bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphodiesterase‐5 inhibition potentiates cerebrovascular reactivity in chronic traumatic brain injury
Authors: Kenney Kimbra , Amyot Franck , Moore Carol , Haber Margalit , Turtzo L. Christine , Shenouda Christian , Silverman Erika , Gong Yunhua , Qu Bao‐ Xi , Harburg Leah , Wassermann Eric M. , Lu Hanzhang , Diaz‐Arrastia Ramon 
Published: March 2018

AbstractBackgroundTraumatic cerebrovascular injury (TCVI), a common consequence of traumatic brain injury (TBI), presents an attractive therapeutic target. Because phosphodiesterase‐5 (PDE5) inhibitors potentiate the action of nitric oxide (NO) produced by endothelial cells, they are candidate therapies for TCVI. This study aims to: (1) measure cerebral blood flow (CBF), cerebrovascular reactivity (CVR), and change in CVR after a single dose of sildenafil (ΔCVR) in chronic TBI compared to uninjured controls; (2) examine the safety and tolerability of 8‐week sildenafil administration in chronic symptomatic moderate/severe TBI patients; and as an exploratory aim, (3) assess the effect of an 8‐week course of sildenafil on chronic TBI symptoms.MethodsForty‐six subjects (31 chronic TBI, 15 matched healthy volunteers) were enrolled. Baseline CBF and CVR before and after administration of sildenafil were measured. Symptomatic TBI subjects then completed an 8‐week double‐blind, placebo‐controlled, crossover trial of sildenafil. A neuropsychological battery and neurobehavioral symptom questionnaires were administered at each study visit.ResultsAfter a single dose of sildenafil, TBI subjects showed a significant increase in global CVR compared to healthy controls (P < 0.001, d = 0.9). Post‐sildenafil CVR maps showed near‐normalization of CVR in many regions where baseline CVR was low, predominantly within areas without structural abnormalities. Sildenafil was well tolerated. Clinical Global Impression (CGI) scale showed a trend toward clinical improvement while on sildenafil treatment.FindingsSingle‐dose sildenafil improves regional CVR deficits in chronic TBI patients. CVR and ΔCVR are potential predictive and pharmacodynamic biomarkers of PDE5 inhibitor therapy for TCVI. Sildenafil is a potential therapy for TCVI.
Boosting the Efficiency of Near‐Infrared Fluorescent OLEDs with an Electroluminescent Peak of Nearly 800 nm by Sensitizer‐Based Cascade Energy Transfer
Authors: Liu Tengxiao , Xie Guohua , Zhong Cheng , Gong Shaolong , Yang Chuluo 
Published: March 2018

AbstractA sensitization‐based cascade energy transfer channel is proposed to boost the electroluminescent performances of the solution‐processed near‐infrared organic light‐emitting devices (OLEDs) featuring an electroluminescent peak of 786 nm from a new fluorescent emitter of N4,N4,N9,N9‐tetra‐p‐tolylnaphtho[2,3‐c][1,2,5]thiadiazole‐4,9‐diamine (NZ2mDPA) with unique aggregation‐induced emission (AIE) property. The optimized device is composed of 4,4′‐N,N‐dicarbazole‐biphenyl (CBP) as the host, bis(2‐phenyl‐1,3‐benzothiozolato‐N,C2′)iridium (Ir(bt)2(acac)) as the sensitizer, and NZ2mDPA as the emitter, where the cascade energy transfer can occur via two steps realizing unexpected triplet–singlet energy transfer by the Förster mechanism. The first step features efficient triplet harvesting from CBP to Ir(bt)2(acac), and then the second step involves in resonant energy transfer from the phosphorescent sensitizer to the near‐infrared AIE emitter of NZ2mDPA, which finally endows two channels of harvesting singlet and triplet excitons. The unique scheme achieves not only more efficient Förster energy transfer but also the higher utilization efficiency of triplet excitons. As a result, the near‐infrared OLEDs can realize a factor of 2.7 enhancement of external quantum efficiency by employing the phosphor‐sensitized AIE lumogen compared with the commonly used binary host–guest system.
Flexible, Durable, and Unconditioned Superoleophobic/Superhydrophilic Surfaces for Controllable Transport and Oil–Water Separation
Authors: Li Feiran , Wang Ziran , Huang Suichu , Pan Yunlu , Zhao Xuezeng 
Published: March 2018

AbstractSuperoleophobic/superhydrophilic surfaces have incomparable advantages for oil–water separation and oil droplet manipulation; however, such surfaces are difficult to obtain on the basis of surface tension theory, and existing attempts are either not fully functional or are nondurable. Here, a solution to achieve the combination of superoleophobicity and superhydrophilicity by emphasizing the polar component of surface tension is proposed. The developed surfaces can be flexibly applied to almost any solid substrate and exhibit superoleophobic and instantaneous superhydrophilic property. The surfaces applied to certain substrates can be used for controllable oil transport, oil–water separation, and emulsion demulsification. Furthermore, a novel ferroconcrete‐like structure to substantially increase the durability of the developed surfaces without affecting the superwettability is developed. The coated steel meshes preserve the ability of the material to separate oil–water mixtures even after over 400 m abrasion, which can be a significant step toward its widespread application.
Large‐Area Reduced Graphene Oxide Composite Films for Flexible Asymmetric Sandwich and Microsized Supercapacitors
Authors: Wang Xinyu , Wan Fang , Zhang Linlin , Zhao Zifang , Niu Zhiqiang , Chen Jun 
Published: March 2018

AbstractAsymmetric supercapacitors have attracted tremendous attention in energy storage devices since they have an enhanced energy density in comparison with symmetric supercapacitor devices. Furthermore, the development of diverse and flexible electronic devices requires the asymmetric supercapacitor devices to be flexible and in various configurations. However, it is still a challenge to develop a universal strategy to obtain both capacitive and Faradic electrodes with various architectures. Herein, a spontaneously reducing/assembling strategy in an alkaline condition is developed to fabricate large‐area reduced graphene oxide (RGO) and RGO–metal oxide/hydroxide composite films or microsized structures. As a proof of concept, the large‐area pure RGO and RGO/Mn3O4 composite films with porous structure and superior mechanical property are achieved by such strategy. These RGO‐based films can directly serve as the anodes and cathodes of the flexible asymmetric film supercapacitors. Furthermore, the interdigital RGO and RGO/Mn3O4 patterns are also obtained via a selectively reducing/assembling process to achieve the asymmetric microsized supercapacitors. These asymmetric supercapacitors with different configurations possess good electrochemical performance and excellent flexibility. Therefore, such reducing and assembling strategy provides a route to achieve large‐area RGO‐based films and microsized structures for the applications in the various fields such as energy storage and photocatalysis.
Binding Sulfur‐Doped Nb2O5 Hollow Nanospheres on Sulfur‐Doped Graphene Networks for Highly Reversible Sodium Storage
Authors: Liu Fanfan , Cheng Xiaolong , Xu Rui , Wu Ying , Jiang Yu , Yu Yan 
Published: March 2018

AbstractOrthorhombic Nb2O5 (T‐Nb2O5) has recently attracted great attention for its application as an anode for sodium ion batteries (NIBs) owing to its patulous framework and larger interplanar lattice spacing. Sulfur‐doped T‐Nb2O5 hollow nanospheres (diameter:180 nm) uniformly encapsulate into sulfur‐doped graphene networks (denoted: S‐Nb2O5 HNS@S‐rGO) using hard template method. The 3D ordered porous structure not only provides good electronic transportation path but also offers outstanding ionic conductive channels, leading to an improved sodium storage performance. In addition, the introduction of sulfur to graphene and Nb2O5 leads to oxygen vacancy and enhanced electronic conductivity. The sodium storage performance of S‐Nb2O5 HNS@S‐rGO is unprecedented. It delivers a reversible capacity 215 mAh g−1 at 0.5 C over 100 cycles. In addition, it also possesses a great high‐rate capability, retaining a stable capacity of 100 mAh g−1 at 20 C after 3000 cycles. This design demonstrates the potential applications of Nb2O5 as anode for high performance NIBs.
2D Ruddlesden–Popper Perovskites Microring Laser Array
Authors: Zhang Haihua , Liao Qing , Wu Yishi , Zhang Zhaoyi , Gao Qinggang , Liu Peng , Li Meili , Yao Jiannian , Fu Hongbing 
Published: March 2018

Abstract3D organic–inorganic hybrid perovskites have featured high gain coefficients through the electron–hole plasma stimulated emission mechanism, while their 2D counterparts of Ruddlesden–Popper perovskites (RPPs) exhibit strongly bound electron–hole pairs (excitons) at room temperature. High‐performance solar cells and light‐emitting diodes (LEDs) are reported based on 2D RPPs, whereas light‐amplification devices remain largely unexplored. Here, it is demonstrated that ultrafast energy transfer along cascade quantum well (QW) structures in 2D RPPs concentrates photogenerated carriers on the lowest‐bandgap QW state, at which population inversion can be readily established enabling room‐temperature amplified spontaneous emission and lasing. Gain coefficients measured for 2D RPP thin‐films (≈100 nm in thickness) are found about at least four times larger than those for their 3D counterparts. High‐density large‐area microring arrays of 2D RPPs are fabricated as whispering‐gallery‐mode lasers, which exhibit high quality factor (Q ≈ 2600), identical optical modes, and similarly low lasing thresholds, allowing them to be ignited simultaneously as a laser array. The findings reveal that 2D RPPs are excellent solution‐processed gain materials potentially for achieving electrically driven lasers and ideally for on‐chip integration of nanophotonics.
A Cut‐and‐Paste Approach to 3D Graphene‐Oxide‐Based Architectures
Authors: Luo Chong , Yeh Che‐Ning , Baltazar Jesus M. Lopez , Tsai Chao‐Lin , Huang Jiaxing 
Published: March 2018

AbstractProperly cut sheets can be converted into complex 3D structures by three basic operations including folding, bending, and pasting to render new functions. Folding and bending are extensively employed in crumpling, origami, and pop‐up fabrications for 3D structures. Pasting joins different parts of a material together, and can create new geometries that are fundamentally unattainable by folding and bending. However, it has been much less explored, likely due to limited choice of weldable thin film materials and residue‐free glues. Here it is shown that graphene oxide (GO) paper is one such suitable material. Stacked GO sheets can be readily loosened up and even redispersed in water, which upon drying, restack to form solid structures. Therefore, water can be utilized to heal local damage, glue separated pieces, and release internal stress in bent GO papers to fix their shapes. Complex and dynamic 3D GO architectures can thus be fabricated by a cut‐and‐paste approach, which is also applicable to GO‐based hybrid with carbon nanotubes or clay sheets.
N‐Type 2D Organic Single Crystals for High‐Performance Organic Field‐Effect Transistors and Near‐Infrared Phototransistors
Authors: Wang Cong , Ren Xiaochen , Xu Chunhui , Fu Beibei , Wang Ruihao , Zhang Xiaotao , Li Rongjin , Li Hongxiang , Dong Huanli , Zhen Yonggang , Lei Shengbin , Jiang Lang , Hu Wenping 
Published: March 2018

AbstractOrganic field‐effect transistors and near‐infrared (NIR) organic phototransistors (OPTs) have attracted world's attention in many fields in the past decades. In general, the sensitivity, distinguishing the signal from noise, is the key parameter to evaluate the performance of NIR OPTs, which is decided by responsivity and dark current. 2D single crystal films of organic semiconductors (2DCOS) are promising functional materials due to their long‐range order in spite of only few molecular layers. Herein, for the first time, air‐stable 2DCOS of n‐type organic semiconductors (a furan‐thiophene quinoidal compound, TFT‐CN) with strong absorbance around 830 nm, by the facile drop‐casting method on the surface of water are successfully prepared. Almost millimeter‐sized TFT‐CN 2DCOS are obtained and their thickness is below 5 nm. A competitive field‐effect electron mobility (1.36 cm2 V−1 s−1) and high on/off ratio (up to 108) are obtained in air. Impressively, the ultrasensitive NIR phototransistors operating at the off‐state exhibit a very low dark current of ≈0.3 pA and an ultrahigh detectivity (D*) exceeding 6 × 1014 Jones because the devices can operate in full depletion at the off‐state, superior to the majority of the reported organic‐based NIR phototransistors.
Graphene Oxide Quantum Dots Reduce Oxidative Stress and Inhibit Neurotoxicity In Vitro and In Vivo through Catalase‐Like Activity and Metabolic Regulation
Authors: Ren Chaoxiu , Hu Xiangang , Zhou Qixing 
Published: March 2018

AbstractBoth oxidative stress and neurotoxicity are huge challenges to human health, and effective methods and agents for resisting these adverse effects are limited, especially in vivo. It is shown here that, compared to large graphene oxide (GO) nanosheets, GO quantum dots (GOQDs), as nanozymes, efficiently reduce reactive oxygen species (ROS) and H2O2 in 1‐methyl‐4‐phenyl‐pyridinium ion (MPP+)‐induced PC12 cells. In addition, GOQDs exert neuroprotective effects in a neuronal cell model by decreasing apoptosis and α‐synuclein. GOQDs also efficiently diminish ROS, apoptosis, and mitochondrial damage in zebrafish treated with MPP+. Furthermore, GOQDs‐pretreated zebrafish shows increased locomotive activity and Nissl bodies in the brain, confirming that GOQDs ameliorate MPP+‐induced neurotoxicity, in contrast to GO nanosheets. GOQDs contribute to neurotoxic amelioration by increasing amino acid metabolism, decreasing tricarboxylic acid cycle activity, and reducing steroid biosynthesis, fatty acid biosynthesis, and galactose metabolic pathway activity, which are related to antioxidation and neurotransmission. Meanwhile, H2O2 decomposition and Fenton reactions suggest the catalase‐like activity of GOQDs. GOQDs can translocate into zebrafish brains and exert catalase‐mimicking activity to resist oxidation in the intracellular environment. Unlike general nanomaterials, biocompatible GOQDs demonstrate their high potential for human health by reducing oxidative stress and inhibiting neurotoxicity.
Reduced contrast sensitivity among older women is associated with increased risk of cognitive impairment
Authors: Ward Michael E. , Gelfand Jeffrey M. , Lui Li‐Yung , Ou Yvonne , Green Ari J. , Stone Katie , Pedula Kathryn L. , Cummings Steven R. , Yaffe Kristine 
Published: March 2018

ObjectiveSeveral cross‐sectional studies have reported an association between visual contrast sensitivity (a functional measure of low contrast vision) and poor cognitive performance or dementia, but no studies have investigated this association prospectively in a population‐based cohort with final adjudication of mild cognitive impairment (MCI)/dementia.MethodsIn a prospective, community‐based study of aging women (Study of Osteoporotic Fractures), we analyzed whether visual contrast sensitivity was associated with increased risk of MCI or dementia and/or worse performance on various cognitive tests assessed 10 years later. Contrast sensitivity was assessed at baseline in each eye using a VISTECH VCTS 6500 wall chart. MCI/dementia was adjudicated by an expert panel. Multivariate logistic and linear regression models were analyzed.ResultsOf 1,352 white (88.2%) and African American (11.8%) women with a mean age of 77.7 years (standard deviation = 3.3), 536 (39.6%) went on to develop MCI/dementia over 10 years. MCI/dementia risk was more than doubled (odds ratio = 2.16, 95% confidence interval = 1.58–2.96) in women with the lowest quartile of contrast sensitivity compared to the highest (p < 0.0001 for the linear trend). Reduced baseline contrast sensitivity was also associated with lower performance on several cognitive measures assessed 10 years later.InterpretationAmong older women, reduced contrast sensitivity is associated with a greater risk of MCI/dementia. These findings suggest that visual system neurodegeneration or dysfunction may parallel or precede dementia‐related cortical or subcortical degeneration, and that contrast sensitivity testing may be useful in identifying aging adults at high risk for dementia. Ann Neurol 2018;83:730–738
Inflammatory intrathecal profiles and cortical damage in multiple sclerosis
Authors: Magliozzi Roberta , Howell Owain W. , Nicholas Richard , Cruciani Carolina , Castellaro Marco , Romualdi Chiara , Rossi Stefania , Pitteri Marco , Benedetti Maria Donata , Gajofatto Alberto , Pizzini Francesca B. , Montemezzi Stefania , Rasia Sarah , Capra Ruggero , Bertoldo Alessandra , Facchiano Francesco , Monaco Salvatore , Reynolds Richard , Calabrese Massimiliano 
Published: March 2018

ObjectiveGray matter (GM) damage and meningeal inflammation have been associated with early disease onset and a more aggressive disease course in multiple sclerosis (MS), but can these changes be identified in the patient early in the disease course?MethodsTo identify possible biomarkers linking meningeal inflammation, GM damage, and disease severity, gene and protein expression were analyzed in meninges and cerebrospinal fluid (CSF) from 27 postmortem secondary progressive MS and 14 control cases. Combined cytokine/chemokine CSF profiling and 3T magnetic resonance imaging (MRI) were performed at diagnosis in 2 independent cohorts of MS patients (35 and 38 subjects) and in 26 non‐MS patients.ResultsIncreased expression of proinflammatory cytokines (IFNγ, TNF, IL2, and IL22) and molecules related to sustained B‐cell activity and lymphoid‐neogenesis (CXCL13, CXCL10, LTα, IL6, and IL10) was detected in the meninges and CSF of postmortem MS cases with high levels of meningeal inflammation and GM demyelination. Similar proinflammatory patterns, including increased levels of CXCL13, TNF, IFNγ, CXCL12, IL6, IL8, and IL10, together with high levels of BAFF, APRIL, LIGHT, TWEAK, sTNFR1, sCD163, MMP2, and pentraxin III, were detected in the CSF of MS patients with higher levels of GM damage at diagnosis.InterpretationA common pattern of intrathecal (meninges and CSF) inflammatory profile strongly correlates with increased cortical pathology, both at the time of diagnosis and at death. These results suggest a role for detailed CSF analysis combined with MRI as a prognostic marker for more aggressive MS. Ann Neurol 2018 Ann Neurol 2018;83:739–755
Effective Equations for Repulsive Quasi‐One Dimensional Bose–Einstein Condensates Trapped with Anharmonic Transverse Potentials
Authors: Couto Hugo L. C. , Avelar Ardiley T. , Cardoso Wesley B. 
Published: March 2018

AbstractOne‐dimensional nonlinear Schrödinger equations are derived to describe the axial effective dynamics of cigar‐shaped atomic repulsive Bose‐Einstein condensates trapped with anharmonic transverse potentials. The accuracy of these equations in the perturbative, Thomas‐Fermi, and crossover regimes were verified numerically by comparing the ground‐state profiles, transverse chemical potentials and oscillation patterns with those results obtained for the full three‐dimensional Gross‐Pitaevskii equation. This procedure allows us to derive different patterns of 1D nonlinear models by the control of the transverse confinement even in the presence of an axial vorticity.
Controlled Chemoenzymatic Synthesis of Heparan Sulfate Oligosaccharides
Authors: Lu Weigang , Zong Chengli , Chopra Pradeep , Pepi Lauren E. , Xu Yongmei , Amster I. Jonathan , Liu Jian , Boons Geert‐Jan 
Published: March 2018

AbstractA chemoenzymatic approach has been developed for the preparation of diverse libraries of heparan sulfate (HS) oligosaccharides. It employs chemically synthesized oligosaccharides having a chemical entity at a GlcN residue, which in unanticipated manners influences the site of modification by NST, C5‐Epi/2‐OST and 6‐OST1/6‐OST3, thus resulting in oligosaccharides differing in N/O‐sulfation and epimerization pattern. The enzymatic transformations defined fine substrate requirements of NST, C5‐Epi, 2‐OST, and 6‐OST.
Solvent‐Dependent Asymmetric Synthesis of Alkynyl and Monofluoroalkenyl Isoindolinones by CpRhIII‐Catalyzed C−H Activation
Authors: Li Teng , Zhou Chao , Yan Xiaoqiang , Wang Jun 
Published: March 2018

AbstractThe asymmetric synthesis of alkynyl and monofluoroalkenyl isoindolinones from N‐methoxy benzamides and α,α‐difluoromethylene alkynes is enabled by C−H activation with a chiral CpRhIII catalyst. Remarkably, product formation is solvent‐dependent; alkynyl isoindolinones are afforded in MeOH (up to 86 % yield, 99.6 % ee) whereas monofluoroalkenyl isoindolinones are generated in iPrCN (up to 98:2 Z/E, 93 % yield, 86 % ee). Mechanistic studies revealed chiral allene and E‐configured alkenyl rhodium species as reaction intermediates. The latter is transformed into the corresponding Z‐configured monofluoroalkene upon protonation in the iPrCN system and into an alkyne by an unusual anti β‐F elimination in the MeOH system. Notably, kinetic resolution processes occur in this reaction. Despite the moderate enantiocontrol for the formation of the chiral allene, the Z‐monofluoroalkenyl isoindolinones and alkynyl isoindolinones were obtained in good enantiopurities by one or two sequential kinetic resolution processes.
Co‐Evolutionary Fitness Landscapes for Sequence Design
Authors: Tian Pengfei , Louis John M. , Baber James L. , Aniana Annie , Best Robert B. 
Published: March 2018

AbstractEfficient and accurate models to predict the fitness of a sequence would be extremely valuable in protein design. We have explored the use of statistical potentials for the coevolutionary fitness landscape, extracted from known protein sequences, in conjunction with Monte Carlo simulations, as a tool for design. As proof of principle, we created a series of predicted high‐fitness sequences for three different protein folds, representative of different structural classes: the GA (all‐α) and GB (α/β) binding domains of streptococcal protein G, and an SH3 (all‐β) domain. We found that most of the designed proteins can fold stably to the target structure, and a structure for a representative of each for GA, GB and SH3 was determined. Several of our designed proteins were also able to bind to native ligands, in some cases with higher affinity than wild‐type. Thus, a search using a statistical fitness landscape is a remarkably effective tool for finding novel stable protein sequences.
Efficient Light‐Induced pKa Modulation Coupled to Base‐Catalyzed Photochromism
Authors: Gurke Johannes , Budzák Šimon , Schmidt Bernd M. , Jacquemin Denis , Hecht Stefan 
Published: March 2018

AbstractPhotoswitchable acid–base pairs, whose pKa values can be reversibly altered, are attractive molecular tools to control chemical and biological processes with light. A significant, light‐induced pKa change of three units in aqueous medium has been realized for two thermally stable states, which can be interconverted using UV and green light. The light‐induced pKa modulation is based on incorporating a 3‐H‐thiazol‐2‐one moiety into the framework of a diarylethene photoswitch, which loses the heteroaromatic stabilization of the negatively charged conjugate base upon photochemical ring closure, and hence becomes significantly less acidic. In addition, the efficiency of the photoreactions is drastically increased in the deprotonated state, giving rise to catalytically enhanced photochromism. It appears that protonation has a significant influence on the shape of the ground‐ and excited‐state potential energy surfaces, as indicated by quantum‐chemical calculations.