bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid homogenization preparation of the mussel‐inspired hydrophilic separator for high power lithium‐ion batteries
Authors: Li Jingde , Bi Songhu , Li Meimei , Xian Yupei , Shui Yonggang , Yao Yongyi , Wu Mengqiang
Published: February 2020

In this work, a thin and smooth PEI/Dopamine coating layer was immobilized onto the PP separator skeleton via co‐deposition of dopamine and polyethyleneimine (PEI, 600 Da). The PEI/Dopamine decorated separator was characterized by SEM, FT‐IR/ATR, XPS, UV, EDX, DSC, contact angle and electrochemical methods. The PEI/Dopamine decorated separator showed stable thermal performance. The pure water contact angle was reduced after PEI/Dopamine coating modification. The electrolyte uptake was improved by reason of the boosted compatibility between separator and liquid electrolyte. Meanwhile, the high absorption rate of electrolytes and the introduction of polar functional groups promote the desolvation of lithium ions and the dissociation of lithium salts, thereby improving the ionic conductivity. Batteries assembled with PEI/Dopamine decorated separator displayed more stable cycle performance and the C‐rate performance was greatly enhanced. These results demonstrate that PEI/Dopamine decorated separator is expected to be an ideal choice for high power lithium‐ion batteries.
Superhydrophobic polytetrafluoroethylene nanofiber membranes prepared by vacuum sintering and their application in vacuum membrane distillation
Authors: Zhou Tao , Zhong Qin , Li Jingde , Yao Yongyi , Xiang Ruili , Zhu Puxin
Published: February 2020

Electrospinning‐sintering is a general strategy to fabricate polytetrafluoroethylene (PTFE) nanofibrous membranes. In this study, vacuum atmosphere was created in the sintering process to obtain pure PTFE fibers. The effect of vacuum pressure on fiber morphology and material component of the sintered membrane was investigated by scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS) characterization. A proper vacuum condition was believed to be beneficial to decrease poly(vinyl alcohol) residual and creating nanosize structures on the fiber surface, as porous, which contributes to a secondary roughness, while insignificantly influence membrane strength. As a result, the prepared membrane was superhydrophobicity with enhanced liquid entry pressure value. The anti‐wetting property of the vacuum sintered membranes was further evaluated by vacuum membrane distillation process, and ensured the superior wetting resistance of the vacuum sintered PTFE membranes.
Optimization of printing parameters for improvement of mechanical and thermal performances of 3D printed poly(ether ether ketone) parts
Authors: El Magri Anouar , El Mabrouk Khalil , Vaudreuil Sébastien , Chibane Hicham , Touhami Mohamed Ebn
Published: February 2020

Many processing parameters can be adjusted to optimize the fused filament fabrication (FFF) process, a popular and widely used additive manufacturing techniques for plastic materials. Among those easily adjusted parameters are the nozzle temperature, printing speed, raster orientation, and layer thicknesses. Using poly(ether ether ketone) (PEEK) as the base material, a design of experiments analysis was performed on the main FFF parameters. A response surface methodology was applied to analyze the results and to maximize the output responses. Results have shown that the nozzle temperature is the most influential parameter on tensile properties and the crystallinity degree of printed PEEK by FFF process. Parts produced with optimized FFF parameters were then subjected to an annealing treatment to induce a relaxation of residual stress and to enhance crystallinity. The best properties for 3D printed PEEK parts were achieved with annealed parts prepared at 400°C with a printing speed of 30 mm/s, 0.15 mm layer thickness and raster orientation of [0°/15°/−15°]. The resulting parts have mechanical properties comparable to those of injected PEEK.
Polycalin is involved in the toxicity and resistance to Cry1Ac toxin in Helicoverpa armigera (Hübner)
Authors: Wang Bingjie , Wei Jizhen , Wang Yanan , Chen Lin , Liang Gemei
Published: February 2020

Polycalin has been confirmed as a binding protein of the Cry toxins in a few Lepidoptera insects, but its function in the action mechanism of Cry1Ac and whether it is involved in resistance evolution are still unclear. In this study, Ligand blot and enzyme‐linked immunosorbent assays showed that Helicoverpa armigera polycalin could specifically interact with Cry1Ac with a high affinity (Kd = 118.80 nM). Importantly, antisera blocking polycalin in H. armigera larvae decreased the toxicity of Cry1Ac by 31.84%. Furthermore, the relative gene and protein expressions were lower in Cry1Ac‐resistant strain (LF60) than that in Cry1Ac‐susceptible strain (LF). These findings indicated that H. armigera polycalin was a possible receptor of Cry1Ac and may be contributed to the resistance to Cry1Ac.
Advanced Metering Infrastructure: Reducing Water Loss, Improving Security, and Enhancing Resiliency
Authors: Mix Nelson , Lai Alan , Thompson Kenneth , Seachrist Steven C.
Published: February 2020

Key Takeaways

A pilot study was conducted to understand the use of advanced metering infrastructure in a neighborhood northeast of Atlanta, Ga.

The dashboard system displayed locations of flows and pressures as well as alerts that the team flagged for further investigation.

The usage and pressure data from the pilot project allowed detection and remediation of leaks on both sides of the meter.
An Investigation of Titanium/Silicon Oxide‐CNTs Anode Material for Lithium‐Ion Batteries
Authors: Zhang Wenshan , Li Wensheng , Zhou Xiaoping
Published: February 2020

Discovering a high‐performance (high rate capability, high specific capacity, and good stability) anode material for automobile battery applications is a great challenge. A titanium/silicon oxide‐CNTs (TimSinOl‐CNTs) is synthesized and tested as anode material for lithium‐ion batteries. High specific capacity (278 mAhg−1 at 100 mA g−1), high rate capability (156 mAh g−1 at 4000 mA g−1), and good stability (maintains 278 mAhg−1 after 200 cycles) are reached over TimSinOl‐CNTs. The as‐synthesized TimSinOl‐CNTs has a particle structure that TimSinOl encapsulates CNTs with CNTs ends stretching out of the particles. In the TimSinOl phase, the TiO2 crystal seeds are formed and encapsulated in amorphous SiOy boundaries, which have sub‐nano pores. The high performance properties of TimSinOl‐CNTs could come from the synergetic combination of (1) the excellent electronic conductivity of CNTs and the amorphous carbon in TimSinOl‐CNTs, (2) the high Li+ intaking capability of the TiO2 crystal seeds, (3) the high electrochemical activity of SiOy, (4) the high Li+ insertion/extraction kinetics in the small TiO2 crystal seeds and the amorphous SiOy with sub‐nano pores, and (5) the high volume change tolerance offered by the CNTs binder and the amorphous SiOy.
Arginine‐derived carbon nanoparticles for determination of Cr(VI) in water samples
Authors: Yahyazadeh Ehsan , Shemirani Farzaneh
Published: February 2020

Hexavalent chromium, Cr(VI), is a toxic and carcinogenic ion that poses significant risks toward human health and the environment. Due to its extensive industrial use and high water solubility, Cr(VI) can easily contaminate drinking water sources. Therefore, it is essential to develop methods to detect Cr(VI) in water samples. Recently, carbon quantum dots – being biocompatible, easy to synthesize, and cost‐effective fluorophores – have been successfully applied for the determination of different heavy metal ions. In this study, arginine‐derived carbon nanoparticles were synthesized using a solvent‐free one‐pot thermal method. These carbon nanoparticles were characterized using transmission electron microscopy, dynamic light scattering analysis, infrared spectroscopy, ultraviolet–visible (UV–vis) light spectroscopy, fluorescence spectroscopy, and CHNO elemental analysis before being used to design a sensor for Cr(VI). The sensor's signal was optimized and the arginine‐derived carbon nanoparticle‐based Cr(VI) determination method was shown to have a limit of detection of 18 nM, a limit of quantification of 60 nM, and a linear response range of 0.06–100 μM. The sensor's selectivity toward Cr(VI) was studied and a potential interfering ion was identified and dealt with. Finally, the sensor was successfully applied for the determination of Cr(VI) in tap water and mineral water samples.
Enantiomeric separation of six beta‐adrenergic blockers on Chiralpak IB column and identification of chiral recognition mechanisms by molecular docking technique
Authors: Li Meng , Jiang Zhen , Di Xin , Song Yongbo
Published: February 2020

Enantiomeric separation of six β‐adrenergic blockers was systematically studied for the first time on a polysaccharide‐based chiral stationary phase, i.e. Chiralpak IB, under the normal‐phase mode. The effect of alcohol modifiers, alcohol content and basic additive on enantiomeric separation was evaluated and optimized. Under the optimal conditions, the enantiomers of atenolol, bevantolol, cartelol, esmolol, metoprolol and propranolol were all baseline resolved with resolutions of 1.50, 8.56, 2.05, 2.11, 3.56 and 4.02, respectively. Additionally, molecular docking was tested to explain chiral recognition mechanisms of this set of the drug enantiomers on Chiralpak IB. The details of the various interactions affecting enantiomeric separation were confirmed from the molecular level and the modeling data were in agreement with the chromatographic results concerning the enantioselectivity.
Chromatographic determination of sulfasalazine and its active metabolites: greenness assessment and application to spiked human plasma
Authors: Abdelrahman Maha M. , Habib Neven M. , Emam Aml A. , Mahmoud Hamada M. , Abdelwhab Nada S.
Published: February 2020

Green TLC‐densitometric and RP‐HPLC methods were developed and validated for the determination of the active prodrug sulfasalazine (SZ), its active metabolite mesalazine (MZ) and the major active metabolite of mesalazine, N‐acetyl‐5‐aminosalicylic acid (AS). In the developed TLC‐densitometric method, chromatographic separation was carried out on TLC silica gel plates 60 F254 using a developing system consisting of ethyl acetate–methanol–ammonia solution 33% (8:2.5:0.3, by volume) and then scanning the separated bands at 215 nm using hydrochlorothiazide as an internal standard with linearity ranges of 0.4–3, 0.4–2.4 and 0.3–2 for SZ, MZ and AS, respectively. The developed RP‐HPLC method depended on chromatographic separation using a C18 column with a solvent mixture of methanol–aqueous acetic acid solution (pH 5) as a mobile phase with gradient elution mode and UV scanning at 243 nm using pyrazinamide as internal standard with linearity ranges of 5–50, 5–40, and 3–20 for SZ, MZ and AS, respectively. US Food and Drug Administration guidelines were followed during validation of the methods. The greenness of the developed methods was estimated using the greenness profile and the Eco‐Scale approach. Both methods passed the four quadrants of the greenness profile and had Eco‐Scale score ˃75, thus they were considered to be green according to these approaches.
Characterization of three‐dimensional rat central nervous system culture maturation, with applications to monitor cholinergic integrity
Authors: Andersen Parker L. , Vermette Patrick , Khalil Abdelouahed , Witkowski Jacek M. , Fülöp Tamas
Published: February 2020

Studying age‐related neuropathologies in vitro requires a three‐dimensional (3D) culture system presenting mature phenotypes. In this study, we aimed to determine whether aged reaggregate cultures physiologically represent mature brain tissue. Results support that embryo‐derived rat central nervous system (CNS) reaggregate cultures develop into mature‐like tissues, comparable to in vivo maturation, including the following characteristics: (a) progressive reduction in cell proliferation (reduced anti‐Ki‐67 immunoreactivity), (b) progressive restriction of long neurite growth potential (as explant cultures), and (c) increased and sustained synaptic enzyme (acetylcholine esterase, AChE) activity. The acquisition of mature‐like reaggregate cultures has allowed us to pursue the hypothesis that the physiological integrity of 3D CNS cultures may be monitored by synaptic enzyme activity. To assess this hypothesis, mature‐like reaggregates were exposed to H2O2, glutamate, or amyloid β(1–42); each resulted in diminished AChE activity. H2O2 exposure resulted in nuclear fragmentation. Glutamate and amyloid β(1–42) exposure resulted in acetylcholine content reduction. Simultaneous reduction of AChE activity and acetylcholine content verified diminished cholinergic integrity. This scheme exploiting synapse enzyme activity of mature‐like 3D CNS tissue is therefore applicable to age‐related neuropathology research including in vitro screening of conditions potentially affecting synapse integrity, including the promotion of dementia.
Variations of the celiac trunk investigated by multidetector computed tomography: Systematic review and meta‐analysis with clinical correlations
Authors: Whitley Adam , Oliverius Martin , Kocián Petr , Havlůj Lukáš , Gürlich Robert , Kachlík David
Published: February 2020

In recent years multidetector computed tomography (MDCT) has been used to investigate vascular anatomy for scientific and diagnostic purposes. These studies allow for much larger sample sizes than traditional cadaveric studies. The aim of this research was to perform a systematic review and meta‐analysis on studies investigating the variations of the celiac trunk using MDCT. Major medical databases were used to find studies investigating celiac trunk anatomy using MDCT. Extracted information included demographic details, number of normal celiac trunks, and number of each variant celiac trunk. Using a random effects meta‐analysis the pooled prevalence of each variation was calculated. A total of 36 studies from 14 countries and four continents were included in the meta‐analysis. The total number of subjects included was 17,391. The total prevalence of variant celiac trunks was 10.85%. The different types of celiac trunk variations with their prevalences were: gastrosplenic trunk (3.46%), hepatosplenic trunk (3.88%), hepatogastric trunk (0.24%), absent celiac trunk (0.28%), celiacomesenteric trunk (0.46%), hepatosplenomesenteric trunk (0.26%), gastrosplenomesenteric trunk (0.07%), and celiacomesenteric anastomosis (0.09%). A total of 61 cases (0.19%) were either not described or not described adequately to be included in our classification. Major variations of the celiac trunk are not uncommon and should be anticipated before radiological and surgical interventions. Knowledge of celiac trunk anatomy is important in hepatopancreatobiliary surgery, transplantology, and interventional radiology.
Teaching spread spectrum in the course Telecommunication Systems using Octave
Authors: Čisar Petar , Odry Peter , Maravić Čisar Sanja , Stankov Gordana
Published: February 2020

Spread spectrum is a technique used for transmitting telecommunications signals. This topic is relatively complex and can be challenging for students. Thus, programming language Octave has been introduced in the course curriculum of Telecommunication Systems as one of the powerful tools that aid in student understanding of the spread‐spectrum principles. The purpose of this paper is to elaborate on the teaching method of spread‐spectrum technique and its application in telecommunications, with the aim to make this topic understandable to students. The participants of the experiment were fifth‐semester electrical engineering students (N = 86) at a college of applied sciences. To test the previous knowledge of students needed to understand the theory of spread spectrum, a pretest was carried out which refers to general terms from the fundamentals of telecommunications. With the aim to deeper apprehend the necessary theory from this area, the students had to solve examples from engineering practice using open source software Octave, as well as computational tasks, regarding both methods in spread‐spectrum technology. It has been shown that thanks to the visualization of appropriate material, students of the experimental group understood in more detail the method of generating spread‐spectrum signals and the influence of individual parameters on partial signals, in relation to students who did not have the opportunity to use Octave. The results of the research lead us to conclude that software like Octave should be included in courses like Telecommunication Systems as a supplement to the traditional teaching and learning methods.
Mesenchymal stromal cell‐derived extracellular vesicles as cell‐free biologics for the ex vivo expansion of hematopoietic stem cells
Authors: Budgude Pallavi , Kale Vaijayanti , Vaidya Anuradha
Published: February 2020

Hematopoietic stem cell transplantation (HSCT) is the ultimate choice of treatment for patients with hematological diseases and cancer. The success of HSCT is critically dependent on the number and engraftment efficiency of the transplanted donor hematopoietic stem cells (HSCs). Various studies show that bone marrow‐derived mesenchymal stromal cells (MSCs) support hematopoiesis and also promote ex vivo expansion of HSCs. MSCs exert their therapeutic effect through paracrine activity, partially mediated through extracellular vesicles (EVs). Although the physiological function of EVs is not fully understood, inspiring findings indicate that MSC‐derived EVs can reiterate the hematopoiesis, supporting the ability of MSCs by transferring their cargo containing proteins, lipids, and nucleic acids to the HSCs. The activation state of the MSCs or the signaling mechanism that prevails in them also defines the composition of their EVs, thereby influencing the fate of HSCs. Modulating or preconditioning MSCs to achieve a specific composition of the EV cargo for the ex vivo expansion of HSCs is, therefore, a promising strategy that can overcome several challenges associated with the use of naïve/unprimed MSCs. This review aims to speculate upon the potential role of preconditioned/primed MSC‐derived EVs as “cell‐free biologics,” as a novel strategy for expanding HSCs in vitro.
Construction of α,α‐disubstituted α‐Amino Acid Derivatives via aza‐Morita‐Baylis‐Hillman Reactions of 2‐Aminoacrylates with Activated Olefins
Authors: Gui Hou‐Ze , Jangra Harish , Mao Ben , Wang Tian‐Yu , Yi Heng , Xu Qin , Wei Yin , Zipse Hendrik , Shi Min
Published: February 2020

A useful and convenient strategy for the synthesis of α,α‐disubstituted α‐amino acid (α‐AA) derivatives via aza‐Morita‐Baylis‐Hillman reaction of 2‐aminoacrylates with activated olefins has been developed. A variety of α‐AA derivatives containing an α‐amino tertiary center were synthesized in good to excellent yields. The kinetic profiles and calculated methyl anion affinity (MAA) values were employed to rationalize the reactivities of different Michael acceptors used in the reaction.
Efficient One‐Pot Synthesis of Higher Alcohols from Syngas Catalyzed by Iron Nitrides
Authors: Li Linge , Qing Ming , Liu Xingwu , Wang Hong , Liu Suyao , Zhang Yu , Wan Hongliu , Wen Xiaodong , Yang Yong , Li Yongwang
Published: February 2020

Efficient synthesis of higher alcohols from syngas over a single‐metal catalyst remains challenging because both active sites for CO dissociation and molecular CO adsorption are required. We report herein that iron nitrides can directly catalyze syngas to higher alcohols with high selectivity. Three iron nitride catalysts (Fe2N, Fe3N, and Fe4N) were fabricated via the nitriding of α‐Fe and their structures were confirmed by X‐ray diffraction (XRD) and Mössbauer spectroscopy (MES). Moreover, no carbides were detected even after syngas conversion for Fe2N and Fe3N catalysts, in which the N content was higher than that in Fe4N (iron nitrides transformed to Fe2C partly). The catalytic performance indicated that higher alcohols could be directly produced from syngas with remarkable selectivity (>51 % for C2+OH selectivity in total alcohols) over iron nitrides, which was tentatively ascribed to the unique electronic structure of iron nitrides, as evidenced by DFT calculation. This study proposed a novel method for the selective one‐step synthesis of higher alcohols from syngas.
Evaluation of a Microreactor for Flow Biocatalysis by Combined Theory and Experiment
Authors: Burgahn Teresa , Pietrek Philip , Dittmeyer Roland , Rabe Kersten S. , Niemeyer Christof M.
Published: February 2020

The operation of enzyme cascades in microfluidic devices is a current field of research that promises manifold applications in biocatalysis. For an optimization of flow biocatalysis systems it is desirable to model the reactor in silico in order to enable a better understanding and thus an economic optimization of the reaction systems. However, due to their high complexity, it is still difficult to simulate coupled enzyme reactions. We here describe a new model for a plug flow reactor consisting of a porous bed of compact uniform particles functionalized with an immobilized ketoreductase (Gre2) which is overflown by a mobile phase containing the enzymatic NADPH cofactor regeneration system based on glucose dehydrogenase (GDH). By studying different flow rates, lengths and layer thicknesses of the catalytic bed, we show that the synergy of experiment and mathematical modeling can optimize the space‐time yields of the reaction system.
On the avoidance of crossing of singular values in the evolving factor analysis
Authors: Neymeyr Klaus , Sawall Mathias , Rasouli Zahra , Maeder Marcel
Published: February 2020

Evolving factor analysis (EFA) investigates the evolution of the singular values of matrices formed by a series of measured spectra, typically, resulting from the spectral observation of an ongoing chemical process. In the original EFA, the logarithms of the singular values are plotted for submatrices that include an increasing number of spectra. A typical observation in these plots is that pairs of trajectories of the singular values are on a collision course, but finally, the curves seem to repel each other and then run in different directions. For parameter‐dependent square matrices, such a behaviour is known for the eigenvalues under the keyword of an avoidance of crossing. Here, we adjust the explanation of this avoidance of crossing to the curves of singular values of EFA. Further, a condition is studied that breaks this avoidance of crossing. We demonstrate that the understanding of this noncrossing allows us to design model data sets with a predictable crossing behaviour.
Enhanced Operational Durability of Thermally Activated Delayed Fluorescence‐Based Organic Light‐Emitting Diodes with a Triazine Electron Transporter
Authors: Yamaguchi Kenta , Matsushima Toshinori , Sandanayaka Atula S. D. , Homma Yoko , Uchida Naoki , Adachi Chihaya
Published: February 2020

In organic light‐emitting diodes (OLEDs) based on materials that show thermally activated delayed fluorescence (TADF), the internal quantum efficiency of 100 % can be obtained without using phosphorescence‐based organometallics that contain rare metals. Therefore, with TADF‐based emitters, it is possible to fabricate high‐performing OLEDs at a lower cost. However, compared with fluorescence‐ and phosphorescence‐based OLEDs, an understanding of degradation mechanisms in TADF‐based OLEDs is still insufficient for future commercialization. In particular, it is widely recognized that the development of electron transport materials is crucial for improving OLED characteristics, especially driving voltages and operational durability. In this study, it was demonstrated that the operational durability of TADF‐based OLEDs was greatly improved by introducing a triazine‐based material of 2,4,6‐tris(1,1′‐biphenyl‐4‐yl)‐[1,3,5]triazine (pT2T) as a hole‐blocking layer (HBL) compared with a conventional HBL material of 2,4,6‐tris(biphenyl‐3‐yl)‐[1,3,5]triazine (T2T). Several experiments were carried out to make the reasons of the improved durability clearer, and attributed the improved durability to the shift of a carrier recombination zone from the emitting layer/HBL interface and the suppressed formation of excited‐state quenchers in the pT2T HBL, because of the higher electron mobility of pT2T and the better stability of its radical anion state.
A Regulable Internal Cavity inside a Resorcinarene‐Based Hemicarcerand
Authors: Harada Kentaro , Sekiya Ryo , Haino Takeharu
Published: February 2020

Covalent organic capsules, such as carcerands and hemicarcerands, are an interesting class of molecular hosts. These container molecules have confined spaces capable of hosting small molecules, although the fact that the size of the inner cavities cannot be changed substantially limits the scope of their applications. The title covalently linked container was produced by metal‐directed dimerization of a resorcinarene‐based cavitand having four 2,2′‐bipyridyl arms on the wide rim followed by olefin metathesis at the vertices of the resulting capsule with a second‐generation Grubbs catalyst. The covalently linked bipyridyl arms permit expansion of the inner cavity by demetalation. This structural change influences the molecular recognition properties; the metal‐coordinated capsule recognizes only 4,4′‐diacetoxybiphenyl, whereas the metal‐free counterpart can encapsulate not only 4,4′‐diacetoxybiphenyl, but also 2,5‐disubstituted‐1,4‐bis(4‐acetoxyphenylethynyl)benzene, which is 9.4 Å longer than the former guest. Molecular mechanics calculations predict that the capsule expands the internal cavity to encapsulate the long guest by unfolding the folded conformation of the alkyl chains, which demonstrates the flexible and regulable nature of the cavity. Guest competition experiments show that the preferred guest can be switched by metalation and demetalation. This external‐stimuli‐responsive guest exchange can be utilized for the development of functional supramolecular systems controlling the uptake, transport, and release of chemicals.
Research into the oxidation of abietic acid–derived enone with atmospheric oxygen
Authors: Masnyk Marek , Kuśmirek Damian , Trzybiński Damian , Frelek Jadwiga
Published: February 2020

This work presents results of methyl 7‐oxoabiet‐13(14)‐en‐18‐oate (3) self‐oxidation with air‐oxygen in the presence of various bases such as triethylamine or sodium t‐butoxide. While under aerobic conditions, the use of sodium t‐butoxide as a base results in the formation of four isomeric alcohols, an addition of triethylamine into reaction medium directs the enone 3 oxidation to hydroperoxides. To clarify this base dependence and to obtain more in‐depth information about this reaction additional studies with cyclohexenone as a reference enone have been undertaken. Their results demonstrated the predisposition of abietane hydroperoxides to oxidize α,β‐unsaturated ketones to epoxides in the presence of t‐butoxide while reducing the hydroperoxide group to hydroxyl. This ability of hydroperoxides to epoxidize conjugated double bonds and confirmed by the present study intermolecular course allowed proposing a plausible mechanism for this reaction.
A multiscale absorption and transit model for oral drug delivery: Formulation and applications during fasting conditions
Authors: Kannan Ravishekar , Przekwas Andrzej
Published: February 2020

Most Food and Drug Administration (FDA)‐approved drugs are administered orally, despite the complex process of oral drug absorption that is difficult to analyze experimentally. Oral bioavailability is dependent on the drug compound as well as the physiological and anatomical states of the user. Thus, computational models have emerged to mechanistically capture and predict the oral absorption process. The current models are generally 0D compartmental models and are limited by (a) simplified physiological characteristics of the gastrointestinal tract (GIT), (b) semiempirical/analytical dissolution profiles of the tested drugs, (c) incorrect absorption for some drug BCS classes (class IIa, for example), (d) GITs size variability among population, (e) incorrectly predicting the absorption of drugs that are GIT target specific, and (f) erroneous mixing in the domain. In this study, we have developed a multiscale absorption and transit (MAT) toolkit to simulate the dissolution, transport, absorption, distribution, metabolism, and elimination of orally administered drugs in the human GIT at multiple levels. MAT was constructed by integrating the spatially accurate first‐principles driven high‐fidelity drug transport, dissolution, and absorption model in the human stomach and GIT using our recently published quasi‐3D (Q3D) framework. The process integrated the multilayer intestine physiologically based pharmacokinetics models with the whole‐body compartmental models to predict the systemic pharmacokinetics of oral drugs. The computational results showed that this multiscale tool was able to match the experimental concentration results (individual and population) better than the traditional compartmental models. Ultimately, MAT will be developed into a commercial product to meet urgent demands from pharmaceutical and biomedical industries.
Gold Nanoparticles Stabilized by Molecular Fullerenols
Authors: Kokubo Ken , Espejo Cabello Mark Kristan , Sato Nozomi , Uetake Yuta , Sakurai Hidehiro
Published: February 2020

Polyhydroxylated fullerene derivatives (fullerenols: C60(OH)12 and C60(OH)36) exhibit excellent stabilizing matrices for gold nanoparticles. Au:C60(OH)12 and Au:C60(OH)36 form hydrophilic colloids and are well dispersed in H2O, even though C60(OH)12 itself is barely dissolved in H2O. It was estimated that C60(OH)12 forms a two‐ to three‐layered structure with 3D O−H⋅⋅⋅O hydrogen‐bonding networks, surrounding approximately 3 nm‐sized Au NPs. The thus‐prepared Au:C60(OH)n colloids exhibited a high catalytic activity toward the reduction of 4‐nitrophenol to 4‐aminophenol. The short induction period as well as kinetic and thermodynamic parameters indicated the dynamic mobility of the fullerenol matrix and the hydrophobic nature of the interface between the Au surface and the matrix.
A sharp‐selective micro strip triplexer with hairpin resonators for long‐term evolution (LTE)
Authors: Mohammadi Pejman , Ebadzadeh Roghaye , Mohammadifar Maryam
Published: February 2020

A compact size planar micro strip triplexer for long‐term evolution (LTE) is presented. The triplexer consists of three hairpin band pass filters and a T‐shaped micro strip line. T‐shaped microstrip line has been used as input signal splitting structure and hairpin filters bring sharp selectivity. Input impedance matching of the structure carried out with three metalized vias in the middle of the filters. The central pass band frequencies (0.9, 1.17, and 1.5 GHz) are selected according to LTE frequency bands. The pass band of the filters include 0.88 to 0.91, 1.16 to 1.21, and 1.47 to 1.53 GHz. Isolation among the output channels are better than 40 dB. The measurement results verify the design process satisfactorily. The proposed triplexer can be used in BTS antenna for enabling more than one transmitter on a single antenna.
Dyslexia in a consistent orthography: Evidence from reading‐level match design
Authors: Parrila Rauno , Georgiou George K. , Papadopoulos Timothy C.
Published: February 2020

Studies in consistent orthographies using reading‐level (RL) match design have produced conflicting results, possibly because of problems with general ability and RL matching in many studies. We matched the participants on both verbal and nonverbal ability and on reading tasks with no ceiling effects and compared the performance of Grades 4 and 6 Greek‐speaking children with dyslexia to those of chronological age (CA) and RL matched control groups across a variety of tasks associated with dyslexia (phonological awareness, rapid naming, phonological memory, and orthographic processing). The results showed that although both Grade 4 and Grade 6 dyslexics performed poorer than the CA groups in most tasks, they did not perform poorer than the RL group in any of the tasks included. We conclude with a discussion of the theoretical ramifications of the results and the appropriateness of the RL match design in studying dyslexia in consistent orthographies.
Cocreating research priorities for anorexia nervosa: The Canadian Eating Disorder Priority Setting Partnership
Authors: Obeid Nicole , McVey Gail , Seale Emily , Preskow Wendy , Norris Mark L.
Published: February 2020

Objective

The Canadian Eating Disorder Priority Setting Partnership was established to identify and prioritize the top 10 research priorities for females, 15 years or older, with anorexia nervosa, by incorporating equal input from those with lived experience, families, and healthcare professionals.

Method

This project, which closely followed the James Lind Alliance guidelines, solicited research priorities from the Canadian eating disorder community by means of a five‐step process including use of a survey, response collation, literature checking, interim ranking survey, and in‐person prioritization workshop.

Results

The initial survey elicited 897 priorities from 147 individuals, with almost equal representation from all three stakeholder groups. From this, 603 responses aligned with the project objectives and were collapsed into 71 broader indicative questions. Based on available systematic reviews, 18 indicative questions were removed as they were considered answered by existing literature while 8 indicative questions were added from the recommendations of the reviews. In total, 61 indicative questions were ranked in an interim ranking survey, where 21 questions were prioritized as important by at least 20% of respondents. As a final step, 28 individuals from across Canada attended the prioritization workshop to coestablish the top 10 research priorities.

Discussion

Top priorities were related to treatment gaps and the need for more surveillance data. This systematic methodology allowed for a transparent and collaborative approach to identifying current priorities from both the service user and provider perspective. Wide dissemination is anticipated to promote work that is of high relevance to patients, families, and clinicians.
Behavioral modeling of permanent magnet synchronous motor fed by PWM inverters considering iron losses due to carrier harmonics
Authors: Shutta Yusaku , Takahashi Yasuhito , Fujiwara Koji
Published: February 2020

This paper proposes a new method for behavioral modeling of a permanent magnet synchronous motor (PMSM) fed by a PWM inverter considering the iron losses due to carrier harmonics. In the proposed method, an inductance is connected in series with an iron loss resistance in the equivalent circuit of the PMSM to suppress the harmonic current due to carrier harmonics. The effectiveness of the proposed method is investigated by comparing the numerical results of iron losses of the PMSM obtained using a finite‐element method and the newly derived equivalent circuit.
CD8+ T cells mediate ultraviolet A‐induced immunomodulation in a model of extracorporeal photochemotherapy
Authors: Hequet Olivier , Nosbaum Audrey , Guironnet‐Paquet Aurélie , Blasco Elisabeth , Nicolas‐Virelizier Emmanuelle , Griffith Thomas S. , Rigal Dominique , Cognasse Fabrice , Nicolas Jean‐François , Vocanson Marc
Published: February 2020

Extracorporeal photochemotherapy (ECP) that takes advantage of the immunomodulatory effects of UV light has been extensively used for many years for the treatment of several T cell–mediated diseases, including graft‐versus‐host disease (GvHD) and systemic scleroderma. Immune mechanisms that lead to the establishment of T cell tolerance in ECP‐treated patients remain poorly known. In this study, we have tested the effect of UV/psoralen‐treated BM‐derived dendritic cells, referred to as ECP‐BMDCs on the outcome of an antigen‐specific T cell‐mediated reaction, that is, contact hypersensitivity (CHS), which is mediated by CD8+ effector T cells (CD8+Teff). The intravenous (i.v.) injection of antigen‐pulsed ECP‐BMDCs in recipient C57BL/6 mice induced specific CD8+ T cells endowed with immunomodulatory properties (referred to as CD8+TECP), which prevented the priming of CD8+Teff and the development of CHS, independently of conventional CD4+ regulatory T cells. CD8+TECP mediated tolerance by inhibiting the migration and functions of skin DC and subsequently the priming of CD8+Teff. CD8+TECP displayed none of the phenotypes of the usual CD8+T regulatory cells described so far. Our results reveal an underestimated participation of CD8+ T cells to ECP‐induced immunomodulation that could explain the therapeutic effects of ECP in T cell‐mediated diseases.
Rhodium(III)‐Catalyzed Alkynylation of 4‐Arylphthalazin‐1(2H)‐one Scaffolds via C‐H Bond Activation
Authors: Du Xuxin , Hou Hongcen , Zhao Yongli , Sheng Shouri , Chen Junmin
Published: February 2020

Selective C–H bond alkynylation toward modular access to material and pharmaceutical molecules is of great desire in modern organic synthesis. Disclosed herein is rhodium(III)‐catalyzed selective C–H bond mono‐/bialkynylation of 4‐aryl phthalazin‐1(2H)‐one was developed. The silver salt AgSbF6 are demonstrated to play a vital role in promoting the bialkynylation reactions. The present alkynylation strategy is simple, efficient, and features high functional group tolerance and broad substrate scope under an air atmosphere. Additionally, 6‐aryl pyridazin‐3(2H)‐one scaffold is amenable to the selective monoalkynylation and sequential bialkynylation, respectively.
Boron‐Promoted Ether Interchange Reaction: Synthesis of Alkyl Nitroaromatic Ethers from Methoxynitroarenes
Authors: Liu Zhenwei , Luan Nannan , Lu Hongtao , Liang Apeng , Li Jingya , Zou Dapeng , Wu Yangjie , Wu Yusheng
Published: February 2020

The first protocol for boron‐promoted ether interchange reaction of methoxynitroarenes was described. A series of methoxynitroarenes and alcohols, including primary, secondary, as well as tertiary alcohols were reacted smoothly in moderate to good yields under the optimized reaction conditions. This protocol constitutes an operationally simple and scalable strategy for the synthesis of alkyl nitroaromatic ethers. Moreover, the new reactivity of boron reagents was discovered.
(2R,3S)‐3,4,4,4‐Tetrafluorovaline: A Fluorinated Bioisostere of Isoleucine
Authors: Brewitz Lennart , Noda Hidetoshi , Kumagai Naoya , Shibasaki Masakatsu
Published: February 2020

The synthesis of (2R,3S)‐3,4,4,4‐tetrafluorovaline, a fluorinated derivative of the canonical α‐amino acid l‐valine, is reported for the first time. A highly enantio‐ and diastereoselective direct catalytic asymmetric Mannich‐type reaction was applied as the key C–C bond‐forming step to afford gram quantities of a central synthetic intermediate. The conformation of the novel fluorinated α‐amino acid was analyzed by X‐ray crystallography, NMR spectroscopy, and computational methods, which, together with its calculated and experimental physicochemical properties, indicated that the fluorinated valine is a bioisostere of l‐isoleucine.
Close to me: The importance of closeness versus superficiality in explaining the positive‐negative contact asymmetry
Authors: Fuochi Giulia , Voci Alberto , Boin Jessica , Hewstone Miles
Published: February 2020

The evidence for differential effects of positive and negative intergroup contact on prejudice is mixed. We propose that the closeness of the relationships respondents have with contact partners can explain inconsistencies in previous findings. In three studies (total N = 953), we tested the associations between positive intimate, negative intimate, positive superficial, and negative superficial contact and attitudes toward different outgroups (immigrants and gay people). We hypothesized that: (H1) the effect of positive contact would be maximized in intimate interactions; (H2) the effect of negative contact would be maximized in superficial interactions; (H3) positive intimate and negative superficial contact would have similar power in predicting attitudes. Results always supported H1, and supported H2 and H3 only with immigrants. Findings held also when controlling for category salience and agreeableness, but not for social dominance orientation, which instead strengthened the effect of negative superficial contact. Overall, findings clarify the positive–negative contact asymmetry.
RETRACTED: Copper Oxide Nanoparticles with Graphitic Carbon Nitride for Ultrasensitive Photoelectrochemical Aptasensor of Bisphenol A
Authors: Yang Liqin , Zhao Zhiju , Hu Jie , Wang Huibin , Dong Junfang , Wan Xiang , Cai Zhenyu , Li Mengying
Published: February 2020

In this work, g‐C3N4, CuO and g‐C3N4/CuO−X (where × can be 3, 6, or 9) were synthesized through hydrothermal and calcination methods and used to fabricate photoelectrochemical (PEC) aptasensor for detection of bisphenol A (BPA). CuO nanoparticles covered with g‐C3N4 were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The aptasensor based on g‐C3N4/CuO‐6 possessed high PEC activity due to its good conductivity and low electron recombination rate. PEC experiments demonstrate that the aptasensor based on g‐C3N4/CuO‐6 exhibits a broad linear range towards BPA from 0.02–10 ng L−1 and 50–1200 ng L−1 and reveals superior stability, selectivity and repeatability. Thus, g‐C3N4/CuO‐6 composite is a promising material for the determination of BPA in PEC field and has commercially viable.
Porous Molybdenum Carbide Nanostructured Catalyst toward Highly Sensitive Biomimetic Sensing of H2O2
Authors: Li Juan , Tang Chun , Liang Taotao , Tang Chuyue , Lv Xiaohui , Tang Kanglai , Li Chang Ming
Published: February 2020

There are great challenges to fabricate a highly selective and sensitive enzyme‐free biomimetic sensor. Herein for the first time a unique nanostructure of porous molybdenum carbide impregnated in N‐doped carbon (p‐Mo2C/NC) is synthesized by using SiO2 nanocrystals‐templating method and is further used as an enzyme‐free electrochemical biosensor toward highly selective, sensitive detection of H2O2, of which the limit of detection, dynamic detection range and sensitivity accomplish as 0.22 μM, 0.05–4.5 mM and 577.14 μA mM−1 cm−2, respectively, and are much superior to the non‐porous molybdenum carbide impregnated in N‐doped carbon (Mo2C/NC). The sensor is also used to monitor H2O2 released from A549 living cells. This work holds a great promise to be used to monitor the presence of H2O2 in biological research while offering an important knowledge to design a highly selective and sensitive biomimetic sensor by synthesizing a porous catalyst to greatly improve the reaction surface area rather than conventionally only relying on dispersing the catalyst material into porous carbon substrate.
Complex three‐dimensional microparticles from microfluidic lithography
Authors: Tian Ye , Wang Liqiu
Published: February 2020

Complex 3D microparticle, as an emerging and attractive field, has attracted more and more attention due to its versatile morphologies and broad range of applications. In this review, we provide an overall recent progress in 3D microparticles fabricated by microfluidic lithography. This review will focus on the synthesis mechanisms, synthesis process, the resultant 3D microparticles, and their applications. Finally, we will look into the future trends in complex 3D microparticles. This review will be beneficial for researchers in numerous fields, including functional materials, sensors, encryption, and biomedical engineering.
The dilemma of altitudinal shifts: caught between high temperature and low oxygen
Authors: Jacobsen Dean
Published: February 2020

Global warming is expected to drive species toward higher altitudes. Indeed, most documented range shifts are upward, but observed shifts are often far from model predictions, and even downward shifts are common. Can such counterintuitive observations be explained? Metabolic oxygen demand rises with temperature in ectothermic animals, but levels of metabolic sensitivity to temperature increases (Q10) vary among species. Oxygen availability also decreases with altitude, which potentially interferes with the ability of organisms to track their thermal niches upward. Here, I introduce the “metabolic oxygen‐driven altitude shift” (MODAS) framework, which accounts for an overlooked cause of interspecies variation in range shifts. Upward shifts should always occur if it is most important for the species to conserve its pre‐warming temperature. In contrast, if conserving the oxygen demand–supply balance has priority, then downward shifts should occur for species that are less sensitive to temperature increases (low Q10), while excessive upward shifts to lower than pre‐warming temperatures should occur at high Q10.
Exit strategies for wildlife conservation: why they are rare and why every institution needs one
Authors: Ruiz‐Miranda Carlos R , Vilchis L Ignacio , Swaisgood Ronald R
Published: February 2020

Exit strategies – plans to end involvement in a project once selected criteria have been reached – are rare in conservation planning but can play a vital role in the conservation planning process; such strategies also prepare the institution, its staff, its partners, and a wider group of stakeholders for eventual success or failure and signal when it is time to move on. Exit strategies may indicate that the project has been terminated but may also signal success, or that project leadership has transitioned to another, more appropriate entity. We address why exit strategies are uncommon in conservation, why they are essential, what determines when to transition or leave, and how to plan for circumstances afterwards. A good exit strategy addresses financial and legal liabilities to employees, publication of results, and ownership of data, among other things. A comprehensive, thoughtful strategy can lead to “beautiful exits” that minimize negative consequences to the project.
An improved diffuse interface method for three‐dimensional multiphase flows with complex interface deformation
Authors: Zhang Tongwei , Wu Jie , Lin Xingjian
Published: February 2020

An improved diffuse interface (DI) method is proposed for accurately capturing complex interface deformation in simulations of three‐dimensional (3D) multiphase flows. In original DI methods, the unphysical phenomenon of interface thickening or blurring can affect the accuracy of numerical simulations, especially for flows with large density ratio and high Reynolds number. To remove this drawback, in this article, an interface‐compression term is introduced into the Cahn‐Hilliard equation to suppress the interface dispersion. The additional term only takes effect in the interface region and works normal to the interface. The difference of the current method from the previous work is that the compression rate can be adjusted synchronously according to the magnitude of local vorticity, which is strongly correlated to the interface dispersion and changes with the computational time and interface position. Numerical validations of the proposed method are implemented by simulating problems of Laplace law, Rayleigh‐Taylor instability, bubble rising in a channel, and binary droplet collision. The obtained results agree well with the analytical solutions and published data. The numerical results show that the phenomenon of interface dispersion is suppressed effectively and the tiny interfacial structures in flow field can be captured accurately.