bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polarization microscopy as a tool for quantitative evaluation of collagen using picrosirius red in different stages of CKD in cats
Authors: Morais G. B. , Viana D. A. , Silva F. M. O. , Xavier Júnior F. A. F. , Farias K. M. , Pessoa C. D'Ó , Silveira J. A. M. , Alves A. P. N. N. , Mota M. R. L. , Silva F. D. O. , Sampaio C. M. S. , Verdugo J. M. G. , Evangelista J. S. A. M. 
Published: January 2017

AbstractChronic kidney disease (CKD) is a relevant disease in feline clinic. The tubulointerstitial damage, with collagen deposition and fibrosis, is an important result of this process. The aim of this study was to quantify and correlate the deposition of collagen and severity of interstitial fibrosis (IF) in the kidney from cats in different stages of CKD. Kidney fragments from 10 adult cats with CKD were analyzed and stained by Masson's trichrome (MT) and Picrosirius red (PSR) for circular polarized microscopy. Random quantitative analysis was performed on MT sections to classify the degree of IF, per field area, with and without circular polarization. Statistics correlations were performed by Spearman's (ρ; p < .05). There was a significant correlation of IF quantification with the area of interstitial collagen deposition by polarized PSR (PSRp) (r = .7939, p = .0098) and nonpolarized PSR (PSRn) (r = .7781, p = .0080). There was a positive correlation of serum creatinine (sCr) at different stages of CKD with PSRp (r = .7939, p = .0098), PSRn (r = .8667, p = .0027) and MT (r = .7818, p = .0117). Correlations between the percentage of quantified area was also positive from PSRp to PSRn (r = .9030, p = .0009) and PSRp to MT (r = .7939, p = .0098). The PSRN was also correlated with MT (r = .9273, p = .0001). The correlation with IF and sCr follows the disease evolution and the quantification of collagen by PSR is an excellent tool for analyzing the disease severity at different stages.
Finite 2‐Distance Transitive Graphs
Authors: Corr Brian P. , Jin Wei , Schneider Csaba 
Published: January 2017

AbstractA noncomplete graph Γ is said to be (G, 2)‐distance transitive if G is a subgroup of the automorphism group of Γ that is transitive on the vertex set of Γ, and for any vertex u of Γ, the stabilizer is transitive on the sets of vertices at distances 1 and 2 from u. This article investigates the family of (G, 2)‐distance transitive graphs that are not (G, 2)‐arc transitive. Our main result is the classification of such graphs of valency not greater than 5. We also prove several results about (G, 2)‐distance transitive, but not (G, 2)‐arc transitive graphs of girth 4.
Specific patterns of neuronal loss in the pulvinar nucleus in dementia with lewy bodies
Authors: Erskine Daniel , Thomas Alan J. , Attems Johannes , Taylor John‐Paul , McKeith Ian G. , Morris Christopher M. , Khundakar Ahmad A. 
Published: January 2017

ABSTRACTBackground: Complex visual hallucinations occur in 70%‐80% of dementia with Lewy bodies patients and significantly affect well‐being. Despite the prevalence of visual hallucinations in dementia with Lewy bodies, the neuropathological basis of this phenomenon is poorly understood. The pulvinar nucleus of the thalamus has not previously been neuropathologically examined, but has been linked to visual hallucinations in dementia with Lewy bodies. The objective of this study was to investigate whether neuropathological or morphometric changes occur in the pulvinar nucleus in dementia with Lewy bodies cases that may contribute to visual hallucinations.Methods: Postmortem pulvinar tissue was acquired from 8 individuals with dementia with Lewy bodies, 8 with Alzheimer's disease, and 8 control cases and was analyzed using stereological and quantitative neuropathological techniques.Results: Lewy body pathology was present throughout the pulvinar in dementia with Lewy bodies but was most severe in the medial pulvinar. Neuronal loss was found in the lateral pulvinar in dementia with Lewy bodies and Alzheimer's disease but was more severe in dementia with Lewy bodies.Conclusions: The pulvinar has an important role in visual attention, visual target selection and affective visual perception. These functions are thought to be deficient in dementia with Lewy bodies and may contribute a vulnerability to visual hallucinations. Therefore, this study has demonstrated neuropathological changes that may promote the manifestation of visual hallucinations in dementia with Lewy bodies. © 2017 International Parkinson and Movement Disorder Society
Consideration of documentary records in the Annals of the Choson Dynasty for the frequency analysis of rainfall in Seoul, Korea
Authors: Park Minkyu , Yoo Chulsang , Jun Changhyun 
Published: January 2017

ABSTRACTIn this study, flood records in the Annals of the Choson Dynasty (1392–1910) were considered for the frequency analysis of rainfall in Seoul, Korea. The old Korean rain gauge (Chukwooki) data (1777–1907) were also used to evaluate major flood records in the Annals of the Choson Dynasty. The design rainfalls were estimated using the binomial censored data maximum likelihood estimator. The results can be summarized as follows. (1) The frequency analysis was done for 24 h rainfall amounts as this was assumed to represent the three different rainfall records well: the documentary records in the Annals of the Choson Dynasty, the Chukwooki data and the modern data. Also, given the possible uncertainty level of the classification results of the documentary records, only 19 catastrophic events (the highest level of flood) were considered in the frequency analysis. The threshold value was decided to be 388 mm by comparing the documentary records with the Chukwooki data. (2) The sensitivity analysis shows that the effects of the threshold value, the number of catastrophic records, and the accuracy level of the flood records in the Annals of the Choson Dynasty on the frequency analysis results are very limited. That is, the length of the flood records in the Annals of the Choson Dynasty was found to be long enough to overcome the possible uncertainty of the flood records. (3) The design rainfalls estimated by taking into account the flood records in the Annals of the Choson Dynasty were found to be very similar to those for the modern data. However, the confidence intervals estimated by considering all the records available were found to be just one third of those of the modern data.
Optimizing dual‐energy x‐ray parameters for the ExacTrac clinical stereoscopic imaging system to enhance soft‐tissue imaging
Authors: Bowman Wesley A. , Robar James L. , Sattarivand Mike 
Published: January 2017

PurposeStereoscopic x‐ray image guided radiotherapy for lung tumors is often hindered by bone overlap and limited soft‐tissue contrast. This study aims to evaluate the feasibility of dual‐energy imaging techniques and to optimize parameters of the ExacTrac stereoscopic imaging system to enhance soft‐tissue imaging for application to lung stereotactic body radiation therapy.MethodsSimulated spectra and a physical lung phantom were used to optimize filter material, thickness, tube potentials, and weighting factors to obtain bone subtracted dual‐energy images. Spektr simulations were used to identify material in the atomic number range (3–83) based on a metric defined to separate spectra of high and low‐energies. Both energies used the same filter due to time constraints of imaging in the presence of respiratory motion. The lung phantom contained bone, soft tissue, and tumor mimicking materials, and it was imaged with a filter thickness in the range of (0–0.7) mm and a kVp range of (60–80) for low energy and (120,140) for high energy. Optimal dual‐energy weighting factors were obtained when the bone to soft‐tissue contrast‐to‐noise ratio (CNR) was minimized. Optimal filter thickness and tube potential were achieved by maximizing tumor‐to‐background CNR. Using the optimized parameters, dual‐energy images of an anthropomorphic Rando phantom with a spherical tumor mimicking material inserted in his lung were acquired and evaluated for bone subtraction and tumor contrast. Imaging dose was measured using the dual‐energy technique with and without beam filtration and matched to that of a clinical conventional single energy technique.ResultsTin was the material of choice for beam filtering providing the best energy separation, non‐toxicity, and non‐reactiveness. The best soft‐tissue‐weighted image in the lung phantom was obtained using 0.2 mm tin and (140, 60) kVp pair. Dual‐energy images of the Rando phantom with the tin filter had noticeable improvement in bone elimination, tumor contrast, and noise content when compared to dual‐energy imaging with no filtration. The surface dose was 0.52 mGy per each stereoscopic view for both clinical single energy technique and the dual‐energy technique in both cases of with and without the tin filter.ConclusionsDual‐energy soft‐tissue imaging is feasible without additional imaging dose using the ExacTrac stereoscopic imaging system with optimized acquisition parameters and no beam filtration. Addition of a single tin filter for both the high and low energies has noticeable improvements on dual‐energy imaging with optimized parameters. Clinical implementation of a dual‐energy technique on ExacTrac stereoscopic imaging could improve lung tumor visibility.
Scatter correction using a primary modulator on a clinical angiography C‐arm CT system
Authors: Bier Bastian , Berger Martin , Maier Andreas , Kachelrieß Marc , Ritschl Ludwig , Müller Kerstin , Choi Jang‐Hwan , Fahrig Rebecca 
Published: January 2017

PurposeCone beam computed tomography (CBCT) suffers from a large amount of scatter, resulting in severe scatter artifacts in the reconstructions. Recently, a new scatter correction approach, called improved primary modulator scatter estimation (iPMSE), was introduced. That approach utilizes a primary modulator that is inserted between the X‐ray source and the object. This modulation enables estimation of the scatter in the projection domain by optimizing an objective function with respect to the scatter estimate. Up to now the approach has not been implemented on a clinical angiography C‐arm CT system.MethodsIn our work, the iPMSE method is transferred to a clinical C‐arm CBCT. Additional processing steps are added in order to compensate for the C‐arm scanner motion and the automatic X‐ray tube current modulation. These challenges were overcome by establishing a reference modulator database and a block‐matching algorithm. Experiments with phantom and experimental in vivo data were performed to evaluate the method.ResultsWe show that scatter correction using primary modulation is possible on a clinical C‐arm CBCT. Scatter artifacts in the reconstructions are reduced with the newly extended method. Compared to a scan with a narrow collimation, our approach showed superior results with an improvement of the contrast and the contrast‐to‐noise ratio for the phantom experiments. In vivo data are evaluated by comparing the results with a scan with a narrow collimation and with a constant scatter correction approach.ConclusionsScatter correction using primary modulation is possible on a clinical CBCT by compensating for the scanner motion and the tube current modulation. Scatter artifacts could be reduced in the reconstructions of phantom scans and in experimental in vivo data.
Statistical image‐domain multimaterial decomposition for dual‐energy CT
Authors: Xue Yi , Ruan Ruoshui , Hu Xiuhua , Kuang Yu , Wang Jing , Long Yong , Niu Tianye 
Published: January 2017

PurposeDual‐energy CT (DECT) enhances tissue characterization because of its basis material decomposition capability. In addition to conventional two‐material decomposition from DECT measurements, multimaterial decomposition (MMD) is required in many clinical applications. To solve the ill‐posed problem of reconstructing multi‐material images from dual‐energy measurements, additional constraints are incorporated into the formulation, including volume and mass conservation and the assumptions that there are at most three materials in each pixel and various material types among pixels. The recently proposed flexible image‐domain MMD method decomposes pixels sequentially into multiple basis materials using a direct inversion scheme which leads to magnified noise in the material images. In this paper, we propose a statistical image‐domain MMD method for DECT to suppress the noise.MethodsThe proposed method applies penalized weighted least‐square (PWLS) reconstruction with a negative log‐likelihood term and edge‐preserving regularization for each material. The statistical weight is determined by a data‐based method accounting for the noise variance of high‐ and low‐energy CT images. We apply the optimization transfer principles to design a serial of pixel‐wise separable quadratic surrogates (PWSQS) functions which monotonically decrease the cost function. The separability in each pixel enables the simultaneous update of all pixels.ResultsThe proposed method is evaluated on a digital phantom, Catphan©600 phantom and three patients (pelvis, head, and thigh). We also implement the direct inversion and low‐pass filtration methods for a comparison purpose. Compared with the direct inversion method, the proposed method reduces noise standard deviation (STD) in soft tissue by 95.35% in the digital phantom study, by 88.01% in the Catphan©600 phantom study, by 92.45% in the pelvis patient study, by 60.21% in the head patient study, and by 81.22% in the thigh patient study, respectively. The overall volume fraction accuracy is improved by around 6.85%. Compared with the low‐pass filtration method, the root‐mean‐square percentage error (RMSE(%)) of electron densities in the Catphan©600 phantom is decreased by 20.89%. As modulation transfer function (MTF) magnitude decreased to 50%, the proposed method increases the spatial resolution by an overall factor of 1.64 on the digital phantom, and 2.16 on the Catphan©600 phantom. The overall volume fraction accuracy is increased by 6.15%.ConclusionsWe proposed a statistical image‐domain MMD method using DECT measurements. The method successfully suppresses the magnified noise while faithfully retaining the quantification accuracy and anatomical structure in the decomposed material images. The proposed method is practical and promising for advanced clinical applications using DECT imaging.
Towards a neurochemical profile of the amygdala using short‐TE 1H magnetic resonance spectroscopy at 3 T
Authors: Schubert Florian , Kühn Simone , Gallinat Jürgen , Mekle Ralf , Ittermann Bernd 
Published: January 2017

The amygdala plays a key role in emotional learning and in the processing of emotions. As disturbed amygdala function has been linked to several psychiatric conditions, a knowledge of its biochemistry, especially neurotransmitter levels, is highly desirable. The spin echo full intensity acquired localized (SPECIAL) sequence, together with a transmit/receive coil, was used to perform very short‐TE magnetic resonance spectroscopy at 3 T to determine the neurochemical profile in a spectroscopic voxel containing the amygdala in 21 healthy adult subjects. For spectral analysis, advanced data processing was applied in combination with a macromolecule baseline measured in the anterior cingulate for spectral fitting. The concentrations of total N‐acetylaspartate, total creatine, total choline, myo‐inositol and, for the first time, glutamate were quantified with high reliability (uncertainties far below 10%). For these metabolites, the inter‐individual variability, reflected by the relative standard deviations for the cohort studied, varied between 12% (glutamate) and 22% (myo‐inositol). Glutamine and glutathione could also be determined, albeit with lower precision. Retest on four subjects showed good reproducibility. The devised method allows the determination of metabolite concentrations in the amygdala voxel, including glutamate, provides an estimation of glutamine and glutathione, and may help in the study of disturbed amygdala metabolism in pathologies such as anxiety disorder, autism and major depression.
Validation of clinic weights from electronic health records against standardized weight measurements in weight loss trials
Authors: Xiao Lan , Lv Nan , Rosas Lisa G. , Au David , Ma Jun 
Published: January 2017

ObjectiveTo validate clinic weights in electronic health records against researcher‐measured weights for outcome assessment in weight loss trials.MethodsClinic and researcher‐measured weights from a published trial (BE WELL) were compared using Lin's concordance correlation coefficient, Bland and Altman's limits of agreement, and polynomial regression model. Changes in clinic and researcher‐measured weights in BE WELL and another trial, E‐LITE, were analyzed using growth curve modeling.ResultsAmong BE WELL (n = 330) and E‐LITE (n = 241) participants, 96% and 90% had clinic weights (mean [SD] of 5.8 [6.1] and 3.7 [3.9] records) over 12 and 15 months of follow‐up, respectively. The concordance correlation coefficient was 0.99, and limits of agreement plots showed no pattern between or within treatment groups, suggesting overall good agreement between researcher‐measured and nearest‐in‐time clinic weights up to 3 months. The 95% confidence intervals for predicted percent differences fell within ±3% for clinic weights within 3 months of the researcher‐measured weights. Furthermore, the growth curve slopes for clinic and researcher‐measured weights by treatment group did not differ significantly, suggesting similar inferences about treatment effects over time, in both trials.ConclusionsCompared with researcher‐measured weights, close‐in‐time clinic weights showed high agreement and inference validity. Clinic weights could be a valid pragmatic outcome measure in weight loss studies.
Model of a polymer chain twisted inside a statistical segment. Poly(3‐hexylthiophene) in chloroform solutions
Authors: Bushin Stanislav V , Bezrukova Marina A , Koeckelberghs Guy , Persoons André , Yakimansky Alexander V 
Published: January 2017

AbstractA set of hydrodynamic methods in extremely dilute solutions (determination of intrinsic viscosity [η], translational diffusion D and flotation in a centrifugal field s) was used in the studies of conformational properties, dimensions and equilibrium rigidity of individual molecules of a series of samples of poly(3‐hexylthiophene). Absolute molecular masses MsD were determined. The Mark–Kuhn–Houwink equations for the range of MsD from 2240 to 15 300 g mol−1 are given. For the first time, an analysis of conformational properties and equilibrium flexibility of poly(3‐hexylthiophene) molecules was carried out using the model of a statistical segment containing a twisted polymer chain. © 2017 Society of Chemical Industry
Responsiveness of the bridge maneuvers in subjects with symptomatic lumbar spondylolisthesis: A prospective cohort study
Authors: Vanti Carla , Ferrari Silvano , Berjano Pedro , Villafañe Jorge Hugo , Monticone Marco 
Published: January 2017

AbstractBackground and PurposeTo date no study was made on the responsiveness of Bridge tests (BTs) in subjects with low back pain and spondylolisthesis (SPL) submitted to a physical therapy program. The objective of this study is to examine the responsiveness of the BTs in subjects with symptomatic lumbar SPL.MethodsOne hundred twenty patients with symptomatic SPL received physical therapy treatments for a number of sessions depending on the individual patient's needs. Each session included supervised exercises and the teaching of home exercises aiming to improve the lumbar stability, for about 1 hr in total. At the beginning and immediately after the last session of treatment, participants completed the Oswestry Disability Index – Italian version and the Pain Numerical Rating Scale, and performed the supine bridging (SBT) and the prone bridging (PBT). The global perception of effectiveness was measured with a seven‐point Likert scale Global Perceived Effect questionnaire.ResultsThe mean post‐treatment change score (95% confidence interval [CI]) was 18.2 s (14.5; 21.9) for the PBT and 43.9 s (35.1; 52.8) for the SBT, all p < .001. The area under the receiver operating characteristic curve for the PBT was 0.83 (95% CI 0.74–0.91) and for the SBT was 0.703 (95% CI 0.61–0.80). The optimal cutoff points were 19.5 s for the PBT and 62.5 s for the SBT. Logistic regression revealed that PBT (odds ratio = 0.952) was associated with the type of SPL. The final regression model explained 36.4% (R2 = 0.36; p = .001) of the variability.DiscussionBridge maneuvers proved to be responsive, because their results were significantly related to pain and disability changes. BTs may be suggested to detect clinical changes after physical therapy treatment in symptomatic SPL. Copyright © 2017 John Wiley & Sons, Ltd.
IQC‐based robustness analysis of discrete‐time linear time‐varying systems
Authors: Fry J. Micah , Farhood Mazen , Seiler Peter 
Published: January 2017

SummaryThe paper investigates the robust stability and performance of uncertain linear time‐varying (LTV) systems using an integral quadratic constraint (IQC) based analysis approach. Specifically, previous theoretical work on IQC‐based robustness analysis of linear time‐invariant (LTI) systems is extended to discrete‐time LTV systems. In the case of a general LTV nominal system, the analysis solution is provided in terms of an infinite‐dimensional convex optimization problem. This optimization problem reduces into a finite‐dimensional semidefinite program when the nominal system in question is finite horizon, periodic, or, more generally, eventually periodic. Finally, the results are applied to an unmanned aircraft control system executing an aggressive maneuver, where the developed techniques are used to find the region in which the aircraft is guaranteed to reside at the end of its planned trajectory. Copyright © 2017 John Wiley & Sons, Ltd.
Agraulos ceticephalusand other Cambrian trilobites in the subfamily Agraulinae from Bohemia, Newfoundland and Wales
Authors: Fletcher Terence P. 
Published: January 2017

AbstractThe Cambrian trilobiteAgraulos ceticephalusBarrande, first described from Bohemia, is the type species for the genus and subfamily Agraulinae. That subfamily is here regarded as a ptychoparioid grouping in the family Solenopleuridae, characterized by prominently punctate cephala. In Bohemia, it occurs with, and is related to, specimens of the genus SkreiaspisRůžička, differing mainly in their glabellar shapes and cephalic borders. More‐complete descriptions of their type species are based largely on undistorted museum topotypes and supplementary specimens ofceticephaluscollected from Avalonian Newfoundland and Wales. With such information and the use of Photoshop, a reinterpretation of the original tectonically‐distorted syntypes of ‘A. longicephalus’ from Wales indicates that those specimens cannot be differentiated fromceticephalus. Consequently, Hicks’ species may be regarded as a junior synonym. Additional information derived from recent Welsh collections concerns the hypostome–rostral plate relationship ofceticephalusand the recognition of a ventral plate lying beneath the rostral plate. Non‐syntype Welsh material, subsequently assigned to ‘longicephalus’, includes specimens ofA. lewisisp. nov. with a prominent occipital spine, relatively long genal spines and upstanding thoracic axial spines. Other species ofAgraulosoccur in Newfoundland, viz.,affinis,socialis, ‘sp. nov. 1’ and ‘sp. nov. 2’, marked by differences in their anterior cephalic borders, occipital rings and ornamented thoracic axes. Two species ofSkreiaspis, viz.,punctatissimussp. nov and ‘S. sp. nov. 1’ are recognized in the Newfoundland succession along with two other agraulines,Skehanos quadrangularisWhitfield and ‘Agraulinae gen. nov.’ To demonstrate the significant differences between the biometrics of the external surfaces and their inner parietal moulds/casts, and those of meraspid–holaspid cranidial growth stages between 0.10 and 2.9 cm sagittal length, a suite ofA. socialiscranidia intermixed with some other Newfoundland agraulines of comparable size is illustrated.