorts.
Fixed‐Dose Four‐Factor Prothrombin Complex Concentrate for Vitamin K Antagonist Reversal: Does One Dose Fit All?
Authors: Schwebach Alyson A. , Waybright Ryan A. , Johnson Thomas J. 
Published: March 2019

Four‐factor prothrombin complex concentrate (4F‐PCC) has emerged as the preferred option for emergent reversal of vitamin K antagonists (VKAs); however, the optimal dosing strategy is unknown. Although several studies have attempted to determine the optimal dose of 4F‐PCC using a variety of dosing regimens, no dosing strategy has been found to be superior. Many of these studies have evaluated a low, fixed dose of 4F‐PCC rather than individualized dosing as recommended in product labeling. The purpose of this review was to evaluate the efficacy and safety of various fixed‐dose strategies of 4F‐PCC for emergent VKA reversal and to assess limitations of the existing literature. A search of the PubMed database was performed from the earliest available date through 2018 for relevant articles describing fixed‐dose 4F‐PCC for VKA reversal. Reference lists of relevant articles were also manually reviewed. Most currently available studies are primarily observational and heterogeneous in design. A very low fixed dose of 500 IU is likely inadequate for successful VKA reversal, but increased fixed doses of 1000–1500 IU have found some degree of success and may be considered for VKA reversal. However, many of these studies consistently identified a trend toward international normalized ratio (INR) reversal failure in patients presenting with high baseline INR values or intracranial hemorrhage, suggesting that higher 4F‐PCC doses are needed in these patients. Available studies are underpowered to determine whether a dose‐dependent association with thrombotic risk exists. Additional large, randomized studies are needed to determine the optimal dosing strategy and ascertain the role for fixed‐dose 4F‐PCC.
The effect of poly(butylene succinate) content on the structure and thermal and mechanical properties of its blends with polylactide
Authors: Ostrowska Justyna , Sadurski Waldemar , Paluch Magdalena , Tyński Piotr , Bogusz Jakub 
Published: March 2019

AbstractPoly(butylene succinate) (PBS) and polylactide (PLA) were blended in a co‐rotating twin‐screw extruder with various contents of PBS from 0 to 100 wt%. The effect of PBS content on the thermal and mechanical properties of PBS/PLA blends was investigated by using DSC, softening point measurements, a Charpy impact test and tensile testing. The Fourier transform infrared spectra showed that the polymers are immiscible, but the addition of PBS could modify the PLA structure in PBS/PLA blends by changing the content of amorphous and crystalline phases. In addition, the cold crystallization temperature of PLA in blends decreases in comparison with pure PLA, which shows that PBS could have a plasticizing effect on PLA. This is confirmed by the results of DSC analysis. The mechanical properties of the blends depend on the percentage of PBS addition. Typically, the mechanical properties of PBS/PLA blends are intermediate between the properties of the polyesters from which they are obtained. However, in some cases unexpected changes in mechanical properties of the blends were observed. For example, the elongation at break for a PBS/PLA blend containing 10 wt% PLA is higher than for pure PBS. © 2019 Society of Chemical Industry
Quantitative, Label‐Free Proteomics in the Symptomatic Niemann–Pick, Type C1 Mouse Model Using Standard Flow Liquid Chromatography and Thermal Focusing Electrospray Ionization
Authors: Pergande Melissa R. , Nguyen Thu T. A. , Haney‐Ball Carol , Davidson Cristin D. , Cologna Stephanie M. 
Published: March 2019

AbstractNiemann–Pick disease, type C1 (NPC1) is a fatal, autosomal recessive, neurodegenerative disorder caused by mutations in the NPC1 gene. As a result, there is accumulation of unesterified cholesterol and sphingolipids in the late endosomal/lysosomal system. This abnormal accumulation results in a cascade of pathophysiological events including progressive, cerebellar neurodegeneration, among others. While significant progress has been made to better understand NPC1, the downstream effects of cholesterol storage and the major mechanisms that drive neurodegeneration remain unclear. In the current study, a) the use of a commercial, highly efficient standard flow‐ESI platform for protein biomarker identification is implemented and b) protein biomarkers are identified and evaluated at a terminal time point in the NPC1 null mouse model. In this study, alterations are observed in proteins related to fatty acid homeostasis, calcium binding and regulation, lysosomal regulation, and inositol biosynthesis and metabolism, as well as signaling by Rho family GTPases. New observations from this study include altered expression of Pcp2 and Limp2 in Npc1 mutant mice relative to control, with Pcp2 exhibiting multiple isoforms and specific to the cerebella. This study provides valuable insight into pathways altered in the late‐stage pathophysiology of NPC1.
Removal of methylene blue dye from aqueous solution by semi‐interpenetrating polymer network hybrid hydrogel: Optimization through Taguchi method
Authors: Yilmaz Elif , Guzel Kaya Gulcihan , Deveci Huseyin 
Published: March 2019

ABSTRACTIn this study, sodium humate/poly(acrylamide‐co‐methacrylic acid)/kaolin semi‐interpenetrating polymer network hybrid hydrogel was synthesized as an effective adsorbent for the removal of methylene blue. The morphological and structural properties, and swelling behavior in distilled water and various environments of hybrid hydrogel were investigated with different analyses and tests. The equilibrium swelling percent of hybrid hydrogel reached to 37,000% in 240 min. The parameters (agitation time, concentration, dose, temperature, and pH) affecting adsorption process for methylene blue were optimized using Taguchi method. The data obtained in optimum conditions were well fitted to Langmuir adsorption isotherm and maximum adsorption capacity was determined as 833. 33 mg/g. In the light of the results, the utilization of hybrid hydrogel with high swelling capacity is foreseen as a favored adsorbent in several separation processes. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1070–1078