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Brassica napus (rapeseed) is a recent allotetraploid plant and the second most important oilseed crop worldwide. The origin of B. napus and the genetic relationships with its diploid ancestor species remain largely unresolved. Here, chloroplast DNA (cpDNA) from 488 B. napus accessions of global origin, 139 B. rapa accessions and 49 B. oleracea accessions were populationally resequenced using Illumina Solexa sequencing technologies. The intraspecific cpDNA variants and their allelic frequencies were called genomewide and further validated via EcoTILLING analyses of the rpo region. The cpDNA of the current global B. napus population comprises more than 400 variants (SNPs and short InDels) and maintains one predominant haplotype (Bncp1). Whole-genome resequencing of the cpDNA of Bncp1 haplotype eliminated its direct inheritance from any accession of the B. rapa or B. oleracea species. The distribution of the polymorphism information content (PIC) values for each variant demonstrated that B. napus has much lower cpDNA diversity than B. rapa; however, a vast majority of the wild and cultivated B. oleracea specimens appeared to share one same distinct cpDNA haplotype, in contrast to its wild Cgenome relatives. This finding suggests that the cpDNA of the three Brassica species is well differentiated. The predominant B. napus cpDNA haplotype may have originated from uninvestigated relatives or from interactions between cpDNA mutations and natural/artificial selection during speciation and evolution. These exhaustive data on variation in cpDNA would provide fundamental data for research on cpDNA and chloroplasts. [ABSTRACT FROM AUTHOR]

Designing highly efficient electrocatalysts for oxygen evolution reaction (OER) plays a key role in the development of various renewable energy storage and conversion devices. In this work, we developed metallic Co4Nporous nanowire arrays directly grown on flexible substrates as highly active OER electrocatalysts for the first time. Benefiting from the collaborative advantages of metallic character, 1D porous nanowire arrays, and unique 3D electrode configuration, surface oxidation activated Co4N porous nanowire arrays/carbon cloth achieved an extremely small overpotential of 257 mV at a current density of 10 mAcm-2, and a low Tafel slope of 44 mVdec-1 in an alkaline medium, which is the best OER performance among reported Co-based electrocatalysts to date. Moreover, in-depth mechanistic investigations demonstrate the active phases are the metallic Co4N core inside with a thin cobalt oxides/hydroxides shell during the OER process. Our finding introduces a new concept to explore the design of highefficiency OER electrocatalysts. [ABSTRACT FROM AUTHOR]

The rhodium-catalyzed asymmetric N-selective coupling of pyrazole derivatives with terminal allenes gives access to enantioenriched secondary and tertiary allylic pyrazoles, which can be employed for the synthesis of medicinally important targets. The reaction tolerates a large variety of functional groups and labelling experiments gave insights into the reaction mechanism. This new methodology was further applied in a highly efficient synthesis of JAK 1/2 inhibitor ( R)-ruxolitinib. [ABSTRACT FROM AUTHOR]

We study errors-in-variables problems when the response is binary and instrumental variables are available. We construct consistent estimators through taking advantage of the prediction relation between the unobservable variables and the instruments. The asymptotic properties of the new estimator are established and illustrated through simulation studies. We also demonstrate that the method can be readily generalized to generalized linear models and beyond. The usefulness of the method is illustrated through a real data example. [ABSTRACT FROM AUTHOR]

ABSTRACT Hydrophobically modified polyacrylamide (HMPAM) is synthesized by a free radical micellar polymerization method with low amounts of anionic long-chain alkyl, sodium 9-(and 10)-acrylamidostearate (NaAAS), which is derived from a renewable resource material, oleic acid. In this progress, the molar ratio of Sodium dodecyl sulfate (SDS) to NaAAS is adjusted, so polymers with different lengths of the hydrophobic blocks (NH = 3 and NH = 6) are obtained. The copolymers are characterized by 1H NMR, and the polymer weight and polydispersity are determined by gel permeation chromatography. The solution behaviors of the copolymers are studied as functions of concentrations, pH, and added electrolytes by steady-flow and oscillatory experiments. The viscosities of these HMPAMs increase enormously above the critical concentration (c*). The sample with longer hydrophobic blocks exhibits better thickening effect. The rheological behaviors of aqueous solutions of HMPAMs are also investigated at different pH and brine environments. Low pH or the presence of brine promotes the intramolecular associating of hydrophobes for the both copolymers in semidilute solutions. The introduction of ionizable carboxylic group on the long hydrophobic side chain significantly influences the aggregation behaviors of the copolymers, leading to unique solution behaviors of the poly(AAm/NaAAS) copolymers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40754. [ABSTRACT FROM AUTHOR]

The rhodium-catalyzed, highly N2- and N1-selective coupling of benzotriazoles with allenes is reported. The exceptionally high N2 and N1 selectivities were achieved by using a rhodium(I)/DPEphos and rhodium(I)/JoSPOphos catalyst, respectively. This method permits the atom-economic synthesis of valuable branched N2- and N1-allylated benzotriazole derivatives and allows for preliminary studies of their reactivity. [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates the decode-and-forward two-way relaying channel without direct link and proposes a protocol based on the physical-layer network coding (PNC) protocol. The proposed protocol (termed ORT) introduces one retransmission into PNC, aiming at enhancing its outage performance. To manifest the merits of ORT, we compare it with PNC and the time-division broadcast (TDBC) protocol, in terms of outage performance, expected rate, and diversity-multiplexing tradeoff (DMT). Firstly, we derive the outage probability of the three protocols and then the expected rate. Secondly, asymptotic analysis is conducted to shed light on the diversity and coding gains. Finally, the DMT is obtained for the three protocols. The numerical results reveal the following: (i) that ORT performs better than PNC in both outage and expected rate performance when the nodes transmit with different powers. However, it has the same DMT performance with PNC; (ii) that ORT possesses improved DMT performance over TDBC whereas its expected rate is only better than the latter at medium to high signal-to-noise ratio. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An efficient methodology for synthesizing a small library of easily tunable and sterically bulky ligands for asymmetric hydroformylation (AHF) has been reported. Five groups of alkene substrates have been tested with excellent conversions, moderate-to-excellent regio- and enantioselectivities. Among the best result of the reported literature, application of ligand 1 c in the highly selective AHF of the challenging substrate 2,5-dihydrofuran yielded almost one isomer in up to 99 % conversion along with enantiomeric excesses ( ee) of up to 92 %. Highly enantioselective AHF of dihydropyrrole substrates is achieved using the same ligand, with up to 95 % ee and up to >1:50 β-isomer/α-isomer ratio. [ABSTRACT FROM AUTHOR]

Poly( L-lactide) (PLLA)/poly( D-lactide) (PDLA)/clay nanocomposites are prepared via simple melt blending method at PDLA loadings from 5 to 20 wt%. Formation of the stereocomplex crystals in the nanocomposites is confirmed by differential scanning calorimetry and wide-angle X-ray diffraction (WAXD). The internal structure of the nanocomposites has been established by using WAXD and transmission electron microscope analyses. The dispersion of clay in the PLLA/PDLA/clay nanocomposites can be improved as a result of increased intensity of shear during melt blending. The overall crystallization rates are faster in the PLLA/PDLA/clay nanocomposites than in PLLA/clay nanocomposite and increase with an increase in the PDLA loading up to 10 wt%; however, the crystallization mechanism and crystal structure of these nanocomposites remain unchanged despite the presence of PDLA. The storage modulus has been apparently improved in the PLLA/PDLA/clay nanocomposites with respect to PLLA/clay nanocomposite. Moreover, it is found that the hydrolytic degradation rates have been enhanced obviously in the PLLA/PDLA/clay nanocomposites than in PLLA/clay nanocomposite. POLYM. ENG. SCI., 54:914-924, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

New Rh‐ and Pd‐catalyzed regiodivergent and stereoselective intermolecular coupling reactions of imidazole derivatives with mono‐substituted allenes are herein reported. Using a RhI/Josiphos system, perfect regioselectivities and high enantiomeric excess were obtained, while a PdII/dppf system gave linear products with high regioselectivities and high E/Z selectivities. This method permits the atom economic synthesis of valuable branched and linear allylic imidazole derivatives. [ABSTRACT FROM AUTHOR]

A highly enantioselective Michael addition of nitroacetates to β,γ-unsaturated α-ketoesters was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields with up to 99 % ee. With these densely functionalized products, the chiral cyclic nitrones, which are important synthetic intermediates, can be obtained in one step. [ABSTRACT FROM AUTHOR]

ABSTRACT Biodegradable stereocomplex-type poly( l-lactide) (PLLA)/poly( d-lactide) (PDLA)/multiwalled carbon nanotubes (MWCNTs) nanocomposites are prepared via simple melt blending method at PDLA loadings from 5 to 20 wt %. Formation of the stereocomplex crystals in the nanocomposites is confirmed by the phase transition in the differential scanning calorimetric profiles. Field emission scanning electron microscopy observation indicates that MWCNTs are nicely dispersed in the PLLA/PDLA/MWCNTs ternary blends with 20 wt % PDLA loading due to the increased shear stress in the melt-compounding with presence of PDLA. The overall crystallization rates are faster in the PLLA/PDLA/MWCNTs nanocomposites than in PLLA/MWCNTs nanocomposite; however, the crystallization mechanism and crystal structure of these nanocomposites remain unchanged despite the presence of PDLA. The storage modulus above glass transition temperature has been apparently improved in the PLLA/PDLA/MWCNTs nanocomposites with respect to PLLA/MWCNTs nanocomposite. It is interesting to find that the hydrolytic degradation rates have been enhanced obviously in the PLLA/PDLA/MWCNTs nanocomposites than in PLLA/MWCNTs nanocomposite, which may be of great use and importance for the wider practical application of PLLA/MWCNTs nanocomposites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3919-3929, 2013 [ABSTRACT FROM AUTHOR]

Melt blending of poly(lactic acid) (PLA) and ethylene/methyl acrylate/glycidyl methacrylate terpolymer (EGA) containing relatively high-concentration epoxide groups (8 wt%) was performed to improve the toughness and crystallization of PLA. The results of nonisothermal and isothermal crystallization investigation showed that the addition of EGA accelerated the crystallization rate and increased the final crystallinity of PLA in the blends. Significant enhancement in toughness and flexibility of PLA were achieved by the incorporation of the EGA elastomer. When 20 wt% EGA added, the impact strength increased from 3.0 kJ m−2 of neat PLA to 59.8 kJ m−2 and the elongation at break increased from 4.9 to 232.0%. The failure mode changed from brittle fracture of neat PLA to ductile fracture of the blend. POLYM. ENG. SCI., 53:2498-2508, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT A novel kind of impact protective material, named as impact protective micro-gel (IPM), was synthesized via a precipitation copolymerization of a compound containing boron and silanol. Diphenylmethane diisocyanate (MDI) was introduced as the chain extender to enhance its impact protective performance. Its rheological properties and morphology were investigated. Three-dimensional (3D) spacer warp-knitted fabrics were dip-coated with the IPM made with and without use of MDI, and the impact protective performance of 3D finished fabrics was assessed by drop impact tests. The results show that the adjustment of the MDI content can adjust the real cross-linking density of the IPM due to the entanglement of polymer chains, and an appropriate cross-linking density can endow dilatant properties to the IPM samples. The results also show that the impact protective performance of 3D spacer fabrics finished with the IPM can be significantly improved. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2345-2351, 2013 [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates two-way relaying with direct link transmission. We propose to combine incremental relaying (IR) with the time division broadcast protocol (TDBC) to form a new scheme, termed TDBC-IR, to increase the spectral efficiency of TDBC. Assuming half-duplex decode-and-forward relaying, the performance of three protocols, that is, TDBC, TDBC-IR, and physical-layer network coding (PNC), are studied and compared, in terms of outage probability, expected rate (ER), and diversity-multiplexing tradeoff. First, we reveal that the outage probability performance of TDBC-IR is the same as that of TDBC and better than that of PNC. Second, we compare the ER and diversity-multiplexing tradeoff performance of the three protocols based on the derived outage probability. The numerical results reveal that (1) the ER of TDBC-IR is greater than that of TDBC and PNC in the whole signal-to-noise ratio (SNR) region, that is TDBC-IR has improved spectral efficiency performance; (2) the ER performance of TDBC is better than PNC in the low SNR region but worse in the high SNR region; (3) the maximum achievable diversity order of TDBC-IR and TDBC are both two whereas that of PNC is one; (4) the maximum achievable multiplexing gain of TDBC-IR is one, which is better than TDBC (its maximum achievable is 2/3) and achieves the maximum of PNC (its maximum achievable is one). Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ein neues metallisches 2D ‐ Material mit hoher elektrischer Leitfähigkeit (1×103 S m−1) besteht aus VSe2 ‐ Nanoschichten mit vier bis acht Se ‐ V ‐ Se ‐ Atomlagen. Es ist das erste zweidimensionale Übergangsmetalldichalkogenid mit intrinsischem Raumtemperatur ‐ Ferromagnetismus. Die Übergangstemperatur der Ladungsdichtewellen ist in den Nanoschichten auf 135 K erhöht. [ABSTRACT FROM AUTHOR]

Lithium makes it possible: The enantioselective Michael addition of aldehydes to nitroalkenes was catalyzed by the readily available proline lithium salt. Remarkably, the asymmetric Michael reaction was scaled up to 50 mmol with 23:1 d.r. and 90 % ee. [ABSTRACT FROM AUTHOR]

A highly anti-selective asymmetric Henry reaction has been developed, affording synthetically versatile β-nitroalcohols in a predominately anti-selective manner (mostly above 15:1) and excellent ee values (mostly above 95 %). Moreover, the anti-selective Henry reaction was carried out in the presence of water for the first time with up to 99 % ee. The catalytic mechanism was proposed based on the detection of the intermediates by extractive electrospray ionization mass spectrometry (EESI-MS). Furthermore, the anti adducts have been successfully transformed into the biochemically important (+)-spisulosine and a pyrroloisoquinoline derivative. [ABSTRACT FROM AUTHOR]

In this paper we present a new algorithm for accurate rendering of translucent materials under Spherical Gaussian (SG) lights. Our algorithm builds upon the quantized-diffusion BSSRDF model recently introduced in [dI11]. Our main contribution is an efficient algorithm for computing the integral of the BSSRDF with an SG light. We incorporate both single and multiple scattering components. Our model improves upon previous work by accounting for the incident angle of each individual SG light. This leads to more accurate rendering results, notably elliptical profiles from oblique illumination. In contrast, most existing models only consider the total irradiance received from all lights, hence can only generate circular profiles. Experimental results show that our method is suitable for rendering of translucent materials under finite-area lights or environment lights that can be approximated by a small number of SGs. [ABSTRACT FROM AUTHOR]

A new method for protein extraction from yeast Saccharomyces cerevisiae cells is described. This method involves the use of LiAc and NaOH to enhance the permeability of yeast cell wall prior to protein extraction with SDS-PAGE sample buffer. It was safe and efficient compared to other methods reported so far in the literature. The proteins extracted with this new method retained their immunoreactive properties and are suitable for most applications in molecular biology studies. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a study which prepared polyacrylamide (PAM) aqueous dispersions, with the use of poly(sodium acrylic acid) (PAANa) as stabilizer. The study performed acrylamide's dispersion polymerization in aqueous solution of ammonium sulfate (AS). Results suggest the stability of the PAM aqueous dispersions during long storage.

Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal neurodegenerative disorders caused by an infectious agent termed a prion, which can convert normal cellular prion protein (PrPC) into a pathologically misfolded isoform (PrPSc). Taking advantage of protein misfolding cyclic amplification (PMCA), a series of experiments was conducted to investigate the possible influences of pyridine nucleotides on the propagation activities of hamster-adapted scrapie agents 263K and 139A in vitro using normal hamster brain homogenates and recombinant hamster PrP as the substrates. The results showed that PrPSc from both scrapie agent 263K- and 139A-infected brains propagated more efficiently in PMCA with the addition of reduced NADPH, showing an obvious dose-dependent enhancement. Reduced NADH also prompted PrPSc propagation, whereas NADP, NAD and vitamin C failed. Moreover, following incubation with NADPH, recombinant hamster PrP could be efficiently converted into the proteinase K-resistant form when exposed to the trace of PrPSc from infected hamsters. Our data provide evidence that the reduced pyridine nucleotide plays an important role in the propagation of prion and this process seems to target PrPC molecules. [ABSTRACT FROM AUTHOR]

The article highlights a study which examined the self-assembly and phase behavior of copolymers of N-vinylformamide and acrylic acid under highly acidic situations. Under highly acidic conditions, the poly[(N-vinylformamide-co-(acrylic acid)] copolymers with a moderate content of N-vinylformamide showed complex phase behaviors. The particle size and the temperature-responsive behavior of the copolymers were influenced by the amount of salt and excess acid.

The article discusses the results of a study on the fabrication and characteristics of interpenetrating polymer network (IPN) films consisting of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) for use in drug delivery. The IPN films were obtained by radical solution polymerization of vinyl alcohol and acrylic acid. The increase in PAA content resulted to an increase in swelling ratio. The films have homogeneous morphology showing the compatibility and miscibility between PAA and PVA.

Farnesyltransferase (FT) inhibitors can suppress tumor cell proliferation without substantially interfering with normal cell growth, thus holding promise for cancer treatment. A structure-based approach to the design of improved FT inhibitors relies on knowledge of the conformational flexibility of the zinc-containing active site of FT. Although several X-ray structures of FT have been reported, detailed information regarding the active site conformational flexibility of the enzyme is still not available. Molecular dynamics (MD) simulations of FT can offer the requisite information, but have not been applied due to a lack of effective methods for simulating the four-ligand coordination of zinc in proteins. Here, we report in detail the problems that occurred in the conventional MD simulations of the zinc-bound FT and a solution to these problems by employing a simple method that uses cationic dummy atoms to impose orientational requirement for zinc ligands. A successful 1.0 ns (1.0 fs time step) MD simulation of zinc-bound FT suggests that nine conserved residues (Asn127±, Gln162±, Asn165±, Gln195±, His248², Lys294², Leu295², Lys353², and Ser357²) in the active site of mammalian FT are relatively mobile. Some of these residues might be involved in the ligand-induced active site conformational rearrangement upon binding and deserve attention in screening and design of improved FT inhibitors for cancer chemotherapy. [ABSTRACT FROM PUBLISHER]

Optical neural networks (ONNs) have shown great promise in overcoming the speed and efficiency bottlenecks of artificial neural networks. However, the absence of high‐speed, energy‐efficient nonlinear activators significantly impedes the advancement of ONNs and their extension to ultrafast application scenarios like real‐time intelligent signal processing. In this work, a novel silicon/graphene ultrafast all‐optical nonlinear activator, leveraging the hybrid integration of silicon slot waveguides, plasmonic slot waveguides, and monolayer graphene is demonstrated. Exploiting the exceptional picosecond‐scale photogenerated carrier relaxation time of graphene, the response time of the activator is markedly reduced to ≈93.6 ps, establishing all‐optical activator as the fastest known in silicon photonics to knowledge. Moreover, the all‐optical nonlinear activator holds a low threshold power of 5.49 mW and a corresponding power consumption per activation of 0.51 pJ. Its feasibility and capability for use in ONNs, manifesting performance comparable with commonly used activation functions are experimentally confirmed. This breakthrough in speed and energy efficiency of all‐optical nonlinear activators opens the door to significant improvements in the performance and applicability of ONNs. [ABSTRACT FROM AUTHOR]

In this letter, a microstrip dual-band bandpass filter (BPF) using novel side-stub-loaded resonator has been presented.By loading two open stubs at the symmetrical sides of a uniform-impedance resonator, the center frequency of the fundamental odd mode could be independently controlled while that of the fundamental even mode is fixed. A dual-band filter using pseudo-interdigital configuration is implemented with three transmission zeros. To validate the design and analysis, a dual-band BPF has been designed and fabricated with its two bands located at 2.4/5.2 GHz. It is shown that the measured and simulated performances are in good agreement. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:362-364 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26537 [ABSTRACT FROM AUTHOR]

A distributed fiber optic intrusion detection sensor is proposed, in which a nonbalanced Mach-Zehnder interferometer is used as phase demodulator, and an optical time domain reflectometer is used as a position detector. The experimental results concluded that the positioning error of ±25m can be achieved along an 8.8-km single mode fiber. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2746-2748, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25602 [ABSTRACT FROM AUTHOR]

State of charge (SOC) estimation plays a critical role in the operation of an electric vehicle (EV) power battery. In this Letter, the authors propose machine learning (ML) algorithms as alternate to the existing filtering algorithms used for SOC estimation of an EV battery. The SOC estimation approach is evaluated by the simulation experiments in advanced vehicle simulator (ADVISOR). For the modelling of ML algorithms, the input parameters that affect the SOC estimation are battery current, battery module temperature, power out of the battery (available and requested), battery power loss and heat removed from the battery. Training and testing stages of the models are carried out using the data collected from ADVISOR. As the drive cycle conditions provided by ADVISOR are universal therefore present method is applicable to all kinds of batteries used in EVs including lithium ion, nickel metal hydride and lead acid batteries. Thus, the proposed models for SOC estimation provide an alternative approach in SOC estimation. [ABSTRACT FROM AUTHOR]

Although planar‐structured perovskite solar cells (PSCs) have power conversion efficiencies exceeding 24%, the poor photostability, especially with ultraviolet irradiance (UV) severely limits commercial application. The most commonly‐used TiO2 electron selective layer has a strong photocatalytic effect on perovskite/TiO2 interface when TiO2 is excited by UV light. Here a UV‐inert ZnTiO3 is reported as the electron selective layer in planar PSCs. ZnTiO3 is a perovskite‐structured semiconductor with excellent chemical stability and poor photocatalysis. Solar cells are fabricated with a structure of indium doped tin oxide (ITO)/ZnTiO3/Cs0.05FA0.81MA0.14PbI2.55Br0.45/Sprio‐MeOTAD/Au. The champion device exhibits a stabilized power conversion efficiency of 19.8% with improved photostability. The device holds 90% of its initial efficiency after 100 h of UV soaking (365 nm, 8 mW cm−2), compared with 55% for TiO2‐based devices. This work provides a new class of electron selective materials with excellent UV stability in perovskite solar cell applications. [ABSTRACT FROM AUTHOR]

A novel approach to promote hydrophobic association by incorporating short alkyl chains onto polyelectrolytes (HAPEs) was presented. A series of HAPEs was synthesized by free radical copolymerization in aqueous media with acrylamide (AM), 11‐acrylamidoundecanoic acid (C11AM), and 6‐acrylamidohexanoic acid (C6AM). The structures and compositions of the polymers were confirmed by 1H‐NMR, and the molecular weights were determined by GPC. Results of rheological experiments revealed that viscosities increased greatly in samples containing C11AM and C6AM compared with the sample without C6AM. The sample without C6AM was also characterized by critical association concentrations and critical angular frequencies. Solubilization and bridging interaction were considered as the possible reasons. Pyrene fluorescence probe data and 1H‐NMR spin–spin relaxation times further illustrated the reinforcement of hydrophobic associations by short alkyl side chains. All the results showed that the optimum content of C6AM was 1 mol % in the prepared HAPEs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47581. [ABSTRACT FROM AUTHOR]

In article number 1808376, Cheng Song, Feng Pan, and co‐workers report a high‐performance two‐terminal selector based on a symmetrical multilayer structure of homogeneous tantalum oxides, possessing bidirectional threshold switching operation, large selectivity, high compliance currents, and tunable threshold voltages. The selector can realize 1S1R read‐write functions, thus avoiding crosstalk issues, and is stacked with a memristor. The design might advance practical implementation of two‐terminal selectors in the field of emerging memories and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Two‐terminal selectors with high nonlinearity, based on bidirectional threshold switching (TS) behaviors, are considered as a crucial element of crossbar integration for emerging nonvolatile memory and neuromorphic network. Although great efforts have been made to obtain various selectors, existing selectors cannot fully satisfy the rigorous standard of assorted memristive elements and it is in great demand to enhance the performance. Here, a new type of Ag/TaOx/TaOy/TaOx/Ag (x < y) selector based on homogeneous trilayered oxides is developed to attain the required parameters including bidirectional TS operation, a large selectivity of ≈1010, a high compliance current up to 1 mA, and ultralow switching voltages under 0.2 V. Tunable operation voltages can be realized by modulating the thickness of inserted TaOy. All‐TaOx‐based integrated 1S1R (one selector and one memristor) cells, prepared completely by magnetron sputtering and no need of a middle electrode, exhibit a nonlinear feature, which is quite characteristic for the crossbar devices, avoiding undesired crosstalk current issues. The tantalum‐oxide‐based homojunctions offer high insulation, low ion mobility, and rich interfaces, which is responsible for the modulation of Ag conductive filaments and corresponding high‐performance cation‐based selector. These findings might advance practical implementation of two‐terminal selectors in emerging memories, especially resistive random access memories. A high‐performance two‐terminal selector based on a symmetrical multilayer design is developed, possessing bidirectional threshold switching operations, a large selectivity of ≈1010, a high compliance current up to 1 mA, and tunable threshold voltages. Stacked with a memristor, the selector can realize 1S1R (one‐selector‐one‐memristor) function, avoiding crosstalk issues. A reasonable hourglass model is proposed to interpret the underlying mechanism. [ABSTRACT FROM AUTHOR]

The front cover picture, provided by Ke‐Jing Li, Kun Xu, Yong‐Guo Liu, Cheng‐Chu Zeng, and Bao‐Guo Sun, illustrates an efficient protocol for the synthesis of 3‐aminoquinoxalinones via the electrochemical dehydrogenative C‐3 amination of quinoxalin‐2(1H)‐ones in a simple undivided cell under constant current electrolysis conditions. With aliphatic amines and azoles as the nitrogen sources, a series of 3‐aminoquinoxalinones could be obtained in up to 99% yield. This direct electrolytic method avoids the use of transition metals and external oxidants, and it represents an appealing alternative to the synthesis of 3‐aminoquinoxalinone. Details of this work can be found in the full paper on pages 1033–1041 (K.‐J. Li, K. Xu, Y.‐G. Liu, C.‐C. Zeng, B.‐G. Sun, Adv. Synth. Catal. 2019, 361, 1033–1041; DOI: 10.1002/adsc.201800989). [ABSTRACT FROM AUTHOR]

Broadband photodetection is central to spectroscopy, imaging, and sensing in modern science and technology. However, traditional devices suffer from a higher dark current because as‐adopted photoactive semiconductors tend to be accompanied by a large noise output due to higher conductivity, resulting in low sensitivity and detectivity. The utilization of photon manipulation as enhancing light–matter interaction on a deep subwavelength scale provides a fascinating opportunity to achieve higher photocurrent while keeping a low noise level. Here, an ultrasensitive flexible broadband photodetector based on multiphysics coupled nanogold–perovskite films is demonstrated. The mechanism involves optimized interfacial injection, bulk transport, photon trapping, and energy transformation, and leads to high photosensitivity (≈105), low detection limit (5.7 pW), and wide spectral response (UV–vis–NIR). These results show that the nanometal–perovskite framework can be used as a powerful platform for ultrasensitive flexible broadband photodetection, competitive with state‐of‐the‐art commercial devices or publications. The multiphysics coupled nanogold–perovskite films in the designed metal–semiconductor–metal architecture significantly enhance light‐harvesting and hot‐electron exploitation, leading to achieving an ultrasensitive flexible broadband photodetector with pW scale detection limit and UV–vis–NIR spectral response. [ABSTRACT FROM AUTHOR]

The front cover picture, provided by Sen Liang, Kun Xu, Cheng‐Chu Zeng, Hong‐Yu Tian, Bao‐Guo Sun, exhibits the advances in using electrochemistry for α‐C−H oxidative functionalization of carbonyl compounds. α‐C−H bond functionalization of carbonyl compounds to afford more versatile functionalized groups has become a promising strategy for atom‐economical C−C and C−X bond formation. Organic electrosynthesis is revolutionizing the way of organic synthesis, and this field has seen explosive growth in recent years. Details can be found in the review on pages 4266–4292 (S. Liang, K. Xu, C.‐C. Zeng, H.‐Y. Tian, B.‐G. Sun, Adv. Synth. Catal. 2018, 360, 4266–4292; DOI: 10.1002/adsc.201800519). [ABSTRACT FROM AUTHOR]

Mitochondrial base editing with DddA‐derived cytosine base editor (DdCBE) is limited in the accessible target sequences and modest activity. Here, the optimized DdCBE tools is presented with improved editing activity and expanded C‐to‐T targeting scope by fusing DddA11 variant with different cytosine deaminases with single‐strand DNA activity. Compared to previous DdCBE based on DddA11 variant alone, fusion of the activation‐induced cytidine deaminase (AID) from Xenopus laevis not only permits cytosine editing of 5′‐GC‐3′ sequence, but also elevates editing efficiency at 5′‐TC‐3′, 5′‐CC‐3′, and 5′‐GC‐3′ targets by up to 25‐, 10‐, and 6‐fold, respectively. Furthermore, the A‐to‐G editing efficiency is significantly improved by fusing the evolved DddA6 variant with TALE‐linked deoxyadenosine deaminase (TALED). Notably, the authors introduce the reported high‐fidelity mutations in DddA and add nuclear export signal (NES) sequences in DdCBE and TALED to reduce off‐target editing in the nuclear and mitochondrial genome while improving on‐target editing efficiency in mitochondrial DNA (mtDNA). Finally, these engineered mitochondrial base editors are shown to be efficient in installing mtDNA mutations in human cells or mouse embryos for disease modeling. Collectively, the study shows broad implications for the basic study and therapeutic applications of optimized DdCBE and TALED. [ABSTRACT FROM AUTHOR]

Three‐element in‐phase coherently coupled arrays of vertical cavity surface‐emitting lasers (VCSELs) were fabricated using proton implantation. The arrays show excellent beam quality with a far‐field divergence of 4°, while maintaining a stable in‐phase mode until a maximum output power of 4 mW under continuous‐wave condition. The process for the arrays is simple and the cost is low. [ABSTRACT FROM AUTHOR]