bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Unsymmetrical Bisindolylmethanes by Reaction of Indolylmagnesium Bromides with Sulfonyl Indoles
Authors: Yuan Lixia , Palmieri Alessandro , Petrini Marino 
Published: January 2020

AbstractSulfonyl indoles are widely recognized as alkylideneindolenine precursors amenable to provide functionalized indole derivatives upon reaction with nucleophiles. In this paper reaction of sulfonyl indoles with indolylmagnesium bromides is used to access unsymmetrical bisindolylmethanes. The target compounds are obtained in satisfactory yields starting from a wide range of substrate/reagent combinations. The utilization of pyrrolylmagnesium bromides for the same reaction also affords the expected adducts albeit in moderate yield.magnified image
Modulation of Synaptic Plasticity Mimicked in Al Nanoparticle‐Embedded IGZO Synaptic Transistor
Authors: Kim Jeehoon , Kim Younghun , Kwon Ojun , Kim Taehyeon , Oh Seyoung , Jin Soeun , Park Woojin , Kwon Jung‐Dae , Hong Seung‐Woo , Lee Chang‐Sik , Ryu Ho‐Yong , Hong Seoksu , Kim Jaehoon , Heo Tae‐Young , Cho Byungjin 
Published: January 2020

AbstractDiverse artificial synapse structures and materials are widely proposed for neuromorphic hardware systems beyond von Neumann architecture owing to their capability to mimic complex information processing tasks such as image recognition, natural language processing, and learning. Nevertheless, temporal and spatial randomness in the movement of ion and electron particles that exist in materials usually prevents the solid‐state‐based synaptic devices from enabling the reliable modulation of synaptic plasticity. An aluminum nanoparticle (Al NP)‐embedded indium gallium zinc oxide (IGZO) synaptic transistor whose spike peak level and conductance change can be precisely modulated by the density of Al NPs within the IGZO channel is demonstrated. Essential synaptic functions including excitatory or inhibitory postsynaptic current, paired pulse facilitation, and short‐term potentiation or depression are also thoroughly emulated in the synaptic transistor device with the most optimized Al NP density: IGZO:Al NPs (6 nm). Moreover, controllable switching from short‐term to long‐term memory regimes essential for a learning task is demonstrated. Simulation results prove that this transistor can provide a decent recognition accuracy for neuromorphic computing. Indeed, the integrated IGZO:Al NP synaptic circuit with the effective synaptic plasticity will facilitate the implementation of a reconfigurable neuromorphic computing system.
Ligand Tailoring Oxide Colloidal Quantum Dots for Silicon‐Integrated Ultraviolet Photodiode
Authors: Lin Richeng , Kan Hao , Zheng Wei , Huang Feng 
Published: January 2020

AbstractIn the past, benefiting from the mature micro‐technologies of crystalline‐silicon (c‐Si), c‐Si electronic and optoelectronic devices have brought revolutionary convenience to daily lives, with sensitive visible and near‐infrared photodetectors, the basic device in cameras for visible spectroscopy and color imaging, as an example. However, the sensitivity of all‐Si photodetectors cannot meet the needs of deep‐ultraviolet (DUV) detection with important applications in spectral imaging analysis. Based on this circumstance, a 0D–3D silicon‐integrated photodiode is presented to obtain highly sensitive DUV detection. A vertically stacked graphene/GAO/Si back‐to‐back photodiode has high photoresponsivity (0.165 A/W and EQE ≈ 80.2% at 0 V bias, 7.42 A/W and EQE ≈ 3611% at −1 V bias) and fast response speed (3 ms) under DUV illumination by using composite modified wide‐band‐gap oxide colloidal quantum dots as the DUV sensitive layer. The performance of the detector is successfully verified by DUV imaging with a single‐point‐detection imaging system.
Let It Catch: A Short‐Branched Protein for Efficiently Capturing Polysulfides in Lithium–Sulfur Batteries
Authors: Chen Min , Li Chunhui , Fu Xuewei , Wei Wei , Fan Xin , Hattori Andrew , Chen Zhiping , Liu Jin , Zhong Wei‐Hong 
Published: January 2020

AbstractUncovering the key contributions of molecular details to capture polysulfides is important for applying suitable materials that can effectively restrain the shuttle effect in advanced lithium–sulfur batteries. This is particularly true for natural biomolecules with substantial structural and compositional diversities strongly impacting their functions. Here, natural gelatin and zein proteins are first denatured and then adopted for fabrication of nanocomposite interlayers via functionalization of carbon nanofibers. From the results of experiment and molecular dynamic simulations, it is found that the lengths of the sidechains on the two proteins play critical roles. The short‐branched gelatin shows significantly stronger adsorption of polysulfides, as compared with zein comprising many long‐chain residues. The gelatin‐based interlayer, along with its good porous structures/electrical conductivity, greatly suppresses the shuttle effect and yields exceptional electrochemical performance. Furthermore, the implementation of proteins as functional binder additives further supports the finding that gelatin enables stronger polysulfide‐trapping. As a result, high‐loading sulfur cathodes (9.4 mg cm−2) are realized, which deliver a high average areal capacity of 8.2 mAh cm−2 over 100 cycles at 0.1 A g−1. This work demonstrates the importance of sidechain length in capturing polysulfides and provides a new insight in selecting and design of desired polysulfide‐binding molecules.
A Flexible Solid Electrolyte with Multilayer Structure for Sodium Metal Batteries
Authors: Ling Wei , Fu Na , Yue Junpei , Zeng Xian‐Xiang , Ma Qiang , Deng Qi , Xiao Yao , Wan Li‐Jun , Guo Yu‐Guo , Wu Xiong‐Wei 
Published: January 2020

AbstractSolid electrolytes (SEs) can potentially address the inherent safety problems of conventional organic liquid electrolytes. However, their low ionic conductivity and large interfacial resistance limit the practical applications of SEs. Here, a flexible solid electrolyte with a multilayer structure is fabricated by the UV curing of an interpenetrating network of poly(ether‐acrylate) (ipn‐PEA) in the Na3Zr2Si2PO12/poly(vinylidene fluoride‐hexafluoropropylene) porous skeleton (NZSP/PVDF‐HFP), exhibiting a high Na+ transference number of 0.63 and a suitable ionic conductivity of above 10−4 S cm−1 at 60 °C. In addition, due to the unique structure of the internal rigidity and external flexibility, the composite solid electrolyte can effectively mitigate interfacial ion transfer issues while guaranteeing a certain mechanical strength, and largely inhibiting the formation of dendrite and dead sodium. The solid sodium metal batteries using Na3V2(PO4)3 (NVP) as a cathode possess a discharge capacity of 85 mA h g−1 after 100 cycles at 0.5 C, and achieve above 90% of capacity retention rate during 100 cycles at 0.1 C for Na2/3Ni1/3Mn1/3Ti1/3O2 (NTMO) at 60 °C. The flexible solid electrolyte with multilayer structure shows a great advantage for managing the ionic conductivity and interface resistance problem, suggesting a promise as a practical sodium metal battery.
Genetic evaluation including exome sequencing of two patients with Gomez‐Lopez‐Hernandez syndrome: Case reports and review of the literature
Authors: Lindsay Faith , Anderson Ilse , Wentzensen Ingrid M. , Suhrbier David , Stevens Cathy A. 
Published: January 2020

AbstractRhombencephalosynapsis (RES) is a rare congenital anomaly of the hindbrain characterized by fusion of the cerebellar hemispheres, cerebellar peduncles, and dentate nuclei with vermian absence or hypogenesis. This anomaly can be isolated or part of a larger spectrum of cerebral abnormalities. At least 90 cases are described in the literature and it has been associated with VACTERL and Gomez‐Lopez‐Hernandez syndrome (GLHS). The most common congenital syndrome associated with RES is GLHS, a rare presumed genetic disorder with over 30 cases thus far described in the literature. No genetic cause has been identified for RES or GLHS. We report two probands diagnosed with GLHS based on clinical criteria. Each proband had RES and bi‐parietal scalp alopecia as well as neurologic findings and phenotypic features including trigeminal anesthesia, borderline hypertelorism, midface retrusion, and motor delay. Oliginucleotide‐SNP microarray on the male proband revealed a 1.05 Mb copy duplication of uncertain clinical significance at 15q21.3 while oligonucleotide‐SNP microarray for the female proband did not reveal any abnormalities. Exome sequencing (ES) was performed on both patients and did not identify any variants that could explain the GLHS phenotype. To our knowledge, these are the first two patients with GLHS described in the literature to undergo ES. Both patients had mild neurologic manifestations requiring physical therapy in early life without known diagnostic cause. Patients found to have scalp alopecia or trigeminal anesthesia with gross motor delay should be evaluated for RES or GLHS as well as screened for associated syndromes and have a complete neurodevelopmental evaluation.
Divergent Strain‐Release Amino‐Functionalization of [1.1.1]Propellane with Electrophilic Nitrogen‐Radicals
Authors: Kim Ji Hye , Ruffoni Alessandro , Al‐Faiyz Yasair S. S. , Sheikh Nadeem S. , Leonori Daniele 
Published: January 2020

AbstractHerein we report the development of a photocatalytic strategy for the divergent preparation of functionalized bicyclo[1.1.1]pentylamines. This approach exploits, for the first time, the ability of nitrogen‐radicals to undergo strain‐release reaction with [1.1.1]propellane. This reactivity is facilitated by the electrophilic nature of these open‐shell intermediates and the presence of strong polar effects in the transition‐state for C−N bond formation/ring‐opening. With the aid of a simple reductive quenching photoredox cycle, we have successfully harnessed this novel radical strain‐release amination as part of a multicomponent cascade compatible with several external trapping agents. Overall, this radical strategy enables the rapid construction of novel amino‐functionalized building blocks with potential application in medicinal chemistry programs as p‐substituted aniline bioisosteres.
Total Synthesis of Tiacumicin B: Implementing Hydrogen Bond Directed Acceptor Delivery for Highly Selective β‐Glycosylations
Authors: Norsikian Stéphanie , Tresse Cedric , François‐Eude Marc , Jeanne‐Julien Louis , Masson Guillaume , Servajean Vincent , Genta‐Jouve Grégory , Beau Jean‐Marie , Roulland Emmanuel 
Published: January 2020

AbstractA total synthesis of tiacumicin B, a natural macrolide whose remarkable antibiotic properties are used to treat severe intestinal infections, is reported. The strategy is in part based on the prior synthesis of the tiacumicin B aglycone, and on the decisive use of sulfoxides as anomeric leaving groups in hydrogen‐bond‐mediated aglycone delivery (HAD). This new HAD variant permitted highly β‐selective rhamnosylation and noviosylation. To increase convergence, the rhamnosylated C1–C3 fragment thus obtained was anchored to the C4–C19 aglycone fragment by adapting the Suzuki–Miyaura cross‐coupling used for the aglycone synthesis. Ring‐size‐selective macrolactonization provided a compound engaged directly in the noviolysation step with virtually total β selectivity. The final efficient removal of all the protecting groups provided synthetic tiacumicin B.
A redescription of the late Carboniferous trematopid Actiobates peabodyi from Garnett, Kansas
Authors: Gee Bryan M. , Reisz Robert R. 
Published: January 2020

AbstractDissorophoids are a diverse clade of predominantly Permo‐Carboniferous temnospondyls with a wide geographic distribution and broad ecological diversity. Each of the various dissorophoid clades first appears in the late Carboniferous, but their records are relatively sparse and fragmentary compared to those of the early Permian when dissorophoids reach their peak diversity and distribution, particularly in terrestrial environments where they are by far the most taxonomically diverse clade of non‐amniote tetrapods. This provides an impetus for further study of the late Carboniferous terrestrial dissorophoids in order to contextualize the early stages in the clade's radiation into terrestrial ecosystems. Here we present a redescription of the late Carboniferous trematopid Actiobates peabodyi from Kansas, USA, which is represented by a nearly complete skeleton and which represents the earliest occurrence of trematopids in North America. Only the skull was previously described, and the taxon has been largely overlooked in the context of early terrestrial dissorophoid evolution. Here, we provide an updated cranial description, the first postcranial description, and a discussion of the position of A. peabodyi in the context of olsoniform evolution. Our most significant finding is the characterization of postcranial anatomy that is highly similar to that of later trematopid taxa. This high degree of conservatism indicates that the earliest trematopids were already well adapted for terrestrial environments, and post‐Carboniferous radiations of olsoniforms may be attributed to an expansion of the dryland terrestrial environments in which these taxa already thrived, rather than to novel acquisition of adaptive features later in the clade's evolution.
3′‐(4‐(Benzyloxy)phenyl)‐1′‐phenyl‐5‐(heteroaryl/aryl)‐3,4‐dihydro‐1′H,2H‐[3,4′‐bipyrazole]‐2‐carboxamides as EGFR kinase inhibitors: Synthesis, anticancer evaluation, and molecular docking studies
Authors: Nawaz Farah , Alam Ozair , Perwez Ahmad , Rizvi Moshahid A. , Naim Mohd. J. , Siddiqui Nadeem , Pottoo Faheem H. , Jha Mukund 
Published: January 2020

AbstractPyrazoline‐linked carboxamide derivatives were designed, synthesized, and evaluated for potential epidermal growth factor receptor (EGFR) kinase inhibition, anticancer activity, and apoptotic and cardiomyopathy toxicity. Compounds 6m and 6n inhibit EGFR kinase at a concentration of 6.5 ± 2.91 and 3.65 ± 0.54 µM, respectively. Some of these compounds showed effects on proliferation, which were also then evaluated against four different human cancer cell lines, that is, MCF‐7 (breast cancer), A549 (non‐small‐cell lung tumor), HCT‐116 (colon cancer), and SiHa cells (cancerous tissues of the cervix uteri). The results showed that certain synthetic compounds showed significant inhibitor activity; compounds 6m and 6n were more cytotoxic than doxorubicin against A549 cancer cells, with IC50 values of 10.3 ± 1.07 and 4.6 ± 0.57 µM, respectively. Additionally, compounds 6m and 6n induced apoptosis in A549 cancer cells, as evidenced by 4′,6‐diamidino‐2‐phenylindole (DAPI) staining and phase‐contrast microscopy. Potency to induce apoptosis by compound 6n was further confirmed by fluorescence‐activated cell sorting using Annexin V‐FITC and propidium iodide labeling. Compound 6n showed normal cardiomyocytes with no marked sign of pyknotic nuclei in cardiomyopathy and also normal histological appearance of the renal cortex when compared with that of control. Results of molecular docking studies suggested that compounds 6m and 6n can bind to the hinge region of the adenosine triphosphate‐binding site of EGFR kinase, like the standard drug erlotinib. Therefore, the present study suggests that compounds 6m and 6n have potent in vitro antitumor activities against the human non‐small‐cell lung tumor cell line A549, which can be further explored in other cancer cell lines and in animal studies.
Chalcone hybrids and their antimalarial activity
Authors: Cheng Peng , Yang Linlin , Huang Xiaodan , Wang Xuejun , Gong Maoqing 
Published: January 2020

AbstractMalaria, one of the most striking, re‐emerging infectious diseases caused by the genus Plasmodium, places a huge burden on global healthcare systems. A major challenge in the control and eradication of malaria is the continuous emergence of increasingly widespread drug‐resistant malaria, creating an urgent need to develop novel antimalarial agents. Chalcone derivatives are ubiquitous in nature and have become indispensable units in medicinal chemistry applications due to their diverse biological profiles. Many chalcone derivatives demonstrate potential in vitro and in vivo antimalarial activity, so chalcone could be a useful template for the development of novel antimalarial agents. This review covers the recent development of chalcone hybrids as antimalarial agents. The critical aspects of the design and structure–activity relationship of these compounds are also discussed.
Heterometallic Triply‐BridgingBis‐Borylene Complexes
Authors: Bag Ranjit , Kar Sourav , Saha Suvam , Gomosta Suman , Raghavendra Beesam , Roisnel Thierry , Ghosh Sundargopal 
Published: January 2020

AbstractTriply‐bridgingbis‐{hydrido(borylene)} andbis‐borylene species of groups 6, 8 and 9 transition metals are reported. Mild thermolysis of [Fe2(CO)9] with anin situproduced intermediate, generated from the low‐temperature reaction of [Cp*WCl4] (Cp*=η5‐C5Me5) and [LiBH4⋅THF] afforded triply‐bridgingbis‐{hydrido(borylene)}, [(μ3‐BH)2H2{Cp*W(CO)2}2{Fe(CO)2}] (1) andbis‐borylene, [(μ3‐BH)2{Cp*W(CO)2}2{Fe(CO)3}] (2). The chemical bonding analyses of1show that the B−H interactions inbis‐{hydrido (borylene)} species is stronger as compared to the M−H ones. Frontier molecular orbital analysis shows a significantly larger energy gap between the HOMO‐LUMO for2as compared to1. In an attempt to synthesize the ruthenium analogue of1, a similar reaction has been performed with [Ru3(CO)12]. Although we failed to get thebis‐{hydrido(borylene)} species, the reaction afforded triply‐bridgingbis‐borylene species [(μ3‐BH)2{WCp*(CO)2}2{Ru(CO)3}] (2′), an analogue of2. In search for the isolation of bridgingbis‐borylene species of Rh, we have treated [Co2(CO)8] withnido‐[(RhCp*)2(B3H7)], which afforded triply‐bridgingbis‐borylene species [(μ3‐BH)2(RhCp*)2Co2(CO)4(μ‐CO)] (3). All the compounds have been characterized by means of single‐crystal X‐ray diffraction study;1H,11B,13C NMR spectroscopy; IR spectroscopy and mass spectrometry.
Luminescent Coordination Polymers Constructed from a Flexible, Tetradentate Diisopyrazole Ligand and Copper(I) Halides
Authors: Yoneda Tomoki , Kasai Chika , Manabe Yumehiro , Tsurui Makoto , Kitagawa Yuichi , Hasegawa Yasuchika , Sarkar Parantap , Inokuma Yasuhide 
Published: January 2020

AbstractOne‐ and two‐dimensional coordination polymers composed of a structurally flexible, tetradentate diisopyrazole ligand and copper(I) halides were synthesized as crystalline solids. Complexation with copper(I) chloride or bromide resulted in the formation of infinite coordination chains through connecting each diisopyrazole ligand with two copper(I) ions in a trigonal planar coordination geometry. Contrarily, the combination of a diisopyrazole ligand and copper(I) iodide gave a two‐dimensional coordination network comprising Cu4I4 units with stair‐step type geometry and diisopyrazoles that acted as both tetradentate and bidentate bridging ligands. All the coordination polymers exhibited visible photo‐emission upon UV irradiation, and the Cu4I4 complex showed thermochromic behavior.
Stimuli‐Responsive Naphthalene Diimide as Invisible Ink: A Rewritable Fluorescent Platform for Anti‐Counterfeiting
Authors: Kalita Anamika , Malik Akhtar Hussain , Sarma Neelotpal Sen 
Published: January 2020

AbstractHerein, we report an approach to combat counterfeiting and storage of valuable information based on the solid‐state fluorescence switching behavior of isoniazid functionalized naphthalene diimide (ISO_NDI) in response to an external stimuli (i. e., HCl vapor). The unique feature of ISO_NDI is further utilized to develop an invisible ink (ISO_NDI‐PVA) with commercial polymer polyvinyl alcohol (PVA). A solid‐state fluorescence recovery was observed while loading with HCl vapors. This exclusive property of the material could be applied directly as a security ink for confidential data storage purpose. Based on above strategy, we successfully realized the rewritable application by using ISO_NDI‐PVA ink and confirm its practical efficacy on various substrates by creating different patterns. The solid‐state fluorescence switching behavior of ISO_NDI‐PVA ink exhibited reversible on/off signal for multiple cycles under the influence of HCl/NH3 vapors. Mechanistic investigation supports a clear participation of intermolecular charge transfer (ICT) phenomenon in the solid‐state fluorescence switching property. The ease of fabricating the ink with invisible to visible characteristics in response to HCl vapors provides new opportunities for exploring the application of ISO_NDI‐PVA as invisible ink for targeted security applications.
Virtual feed drive system of machine tools development and applications in diagnosis and servo‐tuning
Authors: Lee Ko‐Fei , Lee Ching‐Hung 
Published: January 2020

AbstractThis paper proposes a servo‐tuning system for five‐axis machine tools using a virtual feed drive system. The feed drive systems were first modeled to include the influence of friction and backlash. The particle swarm optimization (PSO) algorithm was adopted to identify and estimate the optimal system parameters. Therefore, the virtual system can be used to comprehend the influence of servo parameters on machining performance. The proposed approach was verified using the QC20‐W wireless ballbar to measure the results of the circular test. The experimental results indicate that our proposed approach can improve the rounding error by 21% and mismatch between the feed axes by 16%. In addition, based on parameter variations, such as variations in bandwidth, resonance frequency, and contour error, we propose methods to diagnose online contouring errors.
Reciprocal Influences Between Parent Input and Child Language Skills in Dyads Involving High‐ and Low‐Risk Infants for Autism Spectrum Disorder
Authors: Choi Boin , Nelson Charles A. , Rowe Meredith L. , Tager‐Flusberg Helen 
Published: January 2020

We examined the language input of parents of infants at high and low familial risk for autism spectrum disorder (ASD) and investigated reciprocal associations between parent input and child language skills in the first 2 years of life. Parent‐infant dyads (high‐risk: n = 53; low‐risk: n = 33), 19 of whom included an infant later diagnosed with ASD, were videotaped during free play interactions at 12, 18, and 24 months. Measures of parent input were derived from parent–child interactions. Children's language skills were assessed using the Mullen Scales of Early Learning at 12, 18, and 24 months. Results suggested that (a) parents of high‐ and low‐risk infants produced similar word tokens, word types, and proportions of contingent verbal responses, but parents of high‐risk infants used shorter mean length of utterances (MLU) than parents of low‐risk infants at 18 and 24 months; (b) parents' MLU at 18 months was positively associated with their infants' language at the subsequent visit after 6 months, regardless of group; and (c) infants' language at 18 months was positively associated with parents' MLU at the subsequent visit after 6 months in the high‐risk group only. These findings contribute to our understanding of the mechanisms underlying early language learning of high‐risk infants who have an increased risk for language delays and deficits. Autism Res 2020, 13: 1168‐1183. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.Lay SummaryParents provide an important source of language input to their children. In this study, we looked at parent input to infants at high‐ and low‐risk for autism spectrum disorder and relations between parent input and child language in the first 2 years of life. We found that parents of high‐ and low‐risk infants provided similar quantity and quality of input, except shorter average length of utterances at 18 and 24 months in the high‐risk group. Also, there were bidirectional relations between parent input and child language at 18 and 24 months in high‐risk pairs, suggesting that parents and children collectively shape the early language environment.