bluuebunny/crossref_metadata_2025 huggingface dataset:
Palladium‐Catalyzed Three‐Component Reactions for the Synthesis of Norbornane‐Fused Indanes
Authors: Ji Xiaoming , Gu Yichao , Cheng Cang , Wu Zhuo , Zhang Yanghui
Published: January 2020

Two methods for the synthesis of norbornane‐fused indanes via palladium‐catalyzed three‐component reactions of iodoarenes, norbornenes, and CH2Br2 or α‐diazoesters have been developed. In the reactions, three C−C bonds were constructed and a wide range of norbornane‐fused indanes could be synthesized. The reactions with α‐diazoesters proceeded with a high degree of diastereoselectivity and indanes bearing an all‐carbon quaternary center were formed. The products obtained in the reactions of 1,4‐dihydro‐1,4‐epoxynaphthalene can be converted to fluorenes, providing an alternative way to access fluorene derivatives.

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Photoredox‐Catalyzed Redox‐Neutral Minisci C−H Formylation of N‐Heteroarenes
Authors: Dong Jianyang , Wang Xiaochen , Song Hongjian , Liu Yuxiu , Wang Qingmin
Published: January 2020

We report a protocol for redox‐neutral Minisci C−H formylation of N‐heteroarenes using 1,3‐dioxoisoindolin‐2‐yl 2,2‐diethoxyacetate as a formyl equivalent at room temperature. This scalable benchtop protocol offers a distinct advantage over traditional reductive carbonylation and Minisci C−H formylation methods in not requiring the use of carbon monoxide, pressurized gas, a stoichiometric reductant, or a stoichiometric oxidant.

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Lysyl Oxidase Like‐2 (LOXL2): An Emerging Oncology Target
Authors: Chopra Vriddhi , Sangarappillai Ruth M. , Romero‐Canelón Isolda , Jones Alan M.
Published: January 2020

Lysyl oxidase‐like 2 (LOXL2) is an emerging drug target against metastatic disease owing to its role in the upregulation of key processes including epithelial‐mesenchymal transition (EMT) and invasion. Recent activity in the field of small molecule LOXL2 inhibitor development by pharmaceutical and academic laboratories has renewed interest in targeting LOXL2. Herein, 1) the viability of LOXL2 as a drug target for the treatment of metastatic disease through an investigation of its biological actions is determined; 2) the pitfalls of an antibody approach are considered; and 3) the small molecule approaches emerging in the scientific and patent literature are reviewed.

This review identifies that LOXL2 is localized and active intracellularly and extracellularly in invasive cancer cells. LOXL2 has been implicated in a number of established signaling pathways involved in tumor progression, further highlighting its appeal as a target in metastatic disease.

Previously, limited chemical inhibitors have been developed; however, their selectivity profile for the LOX family has proven controversial. Antibodies, such as simtuzumab, have been developed selectively against LOXL2. Simtuzumab, in particular, progresses into phase II trials but it was ultimately terminated. The small molecule inhibitors of LOXL2 are summarized, some of which are now in the early stages of clinical trials.
Highly Sensitive and Stretchable Carbon Nanotube/Fluoroelastomer Nanocomposite with a Double‐Percolated Network for Wearable Electronics
Authors: Shajari Shaghayegh , Mahmoodi Mehdi , Rajabian Mahmoud , Karan Kunal , Sundararaj Uttandaraman , Sudak Les Jozef
Published: January 2020

A smart stretchable material is developed from a composite of carbon nanotube (CNT) and fluoroelastomer (FKM), which is fabricated via an internal melt‐mixer method. A unique, double‐percolated, electrically conductive network is observed with ultralow percolation thresholds of 0.45 phr and 1.40 phr CNT. This provides the CNT/FKM nanocomposites with a wide range of strain sensitivity. Thin‐film nanocomposites at the first plateau of conductivity show an ultrahigh sensitivity with a gauge factor (GF) of 1010 at 23% strain for 0.6 phr and of 6750 at 34% strain for 1 phr. At the second plateau of conductivity, 1.5 phr nanocomposite corresponds to higher levels of strain of 78% strain with ultrahigh GF of more than 4 × 104 and 2 phr nanocomposite to almost 100% strain with GF of 1.3 × 105. The CNT/FKM nanocomposites possess a high elongation at break of 430% and up to 232% strain sensitivity. The unique distribution of CNTs in the polar fluoroelastomer FKM facilitates simultaneous high sensitivity and high stretchability, and improved mechanical strength over reported polymer‐based nanocomposite stretchable sensors. The novel, stretchable CNT‐based FKM conductors have great potential for wearable electronics such as stretchable sensors, stretchable light‐emitting diodes (LEDs), and human motion monitoring.
Mixed Molecular Electronics: Tunneling Behaviors and Applications of Mixed Self‐Assembled Monolayers
Authors: Kong Gyu Don , Byeon Seo Eun , Park Sohyun , Song Hyunsun , Kim Seo‐Yeon , Yoon Hyo Jae
Published: January 2020

Molecular electronics promise electronic devices that are miniaturized to molecular and atomic levels. Despite significant efforts made towards understanding and improving the electronic functions of devices based on homogeneous molecular systems, the roles, effects, and importance of molecular‐level dilution and mixing in active components for device performance have only recently begun to be understood. Recent advances in molecular electronics based on heterogeneous active components, defined as mixed molecular electronics, are reviewed, with a particular focus on molecular tunnel junctions containing mixed self‐assembled monolayers (SAMs). Through a stepwise approach, the following is provided: a) a summary of the unique (supra)molecular and electronic structural features of mixed SAMs compared to homogeneous SAMs, b) a discussion on fundamental understanding of charge transport across mixed molecular systems, c) a comprehensive summary of functional mixed‐molecular tunneling devices, and d) perspectives on the future direction of mixed molecular electronics.
Efficient Photocatalytic Nitrogen Fixation over Cuδ+‐Modified Defective ZnAl‐Layered Double Hydroxide Nanosheets
Authors: Zhang Shuai , Zhao Yunxuan , Shi Run , Zhou Chao , Waterhouse Geoffrey I. N. , Wu Li‐Zhu , Tung Chen‐Ho , Zhang Tierui
Published: January 2020

The photocatalytic reduction of nitrogen (N2) with water (H2O) as the reducing agent holds great promise as a sustainable future technology for the synthesis of ammonia (NH3). Herein, the effect of oxygen vacancies and electron‐rich Cuδ+on the performance of zinc‐aluminium layered double hydroxide (ZnAl‐LDH) nanosheet photocatalysts for N2reduction to NH3under UV–vis excitation is systematically explored. Results show that a 0.5%‐ZnAl‐LDH nanosheet photocatalyst (containing 0.5 mol% Cu by metal basis) affords a remarkable NH3production rate of 110 µmol g−1h−1and excellent stability in pure water. The X‐ray absorption spectroscopy, electron paramagnetic resonance, and density functional theory calculations reveal that Cu addition imparts oxygen vacancies and coordinatively unsaturated Cuδ+(δ < 2) with electron‐rich property in the ZnAl‐LDH nanosheets, both of which readily contribute to efficient separation and transfer of photogenerated electrons and holes and promote N2adsorption, thereby both activating N2and facilitating its multielectrons reduction to NH3.
Suppressor capacity of iron nanoparticles biosynthesized using Salvia chloroleuca leaf aqueous extract on methadone‐induced cell death in PC12: Formulation a new drug from relationship between the nanobiotechnology and neurology sciences
Authors: Ahmeda Ahmad , Zangeneh Mohammad Mahdi , Mansooridara Shirin , Malek Zahra , Zangeneh Akram
Published: January 2020

Metallic nanoparticles have gained significant attention in the area of biomedical technology. Because of its high surface area, metallic nanoparticles are being widely used in various fields including the medical and engineering sciences. One of the valuable applications of metallic nanoparticles especially copper, zinc, and iron nanoparticles is increasing the physiological function of central nervous system. Besides, Iranian people are using the Salvia chloroleuca for neuroprotective properties. In the present research, iron nanoparticles were biosynthesized by S. chloroleuca leaf aqueous extract as reducing and stabilizing agents. Also, we revealed the protective effect of FeNPs in methadone‐treated PC12 cells. FeNPs were characterized and analyzed using common nanotechnology techniques including FT‐IR, UV–Vis. spectroscopy; EDS, TEM, and FE‐SEM. TEM and FE‐SEM images revealed a uniform spherical morphology for FeNPs. In the biological part of the current study, the both treatments of FeNPs significantly (p ≤ 0.01) reduced the cell cytotoxicity and cell death index as well as increased the cell viability and cell proliferation in methadone‐treated PC12 cells. In these treatments, mitochondrial membrane potential significantly (p ≤ 0.01) increased compared to methadone‐induced PC12 cells. DPPH free radical scavenging test was did to evaluate the antioxidant potentials of FeCl3, S. chloroleuca, and FeNPs. DPPH test indicated similar antioxidant activities for S. chloroleuca, FeNPs, and butylated hydroxytoluene. In current experiment, we concluded that iron nanoparticles biosynthesized by S. chloroleuca leaf aqueous extract suppressed methadone‐induced cell death in a dose‐dependent manner in PC12 cells.
Design and identification of nano‐Mg‐[4‐methoxy phenyl‐salicylaldimine–methyl‐pyranopyrzole] Cl2 and its catalytic application on the preparation of 1‐(α‐aminoalkyl)‐2‐naphthols
Authors: Goudarziafshar Hamid , Moosavi‐Zare Ahmad Reza , Hasani Jafar
Published: January 2020

Nano‐Mg‐ [4‐methoxy phenylsalicylaldiminemethylpyranopyrazole]Cl2 (nano‐[Mg‐4MSMP]Cl2) as a nano‐Schiff base complex was prepared and fully characterized using some various techniques including fourier transform infrared spectroscopy (FT‐IR), energy‐dispersive x‐ray spectroscopy (EDS), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric analysis (DTA), mass spectroscopy (MS) and scanning electron microscopy (SEM). Nano‐[Mg‐4MSMP]Cl2 was successfully used as an efficient catalyst for the preparation of some 1‐(α‐aminoalkyl) ‐2 ‐naphthols.
Metformin Containing Nickel (II) Complexes: Synthesis, Structural Characterization, Binding and Kinetic Interactions with BSA, Antibacterial and in‐vitro Cytotoxicity Studies
Authors: Elshami Fawzya I. , Ramadan Abd El‐Motaleb M. , Ibrahim Mohamed M. , El‐Mehasseb Ibrahim M. , Al‐Juaid Salih , Shaban Shaban Y.
Published: January 2020

In quest of antimicrobial and anticancer agents, metformin containing Ni (II) complexes, [Ni (Met)2]Cl·OH (1) and [Ni (Met)(IDA)] (2) {Met: metformin, IDA: iminodiacetic acid} were synthesized and X‐ray structure of 1 is four‐coordinate square planar geometry. Bovine serum albumin (BSA) interaction and binding studies to Met, IDA and their Ni (II) complexes were investigated and showed a strong interaction. A static quenching process was proposed at low concentrations of compounds whereas, combined quenching process was observed for 1 and 2 at higher concentrations. Kinetic stability, affinity and association constants of compounds‐BSA were studied using stopped‐flow technique and a mechanism was proposed: a fast and reversible step of BSA binding including complex formation and dissociation was proposed; for the second step, a reversible reaction was observed for 1 and 2 whereas, an irreversible reaction with Met and IDA was observed indicating that coordination with nickel ions change the interaction mechanism. Additionally, the antibacterial investigation against both Gram‐positive and Gram‐negative bacteria showed that all compounds exhibited significant activities. They also show cytotoxicity against HepG2 human liver cancer cell but the half maximal inhibitory concentration (IC50) values obtained for the cell lines were higher in comparison with cisplatin. Although Met‐BSA and IDA‐BSA are kinetically more stable than that of 1‐BSA and 2‐BSA, 1‐BSA and 2‐BSA showed better antibacterial and cytotoxic activities which is in agreement with the binding constants.
Novel NiFe/Si/Au magnetic nanocatalyst: Biogenic synthesis, efficient and reusable catalyst with enhanced visible light photocatalytic degradation and antibacterial activity
Authors: Shirzadi‐Ahodashti Mina , Ebrahimzadeh Mohammad Ali , Amiri Omid , Naghizadeh Ali , Mortazavi‐Derazkola Sobhan
Published: January 2020

The aim of this paper is to biosynthesize NiFe2O4/SiO2/Au (NiFe/Si/Au) magnetic nanocatalyst using the sonochemical method. This is the first study to synthesize this compound using this method. To obtain optimum morphology and size of products, the synthesis was performed in the presence of polyvinylpyrrolidone, maltose, glucose, and fructose as capping agents and Crataegus pentagyna leaf extract and NaBH4 as reducing agents. Vibrating‐sample magnetometer, field‐emission scanning electron microscopy, Fourier‐transform infrared, transmission electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and differential reflectance spectroscopy techniques were performed to confirm the preparation of magnetic products. The as‐synthesized magnetic samples were used to enhance the photocatalytic degradation and antibacterial activity. The NiFe/Si/Au nanocatalysts exhibited an excellent photocatalytic activity by degradation of rhodamine b, methylene blue, and erythrosine as organic contaminants under ultraviolet and visible light irradiation. The degradation curves illustrate that the degradation of anionic dyes is more than that of cationic dyes. In addition, antibacterial activity of as‐prepared nanocatalyst against seven bacterial species was investigated. Because of their antibacterial effects, as‐synthesized products show a high antibacterial activity against various bacteria. Consequently, the NiFe/Si/Au nanocatalysts with high antibacterial activity and excellent potential photocatalyst activity can be used in environmental and medical sciences for wastewater treatment.
Singular optimal control problems with recursive utilities of mean‐field type
Authors: Hao Tao , Meng Qingxin
Published: January 2020

In this paper a second‐order necessary condition for singular optimal controls with recursive utilities of mean‐field control systems is investigated. For our mean‐field singular control problem, the second‐order adjoint system is not a single mean‐field backward stochastic differential equation (BSDE), but a matrix‐valued system, which consists of three classical BSDEs. Based on this observation, a new second‐order expansion of cost functional
is proved and also the stochastic maximum principle. Our method is appropriate for a large class of mean‐field singular optimal control problems.
Beyond intervention into daily life: A systematic review of generalisation following social communication interventions for young children with autism
Authors: Carruthers Sophie , Pickles Andrew , Slonims Vicky , Howlin Patricia , Charman Tony
Published: January 2020

Researchers have generally considered autistic individuals to have difficulties generalising learned skills across novel contexts. Successful generalisation is necessary for an intervention to have benefits in everyday life beyond the original learning environment. We conducted a systematic review of randomised controlled trials of early social communication interventions for children with autism in order to explore generalisation and its measurement. We identified nine RCTs that provided evidence of initial target learning and measured generalisation, of which eight demonstrated at least some successful generalisation across people, settings, and/or activities. The findings did not support the widely reported generalisation ‘difficulties’ associated with autism. However, generalisation was not consistent across all skills within studies, and one study found no generalisation despite evidence for initial target learning within the intervention context. In general, there are few methodologically sound social communication intervention studies exploring generalisation in autism and no consensus on how it should be measured. In particular, failure to demonstrate initial learning of target skills within the intervention setting and an absence of formal mediation analyses of the hypothesised mechanisms limit current research. We outline a framework within which measurement of generalisation can be considered for use in future trials. To maximise the effectiveness of interventions, the field needs to gain a better understanding of the nature of generalisation among autistic individuals and what additional strategies may further enhance learning. Autism Res 2020, 13: 506–522. © 2020 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.

Lay Summary

It is generally considered that autistic individuals experience difficulties applying things they have learned in one context into different settings (e.g. from school to home). This is important to consider for intervention studies. Our review does not support a complete lack of generalisation but instead suggests that after early social communication intervention, autistic children can transfer some skills to new contexts. Overall, there is limited research in this area and further work is needed.
Atypical bronchus in the right lower lobe: Computed tomography‐based analysis
Authors: Ying Zhang , Kim Sung Jin , Yoo Jin Young
Published: January 2020

Introduction

The aim of this study was to define the subsuperior bronchus (B*) and reestablish the bronchial anatomy of the right lower lobe (RLL) by assessment of atypical bronchi.

Materials and Methods

Chest computed tomography (CT) scans of 500 consecutive patients were retrospectively evaluated. All CT scans were acquired with 64‐slice scanners. Atypical bronchi in the RLL were classified on the basis of running direction and shape: lateral (Lat), posterolateral (PL), posterior (Post), Lat + PL, and PL + Post. We classified an atypical bronchus in the basal segmental bronchus (BSB) stem running posteriorly or posterolaterally as B* and a para‐lateral bronchus running laterally as Para‐B8. The B* posts running posteriorly were named P1, and those running medially P2.

Results

Atypical BSB bronchi Lat, PL, and Post arose from B8, B9, and B10, respectively. All Lat + PL bronchi arose from B8 or B9, and all PL + Post from B9 or B10. When an atypical bronchus arose from one of the BSB pair, none arose from the other. Atypical bronchi forming B* and Para‐B8 arose from the stem spreading the connatural BSBs. The P2 post coexisted with another atypical stem bronchus originating from B8, 9, 10, or higher.

Conclusions

The first subsegmental bronchi of B8, B9, and B10 are Lat, PL, and Post, respectively. Lat + PL and PL + Post bronchi at the BSB level could result from fusion of an atypical bronchus during downward migration. The stem B* and Para‐B8 could result from arrested downward migration of atypical bronchi. This information is useful for RLL segmentectomy.
The clinical anatomy of accessory mandibular canal in dentistry
Authors: Ngeow Wei Cheong , Chai Wen‐Lin
Published: January 2020

The mandibular canal is a conduit that allows the inferior alveolar neurovascular bundle to transverse the mandible to supply the dentition, jawbone and soft tissue around the gingiva and the lower lip. It is not a single canal but an anatomical structure with multiple branches and variations. The branches are termed accessory, bifid or trifid canals depending on their number and configuration. A bifid mandibular canal is an anatomical variation reported more commonly than the trifid variant. Because of these variations, it is of the utmost importance to determine the exact location of the mandibular canal and to identify any branches arising from it prior to performing surgery in the mandible. This article reviews the prevalence, classification and morphometric measurements of these accessory mandibular canals, emphasizing their clinical significance.
A New Alkaloid from the Aerial Parts of Bupleurum chinense DC.
Authors: Xiao Zong‐Yu , Liu Yan , Sun Yan‐Ping , Liu Yuan , Yang Bing‐You , Kuang Hai‐Xue
Published: January 2020

A new isoalloxazine alkaloid, named bupleurine A (1), along with five known compounds (2–6), were isolated from the aerial parts of Bupleurum chinense DC. The structure elucidation of the new alkaloid (1) was employed by combining NMR and HR‐MS data with comparison of reference in the literature. Five known compounds (2–6) were isolated from Bupleurum genus for the first time. Additionally, their antiproliferative activities on HeLa cells were evaluated by MTT assay and IC50 of compounds 1 and 4–6 were below 10 μm after treatment for 24 h.
Peroxidase Encapsulated in Peroxidase Mimics via in situ Assembly with Enhanced Catalytic Performance
Authors: Wu Xiaoling , Xiong Jun , Liu Shuli , Chen Bin , Liang Shan , Lou Wenyong , Zong Minhua
Published: January 2020

Enzymatic catalysis is of great importance due to its high catalytic activity and high selectivity. However, intrinsic fragile property of enzyme limits its application in a wide range, where inactive inorganic materials have proven promising in enhancing the stability of the enzyme in industry. Here, Prussian blue nanoparticles (PB) as peroxidase mimics were adopted for encapsulation of peroxidase, Cytochrome c (Cyt c). Prussian blue/Cytochrome c (PB@Cyt c) composite developed via in‐situ assembly exhibited a 2.6‐fold higher apparent enzymatic activity than the sum activity of equivalent Cyt c and PB due to synergistic effect. Mechanism investigation showed that interaction between irons ions from PB and carbonyl group and nitrogen from enzyme led to a favorable catalytic conformation of Cyt c. Moreover, PB shielded the encapsulated Cyt c against harsh conditions (e. g. high temperature and organic solvents). This new efficient hybrid catalyst would open opportunities for wide applications in biosensors and biocatalysis.
Design, Synthesis and High HER Performances of 3D Ni/Mo Sulfide on Ni Foam
Authors: Liang Chong , Cao Wei , Zhou Linsen , Yang Pan , Zhao Xiaochong , Zhao Pengxiang , Qiu Ruizhi , Yang Lijun , Huang Qing‐song , Astruc Didier
Published: January 2020

Exploring noble‐metal‐free and earth‐abundant electrocatalysts for the hydrogen evolution reaction (HER) is an efficient way to mitigate energy and protect the environment. Herein, a noble‐metal‐free core‐shell catalyst, MoS2/Ni3S2/NF, was designed for HER and synthesized using a simple one‐step hydrothermal method. The MoS2−Ni3S2 hetero‐structured nanorods show a high HER performance with an overpotential of 93 mV at a current density of 10 mA/cm2 in alkaline conditions. The study combines density function theory (DFT) calculation with electrochemical experiments proved that the strong coupling synergy between MoS2 and Ni3S2 optimizes the electronic structure of the product and reduces the adsorption energy of water molecules, thus significantly enhancing the electrochemical HER activity. This work reveals the reaction mechanism of electrochemical hydrolysis and might shed some new lights on the design and fabrication of efficient and robust three‐dimensional hybrid electrode materials for a variety of electrochemical applications
Photophysical and Electrochemiluminescence of Coumarin‐Based Oxazaborines
Authors: Mikysek Tomáš , Nikolaou Pavlos , Kafexholli Mirjeta , Šimůnek Petr , Váňa Jiří , Marková Aneta , Vala Martin , Valenti Giovanni
Published: January 2020

We describe the synthesis, electrochemistry, photophysics, computational analysis and electrochemiluminescence (ECL) of a new series of oxazaborine molecules. Our strategy is based on the modification of the coumarin‐oxazaborine moiety to be directly joined through a carbon‐carbon bond, forming donor‐acceptor (D‐A) chromophores. These new structures substantially change the electron distribution as well as photophysical and electrochemical behaviors with a strong effect on the final quantum yield. For all compounds, we observed a very high PL quantum yield (70–75 %) and relatively accessible first oxidation and first reduction. All of these characteristics allow us to study the ECL of these molecules, obtaining a very high ECL efficiency that is four times higher than the standard dyes, opening the application of oxazaborine as bright ECL luminophores.
Comparison of supervised learning statistical methods for classifying commercial beers and identifying patterns
Authors: Koren Dániel , Lőrincz Laura , Kovács Sándor , Kun‐Farkas Gabriella , Vecseriné Hegyes Beáta , Sipos László
Published: January 2020

In this study, 13 properties (alcohol‐, real extract‐, flavonoid‐, anthocyanin, glucose, fructose, maltose, sucrose content, EBC [European Brewery Convention] and L*a*b* color, bitterness) of 21 beers (alcohol‐free pale lagers, alcohol‐free beer‐based mixed drinks, beer‐based mixed drinks, international lagers, wheat beers, stouts, fruit beers) were determined. In the first step, multiple factor analysis (MFA) was performed for the whole data and five clusters (target classes) were determined; then, a bootstrapping was applied to establish a balanced data so as every cluster should contain 100 samples and the total sample size is 500. In the second step, 12 supervised learning algorithms (random trees [RND], Quinlan's C4.5 decision tree algorithm [C4.5], Iterative Dichotomiser 3 algorithm [ID3], cost‐sensitive decision tree algorithm [CSMC4], cost‐sensitive classification tree [CSCRT], k‐nearest neighbors algorithm [KNN], radial basis function [RBF], multilayer perceptron neural network [MLP], prototype nearest neighbor [PNN], linear discriminant analysis [LDA], naïve Bayes with continuous variables [NBC], partial least squares discriminant analysis [PLS‐DA]) were applied to classify each brand into the target classes. Furthermore, several error rates were calculated: re‐substitution error rate (RER), cross‐validated error rate (CV), bootsrap error (BOOT), leave‐one‐out (LOO), and train‐test error rate (TRAIN). The MFA could discriminate five groups, which can be characterized by some analytical parameters, and the other multivariate methods performed similarly. The methods can be discriminated best based on the BOOT, CV, and LOO. The best estimation methods are the C4.5, CSMC4, and CSCRT; these performed best along the flavonoid content and EBC color. It identified that the methods most sensitive to the properties are the NBC. The classification ability fluctuated greatly in the case of three properties (glucose, maltose, sucrose). A remarkable fluctuation has been experienced in the case of L*a*b* color parameters, flavonoid content, EBC color, and bitterness by NBC method.
Elucidation of the chromatographic enantiomer elution order for praziquantel: An experimental and theoretical assessment
Authors: Silva Camilla Fonseca , do Nascimento Tienne Aparecida , Guimarães Luciana , Borges Keyller Bastos , Nascimento Clebio Soares
Published: January 2020

In this work, we have studied both experimentally and theoretically the praziquantel (PZQ) chiral discrimination. According to the main results, the enantioseparation of PZQ was efficiently optimized by HPLC on the reverse phase from the Chiralpak IB column, which has cellulose tris (3,5‐dimethylphenylcarbamate) (CDMPC) as a chiral selector. The thermodynamic and structural parameters obtained via density functional theory (DFT) calculations pointed out the chiral discrimination as well as the enantiomeric elution order of PZQ, thus elucidating the experimental data and validating our proposed method. Finally, the hydrogen bonds and π‐π stacking interactions played a key role in the discrimination between the PZQ diastereomeric complexes formed.
Towards efficient design optimization of a miniaturized thermoelectric generator for electrically active implants via model order reduction and submodeling technique
Authors: Yuan Chengdong , Kreß Stefanie , Sadashivaiah Gunasheela , Rudnyi Evgenii B. , Hohlfeld Dennis , Bechtold Tamara
Published: January 2020

Thermoelectric generators (TEG) convert the thermal energy into electrical energy and are under investigation as a power supply for medical implants. To improve the performance of TEG, the design optimization process through finite element model simulation is preferred by biomedical engineers. This paper aims to provide an efficient method of speeding up the design optimization process of TEG. A three‐dimensional realistic human torso model incorporating the TEG is investigated, where the internal heat transfer in human tissue is characterized by Pennes bioheat equation. In addition, convection, radiation, and evaporation effects at the skin surface are applied to identify the heat transfer effects between the human body and the environment. To speed up finite element simulation of the large‐scale human torso model, projection‐based model order reduction (MOR) is applied for generation of a compact but highly accurate model. Parametric MOR (pMOR) further enables generating a parameter‐independent compact model. For an efficient design optimization of TEG, this compact human torso model is applied within a thermal submodeling approach. Its temperature distribution results are back‐projected and used as boundary conditions for the TEG submodel. The achieved speed‐up in simulation time, demonstrated in this work, clearly indicates that the design optimization process of TEG is more efficient with the combination of MOR and submodeling techniques.
A Self‐Adjuvanting Vaccine Platform: Optimization of Site‐Specific Sortase A Mediated Conjugation of Toll‐Like Receptor 2 Ligands onto the Carboxyl or Amino terminus of Recombinant Protein Antigens
Authors: Xu Zhenghui , Moyle Peter Michael
Published: January 2020

Self‐adjuvanting vaccines, consisting of recombinant protein antigens and covalently attached Toll‐like receptor (TLR) agonists, have the ability to simultaneously and efficiently deliver antigen and TLR adjuvant to antigen presenting cells (APCs). Here, an enzyme‐mediated ligation approach was used to overcome difficulties in producing homogeneous, molecularly defined self‐adjuvanting vaccine products under native conditions. This process was optimized to allow the incorporation of the lipopeptide TLR2 agonist fibroblast‐stimulating lipopeptide (FSL)‐1 onto the N‐ or C‐termini of recombinant protein antigens, employing the enzyme Staphylococcus aureus sortase A (SrtAsa) penta mutant. In addition, because SrtAsa‐mediated ligations are reversible, a tryptophan zipper derived sequence was introduced into both reactants, which was demonstrated to improve ligation efficiency through the formation of a β‐hairpin structure that hinders the reverse reaction. Finally, it was demonstrated that N‐ or C‐terminal conjugation, and the incorporation of the β‐hairpin structure, did not affect the TLR2‐agonist activities of protein antigen TLR agonist conjugates. Overall, this SrtAsa‐mediated ligation platform enabled production of antigen TLR2 agonist conjugates with enhanced ligation efficiency, with the conjugates demonstrating potent TLR2 signaling activation (EC50<1nM).
Prediction of progression from pre‐diabetes to diabetes: Development and validation of a machine learning model
Authors: Cahn Avivit , Shoshan Avi , Sagiv Tal , Yesharim Rachel , Goshen Ran , Shalev Varda , Raz Itamar
Published: January 2020

Aims

Identification, a priori, of those at high risk of progression from pre‐diabetes to diabetes may enable targeted delivery of interventional programmes while avoiding the burden of prevention and treatment in those at low risk. We studied whether the use of a machine‐learning model can improve the prediction of incident diabetes utilizing patient data from electronic medical records.

Methods

A machine‐learning model predicting the progression from pre‐diabetes to diabetes was developed using a gradient boosted trees model. The model was trained on data from The Health Improvement Network (THIN) database cohort, internally validated on THIN data not used for training, and externally validated on the Canadian AppleTree and the Israeli Maccabi Health Services (MHS) data sets. The model's predictive ability was compared with that of a logistic‐regression model within each data set.

Results

A cohort of 852 454 individuals with pre‐diabetes (glucose ≥ 100 mg/dL and/or HbA1c ≥ 5.7) was used for model training including 4.9 million time points using 900 features. The full model was eventually implemented using 69 variables, generated from 11 basic signals. The machine‐learning model demonstrated superiority over the logistic‐regression model, which was maintained at all sensitivity levels – comparing AUC [95% CI] between the models; in the THIN data set (0.865 [0.860,0.869] vs 0.778 [0.773,0.784] P < .05), the AppleTree data set (0.907 [0.896, 0.919] vs 0.880 [0.867, 0.894] P < .05) and the MHS data set (0.925 [0.923, 0.927] vs 0.876 [0.872, 0.879] P < .05).

Conclusions

Machine‐learning models preserve their performance across populations in diabetes prediction, and can be integrated into large clinical systems, leading to judicious selection of persons for interventional programmes.
Transcriptomic regulation of seasonal coat color change in hares
Authors: Ferreira Mafalda S. , Alves Paulo C. , Callahan Colin M. , Giska Iwona , Farelo Liliana , Jenny Hannes , Mills L. Scott , Hackländer Klaus , Good Jeffrey M. , Melo‐Ferreira José
Published: January 2020

Color molts from summer brown to winter white coats have evolved in several species to maintain camouflage year‐round in environments with seasonal snow. Despite the eco‐evolutionary relevance of this key phenological adaptation, its molecular regulation has only recently begun to be addressed. Here, we analyze skin transcription changes during the autumn molt of the mountain hare (Lepus timidus) and integrate the results with an established model of gene regulation across the spring molt of the closely related snowshoe hare (L. americanus). We quantified differences in gene expression among three stages of molt progression—“brown” (early molt), “intermediate,” and “white” (late molt). We found 632 differentially expressed genes, with a major pulse of expression early in the molt, followed by a milder one in late molt. The functional makeup of differentially expressed genes anchored the sampled molt stages to the developmental timeline of the hair growth cycle, associating anagen to early molt and the transition to catagen to late molt. The progression of color change was characterized by differential expression of genes involved in pigmentation, circadian, and behavioral regulation. We found significant overlap between differentially expressed genes across the seasonal molts of mountain and snowshoe hares, particularly at molt onset, suggesting conservatism of gene regulation across species and seasons. However, some discrepancies suggest seasonal differences in melanocyte differentiation and the integration of nutritional cues. Our established regulatory model of seasonal coat color molt provides an important mechanistic context to study the functional architecture and evolution of this crucial seasonal adaptation.
Efficacy and safety of sodium zirconium cyclosilicate for hyperkalaemia: the randomized, placebo‐controlled HARMONIZE‐Global study
Authors: Zannad Faiez , Hsu Bang‐Gee , Maeda Yoshitaka , Shin Sug Kyun , Vishneva Elena M. , Rensfeldt Martin , Eklund Stefan , Zhao June
Published: January 2020

Aims

Sodium zirconium cyclosilicate (SZC, formerly ZS‐9) is a selective K+ binder to treat adults with hyperkalaemia. HARMONIZE‐Global examined the efficacy and safety of SZC among outpatients with hyperkalaemia from diverse geographic and ethnic origins.

Methods and results

This phase 3, randomized, double‐blind, placebo‐controlled study recruited outpatients with serum K+ ≥5.1 mmol/L (measured by point‐of‐care i‐STAT device) at 45 sites in Japan, Russia, South Korea, and Taiwan. Following open‐label treatment with thrice‐daily SZC 10 g during a 48 h correction phase (CP), patients achieving normokalaemia (K+ 3.5–5.0 mmol/L) were randomized 2:2:1 to once‐daily SZC 5 g, SZC 10 g, or placebo during a 28 day maintenance phase (MP). The primary endpoint was mean central‐laboratory K+ level during days 8–29 of the MP. Of 267 patients in the CP, 248 (92.9%) entered the MP. During the CP, mean central‐laboratory K+ was reduced by 1.28 mmol/L at 48 h vs. baseline (P < 0.001). During the MP (days 8–29), SZC 5 and 10 g once‐daily significantly lowered mean central‐laboratory K+ by 9.6% and 17.7%, respectively, vs. placebo (P < 0.001 for both). More patients had normokalaemia (central‐laboratory K+ 3.5–5.0 mmol/L at day 29) with SZC 5 (58.6%) and 10 g (77.3%) vs. placebo (24.0%), with the greatest number of normokalaemic days in the 10‐g group. The most common adverse events with SZC were mild or moderate constipation and oedema.

Conclusions

Normokalaemia achieved during the CP was maintained over 28 days with SZC treatment among outpatients with hyperkalaemia.
Synthesis and Characterization of Cationic Platinum(II) Complexes with Two Chelating Ligands
Authors: Bárta Ondřej , Pinter Piermaria , Císařová Ivana , Strassner Thomas , Štěpnička Petr
Published: January 2020

A series of cationic Pt(II) complexes with chelating bis‐carbene and P,P‐ or P,S‐ligands, viz. [(C^C)Pt(X^Y)][BF4]2 (2a–e), where C^C = methylenebis(3‐methyl‐1H‐imidazol‐1‐yl‐2‐ylidene, and X^Y = Ph2PCH2CH2PPh2 (dppe) (a), Ph2P(CH2)3PPh2 (dppp) (b), 1,2‐(Ph2P)2C6H4 (dppbz) (c), [Fe(η5‐C5H4PPh2)2] (dppf) (d), and Ph2PCH2CH2SPh (e), were synthesized and structurally characterized by NMR and MS spectroscopy and by single‐crystal X‐ray diffraction analysis. Furthermore, photophysical measurements showed that these compounds were non‐emissive at room temperature. However, when cooled to 77 K, compounds 2a, 2b and 2c showed weak luminescence in the near UV region with emission maxima in the 380–395 nm range.
NICS – Past and Present
Authors: Stanger Amnon
Published: January 2020

The Nucleus Independent Chemical Shift (NICS) method was invented in 1996 by the late Paul v. R. Schleyer as a computational tool for the assessment of aromaticity. In the intervening years, NICS has developed considerably. This Minireview describes the NICS‐based methods that are currently available and concludes with recommendations for choosing the appropriate NICS‐based methods to study a given problem.
Misfire detection of homogeneous charge compression ignition engines using matter‐element extension theory and thermodynamic multi zone model
Authors: Asghari Mohsen , Saray Rahim Khoshbakhti , Neshat Elaheh
Published: January 2020

Nowadays, researchers tend to simulate and model the studied phenomena to reduce the calculation time and cost. Matter‐element extension model is a useful method that can be used to evaluate a wide range of data that belong to different subjects. In this study, this model is used to diagnose different engine's performance modes including misfire, normal, knock, and middle modes in which both of the mentioned modes are occurred simultaneously. To achieve this purpose, a set of performance and emission parameters acquired for a multi zonal model are chosen as input data to the model. Statistical analysis is done on a set of experimental data. First, ANOVA (analysis of variance) is used to determine parameters significant level. Then the proportional weights are given for the chosen parameters with respect to their importance. To do this, linear regression analysis is used for determination of weights. Two kinds of single objective and two objectives matter‐element extension models are employed to diagnose the engine's operation mode. The results show that both the single objective and two objectives models show a good conformity with the corresponding experimental results without acquiring empirical data. Single objective model can predict misfire, normal combustion, and knocking combustion. Meanwhile the two objectives model can predict the middle modes containing normal‐misfire, misfire‐knock, and knock‐normal accurately.
Exergoeconomic analysis and optimization of reverse osmosis desalination integrated with geothermal energy
Authors: Hoseinzadeh Siamak , Yargholi Roya , Kariman Hamed , Heyns P. Stephan
Published: January 2020

In this research, the integrated carbon dioxide power cycle with the geothermal energy source to supply the required reverse osmosis desalination power for freshwater production is defined. The cycling power is consumed by the desalination system and sodium hypochlorite generator. Exergoeconomic analysis, and optimization are studied. Exergoeconomic analysis is shown that the desalination system, sodium hypochlorite generator, carbon dioxide turbine, and natural gas turbine have the highest rate for the sum of capital gain and exergy destruction cost. For the first case of optimization, the total cost rate is considered as the objective function. The optimal inlet discharge rate of sodium hypochlorite generator was 62% of the brine water outlet discharge rate of the desalination system. Plus, the total cost rate is reduced by 10% compared to the general case when 100% of brine water discharge rate of the desalination system enters into the sodium hypochlorite generator. The second case is multiobjective optimization to reduce costs and increase productivity.
Clast transport history influences Schmidt hammer rebound values
Authors: Olsen Telemak , Borella Josh , Stahl Timothy
Published: January 2020

The Schmidt hammer (SH) is widely used in geomorphology for relative‐ and calibrated‐exposure age dating surfaces and deposits within landforms. This study employs a laboratory‐based methodology to assess the effects of surface roughness, clast roundness, and clast volume on SH rebound values (R‐values) by analyzing samples from three modern depositional environments (i.e. river, alluvial fan, talus). Each environment contains clasts of Torlesse supergroup greywacke sandstones with distinct roundness and micro‐scale roughness characteristics. Roundness, surface roughness, and clast volume were all found to influence R‐values significantly. The R‐values from different deposit types are statistically significant and could potentially create an apparent age divergence of several thousand years for samples with the same exposure‐age. © 2020 John Wiley & Sons, Ltd.
Bedrock erosion due to hoeing as tillage technique in a hilly agricultural landscape, southwest China
Authors: Xu Haichao , Zhang Jianhui , Wei Yuhang , Dai Jiadong , Wang Yong
Published: January 2020

Tillage on hillslopes may not only induce severe soil erosion, but may also cause bedrock erosion under certain conditions. Yet, little is known about bedrock erosion by tillage in a hilly agricultural landscape, southwest China. The aim of this study is to quantify the translocation of rock fragments derived from bedrock fragmentation by hoeing under different conditions, including slope gradient, hoeing depth and soil‐covered thickness using a gravel tracing method. The reliability of the gravel tracing method was confirmed by the bedrock dyeing tracing method. Hoeing depth is a significant factor affecting the translocation rate of rock fragments (Qr). Meanwhile, under the condition of overlying soil layers (0.06−0.10 m thick), the values of Qr were significantly smaller with a reduction of 20.7−25.6%, compared with rock fragmentation by hoeing for bare bedrock. However, slope gradient was found to have insignificant effects on Qr. Fractured bedrock moved as individual small fragments, which was mainly controlled by the hitting force of the hoe, while soil moved in the shape of lumps, which was dominated by both drag force of the hoe and gravity. This study suggests that hoeing into soil‐covered bedrock can diminish bedrock erosion while providing soil matrix for shallow soil layers. Our work presents a quantitative assessment of bedrock erosion by hoeing and an underlying insight into characteristics of bedrock erosion by tillage operations in hilly agricultural regions with mudstone and shale, southwest China. © 2020 John Wiley & Sons, Ltd.
A novel silicon graphite composite material with core‐shell structure as an anode for lithium‐ion batteries
Authors: Yin Ao , Yang Lezhi , Zhuang Zilong , Feng Qingge , Liu Zhikuan , Chen Tao , Tu Feiyue , Peng Qinjiao , Luo Lei , Tang Gang , Chen Wenqiang , Qin Shibiao , Wu Jianghua
Published: January 2020

In this work, a novel core‐shell structure consisting of a porous graphite core, a nanosilicon filler layer, and a pitch coating carbon shell has been developed for lithium‐ion battery anode material. This structure was prepared by liquid‐phase milling and carbonization processes. Compared with other silicon (Si)‐based anode materials, this structure has a unique three‐dimensional conductive network consisting of conductive materials of conductive carbon, graphene, porous graphite, and carbon shell. The conductive network could effectively enhance the conductivity of the core‐shell structure. In addition, this structure was designed with moderate porous rate that provided nanosilicon appropriate expansion space. The coin cell test showed that this new material has a reversible capacity of 400 mA h g−1, retention of above 95% after 40 cycles, an initial columbic efficiency of 83.04%, and an average coulombic efficiency of above 99%. This novel material could have a great potential for future commercial application. The structure designed could be a possible solution for Si anode materials with low manufacturing cost and high performance.
High‐intensity ultrasound applied on cured pork: Sensory and physicochemical characteristics
Authors: Contreras‐Lopez German , Carnero‐Hernandez Andrea , Huerta‐Jimenez Mariana , Alarcon‐Rojo Alma Delia , Garcia‐Galicia Ivan , Carrillo‐López L. M.
Published: January 2020

This research aimed to evaluate the physicochemical characteristics and their relationship with sensory properties of cured porcine m. longissimus lumborum assisted by high‐intensity ultrasound (HIU, 37 kHz, 22 Wcm−2). An experiment was designed with three factors at two levels each: type of curing (immersion or ultrasound‐assisted ‐UA‐), immersion time (30 or 90 min), and steak thickness (1.27 or 2.54 cm). After treatment and 7 days of storage at 4°C, the percentage of salt, pH, CIE L* a* b* color, water holding capacity (WHC), and shear force were determined in the samples. A quantitative descriptive analysis was performed using eight trained panelists. The HIU significantly increased the percentage of NaCl (p < .0005) and decreased the color saturation of the meat (p < .05), but did not affect the luminosity, redness (a*), yellowness (b*), pH, WHC, or shear force (all p > .05). The thickness of the steak had significant effects on almost all of the evaluated variables. Samples with 1.27 cm thickness had lower shear force, higher WHC and salt percentage (p < .0001). In agreement with this, the sensory profiles showed that the 1.27 cm samples treated with HIU for 30 min were perceived as less tough (more tender) and juicier.