bluuebunny/crossref_metadata_2025 huggingface dataset:
Bright Aggregation‐Induced‐Emission Dots for Targeted Synergetic NIR‐II Fluorescence and NIR‐I Photoacoustic Imaging of Orthotopic Brain Tumors
Authors: Sheng Zonghai , Guo Bing , Hu Dehong , Xu Shidang , Wu Wenbo , Liew Weng Heng , Yao Kui , Jiang Jingying , Liu Chengbo , Zheng Hairong , Liu Bin
Published: May 2018

Precise diagnostics are of significant importance to the optimal treatment outcomes of patients bearing brain tumors. NIR‐II fluorescence imaging holds great promise for brain‐tumor diagnostics with deep penetration and high sensitivity. This requires the development of organic NIR‐II fluorescent agents with high quantum yield (QY), which is difficult to achieve. Herein, the design and synthesis of a new NIR‐II fluorescent molecule with aggregation‐induced‐emission (AIE) characteristics is reported for orthotopic brain‐tumor imaging. Encapsulation of the molecule in a polymer matrix yields AIE dots showing a very high QY of 6.2% with a large absorptivity of 10.2 L g−1 cm−1 at 740 nm and an emission maximum near 1000 nm. Further decoration of the AIE dots with c‐RGD yields targeted AIE dots, which afford specific and selective tumor uptake, with a high signal/background ratio of 4.4 and resolution up to 38 µm. The large NIR absorptivity of the AIE dots facilitates NIR‐I photoacoustic imaging with intrinsically deeper penetration than NIR‐II fluorescence imaging and, more importantly, precise tumor‐depth detection through intact scalp and skull. This research demonstrates the promise of NIR‐II AIE molecules and their dots in dual NIR‐II fluorescence and NIR‐I photoacoustic imaging for precise brain cancer diagnostics.
A Scalable Approach to Dendrite‐Free Lithium Anodes via Spontaneous Reduction of Spray‐Coated Graphene Oxide Layers
Authors: Bai Maohui , Xie Keyu , Yuan Kai , Zhang Kun , Li Nan , Shen Chao , Lai Yanqing , Vajtai Robert , Ajayan Pulickel , Wei Bingqing
Published: May 2018

Li‐metal batteries (LiMBs) are experiencing a renaissance; however, achieving scalable production of dendrite‐free Li anodes for practical application is still a formidable challenge. Herein, a facile and universal method is developed to directly reduce graphene oxide (GO) using alkali metals (e.g., Li, Na, and K) in moderate conditions. Based on this innovation, a spontaneously reduced graphene coating can be designed and modulated on a Li surface (SR‐G‐Li). The symmetrical SR‐G‐Li|SR‐G‐Li cell can run up to 1000 cycles at a high practical current density of 5 mA cm−2 without a short circuit, demonstrating one of the longest lifespans reported with LiPF6‐based carbonate electrolytes. More significantly, a practically scalable paradigm is established to fabricate dendrite‐free Li anodes by spraying a GO layer on the Li anode surface for large‐scale production of LiFePO4/Li pouch cells, reflected by the continuous manufacturing of the SR‐G‐Li anodes based on the roll‐to‐roll technology. The strategy provides new commercial opportunities to both LiMBs and graphene.
Self‐Powered n‐SnO2/p‐CuZnS Core–Shell Microwire UV Photodetector with Optimized Performance
Authors: Cai Jian , Xu Xiaojie , Su Longxing , Yang Wei , Chen Hongyu , Zhang Yong , Fang Xiaosheng
Published: May 2018

Herein, a single‐crystal SnO2 microwire photodetector (PD) is demonstrated with a fast response speed owing to a low concentration of point defects. However, the presence of surface defects (e.g., oxygen vacancies) still limits its optoelectronic performance. To further improve the photoresponse of such device, a core–shell p–n junction is constructed by simply coating a new p‐type transparent conductive (CuS)0.35:(ZnS)0.65 nanocomposite film (CuZnS) on n‐type SnO2 microwire. As a result, not only the surface of SnO2 is modified, but also a space charge depletion region is formed at the interface, leading to an enhanced on‐off ratio of ≈1.3 × 103 and a faster speed of 45 µs/1.17 ms (rise time/decay time) in comparison with the plain SnO2 microwire PD (on‐off ratio of 30, response speed of ≈100 µs/1.5 ms). Besides, the n‐SnO2/p‐CuZnS core–shell microwire could steadily work as a self‐powered UV PD, with a maximum responsivity of 1.6 mA W−1 (at 0 V) and detectivity of 5.41 × 1011 Jones (at 0.05 V) toward 315 nm, which suggests its great potentials as a high‐performance self‐powered UV photodetector.
Investigation on Charge Carrier Recombination of Hybrid Organic–Inorganic Perovskites Doped with Aggregation‐Induced Emission Luminogen under High Photon Flux Excitation
Authors: Chen Zhifan , Chen Zeqiang , Li Hao , Zhao Xiaojuan , Zhu Mingqiang , Wang Mingkui
Published: May 2018

A typical aggregation‐induced emission luminogen (AIE‐gen) is introduced into perovskite CH3NH3PbI3 and the material and photophysical properties of hybrid films are investigated with absorption, X‐ray diffraction, and steady‐state photoluminescence (PL) characterization. When excited by a high photon flux (4.08 × 1022 cm−2 s−1) laser beam (3.82 eV) at room temperature, the CH3NH3PbI3 polycrystalline thin films exhibit dual emission locating at 1.64 eV (P1) and 1.59 eV (P2). The two PL peaks are attributed to free carrier (FC) recombination and exciton recombination, respectively. Additionally, an introduction of AIE‐gen changes the peak value ratio of P1:P2, indicating the radiative recombination ratio of FCs versus excitons in perovskite films can be tuned with this method. Since recombination of FCs and excitons plays a key role in photovoltaic and luminescent devices, this finding helps to clarify the recombination behavior of photogenerated carriers in perovskites and promote their further applications in photoelectric devices.
Rhodium‐Catalyzed Tandem Reaction of Isocyanides with Trifluorodiazoethane and Nucleophiles: Divergent Synthesis of Trifluoroethyl‐Substituted Isoquinolines, Imidates, and Amidines
Authors: Bu Xiu‐Bin , Wang Zhuo , Wang Xue‐Di , Meng Xiang‐He , Zhao Yu‐Long
Published: May 2018

A rhodium‐catalyzed tandem reaction of isocyanides with 2,2,2‐trifluorodiazoethane and various nucleophiles has been developed. The protocol provides a simple and highly efficient method for the construction of trifluoroethyl‐substituted isoquinolines, imidates and amidines with broad substrate scope in good to high yields. These reactions feature readily available starting materials, three‐component, one‐pot procedure, good to high yields, broad substrate scope, good functional group tolerance, and excellent stereoselectivity.

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Oxidative [3+3] Annulation of Atropaldehyde Acetals with 1,3‐Bisnucleophiles: An Efficient Method of Constructing Six‐Membered Aromatic Rings, Including Salicylates and Carbazoles
Authors: Gu Yanlong , Wu Fengtian , Yang Jian
Published: May 2018

An oxidative [3+3] annulation of atropaldehyde acetals with various 1,3‐bisnucleophiles was developed using either N‐bromosuccinimide or copper(II) bromide as oxidizing reagent and Brønsted or Lewis acids as catalyst. The [3+3] annulations can be considered mechanistically as oxidizing reagent‐induced acid‐acid‐catalyzed domino reactions established through the concept of auto‐tandem catalysis. Alkyl acetoacetates, α‐(indol‐2‐yl)acetate, anilines, 1‐methyl‐1H‐pyrazol‐3‐amine, ethyl 5‐amino‐1H‐pyrazole‐3‐carboxylate, and 3‐amino‐1H‐indazole can all be used as 1,3‐bisnucleophiles in this type of transformation. The established reactions can very efficiently construct six‐membered aromatic rings, including salicylates and carbazoles. A four‐step method of synthesizing the anti‐inflammatory agent diflunisal was also developed based on the oxidative [3+3] annulation reaction, and the yield was high.

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Decellularized Extracellular Matrix Hydrogels as a Delivery Platform for MicroRNA and Extracellular Vesicle Therapeutics
Authors: Hernandez Melissa J. , Gaetani Roberto , Pieters Vera M. , Ng Nathan W. , Chang Audrey E. , Martin Taylor R. , van Ingen Eva , Mol Emma A. , Dzieciatkowska Monika , Hansen Kirk C. , Sluijter Joost P.G. , Christman Karen L.
Published: May 2018

In the last decade, the use of microRNA (miRNA) and extracellular vesicle (EV) therapies has emerged as an alternative approach to mitigate the negative effects of several disease pathologies ranging from cancer to tissue and organ regeneration; however, delivery approaches toward target tissues have not been optimized. To alleviate these challenges, including rapid diffusion upon injection and susceptibility to degradation, porcine‐derived decellularized extracellular matrix (ECM) hydrogels are examined as a potential delivery platform for miRNA and EV therapeutics. The incorporation of EVs and miRNA antagonists, including anti‐miRs and antago‐miRs, in ECM hydrogels results in a prolonged release as compared to the biologic agents alone. In addition, individual in vitro assessments confirm the bioactivity of the therapeutics upon release from the ECM hydrogels. This work demonstrates the feasibility of encapsulating miRNA and EV therapeutics in ECM hydrogels to enhance delivery and potentially efficacy in later in vivo applications.
Why Can High Charge‐Carrier Mobilities be Achieved Along π‐Conjugated Polymer Chains with Alternating Donor–Acceptor Moieties?
Authors: Brédas Jean‐Luc , Li Yuan , Sun Haitao , Zhong Cheng
Published: May 2018

Impressive charge‐carrier mobilities have been measured over the past few years for a number of well‐oriented π‐conjugated polymer chains. Intriguingly, these polymers frequently have complex chemical structures consisting of repeat units with alternating electron‐rich and electron‐poor moieties. A priori, such structures do not lend themselves to the presence of strongly dispersive valence or conduction electronic bands, which are required to achieve small charge‐carrier effective masses. Here, the factors that can lead to high carrier mobilities in the tens or even hundreds of square centimeter per volt per second are described briefly.
A Tumor Vascular‐Targeted Interlocking Trimodal Nanosystem That Induces and Exploits Hypoxia
Authors: Luan Xin , Guan Ying‐Yun , Liu Hai‐Jun , Lu Qin , Zhao Mei , Sun Duxin , Lovell Jonathan F. , Sun Peng , Chen Hong‐Zhuan , Fang Chao
Published: May 2018

Vascular‐targeted photodynamic therapy (VTP) is a recently approved strategy for treating solid tumors. However, the exacerbated hypoxic stress makes tumor eradication challenging with such a single modality approach. Here, a new graphene oxide (GO)‐based nanosystem for rationally designed, interlocking trimodal cancer therapy that enables VTP using photosensitizer verteporfin (VP) (1) with codelivery of banoxantrone dihydrochloride (AQ4N) (2), a hypoxia‐activated prodrug (HAP), and HIF‐1α siRNA (siHIF‐1α) (3) is reported. The VTP‐induced aggravated hypoxia is highly favorable for AQ4N activation into AQ4 (a topoisomerase II inhibitor) for chemotherapy. However, the hypoxia‐induced HIF‐1α acts as a “hidden brake,” through downregulating CYP450 (the dominant HAP‐activating reductases), to substantially hinder AQ4N activation. siHIF‐1α is rationally adopted to suppress the HIF‐1α expression upon hypoxia and further enhance AQ4N activation. This trimodal nanosystem significantly delays the growth of PC‐3 tumors in vivo compared to the control nanoparticles carrying VP, AQ4N, or siHIF‐1α alone or their pairwise combinations. This multimodal nanoparticle design presents, the first example exploiting VTP to actively induce hypoxia for enhanced HAP activation. It is also revealed that HAP activation is still insufficient under hypoxia due to the hidden downregulation of the HAP‐activating reductases (CYP450), and this can be well overcome by GO nanoparticle‐mediated siHIF‐1α intervention.
A Sandwich‐Like Organolead Halide Perovskite Photocathode for Efficient and Durable Photoelectrochemical Hydrogen Evolution in Water
Authors: Zhang Hefeng , Yang Zhou , Yu Wei , Wang Hong , Ma Weiguang , Zong Xu , Li Can
Published: May 2018

Organolead halide perovskite materials have demonstrated great potential in the solar cells field owing to their excellent optoelectronic properties. However, the instability issue of the perovskites impedes the translation of their attractive features for the solar fuel production such as photoelectrochemical H2 production from water splitting. Herein, CH3NH3PbI3 a photocathode with a sandwich‐like structure is fabricated with a general and scalable approach toward addressing this issue. The photocathode exhibits an onset potential at 0.95 V versus reversible hydrogen electrode (RHE) and a photocurrent density of −18 mA cm−2 at 0 V versus RHE with an impressive ideal ratiometric power‐saved efficiency of 7.63%. More impressively, the photocathode retains good stability under 12 h continuous illumination in water at wide pH range. This performance is much superior to that of the best perovskite‐based photoelectrode ever reported.
Light‐Gated Rotation in a Molecular Motor Functionalized with a Dithienylethene Switch
Authors: Roke Diederik , Stuckhardt Constantin , Danowski Wojciech , Wezenberg Sander J. , Feringa Ben L.
Published: May 2018

A multiphotochromic hybrid system is presented in which a light‐driven overcrowded alkene‐based molecular rotary motor is connected to a dithienylethene photoswitch. Ring closing of the dithienylethene moiety, using an irradiation wavelength different from the wavelength applied to operate the molecular motor, results in inhibition of the rotary motion as is demonstrated by detailed 1H‐NMR and UV/Vis experiments. For the first time, a light‐gated molecular motor is thus obtained. Furthermore, the excitation wavelength of the molecular motor is red‐shifted from the UV into the visible‐light region upon attachment of the dithienylethene switch.
{Nb288O768(OH)48(CO3)12}: A Macromolecular Polyoxometalate with Close to 300 Niobium Atoms
Authors: Wu Yan‐Lan , Li Xin‐Xiong , Qi Yan‐Jie , Yu Hao , Jin Lu , Zheng Shou‐Tian
Published: May 2018

A protein‐sized (ca. 4.2×4.2×3.6 nm3) non‐biologically derived molecule {Nb288O768(OH)48(CO3)12} (Nb288) containing up to 288 niobium atoms has been obtained, which is by far the largest and the highest nuclearity polyoxoniobate (PONb). Particularly, in terms of metal nuclearity number, Nb288 is the second largest cluster so far reported in classic polyoxometalate chemistry (V, Mo, W, Nb, and Ta). Nb288 can be described as a giant windmill‐like cluster aggregate of six nanoscale high‐nuclearity PONb units {Nb47O128(OH)6(CO3)2} (Nb47) joined together by six additional Nb ions. Interestingly, the 47‐nuclearity Nb47 units generated in situ can be isolated and bridged by copper complexes to form an inorganic–organic hybrid three‐dimensional PONb framework, which exhibits effective catalytic activity for hydrolyzing nerve agent simulant of dimethyl methylphosphonate. The unique Nb47 cluster also provides a new type of topology to very limited family of Nb‐O clusters.
Remote Control of Anion–π Catalysis on Fullerene‐Centered Catalytic Triads
Authors: López‐Andarias Javier , Bauzá Antonio , Sakai Naomi , Frontera Antonio , Matile Stefan
Published: May 2018

The design, synthesis and evaluation of catalytic triads composed of a central C60 fullerene with an amine base on one side and polarizability enhancers on the other side are reported. According to an enolate addition benchmark reaction, fullerene–fullerene–amine triads display the highest selectivity in anion–π catalysis observed so far, whereas NDI–fullerene–amine triads are not much better than fullerene–amine controls (NDI=naphthalenediimide). These large differences in activity are in conflict with the small differences in intrinsic π acidity, that is, LUMO energy levels and π holes on the central fullerene. However, they are in agreement with the high polarizability of fullerene–fullerene–amine triads. Activation and deactivation of the fullerene‐centered triads by intercalators and computational data on anion binding further indicate that for functional relevance, intrinsic π acidity is less important than induced π acidity, that is, the size of the oriented macrodipole of polarizable π systems that emerges only in response to the interaction with anions and anionic transition states. The resulting transformation is thus self‐induced, the anionic intermediates and transition states create their own anion–π catalyst.
High Rate of Drug‐Free Remission After Induction Therapy With Golimumab in Early Peripheral Spondyloarthritis
Authors: Carron Philippe , Varkas Gaëlle , Renson Thomas , Colman Roos , Elewaut Dirk , Van den Bosch Filip
Published: May 2018

Objective

New treatment algorithms using tumor necrosis factor (TNF) blockers in early stages of spondyloarthritis (SpA) induce high rates of clinical remission or low disease activity. It could be anticipated that such early intervention strategies in peripheral SpA may induce drug‐free remission. We undertook this study to evaluate drug‐free clinical remission after induction therapy with golimumab in patients with very early active peripheral SpA, and to identify patient characteristics that predict sustained drug‐free remission.

Methods

Eligible patients were age ≥18 years and fulfilled the Assessment of SpondyloArthritis international Society criteria for peripheral SpA. All patients had symptom duration of <12 weeks. Sustained clinical remission was defined as the absence of arthritis, enthesitis, and dactylitis at 2 consecutive major visits, after which treatment was withdrawn. Patients were prospectively followed up to assess the rate of sustained drug‐free clinical remission and clinical relapse.

Results

Eighty‐two percent of patients (49 of 60) fulfilled sustained clinical remission criteria after a regimen of induction therapy with golimumab. The majority of patients already reached this status at week 24 (n = 30), with an additional 11 and 8 patients at weeks 36 and 48, respectively. All patients had a follow‐up period of at least 18 months after drug withdrawal. Fifty‐three percent of patients (26 of 49) still have drug‐free remission of their disease. Inability to sustain drug‐free remission was associated with the presence of psoriasis and polyarticular disease (swollen joint count >5).

Conclusion

Anti‐TNF treatment in very early peripheral SpA results in a remarkably high rate of sustained clinical remission. More than 50% of patients continue to have remission of their disease after withdrawal of therapy, which highlights a defined window of opportunity permitting induction of drug‐free remission.
Association of Abnormal Elevations in IFIT3 With Overactive Cyclic GMP‐AMP Synthase/Stimulator of Interferon Genes Signaling in Human Systemic Lupus Erythematosus Monocytes
Authors: Wang Jiehua , Dai Min , Cui Yange , Hou Guojun , Deng Jun , Gao Xin , Liao Zhuojun , Liu Ya , Meng Yao , Wu Lingling , Yao Chao , Wang Yan , Qian Jie , Guo Qiang , Ding Huihua , Qu Bo , Shen Nan
Published: May 2018

Objective

Increasing evidence indicates that the cyclic GMP‐AMP synthase/stimulator of interferon genes (cGAS/STING) signaling pathway has a critical pathogenic role in systemic lupus erythematosus (SLE). Expression levels of the interferon (IFN)–inducible gene IFIT3 are elevated in SLE patients. However, it is still not clear how IFIT3 contributes to the pathogenesis of SLE. This study was undertaken to investigate the activation of the cGAS/STING signaling pathway in human SLE monocytes, and to determine how elevated expression of IFIT3 could contribute to overactive cGAS/STING signaling in patients with SLE.

Methods

Monocytes from SLE patients or healthy controls were examined for activity of the cGAS/STING signaling pathway and expression levels of IFIT3. Correlations between cGAS/STING signaling activity and SLE clinical features were analyzed. Gain‐ or loss‐of‐function experiments were used to determine the role of IFIT3 in cGAS/STING signaling. Coimmunoprecipitation assays were used to identify the interaction between IFIT3 and other proteins.

Results

The cGAS/STING signaling pathway was found to have enhanced activity in monocytes from SLE patients compared to healthy controls, as indicated by the higher expression of IFNβ downstream. Levels of IFIT3 were significantly elevated in human SLE monocytes, and this was positively correlated with the activity of the cGAS/STING signaling pathway. In vitro, the expression of VACV70‐induced IFNβ was reduced by knockdown of IFIT3, whereas overexpression of IFIT3 produced an opposite effect. Finally, IFIT3 was found to interact with both STING and TANK‐binding kinase 1.

Conclusion

These findings suggest that IFIT3 is one of the genes that contributes to the overactive cGAS/STING signaling pathway in human SLE monocytes. IFIT3 may therefore serve as a novel therapeutic target for blocking the production of type I IFN and other proinflammatory cytokines by the cGAS/STING signaling pathway in patients with SLE.
Microbial biosynthesis and in vivo depolymerization of intracellular medium‐chain‐length poly‐3‐hydroxyalkanoates as potential route to platform chemicals
Authors: Anis Siti Nor Syairah , Mohd Annuar Mohd Suffian , Simarani Khanom
Published: May 2018

Biosynthesis and in vivo depolymerization of intracellular medium‐chain‐length poly‐3‐hydroxyalkanoates (mcl‐PHA) in Pseudomonas putida Bet001 grown on lauric acid were studied. Highest mcl‐PHA fraction (>50 % of total biomass) and cell concentration (8 g L−1) were obtained at carbon‐to‐nitrogen (C/N) ratio 20, starting cell concentration 1 g L−1, and 48 H fermentation. The mcl‐PHA comprised of 3‐hydroxyhexanoate (C6), 3‐hydroxyoctanote (C8), 3‐hydroxydecanoate (C10), and 3‐hydroxydodecanoate (C12) monomers. In vivo action was studied in a mineral liquid medium without carbon source, and in different buffer solutions with varied pH, molarity, ionic strength, and temperature. The monomer liberation rate reflected the mol percentage distribution of the initial polymer subunit composition. Rate and percentage of in vivo depolymerization were highest in 0.2 M Tris–HCl buffer (pH 9, strength = 0.2 M, 30 °C) at 0.21 g L−1 H−1 and 98.6 ± 1.3 wt%, respectively. There is a congruity vis‐à‐vis to specific buffer type, molarity, pH, ionic strength, and temperature values for superior in vivo depolymerization activities. Direct products from in vivo depolymerization matched the individual monomeric composition of native mcl‐PHA. It points to exo‐type reaction for the in vivo process, and potential biological route to chiral molecules.
Bioenergy from Microalgae – Vision or Reality?
Authors: Hoyer Jan , Cotta Fritz , Diete Anja , Großmann Jochen
Published: May 2018

Microalgae are often heralded as a miracle cure to solve future questions concerning energy and food supply of the world's population. This is due to their vastly superior area productivity compared to terrestrial plants and the feasibility of cultivating them independently of arable land and fresh water. Algal biomass can be used as food and feed as well as a source for a plethora of biofuels and high value products such as nutraceuticals and pharmaceuticals. This review article seeks to shed light on recent advances in microalgal technology and their potential for the production of biofuels.
A Glutathione‐Responsive Short Sequence of Metal–Organic Complex Array
Authors: Bose Purnandhu , Takei Toshiaki , Li Xianglan , Minowa Takashi , Rajmohan Rajamani , Vairaprakash Pothiappan , Tashiro Kentaro
Published: May 2018

A short metal–organic complex array (MOCA) containing a sequence of RPtRRu (1Cl) was found to exhibit unique responses to a major biothiol, glutathione (GSH). Upon binding of GSH to 1Cl, the resultant 1:1 complex (1GS) formed nanofibrous assemblies that suggested supramolecular polymerization through the double‐salt‐bridge structure formation. The binding behavior of this MOCA sequence to calf thymus DNA was also dependent on GSH; a larger conformational change of DNA was observed upon binding with 1GS, relative to that with 1Cl.
A Sustainable Method for the Synthesis of Acetic Acid Based on Dehydrogenation of an Ethanol–Water Solution Catalyzed by an Iridium Complex Bearing a Functional Bipyridonate Ligand
Authors: Kuwahara Masato , Nishioka Masaaki , Yoshida Masato , Fujita Ken‐ichi
Published: May 2018

An efficient system for the synthesis of acetic acid via dehydrogenation of an ethanol–water solution using a new iridium catalyst bearing a functional bipyridonate ligand with N,N‐dimethylamino substituents was developed. Quantitative production of acetic acid from an ethanol–water solution was achieved. In addition, recovery and reuse of the catalyst using a simple procedure was also accomplished. Moreover, this catalytic system can be applied in the dehydrogenative transformation of various primary alcohols to the corresponding carboxylic acids.
Facile Synthesis of Nitrogen‐Doped Mesoporous Hollow Carbon Nanospheres for High‐Performance Supercapacitors
Authors: Wang Zhongbing , Qiang Hongwen , Zhu Zihao , Liu Jinpeng , Chen Chunnian , Zhang Dawei
Published: May 2018

We report the facile preparation of nitrogen‐doped mesoporous hollow carbon nanospheres (N‐MHCNS) by directly carbonizing hollow polypyrrole nanospheres that are derived from in situ polymerization. Here, we use a novel soft template (PMMA‐PBMA‐PMAA) as the core. At 700 °C, the obtained N‐MHCNSs (denoted N‐MHCNS700) show superior electrochemical performance. In 1 M HCl electrolyte, N‐MHCNS700 exhibits a capacitance as high as 275.5 F g−1 at a current density of 1 A g−1 and a high rate capability, retaining 54.4 % of the initial capacitance at the current density of 20 A g−1. In addition, the specific capacitance of N‐MHCNS700 is approximately 100 % retained at a current density of 10 A g−1 after 5000 cycles, indicating amazing stable cycling performance. The excellent electrochemical performance can be derived from the amorphous graphitic carbon, hollow nanosphere structure, mesoporous properties, and nitrogen doping effect.
Facile Skeletal Rearrangement of Polycyclic Disilenes with Bicyclo[1.1.1]pentasilanyl Groups
Authors: Yokouchi Yuki , Ishida Shintaro , Iwamoto Takeaki
Published: May 2018

The unexpected formations of fused polycyclic disilenes 2 a and (E),(Z)‐3 b by the reduction of the 1,2‐dibromodisilanes 5 a (R=Me) and 5 b (R=iPr) bearing bicyclo[1.1.1]pentasilanyl (BPS) groups is reported. The disilenes 2 a and (E),(Z)‐3 b were characterized by a combination of NMR spectroscopy and X‐ray diffraction analysis (XRD). The reduction of 5 b in the presence of 2,3‐dimethyl‐1,3‐butadiene provided an ene adduct of the disilene 1 b bearing BPS groups, which suggested that an initial product of the reduction of 5 b was the disilene 1 b. Thermal reactions of 2 a and (E),(Z)‐3 b afforded the highly strained saturated silicon clusters 4 a and 4 b. A computational study suggested that the transformation of 1 to 2, 3, or 4 can involve silyldisilene–disilanylsilylene rearrangement reactions and insertion reactions of a silylene into a Si−Si bond.
One‐Pot Synthesis of CuS Nanoflower‐Decorated Active Carbon Layer for High‐Performance Asymmetric Supercapacitors
Authors: Wang Guoxiang , Zhang Mingyuan , Lu Lu , Xu Hongfeng , Xiao Zuoyi , Liu Sa , Gao Shiping , Yu Zhihui
Published: May 2018

Copper sulfide‐active carbon (CuS‐AC) with a three‐dimensional (3D) porous structure is fabricated based on AC‐supported CuS nanosheets by using a solvothermal method and used in a high‐performance asymmetric supercapacitor devices to enhance the specific capacitance, cycling stability, and energy density. The CuS nanosheets form an array on the AC layer, and the two kinds of materials are ideally combined, leading to increased conductivity and enlarged electroactive surface area of the electrode materials. Moreover, the 3D CuS‐AC porous structure exhibited excellent electrochemical energy storage properties with large specific capacitance (247 F g−1 at a current density of 0.5 A g−1), high energy density (24.88 Wh kg−1 at the power density of 800 W kg−1), and good long‐term cycling stability (92% capacitance retention after 5000 cycles). This superior electrochemical performance can be ascribed to the high pseudocapacitance of CuS and large surface area from AC. The experimental results indicate that the hierarchical nanostructure design of CuS grown on AC exhibits considerable potential for supercapacitor applications.
Outstanding Chiroptical Features of Thin Films of Chiral Oligothiophenes
Authors: Albano Gianluigi , Salerno Francesco , Portus Lorenzo , Porzio William , Aronica Laura Antonella , Di Bari Lorenzo
Published: May 2018

A chiral benzo[1, 2‐b:4,5‐b′]dithiophene‐based oligothiophene with the very uncommon chiroptical property of signal inversion on sample flipping was recently described. This property is due to the interference between linear dichroism and linear birefringence, called LDLB effect, which is theoretically well understood, but to date very rarely reported in the literature. Samples with very large LDLB effect lead to the unique possibility of discriminating the direction of sample illumination (i. e., from the front or back). This article presents a set of analogue compounds, in which small structural changes are introduced to uncover which factors determine the very large LDLB effect or true circular dichroism connected to supramolecular chirality. It also reveals the impact of the deposition technique, in which spin coating may exert a primary role, and results in films with outstanding chiroptical features. These features are made even more relevant due to the semiconducting properties of oligothiophenes, which are interesting for optical sensing applications.
Highly secure palmprint based biometric template using fuzzy vault
Authors: Sujitha V. , Chitra D.
Published: May 2018

Biometric cryptosystem is an integrated system of cryptography with biometric features which is considered to be a promising component of template security. This paper presents a novel method for biometric cryptosystem based on fuzzy vault using palmprint features. Initially, pre‐processing is performed to remove noise in palmprint enrolled image and to pre‐align image automatically. Bottom‐hat filtering is employed for the feature extraction from the palmprint images. A polynomial is evaluated from the secret key and this polynomial is used to generate projections from palmprint features. Fuzzy vault is created by combining projected points with randomly generated dummy or chaff points. During decoding process, matching scores are calculated by comparing the query feature and stored vault. The vault is successfully decoded when the matched scores should be greater than a predefined threshold value. Experiments were conducted on CASIA database. Simulation result demonstrates that the proposed method gives better performance than other methods and improves the robustness against some security attacks.
Optimally bipartitioning sparse matrices with reordering and parallelization
Authors: Mumcuyan Aras , Usta Baran , Kaya Kamer , Yenigün Hüsnü
Published: May 2018

A good task‐to‐processor assignment is crucial for parallel efficiency since the communication between the tasks is usually the main bottleneck for scalability. A fundamental approach to solve this problem is modeling the tasks as a hypergraph where the pins correspond to the tasks and the nets represent the communication among them. The vertices in this hypergraph is partitioned into a number of parts, which correspond to processors, in a way that the total number of vertices for each part is balanced and the amount of edges having endpoints in different parts is minimized. Sparse matrix‐vector multiplication is an extensively used kernel in many applications. Recently, a novel, purely combinatorial branch‐and‐bound–based approach has been proposed for sparse‐matrix bipartitioning which can handle hypergraphs that cannot be optimally partitioned by using existing methods due to the problem's complexity. Our work extends the previous study with three ideas. We use 1) matrix ordering techniques to use more information in the earlier branches of the tree, 2) a machine learning approach to choose an ordering based on the matrix features, and 3) a parallelization technique to search an optimal bipartitioning. As our experiments show, these techniques make the bipartitioning process significantly faster.
Template‐Assisted Fabrication of Nanostructured Arrays for Sensing Applications
Authors: Xu Shipu , Lei Yong
Published: May 2018

High sensitivity imposes strict requirements on a sensing platform, for which nanostructured arrays are promising candidates. The template‐assisted method is an effective strategy to prepare various nanostructured arrays, which are widely developed for different sensing applications. Herein, nanostructured array based sensing platforms prepared from four widely used templates, a colloidal monolayer, anodic aluminum oxide, block copolymer, and a nanoimprint mold, are reviewed. In a series of sensing applications (e.g., biosensing and gas sensing), the resulting nanostructure‐array‐based platforms are high sensitive owing to their advanced morphology features: 1) high‐density alignment of arrayed nanostructures, 2) high surface‐to‐volume ratio, and 3) convex‐rich morphology. In surface‐enhanced Raman spectroscopy (SERS) applications, noble‐metal particle arrays with high‐density alignment produce an enhanced SERS signal owing to a strong concentration of plasmonic resonance on the substrate. To sense biomolecules in solution and gaseous molecules, arrays with a high surface‐to‐volume ratio or convex‐rich morphology can sensitively respond to changes in the environment. Moreover, the nanostructure‐array‐based sensing platforms are divided into three types (0D, 1D, and 3D nanostructured arrays) to demonstrate the morphological origin of the sensing performances.
Photochemically Produced Singlet Oxygen: Applications and Perspectives
Authors: Pibiri Ivana , Buscemi Silvestre , Palumbo Piccionello Antonio , Pace Andrea
Published: May 2018

This Review aims to provide early stage researchers with an updated guide to applications of photochemically produced singlet oxygen and, at the same time, widen the experienced researcher's perspectives in a holistic approach to singlet oxygen chemistry. Without being exhaustive, literature between 2010 and early 2018 has been surveyed by focusing on a critical evaluation of new knowledge and applications. After an introductory section concerning singlet oxygen production, detection, and interactions with biological systems, subsequent sections describe current applications of singlet‐oxygen‐enabled technology. Besides strictly chemical synthesis applications, attention has been given to the usage of singlet oxygen in photochemically assisted therapies as well as in environmental remediation. Additionally, the potential of expanding singlet oxygen chemistry to unexplored fields has been discussed.
Nanocrystalline H‐RTH Zeolite: An Efficient Catalyst for the Low‐Temperature Dehydration of Ethanol to Ethene
Authors: Lee Jeong Hwan , Lee Sujin , Hong Suk Bong
Published: May 2018

The low‐temperature dehydration of bioethanol is an environmentally benign route to ethene production. Here we compare the catalytic properties of a series of cage‐based small‐pore zeolites with different framework structures, acid strengths, and/or crystallite sizes for ethanol dehydration at 200 °C under wet conditions (H2O/EtOH=0.2). Among the zeolites studied here, nanocrystalline H‐RTH was found to be considerably more effective than H‐mordenite, the best catalyst for this reaction known to date, which can be rationalized by product shape selectivity. Whereas the acidity of this zeolite also plays a crucial role in selectively forming ethene, its nanocrystallinity is primarily responsible for the observed high catalyst durability.
Low‐power, latch‐based multistage time‐to‐digital converter in 65 nm CMOS technology
Authors: Razmdideh Ramin , Saneei Mohsen
Published: May 2018

In this paper, a low‐power and high‐resolution latch‐based time‐to‐digital converter (TDC) based on a multistage scheme is proposed. The proposed multistage TDC includes coarse, middle, and fine stages. The coarse stage is a new design of the flash TDC that is implemented by latches without using the delay cell. Also, the middle stage is a new design of the Vernier TDC with employed latches. The fine stage comprises parallel latches with different input loads.
Adaptive hysteresis band current control‐based power conditioner to improve the power quality of V/V railway supply system
Authors: Beirami Amin , Feshki Farahani Hassan
Published: May 2018

With rapid development of high‐speed and high‐power railway systems, power quality problems such as negative sequence current, reactive power, and harmonic current caused by electric locomotives become more and more critical. Recently, a new low‐cost railway power conditioner has been proposed to solve the power quality problems in traction substations based on a half bridge converter. In this paper, an adaptive hysteresis current controller is presented to limit switching frequency variations in the half bridge converter‐based railway power compensators (HB‐RPC). Adaptive hysteresis current controller instantaneously calculates the hysteresis bandwidth which results in smoother and more constant switching frequency. In order to maintain the normal operation of HB‐RPC, compensation reference currents are extracted by considering DC‐link stabilization energy, DC‐link capacitors voltage balance, and instantaneous power theory. Also, a dynamic reference design approach has been used to regulate the DC‐link capacitor voltage. Finally, the simulation results in MATLAB\Simulink software have effectively verified the proposed control method.
Time‐reversal invariance of quantum kinetic equations II: Density operator formalism
Authors: Bonitz Michael , Scharnke Miriam , Schlünzen Niclas
Published: May 2018

Time‐reversal symmetry is a fundamental property of many quantum mechanical systems. The relation between statistical physics and time reversal is subtle, and not all statistical theories conserve this particular symmetry—most notably, hydrodynamic equations and kinetic equations such as the Boltzmann equation. Here, we consider quantum kinetic generalizations of the Boltzmann equation using the method of reduced density operators, leading to the quantum generalization of the Bogolyubov‐Born‐Green‐Kirkwood‐Yvon (BBGKY) hierarchy. We demonstrate that all commonly used approximations, including Vlasov; Hartree‐Fock; and the non‐Markovian generalizations of the Landau, T‐matrix, and Lenard‐Balescu equations, are originally time‐reversal invariant, and we formulate a general criterion for time reversibility of approximations to the quantum BBGKY hierarchy. Finally, we illustrate, through the example of the Born approximation, how irreversibility is introduced into quantum kinetic theory via the Markov limit, making the connection with the standard Boltzmann equation. This paper is a complement to paper I (Scharnke et al., J. Math. Phys., 2017, 58, 061903), where the time‐reversal invariance of quantum kinetic equations was analysed in the frame of the independent non‐equilibrium Green functions formalism.
Effect of the Boussinesq approximation: Turbulence studies with GRILLIX in slab geometry
Authors: Ross Alexander , Stegmeir Andreas , Coster David
Published: May 2018

The drift‐reduced global Braginskii system is implemented in GRILLIX, a plasma turbulence code that is able to treat diverted geometries by using the flux‐coordinate independent approach (FCI). We solve a four‐field model, evolving the density, the electron temperature, the vorticity, and parallel ion momentum. The difference between the system with the Boussinesq approximation (BS) and the full system (FS) is investigated. The Boussinesq approximation is widely used as it reduces the numerical and computational complexity significantly. In order to understand the impact of the Boussinesq approximation, a periodic flux tube geometry is chosen as the computational domain. The conservation of energy and particles is derived and tested within the code, both in FS and BS. Moreover, we will discuss how the Boussinesq approximation has subtle effects on the energy theorem of the model, and a conserved energy‐like quantity is only obtained if the Boussinesq approximation is applied in a consistent way. We will also present numerical and computational techniques in order to relax the Boussinesq approximation. The code is verified by the method of manufactured solutions, which yields the expected order of accuracy. A fundamental result found in the paper is that the Boussinesq approximation only has a minor effect on non‐linear simulations, at least in the regime studied here.
Efficient network coding techniques for time constrained multicast narrowband power line communications
Authors: Chiti Francesco , Fantacci Romano , Tani Andrea
Published: May 2018

Nowadays, power line communication (PLC) technology is receiving a renewed attention in many application fields. In particular, PLC is quite attractive for what concerns novel paradigms as smart microgrid systems and smart buildings. This paper deals with a proposal of a PLC scheme that efficiently allows multicast services based on the use of an efficient network coding (NC) scheme. Furthermore, an analytical approach is outlined to pursue the performance optimization of the proposed solution. Finally, the good behavior of the proposed NC approach is highlighted by presenting performance comparisons with the classical NC alternative.
Alterations in retinoic acid signaling affect the development of the mouse coronary vasculature
Authors: Wang Suya , Huang Weiliang , Castillo Hozana A. , Kane Maureen A. , Xavier‐Neto José , Trainor Paul A. , Moise Alexander R.
Published: May 2018

Background: During the final stages of heart development the myocardium grows and becomes vascularized by means of paracrine factors and cell progenitors derived from the epicardium. There is evidence to suggest that retinoic acid (RA), a metabolite of vitamin A, plays an important role in epicardial‐based developmental programming. However, the consequences of altered RA‐signaling in coronary development have not been systematically investigated. Results: We explored the developmental consequences of altered RA‐signaling in late cardiogenic events that involve the epicardium. For this, we used a model of embryonic RA excess based on mouse embryos deficient in the retinaldehyde reductase DHRS3, and a complementary model of embryonic RA deficiency based on pharmacological inhibition of RA synthesis. We found that alterations in embryonic RA signaling led to a thin myocardium and aberrant coronary vessel formation and remodeling. Both excess, and deficient RA‐signaling are associated with reductions in ventricular coverage and density of coronary vessels, altered vessel morphology, and impaired recruitment of epicardial‐derived mural cells. Using a combined transcriptome and proteome profiling approach, we found that RA treatment of epicardial cells influenced key signaling pathways relevant for cardiac development. Conclusions: Epicardial RA‐signaling plays critical roles in the development of the coronary vasculature needed to support myocardial growth. Developmental Dynamics 247:976‐991, 2018. © 2018 Wiley Periodicals, Inc.
Incremental benefit of drug therapies for chronic heart failure with reduced ejection fraction: a network meta‐analysis
Authors: Komajda Michel , Böhm Michael , Borer Jeffrey S. , Ford Ian , Tavazzi Luigi , Pannaux Matthieu , Swedberg Karl
Published: May 2018

Aims

A network meta‐analysis (NMA) of all recommended drug groups for the treatment of heart failure with reduced ejection fraction (HFrEF), including their combinations, was performed to assess the relative efficacy and incremental benefit.

Methods and results.

A search was made in biomedical databases for randomized controlled trials published between 1987 and 2017 on angiotensin‐converting enzyme inhibitors (ACEIs), beta‐blockers (BBs), angiotensin receptor blockers (ARBs), mineralocorticoid receptor antagonists (MRAs), ivabradine (IVA), or angiotensin receptor–neprilysin inhibitors (ARNI). A total of 58 relevant trials were identified. The relative efficacy of each treatment group (or combination) in terms of all‐cause mortality, cardiovascular mortality, all‐cause hospitalizations and hospitalizations for heart failure, per patient‐year of follow‐up, were combined in a random‐effects Bayesian NMA. The pairwise comparison between each regimen and for each outcome was estimated. The NMA was dominated by 15 large‐scale trials with between 1984 and 18 898 patient‐years of follow‐up. Combinations of drug groups showed incremental benefits on outcomes over single groups. The most effective combinations were ARNI+BB + MRA and ACEI+BB + MRA + IVA, showing reductions in all‐cause mortality (vs. placebo) of 62% and 59%, respectively; hazard ratios were 0.38 [credible interval (CrI) 0.20–0.65] and 0.41 (CrI 0.21–0.70); and in all‐cause hospitalizations with reductions of 42% for both. These two combinations were also the most effective for the other outcomes studied.

Conclusion

Our analysis shows that the incremental use of combinations of disease‐modifying therapies has resulted in the progressive improvement in mortality and hospitalization outcomes in HFrEF. Our findings support the current guideline recommendations.
Straightforward Synthesis of L‐PEI‐Coated Gold Nanoparticles and Their Biological Evaluation
Authors: Bouché Mathilde , Fournel Sylvie , Kichler Antoine , Selvam Tamilselvi , Gallani Jean‐Louis , Bellemin‐Laponnaz Stéphane
Published: May 2018

Functionalized gold nanoparticles receive much attention for biomedical applications thanks to their improved in vivo circulation time and colloidal stability. This work aimed at developing a simple and efficient synthetic route for synthesizing nanoparticles coated with linear polyethyleneimine for use as non‐toxic platforms in non‐viral gene delivery. We show that the reproducible one‐pot synthesis of gold nanoparticles stabilized with a biocompatible linear PEI yields nanodelivery devices offering a low toxicity and very good transfection efficiency.
Palladium/Lewis Acid Cocatalyzed Reductive Asymmetric Ring‐Opening Reaction of Azabenzonorbornadienes with Tertiary Amines as the Hydrogen Source
Authors: Zhang Dapeng , Khan Ruhima , Yang Fan , Zhang Xuexin , Shen Guoli , Gao Yang , Fan Ruifeng , Sun Weiqing , Fan Baomin
Published: May 2018

The reductive asymmetric ring‐opening reaction of azabenzonorbornadienes has been developed by using palladium and silver as a co‐catalytic system and various tertiary amines as the hydrogen source. A wide range of azabenzonorbornadienes that contain electron‐donating and electron‐withdrawing substituents performed well in the developed protocol to result in 1,2‐dihydronaphthalen‐1‐amine derivatives in excellent yields with good to high enantioselectivities.
Synthesis of Naphthoxazoles by Photocyclization of 4‐/5‐(Phenylethenyl)oxazoles
Authors: Šagud Ivana , Šindler‐Kulyk Marija , Škorić Irena , Kelava Vanja , Marinić Željko
Published: May 2018

Promising test results on the biological activity of our previously described naphtho[1,2‐d]oxazoles and heterobenz[1,2‐d]oxazoles, obtained by the photochemical cyclization of 5‐phenylethenyl‐ and 5‐heteroarylethenyloxazoles, prompted us to continue with the photochemical synthesis of substituted naphtho[1,2‐d]oxazoles, and to extend the photochemical cyclization to the synthesis of naphtho/heterobenz[2,1‐d]oxazoles from 4‐(aryl/heteroarylethenyl)oxazoles. The required p‐ and o‐phenyl‐substituted 5‐arylethenyloxazoles were prepared from the corresponding α,β‐unsaturated aldehydes and the TosMIC reagent (tosylmethyl isocyanide) by the Van Leusen reaction. The substituted 4‐(aryl/heteroarylethenyl)oxazoles were prepared by the Wittig reaction starting from various phosphonium salts and 2‐H/methyl‐4‐oxazolecarbaldehydes.