bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving resolution in quantum subnanometre-gap tip-enhanced Raman nanoimaging
Authors: Zhang Yingchao , Voronine Dmitri V. , Qiu Shangran , Sinyukov Alexander M. , Hamilton Mary , Liege Zachary , Sokolov Alexei V. , Zhang Zhenrong , Scully Marlan O. 
Published: May 2016

AbstractTwo-dimensional (2D) materials beyond graphene such as transition metal dichalcogenides (TMDs) have unique mechanical, optical and electronic properties with promising applications in flexible devices, catalysis and sensing. Optical imaging of TMDs using photoluminescence and Raman spectroscopy can reveal the effects of structure, strain, doping, edge states and surface functionalization from materials to bioscience. However, Raman signals are inherently weak and so far have been limited in spatial resolution in TMDs to a few hundred nanometres which is much larger than the intrinsic scale of these effects. Here we overcome the diffraction limit by using resonant tip-enhanced Raman scattering (TERS) of few-layer MoS2 and obtain nanoscale optical images with ~20 nm spatial resolution. This becomes possible due to electric field enhancement in an optimized subnanometre-gap resonant tip-substrate configuration. We investigate the limits of signal enhancement by varying the tip-sample gap with sub-Angstrom precision and observe a quantum quenching behavior, as well as a Schottky-Ohmic transition, for subnanometre gaps, which enable surface mapping based on this new contrast mechanism. This quantum regime of plasmonic gap-mode enhancement with a few nanometre thick MoS2 junction may be used for designing new quantum optoelectronic devices and sensors with a wide range of applications.
Phylogeographic analysis of hemorrhagic fever with renal syndrome patients using multiplex PCR-based next generation sequencing
Authors: Kim Won-Keun , Kim Jeong-Ah , Song Dong Hyun , Lee Daesang , Kim Yong Chul , Lee Sook-Young , Lee Seung-Ho , No Jin Sun , Kim Ji Hye , Kho Jeong Hoon , Gu Se Hun , Jeong Seong Tae , Wiley Michael , Kim Heung-Chul , Klein Terry A. , Palacios Gustavo , Song Jin-Won 
Published: May 2016

AbstractEmerging and re-emerging infectious diseases caused by RNA viruses pose a critical public health threat. Next generation sequencing (NGS) is a powerful technology to define genomic sequences of the viruses. Of particular interest is the use of whole genome sequencing (WGS) to perform phylogeographic analysis, that allows the detection and tracking of the emergence of viral infections. Hantaviruses, Bunyaviridae, cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) in humans. We propose to use WGS for the phylogeographic analysis of human hantavirus infections. A novel multiplex PCR-based NGS was developed to gather whole genome sequences of Hantaan virus (HTNV) from HFRS patients and rodent hosts in endemic areas. The obtained genomes were described for the spatial and temporal links between cases and their sources. Phylogenetic analyses demonstrated geographic clustering of HTNV strains from clinical specimens with the HTNV strains circulating in rodents, suggesting the most likely site and time of infection. Recombination analysis demonstrated a genome organization compatible with recombination of the HTNV S segment. The multiplex PCR-based NGS is useful and robust to acquire viral genomic sequences and may provide important ways to define the phylogeographical association and molecular evolution of hantaviruses.
Ultra-high density optical data storage in common transparent plastics
Authors: Kallepalli Deepak L. N. , Alshehri Ali M. , Marquez Daniela T. , Andrzejewski Lukasz , Scaiano Juan C. , Bhardwaj Ravi 
Published: May 2016

AbstractThe ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc.
Involvement of the P2X7-NLRP3 axis in leukemic cell proliferation and death
Authors: Salaro Erica , Rambaldi Alessia , Falzoni Simonetta , Amoroso Francesca Saveria , Franceschini Alessia , Sarti Alba Clara , Bonora Massimo , Cavazzini Francesco , Rigolin Gian Matteo , Ciccone Maria , Audrito Valentina , Deaglio Silvia , Pelegrin Pablo , Pinton Paolo , Cuneo Antonio , Di Virgilio Francesco 
Published: May 2016

AbstractLymphocyte growth and differentiation are modulated by extracellular nucleotides and P2 receptors. We previously showed that the P2X7 receptor (P2X7R or P2RX7) is overexpressed in circulating lymphocytes from chronic lymphocytic leukemia (CLL) patients. In the present study we investigated the P2X7R/NLRP3 inflammasome axis in lymphocytes from a cohort of 23 CLL patients. P2X7R, ASC and NLRP3 were investigated by Western blot, PCR and transfection techniques. P2X7R was overexpressed and correlated with chromosome 12 trisomy in CLL patients. ASC mRNA and protein were also overexpressed. On the contrary, NLRP3 was dramatically down-modulated in CLL lymphocytes relative to lymphocytes from healthy donors. To further investigate the correlation between P2X7R, NLRP3 and cell growth, NLRP3 was silenced in THP-1 cells, a leukemic cell line that natively expresses both NLRP3 and P2X7R. NLRP3 silencing enhanced P2X7R expression and promoted growth. On the contrary, NLRP3 overexpression caused accelerated apoptosis. The P2X7R was also up-modulated in hematopoietic cells from NLRP3-KO mice. In conclusion, we show that NLRP3 down-modulation stimulates P2X7R expression and promotes growth, while NLRP3 overexpression inhibits cell proliferation and stimulates apoptosis. These findings suggest that NLRP3 is a negative regulator of growth and point to a role of the P2X7R/NLRP3 axis in CLL.
A method of undifferenced ambiguity resolution for GPS+GLONASS precise point positioning
Authors: Yi Wenting , Song Weiwei , Lou Yidong , Shi Chuang , Yao Yibin 
Published: May 2016

AbstractInteger ambiguity resolution is critical for achieving positions of high precision and for shortening the convergence time of precise point positioning (PPP). However, GLONASS adopts the signal processing technology of frequency division multiple access and results in inter-frequency code biases (IFCBs), which are currently difficult to correct. This bias makes the methods proposed for GPS ambiguity fixing unsuitable for GLONASS. To realize undifferenced GLONASS ambiguity fixing, we propose an undifferenced ambiguity resolution method for GPS+GLONASS PPP, which considers the IFCBs estimation. The experimental result demonstrates that the success rate of GLONASS ambiguity fixing can reach 75% through the proposed method. Compared with the ambiguity float solutions, the positioning accuracies of ambiguity-fixed solutions of GLONASS-only PPP are increased by 12.2%, 20.9%, and 10.3%, and that of the GPS+GLONASS PPP by 13.0%, 35.2%, and 14.1% in the North, East and Up directions, respectively.
RNAi down-regulation of cinnamate-4-hydroxylase increases artemisinin biosynthesis in Artemisia annua
Authors: Kumar Ritesh , Vashisth Divya , Misra Amita , Akhtar Md Qussen , Jalil Syed Uzma , Shanker Karuna , Gupta Madan Mohan , Rout Prashant Kumar , Gupta Anil Kumar , Shasany Ajit Kumar 
Published: May 2016

AbstractCinnamate-4-hydroxylase(C4H) convertstrans-cinnamic acid (CA) top-coumaric acid (COA) in the phenylpropanoid/lignin biosynthesis pathway. Earlier we reported increased expression ofAaCYP71AV1(an important gene of artemisinin biosynthesis pathway) caused by CA treatment inArtemisia annua. Hence,AaC4Hgene was identified, cloned, characterized and silenced inA. annuawith the assumption that the elevated internal CA due to knock down may increase the artemisinin yield. Accumulation oftrans-cinnamic acid in the plant due toAaC4Hknockdown was accompanied with the reduction ofp-coumaric acid, total phenolics, anthocyanin, cinnamate-4-hydroxylase (C4H) and phenylalanine ammonia lyase (PAL) activities but increase in salicylic acid (SA) and artemisinin. Interestingly, feedingtrans-cinnamic acid to the RNAi line increased the level of artemisinin along with benzoic (BA) and SA with no effect on the downstream metabolitesp-coumaric acid, coniferylaldehyde and sinapaldehyde, whereasp-coumaric acid feeding increased the content of downstream coniferylaldehyde and sinapaldehyde with no effect on BA, SA,trans-cinnamic acid or artemisinin. SA is reported earlier to be inducing the artemisinin yield. This report demonstrates the link between the phenylpropanoid/lignin pathway with artemisinin pathway through SA, triggered by accumulation oftrans-cinnamic acid because of the blockage at C4H.
Fiber-Type Random Laser Based on a Cylindrical Waveguide with a Disordered Cladding Layer
Authors: Zhang Wei Li , Zheng Meng Ya , Ma Rui , Gong Chao Yang , Yang Zhao Ji , Peng Gang Ding , Rao Yun Jiang 
Published: May 2016

AbstractThis letter reports a fiber-type random laser (RL) which is made from a capillary coated with a disordered layer at its internal surface and filled with a gain (laser dye) solution in the core region. This fiber-type optical structure, with the disordered layer providing randomly scattered light into the gain region and the cylindrical waveguide providing confinement of light, assists the formation of random lasing modes and enables a flexible and efficient way of making random lasers. We found that the RL is sensitive to laser dye concentration in the core region and there exists a fine exponential relationship between the lasing intensity and particle concentration in the gain solution. The proposed structure could be a fine platform of realizing random lasing and random lasing based sensing.
Synthesis and Characterization of an Alumina Forming Nanolaminated Boride: MoAlB
Authors: Kota Sankalp , Zapata-Solvas Eugenio , Ly Alexander , Lu Jun , Elkassabany Omar , Huon Amanda , Lee William E. , Hultman Lars , May Steve J. , Barsoum Michel W. 
Published: May 2016

AbstractThe ‘MAlB’ phases are nanolaminated, ternary transition metal borides that consist of a transition metal boride sublattice interleaved by monolayers or bilayers of pure aluminum. However, their synthesis and properties remain largely unexplored. Herein, we synthesized dense, predominantly single-phase samples of one such compound, MoAlB, using a reactive hot pressing method. High-resolution scanning transmission electron microscopy confirmed the presence of two Al layers in between a Mo-B sublattice. Unique among the transition metal borides, MoAlB forms a dense, alumina scale when heated in air. Like other alumina formers, the oxidation kinetics follow a cubic time-dependence. At room temperature, its resistivity is low (0.36–0.49 μΩm) and – like a metal – drops linearly with decreasing temperatures. It is also a good thermal conductor (35 Wm−1K−1at 26 °C). In the 25–1300 °C temperature range, its thermal expansion coefficient is 9.5 × 10−6K−1. Preliminary results suggest the compound is stable to at least 1400 °C in inert atmospheres. Moderately low Vickers hardness values of 10.6 ± 0.3 GPa, compared to other transition metal borides, and ultimate compressive strengths up to 1940 ± 103 MPa were measured at room temperature. These results are encouraging and warrant further study of this compound for potential use at high temperatures.
HIV-dependent depletion of influenza-specific memory B cells impacts B cell responsiveness to seasonal influenza immunisation
Authors: Wheatley Adam K. , Kristensen Anne B. , Lay William N. , Kent Stephen J. 
Published: May 2016

AbstractInfection with HIV drives significant alterations in B cell phenotype and function that can markedly influence antibody responses to immunisation. Anti-retroviral therapy (ART) can partially reverse many aspects of B cell dysregulation, however complete normalisation of vaccine responsiveness is not always observed. Here we examine the effects of underlying HIV infection upon humoral immunity to seasonal influenza vaccines. Serological and memory B cell responses were assessed in 26 HIV+ subjects receiving ART and 30 healthy controls immunised with the 2015 Southern Hemisphere trivalent inactivated influenza vaccine (IIV3). Frequencies and phenotypes of influenza hemagglutinin (HA)-specific B cells were assessed by flow cytometry using recombinant HA probes. Serum antibody was measured using hemagglutination inhibition assays. Serological responses to IIV3 were comparable between HIV+ and HIV− subjects. Likewise, the activation and expansion of memory B cell populations specific for vaccine-component influenza strains was observed in both cohorts, however peak frequencies were diminished in HIV+ subjects compared to uninfected controls. Lower circulating frequencies of memory B cells recognising vaccine-component and historical influenza strains were observed in HIV+ subjects at baseline, that were generally restored to levels comparable with HIV− controls post-vaccination. HIV infection is therefore associated with depletion of selected HA-specific memory B cell pools.
Scaling and universality in glass transition
Authors: de Candia Antonio , Fierro Annalisa , Coniglio Antonio 
Published: May 2016

AbstractKinetic facilitated models and the Mode Coupling Theory (MCT) model B are within those systems known to exhibit a discontinuous dynamical transition with a two step relaxation. We consider a general scaling approach, within mean field theory, for such systems by considering the behavior of the density correlator 〈q(t)〉 and the dynamical susceptibility 〈q2(t)〉 − 〈q(t)〉2. Focusing on the Fredrickson and Andersen (FA) facilitated spin model on the Bethe lattice, we extend a cluster approach that was previously developed for continuous glass transitions by Arenzon et al. (Phys. Rev. E 90, 020301(R) (2014)) to describe the decay to the plateau and consider a damage spreading mechanism to describe the departure from the plateau. We predict scaling laws, which relate dynamical exponents to the static exponents of mean field bootstrap percolation. The dynamical behavior and the scaling laws for both density correlator and dynamical susceptibility coincide with those predicted by MCT. These results explain the origin of scaling laws and the universal behavior associated with the glass transition in mean field, which is characterized by the divergence of the static length of the bootstrap percolation model with an upper critical dimension dc = 8.
Atomic-level structural and chemical analysis of Cr-doped Bi2Se3 thin films
Authors: Ghasemi A. , Kepaptsoglou D. , Collins-McIntyre L. J. , Ramasse Q. , Hesjedal T. , Lazarov V. K. 
Published: May 2016

AbstractWe present a study of the structure and chemical composition of the Cr-doped 3D topological insulator Bi2Se3. Single-crystalline thin films were grown by molecular beam epitaxy on Al2O3 (0001), and their structural and chemical properties determined on an atomic level by aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy. A regular quintuple layer stacking of the Bi2Se3 film is found, with the exception of the first several atomic layers in the initial growth. The spectroscopy data gives direct evidence that Cr is preferentially substituting for Bi in the Bi2Se3 host. We also show that Cr has a tendency to segregate at internal grain boundaries of the Bi2Se3 film.
Resolving metal-molecule interfaces at single-molecule junctions
Authors: Komoto Yuki , Fujii Shintaro , Nakamura Hisao , Tada Tomofumi , Nishino Tomoaki , Kiguchi Manabu 
Published: May 2016

AbstractElectronic and structural detail at the electrode-molecule interface have a significant influence on charge transport across molecular junctions. Despite the decisive role of the metal-molecule interface, a complete electronic and structural characterization of the interface remains a challenge. This is in no small part due to current experimental limitations. Here, we present a comprehensive approach to obtain a detailed description of the metal-molecule interface in single-molecule junctions, based on current-voltage (I-V) measurements. Contrary to conventional conductance studies, this I-V approach provides a correlated statistical description of both, the degree of electronic coupling across the metal-molecule interface and the energy alignment between the conduction orbital and the Fermi level of the electrode. This exhaustive statistical approach was employed to study single-molecule junctions of 1,4-benzenediamine (BDA), 1,4-butanediamine (C4DA) and 1,4-benzenedithiol (BDT). A single interfacial configuration was observed for both BDA and C4DA junctions, while three different interfacial arrangements were resolved for BDT. This multiplicity is due to different molecular adsorption sites on the Au surface namely on-top, hollow and bridge. Furthermore, C4DA junctions present a fluctuating I-V curve arising from the greater conformational freedom of the saturated alkyl chain, in sharp contrast with the rigid aromatic backbone of both BDA and BDT.
Interface Engineering for the Enhancement of Carrier Transport in Black Phosphorus Transistor with Ultra-Thin High-k Gate Dielectric
Authors: Ling Zhi-Peng , Zhu Jun-Tao , Liu Xinke , Ang Kah-Wee 
Published: May 2016

AbstractBlack phosphorus (BP) is the most stable allotrope of phosphorus which exhibits strong in-plane anisotropic charge transport. Discovering its interface properties between BP and high-k gate dielectric is fundamentally important for enhancing the carrier mobility and electrostatics control. Here, we investigate the impact of interface engineering on the transport properties of BP transistors with an ultra-thin hafnium-dioxide (HfO2) gate dielectric of ~3.4 nm. A high hole mobility of ~536 cm2V−1s−1 coupled with a near ideal subthreshold swing (SS) of ~66 mV/dec were simultaneously achieved at room temperature by improving the BP/HfO2 interface quality through thermal treatment. This is attributed to the passivation of phosphorus dangling bonds by hafnium (Hf) adatoms which produces a more chemically stable interface, as evidenced by the significant reduction in interface states density. Additionally, we found that an excessively high thermal treatment temperature (beyond 200 °C) could detrimentally modify the BP crystal structure, which results in channel resistance and mobility degradation due to charge-impurities scattering and lattice displacement. This study contributes to an insight for the development of high performance BP-based transistors through interface engineering.
HPTLC-aptastaining – Innovative protein detection system for high-performance thin-layer chromatography
Authors: Morschheuser Lena , Wessels Hauke , Pille Christina , Fischer Judith , Hünniger Tim , Fischer Markus , Paschke-Kratzin Angelika , Rohn Sascha 
Published: May 2016

AbstractProtein analysis using high-performance thin-layer chromatography (HPTLC) is not commonly used but can complement traditional electrophoretic and mass spectrometric approaches in a unique way. Due to various detection protocols and possibilities for hyphenation, HPTLC protein analysis is a promising alternative for e.g., investigating posttranslational modifications. This study exemplarily focused on the investigation of lysozyme, an enzyme which is occurring in eggs and technologically added to foods and beverages such as wine. The detection of lysozyme is mandatory, as it might trigger allergenic reactions in sensitive individuals. To underline the advantages of HPTLC in protein analysis, the development of innovative, highly specific staining protocols leads to improved sensitivity for protein detection on HPTLC plates in comparison to universal protein derivatization reagents. This study aimed at developing a detection methodology for HPTLC separated proteins using aptamers. Due to their affinity and specificity towards a wide range of targets, an aptamer based staining procedure on HPTLC (HPTLC-aptastaining) will enable manifold analytical possibilities. Besides the proof of its applicability for the very first time, (i) aptamer-based staining of proteins is applicable on different stationary phase materials and (ii) furthermore, it can be used as an approach for a semi-quantitative estimation of protein concentrations.
Surfactant-assisted Nanocasting Route for Synthesis of Highly Ordered Mesoporous Graphitic Carbon and Its Application in CO2 Adsorption
Authors: Wang Yangang , Bai Xia , Wang Fei , Qin Hengfei , Yin Chaochuang , Kang Shifei , Li Xi , Zuo Yuanhui , Cui Lifeng 
Published: May 2016

AbstractHighly ordered mesoporous graphitic carbon was synthesized from a simple surfactant-assisted nanocasting route, in which ordered mesoporous silica SBA-15 maintaining its triblock copolymer surfactant was used as a hard template and natural soybean oil (SBO) as a carbon precursor. The hydrophobic domain of the surfactant assisted SBO in infiltration into the template’s mesoporous channels. After the silica template was carbonized and removed, a higher yield of highly-ordered graphitic mesoporous carbon with rod-like morphology was obtained. Because of the improved structural ordering, the mesoporous carbon after amine modification could adsorb more CO2 compared with the amine-functionalized carbon prepared without the assistance of surfactant.
Elastomeric Cellular Structure Enhanced by Compressible Liquid Filler
Authors: Sun Yueting , Xu Xiaoqing , Xu Chengliang , Qiao Yu , Li Yibing 
Published: May 2016

AbstractElastomeric cellular structures provide a promising solution for energy absorption. Their flexible and resilient nature is particularly relevant to protection of human bodies. Herein we develop an elastomeric cellular structure filled with nanoporous material functionalized (NMF) liquid. Due to the nanoscale infiltration in NMF liquid and its interaction with cell walls, the cellular structure has a much enhanced mechanical performance, in terms of loading capacity and energy absorption density. Moreover, it is validated that the structure is highly compressible and self-restoring. Its hyper-viscoelastic characteristics are elucidated.