bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic contrast‐enhanced imaging in localizing local recurrence of prostate cancer after radiotherapy: Limited added value for readers of varying level of experience
Authors: Luzurier Anna , Jouve De Guibert Paul‐Hugo , Allera Alexandre , Feldman Sarah F. , Conort Pierre , Simon Jean Marc , Mozer Pierre , Compérat Eva , Boudghene Franck , Servois Vincent , Lucidarme Olivier , Granger Benjamin , Renard‐Penna Raphaele 
Published: March 2018

BackgroundThe incremental value of dynamic contrast‐enhanced (DCE) imaging in localizing radiorecurrent prostate cancer is uncertain.PurposeTo assess the added‐value of DCE imaging to the combination T2‐weighted imaging (T2W)+diffusion‐weighted imaging (DWI) in detecting locally radiorecurrent prostate cancer (PCa), by radiologists with different levels of experience.Study TypeAnalytic retrospective study.PopulationIn all, 52 men with biological suspected PCa recurrence after radiotherapy were retrospectively included.Field Strength/SequenceAll men underwent prostatic MRI (1.5T or 3T), including T2W, DWI, and DCE imagings, before biopsies.AssessmentTwo junior (6 months' experience) and two senior readers (more than 3 years' experience) independently assigned a Likert score for each prostatic sextant on T2W+DW+DCE imagings, then on T2W+DW imagings, 4 weeks later.Statistical TestsThe reference standard was prostatic biopsies. For two levels of positivity of Likert score, 3/5 and 4/5, sensitivity, specificity, area under the receiver operating curve (AUC), and interreader agreement were compared.ResultsT2W+DWI+DCE and T2W+DWI imaging had similar AUC at lobe and sextant level (0.853–0.946 vs. 0.819–0.955, P from 0.071–0.534). Using a Likert score ≥4/5, T2W+DWI+DCE significantly improved the sensitivity for junior readers at the patient, lobe, and sextant level (40–80% vs. 22–66%, P < 0.0001–0.041). Sensitivity was not significantly modified with DCE imaging for senior readers (54–95% vs. 50–91%, P from 0.074–1). Specificity was not modified for all readers (50–100% vs. 50%–100%, P from 0.134–1). DCE imaging improved interreader agreement for a Likert score ≥4/5 (kappa from 0.6–0.73 vs. 0.38–0.73).Data ConclusionThe addition of DCE imaging did not significantly improve accuracy in recurrent PCa detection after radiotherapy, whatever the level of experience of the readers. However, the addition of DCE imaging slightly improved the sensitivity for less‐experienced readers and increased their diagnostic confidence.Level of Evidence: 3Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2018;48:1012–1023.
Variable flip angle 3D ultrashort echo time (UTE) T1 mapping of mouse lung: A repeatability assessment
Authors: Alamidi Daniel F. , Smailagic Amir , Bidar Abdel W. , Parker Nicole S. , Olsson Marita , Hockings Paul D. , Lagerstrand Kerstin M. , Olsson Lars E. 
Published: March 2018

BackgroundLung T1 is a potential translational biomarker of lung disease. The precision and repeatability of variable flip angle (VFA) T1 mapping using modern 3D ultrashort echo time (UTE) imaging of the whole lung needs to be established before it can be used to assess response to disease and therapy.PurposeTo evaluate the feasibility of regional lung T1 quantification with VFA 3D‐UTE and to investigate long‐ and short‐term T1 repeatability in the lungs of naive mice.Study typeProspective preclinical animal study.PopulationEight naive mice and phantoms.Field strength/Sequence3D free‐breathing radial UTE (8 μs) at 4.7T.AssessmentVFA 3D‐UTE T1 calculations were validated against T1 values measured with inversion recovery (IR) in phantoms. Lung T1 and proton density (S0) measurements of whole lung and muscle were repeated five times over 1 month in free‐breathing naive mice. Two consecutive T1 measurements were performed during one of the imaging sessions.Statistical TestsAgreement in T1 between VFA 3D‐UTE and IR in phantoms was assessed using Bland–Altman and Pearson 's correlation analysis. The T1 repeatability in mice was evaluated using coefficient of variation (CV), repeated‐measures analysis of variance (ANOVA), and paired t‐test.ResultsGood T1 agreement between the VFA 3D‐UTE and IR methods was found in phantoms. T1 in lung and muscle showed a 5% and 3% CV (1255 ± 63 msec and 1432 ± 42 msec, respectively, mean ± SD) with no changes in T1 or S0 over a month. Consecutive measurements resulted in an increase of 2% in both lung T1 and S0.Data ConclusionVFA 3D‐UTE shows promise as a reliable T1 mapping method that enables full lung coverage, high signal‐to‐noise ratio (∼25), and spatial resolution (300 μm) in freely breathing animals. The precision of the VFA 3D‐UTE method will enable better design and powering of studies.Level of Evidence: 1Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2018;48:846–852.
MR‐assisted PET motion correction in simultaneous PET/MRI studies of dementia subjects
Authors: Chen Kevin T. , Salcedo Stephanie , Chonde Daniel B. , Izquierdo‐Garcia David , Levine Michael A. , Price Julie C. , Dickerson Bradford C. , Catana Ciprian 
Published: March 2018

BackgroundSubject motion in positron emission tomography (PET) studies leads to image blurring and artifacts; simultaneously acquired magnetic resonance imaging (MRI) data provides a means for motion correction (MC) in integrated PET/MRI scanners.PurposeTo assess the effect of realistic head motion and MR‐based MC on static [18F]‐fluorodeoxyglucose (FDG) PET images in dementia patients.Study TypeObservational study.PopulationThirty dementia subjects were recruited.Field Strength/Sequence3T hybrid PET/MR scanner where EPI‐based and T1‐weighted sequences were acquired simultaneously with the PET data.AssessmentHead motion parameters estimated from high temporal resolution MR volumes were used for PET MC. The MR‐based MC method was compared to PET frame‐based MC methods in which motion parameters were estimated by coregistering 5‐minute frames before and after accounting for the attenuation‐emission mismatch. The relative changes in standardized uptake value ratios (SUVRs) between the PET volumes processed with the various MC methods, without MC, and the PET volumes with simulated motion were compared in relevant brain regions.Statistical TestsThe absolute value of the regional SUVR relative change was assessed with pairwise paired t‐tests testing at the P = 0.05 level, comparing the values obtained through different MR‐based MC processing methods as well as across different motion groups. The intraregion voxelwise variability of regional SUVRs obtained through different MR‐based MC processing methods was also assessed with pairwise paired t‐tests testing at the P = 0.05 level.ResultsMC had a greater impact on PET data quantification in subjects with larger amplitude motion (higher than 18% in the medial orbitofrontal cortex) and greater changes were generally observed for the MR‐based MC method compared to the frame‐based methods. Furthermore, a mean relative change of ∼4% was observed after MC even at the group level, suggesting the importance of routinely applying this correction. The intraregion voxelwise variability of regional SUVRs was also decreased using MR‐based MC. All comparisons were significant at the P = 0.05 level.Data ConclusionIncorporating temporally correlated MR data to account for intraframe motion has a positive impact on the FDG PET image quality and data quantification in dementia patients.Level of Evidence: 3Technical Efficacy: Stage 1J. Magn. Reson. Imaging 2018;47:1288–1296.
Consistency of Multiple Renal Functional MRI Measurements Over 18 Months
Authors: Li Lu‐Ping , Thacker Jon , Li Wei , Tan Huan , Wang Chi , Kohn Orly , Sprague Stuart , Prasad Pottumarthi 
Published: March 2018

BackgroundIdentification of patients with progressive chronic kidney disease (CKD) and those likely to respond to candidate therapeutics is urgently needed. Functional MRI measurements have shown promise. However, knowledge about the consistency of the measurements is essential to conduct longitudinal studies.Purpose/HypothesisTo investigate the consistency of repeated functional MRI measurements in healthy subjects.Study TypeProspective, longitudinal study.SubjectsSeventeen healthy subjects were examined on two different occasions, 18 months apart.Field Strength/SequenceMultiple gradient‐recalled‐echo, 2D navigator‐gated flow‐sensitive alternating inversion recovery True‐FISP and spin‐echo planar diffusion‐weighted sequences were used on a 3T scanner. Images were acquired on two different scanner configurations.AssessmentBlood oxygenation level‐dependent (BOLD) R2*, arterial spin labeling (ASL) perfusion‐derived blood flow (BF) and apparent diffusion coefficient (ADC) maps were analyzed using a custom image processing toolbox. Regions of interest (ROIs) were placed on renal cortex, medulla, and whole kidney. Multiple researchers were involved in defining the ROIs.Statistical TestsIntra‐ and intersubject coefficients of variation (CV) and Bland–Altman plots were used to measure consistency and evaluate bias in the measurements. A nonparametric Wilcoxon test was used to compare differences between two timepoints.ResultsThe intrasubject CV for R2* and ADC were 6.8% and 5.3% with small (−3.8 and 5.3%) bias, respectively, comparing baseline and 18‐month data. Intrasubject CV for renal cortex BF was higher (18.7%) compared to R2* and ADC, but comparable to prior literature values over shorter durations. It also exhibited a larger bias (−15.4%) between two timepoints and significantly lower values (P = 0.022) at 18‐month data.Data ConclusionAll three MRI parameters over 18 months, even with a scanner upgrade and involving multiple observers, showed good consistency. These results are useful for the interpretation of longitudinal data and support the use of these methods to monitor progression in patients with CKD.Level of Evidence: 1Technical Efficacy: Stage 1J. MAGN. RESON. IMAGING 2018;48:514–521.
Application of a glass fertilizer in sustainable tomato plant crops
Authors: Tamayo Aitana , de la Torre Rosa , Ruiz Oscar , Lozano Pablo , Mazo Maria Alejandra , Rubio Juan 
Published: March 2018

AbstractBACKGROUNDGlass frits with a P2O5/K2O ratio equal to 0.65 and different concentrations of SiO2 (6.5–56.0 wt%), CaO (0–5.1 wt%) and Al2O3 (0–14.6 wt%) have been prepared and analysed as potential glass fertilizers (GF).RESULTSP2O5 and K2O were leached primarily within the first 5 days but the total amount was dependent on the SiO2/Al2O3 ratio of the glass frit. Sustained P2O5 and K2O leaching for more than 40 days could be obtained if the glass frit contained more than 7% Al2O3. A final glass frit composition (29% SiO2, 5% CaO, 7% Al2O3, 30% P2O5, 25% K2O) was selected and used in an experimental tomato crop of 1 ha area, where one half was fertilized with an NPK conventional fertilizer and the other half with the GF fertilizer.CONCLUSIONAfter harvesting the tomato crops, the GF fertilizer was found to result in a higher yield than the NPK conventional fertilizer: 59980 kg and 74 360 kg for NKP and GF, respectively. The general characteristics of the harvested tomato fruits and leaves were similar in the two cases and the differences fell within statistical error. No differences in any of the soil characteristics were detected as a result of the use of GF. © 2018 Society of Chemical Industry
Ampullary adenocarcinoma: Defining predictors of survival and the impact of adjuvant therapy following surgical resection for stage I disease
Authors: Stiles Zachary E. , Behrman Stephen W. , Deneve Jeremiah L. , Glazer Evan S. , Dong Lei , Wan Jim Y. , Martin Michael G. , Dickson Paxton V. 
Published: March 2018

Background and ObjectivesOutcomes and recommendations regarding adjuvant therapy (AT) for stage I ampullary adenocarcinoma (AAC) are inadequately described. We sought to determine factors associated with survival and better define the impact of AT.MethodsThe NCDB was queried for stage I AAC patients undergoing resection. We evaluated variables influencing the administration of AT and affecting survival, including the receipt of AT.ResultsFive hundred thirty‐seven patients were identified. 1, 3, and 5‐year OS were 91.3%, 78.8%, and 67.4%, respectively. 103 received AT: 101 chemotherapy, 31 radiation, and 29 a combination of both. AT was more commonly utilized in patients with poorly differentiated and T2 tumors. Comorbid disease was inversely associated with use of AT. Age ≥65 was associated with decreased survival for stage IA and IB, while positive resection margins and sampling of <12 LNs were associated with decreased OS for stage IA and IB, respectively. After propensity matching key covariates, no significant difference in OS was observed between those receiving and not receiving AT (P = 0.449).ConclusionThis analysis revealed a modest 5‐year OS for stage I AAC. Age, positive resection margins, and evaluation of <12 LNs negatively influenced OS and AT did not convey a survival benefit.
The Influence of Substituents in the 3‐Position on the Polymerization of Metaphenylenes
Authors: Leysen Pieter , Mannaerts Astrid , Koeckelberghs Guy 
Published: March 2018

AbstractIn this manuscript, the influence of the position of the alkoxy‐substituents on the polymerization of poly(phenylenes) is investigated. For this purpose, 3‐alkoxy‐m‐phenylene is polymerized using the Kumada catalyst transfer condensative polymerization. Three different catalyst systems are tried, which all resulted in polymer, but with a high dispersity. Additional experiments show that the polymerization proceeds via a noncontrolled chain growth mechanism.
An optimization problem for the first eigenvalue of the ‐fractional Laplacian
Authors: Del Pezzo Leandro , Fernández Bonder Julián , López Ríos Luis 
Published: March 2018

AbstractIn this paper we analyze an eigenvalue problem related to the nonlocal p‐Laplace operator plus a potential. After reviewing some elementary properties of the first eigenvalue of these operators (existence, positivity of associated eigenfunctions, simplicity and isolation) we investigate the dependence of the first eigenvalue on the potential function and establish the existence of some optimal potentials in some admissible classes.
Modeling of the unsteady flow through a channel with an artificial outflow condition by the Navier–Stokes variational inequality
Authors: Kračmar Stanislav , Neustupa Jiří 
Published: March 2018

AbstractWe prove the global in time existence of a weak solution to the variational inequality of the Navier–Stokes type, simulating the unsteady flow of a viscous fluid through the channel, with the so‐called “do nothing” boundary condition on the outflow. The condition that the solution lies in a certain given, however arbitrarily large, convex set and the use of the variational inequality enables us to derive an energy‐type estimate of the solution. We also discuss the use of a series of other possible outflow “do nothing” boundary conditions.
t‐Butyl‐Oxycarbonylated Diamines as Building Blocks for Isocyanate‐Free Polyurethane/Urea Dispersions and Coatings
Authors: Ma Shuang , Zhang Huiyi , Sablong Rafaël J. , Koning Cor E. , van Benthem Rolf A. T. M. 
Published: March 2018

Abstractt‐Butyl‐oxycarbonylated diamines (“di‐Boc‐carbamates”) are investigated as dicarbamate monomers for diamine/dicarbamate polymerizations. Polyureas (PUs) and polyurethanes (PURs) with high molecular weights are prepared from stoichiometric polymerizations of diamines or diols with N‐N′‐di‐t‐butyl‐oxycarbonyl isophorone diamine (DiBoc‐IPDC) using KOt‐Bu as a catalyst, while gelation is observed when an excess of DiBoc‐IPDC is used with respect to the diamines or diols. Stable dispersions are obtained from PUs and PURs with 3,3′‐diamino‐N‐methyldipropylamine (DMDPA) as internal dispersing agent. The corresponding PU‐based coatings exhibit superior mechanical properties and solvent resistances compared to the polyurethane urea coatings synthesized from diols, DiBoc‐IPDC, and DMDPA.
Automatically Programmable Shape‐Memory Polymers Based on Asymmetric Swelling of Bilayer Structures
Authors: Tang Junkun , Zhou Yan , Wan Liqiang , Huang Farong 
Published: March 2018

AbstractShape‐memory polymers (SMPs) possess the capability to change shapes upon stimulation; however, the programming process that determines the temporary shape cannot proceed without external manipulation, which may greatly affect the shape complexity, accuracy, and reproducibility. Here, an automatically programmable SMP (AP‐SMP) based on asymmetric swelling of bilayer SMP structures is demonstrated without external manipulation. In the automatic programming process, the AP‐SMP can be deformed by the swelling of its hydrophilic hinge film in warm water to a temporary shape, which could be fixed by the glass transition of the two SMP films through cooling and drying in air. Owing to the unique ability, many complex shapes can be easily customized through diverse design strategies. Moreover, the AP‐SMPs can reversibly transform between the permanent and temporary shapes, and both shapes are free‐standing in normal conditions. The automatic programming of AP‐SMPs may greatly expand the potential application range of SMPs.
A multi‐band rectifier with modified hybrid junction for RF energy harvesting
Authors: Li Zihong , Zeng Miaowang , Tan Hong‐Zhou 
Published: March 2018

AbstractThis article presents a novel multi‐band rectifier utilizing modified hybrid structure for radio frequency (RF) energy harvesting. The proposed multi‐band rectifier consists of a modified hybrid junction and three rectifying branches. The rectifying branches are placed inside the modified hybrid to reduce the layout size. The proposed multi‐band rectifier is designed for GSM‐1800, UMTS‐2100, and Wi‐Fi bands. Measured peak efficiency of the proposed rectifier reaches 61.7% at 9 dBm input power level. The results show a good overall performance on operation bands, efficiency, output voltage, and layout size. The proposed rectifier can be used for various RF energy harvesting applications, especially in the multi‐source condition.
Temperature‐dependent characteristics of a RTD‐based microwave push‐push oscillator
Authors: Lee Kiwon , Jeong Yongsik 
Published: March 2018

AbstractIn this letter, the temperature dependence of a microwave push–push oscillator based on a resonant tunneling diode (RTD) has been investigated from 30°C to 80°C. An output power characteristic curve of the second‐harmonic RTD oscillator has been shifted to the higher bias voltages as temperature increases. An oscillation frequency shift of ΔfOSC has been obtained to be –9.8 MHz/K which is equivalent to the ΔfOSC of –4.9 MHz/K at the fundamental oscillation frequency of 14.45 GHz. To authors’ knowledge, this is the first report on the temperature dependent characteristics of the second‐harmonic push–push RTD oscillator.
Pseudo‐color enhancement and its segmentation for femtosecond laser spot image
Authors: Wang Fu‐Bin , Wu Chen , Liu Yang , Feng Ding , Tu Paul 
Published: March 2018

AbstractWhen using femtosecond laser processing silicon wafer, arises laser spot along with the plasma diffraction. Comparatively studied the spot images of silicon wafer which was in three processing movement states as follows: towards the left, stop, towards the right, found that the three dimensional Gauss mean ablation energy of spot image almost kept the same, this provides experimental support for femtosecond laser feedback processing based on Gauss energy of spot image. Then the following image enhancement strategies are proposed: pseudo color transformation for spot image, color decomposition in RGB space and image superposition of G component, and the quality of the spot image is improved. In addition, adopted the method of Particle Swarm Optimization (PSO) or K‐means respectively, analyzed the segmentation effect for spot image: through traversal compares the gray value of image pixel and fitness function, realized the spot image segmentation with PSO, and the clustering and segmentation for data cluster of image pixel was realized by K‐means. Finally, overcome the shortcomings of PSO and K‐means, the ideal segmentation for spot target image is realized by combining the two methods.
SIW‐based cavity‐backed self‐diplexing antenna with plus‐shaped slot
Authors: Nandi Sourav , Mohan Akhilesh 
Published: March 2018

AbstractA substrate integrated waveguide (SIW)‐based planar cavity‐backed self‐diplexing antenna, designed for X‐band applications, is presented in this article. The proposed antenna is fed by two orthogonal 50 Ω microstrip lines. Two orthogonal rectangular slots, combination of which makes a plus‐shaped slot, of different lengths are etched on the top of the SIW cavity. Due to the unequal arm lengths of the plus‐shaped slot, the antenna radiates at two distinct frequencies. An isolation of better than 20 dB is achieved between the two ports and hence, the proposed antenna exhibits self‐diplexing characteristics. The antenna offers a gain of 5.7 dBi and 5.94 dBi at 8.55 GHz and 9.77 GHz, respectively.
Low profile CPW fed slotted planar inverted cone ultra‐wide band antenna for WBAN applications
Authors: Nadeem Muhammad , Khan Ali Nawaz , Ali Khan Asim , Azim Tayyab 
Published: March 2018

AbstractThis letter presents the design and analysis of a smart and low profile Ultra‐Wideband Slotted Planar Inverted Cone Antenna. The proposed slotted PICA has low profile (0.4 λ mm2 × 0.4 λ mm2) as compared to other existing designs and its operational bandwidth is from 3 GHz to 18 GHz. The simulated and measured results concur with acceptable return loss of better than 10 dB throughout the operational bandwidth. The radiation pattern of the antenna is omnidirectional and it has maximum Gain of 3.2 dB when placed close to human body, making it compatible for WBAN applications.
Fiber‐based measurement of temporal intensity and phase profiles of an optical telecommunication pulse through self‐phase modulation
Authors: Baudin Killian , Audo Frédéric , Finot Christophe 
Published: March 2018

AbstractWe propose and experimentally validate an all‐fiber based approach to characterize the phase and intensity profiles of optical pulses. Based on three optical spectra affected by different levels of self‐phase modulation, we were able to reconstruct the temporal details of pulses typical of optical telecommunications.
Leaf‐shaped CPW‐fed UWB antenna with triple notch bands for ground penetrating radar applications
Authors: Kundu Surajit , Jana Sanjay Kumar 
Published: March 2018

AbstractA compact (38.31 mm × 34.52 mm × 0.8 mm) leaf shaped CPW fed ultra‐wideband antenna is proposed. The antenna gives wide impedance bandwidth from 2.58 GHz to 11.62 GHz with sharp triple notch bands (3.28 GHz–3.82 GHz, 5.12 GHz–5.4 GHz, and 5.7 GHz–6 GHz) to eliminate interference from co‐existing IEEE 802.16 WiMAX (3.3 GHz–3.8 GHz), IEEE 802.11y (3.65 GHz–3.69 GHz), IEEE 802.11a WLAN (5.15 GHz–5.35 GHz and 5.725 GHz–5.825 GHz), and IEEE 802.11p DSRC (5.85 GHz–5.925 GHz) bands. The antenna provides minimal gain variation (2–5 dBi), flat group delay response and non‐varying transfer function with high average efficiency of 88% in the pass band. Significant drop in gain and efficiency, nonlinearity in transfer function, and high variation in group delay are observed at notch bands. Antenna VSWR, and efficiency are measured in close proximity of sand, wood, and glass. Satisfactory results ensure its ability to work as Ground penetrating radar antenna.