bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth of semiconducting single-wall carbon nanotubes with a narrow band-gap distribution
Authors: Zhang Feng , Hou Peng-Xiang , Liu Chang , Wang Bing-Wei , Jiang Hua , Chen Mao-Lin , Sun Dong-Ming , Li Jin-Cheng , Cong Hong-Tao , Kauppinen Esko I. , Cheng Hui-Ming
Published: March 2016

The growth of high-quality semiconducting single-wall carbon nanotubes with a narrow band-gap distribution is crucial for the fabrication of high-performance electronic devices. However, the single-wall carbon nanotubes grown from traditional metal catalysts usually have diversified structures and properties. Here we design and prepare an acorn-like, partially carbon-coated cobalt nanoparticle catalyst with a uniform size and structure by the thermal reduction of a [Co(CN)6]3− precursor adsorbed on a self-assembled block copolymer nanodomain. The inner cobalt nanoparticle functions as active catalytic phase for carbon nanotube growth, whereas the outer carbon layer prevents the aggregation of cobalt nanoparticles and ensures a perpendicular growth mode. The grown single-wall carbon nanotubes have a very narrow diameter distribution centred at 1.7 nm and a high semiconducting content of >95%. These semiconducting single-wall carbon nanotubes have a very small band-gap difference of ∼0.08 eV and show excellent thin-film transistor performance.
Correction: Corrigendum: Precursor and mature NGF live tracking: one versus many at a time in the axons
Authors: Nadai Teresa De , Marchetti Laura , Rienzo Carmine Di , Calvello Mariantonietta , Signore Giovanni , Matteo Pierluigi Di , Gobbo Francesco , Turturro Sabrina , Meucci Sandro , Viegi Alessandro , Beltram Fabio , Luin Stefano , Cattaneo Antonino
Published: March 2016

Scientific Reports 6: Article number: 20272; published online: 01 February 2016; updated: 30 March 2016 This Article contains errors in Affiliation 3. The correct affiliation is listed below: Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12-56127 Pisa, Italy.
microRNA-146a promotes mycobacterial survival in macrophages through suppressing nitric oxide production
Authors: Li Miao , Wang Jinli , Fang Yimin , Gong Sitang , Li Meiyu , Wu Minhao , Lai Xiaomin , Zeng Gucheng , Wang Yi , Yang Kun , Huang Xi
Published: March 2016

Macrophages play a crucial role in host innate anti-mycobacterial defense, which is tightly regulated by multiple factors, including microRNAs. Our previous study showed that a panel of microRNAs was markedly up-regulated in macrophages upon mycobacterial infection. Here, we investigated the biological function of miR-146a during mycobacterial infection. miR-146a expression was induced both in vitro and in vivo after Mycobacterium bovis BCG infection. The inducible miR-146a could suppress the inducible nitric oxide (NO) synthase (iNOS) expression and NO generation, thus promoting mycobacterial survival in macrophages. Inhibition of endogenous miR-146a increased NO production and mycobacterial clearance. Moreover, miR-146a attenuated the activation of nuclear factor κB and mitogen-activated protein kinases signaling pathways during BCG infection, which in turn repressed iNOS expression. Mechanistically, miR-146a directly targeted tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) at post-transcriptional level. Silencing TRAF6 decreased iNOS expression and NO production in BCG-infected macrophages, while overexpression of TRAF6 reversed miR-146a-mediated inhibition of NO production and clearance of mycobacteria. Therefore, we demonstrated a novel role of miR-146a in the modulation of host defense against mycobacterial infection by repressing NO production via targeting TRAF6, which may provide a promising therapeutic target for tuberculosis.
Ghrelin Regulates Glucose and Glutamate Transporters in Hypothalamic Astrocytes
Authors: Fuente-Martín Esther , García-Cáceres Cristina , Argente-Arizón Pilar , Díaz Francisca , Granado Miriam , Freire-Regatillo Alejandra , Castro-González David , Ceballos María L. , Frago Laura M. , Dickson Suzanne L. , Argente Jesús , Chowen Julie A.
Published: March 2016

Hypothalamic astrocytes can respond to metabolic signals, such as leptin and insulin, to modulate adjacent neuronal circuits and systemic metabolism. Ghrelin regulates appetite, adiposity and glucose metabolism, but little is known regarding the response of astrocytes to this orexigenic hormone. We have used bothin vivoandin vitroapproaches to demonstrate that acylated ghrelin (acyl-ghrelin) rapidly stimulates glutamate transporter expression and glutamate uptake by astrocytes. Moreover, acyl-ghrelin rapidly reduces glucose transporter (GLUT) 2 levels and glucose uptake by these glial cells. Glutamine synthetase and lactate dehydrogenase decrease, while glycogen phosphorylase and lactate transporters increase in response to acyl-ghrelin, suggesting a change in glutamate and glucose metabolism, as well as glycogen storage by astrocytes. These effects are partially mediated through ghrelin receptor 1A (GHSR-1A) as astrocytes do not respond equally to desacyl-ghrelin, an isoform that does not activate GHSR-1A. Moreover, primary astrocyte cultures from GHSR-1A knock-out mice do not change glutamate transporter or GLUT2 levels in response to acyl-ghrelin. Our results indicate that acyl-ghrelin may mediate part of its metabolic actions through modulation of hypothalamic astrocytes and that this effect could involve astrocyte mediated changes in local glucose and glutamate metabolism that alter the signals/nutrients reaching neighboring neurons.
Retargeting the Clostridium botulinum C2 toxin to the neuronal cytosol
Authors: Pavlik Benjamin J. , Hruska Elizabeth J. , Van Cott Kevin E. , Blum Paul H.
Published: March 2016

Many biological toxins are known to attack specific cell types, delivering their enzymatic payloads to the cytosol. This process can be manipulated by molecular engineering of chimeric toxins. Using toxins with naturally unlinked components as a starting point is advantageous because it allows for the development of payloads separately from the binding/translocation components. Here the Clostridium botulinum C2 binding/translocation domain was retargeted to neural cell populations by deleting its non-specific binding domain and replacing it with a C. botulinum neurotoxin binding domain. This fusion protein was used to deliver fluorescently labeled payloads to Neuro-2a cells. Intracellular delivery was quantified by flow cytometry and found to be dependent on artificial enrichment of cells with the polysialoganglioside receptor GT1b. Visualization by confocal microscopy showed a dissociation of payloads from the early endosome indicating translocation of the chimeric toxin. The natural Clostridium botulinum C2 toxin was then delivered to human glioblastoma A172 and synchronized HeLa cells. In the presence of the fusion protein, native cytosolic enzymatic activity of the enzyme was observed and found to be GT1b-dependent. This retargeted toxin may enable delivery of therapeutics to peripheral neurons and be of use in addressing experimental questions about neural physiology.
Optogenetically controlled RAF to characterize BRAF and CRAF protein kinase inhibitors
Authors: Chatelle Claire V. , Hövermann Désirée , Müller Anne , Wagner Hanna J. , Weber Wilfried , Radziwill Gerald
Published: March 2016

Here, we applied optoRAF, an optogenetic tool for light-controlled clustering and activation of RAF proteins that mimics the natural occurring RAS-mediated dimerization. This versatile tool allows studying the effect on BRAF and CRAF homodimer- as well as heterodimer-induced RAF signaling. Vemurafenib and dabrafenib are two clinically approved inhibitors for BRAF that efficiently suppress the kinase activity of oncogenic BRAF (V600E). However in wild-type BRAF expressing cells, BRAF inhibitors can exert paradoxical activation of wild-type CRAF. Using optoRAF, vemurafenib was identified as paradoxical activator of BRAF and CRAF homo- and heterodimers. Dabrafenib enhanced activity of light-stimulated CRAF at low dose and inhibited CRAF signaling at high dose. Moreover, dabrafenib increased the protein level of CRAF proteins but not of BRAF proteins. Increased CRAF levels correlate with elevated RAF signaling in a dabrafenib-dependent manner, independent of light activation.
Soluble alpha-enolase activates monocytes by CD14-dependent TLR4 signalling pathway and exhibits a dual function
Authors: Guillou Clément , Fréret Manuel , Fondard Emeline , Derambure Céline , Avenel Gilles , Golinski Marie-Laure , Verdet Mathieu , Boyer Olivier , Caillot Frédérique , Musette Philippe , Lequerré Thierry , Vittecoq Olivier
Published: March 2016

Rheumatoid arthritis (RA) is the most common form of chronic inflammatory rheumatism. Identifying auto-antigens targeted by RA auto-antibodies is of major interest. Alpha-enolase (ENO1) is considered to be a pivotal auto-antigen in early RA but its pathophysiologic role remains unknown. The main objective of this study was to investigate the in vitro effects of soluble ENO1 on peripheral blood mononuclear cells (PBMC) from healthy donors and RA patients in order to determine the potential pathogenic role of ENO1. ELISA, transcriptomic analysis, experiments of receptor inhibition and flow cytometry analysis were performed to determine the effect, the target cell population and the receptor of ENO1. We showed that ENO1 has the ability to induce early production of pro-inflammatory cytokines and chemokines with delayed production of IL-10 and to activate the innate immune system. We demonstrated that ENO1 binds mainly to monocytes and activates the CD14-dependent TLR4 pathway both in healthy subjects and in RA patients. Our results establish for the first time that ENO1 is able to activate in vitro the CD14-dependent TLR4 pathway on monocytes involving a dual mechanism firstly pro-inflammatory and secondly anti-inflammatory. These results contribute to elucidating the role of this auto-antigen in the pathophysiologic mechanisms of RA.
A snap shot of the short-term response of crustaceans to macrophyte detritus in the deep Oslofjord
Authors: Ramirez-Llodra Eva , Rinde Eli , Gundersen Hege , Christie Hartvig , Fagerli Camilla With , Fredriksen Stein , Gitmark Janne Kim , Norling Karl , Walday Mats Gunnar , Norderhaug Kjell Magnus
Published: March 2016

A test deployment of a time-lapse camera lander in the deep Oslofjord (431 m) was used to obtain initial information on the response of benthic fauna to macroalgal debris. Three macroalgal species were used on the lander baited plate: Fucus serratus, Saccharina latissima and Laminaria hyperborea and observed during 41.5 hours. The deep-water shrimp Pandalus borealis were attracted to the macroalgae rapidly (3 min after the lander reached the seafloor), followed by amphipods. Shrimp abundances were significantly higher in areas covered by macroalgae compared to the adjacent seafloor and the number of shrimp visiting the macroalgae increased with time. Amphipods arrived 13 hours later and were observed mainly on decaying L. hyperborea. The abundance of amphipods on L. hyperborea increased rapidly, reaching a peak at 31 h after deployment. These initial observations suggest that debris from kelp forests and other macroalgal beds may play an important role in fuelling deep benthic communities in the outer Oslofjord and, potentially, enhance secondary production of commercial species such as P. borealis.
A chemical family-based strategy for uncovering hidden bioactive molecules and multicomponent interactions in herbal medicines
Authors: Song Hui-Peng , Wu Si-Qi , Hao Haiping , Chen Jun , Lu Jun , Xu Xiaojun , Li Ping , Yang Hua
Published: March 2016

Two concepts involving natural products were proposed and demonstrated in this paper. (1) Natural product libraries (e.g. herbal extract) are not perfect for bioactivity screening because of the vast complexity of compound compositions, and thus a library reconstruction procedure is necessary before screening. (2) The traditional mode of “screening single compound” could be improved to “screening single compound, drug combination and multicomponent interaction” due to the fact that herbal medicines work by integrative effects of multi-components rather than single effective constituents. Based on the two concepts, we established a novel strategy aiming to make screening easier and deeper. Using thrombin as the model enzyme, we firstly uncovered the minor lead compounds, potential drug combinations and multicomponent interactions in an herbal medicine of Dan-Qi pair, showing a significant advantage over previous methods. This strategy was expected to be a new and promising mode for investigation of herbal medicines.
Transcriptional profiling analysis of Spodoptera litura larvae challenged with Vip3Aa toxin and possible involvement of trypsin in the toxin activation
Authors: Song Feifei , Chen Chen , Wu Songqing , Shao Ensi , Li Mengnan , Guan Xiong , Huang Zhipeng
Published: March 2016

Vip proteins, a new group of insecticidal toxins produced byBacillus thuringiensis, are effective against specific pests includingSpodoptera litura. Here, we report construction of a transcriptome database ofS. liturabyde novoassembly along with detection of the transcriptional response ofS. lituralarvae to Vip3Aa toxin. In total, 56,498 unigenes with an N50 value of 1,853 bp were obtained. Results of transcriptome abundance showed that Vip3Aa toxin provoked a wide transcriptional response of theS. lituramidgut. The differentially expressed genes were enriched for immunity-related, metabolic-related and Bt-related genes. Twenty-nine immunity-related genes, 102 metabolic-related genes and 62 Bt-related genes with differential expression were found. On the basis of transcriptional profiling analysis, we focus on the functional validation of trypsin which potentially participated in the activation of Vip3Aa protoxin. Zymogram analysis indicated that the presence of many proteases, including trypsin, inS. lituralarvae midgut. Results of enzymolysisin vitroof Vip3Aa by trypsin and bioassay and histopathology of the trypsin-digested Vip3Aa toxin showed that trypsin was possibly involved in the Vip3Aa activation. This study provides a transcriptome foundation for the identification and functional validation of the differentially expressed genes in an agricultural important pest,S. litura.
Erratum: Adipose tissue fatty acid chain length and mono-unsaturation increases with obesity and insulin resistance
Authors: Tan Chong Yew , Virtue Samuel , Murfitt Steven , Roberts Lee D. , Phua Yi Hui , Dale Martin , Griffin Julian L. , Tinahones Francisco , Scherer Philipp E. , Vidal-Puig Antonio
Published: March 2016

Scientific Reports 5: Article number: 18366; published online: 17 December 2015; updated: 30 March 2016 The original version of this Article contained a typographical error in the spelling of the author Lee D. Roberts, which was incorrectly given as Lee D. Robert. This has now been corrected in the PDF and HTML versions of the Article.
Adenosine receptor agonist NECA increases cerebral extravasation of fluorescein and low molecular weight dextran independent of blood-brain barrier modulation
Authors: Cheng Chih-Chung , Yang Ya Lan , Liao Kate Hsiurong , Lai Ted Weita
Published: March 2016

Conventional methods for therapeutic blood-brain barrier (BBB) disruption facilitate drug delivery but are cumbersome to perform. A previous study demonstrated that adenosine receptor (AR) stimulation by 5′-N-ethylcarboxamide adenosine (NECA) increased the extravasation of intravascular tracers into the brain and proposed that AR agonism may be an effective method for therapeutic BBB disruption. We attempted to confirm the extravasation of tracers into the brain and also investigated tracer extravasation into peripheral organs and tracer retention in the blood. We found that NECA not only increased the extravasation of intravascular fluorescein and low molecular weight dextran into the brain of mice but also increased the concentrations of these tracers in the blood. In fact, the brain:blood ratio-normalized BBB permeability for either tracer is actually decreased by NECA administration. Elevated blood urea nitrogen levels in mice following NECA treatment suggested that renal function impairment was a probable cause of tracer retention. Therefore, NECA has almost no effect on the extravasation of intravascular Evans blue dye (EBD), an albumin-binding tracer with little renal clearance. Rather than inducing BBB disruption, our study demonstrated that NECA increased tracer extravasation into the brain by increasing the concentration gradient of the tracer across the BBB.
Fabrication of a miniaturized capillary waveguide integrated fiber-optic sensor for fluoride determination
Authors: Xiong Yan , Wang Chengjie , Tao Tao , Duan Ming , Tan Jun , Wu Jiayi , Wang Dong
Published: March 2016

Fluoride concentration is a key aspect of water quality and essential for human health.
Fluorescence behaviour of an anthracene–BODIPY system affected by spin states of a dioxolene–cobalt centre
Authors: Katayama Koichi , Hirotsu Masakazu , Ito Akitaka , Teki Yoshio
Published: March 2016

Fluorescence of an anthracene–BODIPY unit incorporated in a dioxolene ligand was effectively quenched in the low-spin cobalt(iii) catecholate complex compared with that in the high-spin cobalt(ii) semiquinonate complex.
A tandem dye-sensitized photoelectrochemical cell for light driven hydrogen production
Authors: Sherman Benjamin D. , Bergkamp Jesse J. , Brown Chelsea L. , Moore Ana L. , Gust Devens , Moore Thomas A.
Published: March 2016

A tandem cell incorporating two dye-sensitized photoanodes produces H2 from hydroquinone using only light energy and no applied electrical bias.
Oblique rotation of factors: a novel pattern recognition strategy to classify fluorescence excitation–emission matrices of human blood plasma for early diagnosis of colorectal cancer
Authors: Shahbazy Mohammad , Vasighi Mahdi , Kompany-Zareh Mohsen , Ballabio Davide
Published: March 2016

Oblique rotation of factors would be advantageous for improvement of classification models in challenging biochemical and omics systems.
Host–guest strategy to potently camouflage and restore the activity and toxicity of drugs affecting bacterial growth and viability
Authors: Gravel J. , Elie C. R. , Khayat M. , Schmitzer A.
Published: March 2016

We demonstrate the application of a controllable drug delivery system, where an active and toxic imidazolium salt can be camouflaged when assembled as an inclusion complex with cyclodextrins.
The evolution of drug discovery: from phenotypes to targets, and back
Authors: Al-Ali Hassan
Published: March 2016

Cumulative scientific and technological advances over the past two centuries have transformed drug discovery from a largely serendipitous process into the high tech pipelines of today.
Verification of redox-processes as switching and retention failure mechanisms in Nb:SrTiO3/metal devices
Authors: Baeumer C. , Raab N. , Menke T. , Schmitz C. , Rosezin R. , Müller P. , Andrä M. , Feyer V. , Bruchhaus R. , Gunkel F. , Schneider C. M. , Waser R. , Dittmann R.
Published: March 2016

We demonstrate that nanoscale redox reactions rather than purely electronic effects are responsible for resistive switching in Pt/Nb:SrTiO3 junctions.
The different effect of reduced graphene oxide and graphene oxide on the performance of chitosan by using homogenous fillers
Authors: Zhou Tiannan , Qi Xiaodong , Bai Hongwei , Fu Qiang
Published: March 2016

The different mechanism of the improved mechanical properties of CS–GO and CS–rGO nanocomposites are strong interfacial interaction and recrystallization, respectively.
Investigation on the growth, structural, HOMO–LUMO and optical studies of 1-ethyl-2-[2-(4-hydroxy-phenyl)-vinyl]-pyridinium iodide (HSPI) – a new stilbazolium derivative for third-order NLO applications
Authors: Nivetha K. , Kalainathan S. , Yamada Manabu , Kondo Yoshihiko , Hamada Fumio
Published: March 2016

The organic third-order non-linear optical crystal HSPI, a new derivative of the stilbazolium family, was successfully synthesized and the optical quality single crystal was grown by a slow evaporation technique for the first time.
A ratiometric fluorescence probe for detection of hydrogen sulfide in cells
Authors: Wang Bin , Jiang Na , Sun Wei , Wang Qiufen , Zheng Gengxiu
Published: March 2016

A near-infrared ratiometric fluorescence probe, BOC, was developed for detection of H2S. The probe features high selectivity and sensitivity. And BOC has the ability to detect H2S in living cells.
Near-infrared luminescence and SMM behaviors of a family of dinuclear lanthanide 8-quinolinolate complexes
Authors: Shen Hai-Yun , Wang Wen-Min , Gao Hong-Ling , Cui Jian-Zhong
Published: March 2016

Herein we report the near-infrared luminescence properties and SMM behaviors of five new lanthanide complexes based on 8-hydroxyquinoline and dibenzoylmethanate ligands.
Eu2+ → Tb3+ → Eu3+ energy transfer in Ca6La2Na2(PO4)6F2:Eu, Tb phosphors
Authors: Xie Mubiao , Zhu Guoxian , Li Dongyu , Pan Rongkai , Fu Xionghui
Published: March 2016

Eu2+ → Tb3+ → Eu3+ energy transfer exist in CLPF host, and tunable emission with a large color gamut can be obtained under n-UV light excitation.
Room temperature photo-induced deposition of platinum mirrors and nano-layers from simple Pt(ii) precursor complexes in water–methanol solutions
Authors: Xian Liang , Engelbrecht Leon , Barkhuysen Shani , Koch Klaus R.
Published: March 2016

Mirror-like nano-layers of variable thicknesses can be deposited directly onto FTO glass at room temperature under continuous irradiation with polychromatic light from water/methanol solutions containing low concentrations of [PtCl4]2−.
A diarylethene-based fluorescent chemosensor for the sequential recognition of Fe3+ and cysteine
Authors: Liao Guanming , Zheng Chunhong , Xue Dandan , Fan Congbin , Liu Gang , Pu Shouzhi
Published: March 2016

A new fluorescent chemosensor based on a diarylethene was designed and synthesized for sequential recognition of Fe3+ and cysteine.
Silk fibroin scaffolds with a micro-/nano-fibrous architecture for dermal regeneration
Authors: Li Xiufang , You Renchuan , Luo Zuwei , Chen Guo , Li Mingzhong
Published: March 2016

A novel silk fibroin scaffold containing micro-/nano-fibers promoted dermal regeneration by providing 3D topographic cues.
3D-printed bioceramic scaffolds with a Fe3O4/graphene oxide nanocomposite interface for hyperthermia therapy of bone tumor cells
Authors: Zhang Yongliang , Zhai Dong , Xu Mengchi , Yao Qingqiang , Chang Jiang , Wu Chengtie
Published: March 2016

Magnetic scaffolds display prominent magnetothermal ability, and can effectively kill tumor cells in an alternating magnetic field and improve bone formation ability in vitro.
Morphology control and characteristics of ZnO/ZnS nanorod arrays synthesised by microwave‐assisted heating
Authors: Tsai Ming‐Kwen , Huang Wei , Hu Sheng‐Yao , Lee Jyh‐Wei , Lee Yueh‐Chien , Lee Min‐Hung , Shen Ji‐Lin
Published: March 2016

The morphology control investigations on ZnO/ZnS core/shell nanorod fabricated by microwave‐assisted in‐situ surface sulphidation of ZnO nanorod arrays is presented. First, the ZnO nanorod arrays are grown on ZnO/Si substrate by microwave heating of a mixed zinc nitrate hexahydrate and hexamethylenetetramine precursors in deionised water. Then, the grown ZnO nanorod arrays on ZnO/Si substrate are immersed in thioacetamide (TAA) aqueous solution to undergo sulphidation process to form ZnS shell on ZnO core. The morphological, structural, and optical characteristics of the as‐prepared ZnO nanorods and ZnO/ZnS core/shell nanorods are investigated by scanning electron microscopy (SEM), X‐ray diffraction (XRD), and photoluminescence (PL) measurements, respectively. The SEM images and XRD patterns show that the ZnS shell becomes thicker due to more and more ZnS nanoparticles formed with increasing the concentration of TAA solution. The PL spectra demonstrate that the thicker ZnS shell results in more oxygen vacancies occupied by S atom, and would decrease the intensity ratio of the deep‐level emission to the ultra‐violet emission for the ZnO/ZnS core/shell nanorods synthesised with the higher concentration of TAA solution.
Photocatalytic performance of thermally prepared TiO2/C photocatalysts under artificial solar light
Authors: Wanag Agnieszka , Kusiak‐Nejman Ewelina , Kapica‐Kozar Joanna , Morawski Antoni Waldemar
Published: March 2016

A simple method of preparation of artificial solar light‐active TiO2 photocatalysts is presented. The new TiO2/C samples were obtained by thermal treatment (150, 250, 350 and 450 °C) of industrial titanium dioxide (TiO2‐starting) in the presence of naphthalene vapours. The obtained nanomaterials were investigated by means of UV‐vis/DR, Fourier transform infrared spectroscopy/diffuse reflectance infrared and X‐ray powder diffraction methods. Brunauer–Emmett–Teller (BET) specific surface area and carbon content were also measured. The photocatalytic activity of the photocatalysts was investigated on the basis of phenol degradation under artificial solar light. TiO2/C photocatalysts show higher photocatalytic activity in comparison with TiO2‐starting and commercial KRONOClean 7000 photocatalysts. It was noted that the highest decomposition and mineralisation degree of phenol and its degradation co‐products were found for sample obtained at 450 °C and contained 0.19 wt.% of carbon. The carbon content, BET surface area and anatase crystallite size are the mean features, which strongly contribute the photocatalytic activity of new carbon‐modified TiO2 photocatalysts under artificial solar light. Modification of TiO2 with naphthalene vapours is a promising method, especially taking the mineralisation of phenol and the co‐products of its degradation into account.
Development of a compact vertical-cavity surface-emitting laser end-pumped actively Q-switched laser for laser-induced breakdown spectroscopy
Authors: Li Shuo , Liu Lei , Chen Rongzhang , Nelsen Bryan , Huang Xi , Lu Yongfeng , Chen Kevin
Published: March 2016

This paper reports the development of a compact and portable actively Q-switched Nd:YAG laser and its applications in laser-induced breakdown spectroscopy (LIBS). The laser was end-pumped by a vertical-cavity surface-emitting laser (VCSEL). The cavity lases at a wavelength of 1064 nm and produced pulses of 16 ns with a maximum pulse energy of 12.9 mJ. The laser exhibits a reliable performance in terms of pulse-to-pulse stability and timing jitter. The LIBS experiments were carried out using this laser on NIST standard alloy samples. Shot-to-shot LIBS signal stability, crater profile, time evolution of emission spectra, plasma electron density and temperature, and limits of detection were studied and reported in this paper. The test results demonstrate that the VCSEL-pumped solid-state laser is an effective and compact laser tool for laser remote sensing applications.
Apparatus for generating quasi-free-space microwave-driven plasmas
Authors: Hoff Brad W. , French David M. , Reid Remington R. , Lawrance Julie E. , Lepell P. David , Maestas Sabrina S.
Published: March 2016

An apparatus for generating quasi-free-space microwave-driven plasmas has been designed, constructed, and tested. The plasma is driven by a multi-kW, ∼5 GHz microwave beam focused at the center of a vacuum chamber using a Koch-type metal plate lens. Sustained plasma discharges have been generated in argon at pressures ranging from 150 to 200 mTorr, at beam power levels ranging from 5 to 10 kW, and at gas flow rates of approximately 200 SCCM.
Access to residual carrier concentration in ZnO nanowires by calibrated scanning spreading resistance microscopy
Authors: Wang L. , Chauveau J. M. , Brenier R. , Sallet V. , Jomard F. , Sartel C. , Brémond G.
Published: March 2016

Scanning spreading resistance microscopy (SSRM) was performed on non-intentionally doped (nid) ZnO nanowires (NWs) grown by metal-organic chemical vapor deposition in order to measure their residual carrier concentration. For this purpose, an SSRM calibration profile has been developed on homoepitaxial ZnO:Ga multilayer staircase structures grown by molecular beam epitaxy. The Ga density measured by SIMS varies in the 1.7 × 1017 cm−3 to 3 × 1020 cm−3 range. From measurements on such Ga doped multi-layers, a monotonic decrease in SSRM resistance with increasing Ga density was established, indicating SSRM being a well-adapted technique for two dimensional dopant/carrier profiling on ZnO at nanoscale. Finally, relevant SSRM signal contrasts were detected on nid ZnO NWs, and the residual carrier concentration is estimated in the 1–3 × 1018 cm−3 range, in agreement with the result from four-probe measurements.
A charge inverter for III-nitride light-emitting diodes
Authors: Zhang Zi-Hui , Zhang Yonghui , Bi Wengang , Geng Chong , Xu Shu , Demir Hilmi Volkan , Sun Xiao Wei
Published: March 2016

In this work, we propose a charge inverter that substantially increases the hole injection efficiency for InGaN/GaN light-emitting diodes (LEDs). The charge inverter consists of a metal/electrode, an insulator, and a semiconductor, making an Electrode-Insulator-Semiconductor (EIS) structure, which is formed by depositing an extremely thin SiO2 insulator layer on the p+-GaN surface of a LED structure before growing the p-electrode. When the LED is forward-biased, a weak inversion layer can be obtained at the interface between the p+-GaN and SiO2 insulator. The weak inversion region can shorten the carrier tunnel distance. Meanwhile, the smaller dielectric constant of the thin SiO2 layer increases the local electric field within the tunnel region, and this is effective in promoting the hole transport from the p-electrode into the p+-GaN layer. Due to the improved hole injection, the external quantum efficiency is increased by 20% at 20 mA for the 350 × 350 μm2 LED chip. Thus, the proposed EIS holds great promise for high efficiency LEDs.
Experimental implementation of a nonlinear beamsplitter based on a phase-sensitive parametric amplifier
Authors: Fang Yami , Feng Jingliang , Cao Leiming , Wang Yaxian , Jing Jietai
Published: March 2016

Beamsplitters have played an important role in quantum optics experiments. They are often used to split and combine two beams, especially in the construct of an interferometer. In this letter, we experimentally implement a nonlinear beamsplitter using a phase-sensitive parametric amplifier, which is based on four-wave mixing in hot rubidium vapor. Here we show that, despite the different frequencies of the two input beams, the output ports of the nonlinear beamsplitter exhibit interference phenomena. We make measurements of the interference fringe visibility and study how various parameters, such as the intensity gain of the amplifier, the intensity ratio of the two input beams, and the one and two photon detunings, affect the behavior of the nonlinear beamsplitter. It may find potential applications in quantum metrology and quantum information processing.
Temperature-dependent capacitance–voltage and current–voltage characteristics of Pt/Ga2O3 (001) Schottky barrier diodes fabricated on n––Ga2O3 drift layers grown by halide vapor phase epitaxy
Authors: Higashiwaki Masataka , Konishi Keita , Sasaki Kohei , Goto Ken , Nomura Kazushiro , Thieu Quang Tu , Togashi Rie , Murakami Hisashi , Kumagai Yoshinao , Monemar Bo , Koukitu Akinori , Kuramata Akito , Yamakoshi Shigenobu
Published: March 2016

We investigated the temperature-dependent electrical properties of Pt/Ga2O3 Schottky barrier diodes (SBDs) fabricated on n–-Ga2O3 drift layers grown on single-crystal n+-Ga2O3 (001) substrates by halide vapor phase epitaxy. In an operating temperature range from 21 °C to 200 °C, the Pt/Ga2O3 (001) Schottky contact exhibited a zero-bias barrier height of 1.09–1.15 eV with a constant near-unity ideality factor. The current–voltage characteristics of the SBDs were well-modeled by thermionic emission in the forward regime and thermionic field emission in the reverse regime over the entire temperature range.
Laser induced sonofusion: A new road toward thermonuclear reactions
Authors: Sadighi-Bonabi Rasoul , Gheshlaghi Maryam
Published: March 2016

The Possibility of the laser assisted sonofusion is studied via single bubble sonoluminescence (SBSL) in Deuterated acetone (C3D6O) using quasi-adiabatic and hydro-chemical simulations at the ambient temperatures of 0 and −28.5 °C. The interior temperature of the produced bubbles in Deuterated acetone is 1.6 × 106 K in hydro-chemical model and it is reached up to 1.9 × 106 K in the laser induced SBSL bubbles. Under these circumstances, temperature up to 107 K can be produced in the center of the bubble in which the thermonuclear D-D fusion reactions are promising under the controlled conditions.
Mixed convective thermally radiative micro nanofluid flow in a stretchable channel with porous medium and magnetic field
Authors: Rauf A. , Shahzad S. A. , Siddiq M. K. , Raza J. , Meraj M. A.
Published: March 2016

A numerical study is carried out for two dimensional steady incompressible mixed convective flow of electrically conductive micro nanofluid in a stretchable channel. The flow is generated due to the stretching walls of the channel immersed in a porous medium. The magnetic field is applied perpendicular to the walls. The impact of radiation, viscous dissipation, thermophoretic and Brownian motion of nanoparticles appear in the energy equation. A numerical technique based on Runge-Kutta-Fehlberg fourth-fifth order (RFK45) method is used to express the solutions of velocity, microrotation, temperature and concentration fields. The dimensionless physical parameters are discussed both in tabular and graphical forms. The results are also found in a good agreement with previously published literature work.
Reporter nanoparticle that monitors its anticancer efficacy in real time
Authors: Kulkarni Ashish , Rao Poornima , Natarajan Siva , Goldman Aaron , Sabbisetti Venkata S. , Khater Yashika , Korimerla Navya , Chandrasekar Vineethkrishna , Mashelkar Raghunath A. , Sengupta Shiladitya
Published: March 2016

Significance

The ability to identify responders and nonresponders very early during chemotherapy by direct visualization of the activity of the anticancer treatment and to switch, if necessary, to a regimen that is effective can have a significant effect on the outcome as well as quality of life. Current approaches to quantify response rely on imaging techniques that fail to detect very early responses. In the case of immunotherapy, the early anatomical readout is often discordant with the biological response. This study describes a self-reporting nanomedicine that not only delivers chemotherapy or immunotherapy to the tumor but also reports back on its efficacy in real time, thereby identifying responders and nonresponders early on.
Finite order solutions of difference equations, and difference Painlevé equations IV
Authors: Wen Zhi-Tao
Published: March 2016

In this paper, from the non-linear difference equation
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="left-parenthesis w overbar plus w right-parenthesis left-parenthesis w plus w underbar right-parenthesis equals StartFraction upper P left-parenthesis z comma w right-parenthesis Over upper Q left-parenthesis z comma w right-parenthesis EndFraction">

(

w
¯

+
w
)
(
w
+

w
_

)
=

P
(
z
,
w
)

Q
(
z
,
w
)

(\overline {w}+w)(w+\underline {w})=\frac {P(z,w)}{Q(z,w)}

\]
where

P
(
z
,
w
)

P(z,w)

and

Q
(
r
,
w
)

Q(r,w)

are polynomials in

w
(
z
)

w(z)

without common factors having small function coefficients related to

w
(
z
)

w(z)

, we present the form of difference Painlevé equation IV
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="left-parenthesis w overbar plus w right-parenthesis left-parenthesis w plus w underbar right-parenthesis equals StartFraction left-parenthesis w squared minus a squared right-parenthesis left-parenthesis w squared minus b squared right-parenthesis Over left-parenthesis w plus left-parenthesis alpha z plus beta right-parenthesis right-parenthesis squared plus pi EndFraction comma">

(

w
¯

+
w
)
(
w
+

w
_

)
=

(

w
2

−

a
2

)
(

w
2

−

b
2

)

(
w
+
(
α
z
+
β
)

)
2

+
π

,

(\overline {w}+w)(w+\underline {w})=\frac {(w^2-a^2)(w^2-b^2)}{(w+(\alpha z+\beta ))^2+\pi },

\]
where

a
a

,

b
b

,

α
\alpha

,

β
\beta

and

π
\pi

are period small functions related to

w
w

. It shows that if the above difference equation admits at least one meromorphic solution

w
(
z
)

w(z)

of finite order, then the difference equation can be transformed by Möbius tranformation in

w
w

to difference Painlevé IV, unless

w
w

is the solution of difference Riccati equations.
The head and tail of the colored Jones polynomial for adequate knots
Authors: Armond Cody , Dasbach Oliver
Published: March 2016

We show that the head and tail functions of the colored Jones polynomial of adequate links are the product of head and tail functions of the colored Jones polynomial of alternating links that can be read-off an adequate diagram of the link. We apply this to strengthen a theorem of Kalfagianni, Futer and Purcell on the fiberedness of adequate links.
A Novel, Spatiotemporally Explicit Ecological‐economic Modeling Procedure for the Design of Cost‐effective Agri‐environment Schemes to Conserve Biodiversity
Authors: Wätzold Frank , Drechsler Martin , Johst Karin , Mewes Melanie , Sturm Astrid
Published: March 2016

Agri‐environment schemes (AES) compensate farmers for land use measures that are costly to them but beneficial to biodiversity and the environment. We present an ecological‐economic modeling procedure for the design of cost‐effective AES to conserve grassland biodiversity, which is applicable to large areas, covers many endangered species and grassland types, and includes several hundred different types of mowing regimes, grazing regimes, and combinations of mowing and grazing regimes as land use measures. The modeling procedure also accounts for the spatial variations in the land use measures' costs and in the effects on species and grassland types. The procedure's main novelty is that it considers variations of the costs and impacts on species and grassland types that arise from different timings of the land use measures. Considering the spatial and the temporal dimension of land use measures makes the modeling procedure spatiotemporally explicit. We demonstrate the power of the modeling procedure by evaluating an existing grassland AES in Saxony, Germany, and identify substantial improvements in terms of cost‐effectiveness.
Multidimensional Responses to Disease Information: How Do Winegrape Growers React to Powdery Mildew Forecasts and To What Environmental Effect?
Authors: Lybbert Travis J. , Magnan Nicholas , Gubler W. Douglas
Published: March 2016

Access to better information can enable adjustments that improve individual and social outcomes. In agriculture, accurate forecasts can be especially valuable to both producers and society at large. We analyze the impact of disease forecasts on the responses of growers along multiple margins of adjustment. Using high‐resolution plot‐level panel data, we analyze how California winegrape growers adjust powdery mildew control strategies in response to disease forecasts. While trials that allow only treatment timing adjustments suggest these forecasts bring large environmental benefits, in practice many growers simultaneously adjust what, when, and how much they spray. We find that the net environmental impact of this multidimensional response may actually be negative.
Connectivity of larval cod in the transition area between North Sea and Baltic Sea and potential implications for fisheries management
Authors: Huwer B. , Hinrichsen H.-H. , Hüssy K. , Eero M.
Published: March 2016

Connectivity of pelagic, early life stages via transport by ocean currents may affect survival chances of offspring, recruitment success, and mixing of stocks across management units. Based on drift model studies, transport patterns of particles representing exogenously feeding cod larvae in the transition area between North Sea and Baltic were investigated to (i) determine long-term trends and variability in advective transport of larvae from spawning grounds to juvenile nursery areas, (ii) estimate the degree of exchange between different management areas, and (iii) compare the results with spatial distributions of juvenile cod. The transport of particles showed considerable intra- and interannual variability, but also some general patterns of retention within and dispersion to different management areas. Good spatial overlap of particle end positions, representing potential juvenile settlement areas, with observed distributions of juveniles in bottom trawl surveys suggests that the drift simulations provide reasonable estimates of early life stage connectivity between cod populations in the investigated areas. High exchange rates of particles between management areas of up to ca. 70% suggest that cod populations in the investigated areas are demographically correlated. Results are discussed in relation to their relevance for stock structure, fish stock assessment, and management.
Simulating Counterfactual Representation
Authors: Eggers Andrew C. , Lauderdale Benjamin E.
Published: March 2016

We show how to use multilevel modeling and post-stratification to estimate legislative outcomes under counterfactual representation schemes that, for example, boost the representation of women or translate votes into seats differently. We apply this technique to two research questions: (1) Would the U.S. Congress be less polarized if state delegations were formed according to the principle of party proportional representation? (2) Would there have been stronger support for legalizing same-sex marriage in the U.K. House of Commons if Parliament more closely reflected the population in gender and age?
Palenque de San Basilio in Colombia: genetic data support an oral history of a paternal ancestry in Congo
Authors: Ansari-Pour Naser , Moñino Yves , Duque Constanza , Gallego Natalia , Bedoya Gabriel , Thomas Mark G. , Bradman Neil
Published: March 2016

The Palenque, a black community in rural Colombia, have an oral history of fugitive African slaves founding a free village near Cartagena in the seventeenth century. Recently, linguists have identified some 200 words in regular use that originate in a Kikongo language, with Yombe, mainly spoken in the Congo region, being the most likely source. The non-recombining portion of the Y chromosome (NRY) and mitochondrial DNA were analysed to establish whether there was greater similarity between present-day members of the Palenque and Yombe than between the Palenque and 42 other African groups (for all individuals,n= 2799) from which forced slaves might have been taken. NRY data are consistent with the linguistic evidence that Yombe is the most likely group from which the original male settlers of Palenque came. Mitochondrial DNA data suggested substantial maternal sub-Saharan African ancestry and a strong founder effect but did not associate Palenque with any particular African group. In addition, based on cultural data including inhabitants' claims of linguistic differences, it has been hypothesized that the two districts of the village (Abajo and Arriba) have different origins, with Arriba founded by men originating in Congo and Abajo by those born in Colombia. Although significant genetic structuring distinguished the two from each other, no supporting evidence for this hypothesis was found.
Predator encounters have spatially extensive impacts on parental behaviour in a breeding bird community
Authors: Moks Kadri , Tilgar Vallo , Thomson Robert L. , Calhim Sara , Järvistö Pauliina E. , Schuett Wiebke , Velmala William , Laaksonen Toni
Published: March 2016

Predation risk has negative indirect effects on prey fitness, partly mediated through changes in behaviour. Evidence that individuals gather social information from other members of the population suggests that events in a community may impact the behaviour of distant individuals. However, spatially wide-ranging impacts on individual behaviour caused by a predator encounter elsewhere in a community have not been documented before. We investigated the effect of a predator encounter (hawk model presented at a focal nest) on the parental behaviour of pied flycatchers (Ficedula hypoleuca), both at the focal nest and at nearby nests different distances from the predator encounter. We show that nest visitation of both focal pairs and nearby pairs were affected, up to 3 h and 1 h, respectively. Parents also appeared to compensate initial disrupted feeding by later increasing nest visitation rates. This is the first evidence showing that the behaviour of nearby pairs was affected away from an immediate source of risk. Our results indicate that the impacts of short-term predator encounters may immediately extend spatially to the broader community, affecting the behaviour of distant individuals. Information about predators is probably quickly spread by cues such as intra- and heterospecific alarm calls, in communities of different taxa.
Location-specific cuticular hydrocarbon signals in a social insect
Authors: Wang Qike , Goodger Jason Q. D. , Woodrow Ian E. , Elgar Mark A.
Published: March 2016

Social insects use cuticular hydrocarbons (CHCs) to convey different social signals, including colony or nest identity. Despite extensive investigations, the exact source and identity of CHCs that act as nest-specific identification signals remain largely unknown. Perhaps this is because studies that identify CHC signals typically use organic solvents to extract a single sample from the entire animal, thereby analysing a cocktail of chemicals that may serve several signal functions. We took a novel approach by first identifying CHC profiles from different body parts of ants (
Iridomyrmex purpureus
), then used behavioural bioassays to reveal the location of specific social signals. The CHC profiles of both workers and alates varied between different body parts, and workers paid more attention to the antennae of non-nest-mate and the legs of nest-mate workers. Workers responded less aggressively to non-nest-mate workers if the CHCs on the antennae of their opponents were removed with a solvent. These data indicate that CHCs located on the antennae reveal nest-mate identity and, remarkably, that antennae both convey and receive social signals. Our approach and findings could be valuably applied to chemical signalling in other behavioural contexts, and provide insights that were otherwise obscured by including chemicals that either have no signal function or may be used in other contexts.
BIGMAC: Breaking Inaccurate Genomes and Merging Assembled Contigs for long read metagenomic assembly
Authors: Lam Ka-Kit , Hall Richard , Clum Alicia , Rao Satish
Published: March 2016

The problem of de-novo assembly for metagenomes using only long reads is gaining attention. We study whether post-processing metagenomic assemblies with the original input long reads can result in quality improvement. Previous approaches have focused on pre-processing reads and optimizing assemblers. BIGMAC takes an alternative perspective to focus on the post-processing step. Using both the assembled contigs and original long reads as input, BIGMAC first breaks the contigs at potentially mis-assembled locations and subsequently scaffolds contigs. Our experiments on metagenomes assembled from long reads show that BIGMAC can improve assembly quality by reducing the number of mis-assemblies while maintaining/increasing N50 and N75. The software is available athttps://github.com/kakitone/BIGMAC