bluuebunny/crossref_metadata_2025 huggingface dataset:
Ambulo Ergo Sum
Authors: O'Brien Lucy
Published: July 2015

It is an extraordinary thing that Descartes' famous Cogito argument is still being puzzled over; this paper is another fragment in an untiring tradition of puzzlement. The paper will argue that, if I were to ask the question ‘do I have a grounds for thinking that I exist?’ the Cogito could provide for a positive answer. In particular, my aim in this is to argue, in opposition to recent discussion by John Campbell, that there is a way of construing conscious thinking on which the Cogito can be seen to provide a non-question begging argument for one's own existence.
On Parfit's View That We Are Not Human Beings
Authors: Olson Eric T.
Published: July 2015

Derek Parfit claims that we are not human beings. Rather, each of us is the part of a human being that thinks in the strictest sense. This is said to solve a number of difficult metaphysical problems. I argue that the view has metaphysical problems of its own, and is inconsistent with any psychological-continuity account of personal identity over time, including Parfit's own.
Power, Scepticism and Ethical Theory
Authors: Pink Thomas
Published: July 2015

It is often thought that as human agents we have a power to determine our actions for ourselves. And a natural conception of this power is as freedom – a power over alternatives so that we can determine for ourselves which of a variety of possible actions we perform. But what is the real content of this conception of freedom, and need self-determination take this particular form? I examine the possible forms self-determination might take, and the various ways freedom as a power over alternatives might be constituted. I argue that though ordinary ethical thought, and especially moral blame, may be committed to our possession of some capacity for self-determination, the precise nature of this power is probably ethically underdetermined – though conceptions of the nature of the power that come from outside ethics may then have important implications for ethics.
Effects and noneffects of input in bilingual environments on dual language skills in 2 ½-year-olds
Authors: PLACE SILVIA , HOFF ERIKA
Published: July 2015

Recent findings suggest some properties of input in dual-language environments that influence its value for bilingual development, but the extant data base is small and sometimes inconclusive. The present study sought additional evidence regarding three quality indicators: the percent of input provided by native speakers, the number of different speakers providing input, and the frequency of language mixing. Participants were 90 thirty-month-olds exposed to Spanish and English. Using the Language Diary method to assess input and using multiple measures of children's bilingual skills, results replicated previous findings that the percent of input provided by native speakers is a positive quality indicator and found suggestive evidence that the number of speakers is also a positive quality indicator. There was little evidence that the frequency of language mixing is a negative indicator. These findings advance understanding of sources of variability in bilingual outcomes and have implications for programs to support bilingual development.
Microscopy and Microanalysis of an Extreme Case of Salt and Biodegradation in 17th Century Wall Paintings
Authors: Gil Milene , Martins Maria Rosário , Carvalho Maria Luisa , Souto Cátia , Longelin Stephane , Cardoso Ana , Mirão José , Candeias António Estevão
Published: July 2015

The present study characterizes the main deterioration mechanisms affecting the early 17th frescoes ofCasa de Fresco, the only known example in Portugal of a semi-underground leisure room richly decorated with a balcony over a water well. Frescoes from the vault are at risk due to salt weathering and biodeterioration. The aim of the research was identification of the deterioration materials, determination of their origin, and their effect on the frescoes before future intervention. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was used to determine salt morphology and microanalysis. The mineralogical characterization was performed by X-ray powder diffraction, complemented withµ-Raman andµ-Fourier transform infrared spectroscopy. Biological assessment was evaluated with optical microscopy and SEM-EDS. Bacterial and fungal isolation and identification were performed using standard culture media and methods according toBergey’s Manual of Systematic Bacteriologyand from theCompendium of Soil Fungi. The results show that Ca and Ca-Mg carbonates from the paint renderings are the predominant salt species affecting the site. Bacterial strains from the generaBacillusandPseudomonasand fungal strains from theCladosporiumspp. andPenicilliumspp. were isolated in the salt formations, within and between the mortar layers. Azurite, malachite, and smalt paint layers are the most affected by the weathering conditions.
Transcription regulates HIF‐1α expression in CD4+ T cells
Authors: Bollinger Thomas , Bollinger Annalena , Gies Sydney , Feldhoff Lea , Solbach Werner , Rupp Jan
Published: July 2015

The transcription factor hypoxia inducible factor‐1α (HIF‐1α) mediates the metabolic adaptation of cells to hypoxia and T‐helper cell fate. However, HIF‐1α regulation in CD4+ T cells (T cells) remains elusive. Here we observed that depletion of oxygen (O2⩽2%) alone was not sufficient to induce HIF‐1α expression in T cells. However, when hypoxic T cells were stimulated, HIF‐1α was expressed and this was dependent on nuclear factor‐κB‐ and nuclear factor of activated T cell (NFAT)‐mediated transcriptional upregulation of Hif‐1α mRNA. HIF‐1α upregulation could be blocked by drugs inhibiting NF‐κB, NFAT or mammalian target of rapamycin precluding CD4+ T‐cell stimulation or translation in T cells, as well as by blocking transcription. CD3, CD28, phorbol‐12‐myristat‐13‐acetat (PMA) or ionomycin‐stimulated T cells did not express HIF‐1α under normoxic conditions. In conclusion, regulation of HIF‐1α expression in CD4+ T cells in hypoxia gravely relies on its transcriptional upregulation and subsequent enhanced protein stabilization.
Giant anisotropic magnetoresistance in a quantum anomalous Hall insulator
Authors: Kandala Abhinav , Richardella Anthony , Kempinger Susan , Liu Chao-Xing , Samarth Nitin
Published: July 2015

When a three-dimensional ferromagnetic topological insulator thin film is magnetized out-of-plane, conduction ideally occurs through dissipationless, one-dimensional (1D) chiral states that are characterized by a quantized, zero-field Hall conductance. The recent realization of this phenomenon, the quantum anomalous Hall effect, provides a conceptually new platform for studies of 1D transport, distinct from the traditionally studied quantum Hall effects that arise from Landau level formation. An important question arises in this context: how do these 1D edge states evolve as the magnetization is changed from out-of-plane to in-plane? We examine this question by studying the field-tilt-driven crossover from predominantly edge-state transport to diffusive transport in Crx(Bi,Sb)2−xTe3 thin films. This crossover manifests itself in a giant, electrically tunable anisotropic magnetoresistance that we explain by employing a Landauer–Büttiker formalism. Our methodology provides a powerful means of quantifying dissipative effects in temperature and chemical potential regimes far from perfect quantization.
Genomic modulators of gene expression in human neutrophils
Authors: Naranbhai Vivek , Fairfax Benjamin P. , Makino Seiko , Humburg Peter , Wong Daniel , Ng Esther , Hill Adrian V. S. , Knight Julian C.
Published: July 2015

Neutrophils form the most abundant leukocyte subset and are central to many disease processes. Technical challenges in transcriptomic profiling have prohibited genomic approaches to date. Here we map expression quantitative trait loci (eQTL) in peripheral blood CD16+ neutrophils from 101 healthy European adults. We identify cis-eQTL for 3281 neutrophil-expressed genes including many implicated in neutrophil function, with 450 of these not previously observed in myeloid or lymphoid cells. Paired comparison with monocyte eQTL demonstrates nuanced conditioning of genetic regulation of gene expression by cellular context, which relates to cell-type-specific DNA methylation and histone modifications. Neutrophil eQTL are markedly enriched for trait-associated variants particularly autoimmune, allergy and infectious disease. We further demonstrate how eQTL in PADI4 and NOD2 delineate risk variant function in rheumatoid arthritis, leprosy and Crohn’s disease. Taken together, these data help advance understanding of the genetics of gene expression, neutrophil biology and immune-related diseases.
Voxel-based morphometry predicts shifts in dendritic spine density and morphology with auditory fear conditioning
Authors: Keifer Jr O. P. , Hurt R. C. , Gutman D. A. , Keilholz S. D. , Gourley S. L. , Ressler K. J.
Published: July 2015

Neuroimaging has provided compelling data about the brain. Yet the underlying mechanisms of many neuroimaging techniques have not been elucidated. Here we report a voxel-based morphometry (VBM) study of Thy1-YFP mice following auditory fear conditioning complemented by confocal microscopy analysis of cortical thickness, neuronal morphometric features and nuclei size/density. Significant VBM results included the nuclei of the amygdala, the insula and the auditory cortex. There were no significant VBM changes in a control brain area. Focusing on the auditory cortex, confocal analysis showed that fear conditioning led to a significantly increased density of shorter and wider dendritic spines, while there were no spine differences in the control area. Of all the morphology metrics studied, the spine density was the only one to show significant correlation with the VBM signal. These data demonstrate that learning-induced structural changes detected by VBM may be partially explained by increases in dendritic spine density.
Two-dimensional magnetotransport in a black phosphorus naked quantum well
Authors: Tayari V. , Hemsworth N. , Fakih I. , Favron A. , Gaufrès E. , Gervais G. , Martel R. , Szkopek T.
Published: July 2015

Black phosphorus (bP) is the second known elemental allotrope with a layered crystal structure that can be mechanically exfoliated to atomic layer thickness. Unlike metallic graphite and semi-metallic graphene, bP is a semiconductor in both bulk and few-layer form. Here we fabricate bP-naked quantum wells in a back-gated field effect transistor geometry with bP thicknesses ranging from 6±1 nm to 47±1 nm. Using a polymer encapsulant, we suppress bP oxidation and observe field effect mobilities up to 900 cm2 V−1 s−1 and on/off current ratios exceeding 105. Shubnikov-de Haas oscillations observed in magnetic fields up to 35 T reveal a 2D hole gas with Schrödinger fermion character in a surface accumulation layer. Our work demonstrates that 2D electronic structure and 2D atomic structure are independent. 2D carrier confinement can be achieved without approaching atomic layer thickness, advantageous for materials that become increasingly reactive in the few-layer limit such as bP.
A unique biofilm in human deep mycoses: fungal amyloid is bound by host serum amyloid P component
Authors: Garcia-Sherman Melissa C , Lundberg Tracy , Sobonya Richard E , Lipke Peter N , Klotz Stephen A
Published: July 2015

Background/objectives:

We have demonstrated the presence of Candida cell surface amyloids that are important in aggregation of fungi and adherence to tissue. Fungal amyloid was present in invasive human candidal infections and host serum amyloid P component (SAP) bound to the fungal amyloid. SAP is a protease-resistant glycoprotein that binds avidly to amyloid and interferes with host defence, especially against bacterial pathogens for which neutrophils are important. In this study, we investigated whether biofilm of fungal amyloid and SAP was a feature of other disseminated fungal infections.

Methods:

Tissue specimens from 15 autopsies were systematically evaluated with multiple histochemical stains including thioflavin T and Congo red (dyes that stain amyloid), as well as antibody to SAP. We studied specimens with disseminated aspergillosis, mucormycosis and coccidioidomycosis. The structure of the lesions, host inflammatory cells and the presence of fungal amyloid and SAP were determined.

Results:

The structure of the lesions was characteristic in aspergillosis (‘starburst’) and mucormycosis (closely apposed bundles of hyphae). Host inflammatory cells were absent or few in number within these lesions. In Coccidioides lesions, host inflammation was sparse as well. Fungal amyloid was a prominent feature of all lesions along with abundant SAP bound to hyphae and spherules. Fungal amyloid and SAP perhaps contributed to persistence in caseous necrosis lesions. SAP also bound to Aspergillus and Mucorales amyloid in vitro.

Conclusions:

A biofilm including amyloid and SAP is present in invasive fungal infections. This biofilm may dampen host defence leading to the characteristic sparse inflammatory reaction found in these infections.
A versatile snap chip for high-density sub-nanoliter chip-to-chip reagent transfer
Authors: Li Huiyan , Munzar Jeffrey D. , Ng Andy , Juncker David
Published: July 2015

The coordinated delivery of minute amounts of different reagents is important for microfluidics and microarrays, but is dependent on advanced equipment such as microarrayers. Previously, we developed the snap chip for the direct transfer of reagents, thus realizing fluidic operations by only manipulating microscope slides. However, owing to the misalignment between arrays spotted on different slides, millimeter spacing was needed between spots and the array density was limited. In this work, we have developed a novel double transfer method and have transferred 625 spots cm−2, corresponding to >10000 spots for a standard microscope slide. A user-friendly snapping system was manufactured to make liquid handling straightforward. Misalignment, which for direct transfer ranged from 150–250 μm, was reduced to <40 μm for double transfer. The snap chip was used to quantify 50 proteins in 16 samples simultaneously, yielding limits of detection in the pg/mL range for 35 proteins. The versatility of the snap chip is illustrated with a 4-plex homogenous enzyme inhibition assay analyzing 128 conditions with precise timing. The versatility and high density of the snap chip with double transfer allows for the development of high throughput reagent transfer protocols compatible with a variety of applications.
Synthesis of diamond-like phase from graphite by ultrafast laser driven dynamical compression
Authors: Maia Francisco C. B. , Samad Ricardo E. , Bettini Jefferson , Freitas Raul O. , Vieira Junior Nilson D. , Souza-Neto Narcizo M.
Published: July 2015

Rapid variations of the environmental energy caused by ultrashort laser pulses have induced phase transitions in carbon allotropes, therefore bringing the promise of revealing new carbon phases. Here, by exposing polycrystalline graphite to 25 fs laser pulses at 4 J/cm2 fluence under standard air atmosphere, we demonstrated the synthesis of translucent micrometer-sized structures carrying diamond-like and onion-like carbon phases. Texturized domains of the diamond phase were also identified. Concerning different synthesized carbon forms, pulse superposition and singularities of the thermodynamical process, we pinpoint the synthesis mechanism by the laser-induced subsequent products energetically evolving to attain the diamond-like phase.
Strategy to enhance efficacy of doxorubicin in solid tumor cells by methyl-β-cyclodextrin: Involvement of p53 and Fas receptor ligand complex
Authors: Mohammad Naoshad , Vikram Singh Shivendra , Malvi Parmanand , Chaube Balkrishna , Athavale Dipti , Vanuopadath Muralidharan , Nair Sudarslal Sadasivan , Nair Bipin , Bhat Manoj Kumar
Published: July 2015

Doxorubicin (DOX) is one of the preferred drugs for treating breast and liver cancers. However, its clinical application is limited due to severe side effects and the accompanying drug resistance. In this context, we investigated the effect on therapeutic efficacy of DOX by cholesterol depleting agent methyl-β-cyclodextrin (MCD) and explored the involvement of p53. MCD sensitizes MCF-7 and Hepa1–6 cells to DOX, Combination of MCD and marginal dose of DOX reduces the cell viability and promoted apoptosis through induction of pro-apoptotic protein, Bax, activation of caspase-8 and caspase-7, down regulation of anti-apoptotic protein Bcl-2 and finally promoting PARP cleavage. Mechanistically, sensitization to DOX by MCD was due to the induction of FasR/FasL pathway through p53 activation. Furthermore, inhibition of p53 by pharmacological inhibitor pifithrin-α (PFT-α) or its specific siRNA attenuated p53 function and down-regulated FasR/FasL, thereby preventing cell death. Animal experiments were performed using C57BL/6J mouse isografted with Hepa1–6 cells. Tumor growth was retarded and survival increased in mice administered MCD together with DOX to as compared to either agent alone. Collectively, these results suggest that MCD enhances the sensitivity to DOX for which wild type p53 is an important determinant.
Incorporation of a GPI-anchored engineered cytokine as a molecular adjuvant enhances the immunogenicity of HIV VLPs
Authors: Feng Hao , Zhang Han , Deng Jiusheng , Wang Li , He Yuan , Wang Shelly , Seyedtabaei Roheila , Wang Qing , Liu Laiting , Galipeau Jacques , Compans Richard W. , Wang Bao-Zhong
Published: July 2015

HIV vaccines should elicit immune responses at both the mucosal portals of entry to block transmission and systemic compartments to clear disseminated viruses. Co-delivery of mucosal adjuvants has been shown to be essential to induce effective mucosal immunity by non-replicating vaccines. A novel cytokine, GIFT4, engineered by fusing GM-CSF and interleukin-4, was previously found to simulate B cell proliferation and effector function. Herein a membrane-anchored form of GIFT4 was constructed by fusing a glycolipid (GPI)-anchoring sequence and incorporated into Env-enriched HIV virus-like particles (VLPs) as a molecular adjuvant. Guinea pigs were immunized with the resulting HIV VLPs through an intramuscular priming-intranasal boosting immunization route. The GIFT4-containing VLPs induced higher levels of systemic antibody responses with significantly increased binding avidity and improved neutralizing breadth and potency to a panel of selected strains, as well as higher levels of IgG and IgA at several mucosal sites. Thus, the novel GPI-GIFT4-containging VLPs have the potential to be developed into a prophylactic HIV vaccine. Incorporation of GPI-anchored GIFT4 into VLPs as a molecular adjuvant represents a novel approach to increase their immunogenicity.
Who started first? Bird species visiting novel birdfeeders
Authors: Tryjanowski Piotr , Morelli Federico , Skórka Piotr , Goławski Artur , Indykiewicz Piotr , Pape Møller Anders , Mitrus Cezary , Wysocki Dariusz , Zduniak Piotr
Published: July 2015

Adapting to exploit new food sources may be essential, particularly in winter, when the impact of food limitation on survival of individuals is critical. One of the most important additional sources of food for birds in human settlements is birdfeeders. At a large spatial scale, we experimentally provided birdfeeders with four different kinds of food to analyze exploitation and use of a novel food supply provided by humans. Nine species started foraging at the new birdfeeders. The species that exploited the new feeders the fastest was the great tit. Use of novel food sources was faster in urban habitats and the presence of other feeders reduced the time until a new feeder was located. Urbanization may be associated with behavioural skills, technical innovations and neophilia resulting in faster discovery of new food sources. This process is accelerated by the experience of feeder use in the vicinity, with a strong modifying effect of the number of domestic cats.
Electrically induced ambipolar spin vanishments in carbon nanotubes
Authors: Matsumoto D. , Yanagi K. , Takenobu T. , Okada S. , Marumoto K.
Published: July 2015

Carbon nanotubes (CNTs) exhibit various excellent properties, such as ballistic transport. However, their electrically induced charge carriers and the relation between their spin states and the ballistic transport have not yet been microscopically investigated because of experimental difficulties. Here we show an electron spin resonance (ESR) study of semiconducting single-walled CNT thin films to investigate their spin states and electrically induced charge carriers using transistor structures under device operation. The field-induced ESR technique is suitable for microscopic investigation because it can directly observe spins in the CNTs. We observed a clear correlation between the ESR decrease and the current increase under high charge density conditions, which directly demonstrated electrically induced ambipolar spin vanishments in the CNTs. The result provides a first clear evidence of antimagnetic interactions between spins of electrically induced charge carriers and vacancies in the CNTs. The ambipolar spin vanishments would contribute the improvement of transport properties of CNTs because of greatly reduced carrier scatterings.
Mechanistic studies of a novel C-S lyase in ergothioneine biosynthesis: the involvement of a sulfenic acid intermediate
Authors: Song Heng , Hu Wen , Naowarojna Nathchar , Her Ampon Sae , Wang Shu , Desai Rushil , Qin Li , Chen Xiaoping , Liu Pinghua
Published: July 2015

Ergothioneine is a histidine thio-derivative isolated in 1909. In ergothioneine biosynthesis, the combination of a mononuclear non-heme iron enzyme catalyzed oxidative C-S bond formation reaction and a PLP-mediated C-S lyase (EgtE) reaction results in a net sulfur transfer from cysteine to histidine side-chain. This demonstrates a new sulfur transfer strategy in the biosynthesis of sulfur-containing natural products. Due to difficulties associated with the overexpression of Mycobacterium smegmatis EgtE protein, the proposed EgtE functionality remained to be verified biochemically. In this study, we have successfully overexpressed and purified M. smegmatis EgtE enzyme and evaluated its activities under different in vitro conditions: C-S lyase reaction using either thioether or sulfoxide as a substrate in the presence or absence of reductants. Results from our biochemical characterizations support the assignment of sulfoxide 4 as the native EgtE substrate and the involvement of a sulfenic acid intermediate in the ergothioneine C-S lyase reaction.
Intravitreal TSG-6 suppresses laser-induced choroidal neovascularization by inhibiting CCR2+ monocyte recruitment
Authors: Jin Kim Sang , Ju Lee Hyun , Yun Ji-Hyun , Hwa Ko Jung , Choi Da Ye , Youn Oh Joo
Published: July 2015

Choroidal neovascularization (CNV) is the hallmark of wet age-related macular degeneration (AMD), one of the leading causes of blindness in the elderly. Although the pathogenesis of CNV is not clear, a number of studies show that ocular-infiltrating macrophages and inflammation play a critical role in the development of CNV. TNFα-stimulated gene/protein (TSG)-6 is a multifunctional endogenous protein that has anti-inflammatory activities partly by regulating macrophage activation. Therefore, we here investigated the therapeutic potential of TSG-6 in a rat model of CNV induced by laser photocoagulation. Time course analysis showed that the expression of VEGF and pro-inflammatory cytokines in the choroid was up-regulated early after laser injury and gradually decreased to baseline over 14 days. An intravitreal injection of TSG-6 suppressed the expression of VEGF and pro-inflammatory cytokines including CCL2 and reduced the size of CNV. Also, the number of Iba+ and CCR2+ cells including infiltrating macrophages was markedly lower in the CNV lesion of TSG-6-treated eyes. Further analysis identified CCR2+ CD11b+ CD11c+ cells and CCR2+ CD11b-CD11c+ cells as the cell populations that were increased by laser injury and reduced by TSG-6 treatment. Together, the results demonstrate that TSG-6 inhibits inflammation and CCR2+ monocyte recruitment into the choroid and suppresses the development of CNV.
Quantitative constraint-based computational model of tumor-to-stroma coupling via lactate shuttle
Authors: Capuani Fabrizio , De Martino Daniele , Marinari Enzo , De Martino Andrea
Published: July 2015

Cancer cells utilize large amounts of ATP to sustain growth, relying primarily on non-oxidative, fermentative pathways for its production. In many types of cancers this leads, even in the presence of oxygen, to the secretion of carbon equivalents (usually in the form of lactate) in the cell’s surroundings, a feature known as the Warburg effect. While the molecular basis of this phenomenon are still to be elucidated, it is clear that the spilling of energy resources contributes to creating a peculiar microenvironment for tumors, possibly characterized by a degree of toxicity. This suggests that mechanisms for recycling the fermentation products (e.g. a lactate shuttle) may be active, effectively inducing a mutually beneficial metabolic coupling between aberrant and non-aberrant cells. Here we analyze this scenario through a large-scale in silico metabolic model of interacting human cells. By going beyond the cell-autonomous description, we show that elementary physico-chemical constraints indeed favor the establishment of such a coupling under very broad conditions. The characterization we obtained by tuning the aberrant cell’s demand for ATP, amino-acids and fatty acids and/or the imbalance in nutrient partitioning provides quantitative support to the idea that synergistic multi-cell effects play a central role in cancer sustainment.
Trapped lipopolysaccharide and LptD intermediates reveal lipopolysaccharide translocation steps across the Escherichia coli outer membrane
Authors: Li Xuejun , Gu Yinghong , Dong Haohao , Wang Wenjian , Dong Changjiang
Published: July 2015

Lipopolysaccharide (LPS) is a main component of the outer membrane of Gram-negative bacteria, which is essential for the vitality of most Gram-negative bacteria and plays a critical role for drug resistance. LptD/E complex forms a N-terminal LPS transport slide, a hydrophobic intramembrane hole and the hydrophilic channel of the barrel, for LPS transport, lipid A insertion and core oligosaccharide and O-antigen polysaccharide translocation, respectively. However, there is no direct evidence to confirm that LptD/E transports LPS from the periplasm to the external leaflet of the outer membrane. By replacing LptD residues with an unnatural amino acid p-benzoyl-L-phenyalanine (pBPA) and UV-photo-cross-linking in E.coli, the translocon and LPS intermediates were obtained at the N-terminal domain, the intramembrane hole, the lumenal gate, the lumen of LptD channel and the extracellular loop 1 and 4, providing the first direct evidence and “snapshots” to reveal LPS translocation steps across the outer membrane.
Dielectric Optical-Controllable Magnifying Lens by Nonlinear Negative Refraction
Authors: Cao Jianjun , Shang Ce , Zheng Yuanlin , Feng Yaming , Chen Xianfeng , Liang Xiaogan , Wan Wenjie
Published: July 2015

A simple optical lens plays an important role for exploring the microscopic world in science and technology by refracting light with tailored spatially varying refractive indices. Recent advancements in nanotechnology enable novel lenses, such as, superlens and hyperlens, with sub-wavelength resolution capabilities by specially designed materials’ refractive indices with meta-materials and transformation optics. However, these artificially nano- or micro-engineered lenses usually suffer high losses from metals and are highly demanding in fabrication. Here, we experimentally demonstrate, for the first time, a nonlinear dielectric magnifying lens using negative refraction by degenerate four-wave mixing in a plano-concave glass slide, obtaining magnified images. Moreover, we transform a nonlinear flat lens into a magnifying lens by introducing transformation optics into the nonlinear regime, achieving an all-optical controllable lensing effect through nonlinear wave mixing, which may have many potential applications in microscopy and imaging science.
Protein alterations in women with chronic widespread pain – An explorative proteomic study of the trapezius muscle
Authors: Olausson Patrik , Gerdle Björn , Ghafouri Nazdar , Sjöström Dick , Blixt Emelie , Ghafouri Bijar
Published: July 2015

Chronic widespread pain (CWP) has a high prevalence in the population and is associated with prominent negative individual and societal consequences. There is no clear consensus concerning the etiology behind CWP although alterations in the central processing of nociception maintained by peripheral nociceptive input has been suggested. Here, we use proteomics to study protein changes in trapezius muscle from 18 female patients diagnosed with CWP compared to 19 healthy female subjects. The 2-dimensional gel electrophoresis (2-DE) in combination with multivariate statistical analyses revealed 17 proteins to be differently expressed between the two groups. Proteins were identified by mass spectrometry. Many of the proteins are important enzymes in metabolic pathways like the glycolysis and gluconeogenesis. Other proteins are associated with muscle damage, muscle recovery, stress and inflammation. The altered expressed levels of these proteins suggest abnormalities and metabolic changes in the myalgic trapezius muscle in CWP. Taken together, this study gives further support that peripheral factors may be of importance in maintaining CWP.
Survival in patchy landscapes: the interplay between dispersal, habitat loss and fragmentation
Authors: Niebuhr Bernardo B. S. , Wosniack Marina E. , Santos Marcos C. , Raposo Ernesto P. , Viswanathan Gandhimohan M. , da Luz Marcos G. E. , Pie Marcio R.
Published: July 2015

Habitat loss and fragmentation are important factors determining animal population dynamics and spatial distribution. Such landscape changes can lead to the deleterious impact of a significant drop in the number of species, caused by critically reduced survival rates for organisms. In order to obtain a deeper understanding of the threeway interplay between habitat loss, fragmentation and survival rates, we propose here a spatially explicit multi-scaled movement model of individuals that search for habitat. By considering basic ecological processes, such as predation, starvation (outside the habitat area) and competition, together with dispersal movement as a link among habitat areas, we show that a higher survival rate is achieved in instances with a lower number of patches of larger areas. Our results demonstrate how movement may counterbalance the effects of habitat loss and fragmentation in altered landscapes. In particular, they have important implications for conservation planning and ecosystem management, including the design of specific features of conservation areas in order to enhance landscape connectivity and population viability.
Two Types of Discontinuous Percolation Transitions in Cluster Merging Processes
Authors: Cho Y. S. , Kahng B.
Published: July 2015

Percolation is a paradigmatic model in disordered systems and has been applied to various natural phenomena. The percolation transition is known as one of the most robust continuous transitions. However, recent extensive studies have revealed that a few models exhibit a discontinuous percolation transition (DPT) in cluster merging processes. Unlike the case of continuous transitions, understanding the nature of discontinuous phase transitions requires a detailed study of the system at hand, which has not been undertaken yet for DPTs. Here we examine the cluster size distribution immediately before an abrupt increase in the order parameter of DPT models and find that DPTs induced by cluster merging kinetics can be classified into two types. Moreover, the type of DPT can be determined by the key characteristic of whether the cluster kinetic rule is homogeneous with respect to the cluster sizes. We also establish the necessary conditions for each type of DPT, which can be used effectively when the discontinuity of the order parameter is ambiguous, as in the explosive percolation model.
Quantitative and qualitative analysis of the novel antitumor 1,3,4-oxadiazole derivative (GLB) and its metabolites using HPLC-UV and UPLC-QTOF-MS
Authors: Li Pu , Wang Xin , Li Jian , Meng Zhi-Yun , Li Shu-Chun , Li Zhong-Jun , Lu Ying-Yuan , Ren Hong , Lou Ya-Qing , Lu Chuang , Dou Gui-Fang , Zhang Guo-Liang
Published: July 2015

Fructose-based 3-acetyl-2,3-dihydro-1,3,4-oxadiazole (GLB) is a novel antitumor agent and belongs to glycosylated spiro-heterocyclic oxadiazole scaffold derivative. This research first reported a simple, specific, sensitive and stable high performance liquid chromatography -ultraviolet detector (HPLC-UV) method for the quantitative determination of GLB in plasma. In this method, the chromatographic separation was achieved with a reversed phase C18 column. The calibration curve for GLB was linear at 300 nm. The lower limit of quantification was 10 ng/mL. The precision, accuracy and stability of the method were validated adequately. This method was successfully applied to the pharmacokinetic study in rats for detection of GLB after oral administration. Moreover, the structures of parent compound GLB and its two major metabolites M1 and M2 were identified in plasma using an ultra performance liquid chromatography- electrospray ionization-quadrupole-time of flight- mass spectrometry (UPLC-ESI-QTOF-MS) method. Our results indicated that the di-hydroxylation (M1) and hydroxylation (M2) of GLB are the major metabolites. In conclusion, the present study provided valuable information on an analytical method for the determination of GLB and its metabolites in rats, can be used to support further developing of this antitumor agent.
Structural Evolution of Chemically-Driven RuO2 Nanowires and 3-Dimensional Design for Photo-Catalytic Applications
Authors: Park Joonmo , Lee Jae Won , Ye Byeong Uk , Chun Sung Hee , Joo Sang Hoon , Park Hyunwoong , Lee Heon , Jeong Hu Young , Kim Myung Hwa , Baik Jeong Min
Published: July 2015

Growth mechanism of chemically-driven RuO2 nanowires is explored and used to fabricate three-dimensional RuO2 branched Au-TiO2 nanowire electrodes for the photostable solar water oxidation. For the real time structural evolution during the nanowire growth, the amorphous RuO2 precursors (Ru(OH)3·H2O) are heated at 180 °C, producing the RuO2 nanoparticles with the tetragonal crystallographic structure and Ru enriched amorphous phases, observed through the in-situ synchrotron x-ray diffraction and the high-resolution transmission electron microscope images. Growth then proceeds by Ru diffusion to the nanoparticles, followed by the diffusion to the growing surface of the nanowire in oxygen ambient, supported by the nucleation theory. The RuO2 branched Au-TiO2 nanowire arrays shows a remarkable enhancement in the photocurrent density by approximately 60% and 200%, in the UV-visible and Visible region, respectively, compared with pristine TiO2 nanowires. Furthermore, there is no significant decrease in the device’s photoconductance with UV-visible illumination during 1 day, making it possible to produce oxygen gas without the loss of the photoactvity.
Two short sequences in OsNAR2.1 promoter are necessary for fully activating the nitrate induced gene expression in rice roots
Authors: Liu Xiaoqin , Feng Huimin , Huang Daimin , Song Miaoquan , Fan Xiaorong , Xu Guohua
Published: July 2015

Nitrate is an essential nitrogen source and serves as a signal to control growth and gene expression in plants. In rice, OsNAR2.1 is an essential partner of multiple OsNRT2 nitrate transporters for nitrate uptake over low and high concentration range. Previously, we have reported that −311 bp upstream fragment from the translational start site in the promoter of OsNAR2.1 gene is the nitrate responsive region. To identify the cis-acting DNA elements necessary for nitrate induced gene expression, we detected the expression of beta-glucuronidase (GUS) reporter in the transgenic rice driven by the OsNAR2.1 promoter with different lengths and site mutations of the 311 bp region. We found that −129 to −1 bp region is necessary for the nitrate-induced full activation of OsNAR2.1. Besides, the site mutations showed that the 20 bp fragment between −191 and −172 bp contains an enhancer binding site necessary to fully drive the OsNAR2.1 expression. Part of the 20 bp fragment is commonly presented in the sequences of different promoters of both the nitrate induced NAR2 genes and nitrite reductase NIR1 genes from various higher plants. These findings thus reveal the presence of conserved cis-acting element for mediating nitrate responses in plants.
Maskless Lithography and in situ Visualization of Conductivity of Graphene using Helium Ion Microscopy
Authors: Iberi Vighter , Vlassiouk Ivan , Zhang X.-G. , Matola Brad , Linn Allison , Joy David C. , Rondinone Adam J.
Published: July 2015

The remarkable mechanical and electronic properties of graphene make it an ideal candidate for next generation nanoelectronics. With the recent development of commercial-level single-crystal graphene layers, the potential for manufacturing household graphene-based devices has improved, but significant challenges still remain with regards to patterning the graphene into devices. In the case of graphene supported on a substrate, traditional nanofabrication techniques such as e-beam lithography (EBL) are often used in fabricating graphene nanoribbons but the multi-step processes they require can result in contamination of the graphene with resists and solvents. In this letter, we report the utility of scanning helium ion lithography for fabricating functional graphene nanoconductors that are supported directly on a silicon dioxide layer and we measure the minimum feature size achievable due to limitations imposed by thermal fluctuations and ion scattering during the milling process. Further we demonstrate that ion beams, due to their positive charging nature, may be used to observe and test the conductivity of graphene-based nanoelectronic devices in situ.
Metabonomic analysis of potential biomarkers and drug targets involved in diabetic nephropathy mice
Authors: Wei Tingting , Zhao Liangcai , Jia Jianmin , Xia Huanhuan , Du Yao , Lin Qiuting , Lin Xiaodong , Ye Xinjian , Yan Zhihan , Gao Hongchang
Published: July 2015

Diabetic nephropathy (DN) is one of the lethal manifestations of diabetic systemic microvascular disease. Elucidation of characteristic metabolic alterations during diabetic progression is critical to understand its pathogenesis and identify potential biomarkers and drug targets involved in the disease. In this study, 1H nuclear magnetic resonance (1H NMR)-based metabonomics with correlative analysis was performed to study the characteristic metabolites, as well as the related pathways in urine and kidney samples of db/db diabetic mice, compared with age-matched wildtype mice. The time trajectory plot of db/db mice revealed alterations, in an age-dependent manner, in urinary metabolic profiles along with progression of renal damage and dysfunction. Age-dependent and correlated metabolite analysis identified that cis-aconitate and allantoin could serve as biomarkers for the diagnosis of DN. Further correlative analysis revealed that the enzymes dimethylarginine dimethylaminohydrolase (DDAH), guanosine triphosphate cyclohydrolase I (GTPCH I) and 3-hydroxy-3-methylglutaryl-CoA lyase (HMG-CoA lyase) were involved in dimethylamine metabolism, ketogenesis and GTP metabolism pathways, respectively and could be potential therapeutic targets for DN. Our results highlight that metabonomic analysis can be used as a tool to identify potential biomarkers and novel therapeutic targets to gain a better understanding of the mechanisms underlying the initiation and progression of diseases.
Serum pro-BDNF/BDNF as a treatment biomarker for response to docosahexaenoic acid in traumatized people vulnerable to developing psychological distress: a randomized controlled trial
Authors: Matsuoka Y , Nishi D , Tanima Y , Itakura M , Kojima M , Hamazaki K , Noguchi H , Hamazaki T
Published: July 2015

Our open-label pilot study showed that supplementation with docosahexaenoic acid (DHA) increased serum brain-derived neurotrophic factor (BDNF) levels and that there might be an association between changes in serum BDNF levels and reduced psychological distress. Animal research has indicated that a DHA-enriched diet increases BDNF in the brain. In this randomized double-blind controlled trial of severely injured patients vulnerable to posttraumatic stress disorder (PTSD) and depression, we examined whether DHA increases serum BDNF levels and whether changes in BDNF levels are associated with subsequent symptoms of PTSD and depression. Patients received 1470 mg per day of DHA plus 147 mg per day of eicosapentaenoic acid (EPA; n=53) or placebo (n=57) for 12 weeks. Serum levels of mature BDNF and precursor pro-BDNF at baseline and 12-week follow-up were measured using enzyme-linked immunosorbent assay kits. At 12 weeks, we used the Clinician-Administered PTSD Scale to assess PTSD symptoms and depressive symptoms by the Montgomery–Åsberg Depression Rating Scale. We found a significant increase in serum BDNF levels during the trial in the DHA and placebo groups with no interaction between time and group. Changes in BDNF levels were not associated with PTSD severity but negatively associated with depression severity (Spearman’s ρ=−0.257, P=0.012). Changes in pro-BDNF were also negatively associated with depression severity (Spearman’s ρ=−0.253, P=0.013). We found no specific effects of DHA on increased serum levels of BDNF and pro-BDNF; however, evidence in this study suggests that increased BDNF and pro-BDNF have a protective effect by minimizing depression severity.
Coumarin heterocyclic derivatives: chemical synthesis and biological activity
Authors: Medina Fernanda G. , Marrero Joaquín G. , Macías-Alonso Mariana , González Magdalena C. , Córdova-Guerrero Iván , Teissier García Ariana G. , Osegueda-Robles Soraya
Published: July 2015

This review highlights the broad range of science that has arisen from the synthesis of coumarin-linked and fused heterocycle derivatives.
A miniaturized electrochemical assay for homocysteine using screen-printed electrodes with cytochrome c anchored gold nanoparticles
Authors: Madasamy Thangamuthu , Santschi Christian , Martin Olivier J. F.
Published: July 2015

Electrochemical point-of-care analysis of homocysteine in a drop of the blood plasma samples.
Sensitive electrochemical detection of vaccinia virus in a solution containing a high concentration ofl-ascorbic acid
Authors: Park Seonhwa , Kim Jihye , Ock Hwiseok , Dutta Gorachand , Seo Jeongwook , Shin Eui-Cheol , Yang Haesik
Published: July 2015

A new redox cycling scheme allows sensitive detection of vaccinia virus in a solution containing a high concentration ofl-ascorbic acid.
A HT column GC/MS method for the determination of anthraquinone and its toxic impurities in paper products
Authors: Yang Ki-Ryeol , Seo Hee Seung , Lee Yong Sup , Choi Man Ho , Hong Jongki
Published: July 2015

A high-temperature (HT) column gas chromatography-mass spectrometry (GC/MS) method was developed and validated for the measurement of anthraquinone (AQ) and its toxic impurities in various paper food packaging products.
Ultrasound assisted-cloud point extraction combined with flame atomic absorption spectrometry for selective preconcentration and determination of As(v) in selected water and beverage samples
Authors: Altunay Nail , Gürkan Ramazan , Kır Ufuk
Published: July 2015

A new UA-CPE method was efficiently combined with FAAS for detection of As(v). The method is based on the ion-association of As(v) with NRH+ in the presence of pyrogallol. A detection limit of 0.45 μg L-1 for As(v) was achieved.
Fingerprint analysis and quantitative determination of 16 constituents of Antike capsule by high-performance liquid chromatography-photodiode array detection
Authors: Duan Linrui , Li Hua , Yuan Jiani , Zhao Hang , Zhang Xiaokai , Zhou Xuanxuan , Yang Qian , Cao Wei , Xie Yanhua , Miao Shan , Wang Siwang
Published: July 2015

A method was developed using high-performance liquid chromatography-photodiode array detection to obtain a chromatographic fingerprint of Antike capsule.
Quantification of ethanol using a luminescence system derived from Photobacterium leiognathi
Authors: Xuan Guanhua , Lu Xiaodong , Wang Jingxue , Lin Hong , Xiao Qilin
Published: July 2015

A luminescence system derived fromPhotobacterium leiognathishows advantages such as high specificity, good repeatability and ease of operation. Therefore, it could be an advantageous alternative method for accurate quantification of ethanol content in beer.
Efficient and highly selective boron-doped carbon materials-catalyzed reduction of nitroarenes
Authors: Lin Yangming , Wu Shuchang , Shi Wen , Zhang Bingsen , Wang Jia , Kim Yoong Ahm , Endo Morinobu , Su Dang Sheng
Published: July 2015

Boron-doped carbon materials are demonstrated to be excellent catalysts in nitroarene reduction reactions.
A contamination-insensitive probe for imaging specific biomolecules by secondary ion mass spectrometry
Authors: Kabatas Selda , Vreja Ingrid C. , Saka Sinem K. , Höschen Carmen , Kröhnert Katharina , Opazo Felipe , Rizzoli Silvio O. , Diederichsen Ulf
Published: July 2015

Design of a protein label containing 15N, 14N and 19F-isotopes and a fluorophore for both confocal microscopy and nanoscale secondary ion mass spectrometry (NanoSIMS).
Glass formation via structural fragmentation of a 2D coordination network
Authors: Umeyama D. , Funnell N. P. , Cliffe M. J. , Hill J. A. , Goodwin A. L. , Hijikata Y. , Itakura T. , Okubo T. , Horike S. , Kitagawa S.
Published: July 2015

Flexible coordination bonds enable glass formation from a coordination network crystal via 2D-to-0D structural transformation.
Assorted morphosynthesis: access to multi-faceted nano-architectures from a super-responsive dual π-functional amphiphilic construct
Authors: Asthana Deepak , Shukla Jyoti , Dana Srikanta , Rani Varsha , Ajayakumar M. R. , Rawat Kamla , Mandal Kalyanashis , Yadav Premlata , Ghosh Subhasis , Mukhopadhyay Pritam
Published: July 2015

An electronically segmented amphiphile was created by conjugating two π-functional units (HQ/NDI) for the first time.
Correction: Glycosylation enhances the aqueous sensitivity and lowers the cytotoxicity of a naphthalimide zinc ion fluorescence probe
Authors: Dong Lei , Zang Yi , Zhou Dan , He Xiao-Peng , Chen Guo-Rong , James Tony D. , Li Jia
Published: July 2015

Correction for ‘Glycosylation enhances the aqueous sensitivity and lowers the cytotoxicity of a naphthalimide zinc ion fluorescence probe’ by Lei Dong et al., Chem. Commun., 2015, DOI: 10.1039/c5cc04357c.
Correction: Emerging approaches for the synthesis of triazoles: beyond metal-catalyzed and strain-promoted azide–alkyne cycloaddition
Authors: Lima Carolina G. S. , Ali Akbar , van Berkel Sander S. , Westermann Bernhard , Paixão Márcio W.
Published: July 2015

Correction for 'Emerging approaches for the synthesis of triazoles: beyond metal-catalyzed and strain-promoted azide–alkyne cycloaddition' by Carolina G. S. Lima et al., Chem. Commun., 2015, 51, 10784–10796.
Water-induced room-temperature transformation of straight Ge/Si core/shell nanowires into circular silica nanotubes
Authors: Lee Ji Eun , Kim Byeong Geun , Kim Byung-Sung , Whang Dongmok , Choi Heon-Jin , Choi Soon-Mok , Seo Won-Seon , Jeong Seong-Min
Published: July 2015

A facile method for producing circular silica nanotubes starting from straight Ge/Si core/shell nanowires is introduced.
Electromagnetic interference shielding in 1–18 GHz frequency and electrical property correlations in poly(vinylidene fluoride)–multi-walled carbon nanotube composites
Authors: Kumar G. Sudheer , Vishnupriya D. , Joshi Anupama , Datar Suwarna , Patro T. Umasankar
Published: July 2015

A dilute acid-treatment of MWNT showed a low electrical percolation in PVDF and significant improvements in EMI shielding properties.