bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coulometry‐assisted quantitation in spray ionization mass spectrometry
Authors: Song Xiaowei , Chen Hao , Zare Richard N. 
Published: July 2020

AbstractThe concentration of target analyte in a mixture can be quantified by combining coulometric measurements with spray ionization mass spectrometry. A three‐electrode system screen printed on the polymer support acts both as the coulometry platform for electrochemical oxidation and the sample loading tip for spray ionization. After loading a droplet of the analyte solution onto the tip, two steps were taken to implement quantitation. First, the electrochemical oxidation potential was optimized with cyclic voltammetry followed by coulometric measurements to calculate the amount of oxidized analyte under a constant low voltage within a fixed period of time (5 s). Then, a high voltage (+4.5 kV) was applied to the tip to trigger spray ionization for measuring the oxidation yield from the native analyte ion and its oxidized product ion intensities by mass spectrometry. The analyte's native concentration is quantified by dividing the oxidized product's concentration (based on Coulomb's law) and the oxidation yield (estimated from mass spectrometry [MS] assuming that the parent and oxidation product have nearly the same ionization efficiencies). The workflow has an advantage in being free of any standard for constructing the quantitation curve. Several model compounds (tyrosine, dopamine, and angiotensin II) were selected for method validation. It was demonstrated that this strategy was feasible with an accuracy of ~15% for a wide coverage of different species including endogenous metabolites and peptides. As an example of its possible practical use, it was initially employed to make a bilirubin assay in urine.
Partial characterization and purification of phytase from Lactobacillus plantarum CRL1964 isolated from pseudocereals
Authors: Sandez Penidez Sergio H. , Velasco Manini Marina A. , Gerez Carla L. , Rollán Graciela C. 
Published: July 2020

AbstractCereals and pseudocereals are a rich source of nutrients and trace elements, but their dietary bioavailability is low due to the presence of phytate (IP6), an antinutritional compound with the ability to chelate cations and proteins. Phytase is an enzyme that catalyzes the hydrolysis of IP6 and it is used as an additive improving the nutritional quality of grain‐based foods. The aim of this study was to select lactic acid bacteria (LAB) isolated from pseudocereals with phytase activity, characterize their production and activity, and purify the enzyme. LAB strains isolated from grains and spontaneous sourdough of quinoa and amaranth were grown in the Man Rogosa and Sharpe medium where the inorganic phosphate (Pi) was replaced by 1% of IP6. Phytase activity was determined by measuring the Pi released from IP6. Phytase of Lactobacillus (L.) plantarum CRL1964 (PhyLP) showed the highest specific activity from 73 LAB evaluated. IP6 induces PhyLP production, which is at its maximum at the end of the exponential phase. PhyLP was thermostable and maintained its activity under acidic conditions. The enzymatic activity is stimulated by ethylenediaminetetraacetic acid, Co2+, and ascorbic acid. PhyLP was partially purified and showed a molecular mass of 55 kDa. L. plantarum CRL1964 and/or PhyLP have the potential to be included in the processing of cereal/pseudocereals based products for animal feed and/or the food industry improving its nutritional value.
Measurement Invariance of the Persistent Complex Bereavement Disorder Checklist With Respect to Youth Gender, Race, Ethnicity, and Age
Authors: Hill Ryan M. , Dodd Cody , Oosterhoff Benjamin , Layne Christopher M. , Pynoos Robert S. , Staine Mary Beth , Kaplow Julie B. 
Published: July 2020

AbstractThe Persistent Complex Bereavement Disorder (PCBD) Checklist was constructed to facilitate the developmentally sensitive assessment of proposed PCBD criteria in bereaved children and adolescents 8–18 years of age. Initial analyses of the PCBD Checklist provided support for the hypothesized two‐factor model. The purpose of the present study was to evaluate the measurement invariance of the PCBD Checklist with respect to gender (boys and girls), race/ethnicity (White, Black, and Hispanic youth), and age (school age, preadolescent, and adolescent youth). Participants were 594 youth (50.4% female) aged 7–18 years (M = 11.91, SD = 2.80) who were evaluated as part of standard care at a community‐based grief support center. Youth self‐identified as Hispanic (n = 184, 30.8%), non‐Hispanic white (n = 179, 30.0%), and African American/Black (n = 136, 22.8%). A series of stepwise, multigroup confirmatory factor analyses provided evidence in support of the PCBD Checklist's measurement invariance for all three groups concerning configural invariance, metric invariance, and scalar invariance. These results suggest that PCBD Checklist Criterion B and C scores are measuring similar latent variables, to a similar degree, across gender, race/ethnicity, and age. Establishing the cross‐group equivalence of the PCBD Checklist is an important endorsement of its generalizability and clinical utility in that it can be administered to diverse populations with confidence that it is measuring proposed PCBC diagnostic criteria similarly across subgroups.
A Safety Study of the Effects of 2‐Dimensional Shear Wave Elastography on Synaptic Morphologic Characteristics and Function in the Hippocampus of Neonatal Mice
Authors: Zhang Cheng , Li Nan , Li Changtian , Li Junlai 
Published: July 2020

ObjectivesThe aim of this study was to determine the effects of 2‐dimensional (2D) shear wave elastography (SWE) on synaptic morphologic characteristics and function in the neonatal mouse hippocampus and whether it affects the capacity for learning and memory later in life.MethodsWe divided neonatal mice into a control group and a 2D SWE group scanned for 10, 20, or 30 minutes. Hippocampal morphologic characteristics were assessed by hematoxylin–eosin and Nissl staining. Ultrastructures of hippocampal neurons were visualized by electron microscopy. Protein and messenger RNA expression levels of synaptophysin, N‐methyl‐d‐aspartate receptor 1 (NMDAR1), NMDAR2A, and NMDAR2B were quantified by a western blot and polymerase chain reaction, respectively. Learning and memory of adult mice were evaluated by the Morris water maze and the novel object recognition task.ResultsCompared with the control group, the hippocampal morphologic characteristics of the experimental groups did not differ under light microscopy, and the synaptic structures assessed by electron microscopy appeared normal. Western blot and polymerase chain reaction results showed that expression of synaptophysin, NMDAR1, NMDAR2A, and NMDAR2B were downregulated after exposure to 2D SWE, but there were no statistical differences between the experimental groups. This downregulation disappeared within 24 hours. The results of the Morris water maze and novel object recognition suggested that the 2D SWE scanning on neonatal mice had no effect on learning and memory in adulthood.ConclusionsThis study demonstrated that when the mice were exposed to neonatal cranial ultrasound by 2D SWE lasting for longer than 10 minutes, the expression of genes involved in synaptic function was affected, but this effect lasted no longer than 24 hours and did not affect learning and memory in adulthood.
Factors Associated With Distribution of Female Otolaryngology Residents in United States
Authors: Sulibhavi Anita , Kaufmann Matthew R. , Shetty Kunal R. , Wulu Jacqueline A. , Tracy Lauren F. , Levi Jessica R. 
Published: July 2020

ObjectiveThe gender balance within medicine, and specifically within otolaryngology, is equalizing. It is important to determine the factors that impact the distribution of female residents among otolaryngology programs in the United States to better understand factors that may affect these changing trends.Study DesignRetrospective Study.MethodsCross‐sectional analysis was performed using data from 2018 of otolaryngology residents at 90 programs across the United States. Each program's website was searched for a current resident roster. Data of geography, number of female faculty, number of female physicians in leadership positions, program setting, and program size were obtained. Statistical comparison of these factors with number of female residents was performed with P < .05 as significant.ResultsThere was a significant association between programs having a higher‐than‐average female faculty representation and a greater representation of female residents (P < .001). Larger residency programs were more likely to have greater female representation (P = .010). There was a slight predominance of both female residents and female faculty at urban programs (odds ratio [OR] = 1.27, P = .04; OR = 1.28, P = .03). Geographic location, presence of a female chairperson, and presence of a female residency program director were not associated with higher female‐to‐male resident ratio.ConclusionAvailability of female role models in faculty, along with program setting and size, may be more likely to promote greater female representation. Focusing on gender equality in the workplace can help promote diversity in the workforce and improve patient outcomes.Level of EvidenceNA Laryngoscope, 131:E367–E372, 2021
Effect of Ti3SiC2 content on the corrosion behavior of Al/Ti3SiC2 composite coatings
Authors: Jamshidi Rasoul , Bayat Omid , Heidarpour Akbar 
Published: July 2020

AbstractThe purpose of this study was to investigate the electrochemical corrosion properties of flame‐sprayed Al and Al/(5, 10, 15)% Ti3SiC2 coatings in a 3.5% NaCl solution. Scanning electron microscopy (SEM) and energy‐dispersive X‐ray spectroscopy (EDS) were used for analyzing the microstructural characteristics of the coatings. For examining the corrosion behavior of the coatings, a potentiodynamic polarization test and electrochemical impedance spectroscopy (EIS) were used. After the potentiodynamic polarization test, the SEM micrograph of coatings indicated that Ti3SiC2 particles played a significant role in pitting corrosion. The results of potentiodynamic polarization tests revealed that Al/Ti3SiC2 coating is nobler than that of the pure aluminum coating. On the contrary, the addition of Ti3SiC2 particles reduced the process of thickening the passive layer. The results of the EIS tests demonstrated that the presence of Ti3SiC2 particles significantly enhances the corrosion resistance of the coatings.
Effect of Macromolecular Crowders on the Self‐Assembly Process of Silk Fibroin
Authors: Dubey Priyanka , Seit Sinchan , Chowdhury Pramit K. , Ghosh Sourabh 
Published: July 2020

AbstractMacromolecular crowding is known to have a significant impact on the aggregation and folding of proteins. In this study, the role of different macromolecular crowders such as polyethylene glycol (PEG 200 and PEG 6000) and dextran (dextran 6000 and 70000) on the self‐assembly of silk fibroin protein is explored. The data show that crowders induce a clear transition from random coil to β‐sheet secondary conformation in the fibroin as demonstrated by ThT fluorescence spectroscopy, circular dichroism, and ATR‐FTIR findings. However, this transition is not observed in case of control sample (fibroin without crowders). Excluded volume effects accelerate the kinetics of self‐association of the fibroin protein. Increasing the molecular weight of crowders increases the required time for maximum aggregation. This study suggests that treating the fibroin with different macromolecular crowders has modulated the propensity of fibroin going into β‐sheet conformation.
Flexible and Conductive 3D Printable Polyvinylidene Fluoride and Poly(N,N‐dimethylacrylamide) Based Gel Polymer Electrolytes
Authors: Rahman Md Sazzadur , Shiblee MD Nahin Islam , Ahmed Kumkum , Khosla Ajit , Ogawa Jun , Kawakami Masaru , Furukawa Hidemitsu 
Published: July 2020

AbstractIn this work, 3D printable gel polymer electrolytes (GPEs) based on N,N‐dimethylacrylamide (DMAAm) and polyvinylidene fluoride (PVDF) in lithium chloride containing ethylene glycol solution are synthesized and their physicochemical properties are investigated. 3D printing is carried out with a customized stereolithography type 3D gel printer named “Soft and Wet Intelligent Matter‐Easy Realizer” and free forming GPE samples having variable shapes and sizes are obtained. Printed PVDF/PDMAAm‐based GPEs exhibit tunable mechanical properties and favorable thermal stability. Electrochemical proprieties of the printed GPEs are carried out via impedance spectroscopy in the temperature range of 25–90 °C by varying PVDF content. Ionic conductivity as high as 6.5 × 10−4 S cm−1 is achieved at room temperature for GPE containing low PVDF content (5 wt%) and conductivity of the GPEs is increased as temperature rises.
Multicompartment Polymeric Nanocarriers for Biomedical Applications
Authors: Nayanathara Umeka , Kermaniyan Sarah S. , Such Georgina K. 
Published: July 2020

AbstractMulticompartment polymeric nanocarriers which mimic the compartmentalized architecture of living cells have received considerable research attention in the biomedical field. The advancement of synthetic polymeric chemistry has allowed multicompartment polymeric nanocarriers to be tailored for biomedical applications such as drug delivery, encapsulated catalysis, and artificial cellular mimics. In this review, polymer‐based multicompartment nanocarriers (multicompartment micelles, multicompartment polymersomes, and capsosomes) have been discussed. This review focuses on multicompartment systems applied to biomedical applications over the last ten years. The synthetic procedures and structural properties that impact the specific application are also highlighted.
Effect of rotor cage's outer and inner radii on the inner flow field of the turbo air classifier
Authors: Yu Y. , Kong X. , Liu J. 
Published: July 2020

AbstractThe effects of rotor cage's outer and inner radii on flow field of the turbo air classifier are comparatively analyzed by numerical simulation using ANSYS‐FLUENT. The results of quantitative analysis show when the rotor cage's outer and inner radii are increased, the tangential velocity, radial velocity and upward axial velocity decrease in the annular region and near the entrance of the rotor cage. However, when the rotor cage's outer and inner radii are too large or too small, the tangential velocity and radial velocity will be fluctuated greatly. Moreover, the rotor cage's outer and inner radii directly influence the radial velocity distribution in the rotor cage channel. The rotor cage's outer and inner radii should not be too large or too small. Therefore, in the seven contrast rotor cage models, model 100–70 and 90–60 are selected to carry out the calcium carbonate classification experiments due to their small tangential velocity and radial velocity fluctuations and well‐distribution in the rotor cage channel. The experimental results reflect the characteristics of the numerically simulated flow field in the classifier.
Effect of tempering temperature on microstructure and properties of aluminium‐bearing high boron high speed steel
Authors: Qu Y. , He X. , Zhang X. , Fu H. , Cheng X. , Liu X. 
Published: July 2020

AbstractHeat treatment is of great significance to the performance improvement of high speed steel. Via heat treatment, the microstructure of high speed steel can be improved, thus greatly improving the material performance. The effect of tempering temperature on the microstructure of aluminium‐bearing high boron high speed steel (AB‐HSS) was investigated by optical microscope (OM), scanning electron microscope (SEM) and x‐ray diffraction (XRD). The hardness and wear resistance of the alloy at different tempering temperatures were tested by Rockwell hardness tester, micro‐hardness tester and wear tester. The experimental results indicate that the tempering microstructure of aluminium‐bearing high boron high speed steel consists of α‐Fe, M2B and a few of M23(C, B)6. Tempering temperature could greatly affect the wear resistance of materials. With the increase of tempering temperature, the wear resistance of aluminium‐bearing high boron high speed steel firstly increase and then decrease. The alloy tempered at 450 °C has the best wear resistance and minimum wear weight loss. This study provides a reference for the formulation of heat treatment process of aluminium‐bearing high boron high speed steel.
Quantitative Measurement of Metal Accumulation in Brain of Patients With Wilson's Disease
Authors: Li Gaiying , Wu Rong , Tong Rui , Bo Binshi , Zhao Yu , Gillen Kelly M. , Spincemaille Pascal , Ku Yixuan , Du Yasong , Wang Yi , Wang Xiaoping , Li Jianqi 
Published: July 2020

AbstractBackgroundCurrently, no study has evaluated metal accumulation in the brains of patients with Wilson's disease by using quantitative susceptibility mapping at 3T MRI. The objectives of this study were to qualitatively and quantitatively evaluate changes in magnetic susceptibility and R2* maps in deep gray matter nuclei to discriminate Wilson's disease patients from healthy controls and to evaluate their sensitivities in diagnosing Wilson's disease.MethodsMagnetic susceptibility and R2* maps and conventional T1‐weighted, T2‐weighted, and T2‐weighted fluid‐attenuated inversion recovery images were obtained from 17 Wilson's disease patients and 14 age‐matched healthy controls on a 3T MRI scanner. Differences between Wilson's disease and healthy control groups in susceptibility and R2* values in multiple deep nuclei were evaluated using a Mann‐Whitney U test and receiver operating characteristic curves. The correlations of susceptibility and R2* values with Unified Wilson's Disease Rating Scale score were also performed.ResultsMagnetic susceptibility and R2* can effectively distinguish different types of signal abnormalities. Magnetic susceptibility and R2* values in multiple deep nuclei of Wilson's disease patients were significantly higher than those in healthy controls. Magnetic susceptibility value in the substantia nigra had the highest area under the curve (0.888). There were positive correlations of the Unified Wilson's Disease Rating Scale score with susceptibility values in the caudate nucleus (r = 0.757, P = 0.011), putamen (r = 0.679, P = 0.031), and red nucleus (r = 0.638, P = 0.047), as well as R2* values in the caudate nucleus (r = 0.754, P = 0.012).ConclusionsQuantitative susceptibility mapping at 3T could be a useful tool to evaluate metal accumulation in deep gray matter nuclei of Wilson's disease patients. © 2020 International Parkinson and Movement Disorder Society
MicroRNA Deregulation in Blood Serum Identifies Multiple System Atrophy Altered Pathways
Authors: Pérez‐Soriano Alexandra , Bravo Paloma , Soto Marta , Infante Jon , Fernández Manel , Valldeoriola Francesc , Muñoz Esteban , Compta Yaroslau , Tolosa Eduard , Garrido Alicia , Ezquerra Mario , Fernández‐Santiago Rubén , Martí María‐José ,   the Catalan MSA registry (CMSAR)
Published: July 2020

AbstractBackground and ObjectivesMicroRNA (miRNA) changes are observed in PD but remain poorly explored in other α‐synucleinopathies such as MSA.MethodsBy genome‐wide analysis we profiled microRNA expression in serum from 20 MSA cases compared to 40 controls. By qPCR we validated top differentially expressed microRNAs in another sample of 20 MSA and 20 controls. We also assessed the expression of MSA differentially expressed microRNAs in two consecutive sets of 19 and 18 PD patients.ResultsIn the discovery set we identified 25 differentially expressed microRNAs associated with MSA, which are related to prion disease, fatty acid metabolism, and Notch signaling. Among these, we selected nine differentially expressed microRNAs and by qPCR confirmed array findings in a second MSA sample. MicroRNA‐7641 and microRNA‐191 consistently differentiated between MSA and PD.ConclusionsSerum microRNA changes occur in MSA and may reflect disease‐associated mechanisms. We identified two microRNAs which may differentiate MSA from PD. © 2020 International Parkinson and Movement Disorder Society
A new class of wideband microstrip falcate patch antennas with reconfigurable capability at circular‐polarization
Authors: Shirkolaei M. Mohammadi , Jafari M. 
Published: July 2020

AbstractA new wideband microstrip antenna, based on the falcate‐shaped patch, with reconfigurable capability at circular‐polarization is presented in this article. To achieve both properties of stable radiation characteristics and impedance matching across a broad bandwidth, the combination of the L‐probe feeding and falcate‐shaped patch is used. An RF‐switch is utilized to excite the L‐probes and generate either left‐hand circular polarization or right‐hand circular polarization over the wide operating bandwidth. A prototype of the proposed antenna is fabricated. An excellent agreement exists between the simulation and measurement results. The results reveal a wide impedance matching (|S11| <  − 10 dB), bandwidth of 55% (1.42‐2.5 GHz), and a 3 dB axial ratio bandwidth of 44% (1.6‐2.5 GHz). Furthermore, results confirm good radiation and impedance matching performance of the fabricated antenna over the wide bandwidth in comparison with previous related investigations. The reported reconfigurable antenna can be used as a suitable choice for GPS, ISM band, or RFID applications
The effect of pulmonary vessel suppression on computerized detection of nodules in chest CT scans
Authors: Gu Xiaomeng , Xie Weiyang , Fang Qiming , Zhao Jun , Li Qiang 
Published: July 2020

PurposeIn chest computed tomography (CT) scans, pulmonary vessel suppression can make pulmonary nodules more evident, and therefore may increase the detectability of early lung cancer. The purpose of this study was to develop a computer‐aided detection (CAD) system with a vessel suppression function and to verify the effectiveness of the vessel suppression on the performance of the pulmonary nodule CAD system.MethodsA CAD system with a vessel suppression function capable of suppressing vessels and detecting nodules was developed. First, a convolutional neural network (CNN)‐based pulmonary vessel suppression technique was employed to remove the vessels from lungs while preserving the nodules. Then, a CNN‐based pulmonary nodule detector was utilized to sequentially generate nodule candidates and reduce false positives (FPs). The performance levels of CAD systems with and without the vessel suppression function were compared using 888 three‐dimensional chest CT scans from the Lung Nodule Analysis 2016 (LUNA16) dataset. The pulmonary nodule detection results were quantitatively evaluated using the average sensitivity at seven predefined FP rates: 0.125, 0.25, 0.5, 1, 2, 4, and 8 FPs per scan.ResultsThe developed pulmonary nodule CAD system improved the average sensitivity to 0.977 from 0.950 owing to the addition of the vessel suppression function.ConclusionsThe vessel suppression function considerably improved the performance of the CAD system for pulmonary nodule detection. In practice, it would be embedded in CAD systems to assist radiologists in detecting pulmonary nodules in chest CT scans.