bluuebunny/crossref_metadata_2025_split huggingface dataset:
A prototype spatial–spectral CT system for material decomposition with energy‐integrating detectors
Authors: Tivnan Matthew , Wang Wenying , Stayman J. Webster 
Published: May 2021

PurposeSpectral CT has great potential for a variety of clinical applications due to improved tissue and material discrimination over conventional single‐energy CT. Many clinical and preclinical spectral CT systems have two spectral channels enabling dual‐energy CT. Strategies include split filtration, dual‐layer detectors, photon‐counting detectors, and kVp switching. The motivation for this work is the development of an x‐ray source spectral modulation device with three or more spectral channels to enable high‐sensitivity multi‐material decomposition with energy‐integrating detectors.Materials and MethodsWe present spatial–spectral filters which are a new x‐ray source modulation technology with the potential for additional channel diversity. The filtering device consists of an array of K‐edge materials which divide the x‐ray beam into spectrally varied beamlets. This design allows for an arbitrary number of spectral channels—trading off spatial and spectral information. We use a one‐step model‐based material decomposition (MBMD) algorithm to iteratively estimate material density images directly from the spatial–spectral CT data. In this work, we present a prototype spatial–spectral filter integrated with an x‐ray CT test bench. The filter is composed of an array of tin, erbium, tantalum, and lead filter tiles which spatially modulate the system spectral sensitivity pattern. In a simulation study, we investigate the particular problem of mis‐calibration between the data acquisition and the reconstruction model. With an understanding of the required model accuracy, we present a spectral calibration method to estimate the critical model parameters. To demonstrate feasibility of the spatial–spectral filter with a calibrated beamlet model, we collected a spatial–spectral CT scan of a multicontrast‐enhanced phantom containing water, iodine, and gadolinium solutions.ResultsWith simulations, we show that material decomposition is possible with spatial–spectral‐filtered CT data, and we demonstrate the importance of a well‐calibrated physical model. We find a 50% increase in error for focal spot model mismatch of 0.27mm and gap width model mismatch of 16 mμ. With physical results, we demonstrate that the calibrated system model is in close agreement with the measured data, and that the reconstructed material density images match the ground truth concentrations for the multicontrast phantom. Empirical results indicate gadolinium density estimation had an error of 17‐58% mostly due to a systematic constant bias of 0.30–0.60 mg/ml. Water density estimates are within 1% and iodine estimates are within 10% of ground truth.ConclusionThese preliminary results demonstrate the potential of spatial–spectral filters to enable multicontrast imaging. Moreover, this device is compatible with energy‐integrating detectors and so provides a feasible modification to enable spectral CT imaging with existing single‐energy systems.
High spectral and spatial resolution MRI of prostate cancer: a pilot study
Authors: Medved Milica , Chatterjee Aritrick , Devaraj Ajit , Harmath Carla , Lee Grace , Yousuf Ambereen , Antic Tatjana , Oto Aytekin , Karczmar Gregory S. 
Published: May 2021

PurposeHigh spectral and spatial resolution (HiSS) MRI is a spectroscopic imaging method focusing on water and fat resonances that has good diagnostic utility in breast imaging. The purpose of this work was to assess the feasibility and potential utility of HiSS MRI for the diagnosis of prostate cancer.MethodsHiSS MRI was acquired at 3 T from six patients who underwent prostatectomy, yielding a train of 127 phase‐coherent gradient echo (GRE) images. In the temporal domain, changes in voxel intensity were analyzed and linear (R) and quadratic (R1, R2) quantifiers of signal logarithm decay were calculated. In the spectral domain, three signal scaling‐independent parameters were calculated: water resonance peak width (PW), relative peak asymmetry (PRA), and relative peak distortion from ideal Lorentzian shape (PRD). Seven cancer and five normal tissue regions of interest were identified in correlation with pathology and compared.ResultsHiSS‐derived quantifiers, except R2, showed high reproducibility (coefficients of variation, 5%‐14%). Spectral domain quantifiers performed better than temporal domain quantifiers, with receiver operator characteristic areas under the curve ranging from of 0.83 to 0.91. For temporal domain parameters, the range was 0.74 to 0.91. Low absolute values of the coefficients of correlation between monoexponential decay markers (R, PW) and resonance shape markers (PRA, PRD) were observed (range, 0.23‐0.38).ConclusionThe feasibility and potential diagnostic utility of HiSS MRI in the prostate at 3 T without an endorectal coil was confirmed. Weak correlation between well‐performing markers indicates that complementary information could be leveraged to further improve diagnostic accuracy.
Automatic determination of the regularization weighting for wavelet‐based compressed sensing MRI reconstructions
Authors: Varela‐Mattatall Gabriel , Baron Corey A. , Menon Ravi S. 
Published: May 2021

PurposeTo present a method that automatically, rapidly, and in a noniterative manner determines the regularization weighting for wavelet‐based compressed sensing reconstructions. This method determines level‐specific regularization weighting factors from the wavelet transform of the image obtained from zero‐filling in k‐space.MethodsWe compare reconstruction results obtained by our method,, to the ones obtained by the L‐curve,, and the minimum NMSE,. The comparisons are done using in vivo data; then, simulations are used to analyze the impact of undersampling and noise. We use NMSE, Pearson’s correlation coefficient, high‐frequency error norm, and structural similarity as reconstruction quality indices.ResultsOur method,, provides improved reconstructed image quality to that obtained byregardless of undersampling or SNR and comparable quality toat high SNR. The method determines the regularization weighting prospectively with negligible computational time.ConclusionOur main finding is an automatic, fast, noniterative, and robust procedure to determine the regularization weighting. The impact of this method is to enable prospective and tuning‐free wavelet‐based compressed sensing reconstructions.
A phase Ib/IIa, open‐label, multiple ascending‐dose trial of domagrozumab in fukutin‐related protein limb‐girdle muscular dystrophy
Authors: Leung Doris G. , Bocchieri Alex E. , Ahlawat Shivani , Jacobs Michael A. , Parekh Vishwa S. , Braverman Vladimir , Summerton Katherine , Mansour Jennifer , Stinson Nikia , Bibat Genila , Morris Carl , Marraffino Shannon , Wagner Kathryn R. 
Published: May 2021

AbstractIntroduction/AimsIn this study we report the results of a phase Ib/IIa, open‐label, multiple ascending‐dose trial of domagrozumab, a myostatin inhibitor, in patients with fukutin‐related protein (FKRP)‐associated limb‐girdle muscular dystrophy.MethodsNineteen patients were enrolled and assigned to one of three dosing arms (5, 20, or 40 mg/kg every 4 weeks). After 32 weeks of treatment, participants receiving the lowest dose were switched to the highest dose (40 mg/kg) for an additional 32 weeks. An extension study was also conducted. The primary endpoints were safety and tolerability. Secondary endpoints included muscle strength, timed function testing, pulmonary function, lean body mass, pharmacokinetics, and pharmacodynamics. As an exploratory outcome, muscle fat fractions were derived from whole‐body magnetic resonance images.ResultsSerum concentrations of domagrozumab increased in a dose‐dependent manner and modest levels of myostatin inhibition were observed in both serum and muscle tissue. The most frequently occurring adverse events were injuries secondary to falls. There were no significant between‐group differences in the strength, functional, or imaging outcomes studied.DiscussionWe conclude that, although domagrozumab was safe in patients in limb‐girdle muscular dystrophy type 2I/R9, there was no clear evidence supporting its efficacy in improving muscle strength or function.
Vocal fold injection material does not preclude interpretation of laryngeal electromyography
Authors: Belsky Michael A. , Lin R. Jun , Rosen Clark A. , Munin Michael C. , Smith Libby J. 
Published: May 2021

AbstractIntroduction/AimsTemporary vocal fold injection (VFI) is a common treatment for acute and subacute vocal fold paralysis (VFP). Laryngeal electromyography (LEMG) is useful for diagnosing neurogenic causes of VFP. This study evaluated whether the presence of VFI material prevents interpretation of LEMG in patients with acute and subacute VFP.MethodsPatients with acute and subacute unilateral VFP (onset ≤6 mo) who underwent temporary VFI within 3 mo preceding LEMG were evaluated. A matched control group that did not undergo VFI was also studied. The LEMG team (laryngologist and electromyographer) performed and interpreted LEMG using a pre‐specified protocol, including qualitative and quantitative motor unit analysis.ResultsEighteen patients with VFI underwent LEMG successfully with interpretation of spontaneous activity and motor unit recruitment. Fourteen patients were seen in follow‐up to determine accuracy of established LEMG prognosis. Seven of seven subjects with poor LEMG prognosis did not recover vocal fold motion. Five of seven subjects with fair LEMG prognosis recovered vocal fold motion. Findings were similar for the control group.DiscussionVFI augmentation material did not prevent interpretation of meaningful LEMG data in patients with acute and subacute VFP, and accurate prognoses of vocal fold motion recovery were established.
Honeycomb scaffolds capable of ectopic osteogenesis: Histological evaluation of osteoinduction mechanism
Authors: Hayashi Koichiro , Ishikawa Kunio 
Published: May 2021

AbstractScaffolds capable of inducing ectopic osteogenesis (i.e., osteoinduction) have the potential to treat congenital and massive bone defects. However, the mechanisms underlying osteoinduction remain elusive, largely because of rapid tissue changes occurring early in the process. A model with decelerated osteoinduction is, therefore, needed. Here, we developed carbonate apatite honeycomb scaffolds capable of osteoinduction in rabbit muscle, which inherently exhibits minimal osteoinduction. The key events observed were: (1) fibrin accumulation in scaffolds at week 1; (2) appearance of tartrate‐resistant acid phosphatase (TRAP)‐ and RAM11‐positive cells and formation of collagen fibers and blood vessels between weeks 2 and 3; (3) appearance of osteocalcin‐positive cells and decrease in the number of TRAP‐positive cells between weeks 3 and 4; (4) continuous proliferation of osteocalcin‐positive cells at postoperative week 4 and formation of osteoid and mineralized tissues at weeks 8 and 12, respectively. These findings suggest that the appearance of TRAP‐positive cells that are considered foreign body giant cells is essential for collagen formation, angiogenesis, and osteogenesis. These insights may aid in the development of scaffolds for bone tissue engineering.
Bio‐mediated synthesis – A sustainable strategy for nanomaterials preparation: A comprehensive bibliometric review
Authors: Shen Yun , Zhang Li , Wang Ke , Li Xu , Li Jie , Zhang Shan , Zhao Hanghang , Jiang Xiaoxue , Guan Weisheng , Yang Li 
Published: May 2021

AbstractNanomaterials have been widely used in multi‐aspect because of their particular physicochemical properties. However, traditional physical and chemical synthetic methods of nanomaterials are costly, they are easy to produce toxic by‐products which are harmful to environment and human health. In recent years, the synthesis of nanomaterials via biological mediated method has shown great potential with the advantage of environmentally friendly, cost‐effective and high‐efficiency. Plants, microorganisms, and biological extracts are all excellent candidates for biosynthesis. Furthermore, these kinds of bio‐genic materials have been applied in many fields such as environment remediation, catalytic reaction, anti‐microbsis and anti‐tumor. Thus, in order to grasp the research progress and development trend of nanomaterials synthesized by bio‐mediated methods, a comprehensive overview is presented based on Web of Science database and bibliometric analysis. The results proved that the number of publications increased year by year from 2010 to 2020, India and China were the main two contributors. Some research institutions and researchers have formed their stable cooperative groups. Keywords analysis showed that the co‐occurrence network could be divided into four clusters, “green synthesis,” “AgNPs,” “AuNPs,” “nanoparticles,” and “leaf extract” were the most popular words. Moreover, publishing journals, highly cited articles and major disciplines were also studied. The review will provide valuable references for future research.
Influence of TiC nano‐particulates on the physical and mechanical properties of AA7150‐TiC MMC: Fabricated by advanced novel process
Authors: Madhukar Pagidi , Selvaraj N. , Kumar G.B. Veeresh , Rao C. S. P. , Mohammad Faruq , Seetharam R. , Chavali Murthy 
Published: May 2021

AbstractTiCnp reinforced AA7150 nanocomposites were prepared through a novel fabrication process (a combination of Vortex/Two‐step Stir Casting/Ultrasonication). The effect of TiCnp (0.5, 1.0, 1.5, and 2.0 wt.%) and ultrasonication on both microstructure behavior as well as mechanical properties were investigated at room temperature. Microstructural studies were analyzed through optical and scanning electron microscopy for grain size refinement, nanoparticle distribution and failure analysis. Grain refinement and homogeneous distribution of nanoparticles were achieved due to the ultrasonication effect. The mechanical properties increase with the increase of TiCnp wt.%. The optimal peak value at 175 MPa in tensile strength, 177.05 HV in microhardness, and 41.07 µm in grain size reduction were achieved at 1.5 wt.% of TiCnp content, which was around 48.31% and 17.4% enhanced in strength, in microhardness and 52.37% in grain size reduction. These peculiar achievements resulted from the homogeneous dispersion of TiC nano‐particulates in the nanocomposite material through a novel fabrication process.
Nanocomposites obtained by incorporation of silanized silver nanowires to improve mechanical properties and prevent fungal adhesion
Authors: de Menezes Beatriz Rossi Canuto , Sampaio Aline da Graça , da Silva Diego Morais , Montagna Larissa Stieven , Montanheiro Thaís Larissa do Amaral , Koga Ito Cristiane Yumi , Thim Gilmar Patrocínio 
Published: May 2021

AbstractIn this work, the surfaces of silver nanowires (AgNWs) were modified by silanization process to improve the mechanical and antibiofilm properties of polymethylmethacrylate (PMMA) dental resins. A two‐route methodology was used to silanize the AgNWs: first, a surface treatment using tetraethyl orthosilicate (TEOS) was performed to act as interface agent; and then, γ‐methacryloxypropyltrimethoxysilane (MPS) was used to insert functional groups compatible to the acrylic resin. PMMA/AgNWs composites were obtained using pristine (AgNWP) and modified AgNWs (AgNWM) at concentrations of 0.5 and 1.0 wt%. The mechanical (flexural and impact strength) and antibiofilm properties against Candida albicans was investigated. AgNWM showed an enhancement in the dispersion and adhesion within the PMMA matrix, which were responsible for improvements in the mechanical properties. Results of flexural strength showed significant improvements for the sample with incorporation of 0.5 wt% of AgNWM and no significative changes for the sample with AgNWP. In addition, a reduction of about 50% in the biofilm formation by C. albicans was observed for the samples with 0.5 and 1.0 wt% of AgNWM. The incorporation of silanized‐AgNWs into PMMA dental resins can combine improvements in antimicrobial activity and in the flexural strength, being a potential antimicrobial biomaterial for dental applications.
Fluorescence properties of yellow light emitting carbon quantum dots and their application for effective recognition of heavy metal ions in aqueous medium
Authors: Raj Savan K. , Rathod Nehal H. , Tripathi Balram , Patidar Rajesh , Kulshrestha Vaibhav 
Published: May 2021

AbstractWater‐dispersible and fluorescence‐stable carbon quantum dots (CQDs) have been synthesized at gram scale using pyrene as carbon precursor by employing the bottom‐up approach. X‐ray diffraction, FTIR, Raman spectroscopy and UV visible spectroscopy confirm the formation of CQDs. TEM images shows that size of the CQDs ranges from 2 to 5 nm. A detailed study of their optical and fluorescence characteristics was performed. Their aqueous dispersion radiates bright yellow light under UV lamp (365 nm). The research work includes derivation of their excitation wavelength, observation of influence of dilution on fluorescence and monitoring of emission intensity for about 4 months. The CQDs can effectively recognize the presence of heavy metal ions in aqueous medium at neutral pH via fluorescence quenching.
Characterization of anisotropic T2W signals from human knee femoral cartilage: The magic angle effect on a spherical surface
Authors: Pang Yuxi 
Published: May 2021

AbstractThe aim of the current study was to propose a generalized magic angle effect (gMAE) function for characterizing anisotropic T2W signals of human knee femoral cartilage with a spherical surface in clinical studies. A gMAE model function f(α, ε) was formulated for an orientation‐dependent (ε) transverse T2 (i.e., 1/R2) relaxation in cartilage assuming an axially symmetric distribution (α) of collagen fibers. T2W sagittal images were acquired on an adult volunteer's healthy knee at 3 T, and ROI‐based average signals S(ε) were extracted from angularly and radially segmented femoral cartilage. Compared with the standard MAE (sMAE) functions in the deep (DZ, α = 0°) and in the superficial (SZ, α = 90°) zones, a general form of R2 orientation‐dependent function f(α, ε) was fitted to S(ε), including an isotropic R2 contribution (internal reference [REF]). Goodness of fit was evaluated by root‐mean‐square deviations (RMSDs). An F‐test and a paired t‐test were respectively used to assess significant differences between the observed variances and means, with statistical significance set to p less than .05. As a symmetric orientation‐dependence function with a varying dynamic range, the proposed gMAE model outperformed the previous sMAE functions manifested by significantly reduced RMSDs in the DZ (0.239 ± 0.122 vs. 0.267 ± 0.097, p = .014) and in the SZ (0.183 ± 0.081 vs. 0.254 ± 0.085, p < .001). The fitted average angle α (38.5 ± 34.6° vs. 45.1 ± 30.1°, p < .43) and REF (5.092 ± 0.369 vs. 5.305 ± 0.440, p < .001) were smaller in the DZ than those in SZ, in good agreement with the reported collagen fibril microstructural configurations and the nonbound water contribution to R2 in articular cartilage. In conclusion, a general form of the magic angle effect function was proposed and demonstrated for better characterizing anisotropic T2W signals from human knee femoral cartilage at 3 T in clinical studies.
Association Between Nutrition Delivery, Modified Nutrition Risk In Critically III Score, and 28‐Day Mortality
Authors: Chada Radha Reddy , Chidrawar Sachin , Goud Bhagyasri A. , Maska Anita , Medanki Rajiv , Nagalla Balakrishna 
Published: May 2021

AbstractBackgroundNutrition delivery, is a key component in the management of critical illness. Traditional scoring systems are inadequate in the intensive care unit (ICU), as patients are sedated. Our study examines the associations between calorie and protein adequacy, 28‐day mortality, and modified Nutrition Risk in Critically Ill (mNUTRIC) score and identify at‐risk ICU patients who may benefit more from nutrition intervention.MethodsProspective observational study of adults admitted for >24h to the ICU of a tertiary care hospital during a period of 7 months. Data were collected on nutrition delivery, mNUTRIC score, use of mechanical ventilation, and ICU/hospital length of stay (LOS). Multivariate logistic regression analysis was done with 28‐day mortality as the primary outcome.ResultsTwo hundred forty‐eight patients were recruited for the study with 60% male, 40% female, mean age 60.8 ± 14.7, and body mass index of 24.2 ± 4.8. Patients with inadequate calorie and protein delivery had significantly higher 28‐day mortality than those with adequate provision (P=.032 and P =. 017). In bivariate logistic regression analysis, mNUTRIC score (odds ratio [OR], 1.802; 95% CI, 1.042–3.117; P = .035) and adequacy of energy (OR, 1.92) and protein (OR, 2.49) correlate with 28‐day mortality. The Kaplan‐Meier survival curve showed a survival benefit in the ≥80% energy and protein group among the total patients and was also significantly associated with lower hospital and ICU LOS, even after matching (log‐rank test, P < 0.001).ConclusionAdequacy of energy and protein to ≥80% may shorten ICU/hospital LOS and reduce 28‐day mortality among both high and low nutrition risk patients.
Partitioned formulation of contact‐impact problems with stabilized contact constraints and reciprocal mass matrices
Authors: González José A. , Kopačka Ján , Kolman Radek , Park Kwang‐Chun 
Published: May 2021

AbstractThis work presents an efficient and accuracy‐improved time explicit solution methodology for the simulation of contact‐impact problems with finite elements. The proposed solution process combines four different existent techniques. First, the contact constraints are modeled by a bipenalty contact‐impact formulation that incorporates stiffness and mass penalties preserving the stability limit of contact‐free problems for efficient explicit time integration. Second, a method of localized Lagrange multipliers is employed, which facilitates the partitioned governing equations for each substructure along with the completely localized contact penalty forces pertaining to each free substructure. Third, a method for the direct construction of sparse inverse mass matrices of the free bodies in contact is combined with the localized Lagrange multipliers approach. Finally, an element‐by‐element mass matrix scaling technique that allows the extension of the time integration step is adopted to improve the overall performance of the algorithm. A judicious synthesis of the four numerical techniques has resulted in an increased stable explicit step‐size that boosts the performance of the bipenalty method for contact problems. Classical contact‐impact numerical examples are used to demonstrate the effectiveness of the proposed methodology.