bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of magnetic molecularly imprinted polymer for dispersive solid‐phase extraction of valsartan and its determination by high‐performance liquid chromatography: Box‐Behnken design
Authors: Kaabipour Maryam , Khodadoust Saeid , Zeraatpisheh Fatemeh 
Published: December 2019

AbstractIn this work, core/shell magnetic molecularly imprinted polymer nanoparticles were synthesized for extraction and pre‐concentration of valsartan from different samples and then it was measured with high‐performance liquid chromatography. For preparation of molecularly imprinted polymer nanoparticles, Fe3O4 nanoparticles were coated with tetraethyl orthosilicate and then functionalized with 3‐(trimethoxysilyl) propyl methacrylate. In the next step, molecularly imprinted polymer nanoparticles were synthesized under reflux and distillation conditions via polymerization of methacrylic acid, valsartan (as a template), azobisisobutyronitrile and ethylene glycol dimethacrylate as cross linking. The properties of molecularly imprinted polymer nanoparticle were investigated by FTIR spectroscopy, field emission scanning electron microscopy, and X‐ray diffraction. Box‐Behnken design with the aid of desirability function was used for optimizing the effect of variables such as the amounts of molecularly imprinted polymer nanoparticles, time of sonication, pH, and volume of methanol on the extraction percentage of valsartan. According to the obtained results, the affecting variables extraction condition were set as 10 mg of adsorbent, 16 min for sonication, pH = 5.5 and 0.6 mL methanol. The obtained linear response (r2 > 0.995) was in the range of 0.005–10 µg/mL with detection limit 0.0012 µg/mLand extraction recovery was in the range of 92–95% with standard deviation less than 6% (n = 3).
Alternative Models of DSM‐5 Posttraumatic Stress Disorder in Portuguese Adolescents Exposed to Trauma and Childhood Adversity
Authors: Correia‐Santos Patrícia , Morgado Diogo , Maia Ângela C. , Levendosky Alytia , Jongenelen Inês , Pinto Ricardo J. 
Published: December 2019

AbstractThe factor structure of DSM‐5 posttraumatic stress disorder (PTSD) has been extensively debated, with evidence supporting the recently proposed seven‐factor hybrid model. However, few studies examining PTSD symptom structure have assessed the implications of these proposed models on diagnostic criteria and PTSD prevalence. In the present study, we examined seven alternative DSM‐5 PTSD models within a confirmatory factor analysis (CFA), using the Child PTSD Symptom Scale–Self‐Report for DSM‐5 (CPSS‐5). Additionally, we generated prevalence rates for each of the seven models by using a symptom‐based diagnostic algorithm and assessed whether substance abuse, depression, anxiety symptoms, and daily functioning were differentially associated with PTSD depending on the model used to derive the diagnosis. Participants were 317 adolescents aged 13–17 years (M = 15.93, SD = 1.23) who had experienced a DSM‐5 Criterion A trauma and/or childhood adversity. The CFA results showed good fit indices for all models, with the seven‐factor hybrid model presenting the best fit. The rates of PTSD diagnosis varied according to each model. The four‐factor DSM‐5 model presented the highest rate (30.6%), and the seven‐factor hybrid model presented the lowest rate (17.4%). Similar to the CFA analysis, the inclusion criteria for the diagnosis based on the hybrid model also presented the strongest associations with daily functional impairment, odds ratio (OR) = 1.48, 95% CI [1.25, 1.75]; and adverse childhood experiences, OR = 1.46, 95% CI [1.16, 1.82]. Research and clinical implications of these results are discussed, and suggestions for future investigation are presented.
African American Otolaryngologists: Current Trends and Factors Influencing Career Choice
Authors: Faucett Erynne A. , Newsome Hillary , Chelius Thomas , Francis Carrie L. , Thompson Dana M. , Flanary Valerie A. 
Published: December 2019

Objectives1) Identify factors that influence African American physicians to choose a career in otolaryngology; 2) determine the predominant practice setting for African American otolaryngologists who can be role models; and 3) determine if the presence of an African American otolaryngologist in academic setting influences career choice.MethodsSurvey methodology included a 15‐item survey to determine trends in practice and factors that influenced choice of specialty.ResultsThe results were reviewed for trends influencing career choice and practice location and stratified by age group. Most African American otolaryngologists are in academic practice and have subspecialty fellowship training. Enjoying medical student clerkship was the most frequently cited reason why African Americans chose otolaryngology as a career regardless of age. Early exposure was a driving factor in those 30 to 40 years old. Receiving mentorship was less influential in career choice for all age groups, but there was a positive association between those who were mentored in training and those who mentor faculty.ConclusionThe findings suggest the continued need for initiatives to increase African Americans in our specialty. Encouraging early exposure, intentional mentoring of students, and development of African American role models who can be mentors may help increase the number of African American otolaryngologist faculty. This can help our specialty achieve racial parity in a percentage that matches the number of African Americans in the United States workforce.Level of Evidence5 Laryngoscope, 130:2336–2342, 2020
Search for Natural Compounds That Increase Apolipoprotein A‐I Transcription in HepG2 Cells: Specific Attention for BRD4 Inhibitors
Authors: van der Krieken Sophie E. , van‐der Pijl Pieter C. , Lin Yuguang , Popeijus Herman E. , Mensink Ronald P. , Plat Jogchum 
Published: December 2019

AbstractAlthough increasing apolipoprotein A‐I (apoA‐I) might lower the cardiovascular disease risk, knowledge on natural compounds that elevate apoA‐I transcription is limited. Therefore, the aim of this study was to discover natural compounds that increase apoA‐I transcription in HepG2 cells. Since BRD4 inhibition is known to elevate apoA‐I transcription, we focused on natural BRD4 inhibitors. For this, the literature was screened for compounds that might increase apoA‐I and or inhibit BRD4. This resulted in list A, (apoA‐I increasers with unknown BRD4 inhibitor capacity), list B (known BRD4 inhibitors that increase apoA‐I), and list C (BRD4 inhibitors with unknown effect on apoA‐I). These compounds were compared with the compounds in two natural compound databases. This resulted in (1) a common substructure (ethyl‐benzene) in 60% of selected BRD4‐inhibitors, and (2) four compounds that increased ApoA‐I: hesperetin, equilenin, 9(S)‐HOTrE, and cymarin. Whether these increases are regulated via BRD4 inhibition and the ethyl‐benzene structure inhibits BRD4 requires further study.
Blood–Brain Barrier Is the Major Site for a Rapid and Dramatic Prostanoid Increase upon Brain Global Ischemia
Authors: Seeger Drew R. , Golovko Svetlana A. , Golovko Mikhail Y. 
Published: December 2019

AbstractWe and others have demonstrated a rapid and dramatic increase in brain prostanoids upon decapitation‐induced brain global ischemia and injury. However, the mechanism for this induction, including the cell types involved, are unknown. In the present study, we have validated and applied a pharmacological approach to inhibit prostanoid synthesis in the blood–brain barrier including endothelial cells. Our results indicate that a nonspecific cyclooxygenase (COX) inhibitor, ketorolac, does not pass the blood–brain barrier and does not enter red blood cells but penetrates endothelial cells. Ketorolac treatment did not affect basal prostanoid levels but completely prevented prostanoid induction upon global ischemia. These data indicate that basal prostanoids are synthesized in brain parenchyma cells, while inducible prostanoids are synthesized in the blood–brain barrier, most likely in endothelial cells. However, future studies with cell and COX isoform‐specific gene ablation are needed to further validate this conclusion. These findings identify endothelial cells as a possible target for the development of pharmacological approaches to selectively attenuate inducible prostanoid pools without affecting basal levels under brain ischemia, trauma, surgery, and other related conditions.
Synthesis of Ionic Dendrimers and Their Potential Use as Electrolytes for Lithium–Sulfur Batteries
Authors: Lebherz Tim , Weldin Dianne L. , Hintennach Andreas , Buchmeiser Michael R. 
Published: December 2019

AbstractA series of ionic dendrimers is synthesized and used as conducting salt in carbonate‐based electrolytes for Li/S‐cells. The resulting electrolytes display increasing viscosity with increasing chain length of the side chains, both in the first‐ and second‐generation dendrimers. Higher conductivity is observed for the first‐generation dendrimers as compared to the second‐generation ones. While all cells show high cycle stability, the differences in dendrimer structure also influence the electrochemical behavior of the Li–S cells. Thus, discharge capacities of the corresponding Li–S cells correlate both with the viscosity and the conductivity of the electrolytes. The best electrolyte system is obtained with a first‐generation dendrimer having a short side chain, D1‐1, having the lowest viscosity and the highest conductivity, which delivers discharge capacities of 1150 mAh gsulfur−1 @ 0.5 C and 780 mAh gsulfur−1 @ 1 C.
Technical Note: Correction of geometric x‐ray image intensifier distortion based on digital image correlation
Authors: Sanctorum Joaquim , Van Wassenbergh Sam , Aerts Peter , Dirckx Joris 
Published: December 2019

PurposeX‐ray image intensifiers (XRIIs) inevitably produce images suffering from geometric distortion. Presently, various local and global methods exist to correct for these distortions. However, the performance of global methods is limited for dominant local distortions, and local methods tend to suffer from patch discontinuity and are generally sensitive to noise. In this paper, a novel local method is presented based on digital image correlation (DIC), which does not suffer from patch discontinuity and noise.MethodsAs DIC is a very accurate and robust technique to analyze deformations, it is our candidate of choice to outperform the existing correction methods. The performance of our technique was first validated through distortion simulations. Next, it was validated experimentally for four different orientations of the XRII.ResultsA theoretical study on images suffering from a simulated distortion (including noise and blurring) yielded corrections with an average accuracy of (0.20 ± 0.04) pixels. We obtained experimental data with our 14" XRII (292 mm field of view), suffering from a maximum distortion between 9.6 and 12.9 mm, and an average distortion between (4.4 ± 1.3) mm and (6.1 ± 2.5) mm over the image field for the different orientations. For an adequate choice of the facet size in the DIC analysis (greater than 40 pixels), the weighted mean residual error of our method varied between (0.037 ± 0.003) mm and (0.054 ± 0.003) mm, regardless of the XRII orientation. The maximum residual error varied between 0.081 and 0.185 mm.ConclusionsFrom the simulations, we concluded that the proposed technique is affected by neither Gaussian noise nor blurring. Furthermore, it is shown that our method can reach an accuracy that is on par with or better than the current standard tools. The novel method is fast, requires minimal operator intervention and can be fully automated.
Theranostic markers for personalized therapy of spider phobia: Methods of a bicentric external cross‐validation machine learning approach
Authors: Schwarzmeier Hanna , Leehr Elisabeth Johanna , Böhnlein Joscha , Seeger Fabian Reinhard , Roesmann Kati , Gathmann Bettina , Herrmann Martin J. , Siminski Niklas , Junghöfer Markus , Straube Thomas , Grotegerd Dominik , Dannlowski Udo 
Published: December 2019

AbstractObjectivesEmbedded in the Collaborative Research Center “Fear, Anxiety, Anxiety Disorders” (CRC‐TRR58), this bicentric clinical study aims at identifying biobehavioral markers of treatment (non‐)response by applying machine learning methodology with an external cross‐validation protocol. We hypothesize that a priori prediction of treatment (non‐)response is possible in a second, independent sample based on multimodal markers.MethodsOne‐session virtual reality exposure treatment (VRET) with patients with spider phobia was conducted on two sites. Clinical, neuroimaging, and genetic data were assessed at baseline, post‐treatment and after 6 months. The primary and secondary outcomes defining treatment response are as follows: 30% reduction regarding the individual score in the Spider Phobia Questionnaire and 50% reduction regarding the individual distance in the behavioral avoidance test.ResultsN = 204 patients have been included (n = 100 in Würzburg, n = 104 in Münster). Sample characteristics for both sites are comparable.DiscussionThis study will offer cross‐validated theranostic markers for predicting the individual success of exposure‐based therapy. Findings will support clinical decision‐making on personalized therapy, bridge the gap between basic and clinical research, and bring stratified therapy into reach. The study is registered at ClinicalTrials.gov (ID: NCT03208400).
One‐bond 1J(15N─19F) spin–spin coupling constants of cationic fluorinating reagents: Insights from DFT calculations
Authors: Saielli Giacomo 
Published: December 2019

AbstractWe have investigated, by means of density functional theory protocols, the one‐bond 1J(15N─19F) spin–spin coupling constants in a series of fluorinating reagents, containing the N─F bond, recently studied experimentally. The results of the calculations show a very good linear relationship with the experimental values, even though only the M06‐2X(PCM)/pcJ‐2//B3LYP/6‐311G(d,p) level affords a very low mean absolute error. The calculations allow to analyze the various molecular orbitals contributions to the J coupling and to rationalize the observed positive sign, corresponding to a negative sign of the reduced spin–pin coupling constant K(N─F). Moreover, of the four Ramsey contributions, only the diamagnetic spin orbit is negligible, whereas the paramagnetic spin orbit and spin dipole terms decrease the magnitude of the Fermi contact (FC) term by an amount that goes from a minimum of 35% up to more than 60% of the FC term itself. Several effects have been investigated, namely, the contribution of the long‐range solvent reaction field, relativistic corrections, and conformational and vibrational effects.
Chemical shift of 129Xe dissolved in red blood cells: Application to a rat model of bronchopulmonary dysplasia
Authors: Friedlander Yonni , Zanette Brandon , Lindenmaier Andras , Sadanand Siddharth , Li Daniel , Stirrat Elaine , Couch Marcus , Kassner Andrea , Jankov Robert P. , Santyr Giles 
Published: December 2019

PurposeTo measure the chemical shift of hyperpolarized 129Xe dissolved in the red blood cells(δRBC) of a cohort of rats exposed to hyperoxia and intermittent hypoxia (IH) to mimic human bronchopulmonary dysplasia, and to investigate the effect of xenon‐blood distribution time on δRBC.MethodsδRBC was measured from spectra acquired using a chemical shift saturation recovery sequence from 15 Sprague‐Dawley rats exposed to hyperoxia‐IH and 10 age‐matched control rats. Sensitization to the xenon‐blood distribution time was achieved by varying the time between saturation pulses, τ. δRBC was compared with blood fraction measured by histology of the cohort and blood oxygenation measured directly using pulse oximetry following a hypoxic challenge in an identically exposed cohort.ResultsThe mean δRBC in the hyperoxia‐IH exposed rats was 0.55 ± 0.04 ppm lower than that of the healthy cohort (P = .0038), and this difference did not depend on τ (P = .996). The blood fraction of the exposed cohort was lower than that of the healthy cohort (P = .0397). Oximetry measurements showed that the baseline arterial oxygen saturation (SaO2) of each cohort was not different (P = .72), but after a hypoxic challenge, the SaO2 of the exposed cohort was lower than that of the healthy cohort (P = .003).ConclusionδRBC is reduced in rats exposed to hyperoxia‐IH compared with control rats. The change in δRBC is consistent with enhanced blood oxygen desaturation of the exposed cohort measured by pulse oximetry during a hypoxic challenge. This suggests that the observed change in δRBC reflects enhanced desaturation in the hyperoxia‐IH exposed cohort compared with the healthy cohort.
A Simple Near‐Infrared Fluorescent Probe for the Detection of Peroxynitrite
Authors: Wu Luling , Tian Xue , Han Hai‐Hao , Wang Jie , Groleau Robin R. , Tosuwan Paramabhorn , Wannalerse Boontana , Sedgwick Adam C. , Bull Steven D. , He Xiao‐Peng , James Tony D. 
Published: December 2019

AbstractHerein, we report the evaluation and synthesis of a reaction based fluorescent probe DCM‐Bpin for the detection of Peroxynitrite (ONOO−). DCM‐Bpin exhibits selective fluorescence off‐on response for ONOO− over other reactive oxygen species, including H2O2. Moreover, DCM‐Bpin is biocompatible and has been used to visualize exogenous ONOO− in HeLa cells.
Electrical, thermal, and mechanical properties of polypropylene/multiwalled carbon nanotube micromoldings
Authors: Zhou Shengtai , Hrymak Andrew N. , Kamal Musa R. 
Published: December 2019

AbstractIn this paper, properties of microparts molded from polypropylene/multiwalled carbon nanotubes (PP/CNT) composites were studied in detail. Results indicated that the percolation threshold of PP/CNT microparts shifted to higher filler concentrations when compared with their compression molded counterparts. Morphology observations revealed that the distribution of CNT is not uniform along the flow direction, which can significantly affect the properties of microparts. The thermal properties of PP and PP/CNT composites as well as corresponding microparts were investigated using differential scanning calorimetry and thermogravimetric analysis, respectively. Moreover, the mechanical properties of microparts were evaluated by nanoindentation analysis. Multicycling measurements indicated that the mechanical properties of microparts are both depth and location dependent. Both the hardness and elastic modulus increased with corresponding filler loading concentration of CNT below 3 and 7 wt%, respectively. Above those concentrations, both properties decreased with an increase of CNT concentration. This could be related to the state of filler distribution within the microparts.
Adaptive heading performance during self‐motion perception
Authors: Kuang Shenbing , Deng Hu , Zhang Tao 
Published: December 2019

AbstractPrevious studies have documented that the perception of self‐motion direction can be extracted from the patterns of image motion on the retina (also termed optic flow). Self‐motion perception remains stable even when the optic‐flow information is distorted by concurrent gaze shifts from body/eye rotations. This has been interpreted that extraretinal signals—efference copies of eye/body movements—are involved in compensating for retinal distortions. Here, we tested an alternative hypothesis to the extraretinal interpretation. We hypothesized that accurate self‐motion perception can be achieved from a purely optic‐flow‐based visual strategy acquired through experience, independent of extraretinal mechanism. To test this, we asked human subjects to perform a self‐motion direction discrimination task under normal optic flow (fixation condition) or distorted optic flow resulted from either realistic (pursuit condition) or simulated (simulated condition) eye movements. The task was performed either without (pre‐ and posttraining) or with (during training) the feedback about the correct answer. We first replicated the previous observation that before training, direction perception was greatly impaired in the simulated condition where the optic flow was distorted and extraretinal eye movement signals were absent. We further showed that after a few training sessions, the initial impairment in direction perception was gradually improved. These results reveal that behavioral training can enforce the exploitation of retinal cues to compensate for the distortion, without the contribution from the extraretinal signals. Our results suggest that self‐motion perception is a flexible and adaptive process which might depend on neural plasticity in relevant cortical areas.
Fabrication and properties of thermoplastic starch/montmorillonite composite using dialdehyde starch as a crosslinker
Authors: Peidayesh Hamed , Ahmadi Zahed , Khonakdar Hossein Ali , Abdouss Majid , Chodák Ivan 
Published: December 2019

AbstractThe poor mechanical properties and high water solubility of biodegradable thermoplastic starch (TPS) represent the main disadvantages of TPS in many applications. In this work, TPS film was prepared from a water solution of corn starch modified by 5 wt% dialdehyde starch (DAS) as crosslinking agent and 3 wt% montmorillonite (MMT) as reinforcing additive. Interactions occurring in the TPS films were investigated by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, XRD, DSC, dynamic mechanical thermal analysis (DMTA) and TGA. The results obtained fom FTIR spectroscopy and DSC suggest the formation of hydrogen bond interactions between the hydroxyl group of starch, DAS, the MMT layers and glycerol. DMTA indicated that the relaxation of films with DAS and MMT appears in a higher and broader temperature range due to the starch backbone stiffness; the extreme increase in the storage modulus confirmed the suggested interactions. The determination of the weight loss of the films in water indicated a significant increase of the water resistance of TPS due to incorporation of DAS and MMT. Changes in mechanical properties of the films containing DAS and clay were determined, showing a substantial increase in tensile strength from 2.7 to 6.7 MPa, while Young's modulus increased by 15 times for TPS modified with 5% DAS and 3% MMT. Therefore, the outcomes of this study confirmed that DAS is a suitable biomacromolecule crosslinker for starch and can significantly enhance TPS and TPS/MMT properties. © 2019 Society of Chemical Industry