bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of genes encoding small heat shock proteins from Bemisia tabaci and expression under thermal stress
Authors: Bai Jing , Liu Xiao-Na , Lu Ming-Xing , Du Yu-Zhou
Published: June 2019

Small heat shock proteins (sHSPs) are probably the most diverse in structure and function among the various super-families of stress proteins, and they play essential roles in various biological processes. The sweet potato whitefly, Bemisia tabaci (Gennadius), feeds in the phloem, transmits several plant viruses, and is an important pest on cotton, vegetables and ornamentals. In this research, we isolated and characterized three α-crystallin/sHSP family genes (Bthsp19.5, Bthsp19.2, and Bthsp21.3) from Bemisia tabaci. The three cDNAs encoded proteins of 171, 169, and 189 amino acids with calculated molecular weights of 19.5, 19.2, and 21.3 kDa and isoelectric points of 6.1, 6.2, and 6.0, respectively. The deduced amino acid sequences of the three genes showed strong similarity to sHSPs identified in Hemiptera and Thysanoptera insects species. All three sHSPs genes from Bemisia tabaci lacked introns. Quantitative real-time PCR analyses revealed that the three BtsHSPs genes were significantly up-regulated in Bemisia tabaci adults and pupae during high temperature stress (39, 41, 43, and 45 °C) but not in response to cold temperature stress (−6, −8, −10, and −12 °C). The expression levels of Bthsp19.2 and Bthsp21.3 in pupae was higher than adults in response to heat stress, while the expression level of Bthsp19.5 in adults was higher than pupae. In conclusion, this research results show that the sHSP genes of Bemisia tabaci had shown differential expression changes under thermal stress.
Bibliometric analysis of research on the trends in autophagy
Authors: Hong Ting , Feng Xinzhe , Tong Wenwen , Xu Weidong
Published: June 2019

Background

Autophagy is an important mechanism to maintain homeostasis in cells. It has been linked with ageing and many currently incurable diseases, including heart disease, cancer, myopathies, neurodegeneration, and diabetes. Autophagy research is very important for identifying better treatments. This study aimed to explore the hotspots of autophagy research published from different countries, organizations, and authors.

Methods

Between 1962 and 2018, articles published about autophagy were identified in the Web of Science database. The total and annual number of articles, citations, impact factor, Hirsch (H)-index, number of article citations, productive authors, and involved journals were collected for quantitative and qualitative comparisons.

Results

From 1962 to 2018, 18,811 autophagy-related articles written in English were published. Most were from China (6,731). The United States dominated in citation frequency (391,030) and h-index (264). Among related journals, Autophagy published the most articles (1,388), followed by Plos One (585) and Oncotarget (392). Daniel Klionsky was the most productive author, with 171 publications. The article “LC3, a mammalian homologue of yeast Apg8p, is localized in autophagosome membranes after processing” was cited most frequently. The top-ranked keyword was “degradation” of macroautophagy.

Conclusions

Publication of articles about autophagy has increased notably from 1962 to 2018, and has increased annually. The general quality of publications from China is still in need of improvement. Autophagy research has shifted gradually from basic studies to clinical studies in recent years.
Cryo‐EM structure of the MinCD copolymeric filament from Pseudomonas aeruginosa at 3.1 Å resolution
Authors: Szewczak‐Harris Andrzej , Wagstaff James , Löwe Jan
Published: June 2019

Positioning of the division site in many bacterial species relies on the MinCDE system, which prevents the cytokinetic Z‐ring from assembling anywhere but the mid‐cell, through an oscillatory diffusion‐reaction mechanism. MinD dimers bind to membranes and, via their partner MinC, inhibit the polymerization of cell division protein FtsZ into the Z‐ring. MinC and MinD form polymeric assemblies in solution and on cell membranes. Here, we report the high‐resolution cryo‐EM structure of the copolymeric filaments of Pseudomonas aeruginosa MinCD. The filaments consist of three protofilaments made of alternating MinC and MinD dimers. The MinCD protofilaments are almost completely straight and assemble as single protofilaments on lipid membranes, which we also visualized by cryo‐EM.
Control effect of large tuned mass damper used for seismic retrofitting of existing high‐rise building
Authors: Nakai Takeshi , Kurino Haruhiko , Yaguchi Tomoki , Kano Naoki
Published: June 2019

We developed a large tuned mass damper (TMD) for counteracting the effects of long‐period earthquakes in existing high‐rise buildings. The TMD consists of a suspended weight and oil dampers with stroke control functions. The damper increases its damping coefficient when the TMD weight velocity reaches a predetermined value, preventing overstroke during large earthquakes. The system controls the TMD stroke with minimum impact on its response control performance. This paper describes the development and application of the TMD and verification of the response control performance using observation records. First, we examine the requirements for this type of TMD using a simple analytical model and determine the influence of the stroke control on the response control performance. Next, an example application is outlined. The components required for realization of the TMD are addressed, and a project for the seismic upgrade of an existing high‐rise building is described. To evaluate the response control performance, we developed accurate simulation models for the building and TMD, and we analytically confirmed the response control performance. Finally, this paper presents observation records obtained during an earthquake and strong wind. The control effect of the TMD was verified through comparison of the observation records and analytical results.
Ikura Nursery School
Authors: Matsushima Jumpei
Published: June 2019

A nursery school with a skip floor design is situated at the top of a fluvial terrace. This building comprises 4‐tiered floors that reflect the terraced landform characteristic of Iida City. Each grade has a triplet‐type classroom with an environment and role that is highly individuated by the arrangement of various textures of materials. In addition, a semi‐outdoor “grand staircase” is set in the east side of the site, connecting the ground level to the top floor directly and providing 3‐dimensional circulation from the inside to the outdoors. In addition to serving as tiered stands for parents to use at events such as athletic festivals, it plays a symbolic role in the locality. By designing the space in a way that fosters children's development of crisis management skills, this nursery aims to allow children to be active within and outside the building as their minds and bodies grow.
Overranging and overbeaming measurement in area detector computed tomography: A method for simultaneous measurement in volume helical acquisition
Authors: Urikura Atsushi , Hara Takanori , Yoshida Tsukasa , Nishimaru Eiji , Hoshino Takashi , Nakaya Yoshihiro , Endo Masahiro
Published: June 2019

Purpose

We propose a novel method to assess overbeaming and overranging, as well as the effect of reducing longitudinal exposure range, by using a dynamic z‐collimator in area detector computed tomography.

Methods and materials

A 500‐mm diameter cylindrical imaging plate was exposed by helical scanning in a dark room. The beam collimation of the helical acquisitions was set at 32 and 80 mm. Overbeaming and overranging with the dynamic z‐collimator were measured.

Results

The actual beam widths were approximately 39 and 88 mm at 32 and 80 mm collimation, respectively, and were relatively reduced owing to increased beam collimation. Overranging was 27.0 and 48.2 mm with a pitch of 0.83 and 1.49 at 32 mm collimation and 72.5 and 83.1 mm with a pitch of 0.87 and 0.99 at 80 mm collimation. The dynamic z‐collimator relatively reduced the overranging by 17.3% and 17.1% for the 32 and 80 mm collimation, respectively.

Conclusion

We devised a method to simultaneously measure overbeaming and overranging with only one helical acquisition. Although the dynamic z‐collimator reduced the overranging by approximately 17%, wider collimation widths and higher pitch settings would increase the exposure dose outside the scan range.
Sustainable and Self‐Enhanced Electrochemiluminescent Ternary Suprastructures Derived from CsPbBr3 Perovskite Quantum Dots
Authors: Li Lingling , Zhang Ziyi , Chen Ying , Xu Qin , Zhang Jian‐Rong , Chen Zixuan , Chen Yun , Zhu Jun‐Jie
Published: June 2019

Lead halide perovskite quantum dots (QDs) are promising electrochemiluminescence (ECL) nanoemitters due to their fascinating photophysical properties. However, due to their poor structural stability against the external environment, the trade‐off between their colloidal stability and carrier injection/transport efficiency is a major challenge in the advancement of perovskite‐based ECL technology. In this work, intense and stable ECL from CsPbBr3 (CPB) QDs is achieved by simultaneously encapsulating CPB QDs and coreactant (CoR) into in situ generated SiO2 matrix via hydrolysis of tetramethyl orthosilicate. The well‐designed architecture of the as‐obtained CPB‐CoR@SiO2 nanocomposites (NCs) guarantees not only greatly improved stability thanks to the peripheral SiO2 protecting matrix, but also efficient self‐enhanced ECL between CPB and the intra‐coreactants. Consequently, by elaborately selecting the CoR molecules with different tertiary/secondary amines and functional groups, multifold higher (up to 10.2 times) ECL efficiencies are obtained for the CPB‐CoR@SiO2 NCs alone in reference to the standard Ru(bpy)32+/tri‐n‐propylamine system. This work provides an efficient design strategy for obtaining stable and highly efficient ECL from perovskite QDs, and offers a new perspective for the development and application of perovskite‐based ECL system.
Kinetics Enhanced Nitrogen‐Doped Hierarchical Porous Hollow Carbon Spheres Boosting Advanced Potassium‐Ion Hybrid Capacitors
Authors: Qiu Daping , Guan Jingyu , Li Min , Kang Cuihua , Wei Jinying , Li Yan , Xie Zhenyu , Wang Feng , Yang Ru
Published: June 2019

Potassium‐ion hybrid capacitors (PIHCs) shrewdly combine a battery‐type anode and a capacitor‐type cathode, exhibiting an energy density close to that of potassium ion batteries and a comparable power density of supercapacitors. However, the rosy scenario is compromised by the sluggish kinetics in the PIHCs device. Herein, the kinetics enhanced nitrogen‐doped hierarchical porous hollow carbon spheres (NHCS) are synthesized and successfully applied to PIHCs. As for the K half‐cell, NHCS anchored with sodium alginate delivers excellent electrochemical performance. Further evaluation shows that the binder can significantly affect the potassium storage performance of NHCS by adjusting the coatability and ionic conductivity of the NHCS anode. Moreover, kinetic analysis and density functional theory calculations reveal the origin of the superior electrochemical properties of NHCS. As expected, an advanced PIHC device is assembled with a NHCS anode and an activated NHCS cathode, demonstrating an exceptionally high energy/power density (114.2 Wh kg−1 and 8203 W kg−1), along with a long‐life capability. The successful construction of high‐performance PIHCs in this work opens a new avenue for the development and application of PIHCs in the future.
Modeling of Negative Capacitance in Ferroelectric Thin Films
Authors: Park Hyeon Woo , Roh Jangho , Lee Yong Bin , Hwang Cheol Seong
Published: June 2019

The negative capacitance (NC) effect in ferroelectric thin films has attracted a great deal of attention from the material and semiconductor device communities because it could be a possible solution to the impending problems related to field‐effect transistor power consumption and dynamic random‐access memory charge loss. A short discussion on the fundamental premise of the NC effect is presented. A phase‐field model based on the time‐dependent Ginzburg–Landau (TDGL) formalism in conjunction with the Chensky–Tarasenko (C–T) formalism for multidomain configuration is then developed to reveal the subtle correlation between the domain wall motion and NC effect for different thicknesses of ferroelectric and dielectric films. When a ferroelectric film becomes thin enough, a stripe domain structure can be achieved through competition between the electrostatic energy and domain wall energy. This stripe domain structure is quite resilient to transition to a homogeneous polarization state, making it very useful for (quasi‐)static NC operation. Finally, the physical implications of the numerical results are explored with analytical modeling. It is identified that the domain wall motion in the stripe domain structure remains dominated by the external field, even when the entire film is in the (quasi‐)static NC state.
Polymer‐Assisted Deposition of Al‐Doped HfO2 Thin Film with Excellent Dielectric Properties
Authors: Park Gyeongbae , Yang Heeseung , Lee Ju Hyun , Lee Gilwoon , Kwak Junghyeok , Jeong Unyong
Published: June 2019

Demands for high‐k dielectric materials increase as transistors scale down. One of the promising high‐k dielectric materials is HfO2 owing to its large band gap, high dielectric constant, and excellent physical/chemical stability. Although several cost‐effective solution‐based deposition methods have been developed, their dielectric performances are inferior to those obtained by vacuum processes (e.g., atomic layer deposition, sputtering). This study demonstrates a solution‐based polymer‐assisted deposition (PAD) of high‐k Al‐doped HfO2 thin films exhibiting remarkable dielectric performances comparable to the conventional deposition methods. The PAD ensures the control of film thickness (≥3 nm) and the homogenous Al doping in the entire thin film. The key to the success is HCl‐mediated coordination of metal precursor and polymer. Thorough analysis on the structure and chemical composition of the dielectric layer is carried out. It is found that the phase transition from monoclinic phase to a mixture of tetragonal and amorphous phases results in excellent dielectric properties. The 7.8 nm thick thin film doped with 4.1 at% of Al exhibits a high dielectric constant of 30.2 with a high areal capacitance (674 nF cm−2 at 1.0 kHz), a low leakage current (3.3 × 10−9 A cm−2 at 2.0 MV cm−1), and a high breakdown voltage (7.7 V).
Novel Strategy for Constructing High Efficiency OLED Emitters with Excited State Quinone‐Conformation Induced Planarization Process
Authors: Wu Haozhong , Pan Yuyu , Zeng Jiajie , Du Lili , Luo Wenwen , Zhang Han , Xue Kaiqi , Chen Ping , Phillips David Lee , Wang Zhiming , Qin Anjun , Tang Ben Zhong
Published: June 2019

In contrast to the common intramolecular charge transfer (ICT) emission, planarized intramolecular charge transfer (PLICT) based materials usually possess higher proportion radiative decay for their flat and rigid conformation in excited states. Herein, a strategy for designing PLICT‐based emitters by the excited state quinone‐conformation induced planarization is proposed. By virtue of RIR mechanism on TPP (tetraphenylpyrazinyl) unit, the newcomers named as TPP‐PPI (1‐phenyl‐2‐(4′‐(3,5,6‐triphenylpyrazin‐2‐yl)‐[1,1′‐biphenyl]‐4‐yl)‐1H‐phenanthro[9,10‐d] imidazole) and TPP‐PI (1‐phenyl‐2‐(4‐(3,5,6‐triphenylpyrazin‐2‐yl)phenyl)‐1H‐phenanthro[9,10‐d]imidazole) exhibit aggregation‐induced emission (AIE) characteristics. TPP‐PPI and TPP‐PI have obvious PLICT properties via series of spectral measurements. Employing theoretical calculation in ground and excited states in different solvents, their PLICT process is confirmed further, and TPP's contribution on PLICT formation becomes clear. In non‐doped organic light‐emitting diodes, these two emitters with AIE and PLICT characteristic exhibit good performance with external quantum efficiency (4.85% and 4.36%) as blue emitters.
Terahertz Spectroscopy of Nanomaterials: a Close Look at Charge‐Carrier Transport
Authors: Kužel Petr , Němec Hynek
Published: June 2019

Terahertz spectroscopy has been used for almost two decades for investigations of nanomaterials, including nanocrystals, nanoparticles, nanowires, nanotubes or 2D crystals. Its great importance stems from the fact that it is a noncontact method and, owing to its high frequency and broadband character, it is capable of characterizing charge transport properties within individual nano‐objects but also among them. In addition, probing of photoinitiated ultrafast charge dynamics is possible thanks to the sub‐picosecond time resolution. Despite this unprecedented potential, the interpretation of the measured terahertz conductivity spectra in many materials is still intensively debated. Herein is presented a review of the experiments performed on nanostructures of conventional semiconductors and on carbon nanomaterials (graphene and carbon nanotubes) during the past decade. The state of the art of the theoretical formalism is provided and discussed, including the intrinsic response, as well as the role of inherent heterogeneity and of the experimental conditions.
Hyperbranched Fractal Nanocarbons for Bright Photoluminescence in Solid State
Authors: Wang Ya‐Ling , Liu Bin , Yang Jia‐Liang , Cao Xiao‐Han , Yang Yong‐Zhen , Yang Qing , Greiner Andreas , Xu Jun‐Ting , Zhang Xing‐Hong
Published: June 2019

Nanocarbons with diverse structures have great potential applications in biomedicine, energy conversion, and catalysis owing to their unique photoelectric properties. This work describes bottom‐up synthesis of hyperbranched fractal nanocarbons (HFNs), using trimethylolpropane tri(cyclic carbonate) ether and ethylenediamine as the precursors. HFNs are formed by self‐assembly of in situ generated carbonized polymer dots (CPDs), driven by their low surface ζ‐potentials. Of significance, both CPDs and HFNs possess graphitized carbon core and functionalized shell with core edge layer, thus emit bright solid‐state luminescence with an absolute quantum yield of 11.7% at room temperature and strong phosphorescence at 77 K. The carbonyl cluster of these nanocarbons is mainly responsible for the strong photoluminescence emission. The application of HFNs is demonstrated for energy conversion, using them as single phosphor for fabricating multicolor light‐emitting diodes. This work outlines a fundamental principle to prepare HFNs with bright photoluminescence in solid state.
Visible‐Light‐Promoted Transition‐Metal‐Free Approach toward Phosphoryl‐Substituted Dihydroisoquinolones via Cascade Phosphorylation/Cyclization of N‐Allylbenzamides
Authors: Liu Xiao‐Ceng , Sun Kai , Chen Xiao‐Lan , Wang Wen‐Fei , Liu Yan , Li Qian‐Li , Peng Yu‐Yu , Qu Ling‐Bo , Yu Bing
Published: June 2019

A transition‐metal‐free visible‐light‐promoted radical phosphorylation/cyclization of N‐allylbenzamides with phosphine oxides for the synthesis of phosphoryl‐substituted dihydroisoquinolones was developed under room temperature. This protocol features mild reaction conditions, simple operation, broad substrate scope as well as scale‐up ability.

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Direct Assembly of Silica Nanospheres on Halloysite Nanotubes for “Green” Ultrahydrophobic Cotton Fabrics
Authors: Patil Namrata V. , Netravali Anil N.
Published: June 2019

This paper presents a sustainable biomimetic approach to create ultrahydrophobic cotton fabrics. Cotton fabrics are modified using biobased raw materials to create multiple scale roughness and low surface energy on their surfaces. Naturally occurring halloysite nanotubes (HNT) are modified by silanization and direct assembly of silica (SiO2) nanospheres on the surface of HNTs. HNTs “decorated” with SiO2 nanospheres are covalently bonded onto the surface of cotton fabrics, creating a durable multiple scale surface roughness. Surface modified cotton fabrics are further grafted with fatty acid without using any solvent, via esterification. The combination of the hierarchical roughness pattern created on the surface through modified HNT, and fatty acid treatment results in ultrahydrophobic fabrics with water contact angles (WCAs) above 150°. Surface topographies of modified HNT particles and chemical changes are fully characterized. Attenuated total reflectance Fourier‐transform infrared and WCA studies are used to confirm the grafting of modified HNT particles and aliphatic fatty chains on surface of fabrics. The ultrahydrophobic cotton fabrics washed for five standard laundry cycles (25 home washings) show that the ultrahydrophobicity is durable. Moreover, the ultrahydrophobic fabrics are oleophilic, making them suitable for use in oil–water separation, anti‐biofouling and packaging, and other applications apart from water repellent clothing.
Modulation of Heavy Metal/Ferromagnetic Metal Interface for High‐Performance Spintronic Devices
Authors: Peng Shouzhong , Zhu Daoqian , Zhou Jiaqi , Zhang Boyu , Cao Anni , Wang Mengxing , Cai Wenlong , Cao Kaihua , Zhao Weisheng
Published: June 2019

Spintronic devices such as magnetic tunnel junctions and skyrmions have attracted considerable attention due to features such as nonvolatility, high scalability, low power, and high speed. Over the past few years, innovative materials and new structures in this field have resulted in the emergence of new phenomena and exciting device performance. It has been found that the heavy metal (HM)/ferromagnetic metal (FM) interface plays an essential role in spintronic devices. Spintronic device performance can be significantly enhanced through proper modulation of this interface. Recent progress in this blooming field is reviewed with specific emphasis on the HM/FM interface. Investigations into HM/FM‐interface‐related phenomena, including perpendicular magnetic anisotropy, tunnel magnetoresistance, magnetic damping, spin–orbit torque, and Dzyaloshinskii–Moriya interaction, are put into context. Guidelines for realizing high‐performance spintronic devices are provided, and an outlook on their future research direction and potential applications is given.
Targeted Polypeptide–Microtubule Aggregation with Cucurbit[8]uril for Enhanced Cell Apoptosis
Authors: Zhang Ying‐Ming , Liu Jiang‐Hua , Yu Qilin , Wen Xin , Liu Yu
Published: June 2019

Tunable protein assemblies not only hold a dominant position in vital biological events but are also a significant theme in supramolecular chemistry. Herein, we demonstrated that the intertubular aggregation of microtubules (MTs) could be efficiently regulated by a synergistic polypeptide–tubulin interaction and host–guest complexation. The benzylimidazolium‐modified antimitotic peptide (BP) could recognize the MTs and concurrently form stable inclusion complexes with avirulent cucurbit[7]uril (CB[7]) and cucurbit[8]uril (CB[8]) in different binding stoichiometries. The self‐assembling morphology of MTs was converted from fibrous to nanoparticulate aggregates via extensive BP⊂CB[8] cross‐linkage, leading to significant cell apoptosis and tumor ablation in vivo. The targeted (BP⊂CB[8])@MT ternary assembly provides a facile supramolecular method to enhance the protein–protein interactions, which may be developed as a therapy for degenerative diseases, such as cancer.
Cation‐Controlled Formation and Interconversion of the fac/fac and mer/mer Stereoisomers of a Triple‐Stranded Helicate
Authors: Chen Xiaofei , Mevissen Christian , Huda Saskia , Göb Christian , Oppel Iris M. , Albrecht Markus
Published: June 2019

Two biscatecholester ligands with oligoether spacers were used to prepare dinuclear titanium(IV) triscatecholate based helicates. In the case of Li4[(1/2)3Ti2], “classical” helicates with three internally bound Li+ ions and syn‐oriented ligands in the complex units (fac/fac isomer) were obtained. In the case of the sodium salt Na4[(2)3Ti2], a different homochiral dinuclear triple‐stranded helicate with two internally bound Na+ ions was formed. The complex units are anti‐configured, and two of the ligand spacers are connecting internal with external positions of the helicate (mer/mer isomer). Removal of the sodium ions and addition of lithium ions leads to the switching from one topology to the other with an expanded helicate [(2)3Ti2]4− as an intermediate. Switching back to the “non‐classical” helicate cannot be observed because severe structural rearrangements would be required.
Dual‐Controlled Macroscopic Motions in a Supramolecular Hierarchical Assembly of Motor Amphiphiles
Authors: Leung Franco King‐Chi , Kajitani Takashi , Stuart Marc C. A. , Fukushima Takanori , Feringa Ben L.
Published: June 2019

Three‐dimensional unidirectionally aligned and responsive supramolecular hierarchical assemblies have much potential in adaptive materials for biomedical and soft actuator applications. However, to achieve systematical control of the motion of stimuli‐responsive materials by orthogonal external stimuli and to complete a series of complicated tasks remains a grand challenge. Herein, we demonstrate a novel designed hybrid supramolecular assembly of molecular motor amphiphiles that also serves as a template for iron nanoparticles growth, and as a consequence this soft hybrid material is orthogonally controlled by dual light/magnetic stimuli. Macroscopic motor amphiphile strings, decorated with iron nanoparticles, provide fast response photoactuations and magnet induced movements that allows a precisely controlled cargo transport process.
An ethical analysis of how ESL teachers construct their professional identities through the use of information technology in teaching
Authors: Gu Mingyue M. , Lai Chun
Published: June 2019

While there is growing recognition of the mutually shaping relationship between teaching with information technology (IT) and teachers’ beliefs, skills and self‐efficacy, there has been a paucity of research attention on the construction of teacher identity during actual IT‐assisted in‐class teaching and out‐of‐class networking with students, in a full institutional and social context. This study investigates how a group of secondary school English as a second language (ESL) teachers regulated their teaching and practices and constructed their identities in relation to governmental requirements for the use of IT in teaching. Teachers from seven government‐subsidised schools in Hong Kong were interviewed about their experiences of using IT in teaching. We frame the reported practices of these teachers as a process of construction of identity, formed in the context of the ‘governmentality’ supporting current examination‐oriented educational policy. Observing from the perspective of what has been termed ‘governmentality’ and an ethical framework for self‐formation of personal identity makes it possible to see these teachers’ professional identities constructed through the use of IT practices within the contradictory conditions of professional/personal demands, compliance/resistance, school promotion/peer non‐cooperation, advantage/disadvantage in use of IT, use of IT/content and pedagogical knowledge. This study has implications for developing a more supportive and rational environment for the use of IT in teaching, in which more autonomy and identity options—rather than constraints—can be provided for teachers in the digital era. This study also informs practitioners and policy makers in other educational settings experiencing a similar IT boom in teaching.
Determination and tissue distribution studies of dantrolene sodium with hydroxypropyl‐β‐cyclodextrin in rat tissue by HPLC/MS/MS
Authors: Liu Ruixue , Chen Yu , Zhao Shen , Zhao Min , Zhao Chunjie , Wang Miao
Published: June 2019

The established analytical method for determining the concentration of dantrolene sodium (Da) in rat tissues by HPLC/MS/MS technique was successfully applied to tissue distribution studies of Da in rats. Tissue homogenate samples were pretreated by protein precipitation with pre‐cooled methanol. Chromatographic separation was achieved on an Acquity HPLC column (Kromat Universil XB‐C18, 2.1 × 150 mm, 3 μm). Mass spectrometry was conducted with an electrospray ionization interface in negative ionization mode and multiple reaction monitoring was used for quantitative analysis. The results showed that Da was rapidly and widely distributed in tissues and reached the maximum concentration within 0.5 h in all tissues after oral administration of Da–hydroxypropyl‐β‐cyclodextrin (DHC). It was then metabolized by liver and finally excreted from kidney,which indicated that DHC inclusion complex has better absorption and higher oral bioavailability than Da. The results also provided evidence for the safety and effectiveness of drug clinical application.
Disruptions of the olfactory and default mode networks in Alzheimer's disease
Authors: Lu Jiaming , Yang Qing X. , Zhang Han , Eslinger Paul J. , Zhang Xin , Wu Sichu , Zhang Bing , Zhu Bin , Karunanayaka Prasanna R.
Published: June 2019

Introduction

Olfactory deficits are prevalent in early Alzheimer's disease (AD) and are predictive of progressive memory loss and dementia. However, direct neural evidence to relate AD neurodegeneration to deficits in olfaction and memory is limited.

Methods

We combined the University of Pennsylvania Smell Identification Test (UPSIT) with olfactory functional magnetic resonance imaging (fMRI) to investigate links between neurodegeneration, the olfactory network (ON) and the default mode network (DMN) in AD.

Results

Behaviorally, olfactory and memory scores showed a strong positive correlation in the study cohorts. During olfactory fMRI, the ON showed reduced task‐related activation and the DMN showed reduced task‐related suppression in mild cognitive impairment (MCI) and AD subjects compared to age‐matched cognitively normal subjects.

Conclusions

The results provide in vivo evidence for selective vulnerability of ON and DMN in AD and significantly improves the viable clinical applications of olfactory testing. A network‐based approach, focusing on network integrity rather than focal pathology, seems beneficial to olfactory prediction of dementia in AD.
Biocompatible Inhibitor Based on Chitosan and Amphiphilic Peptide against Mutant Huntingtin Toxicity
Authors: Wahyuningtyas Devi , Chen Wen‐Hao , Huang Chen‐Han , He Yu‐Jung , Huang Joseph Jen‐Tse
Published: June 2019

Huntington's disease (HD) is classified as a protein‐misfolding disease correlated with the mutant Huntingtin (mHtt) protein with abnormally expanded polyglutamine (polyQ) domains. Because no effective drugs have yet been reported, attempts to develop better therapy to delay the age of onset are in urgent demand. In this study, an amphiphilic peptide consisting of negatively charged hexaglutamic acid and a stretch of decaglutamine (E6Q10) was chemically synthesized as an inhibitor against polyQ and mHtt toxicity. It is found that E6Q10 selfassembles into spherical vesicles, as shown by means of TEM, cryoelectron microscopy, and dynamic light scattering. Assembled E6Q10 prevented the polyQ‐rich peptide (KKWQ20AKK) from forming amyloid fibrils. To enable the cell‐penetration ability of E6Q10, the E6Q10⋅chitosan complex was generated. It is demonstrated that the complex penetrates cells, interferes with the mHtt oligomerization and aggregation process, and prevents mHtt cytotoxicity. By combining positively charged chitosan and amphiphilic peptides with a negatively charge moiety, a new strategy is provided to develop biocompatible and biodegradable inhibitors against mHtt toxicity.
Isoproterenol induces an increase in muscle fiber size by the proliferation of Pax7‐positive cells and in a mTOR‐independent mechanism
Authors: Bastos Úrsula Maria C. , de Andrade Rosa Ivone , Teixeira John D. , Gonçalves Graciele , Costa Manoel L. , Quintas Luis Eduardo M. , Mermelstein Claudia
Published: June 2019

β‐Adrenergic signaling regulates many physiological processes in skeletal muscles. A wealth of evidence has shown that β‐agonists can increase skeletal muscle mass in vertebrates. Nevertheless, to date, the specific role of β‐adrenergic receptors in different cell phenotypes (myoblasts, fibroblasts, and myotubes) and during the different steps of embryonic skeletal muscle differentiation has not been studied. Therefore, here we address this question through the analysis of embryonic chick primary cultures of skeletal muscle cells during the formation of multinucleated myotubes. We used isoproterenol (ISO), a β‐adrenergic receptor agonist, to activate the β‐adrenergic signaling and quantified several aspects of muscle differentiation. ISO induced an increase in myoblast proliferation, in the percentage of Pax7‐positive myoblasts and in the size of skeletal muscle fibers, suggesting that ISO activates a hyperplasic and hypertrophic muscle response. Interestingly, treatment with ISO did not alter the number of fibroblast cells, suggesting that ISO effects are specific to muscle cells in the case of chick myogenic cell culture. We also show that rapamycin, an inhibitor of the mammalian target of rapamycin signaling pathway, did not prevent the effects of ISO on chick muscle fiber size. The collection of these results provides new insights into the role of β‐adrenergic signaling during skeletal muscle proliferation and differentiation and specifically in the regulation of skeletal muscle hyperplasia and hypertrophy.
Trends in Oxygen Electrocatalysis of 3 d‐Layered (Oxy)(Hydro)Oxides
Authors: Zhao Zhenghang , Schlexer Lamoureux Philomena , Kulkarni Ambarish , Bajdich Michal
Published: June 2019

First‐row layered transition metal (oxy)(hydro)oxides (LTMOs) form an important class of earth‐abundant materials. They are well‐known as active alkaline oxygen evolution reaction (OER) catalysts,[1,5] and are also often used as metal‐ion battery anodes[6] or as metal‐air bifunctional electrodes.[7] However, their electrochemical activities, particularly for the oxygen reduction reaction (ORR), across the whole 3d‐element series remain largely unexplored. In this work, we perform a systematic screening of these catalysts for both OER and ORR using a surface edge‐site model with exposed active sites for metal double hydroxides M(OH)2, oxyhydroxides MOOH and oxides MO2. We establish OER and ORR activities and scaling relations of the whole series across +2, +3 and +4 oxidation states, and successfully reproduce the experimental activities of a few pure layered (oxy)(hydro)oxides. We predict CoOOH/CoO2 and NiOOH/NiO2 as active and stable OER catalysts. We also predict Fe(OH)2/FeOOH, Mn(OH)2/MnOOH and Co(OH)2 as active and stable ORR catalysts. This makes Co‐(oxy)(hydro)oxides only bifunctional catalyst in this series. Using linear regression, our results indicate that trends across the 3d‐series can be obtained from only a few bulk, surface and atomic type descriptors. Particularly, we identify that the number of outer d‐electrons at the surface‐active site as the most important descriptor of activity.
URJC‐1‐MOF as New Heterogeneous Recyclable Catalyst for C‐Heteroatom Coupling Reactions
Authors: Muñoz Antonio , Leo Pedro , Orcajo Gisela , Martínez Fernando , Calleja Guillermo
Published: June 2019

Guillermo Calleja and co‐workers from @urjc describe URJC‐1‐MOF as a new heterogeneous recyclable catalyst for c‐heteroatom coupling reactions

The capacity of copper‐based URJC‐1‐MOF as a MOF catalyst in cross‐coupling reactions has been evaluated, focusing on the Chan‐Lam‐Evans arylation‐type reactions on amines and alcohols without extra additives or ligands. The extraordinary chemical and structural stability of URJC‐1‐MOF and its good specific surface, make this material a promising alternative to homogeneous Cu (II) catalysts for cross‐coupling reactions. URJC‐1‐MOF showed a remarkable catalytic activity for cross‐coupling C−N and C−O reactions, higher than other heterogeneous and homogeneous copper‐based catalyst, such as CuO, HKUST‐1, Cu−MOF‐74, Cu(OAc)2 and CuSO4⋅5H2O. Moreover, its easy recovery by simple filtration and reusability in successive runs without any loss of activity and stability, demonstrates the potential of URJC‐1‐MOF as an alternative catalyst for this kind of reactions in different chemical media of industrial interest.
Long‐Term Stability of a Liquid‐Infused Coating with Anti‐Corrosion and Anti‐Icing Potentials on Al Alloy
Authors: Zhang Meiling , Chen Rongrong , Liu Qi , Liu Jingyuan , Yu Jing , Song Dalei , Liu Peili , Gao Liangtian , Wang Jun
Published: June 2019

Corrosion and surface icing severely shorten the service life of aluminum and its alloys. Herein, we synthesized wrinkled and porous, hollow, tubular SiO2 on an Al alloy, followed by fluorination with (Heptadecafluoro‐1,1,2,2‐tetradecyl) trimethoxysilane (FAS) and then infusing Krytox 100 for obtaining novel slippery liquid‐infused porous surfaces (SLIPSs). The unique structure greatly reduced the loss of lubricant due to the volatilization or subcooled condensation and thus effectively extended the life of the SLIPS. The corrosion resistance of as‐prepared SLIPS was five orders of magnitude higher than that of the bare Al alloy and did not change significantly after immersion in an NaCl solution for 93 days. The ice‐adhesion strength remained at approximately 18 kPa for the whole duration of the icing/deicing cycles. The samples exhibited a low contact angle hysteresis and superior self‐cleaning properties. In addition, we also revealed the differences in self‐cleaning and anti‐icing macroscopic phenomena of superhydrophobic surfaces (SHS) and SLIPS.
Schnelle lokale Raman‐Messung zur Untersuchung von Konzentrationsprofilen bei Mischvorgängen in Mikrokanälen
Authors: Deuerling Julian , Manser Steffen , Siber Julia , Keck Shaun , Hufnagel Thomas M. , Schmitt Lukas , Medina Isabel , Repke Jens‐Uwe , Rädle Matthias
Published: June 2019

Für die Evaluierung von Mischungsvorgängen in Mikroreaktoren ist es notwendig, diese genauer untersuchen zu können. Dazu wird ein neuartiges, optisches Messsystem vorgestellt, das die Visualisierung von mischungs‐ und diffusionslimitierten Vorgängen sowie Konzentrationsunterschieden in Fluidfilmen ermöglicht. Es besteht aus einer fokussierenden Optik mit einem Mikroskop‐Objektiv. In der Kombination mit einem Raman‐Spektrometer können so verschiedene Prozesse wie z. B. Diffusion im Mikroreaktor nicht‐invasiv gemessen und untersucht werden.
Low‐Cost‐Membranen für die Vanadium‐Redox‐Flow‐Batterie
Authors: Düerkop Dennis , Widdecke Hartmut , Schmiemann Achim , Kunz Ulrich , Schilde Carsten
Published: June 2019

Vanadium‐Redox‐Flow‐Batterien stellen eine Technologie dar, die zur Speicherung fluktuierender Energien aus Solar‐ und Windkraft eingesetzt werden kann. Um die Herstellungskosten der Batterien zur verringern, können zum Beispiel kostengünstigere Ausgangsmaterialien verwendet werden. Mithilfe von Polystyrol‐basierten Polymeren bei der Membranherstellung können Leitfähigkeiten erreiche werden, die vergleichbar mit denen von Perfluorsulfonsäuremembranen sind. Es wird eine Herstellungsmethode für diese heterogenen Membranen bestehend aus disperser und kontinuierlicher Phase präsentiert.
Experimental methods in chemical engineering: Reactors—fluidized beds
Authors: Menéndez Miguel , Herguido Javier , Bérard Ariane , Patience Gregory S.
Published: June 2019

Industry relies on fluidized beds to synthesize chemicals (acrylonitrile, maleic anhydride, titanium dioxide, vinyl chloride), combust coal, dry powders, and treat waste. Fluidized bed folklore declares that they are hard to scale‐up and the gas phase is backmixed. Commercial failures that disregard standard design criteria around powder management, gas/solids injection, and mixing reinforce this belief. However, engineers select fluidized beds for processes that are impractical with conventional technologies to achieve economies of scale for highly exothermic, endothermic, or explosive reactions, for catalysts that deactivate in seconds (or minutes), and for chemistry that requires multiple dosing cycles. Failures are more frequent for these challenging applications. For this reason, researchers study reaction kinetics in fixed beds despite internal mass transfer limitations and axial and radial temperature and concentration gradients. Fluidized bed hydrodynamics vary with powder properties (particle diameter, size distribution, density, sphericity), operating conditions (gas density, viscosity, temperature, pressure), reactor geometry (diameter, height, mass, grid geometry). The minimum fluidization velocity (Umf) is a property that identifies the transition from the fixed bed regime to the fluidized bed regime and equals the gas velocity at which the upward drag force equals the weight of the powder. At the experimental scale, fluidized beds operate isothermally, solids are completely backmixed, and the gas phase is close to plug flow (). Here, we describe the relationship between powder properties and fluidization quality, list experimental techniques, describe recent applications, and gas phase hydrodynamics and uncertainties.
Removal of heavy metals in a flow‐through vertical microbial electrolysis cell
Authors: Jugnia Louis‐B. , Manno Dominic , Hendry Meghan , Tartakovsky Boris
Published: June 2019

This work describes laboratory experiments aimed at evaluating the feasibility of removing heavy metals from metal‐contaminated water in flow‐through microbial electrolysis cells (MECs) with peat moss as a source of organic carbon. MECs were assembled in upflow glass columns containing granular activated carbon (GAC) bioelectrodes preceded by a layer of peat moss. The MECs were fed with metal‐contaminated surface water collected at a firing range. At hydraulic retention times (HRT) of 4–6 days, up to 99 % removal of Pb, Zn, Cu, and Fe was observed. The removal efficiency of Zn and Cu declined at an HRT of 1.7 days, while effluent Pb concentration remained below the detection limit for all of the HRTs tested. Metal extraction from MEC compartments showed an accumulation of metals in both the peat moss layer and the GAC cathode, i.e., the removal was achieved by a combination of anaerobic and bioelectrochemical pathways of metal reduction. A proliferation of sulphate reducing bacteria in the peat moss layer and electroactive species in GAC electrodes was confirmed by biomolecular analysis. The proposed flow‐through system, which combines sulphate‐reducing and electroactive microbial activities to achieve near‐complete metal removal, can be used for removing a broad range of heavy metals from contaminated water in a low‐cost passive flow treatment system.
Diagnosis of Alzheimer's disease with Sobolev gradient‐based optimization and 3D convolutional neural network
Authors: Goceri Evgin
Published: June 2019

Alzheimer's disease is a neuropsychiatric, progressive, also an irreversible disease. There is not an effective cure for the disease. However, early diagnosis has an important role for treatment planning to delay its progression since the treatments have the most impact at the early stage of the disease. Neuroimages obtained by different imaging techniques (for example, diffusion tensor‐based and magnetic resonance‐based imaging) provide powerful information and help to diagnose the disease. In this work, a deeply supervised and robust method has been developed using three dimensional features to provide objective and accurate diagnosis from magnetic resonance images. The main contributions are (a) a new three dimensional convolutional neural network topology; (b) a new Sobolev gradient‐based optimization with weight values for each decision parameters; (c) application of the proposed topology and optimizer to diagnose Alzheimer's disease; (d) comparisons of the results obtained from the recent techniques that have been implemented for Alzheimer's disease diagnosis. Experimental results and quantitative evaluations indicated that the proposed network model is able to achieve to extract desired features from images and provides automated diagnosis with 98.06% accuracy.
Magnetic Cell Sorting for In Vivo and In Vitro Astrocyte, Neuron, and Microglia Analysis
Authors: Holt Leanne M. , Stoyanof S. Tristan , Olsen Michelle L.
Published: June 2019

Interest in evaluating individual cellular populations in the central nervous system has prompted the development of several techniques enabling the enrichment of single‐cell populations. Herein we detail a relatively inexpensive method to specifically isolate neurons, astrocytes, and microglia from a mixed homogenate utilizing magnetic beads conjugated to cell‐type specific antibodies. We have used this technique to isolate astrocytes across development and into late adulthood. Finally, we detail the utilization of this technique in novel astrocyte and astrocyte/neuron co‐culture paradigms. © 2019 by John Wiley & Sons, Inc.
Controllable Synthesis of Iron Sulfide/CNT Nanocomposites in Solvothermal System
Authors: Yang Sheng , Huang Peng , Duan Meng , Li Yongying , Gao Guo
Published: June 2019

Iron sulfide (FeS2 and Fe7S8) has been considered as one of the promising electrode materials in the field of solar cell and lithium ion battery owing to their unique properties. Herein a facile solvothermal method is reported for preparing iron sulfide/carbon nanotube (CNT) nanocomposites with desired structure and composition. FeS2 nanoparticles can be successfully loaded on the surface of CNT, and the FeS2 nanoparticles uniformly distribute along the CNT. With the assistance of polyvinylpyrrolidinone (PVP), flower‐like Fe7S8@CNT precursor and flower‐like Fe7S8 precursor can be obtained, respectively. When the flower‐like precursors are annealed in the tube furnace with Ar atmosphere, the diameter of the samples decrease from micron level (≈1 µm) to submicron‐level (200–400 nm).
Chromium(III) and Chromium(II) Phenolate Complexes with Bulky Alkylcyclopentadienyl Ligands
Authors: Smytschkow Igor , Gidt Wjatscheslaw , Kunz Christoph , Sun Yu , Langer Jens , Oelkers Benjamin , Böttcher Tobias , Sitzmann Helmut
Published: June 2019

The chromium(II) tricarbonyl methyl complex [Cp′′′Cr(CO)3CH3] (1, Cp′′′ = η5‐C5H2tBu3‐1,2,4) was obtained from chromium hexacarbonyl, NaCp′′′, and methyl iodide. 1 was found to establish an equilibrium with the dicarbonyl acetyl isomer [Cp′′′Cr(CO)2(COCH3)] in solution via reversible, slightly endothermic methyl migration from chromium to a carbonyl ligand with ΔH ca. 3.6 kJ/mol and Ea ca. 49.5 kJ/mol. Phosphorus pentachloride oxidized 1 to the green, dinuclear tetrachloro complex [Cp′′′CrCl(µ‐Cl)]2 (2), which was crystallized as the blue‐green chromium(III) half sandwich complex [Cp′′′CrCl2(THF)] (3) in the presence of tetrahydrofuran vapor. Attempted sublimation of the known chromium(II) iodo complex [4CpCr(µ‐I)]2 resulted in a redox reaction with formation of the chromium(III) iodo dimer [4CpCrI(µ‐I)]2, whose tri(tert‐butyl)cyclopentadienyl derivative [Cp′′′CrI(µ‐I)]2 (4) could also be prepared by oxidation of [Cp′′′Cr(µ‐I)]2 with iodine. The chromium(III) bis(2,6‐diisopropylphenolate) complex [4CpCr(OC6H3iPr2‐2,6)2] (5) was obtained from chromium trichloride in a one pot reaction with sodium tetraisopropylcyclopentadienide, followed by sodium 2,6‐diisopropylphenolate. The chromium(III) starting compound 2 reacted with 2,6‐diisopropylphenolate to the Cp′′′ derivative [Cp′′′Cr(OC6H3iPr2‐2,6)2] (6). The chromium(II) starting compound [Cp′′′Cr(µ‐Br)]2 afforded the phenolate‐bridged chromium(II) dimer [Cp′′′Cr(µ‐OC6H5)]2 (7) upon treatment with sodium phenolate, while the product of the analogous reaction with 2,6‐di(tert‐butyl)phenolate was the mononuclear tetrahydrofuran adduct [Cp′′′Cr(OC6H3tBu2‐2,6)(THF)] (8).
Isolation of a Relatively Air‐Stable, Bulky Silyl‐Substituted, Neutral Silicon‐Centered Radical
Authors: Holzner Richard , Kaushansky Alexander , Tumanskii Boris , Frisch Philipp , Linsenmann Fabian , Inoue Shigeyoshi
Published: June 2019

The bulky supersilyl‐substituted (tBu3Si) silicon‐centered radical 1 was synthesized and fully characterized by single‐crystal X‐ray crystallography, cyclic voltammetry (CV), and EPR spectroscopy. With its extremely sterically encumbered radical center, 1 is stable in the solid state in air for 16 hours without showing signs of decomposition. Thus 1 is the most robust trisilyl‐substituted silyl radical to date and a promising candidate for application as electrode material in organic radical batteries. Furthermore, it was found to be a strong dehalogenation reagent and therefore might find application in organic syntheses.