bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ligand Design to Acquire Specificity to Intended G‐Quadruplex Structures
Authors: Asamitsu Sefan , Bando Toshikazu , Sugiyama Hiroshi 
Published: July 2018

AbstractA G‐quadruplex is a nucleic acid secondary structure that is adopted by guanine‐rich sequences, and is considered to be relevant in various pharmacological and biological contexts. G‐Quadruplexes have also attracted great attention in the field of DNA nanotechnology because of their extremely high thermal stability and the availability of many defined structures. To date, a large repertory of DNA/RNA G‐quadruplex‐interactive ligands has been developed by numerous laboratories. Several relevant reviews have also been published that have helped researchers to grasp the full scope of G‐quadruplex research from its outset to the present. This review focuses on the G‐quadruplex ligands that allow targeting of specific G‐quadruplexes. Moreover, unique ligands, successful methodologies, and future perspectives in relation to specific G‐quadruplex recognition are also addressed.
Identifying a Needle in a Haystack: Isolation and Structural Characterization of Er2C94 as the Carbide Er2C2@D3(85)‐C92
Authors: Stevenson Steven , Tepper Katelyn R. , Davison Cody M. , Powers Xian B. , Olmstead Marilyn M. , Balch Alan L. 
Published: July 2018

AbstractA method has been developed for isolating a pure sample of Er2C94 from the myriad of fullerenes and endohedral fullerenes that are formed in the electric arc process. Crystallographic analysis of Er2C94 in a cocrystal formed with Ni(OEP) reveals that the molecule is the carbide Er2C2@D3(85)‐C92. Crystals of Er2C2@D3(85)‐C92⋅Ni(octaethylporphyrin)⋅2 C7H8 are isostructural with those of Sm2@D3(85)‐C92⋅Ni(octaethylporphyrin)⋅2 (chlorobenzene). Comparisons are made between the four crystallographically characterized endohedrals (Er2C2@D3(85)‐C92, Gd2C2@D3(85)‐C92, La2C2@D3(85)‐C92, and Sm2@D3(85)‐C92) that utilize the chiral D3(85)‐C92 cage.
Amino‐Substituted 2,2′‐Bipyridine Ligands as Fluorescent Indicators for ZnII and Applications for Fluorescence Imaging of Prostate Cells
Authors: Turnbull William L. , Luyt Leonard G. 
Published: July 2018

AbstractZnII concentrations in malignant prostate tissues are much lower than in benign or healthy, suggesting that ZnII levels are a potential biomarker for prostate cancer (PCa). Five 2,2′‐bipyridine ligands were synthesized containing amino substituents with varying electron‐donating ability for investigation as fluorescent ZnII indicators. The excited state characteristics of the ligands were explored by UV/Vis and fluorescence spectroscopy. 3,3′‐Diamino‐2,2′‐bipyridine (1) was previously shown to be weakly fluorescent as a result of π→π* transitions. The other four ligands have properties consistent with an n→π* intraligand charge transfer excited state. Strongly donating amino and aminophenyl (2 and 4) substituents gave low quantum yields, while weaker donating benzimidazole substituents (6 and 7) gave high quantum yields. Absorption and fluorescence wavelengths underwent bathochromic shifts upon ZnII binding in a majority of cases. Quantum yields drastically increased upon ZnII binding for 1 and 2, but decreased for 4, 6, and 7. Compounds 6 and 7 were incubated with PC‐3, DU 145 and BPH‐1 cells to determine their ZnII sensing abilities in a biological system. Weak fluorescence was observed in BPH‐1 cells and subsequent incubation with ZnII caused fluorescence intensity to increase. No fluorescence was observed in PCa cell lines. Further investigation of these ligands may allow for quantitative determination of ZnII concentrations in ex vivo tissue samples.
The Dual Role of Gold(I) Complexes in Photosensitizer‐Free Visible‐Light‐Mediated Gold‐Catalyzed 1,2‐Difunctionalization of Alkynes: A DFT Study
Authors: Liu Yanhong , Yang Yiying , Zhu Rongxiu , Liu Chengbu , Zhang Dongju 
Published: July 2018

AbstractRecently, a photosensitizer‐free visible‐light‐mediated gold‐catalyzed 1,2‐difunctionalization of alkynes has been developed. However, mechanistic aspects of this unconventional photocatalytic reaction remain largely obscure. With the aid of density functional theory (DFT) and time‐dependent (TD)DFT calculations, we mimicked the photosensitizer‐free visible‐light‐mediated gold‐catalyzed 1,2‐difunctionalization of 1‐phenyl‐1‐hexyne and focused on two fundamental questions: how does photoredox catalysis occur without assistance of an exogenous photosensitizer under visible light irradiation, and what is the detailed mechanism of the gold‐catalyzed 1,2‐difunctionalization of alkynes? The results reveal the dual role of the gold(I) complex in light‐harvesting and catalysis, where a charge‐transfer (CT) complex formed by the association of gold(I) catalyst with PhN2BF4 acts as a photosensitizer, which can undergo an electronic transition between the gold(I) moiety and PhN2BF4 of the CT complex into an excited electronic state and afford a charge‐transfer exciplex. The oxidative quenching of the exciplex generates the gold(II) species and diazobenzene radical. The subsequent catalytic cycle proceeds via two parallel pathways, involving the radical addition to gold(II) and gold(I) centers, respectively, and in these two pathways the reductive elimination of gold(III) species is identified as the rate‐determining step of the whole reaction. The present study could provide a new understanding for exogenous‐photosensitizer‐free visible‐light‐mediated gold‐catalyzed processes.
Metal–Organic Frameworks with Organogold(III) Complexes for Photocatalytic Amine Oxidation with Enhanced Efficiency and Selectivity
Authors: Han Qing , Wang Yue‐Lin , Sun Min , Sun Chun‐Yi , Zhu Shan‐Shan , Wang Xin‐Long , Su Zhong‐Min 
Published: July 2018

AbstractLuminescent organogold(III) complex AuIII with highly emissive triplet excited state was encapsulated in two metal–organic frameworks (MOFs) with different pore sizes and structures (MOF1 and ZJU‐28). Compared with the AuIII complex in solution, the resultant composites AuIII@MOF1 and AuIII@ZJU‐28 exhibit enhanced emission intensity, lifetime, and quantum yield. Under irradiation, AuIII@MOFs are efficient, selective, and recyclable catalysts for light‐induced aerobic C−N bond formation. When used as a heterogeneous catalyst for oxidizing secondary amines to the corresponding imines, AuIII@ZJU‐28 achieved high TONs of 876–1548, which are about 2.8–3.5 times higher than that of the homogenous AuIII complex. In addition, different selectivities in oxidizing mixed substrates is realized by means of different host MOFs, and thus encapsulating the AuIII complex in an appropriate MOF allowed the desired product to be obtained. Inherent shortcomings of homogeneous catalysts in cyclic use are also overcome by using composite catalysts, and high conversion of the AuIII@ZJU‐28 catalyst was still observed after ten cycles.
A 3D face registration algorithm based on conformal mapping
Authors: Qian Kun , Su Kehua , Zhang Jialing , Li Yinghua 
Published: July 2018

SummaryRecently, 3D facial datasets are more easily available, and at the same time, the research of 3D face becomes more and more important. One of the most important research fields is 3D face registration, which plays an important role in face recognition, face shape analysis, and face animation. However, one of the most challenging issues in 3D face registration is to obtain a unique mapping for faces with different expression and landmark constraints. In this paper, we propose a novel conformal mapping algorithm to deal with the 3D face registration. Besides, the calculation is about harmonic energy, which makes our method applicable to low‐quality meshes. We begin with a harmonic mapping, then minimize the harmonic energy by a specific boundary condition on surfaces, and to obtain the conformal mapping, finally, we use a landmark‐constrained surface registration algorithm to register faces. Numerical experiments on various surfaces demonstrate the efficiency and robustness of our method.
Leveraging OSD+ devices for implementing a high‐throughput parallel file system
Authors: Piernas Juan , González‐Férez Pilar 
Published: July 2018

SummaryOSD+s are enhanced object‐based storage devices (OSDs) able to deal with both data and metadata operations via data and directory objects, respectively. So far, we have focused on designing and implementing efficient directory objects in OSD+s. This paper, however, presents our work on also supporting data objects and describes how the coexistence of both kinds of objects in each OSD+ is profited to efficiently implement data objects and to speed up some common file operations. We compare our OSD+‐based Fusion Parallel File System (FPFS) with Lustre and OrangeFS through different microbenchmarks and HPCS‐IO scenarios. Results show that FPFS provides a throughput up to 37× better than Lustre and up to 95× better than OrangeFS for metadata workloads. FPFS also provides 34% more bandwidth than OrangeFS for data workloads and competes with Lustre in data writes. Results also show serious scalability problems in Lustre and OrangeFS that limit their performance.
HaDaap: A hotness‐aware data placement strategy for improving storage efficiency in heterogeneous Hadoop clusters
Authors: Xiong Runqun , Du Yao , Jin Jiahui , Luo Junzhou 
Published: July 2018

SummaryEnterprises increasingly use the Hadoop Distributed File System (HDFS) to manage and store big data for many applications. However, HDFS uses triple replication, leading to staggering data center storage costs. As big data increases in volume and its heat levels becomes more sensitive, there comes a point where storing so much cold data actually makes it less accessible and more expensive. Meanwhile, as data centers expand, the heterogeneity of nodes also becomes an issue. Rack‐aware data placement adopted by HDFS results in an unbalanced load and uneven resource allocation because it ignores the data nodes' heterogeneity. Here, we attempt to resolve these problems by proposing a hotness‐aware data placement strategy (named HaDaap). In HaDaap, the first step is to use a hotness‐aware data clustering algorithm to set the data's degree of heat. Then, cold data (with a redundancy of erasure code) are placed through a Double Sort Exchange algorithm to reduce storage costs and increase data availability. Finally, hot data are placed via a dynamic replication placement mechanism that comprehensively factors availability, load, and storage costs. Experimental results show that with these enhancements, HaDaap uses resources rationally and substantially reduces storage costs by considering the difference of data hotness in heterogeneous Hadoop clusters.
Non‐Pairwise Interactions in Parahydrogen Experiments: Nuclear Exchange of Single Protons Enables Bulk Water Hyperpolarization
Authors: Emondts Meike , Schikowski Daniel , Klankermayer Jürgen , Schleker P. Philipp M. 
Published: July 2018

AbstractHyperpolarization with parahydrogen (p‐H2) is a fast developing field in NMR, which enables overcoming the inherent low sensitivity of this important technique. The hyperpolarization of solvents, particularly of water, offers a wide range of applications for structural investigations of macromolecules and biomedical imaging. Until lately, only organic solvents could be polarized by means of parahydrogen via coherent redistribution of polarization (SABRE mechanism). In this study, we investigate in detail the mechanism of the recently reported bulk water hyperpolarization with a combination of theoretical and experimental methods, finally showing a chemical exchange pathway of single protons as basis for the enhancement. The prerequisites for preserving hyperpolarization upon separation of the two hydrogen atoms of p−H2 are demonstrated by theoretical examinations of the boundary conditions for the hyperpolarization experiments in accordance with the OneH−PHIP theory. These findings yielded the proposal of the novel NEPTUN mechanism (Nuclear Exchange Polarization by Transposing Unattached Nuclei) as the non‐hydrogenative equivalent to the established OneH−PHIP and thus the missing link in parahydrogen hyperpolarization theory.
A Stable and Efficient Cathode for Fluorine‐Containing Proton‐Conducting Solid Oxide Fuel Cells
Authors: Xie Yun , Shi Nai , Huan Daoming , Tan Wenzhou , Zhu Junfa , Zheng Xusheng , Pan Haibin , Peng Ranran , Xia Changrong 
Published: July 2018

AbstractSubstitution of anions such as F− and Cl− can effectively improve the stability of proton‐conducting electrolytes at no expense to proton conduction. However, during operation, F− and Cl− in electrolytes can transfer to the cathodes, which reduces the stability of the electrolytes. In this work, F−‐doped Ba0.5Sr0.5Co0.8Fe0.2O3−δ [Ba0.5Sr0.5Co0.8Fe0.2O2.9−δF0.1 (F‐BSCF)] was prepared as a potential cathode for proton‐conducting solid oxide fuel cells with BaCe0.8Sm0.2F0.1O2.85 electrolyte. The incorporation of F− in the cathode depressed F− diffusion from the electrolyte and improved the stability of button cells. Temperature‐changing X‐ray photoelectron spectroscopy and electronic conductivity relaxation results demonstrated that the incorporation of F− enhanced the oxygen incorporation kinetics at intermediate temperatures and improved the cathode catalytic performance. Moreover, a button cell prepared with this novel cathode was stable for 270 h at a current density of 300 mA cm−2 and 700 °C, which was much superior than those containing a BSCF cathode.
A Two‐Step Oxidative Cleavage of 1,2‐Diol Fatty Esters into Acids or Nitriles by a Dehydrogenation–Oxidative Cleavage Sequence
Authors: Guicheret Boris , Bertholo Yann , Blach Philippe , Raoul Yann , Métay Estelle , Lemaire Marc 
Published: July 2018

AbstractDehydrogenative oxidation of vicinal alcohols catalyzed by a commercially 64 wt.% Ni/SiO2 catalyst leads to the formation of α‐hydroxyketone. This first step was developed without additional solvent according to two protocols: “under vacuum” or “with an olefin scavenger”. The synthesis of ketols was carried out with good conversions and selectivities. The recyclability of the supported nickel was also studied. Acyloin was then cleaved with oxidative reagent “formic acid/hydrogen peroxide”, which is cheap and can be used on a large scale for industrial oxidation processes. The global yield of this sequential system was up to 80 % to pelargonic acid and azelaic acid monomethyl ester without intermediate purification. By treating the acyloin intermediate with hydroxylamine, nitriles were obtained with a good selectivity.
On the security and improvement of privacy‐preserving 3‐factor authentication scheme for TMIS
Authors: Wei Jianghong , Liu Wenfen , Hu Xuexian 
Published: July 2018

SummaryThe telecare medicine information system (TMIS) enables patients from different regions to remotely share the same telecare services, which significantly enhances the quality and effectiveness of medical treatment. On the other hand, patients' electronic health records usually involve their privacy information, they thus hesitate to directly transmit these information in TMIS over the public network due to the threat of privacy disclosure. The authenticated key agreement, as a core building of securing communications over the public network, is considered to be necessary for strengthening the security of TMIS. Recently, we note Zhang et al introduced a 3‐factor authenticated key agreement scheme for TMIS and asserted that the proposed scheme can resist various well‐known attacks. Unfortunately, in this paper, we point out that the scheme of Zhang et al cannot achieve the claimed security guarantees. Specifically, their scheme is vulnerable to offline password/identity guessing attack and user/server impersonation attack. To conquer the above security pitfalls, we put forward a new 3‐factor authenticated key agreement scheme with privacy preservation for TMIS. The security evaluation and performance discussion indicate that our scheme can be free from those well‐known and classical attacks including offline guessing attack and impersonation attack, without increasing additional computation cost when compared with related works. Consequently, the new authentication scheme would be more desirable for securing communications in TMIS.
Multimode precoding for crosstalk mitigation in ultra‐broadband DSL systems
Authors: Ng Yin Hoe , Chuah Teong Chee , Zainal Abidin Ahmadun Nijar , Hashim Nabihah , Asrokin Azhari 
Published: July 2018

SummaryThe achievable downstream bit‐rate performance of digital subscriber line (DSL) channels using low‐complexity linear precoders is suboptimal when the row‐wise diagonally dominant property of the channel matrix does not hold at high frequencies anticipated to be exploited in future‐generation DSL systems, while the optimal nonlinear precoder is computationally demanding. In this paper, we propose two multimode precoders, which are operable in four modes on each tone. Specifically, the proposed precoding strategies exploit the insertion loss and crosstalk information inferred from the channel matrix to execute mode selection for all the transmission tones. The computational complexity of the proposed multimode precoders is derived and compared with existing precoders. Simulation results show that the proposed precoders can achieve near‐optimal performance at a lower computational complexity.
Successful use of electroconvulsive therapy in a patient with anorexia nervosa and severe acute‐onset obsessive–compulsive disorder
Authors: Sağlam Tarık , Aksoy Poyraz Cana , Poyraz Burç Ç. , Tosun Musa 
Published: July 2018

AbstractAnorexia nervosa (AN) is a complex condition that is often accompanied by several serious comorbidities that may require a variety of treatment modalities throughout the course of the illness. Obsessive–compulsive disorder (OCD), which is common in patients with AN, may occasionally cause serious interruptions to the daily functioning of the patient. We report on a 24‐year‐old male patient with chronic AN. During the beginning of his illness, he had a major depressive episode that was followed by AN onset. Throughout his illness, he also experienced chronic moderate depressive symptoms and later developed severe OCD. He experienced complete remission from the OCD and an improved mood after undergoing a course of bilateral electroconvulsive therapy (ECT). His OCD symptoms did not recur during the first year of follow‐up. ECT may prove to be a fast and effective treatment strategy for severe and disabling acute‐onset OCD that occurs during the course of comorbid AN. The case described herein shows how a comorbid psychiatric disorder in a patient suffering from chronic AN may disrupt the daily functioning of the patient if it is not urgently treated.
Blimp‐1 induces and Hobit maintains the cytotoxic mediator granzyme B in CD8 T cells
Authors: Kragten Natasja A.M. , Behr Felix M. , Vieira Braga Felipe A. , Remmerswaal Ester B. M. , Wesselink Thomas H. , Oja Anna E. , Hombrink Pleun , Kallies Axel , van Lier Rene A.W. , Stark Regina , van Gisbergen Klaas P.J.M. 
Published: July 2018

AbstractCD8 T cells acquire cytotoxic molecules including granzyme B during effector differentiation. Both tissue‐resident memory CD8 T cells (Trm) and circulating CD45RA+ effector‐type T cells (Temra) cells have the ability to retain granzyme B protein expression into the memory phase, but it is unclear how this persistence of cytolytic activity is regulated during steady state. Previously, we have described that the transcriptional regulators Hobit and Blimp‐1 have overlapping target genes that include granzyme B, but their impact on the regulation of cytotoxicity in Trm and Temra cells during homeostasis has remained unclear. We examined the expression regulation of Hobit and Blimp‐1 in murine and human CD8 T‐cells to determine their timeframe of activity. While Blimp‐1 mRNA was expressed throughout effector and memory T cells, Blimp‐1 protein, was only transiently expressed during the effector stage. In contrast, Hobit mRNA and protein expression was stably maintained during quiescence, but downregulated after activation. Notably, Blimp‐1 was required for expression of granzyme B in murine effector T cells and Trm, while Hobit specifically regulated granzyme B in murine Trm during the memory phase. These findings suggest that Blimp‐1 initiates cytotoxic effector function and that Hobit maintains cytotoxicity in a deployment‐ready modus in Trm.
X‐ray Nano Computed Tomography of Electrospun Fibrous Mats as Flow Battery Electrodes
Authors: Jervis Rhodri , Kok Matt D. R. , Montagut Julian , Gostick Jeff T. , Brett Dan J. L. , Shearing Paul R. 
Published: July 2018

AbstractMany electrochemical energy storage and conversion devices employ porous media as electrodes, gas diffusion layers or separators. Recently, electrospinning has received significant attention as a way to generate nano‐fibers of polymers with controlled morphology and properties that, once carbonised, can act as conductive and porous media for electrochemical energy devices. The recent advances in X‐ray computed tomography have led the technique to be widely used in the characterisation of energy technologies and porous media as it offers a uniquely non‐destructive insight into the 3D microstructure of materials. Here we present electrospun fibrous mats with uncontrolled, controlled and aligned morphology for use as redox flow battery electrodes and, for the first time, obtain ultra‐high resolution nano‐tomographic X‐ray imaging of the materials using a lab source. The virtual 3D volumes enable extraction of parameters that would not be possible via other characterisation routes.
Multivariate constrained robust M‐regression for shaping forward curves in electricity markets
Authors: Leoni Peter , Segaert Pieter , Serneels Sven , Verdonck Tim 
Published: July 2018

AbstractIn this paper, a multivariate constrained robust M‐regression method is developed to estimate shaping coefficients for electricity forward prices. An important benefit of the new method is that model arbitrage can be ruled out at an elementary level, as all shaping coefficients are treated simultaneously. Moreover, the new method is robust to outliers, such that the provided results are stable and not sensitive to isolated sparks or dips in the market. An efficient algorithm is presented to estimate all shaping coefficients at a low computational cost. To illustrate its good performance, the method is applied to German electricity prices.