bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Nature of the Lewis Acidic Sites in “TMA‐Free” Phenol‐Modified Methylaluminoxane
Authors: Zaccaria Francesco , Zuccaccia Cristiano , Cipullo Roberta , Budzelaar Peter H. M. , Macchioni Alceo , Busico Vincenzo , Ehm Christian
Published: October 2019

“Structural” AlMe2(bht) was found to be an integral building block of the “TMA‐free” olefin polymerization cocatalyst MAO/BHT (TMA = trimethylaluminum, MAO = methylaluminoxane, BHT = 2,6‐di‐tert‐butyl‐4‐methylphenol). NMR studies show that treatment of MAO/BHT with the neutral N‐donor pyridine (py) leads to selective generation of neutral AlMe2(bht)(py). The reaction of MAO/BHT with 2,2'‐bipyridine (bipy) generates cationic [AlMe(bht)(bipy)]+ fragments (bht = BHT phenolate), analogously to what happens when unmodified MAO is treated with bipy, causing [AlMe2(bipy)]+ formation. This suggests that the activation of an olefin polymerization precatalyst LnMX2 (X = Me or Cl) can occur via an indirect pathway involving [AlMeR]+ (R = Me or bht) transient species (rather than direct Cl/Me abstraction by the Al‐cages) not only when unmodified MAO is exploited but also in the case of “TMA‐free” BHT‐modified MAO. The high chemoselectivity of py for neutral Al adducts however presents a distinct difference to unmodified MAO. These observations indicate that a) “structural” TMA is converted into “structural” AlMe2(bht) upon reaction of MAO with BHT and that b) MAO/BHT is harder to ionize than unmodified MAO. A refined formula and cluster size estimation [(AlOMe)0.87(AlMe2bht)0.13]n (n = 57–84) is proposed for MAO/BHT based on this new experimental evidence, accounting for the presence of “structural” AlMe2(bht) units.
Synthesis of Substituted Thioamides from gem‐Dibromoalkenes and Sodiumsulfide
Authors: Morri Ashok K. , Thummala Yadagiri , Adepu Ramesh , Sharma Gangavaram V. M. , Ghosh Subhash , Doddi Venkata Ramana
Published: October 2019

A three‐component reaction of 1,1‐dibromoalkenes, sodium sulfide, and N‐substituted formamide for the synthesis of disubstituted thioamides has been developed. Various dibromoalkenes were found to be compatible under these conditions and gave corresponding thioamides in good to excellent yields.
Effect of pretreatment and low‐temperature low humidity drying on quality characteristics of coriander foliage
Authors: Priyadarshi Siddharth , Ramakrishna Chetana , Cheluvadasaiah Roopavathi , Naidu Madeneni Madhava
Published: October 2019

Pretreatment followed by low‐temperature low humidity drying was explored for efficient dehydration of coriander foliage to retain its quality characteristics. Newton, Page, Handerson & Pabis, Logarithmic & Midilli and Kucuk models were used to study the drying kinetics. Hygienic shelf‐stable green dried coriander foliage (HSSGDCF) obtained was evaluated for their flavour, physico‐chemical, microbial and sensory qualities during storage at ambient (65% RH, 27 ± 1°C) and accelerated (92% RH, 37 ± 1°C) conditions for 90 days. Logarithmic model with higher (R2 = 0.9997) and lower root mean square error value (0.0050) showed the best‐fitted model. Major volatiles identified in HSSGDCF were decanal (5.103%), 2‐decenal (10.021%), dodecanal (7.314%), 2‐dodecenal (7.684%), tetradecanal (8.509%), 13‐tetradecenal (19.393%) and decanoic acid decyl ester (6.051%). Degradation of chlorophyll, carotenoid and colour values were higher at 37 ± 1°C during storage. HSSGDCF was found to be microbiologically safe and sensorily acceptable at the end of 90 days at 27 ± 1°C.
Comprehensive utilization of edible mushroom Auricularia auricula waste residue—Extraction, physicochemical properties of melanin and its antioxidant activity
Authors: Liu Xin , Hou Ruolin , Wang Danting , Mai Mengxian , Wu Xiaoping , Zheng Mingfeng , Fu Junsheng
Published: October 2019

In order to promote the comprehensive utilization of the Auricularia auricula waste residue, the extraction process and the physicochemical properties of melanin from A. auricula waste residue were studied. Furthermore, the chemical antioxidant activity of waste residue melanin and its protective effect on cell oxidative injury induced by H2O2 were investigated. The results indicated that the ultrasonic‐assisted extraction process could be used to extract the melanin from A. auricula waste residue. Melanin had a good solubility in alkali solution and exhibited a certain stability to thermal. There was no significant difference between A. auricula melanin control group and waste residue melanin on ABTS, DPPH, and hydroxyl radical scavenging activity. Waste residue melanin significantly inhibited the cell death caused by H2O2, and the cell viability was restored to 98.09 ± 5.97% when the melanin concentration was 1.6 mg/ml. Cell morphology observation confirmed that the melanin ameliorated the morphological changes of cells induced by oxidative stress.
Baseline functional connectivity may predict placebo responses to accelerated rTMS treatment in major depression
Authors: Wu Guo‐Rong , Wang Xiaowan , Baeken Chris
Published: October 2019

Although in theory sham repetitive transcranial magnetic stimulation (rTMS) has no inherent therapeutic value, nonetheless, such placebo stimulations may have relevant therapeutic effects in clinically depressed patients. On the other hand, antidepressant responses to sham rTMS are quite heterogeneous across individuals and its neural underpinnings have not been explored yet. The current brain imaging study aims to detect baseline neural fingerprints resulting in clinically beneficial placebo rTMS treatment responses. We collected resting‐state functional magnetic resonance imaging data prior to a registered randomized clinical trial of accelerated placebo stimulation protocol in patients documented with treatment‐resistant depression (http://clinicaltrials.gov/show/NCT01832805). In addition to global brain connectivity and rostral anterior cingulate cortex (rACC) seed‐based functional connectivity (FC), elastic‐net regression and cross‐validation procedures were used to identify baseline intrinsic brain connectivity biomarkers for sham‐rTMS responses. Placebo responses to accelerated sham rTMS were correlated with baseline global brain connectivity in the rACC/ventral medial prefrontal cortex (vmPFC). Concerning the rACC seed‐based FC analysis, the placebo response was associated positively with the precuneus/posterior cingulate (PCun/PCC) cortex and negatively with the middle frontal gyrus. Our findings provide first brain imaging evidence for placebo responses to sham stimulation being predictable from rACC rsFC profiles, especially in brain areas implicated in (re)appraisal and self‐focus processes.
Investigation of charge interaction between fullerene derivatives and single‐walled carbon nanotubes
Authors: Delacou Clément , Jeon Il , Otsuka Keigo , Inoue Taiki , Anisimov Anton , Fujii Takenori , Kauppinen Esko I. , Maruyama Shigeo , Matsuo Yutaka
Published: October 2019

The charge interaction and corresponding doping effect between single‐walled carbon nanotubes (SWNTs) and various fullerene derivatives, namely, C60, phenyl‐C61‐butyric acid methyl ester (PC61BM), methano‐indenefullerene (MIF), 1′,1″,4′,4″‐tetrahydrodi[1,4]methanonaphthaleno[5,6]fullerene (ICBA), 1,4‐bis(dimethylphenylsilylmethyl)[60]fullerene (SIMEF‐1), and dimethyl(orthoanisyl) silylmethyl(dimethylphenylsilylmethyl)[60]fullerene (SIMEF‐2), are investigated. A variety of analytical techniques, including field‐effect transistors (FETs) made of horizontally aligned arrays of SWNTs, is used as a means of investigation. Data from different measurements have to be used to obtain a concrete evaluation for the fullerene‐applied SWNTs. The data collectively points toward the conclusion that fullerenes with high molecular orbital energy levels, namely, MIF, SIMEF‐1, SIMEF‐2, and PC61BM, induce p‐type doping, while fullerenes with low molecular orbital energy levels, namely, ICBA and C60, induce n‐type doping on the carbon nanotubes. Nevertheless, the SWNTs retained p‐type characteristics because n‐doping induced by the fullerenes are weak compared to the p‐doping of the water and oxygen on carbon nanotubes. This means that fullerene derivatives have the ability to fine‐tune the energy levels of carbon nanotubes, which can play a crucial role in carbon nanotube‐based electronics, such as solar cells, light‐emitting devices, and FETs.
The displacement study of 99mTc‐DTPA—Human serum albumin binding in presence of furosemide and metformin by using equilibrium dialysis and molecular docking
Authors: Chemlal Laila , Akachar Jihane , Makram Sanaa , Zoubir Brahim , Cherrah Yahia , Eljaoudi Rachid , Ibrahimi Azeddine , Faouzi Mly A.
Published: October 2019

The 99mTc‐DTPA (Technetium99m diethylenetriaminepentaacetic acid), is a radiopharmaceutical used in renal scintigraphy. The human serum albumin (HSA) binding site(s) for the 99mTc‐DTPA have never been characterized. This study will cover in vitro the binding rates of 99mTc‐DTPA on HSA and the 99mTc‐DTPA competition interactions with two drugs having known human serum albumin binding sites. Furosemide (FUR) and metformin (MET) were added to 99mTc‐DTPA solution (weight ratios 1/1 vol:vol) followed by the quantification of 99mTc‐DTPA binding rates to HSA (40 g/L) using equilibrium dialysis and the qualification of this binding using Molecular Modeling methods. The 99mTc‐DTPA binding rates to human serum albumin increased with the highest concentration. Both drugs FUR and MET displaced 99mTc‐DTPA binding. 99mTc‐DTPA could bind to human serum albumin in many locations in site I and I‐II, but strongly bound to site I through hydrogen bonds.
TRIM7 promotes proliferation and migration of vascular smooth muscle cells in atherosclerosis through activating c‐Jun/AP‐1
Authors: Ji Rongjing , Gu Yuanyuan , Zhang Jing , Gao Chuanyu , Gao Wanli , Zang Xiaobiao , Zhao Yonghui
Published: October 2019

Atherosclerosis (AS), with associated risk of stroke or cerebrovascular disease, is one of the most common causes of death globally. It has been well established that tripartite motif‐containing protein 7 Tripartite Motif‐containing 7 (Trim7), as an E3 ubiquitin protein ligase, is involved in protein ubiquitination and thus regulating cellular proliferation. Moreover, TRIM7 is upregulated in advanced carotid AS. However, the detailed mechanism of TRIM7 on regulation of AS remains unclear. In the present study, we firstly discovered that TRIM7 expression was robustly induced in platelet‐derived growth factor type BB‐treated vascular smooth muscle cells (VSMCs) and human atherosclerotic plaques. Functional approaches established that knockdown of TRIM7 inhibited proliferation and migration of VSMCs, as well as arrested the cell cycle at G1‐S, thus suppressing AS progression. Our results also identified that c‐Jun/activator protein 1 (AP‐1) signaling pathway was activated by TRIM7. Moreover, gain‐ and loss‐of‐function studies revealed that TRIM7 could promote proliferation and migration of VSMCs via activation of c‐Jun/AP‐1 signaling pathway. Finally, by using atherogenic apolipoprotein E‐deficient (apoE–/–) C57BL/6 mice with high‐fat diet AS model, we demonstrated that interference of TRIM7 could effectively mitigate in vivo AS via inactivation of c‐Jun/AP‐1 signaling pathway. In general, activation of c‐Jun/AP‐1 signaling pathway via TRIM7 could be an important mechanism in AS progression, thus shedding light on the development of novel therapeutics to the treatment of the disease.
Epigenetic regulation of amniotic fluid mesenchymal stem cell differentiation to the mesodermal lineages at normal and fetus‐diseased gestation
Authors: Zentelytė Aistė , Gasiūnienė Monika , Treigytė Gražina , Baronaitė Sandra , Savickienė Jūratė , Borutinskaitė Veronika , Navakauskienė Rūta
Published: October 2019

Human mesenchymal stem cells isolated from amniotic fluid (AF‐MSCs) demonstrate the potency for self‐renewal and multidifferentiation, and can, therefore, be a potential alternative source of stem cells adapted for therapeutic purposes. The object of this study is to evaluate the efficacy of MSCs from AF when the pregnancy is normal or when the fetus is affected during pregnancy to differentiate into mesodermal lineage tissues and to elucidate epigenetic states responsible for terminal adipogenic and osteogenic differentiation. The morphology of AF‐MSCs from two cell sources and the expression of the cell surface‐specific (CD44, CD90, and CD105) markers and pluripotency (Oct4, Nanog, Sox2, and Rex1) genes were quite similar and underwent mesodermal lineage differentiation because this is shown by the typical cell morphology and of genes’ expression specific for adipogenic (peroxisome proliferator‐activated receptor‐ɣ, adiponectin) and osteoblastic (alkaline phosphatase, osteopontin, and osteocalcin) differentiation. Terminal lineage‐specific differentiation was related to differential expression of miR‐17, miR‐21, miR‐34a, and miR‐146a, decreased levels of acetylated H4 and H3K9, trimethylated H3K4 and H3K9, and the retention of H3K27me3 along with a reduction in the levels of HDAC1, DNMT1, and PRC1/2 proteins (BMI1/SUZ12). No significant distinction could be identified in the levels of expression of all epigenetic or pluripotency markers between undifferentiated MSCs isolated from AF of normal gestation and pregnancy where the fetus was damaged and between those differentiated toward adipocytes or osteoblasts. The expressional changes of those marks and microRNAs that occurred during terminal differentiation to mesodermal tissues indicate subtle epigenetic regulation in AF‐MSCs when the condition of the fetus is healthy normal or diseased. More detailed studies of epigenetic mechanisms may offer a better understanding of AF‐MSCs differentiation in fetus‐diseased conditions and their usage in an autologous therapeutic application and prenatal disease research.
Long noncoding RNA DLGAP1‐AS1 promotes cell proliferation in hepatocellular carcinoma via sequestering miR‐486‐5p
Authors: Peng Xiaochun , Wei Fengmei , Hu Xiaoli
Published: October 2019

Hepatocellular carcinoma (HCC) is most prevalent tumor in liver and one of the most fatal cancers in the world. Long noncoding RNAs (lncRNAs) have been accepted as important regulators in carcinomas. But there are still many lncRNAs including DLGAP1‐AS1 unannotated in HCC. First of all, GEPIA suggested that DLGAP1‐AS1 presented high expression in HCC tissue samples relative to the normal tissues. Besides, overexpression of DLGAP1‐AS1 was also proved in HCC cell lines. Moreover, DLGAP1‐AS1 knockdown efficiently suppressed cell proliferation in HCC. Interestingly, miR‐486‐5p was predicted and validated to interact with DLGAP1‐AS1, while the level of miR‐486‐5p was significantly increased In HCC after DLGAP1‐AS1 knockdown. Moreover, we uncovered that ectopic expression of miR‐486‐5p induced suppression on HCC cell proliferation and that miR‐486‐5p inhibition offset the effect of DLGAP1‐AS1 silence on HCC cell proliferation and apoptosis. Furthermore, H3F3B was identified as target of miR‐486‐5p and was therefore positively regulated by DLGAP1‐AS1 in HCC. Of note, H3F3B upregulation partly revived the declined cell proliferative capacity in response to DLGAP1‐AS1 knockdown. To conclude, DLGAP1‐AS1 exerted its oncogenic role in HCC via miR‐486‐5p/H3F3B axis. Our new findings provided novel theoretical basis for discovery of therapeutic targets of HCC.
A retrospective analysis of hyponatremia during terlipressin treatment in patients with esophageal or gastric variceal bleeding due to portal hypertension
Authors: Han Xv , Li Jia , Yang Ji‐Ming , Gao Min , Wang Lei
Published: October 2019

Background and Aim

To explore the risk factors of hyponatremia caused by terlipressin.

Methods

Forty‐four patients with acute variceal bleeding treated with terlipressin from December 2016 to December 2018 were analyzed.

Results

During the treatment, serum sodium levels decreased from 137.78 to 126.59 mmol/L (P < 0.05), with an average decrease of 11.19 mmol/L. The serum sodium level decreased by less than 5 mmol/L in 12 patients (27.27%), by 5–10 mmol/L in 13 patients (27.27%), and by more than 10 mmol/L in 19 patients (43.18%). The difference in baseline serum sodium levels was statistically significant (P < 0.05), and the differences in baseline total bilirubin levels, Child‐Pugh scores, and model for end‐stage liver disease scores were also significant. Logistic regression analysis suggested that the initial sodium level was an independent risk factor for the decrease in the serum sodium concentration caused by terlipressin.

Conclusion

The incidence of hyponatremia is not low during treatment with terlipressin; a higher baseline serum sodium level is a risk factor for hyponatremia during treatment with terlipressin, and the mechanism may be related to endogenous vasopressin preconditioning.
An empirical prediction approach for seasonal fire risk in the boreal forests
Authors: Eden Jonathan M. , Krikken Folmer , Drobyshev Igor
Published: October 2019

The ability to predict forest fire risk at monthly, seasonal and above‐annual time scales is critical to mitigate its impacts, including fire‐driven dynamics of ecosystem and socio‐economic services. Fire is the primary driving factor of the ecosystem dynamics in the boreal forest, directly affecting global carbon balance and atmospheric concentrations of the trace gases including carbon dioxide. Resilience of the ocean–atmosphere system provides potential for advanced detection of upcoming fire season intensity. Here, we report on the development of a probabilistic empirical prediction system for forest fire risk on monthly‐to‐seasonal timescales across the circumboreal region. Quasi‐operational ensemble forecasts are generated for monthly drought code (MDC), an established indicator for seasonal fire activity in the Boreal biome based on monthly maximum temperature and precipitation values. Historical MDC forecasts are validated against observations, with good skill found across northern Eurasia and North America. In addition, we show that the MDC forecasts are an excellent indicator for satellite‐derived observations of burned area in large parts of the Boreal region. Our discussion considers the relative value of forecast information to a range of stakeholders when disseminated before and during the fire season. We also discuss the wider role of empirical predictions in benchmarking dynamical forecast systems and in conveying forecast information in a simple and digestible manner.
Sodium dodecyl sulfate free gel electrophoresis/electroelution sorting for peptide fractionation
Authors: Ramos Yassel , González Annia , Sosa‐Acosta Patricia , Perez‐Riverol Yasset , García Yairet , Castellanos‐Serra Lila , Gil Jeovanis , Sánchez Aniel , González Luis J. , Besada Vladimir
Published: October 2019

Shotgun proteomics based on peptide fractionation by using liquid chromatography has become the common procedure for proteomic studies, although in the very beginning of the field, protein separation by using electrophoresis was the main tool. Nonetheless, during the last two decades, the electrophoretic techniques for peptide mixtures fractionation have evolved as a result of relevant technological improvements. We also proposed the combination of sodium dodecyl sulfate polyacrylamide gel electrophoresis for protein fractionation and sodium dodecyl sulfate free polyacrylamide gel electrophoresis for peptide separation as a novel procedure for proteomic studies. Here, we present an optimized device for sodium dodecyl sulfate free polyacrylamide gel electrophoresis improving peptide recoveries respect to the established electrophoretic technique off gel electrophoresis meanwhile conserving the excellent resolution described for the former technique in slab gel based systems. The device simultaneously allows the separation and the collection of fractionated peptides in solution.
Preparation of porous magnetic molecularly imprinted polymers for fast and specifically extracting trace norfloxacin residue in pork liver
Authors: Zhang Yi , Xie Yang , Zhang Chungu , Wu Mingyu , Feng Shun
Published: October 2019

Here, magnetic molecularly imprinted polymers were designed for norfloxacin via oil‐in‐water emulsifier‐free emulsion method. It was prepared by simply mixing norfloxacin, methacrylic acid‐co‐ethylene glycol dimethacrylate copolymer, and Fe3O4 together at room temperature. Characterized by multiple analytical tools, the particle size, pore size, pore volume, specific surface area, and saturation magnetization of the product were about 30 µm, 10–500 nm, 2.92 mL/g, 105.84 m2/g, and 3.052 emu/g, respectively. And the adsorption capacity was high at 27.04 mg/g towards norfloxacin. Combined with ultra high performance liquid chromatography, it was used to determine norfloxacin in real samples. Average recoveries were above 77.44% with relative standard deviations between 1.21 and 6.85% at three spiked levels (n = 3) for lake water and pork liver. The determination was achieved for the most complex biosample pork liver spiked with norfloxacin low to 30 ng/g, about 100 times less than the maximum residue limit regulated by Commission of the European Communities. All evidences demonstrated that the magnetic molecularly imprinted polymers can be used in practice for monitoring norfloxacin either in environmental water or meat product with high accuracy and reliability.
Signal enhancement in supercritical fluid chromatography‐diode‐array detection with multiple injection
Authors: Sun Mingzhe , Turner Charlotta , Sandahl Margareta
Published: October 2019

To circumvent the detrimental effects of large‐volume injection with fixed‐loop injector in modern supercritical fluid chromatography, the feasibility of performing multiple injection was investigated. By accumulating analytes from a certain number of continual small‐volume injections, compounds can be concentrated on the column head, and this leads to signal enhancement compared with a single injection. The signal to noise enhancement of different compounds appeared to be associated with their retention on different stationary phases and with type of sample diluent. The diethylamine column gave the best signal to noise enhancement when acetonitrile was used as sample diluent and the 2‐picolylamine column showed the best overall performance with water as the sample diluent. The advantage of multiple injection over one‐time large‐volume injection was proven with sulfanilamide, with both acetonitrile and water as sample diluents. The multiple injection approach exhibited comparable within‐ and between‐day precision of retention time and peak area with those of single injections. The potential of the multiple injection approach was demonstrated in the analysis of sulfanilamide‐spiked honey extract and diclofenac‐spiked ground water sample. The limitations of this approach were also discussed.
Base‐deactivated and alkaline‐resistant chromatographic stationary phase based on functionalized polymethylsilsesquioxane microspheres
Authors: Huo Zhixia , Chen Lei
Published: October 2019

Vinyl, chloropropyl, and mercaptopropyl functionalized particles were prepared by a two‐step acidic/alkaline catalyzed co‐hydrolysis/condensation of methyltrimethoxysilane with a different silane precursor that carries chemically reactive functional group including vinyl, chloropropyl, and mercaptopropyl, respectively. The morphology, pore structure, and functional groups of the synthesized packings were studied by SEM, nitrogen adsorption‐desorption measurements, and solid‐state 13C 29Si NMR spectroscopy, respectively. The particles show ordered sphere, narrow particle size distribution, and mesoporous structure. The carbon contents of the microspheres are in the range of 17–19%, comparable to those of octadecyl‐bonded silica packings. The three‐kind of microspheres were directly used as packing materials for high‐performance liquid chromatography without size classification. The chromatographic performance of the columns was evaluated and compared with a commercially available C18 phase. The results revealed that these columns possess typical reversed‐phase chromatographic properties with increased hydrophobicity than polymethylsilsesquioxane and symmetric peaks for basic compounds. They were applied to the simultaneous separation of combination bendazol hydrochlorothiazide capsules containing polar and basic drugs with peaks identified by tandem with mass spectrometry. In general, a novel method is provided for the synthesis of different methyltrimethoxysilane‐derived microspheres for high‐performance liquid chromatography, which are advantageous for separating basic compounds.
Is Frailty Associated With Worse Outcomes After Head and Neck Surgery? A Narrative Review
Authors: Fu Terence S. , Sklar Michael , Cohen Marc , de Almeida John R. , Sawka Anna M. , Alibhai Shabbir M.H. , Goldstein David P.
Published: October 2019

Objective

Frailty has emerged as an important determinant of many health outcomes across various surgical specialties. We examined the published literature reporting on frailty as a predictor of perioperative outcomes in head and neck cancer (HNC) surgery.

Study Design

Narrative review with limited electronic database search and cross‐referencing of included studies.

Methods

PubMed was searched from inception until June 2019 to capture studies evaluating an association between frailty and perioperative outcomes among patients undergoing HNC surgery. Primary outcomes included mortality and morbidity, whereas secondary outcomes included in‐hospital cost, length of stay, readmission, and discharge disposition.

Results

We identified nine series examining frailty as a predictor of outcomes in HNC. The majority of studies (77%) identified patients using a large population‐based database such as the National Surgical Quality Improvement Project or National Inpatient Sample. Frailty measures applied in the HNC surgery literature include the modified frailty index, Groningen Frailty Indicator, and John Hopkins Adjusted Clinical Groups frailty‐defining diagnosis indicator. Most studies demonstrated a significant association between frailty and perioperative outcomes, including mortality, perioperative complications, and Clavien‐Dindo grade IV complications. Furthermore, frailty was associated with greater length of hospital stay, readmission rate, and likelihood of discharge to short‐term or skilled nursing facilities.

Conclusion

The current literature demonstrates the utility of frailty as a predictor of perioperative mortality and morbidity. Further research is needed to develop frailty screening measures in order to risk‐stratify patients and optimize modifiable factors preoperatively. Laryngoscope, 130:1436–1442, 2020
Numerical Simulations of Nanogel Synthesis Using Pulsed Electron Beam
Authors: Dahlgren Björn , Sabatino Maria Antonietta , Dispenza Clelia , Jonsson Mats
Published: October 2019

In this work, a new method for numerical simulation of the radiation chemistry of aqueous polymer solutions exposed to a sequence of electron pulses is presented. The numerical simulations are based on a deterministic approach encompassing the conventional homogeneous radiation chemistry of water as well as the chemistry of polymer radicals. The multitude of possible reactions in the macromolecular system is handled by allowing for a large number of macromolecular species. The speciation of macromolecular species is done to account for variations in molecular weight, number of alkyl radicals per chain, number of peroxyl radicals per chain, number of oxyl radicals per chain, and number of internal loops. As benchmarking, previously published results from a series of experiments on pulsed irradiation of aqueous poly(N‐vinylpyrrolidone) (PVP) solutions are used. The numerical simulations clearly show that the pulsed nature of the radiation must be accounted for. The simulations qualitatively reproduce the experimentally observed impact of initial gas saturation (air and N2O) and polymer concentration on the molecular chain length upon irradiation. The formation of double bonds as a function of dose as well as the impact of effective dose rate on the final chain length are also qualitatively reproduced in the simulations.
Screening, identification, and low‐energy ion modified breeding of a yeast strain producing high level of 3‐hydroxypropionic acid
Authors: Li Wen , Wang Tao , Dong Yuwei , Li Tongxiang
Published: October 2019

3‐Hydroxypropionic acid (3HP) is an important platform chemical with a wide range of applications. The biological preparation of this compound is safe and low cost. In this study, orchard soil and human waste were used as raw materials to screen microbial strains that could produce 3HP in selective medium containing varying amounts of propionic acid. A yeast strain that can use propionic acid as substrate and produce 48.96 g/L 3HP was screened. Morphological observation, physiological and biochemical identification, and 26s rDNA sequencing identified the IS451 strain as Debaryomyces hansenii. The low‐energy ion N+, with the energy of 10 keV and a dose of 70 × 2.6 × 1013 ions/cm2, was implanted into the IS451 strain. The mutant strain WT39, whose 3HP titer reached 62.42 g/L, was obtained. The strain exhibited genetic stability and tolerance to high concentrations of propionic acid and was considered to have broad application prospects.
Cell penetrating peptide functionalized perfluorocarbon nanoemulsions for targeted cell labeling and enhanced fluorine‐19 MRI detection
Authors: Hingorani Dina V. , Chapelin Fanny , Stares Emma , Adams Stephen R. , Okada Hideho , Ahrens Eric T.
Published: October 2019

Purpose

A bottleneck in developing cell therapies for cancer is assaying cell biodistribution, persistence, and survival in vivo. Ex vivo cell labeling using perfluorocarbon (PFC) nanoemulsions, paired with 19F MRI detection, is a non‐invasive approach for cell product detection in vivo. Lymphocytes are small and weakly phagocytic limiting PFC labeling levels and MRI sensitivity. To boost labeling, we designed PFC nanoemulsion imaging probes displaying a cell‐penetrating peptide, namely the transactivating transcription sequence (TAT) of the human immunodeficiency virus. We report optimized synthesis schemes for preparing TAT co‐surfactant to complement the common surfactants used in PFC nanoemulsion preparations.

Methods

We performed ex vivo labeling of primary human chimeric antigen receptor (CAR) T cells with nanoemulsion. Intracellular labeling was validated using electron microscopy and confocal imaging. To detect signal enhancement in vivo, labeled CAR T cells were intra‐tumorally injected into mice bearing flank glioma tumors.

Results

By incorporating TAT into the nanoemulsion, a labeling efficiency of ~1012 fluorine atoms per CAR T cell was achieved that is a >8‐fold increase compared to nanoemulsion without TAT while retaining high cell viability (~84%). Flow cytometry phenotypic assays show that CAR T cells are unaltered after labeling with TAT nanoemulsion, and in vitro tumor cell killing assays display intact cytotoxic function. The 19F MRI signal detected from TAT‐labeled CAR T cells was 8 times higher than cells labeled with PFC without TAT.

Conclusion

The peptide‐PFC nanoemulsion synthesis scheme presented can significantly enhance cell labeling and imaging sensitivity and is generalizable for other targeted imaging probes.
FatSegNet: A fully automated deep learning pipeline for adipose tissue segmentation on abdominal dixon MRI
Authors: Estrada Santiago , Lu Ran , Conjeti Sailesh , Orozco‐Ruiz Ximena , Panos‐Willuhn Joana , Breteler Monique M. B. , Reuter Martin
Published: October 2019

Purpose

Introduce and validate a novel, fast, and fully automated deep learning pipeline (FatSegNet) to accurately identify, segment, and quantify visceral and subcutaneous adipose tissue (VAT and SAT) within a consistent, anatomically defined abdominal region on Dixon MRI scans.

Methods

FatSegNet is composed of three stages: (a) Consistent localization of the abdominal region using two 2D‐Competitive Dense Fully Convolutional Networks (CDFNet), (b) Segmentation of adipose tissue on three views by independent CDFNets, and (c) View aggregation. FatSegNet is validated by: (1) comparison of segmentation accuracy (sixfold cross‐validation), (2) test–retest reliability, (3) generalizability to randomly selected manually re‐edited cases, and (4) replication of age and sex effects in the Rhineland Study—a large prospective population cohort.

Results

The CDFNet demonstrates increased accuracy and robustness compared to traditional deep learning networks. FatSegNet Dice score outperforms manual raters on VAT (0.850 vs. 0.788) and produces comparable results on SAT (0.975 vs. 0.982). The pipeline has excellent agreement for both test–retest (ICC VAT 0.998 and SAT 0.996) and manual re‐editing (ICC VAT 0.999 and SAT 0.999).

Conclusions

FatSegNet generalizes well to different body shapes, sensitively replicates known VAT and SAT volume effects in a large cohort study and permits localized analysis of fat compartments. Furthermore, it can reliably analyze a 3D Dixon MRI in ∼1 minute, providing an efficient and validated pipeline for abdominal adipose tissue analysis in the Rhineland Study.
Spatial Gradients in Population Characteristics of Ohio River Sauger and Implications for a Length-Based Regulation
Authors: Pritt Jeremy J. , Depew Michael A. , Herrala Jason R. , Hirst Jana , Jansen Craig R. , Zipfel Katherine J.
Published: October 2019

Sauger Sander canadensis provide a popular, harvest-oriented fishery throughout the Ohio River and are managed jointly by the state fisheries resource agencies through the Ohio River Fisheries Management Team. For more than two decades, the Ohio River Sauger population has been dominated by small (<356 mm), young (<3 years old) individuals. Recently, Sauger abundance in the Ohio River has been near or below long-term averages. Together, these observations prompted concern that overfishing may be occurring and that more restrictive harvest regulations may be necessary. We summarized Sauger population characteristics (abundance of age-0 Saugers, abundance of Saugers ≥280 mm TL, growth, and mortality) based on data from Ohio River Fisheries Management Team population assessments conducted during the period of 2005–2017 and modeled the potential outcomes of applying a 356-mm minimum length limit. During the period 2005–2017, abundance of age-0 Saugers and abundance of Saugers ≥280 mm TL was greater with distance downstream but generally declined through time. Growth rates and total annual mortality rates increased with distance downstream and had no apparent temporal trends. Yield-per-recruit models showed that where Saugers grow fastest (i.e., downstream pools), implementing a minimum length limit could improve size structure and increase yield. However, where Saugers grow slowly (upstream pools), size structure would only increase marginally, and yields would likely decrease with a minimum length limit. Upstream to downstream gradients in Sauger population characteristics may therefore lead to differences in the effectiveness of length-based regulations among Ohio River pools. Fisheries managers must therefore consider trade-offs between the size of fish at harvest and yield before implementing minimum length limits.
Nursing students' perception of patient‐centred care: A qualitative study
Authors: Ghane Golnar , Esmaeili Maryam
Published: October 2019

Aim

This study aimed to explain the understanding of nursing students from the concept of patient‐centred care.

Design

This is an explorative and descriptive‐qualitative design.

Methods

The participants consisted of 15 nursing students who were selected through purposeful sampling, and data were collected through in‐depth, semi‐structured interviews and analysed using a qualitative content analysis.

Results

Data analysis led to the identification of three categories including the following: the inevitability of patient‐centred care, the patient‐centredness in comprehensive care and the importance of nursing process in patient‐centred care. Introducing students to the concept of patient‐centred care and how it can be achieved seems necessary during nursing education. Introducing a module on patient‐centred care to the nursing curriculum is suggested to familiarize students with this concept.
Unexpected Molecular Structure of a Putative Rhenium‐Dioxo‐Benzocarbaporphyrin Complex. Implications for the Highest Transition Metal Valence in a Porphyrin‐Type Ligand Environment
Authors: Alemayehu Abraham B. , Vazquez‐Lima Hugo , Teat Simon J. , Ghosh Abhik
Published: October 2019

A combination of quantum chemical calculations and synthetic studies was used to address the possibility of very high (>6) valence states of transition metals in porphyrin‐type complexes. With corrole as a supporting ligand, DFT calculations ruled out Re(VII) and Ir(VII) dioxo complexes as stable species. Attempted rhenium insertion into benzocarbaporphyrin (BCP) ligands on the other hand led to two products with different stoichiometries – Re[BCP]O and Re[BCP]O2. To our surprise, single‐crystal structure determination of one of the complexes of the latter type indicated an ReVO center with a second oxygen bridging the Re−C bond. In other words, although the monooxo complexes Re[BCP]O are oxophilic, the BCP ligand cannot sustain a trans‐ReVII(O)2 center. The search for metal valence states >6 in porphyrin‐type ligand environments must therefore continue.
Sedation practices in pediatric patients with acute lymphoblastic leukemia
Authors: Nugent Bethany D. , Davis Peter J. , Noll Robert B. , Tersak Jean M.
Published: October 2019

Background

The 5‐year survival for pediatric acute lymphoblastic leukemia (ALL) is greater than 90%. One late effect of pediatric ALL associated with numerous long‐term difficulties is neurocognitive deficits. The experience at our institution, as well as conversations with oncologists at other institutions, suggests an increase in the use of sedation during lumbar punctures (LPs) for treatment of pediatric ALL. Among the most common Children's Oncology Group (COG) ALL protocols, approximately 30 LPs are performed over 2‐3 years. Studies in animals reveal that sedation drugs may harm the developing brain. Gaps in knowledge exist regarding their use in children, particularly repeated exposures. The purpose of this study is to summarize sedation practices for LPs related to the treatment of ALL at COG institutions.

Methods

Responsible Individuals (RIs) of the Cancer Control Committee of COG were invited to complete an internet‐based survey about sedation practices at their institutions.

Results

Surveys were sent to 103 RIs with a 62% response rate (N = 64). A combined 2018 new patients with ALL were seen each year (mean = 31.5, range = 3‐110) at the participating institutions. The majority (96%) of children with ALL received sedation for LPs. While there was considerable variability across institutions in the type of sedation given, the most common was propofol alone (n = 36, 56%).

Conclusions

A substantial number of children with ALL receive sedation for LPs; however, there is variation in the medication used. Better understanding of sedation practices in children with ALL may inform future research to investigate which methods are the safest, with an emphasis on long‐term neurocognitive late effects.
Aggregation selectivity of amyloid β1‐11 peptide in aqueous ionic liquid solutions
Authors: Takekiyo Takahiro , Yamada Natsuki , Amo Taku , Yoshimura Yukihiro
Published: October 2019

Understanding the aggregation selectivity of peptide fragments of full‐length proteins in aqueous solutions with ionic liquids (ILs) could facilitate the elucidation of the relationship between the IL‐protein interactions and structural behavior of intrinsically disordered proteins (IDPs) such as amyloid β protein following the addition of ILs. In the present study, we investigate structural changes in peptide fragment 1‐11 (Aβ1‐11) of amyloid β protein in aqueous solutions with two ILs including 1‐butyl‐3‐methylimidazolium thiocyanate ([bmim][SCN]) and ethylammonium nitrate (EAN) using optical spectroscopy. The addition of [bmim][SCN], which exhibits strong protein denaturant ability, induced the formation of an intermolecular β‐sheet structure (aggregation), while the addition of EAN, which has a weaker denaturant ability compared with [bmim][SCN], did not cause aggregation. Since the role of cations is related to the ability to mask the charged residues of Aβ1‐11, the aggregation selectivity of Aβ1‐11 depends on the anionic species and anions with high denaturation ability enhanced aggregation. Our results demonstrated that the structural change in peptide fragment in aqueous IL solutions could be used to evaluate the relationship between the IL‐protein interactions and aggregation selectivity in IDPs in aqueous IL solutions.
Usefulness of bronchoalveolar lavage in a French pediatric cohort with hypersensitivity pneumonitis
Authors: Wanin Stéphanie , Malka‐Ruimy Clara , Deschildre Antoine , Nathan Nadia , Reboux Gabriel , Reix Philippe , de Blic Jacques , Houdouin Véronique
Published: October 2019

Background

Hypersensitivity pneumonitis (HP) is a rare interstitial lung disease in children, and very little data are available on the frequency, diagnosis, and outcomes of HP. In a pediatric cohort with HP, the characteristics of the CD4/CD8 lymphocyte ratio are often described as nonspecific.

Methods

We used the National French Database (RespiRare) to collect data from the last decade on HP. The diagnosis of HP was defined by the presence of a relevant exposure, clinical symptoms, and compatible lung imaging radiology and was usually defined by positive precipitins antibodies.

Results

A total of 16 children with a mean age of 10 years (4‐13) presented with HP. All children presented with dyspnea on exertion. Diffuse ground‐glass opacity was present in all computed tomography (CT) scans. Research guided by a questionnaire and precipitins antibodies against the corresponding antigens showed that patients were positive for contact with birds with or without fungi. Bronchoalveolar lavage (BAL) was performed in 12 children. The total cell counts were elevated in BAL fluid, with a mean value of 36% lymphocytes. The CD4/CD8 lymphocyte ratio was below one for all children.

Conclusion

BAL in our pediatric cohort with HP had the same characteristics as that of adults with HP. An HP diagnosis must be considered when dyspnea on exertion and diffuse ground‐glass opacity are observed. Carrying out BAL and serological tests can help diagnose and avoid lung biopsy.
Teens' everyday information practices on mobile media: “catching up” and “reaching out”
Authors: Kimm Junoh , Boase Jefferey
Published: October 2019

Mobile media have become a central part of everyday life for many teens. We examine how teens use the media to access diverse information to maintain and reconnect with personal relationships in their personal networks. Based on semi‐structured interviews with 81 teens from ethnically and economically diverse backgrounds, we find that teens generally have broad networks of ties with whom they communicate through both face‐to‐face interactions and mobile media. To maintain these networks, the teens in our study use information that they either unexpectedly encounter or purposely seek out on various platforms available on their mobile devices to “reach out” to dormant ties and “catch up” with active ties.
Understanding the information landscape of indigenous elders' knowledge and cultural practices
Authors: Haines Jelina , Du Jia Tina , Geursen Gus , Trevorrow Ellen
Published: October 2019

This visual presentation is a timely topic while celebrating the year of Indigenous languages and cultures. However, the continuing impact of colonization, displacement, and oppression still lingers. Cultural traditions, once central to all knowledge practices, have been suppressed or subjugated by Western hegemony. This paper aimed to qualitatively articulate the importance of understanding the information landscape of Indigenous Elders, their role in the community and the correlation of Indigenous knowledge and health informatics. The informatic nature of Elders' knowledge was mapped and guided by two Indigenous Elders from the Ngarrindjeri community in South Australia. Video interviews were transcribed and coded using the Xmind mapping software. Limitations on articulating the knowledge map in its entirety were expected. Research implications will provide excellent opportunities for future research in both cultural, digital and health informatics.
The role of information cues on users' perceived credibility of online health rumors
Authors: Song Xiaokang , Zhao Yuxiang (Chris) , Song Shijie , Zhu Qinghua
Published: October 2019

There are a lot of health rumors on social media that can lead to misunderstandings, health risks, and negative health behaviors. Understanding what makes health rumors credible becomes an important research topic. Based on elaboration likelihood model (ELM), this study aimed to explore the impact of three information cues (quality cues, attractiveness cues, and affective polarity) on the credibility of health rumors, under different levels of health literacy and personal involvement. We conduct an online experiment and obtain data from 218 participants. The preliminary results show that the quality cues and attractiveness cues of health rumors have negative impacts on credibility. Dread health rumors are more credible than wish rumors. Health literacy has a significant negative moderating effect between quality cues and health rumor credibility, and personal involvement has a significant positive moderating effect between attractiveness cues and health rumor credibility. This study offers insights on the intervention of social media health rumors.
Librarian role‐playing as a method for assessing student information literacy skills
Authors: Rieh Soo Young , Bradley Doreen , Brennan‐Wydra Emma , Culler Tori , Hanley Elizabeth , Kalt Marley
Published: October 2019

Researchers and practitioners alike have long investigated the effectiveness of information literacy instruction, addressing what to measure regarding student learning and how to measure it. The purpose of this paper is twofold. First, we review measures and methods that have been developed to assess student learning that results from information literacy instruction. We then present a study in which we employed a new research method of librarian role‐playing to examine the extent to which college students are capable of demonstrating their information literacy skills while acting as an academic librarian. We also incorporated card‐sorting exercises, asking about their perceived search difficulty before and after the role‐playing exercise. Ten role‐playing sessions were conducted by recruiting undergraduate students who had attended an information literacy instruction session 3–4 months prior as a part of their English writing course. Results showed that the librarian role‐playing method provided opportunities for participants to recall and reflect upon what they learned from information literacy instruction effectively. Results also indicated that the role‐playing method is potentially effective in developing students' meta‐cognition about their search behavior.
Users' visual attention flow on the search result page of digital cultural heritage collection
Authors: Wu Dan , Xu Shuang , Xu Xiaoyun , Chen Xi
Published: October 2019

Cultural heritage breathes a new life with digital technologies and the internet. Digitization of cultural heritage artifacts do represent new materials and new contexts for research and practice. It is important to know how the public access and browse online collections of digital cultural heritage. This paper presents an eye‐tracking experiment on Digital Dunhuang, which is the most famous digital cultural heritage project in China, and identifies users' visual attention in search engine results pages (SERP). The results show how visual attention allocates in each area of interest (AOI), and the AOIs are browsed back and forth until the information needs are satisfied.