bluuebunny/crossref_metadata_2025 huggingface dataset:
Epitaxial growth of highly-crystalline spinel ferrite thin films on perovskite substrates for all-oxide devices
Authors: Moyer Jarrett A. , Gao Ran , Schiffer Peter , Martin Lane W.
Published: June 2015

The potential growth modes for epitaxial growth of Fe3O4 on SrTiO3 (001) are investigated through control of the energetics of the pulsed-laser deposition growth process (via substrate temperature and laser fluence). We find that Fe3O4 grows epitaxially in three distinct growth modes: 2D-like, island and 3D-to-2D, the last of which is characterized by films that begin growth in an island growth mode before progressing to a 2D growth mode. Films grown in the 2D-like and 3D-to-2D growth modes are atomically flat and partially strained, while films grown in the island growth mode are terminated in islands and fully relaxed. We find that the optimal structural, transport and magnetic properties are obtained for films grown on the 2D-like/3D-to-2D growth regime boundary. The viability for including such thin films in perovskite-based all-oxide devices is demonstrated by growing a Fe3O4/La0.7Sr0.3MnO3 spin valve epitaxially on SrTiO3.
Self-organized criticality in cortical assemblies occurs in concurrent scale-free and small-world networks
Authors: Massobrio Paolo , Pasquale Valentina , Martinoia Sergio
Published: June 2015

The spontaneous activity of cortical networks is characterized by the emergence of different dynamic states. Although several attempts were accomplished to understand the origin of these dynamics, the underlying factors continue to be elusive. In this work, we specifically investigated the interplay between network topology and spontaneous dynamics within the framework of self-organized criticality (SOC). The obtained results support the hypothesis that the emergence of critical states occurs in specific complex network topologies. By combining multi-electrode recordings of spontaneous activity of in vitro cortical assemblies with theoretical models, we demonstrate that different ‘connectivity rules’ drive the network towards different dynamic states. In particular, scale-free architectures with different degree of small-worldness account better for the variability observed in experimental data, giving rise to different dynamic states. Moreover, in relationship with the balance between excitation and inhibition and percentage of inhibitory hubs, the simulated cortical networks fall in a critical regime.
Molecular pathway of near-infrared laser phototoxicity involves ATF-4 orchestrated ER stress
Authors: Khan Imran , Tang Elieza , Arany Praveen
Published: June 2015

High power lasers are used extensively in medicine while lower power applications are popular for optical imaging, optogenetics, skin rejuvenation and a therapeutic modality termed photobiomodulation (PBM). This study addresses the therapeutic dose limits, biological safety and molecular pathway of near-infrared (NIR) laser phototoxicity. Increased erythema and tissue damage were noted in mice skin and cytotoxicity in cell cultures at phototoxic laser doses involving generation of reactive oxygen species (ROS) coupled with a rise in surface temperature (>45 °C). NIR laser phototoxicity results from Activating Transcription Factor-4 (ATF-4) mediated endoplasmic reticulum stress and autophagy. Neutralizations of heat or ROS and overexpressing ATF-4 were noted to rescue NIR laser phototoxicity. Further, NIR laser mediated phototoxicity was noted to be non-genotoxic and non-mutagenic. This study outlines the mechanism of NIR laser phototoxicity and the utility of monitoring surface temperature and ATF4 expression as potential biomarkers to develop safe and effective clinical applications.
Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis
Authors: Dang Wei , Zhang Wen , Du Wei-Guo
Published: June 2015

Identifying how developmental temperature affects the immune system is critical for understanding how ectothermic animals defend against pathogens and their fitness in the changing world. However, reptiles have received little attention regarding this issue. We incubated eggs at three ecologically relevant temperatures to determine how incubation temperature affects the immune function of hatchling soft-shelled turtles,Pelodiscus sinensis. When exposed to bacterial infections, hatchlings from 24 °C had lower cumulative mortalities (55%, therefore, higher immunocompetence) than those from 28 °C (85%) or 32 °C (100%). Consistent with higher immunocompetence, hatchlings from low incubation temperature had higher IgM, IgD and CD3γ expressions than their counterparts from the other two higher incubation temperatures. Conversely, the activity of immunity-related enzymes did not match the among-temperature difference in immune function. Specifically, enzyme activity was higher at intermediate temperatures (alkaline phosphatase) or was not affected by incubation temperature (acid phosphatase, lysozyme). Our study is the first to provide unequivocal evidence (at the molecular and organismal level) about the significant effect of incubation temperature on offspring immunity in reptiles. Our results also indicate that the reduced immunity induced by high developmental temperatures might increase the vulnerability of reptiles to the outbreak of diseases under global warming scenarios.
TiO2 Fibers Supported β-FeOOH Nanostructures as Efficient Visible Light Photocatalyst and Room Temperature Sensor
Authors: Zhu Ting , Li Ong Wei , Zhu Liangliang , Wei Ho Ghim
Published: June 2015

Hierarchical heterostructures of beta-iron oxyhydroxide (β-FeOOH) nanostructures on electrospun TiO2 nanofibers were synthesized by a facile hydrothermal method. This synthesis method proves to be versatile to tailoring of β-FeOOH structural design that cuts across zero-dimensional particles (TF-P), one-dimensional needles (TF-N) to two-dimensional flakes (TF-F). In addition, synthesizing such oxyhyroxide nanostructures presents the advantage of exhibiting similar functional performances to its oxides counterpart however, without the need to undergo any annealing step which leads to undesirable structural collapse or sintering. The as-prepared hierarchical heterostructures possess high surface area for dye adsorptivity, efficient charge separation and visible photocatalytic activity. Also, for the first time, hydrogen gas sensing has been demonstrated on β-FeOOH nanostructures at room temperature. The reported hierarchical heterostructures of β-FeOOH on TiO2 nanofibers afford multiple functions of photocatalysis and sensing which are highly promising for environment monitoring and clean up applications.
Continuous Metabolic Monitoring Based on Multi-Analyte Biomarkers to Predict Exhaustion
Authors: Kastellorizios Michail , Burgess Diane J.
Published: June 2015

This work introduces the concept of multi-analyte biomarkers for continuous metabolic monitoring. The importance of using more than one marker lies in the ability to obtain a holistic understanding of the metabolism. This is showcased for the detection and prediction of exhaustion during intense physical exercise. The findings presented here indicate that when glucose and lactate changes over time are combined into multi-analyte biomarkers, their monitoring trends are more sensitive in the subcutaneous tissue, an implantation-friendly peripheral tissue, compared to the blood. This unexpected observation was confirmed in normal as well as type 1 diabetic rats. This study was designed to be of direct value to continuous monitoring biosensor research, where single analytes are typically monitored. These findings can be implemented in new multi-analyte continuous monitoring technologies for more accurate insulin dosing, as well as for exhaustion prediction studies based on objective data rather than the subject’s perception.
Giant enhancement in critical current density, up to a hundredfold, in superconducting NaFe0.97Co0.03 As single crystals under hydrostatic pressure
Authors: Shabbir Babar , Wang Xiaolin , Ghorbani S. R. , Wang A. F. , Dou Shixue , Chen X. H.
Published: June 2015

Tremendous efforts towards improvement in the critical current density “Jc” of iron based superconductors (FeSCs), especially at relatively low temperatures and magnetic fields, have been made so far through different methods, resulting in real progress. Jc at high temperatures in high fields still needs to be further improved, however, in order to meet the requirements of practical applications. Here, we demonstrate a simple approach to achieve this. Hydrostatic pressure can significantly enhance Jc in NaFe0.97Co0.03As single crystals by at least tenfold at low field and more than a hundredfold at high fields. Significant enhancement in the in-field performance of NaFe0.97Co0.03As single crystal in terms of pinning force density (Fp) is found at high pressures. At high fields, the Fp is over 20 and 80 times higher than under ambient pressure at12 K and 14 K, respectively, at P = 1 GPa. We believe that the Co-doped NaFeAs compounds are very exciting and deserve to be more intensively investigated. Finally, it is worthwhile to say that by using hydrostatic pressure, we can achieve more milestones in terms of high Jc values in tapes, wires or films of other Fe-based superconductors.
Absence of Structural Impact of Noble Nanoparticles on P3HT:PCBM Blends for Plasmon-Enhanced Bulk-Heterojunction Organic Solar Cells Probed by Synchrotron GI-XRD
Authors: Lilliu Samuele , Alsari Mejd , Bikondoa Oier , Emyr Macdonald J. , Dahlem Marcus S.
Published: June 2015

The incorporation of noble metal nanoparticles, displaying localized surface plasmon resonance, in the active area of donor-acceptor bulk-heterojunction organic photovoltaic devices is an industrially compatible light trapping strategy, able to guarantee better absorption of the incident photons and give an efficiency improvement between 12% and 38%. In the present work, we investigate the effect of Au and Ag nanoparticles blended with P3HT: PCBM on the P3HT crystallization dynamics by synchrotron grazing incidence X-ray diffraction. We conclude that the presence of (1) 80 nm Au, (2) mix of 5 nm, 50 nm, 80 nm Au, (3) 40 nm Ag and (4) 10 nm, 40 nm, 60 nm Ag colloidal nanoparticles, at different concentrations below 0.3 wt% for Au and below 0.1% for Ag in P3HT: PCBM blends, does not affect the behaviour of the blends themselves.
Thin-film ‘Thermal Well’ Emitters and Absorbers for High-Efficiency Thermophotovoltaics
Authors: Tong Jonathan K. , Hsu Wei-Chun , Huang Yi , Boriskina Svetlana V. , Chen Gang
Published: June 2015

A new approach is introduced to significantly improve the performance of thermophotovoltaic (TPV) systems using low-dimensional thermal emitters and photovoltaic (PV) cells. By reducing the thickness of both the emitter and the PV cell, strong spectral selectivity in thermal emission and absorption can be achieved by confining photons in trapped waveguide modes inside the thin-films that act as thermal analogs to quantum wells. Simultaneously, photo-excited carriers travel shorter distances across the thin-films reducing bulk recombination losses resulting in a lower saturation current in the PV cell. We predict a TPV efficiency enhancement with near-field coupling between the thermal emitter and the PV cell up to 38.7% using a thin-film germanium (Ge) emitter at 1000 K and an ultra-thin gallium antimonide (GaSb) cell supported by perfect back reflectors separated by 100 nm. Even in the far-field limit, the efficiency is predicted to reach 31.5%, which is over an order of magnitude higher than the Shockley Queisser limit of 1.6% for a bulk GaSb cell and a blackbody emitter at 1000 K. The proposed design approach does not require nanoscale patterning of the emitter and PV cell surfaces, but instead offers a simple low-cost solution to improve the performance of thermophotovoltaic systems.
Disruption of Thermally-Stable Nanoscale Grain Structures by Strain Localization
Authors: Khalajhedayati Amirhossein , Rupert Timothy J.
Published: June 2015

Nanocrystalline metals with average grain sizes of only a few nanometers have recently been observed to fail through the formation of shear bands. Here, we investigate this phenomenon in nanocrystalline Ni which has had its grain structure stabilized by doping with W, with a specific focus on understanding how strain localization drives evolution of the nanoscale grain structure. Shear banding was initiated with both microcompression and nanoindentation experiments, followed by site-specific transmission electron microscopy to characterize the microstructure. Grain growth and texture formation were observed inside the shear bands, which had a wide variety of thicknesses. These evolved regions have well-defined edges, which rules out local temperature rise as a possible formation mechanism. No structural evolution was found in areas away from the shear bands, even in locations where significant plastic deformation had occurred, showing that plastic strain alone is not enough to cause evolution. Rather, intense strain localization is needed to induce mechanically-driven grain growth in a thermally-stable nanocrystalline alloy.
High-mobility and air-stable single-layer WS2 field-effect transistors sandwiched between chemical vapor deposition-grown hexagonal BN films
Authors: Iqbal M Waqas , Iqbal M Zahir , Khan M Farooq , Shehzad M Arslan , Seo Yongho , Park Jong Hyun , Hwang Chanyong , Eom Jonghwa
Published: June 2015

An emerging electronic material as one of transition metal dichalcogenides (TMDCs), tungsten disulfide (WS2) can be exfoliated as an atomically thin layer and can compensate for the drawback of graphene originating from a gapless band structure. A direct bandgap, which is obtainable in single-layer WS2, is an attractive characteristic for developing optoelectronic devices, as well as field-effect transistors. However, its relatively low mobility and electrical characteristics susceptible to environments remain obstacles for the use of device materials. Here, we demonstrate remarkable improvement in the electrical characteristics of single-layer WS2field-effect transistor (SL-WS2FET) using chemical vapor deposition (CVD)-grown hexagonal BN (h-BN). SL-WS2FET sandwiched between CVD-grown h-BN films shows unprecedented high mobility of 214 cm2/Vs at room temperature. The mobility of a SL-WS2FET has been found to be 486 cm2/Vs at 5 K. The ON/OFF ratio of output current is ~107at room temperature. Apart from an ideal substrate for WS2FET, CVD-grown h-BN film also provides a protection layer against unwanted influence by gas environments. The h-BN/SL-WS2/h-BN sandwich structure offers a way to develop high-quality durable single-layer TMDCs electronic devices.
Myo-inositol improves the host’s ability to eliminate balofloxacin-resistant Escherichia coli
Authors: Chen Xin-hai , Zhang Bing-wen , Li Hui , Peng Xuan-xian
Published: June 2015

Antibiotic-resistant mechanisms are associated with fitness costs. However, why antibiotic-resistant bacteria usually show increasing adaptation to hosts is largely unknown, especially from the host’s perspective. The present study reveals the host’s varied response to balofloxacin-resistant Escherichia coli (BLFX-R) using an integrated proteome and metabolome approach and identifies myo-inositol and phagocytosis-related proteins as crucial biomarkers. Originally, macrophages have an optimal attractive preference to BLFX-S due to more polarization of BLFX-S than BLFX-R, which renders faster elimination to BLFX-S than BLFX-R. The slower elimination to BLFX-R may be reversed by exogenous myo-inositol. Primarily, myo-inositol depolarizes macrophages, elevating adherence to both BLFX-S and BLFX-R. Since the altered adherence is equal to both strains, the myo-inositol-treated macrophages are free of the barrier to BLFX-R and thereby promote phagocytosis of BLFX-R. This work provides a novel strategy based on metabolic modulation for eliminating antibiotic-resistant bacteria with a high degree of host adaptation.
Promotion of acceptor formation in SnO2 nanowires by e-beam bombardment and impacts to sensor application
Authors: Sub Kim Sang , Gil Na Han , Woo Kim Hyoun , Kulish Vadym , Wu Ping
Published: June 2015

We have realized a p-type-like conduction in initially n-type SnO2 nanowires grown using a vapor-liquid-solid method. The transition was achieved by irradiating n-type SnO2 nanowires with a high-energy electron beam, without intentional chemical doping. The nanowires were irradiated at doses of 50 and 150 kGy and were then used to fabricate NO2 gas sensors, which exhibited n-type and p-type conductivities, respectively. The tuneability of the conduction behavior is assumed to be governed by the formation of tin vacancies (under high-energy electron beam irradiation), because it is the only possible acceptor, excluding all possible defects via density functional theory (DFT) calculations. The effect of external electric fields on the defect stability was studied using DFT calculations. The measured NO2 sensing dynamics, including response and recovery times, were well represented by the electron-hole compensation mechanism from standard electron-hole gas equilibrium statistics. This study elucidates the charge-transport characteristics of bipolar semiconductors that underlie surface chemical reactions. The principles derived will guide the development of future SnO2-based electronic and electrochemical devices.
Electroretinographic assessment of rod- and cone-mediated bipolar cell pathways using flicker stimuli in mice
Authors: Tanimoto Naoyuki , Sothilingam Vithiyanjali , Kondo Mineo , Biel Martin , Humphries Peter , Seeliger Mathias W.
Published: June 2015

Mouse full-field electroretinograms (ERGs) are dominated by responses of photoreceptors and depolarizing (ON-) bipolar cells, but not much of hyperpolarizing (OFF-) bipolar cells under conventional recording conditions. Here we investigate a novel ERG protocol in mice for functional assessment of the major ON- and OFF-bipolar cell pathways using flicker stimuli for a high luminance with varying frequency up to 30 Hz. Wild-type (WT) and functionally specific transgenic mice (Cnga3-/-, no cone photoreceptor function; rho-/-, no rod photoreceptor function; mGluR6-/-, no ON-bipolar cell function) were examined. The Cnga3-/- flicker ERG was similar to the WT flicker ERG at very low stimulus frequencies, whereas ERGs were comparable between WT and rho-/- mice at 5 Hz and above. Between 5 and 15 Hz, ERGs in mGluR6-/- mice differed in configuration and amplitude from those in WT and rho-/- mice; in contrast, response amplitudes above 15 Hz were comparable among WT, rho-/- and mGluR6-/- mice. In summary, we found three frequency ranges with these conditions that are dominated by activity in the rod pathways (below 5 Hz), cone ON-pathway (between 5 and 15 Hz) and cone OFF-pathway (above 15 Hz) that enables a quick overview of the functionality of the major bipolar cell pathways.
Automated Pipeline for Purification, Biophysical and X-Ray Analysis of Biomacromolecular Solutions
Authors: Graewert Melissa A. , Franke Daniel , Jeffries Cy M. , Blanchet Clement E. , Ruskule Darja , Kuhle Katja , Flieger Antje , Schäfer Bernd , Tartsch Bernd , Meijers Rob , Svergun Dmitri I.
Published: June 2015

Small angle X-ray scattering (SAXS), an increasingly popular method for structural analysis of biological macromolecules in solution, is often hampered by inherent sample polydispersity. We developed an all-in-one system combining in-line sample component separation with parallel biophysical and SAXS characterization of the separated components. The system coupled to an automated data analysis pipeline provides a novel tool to study difficult samples at the P12 synchrotron beamline (PETRA-3, EMBL/DESY, Hamburg).
Some like it hot: Thermal tolerance and oxygen supply capacity in two eurythermal crustaceans
Authors: Ern Rasmus , Huong Do Thi Thanh , Phuong Nguyen Thanh , Madsen Peter Teglberg , Wang Tobias , Bayley Mark
Published: June 2015

Thermal sensitivity of the cardiorespiratory oxygen supply capacity has been proposed as the cardinal link underlying the upper boundary of the temperature niche in aquatic ectotherms. Here we examined the evidence for this link in two eurythermal decapods, the Giant tiger shrimp (Penaeus monodon) and the European crayfish (Astacus astacus). We found that both species have a temperature resistant cardiorespiratory system, capable of maintaining oxygen delivery up to their upper critical temperature (Tcrit). In neither species was Tcrit reduced in hypoxia (60% air saturation) and both species showed an exponential increase in heart and gill ventilation rates up to their Tcrit. Further, failure of action potential conduction in preparations of A. astacus motor neurons coincided with Tcrit, indicating that compromised nervous function may provide the underlying determinant for Tcrit rather than oxygen delivery. At high temperatures, absolute aerobic scope was maintained in P. monodon, but reduced in A. astacus. However, A. astacus also displayed reduced exercise intensity indicating that impaired muscle performance with resulting reduced tissue oxygen demand may explain the reduced scope rather than insufficient oxygen supply capacity. This interpretation agrees with early literature on aquatic ectotherms, correlating loss of nervous function with impaired locomotion as temperatures approach Tcrit.
Effect of dilution of stool soluble component on growth and development of Strongyloides stercoralis
Authors: Anamnart Witthaya , Maleewong Intapan Pewpan , Pattanawongsa Attarat , Chamavit Pennapa , Kaewsawat Supreecha , Maleewong Wanchai
Published: June 2015

Dispersion or dilution of stool by water from heavy rainfall may affect Strongyloides stercoralis free-living development producing infective filariform larvae (FL). This study examined effect of water dilution of stool on survival of S. stercoralis free-living development. One g of stool was prepared in water so that its soluble component was diluted sequentially from 1:2 to 1:480. Three dishes were used to compare FL production in three culture conditions: stool suspension, stool sediment deposited in soil and isolated rhabditiform larvae (RhL) deposited in soil. The fourth dish was for developmental observation of RhL into free-living stages. Numerous FL were generated from undiluted or 1:2 diluted stool and stool sediment placed on soil. However, starting from dilution 1:5, FL production continuously decreased in both stool suspensions and stool sediments placed on soil. RhL isolated from stool dilutions placed on soil gave rise to few FL. Worm mating were seen at 24-30 hours in dilutions 1:20-1:120 only. Highest numbers of FL from indirect free-living cycle were 1/3 of those from control. FL production decreased as stool dilution increased and reached zero production at 1:160 dilution. Rainfall may disperse or dilute stool so that nutritional supplement for S. stercoralis free-living development is insufficient.
Discovery of novel inhibitors of human S-adenosylmethionine decarboxylase based on in silico high-throughput screening and a non-radioactive enzymatic assay
Authors: Liao Chenzeng , Wang Yanlin , Tan Xiao , Sun Lidan , Liu Sen
Published: June 2015

Natural polyamines are small polycationic molecules essential for cell growth and development and elevated level of polyamines is positively correlated with various cancers. As a rate-limiting enzyme of the polyamine biosynthetic pathway, S-adenosylmethionine decarboxylase (AdoMetDC) has been an attractive drug target. In this report, we present the discovery of novel human AdoMetDC (hAdoMetDC) inhibitors by coupling computational and experimental tools. We constructed a reasonable computational structure model of hAdoMetDC that is compatible with general protocols for high-throughput drug screening and used this model inin silicoscreening of hAdoMetDC inhibitors against a large compound library using a battery of computational tools. We also established and validated a simple, economic and non-radioactive enzymatic assay, which can be adapted for experimental high-throughput screening of hAdoMetDC inhibitors. Finally, we obtained an hAdoMetDC inhibitor lead with a novel scaffold. This study provides both new tools and a new lead for the developing of novel hAdoMetDC inhibitors.
Hemocompatibility improvement of perfusion-decellularized clinical-scale liver scaffold through heparin immobilization
Authors: Bao Ji , Wu Qiong , Sun Jiu , Zhou Yongjie , Wang Yujia , Jiang Xin , Li Li , Shi Yujun , Bu Hong
Published: June 2015

Whole-liver perfusion-decellularization is an attractive scaffold–preparation technique for producing clinical transplantable liver tissue. However, the scaffold’s poor hemocompatibility poses a major obstacle. This study was intended to improve the hemocompatibility of perfusion-decellularized porcine liver scaffold via immobilization of heparin. Heparin was immobilized on decellularized liver scaffolds (DLSs) by electrostatic binding using a layer-by-layer self-assembly technique (/h-LBL scaffold), covalent binding via multi-point attachment (/h-MPA scaffold), or end-point attachment (/h-EPA scaffold). The effect of heparinization on anticoagulant ability and cytocompatibility were investigated. The result of heparin content and release tests revealed EPA technique performed higher efficiency of heparin immobilization than other two methods. Then, systematic in vitro investigation of prothrombin time (PT), thrombin time (TT), activated partial thromboplastin time (APTT), platelet adhesion and human platelet factor 4 (PF4, indicates platelet activation) confirmed the heparinized scaffolds, especially the /h-EPA counterparts, exhibited ultralow blood component activations and excellent hemocompatibility. Furthermore, heparin treatments prevented thrombosis successfully in DLSs with blood perfusion after implanted in vivo. Meanwhile, after heparin processes, both primary hepatocyte and endothelial cell viability were also well-maintained, which indicated that heparin treatments with improved biocompatibility might extend to various hemoperfusable whole-organ scaffolds’ preparation.
Catalytic subunits of the phosphatase calcineurin interact with NF-κB-inducing kinase (NIK) and attenuate NIK-dependent gene expression
Authors: Shinzawa Miho , Konno Hiroyasu , Qin Junwen , Akiyama Nobuko , Miyauchi Maki , Ohashi Hiroyuki , Miyamoto-Sato Etsuko , Yanagawa Hiroshi , Akiyama Taishin , Inoue Jun-ichiro
Published: June 2015

Nuclear factor (NF)-κB-inducing kinase (NIK) is a serine/threonine kinase that activates NF-κB pathways, thereby regulating a wide variety of immune systems. Aberrant NIK activation causes tumor malignancy, suggesting a requirement for precise regulation of NIK activity. To explore novel interacting proteins of NIK, we performed in vitro virus screening and identified the catalytic subunit Aα isoform of serine/threonine phosphatase calcineurin (CnAα) as a novel NIK-interacting protein. The interaction of NIK with CnAα in living cells was confirmed by co-immunoprecipitation. Calcineurin catalytic subunit Aβ isoform (CnAβ) also bound to NIK. Experiments using domain deletion mutants suggested that CnAα and CnAβ interact with both the kinase domain and C-terminal region of NIK. Moreover, the phosphatase domain of CnAα is responsible for the interaction with NIK. Intriguingly, we found that TRAF3, a critical regulator of NIK activity, also binds to CnAα and CnAβ. Depletion of CnAα and CnAβ significantly enhanced lymphotoxin-β receptor (LtβR)-mediated expression of the NIK-dependent gene Spi-B and activation of RelA and RelB, suggesting that CnAα and CnAβ attenuate NF-κB activation mediated by LtβR-NIK signaling. Overall, these findings suggest a possible role of CnAα and CnAβ in modifying NIK functions.
Oxalic acid and sclerotial differentiation of Polyporus umbellatus
Authors: Xing Yong-Mei , Yin Wan-Qiang , Liu Meng-Meng , Wang Chun-Lan , Guo Shun-Xing
Published: June 2015

The present investigation aimed to uncover the effects of exogenous oxalic acid during the sclerotial formation of Polyporus umbellatus, with an emphasis on determining the content of the endogenic oxalic acid in the fungus. To this end, the oxalic acid content of the vegetative mycelia, sclerotia, culture mediums and sclerotial exudate were measured using High Performance Liquid Chromatography (HPLC). Furthermore, the lipid peroxidation was estimated by detecting thiobarbituric bituric acid reactive substances (TBARS). The results showed that the exogenous oxalic acid caused a delay in sclerotial differentiation (of up to 9 or more days), suppressed the sclerotial biomass and decreased the lipid peroxidation significantly in a concentration-dependent manner. Oxalic acid was found at very low levels in the mycelia and the maltose medium, whereas it was found at high levels in the mycelia and sucrose medium. After sclerotial differentiation, oxalic acid accumulated at high levels in both the sclerotia and the sclerotial exudate. Oxalic acid was therefore found to inhibit P. umbellatus sclerotial formation.
Unraveling the molecular architecture of a G protein-coupled receptor/β-arrestin/Erk module complex
Authors: Bourquard Thomas , Landomiel Flavie , Reiter Eric , Crépieux Pascale , Ritchie David W. , Azé Jérôme , Poupon Anne
Published: June 2015

β-arrestins serve as signaling scaffolds downstream of G protein-coupled receptors and thus play a crucial role in a plethora of cellular processes. Although it is largely accepted that the ability of β-arrestins to interact simultaneously with many protein partners is key in G protein-independent signaling of GPCRs, only the precise knowledge of these multimeric arrangements will allow a full understanding of the dynamics of these interactions and their functional consequences. However, current experimental procedures for the determination of the three-dimensional structures of protein-protein complexes are not well adapted to analyze these short-lived, multi-component assemblies. We propose a model of the receptor/β-arrestin/Erk1 signaling module, which is consistent with most of the available experimental data. Moreover, for the β-arrestin/Raf1 and the β-arrestin/ERK interactions, we have used the model to design interfering peptides and shown that they compete with both partners, hereby demonstrating the validity of the predicted interaction regions.
Burkholderia cenocepacia and Salmonella enterica ArnT proteins that transfer 4-amino-4-deoxy-l-arabinose to lipopolysaccharide share membrane topology and functional amino acids
Authors: Tavares-Carreón Faviola , Patel Kinnari B. , Valvano Miguel A.
Published: June 2015

We recently demonstrated that incorporation of 4-amino-4-deoxy-l-arabinose (l-Ara4N) to the lipid A moiety of lipopolysaccharide (LPS) is required for transport of LPS to the outer membrane and viability of the Gram-negative bacterium Burkholderia cenocepacia. ArnT is a membrane protein catalyzing the transfer of l-Ara4N to the LPS molecule at the periplasmic face of the inner membrane, but its topology and mechanism of action are not well characterized. Here, we elucidate the topology of ArnT and identify key amino acids that likely contribute to its enzymatic function. PEGylation assays using a cysteineless version of ArnT support a model of 13 transmembrane helices and a large C-terminal region exposed to the periplasm. The same topological configuration is proposed for the Salmonella enterica serovar Typhimurium ArnT. Four highly conserved periplasmic residues in B. cenocepacia ArnT, tyrosine-43, lysine-69, arginine-254 and glutamic acid-493, were required for activity. Tyrosine-43 and lysine-69 span two highly conserved motifs, 42RYA44 and 66YFEKP70, that are found in ArnT homologues from other species. The same residues in S. enterica ArnT are also needed for function. We propose these aromatic and charged amino acids participate in either undecaprenyl phosphate-l-Ara4N substrate recognition or transfer of l-Ara4N to the LPS.
Effect of N2 and H2 plasma treatments on band edge emission of ZnO microrods
Authors: Rodrigues Joana , Holz Tiago , Fath Allah Rabie , Gonzalez David , Ben Teresa , Correia Maria R. , Monteiro Teresa , Costa Florinda M.
Published: June 2015

ZnO microrods were grown by laser assisted flow deposition technique in order to study their luminescence behaviour in the near band edge spectral region. Transmission electron microscopy analysis put in evidence the high crystallinity degree and microrod’s compositional homogeneity. Photoluminescence revealed a dominant 3.31 eV emission. The correlation between this emission and the presence of surface states was investigated by performing plasma treatments with hydrogen and nitrogen. The significant modifications in photoluminescence spectra after the plasma treatments suggest a connexion between the 3.31 eV luminescence and the surface related electronic levels.
Gross primary production of global forest ecosystems has been overestimated
Authors: Ma Jianyong , Yan Xiaodong , Dong Wenjie , Chou Jieming
Published: June 2015

Coverage rate, a critical variable for gridded forest area, has been neglected by previous studies in estimating the annual gross primary production (GPP) of global forest ecosystems. In this study, we investigated to what extent the coverage rate could impact forest GPP estimates from 1982 to 2011. Here we show that the traditional calculation without considering the coverage rate globally overestimated the forest gross carbon dioxide uptake by approximately 8.7%, with a value of 5.12 ± 0.23 Pg C yr−1, which is equivalent to 48% of the annual emissions from anthropogenic activities in 2012. Actually, the global annual GPP of forest ecosystems is approximately 53.71 ± 4.83 Pg C yr−1 for the past 30 years by taking the coverage rate into account. Accordingly, we argue that forest annual GPP calculated by previous studies has been overestimated due to the exaggerated forest area and therefore, coverage rate may be a required factor to further quantify the global carbon cycle.
Nontoxic singlet oxygen generator as a therapeutic candidate for treating tauopathies
Authors: Sheik Mohideen Sahabudeen , Yamasaki Yasutoyo , Omata Yasuhiro , Tsuda Leo , Yoshiike Yuji
Published: June 2015

Methylene blue (MB) inhibits the aggregation of tau, a main constituent of neurofibrillary tangles. However, MB’s mode of action in vivo is not fully understood. MB treatment reduced the amount of sarkosyl-insoluble tau in Drosophila that express human wild-type tau. MB concurrently ameliorated the climbing deficits of transgenic tau flies to a limited extent and diminished the climbing activity of wild-type flies. MB also decreased the survival rate of wild-type flies. Based on its photosensitive efficacies, we surmised that singlet oxygen generated through MB under light might contribute to both the beneficial and toxic effects of MB in vivo. We identified rose bengal (RB) that suppressed tau accumulation and ameliorated the behavioral deficits to a lesser extent than MB. Unlike MB, RB did not reduce the survival rate of flies. Our findings indicate that singlet oxygen generators with little toxicity may be suitable drug candidates for treating tauopathies.
Projection of corn production and stover-harvesting impacts on soil organic carbon dynamics in the U.S. Temperate Prairies
Authors: Wu Yiping , Liu Shuguang , Young Claudia J. , Dahal Devendra , Sohl Terry L. , Davis Brian
Published: June 2015

Terrestrial carbon sequestration potential is widely considered as a realistic option for mitigating greenhouse gas emissions. However, this potential may be threatened by global changes including climate, land use and management changes such as increased corn stover harvesting for rising production of cellulosic biofuel. Therefore, it is critical to investigate the dynamics of soil organic carbon (SOC) at regional or global scale. This study simulated the corn production and spatiotemporal changes of SOC in the U.S. Temperate Prairies, which covers over one-third of the U.S. corn acreage, using a biogeochemical model with multiple climate and land-use change projections. The corn production (either grain yield or stover biomass) could reach 88.7–104.7 TgC as of 2050, 70–101% increase when compared to the base year of 2010. A removal of 50% stover at the regional scale could be a reasonable cap in view of maintaining SOC content and soil fertility especially in the beginning years. The projected SOC dynamics indicated that the average carbon sequestration potential across the entire region may vary from 12.7 to 19.6 g C/m2/yr (i.e., 6.6–10.2 g TgC/yr). This study not only helps understand SOC dynamics but also provides decision support for sustainable biofuel development.
A Novel Direct Factor Xa Inhibitory Peptide with Anti-Platelet Aggregation Activity from Agkistrodon acutus Venom Hydrolysates
Authors: Chen Meimei , Ye Xiaohui , Ming Xin , Chen Yahui , Wang Ying , Su Xingli , Su Wen , Kong Yi
Published: June 2015

Snake venom is a natural substance that contains numerous bioactive proteins and peptides, nearly all of which have been identified over the last several decades. In this study, we subjected snake venom to enzymatic hydrolysis to identify previously unreported bioactive peptides. The novel peptide ACH-11 with the sequence LTFPRIVFVLG was identified with both FXa inhibition and anti-platelet aggregation activities. ACH-11 inhibited the catalytic function of FXa towards its substrate S-2222 via a mixed model with a Ki value of 9.02 μM and inhibited platelet aggregation induced by ADP and U46619 in a dose-dependent manner. Furthermore, ACH-11 exhibited potent antithrombotic activity in vivo. It reduced paralysis and death in an acute pulmonary thrombosis model by 90% and attenuated thrombosis weight in an arterio-venous shunt thrombosis model by 57.91%, both at a dose of 3 mg/kg. Additionally, a tail cutting bleeding time assay revealed that ACH-11 did not prolong bleeding time in mice at a dose of 3 mg/kg. Together, our results reveal that ACH-11 is a novel antithrombotic peptide exhibiting both FXa inhibition and anti-platelet aggregation activities, with a low bleeding risk. We believe that it could be a candidate or lead compound for new antithrombotic drug development.
Learning about Sustainable Development in Socio-Scientific Issues-Based Chemistry Lessons on Fuels and Bioplastics
Authors: Mamlok-Naaman Rachel , Katchevich Dvora , Yayon Malka , Burmeister Mareike , Feierabend Timo , Eilks Ingo
Published: June 2015

This chapter discusses the application of socio-scientific issues (SSI)-based science education in the secondary chemistry classroom. Issues of sustainable development are suggested to contextualize chemistry learning. If this is operated in an SSI-based approach controversial issues from the sustainability debate are used to motivate chemistry learning under thorough inclusion of a societal perspective. Apart from chemistry content learning the lessons focus on an understanding of how society is dealing with developments in chemistry and technology. Examples will be presented from secondary chemistry teaching in Israel and Germany. Alternative fuels and bioplastics will serve as examples. The discussion will show that a combination of SSI-based science teaching with issues of sustainable development offers a fruitful approach to motivate chemistry learning and contribute to the development of general educational skills.
Collaborative Development of a High School Green Chemistry Curriculum in Thailand
Authors: Doxsee Kenneth M.
Published: June 2015

Green chemistry represents an ideal platform for the chemistry teaching laboratory, introducing students to fundamental laboratory techniques while engaging them with the latest developments in chemistry and our understanding of its relationship to human health and the environment. By combining the intrinsic safety of green chemistry with experimentation that draws from locally available resources, we can provide universal access to experimental chemistry, allowing students everywhere the opportunity to benefit from the powerful learning environment of the laboratory. Having developed and presented a set of internet-based workshops for Thai high school science teachers, we are now actively involved in the creation of a green curriculum in collaboration with teachers and administrators at Assumption College, Thonburi. In addition to presenting an overview of these curricular developments, this chapter addresses the ways in which various challenges have been converted into new opportunities, as well as other issues that should prove of general interest and utility to educators seeking to develop and implement similar curricular reforms.
Green Catalysts for Producing Liquid Fuels from Lignocellulosic Biomass
Authors: Xiao Dequan , Beach Evan S.
Published: June 2015

In accordance with the goals of green chemistry, lignocellulose (or non-food) biomass is increasingly recognized as a valuable renewable energy resource. Converting biomass into liquid fuels will not only help to reduce our dependence on petroleum, but will also alleviate CO2 emissions. Designing effective, low-cost, robust, and sustainable biomass catalysts is an indispensable step for developing the next generation technologies of converting lignocellulose biomass to liquid fuels. In this chapter, we focus on current efforts to apply various catalysts in the conversion of lignocellulosic biomass polymers into liquid fuels. From the viewpoint of the fundamental chemistry, we categorize the current biomass conversion methods into three paths, and then discuss the main chemical processes and reaction mechanisms for specific biomass conversion methods, as well as the typical catalysts that are used. Since these biomass catalysts are used to perform green chemistry (i.e., producing renewable energy), we also call them green catalysts. We hope that this chapter will serve as a tutorial for green chemistry education, and inspire researchers to design more efficient, robust, low-cost, and sustainable catalytic approaches for biomass conversion.
The State of Green Chemistry Instruction at Canadian Universities
Authors: Andraos John , Dicks Andrew P.
Published: June 2015

This chapter summarizes some of the important green chemistry teaching initiatives currently in place at the Canadian post-secondary education level. It presents examples taken from several Canadian universities currently offering undergraduate courses and/or laboratory instruction involving green principles. Relevant syllabi are compared and contrasted to provide a perspective on what is being taught and how, along with materials published by authors at Canadian institutions in the field of green chemistry education. Student and instructor feedback is additionally provided as appropriate. Potential future directions in green chemistry are also discussed.
Green Chemistry Education in Russia
Authors: Tarasova Natalia , Lokteva Ekaterina , Lunin Valery
Published: June 2015

The great need for sustainable and green chemistry education (GCE) in Russia is confirmed by the data of public-opinion polls and reflected in the actions of the authorities. However, these concept and approach are not widely and deeply familiar to the general public and even specialists, so great effort in this direction is needed. The characteristic features of GCE in Russia are determined by the diversity in the economic situation in different regions. The main providers of GCE at all levels (secondary school, university and PhD school, professional training, and enlightenment of general public) are Russian universities in close cooperation with research institutions, including the formation of Scientific-Educational Centers. In this chapter the mosaic of GCE in Russia is presented based on the activities of D. Mendeleev University of Chemical Technology of Russia, Lomonosov Moscow State University, Gubkin University of Oil and Gas, as well as federal and state universities located in different parts of Russia, namely Arkhangelsk, Novosibirsk, Krasnoyarsk, Kursk, Astrakhan, Kazan, etc.
Introducing Green Chemistry into Graduate Courses at the Brazilian Green Chemistry School
Authors: Seidl Peter R. , Freire Estevão , Borschiver Suzana , Leite L. F.
Published: June 2015

The Brazilian Green Chemistry School was established with well-defined purposes. Among them are projects to raise the competitivity of local industry through innovation in processes and products based on renewable starting materials. Thus new courses that are being designed for the school must provide basic knowledge of green chemistry as well as of the tools that are used to compare different alternatives and evaluate their chances of success. Brazil has a unique position as a tropical country with regions that face problems common to developing countries, as well as large and highly industrialized sectors of the economy that suffer from lack of international competitivity. The Graduate Program on Chemical and Biochemical Processes at the Federal University of Rio de Janeiro was chosen as a base for the school and began introducing the new courses in 2012. We believe that our experience in preparing green chemistry courses that address local needs may be of interest to colleagues who work on similar initiatives or plan to do so in the near future.
Heterologous expression of the avirulence gene ACE1 from the fungal rice pathogen Magnaporthe oryzae
Authors: Song Zhongshu , Bakeer Walid , Marshall James W. , Yakasai Ahmed A. , Khalid Rozida Mohd , Collemare Jerome , Skellam Elizabeth , Tharreau Didier , Lebrun Marc-Henri , Lazarus Colin M. , Bailey Andrew M. , Simpson Thomas J. , Cox Russell J.
Published: June 2015

Heterologous expression of key components of the Magnaporthe grisea ACE1 gene cluster produces a potential precursor of cryptic avirulence signalling compounds that induce resistance to M. grisea in rice.
Fluorescent and colorimetric sensors for environmental mercury detection
Authors: Chen Guiqiu , Guo Zhi , Zeng Guangming , Tang Lin
Published: June 2015

The development of fluorescent and colorimetric sensing strategies for environmental mercury is described.
CuFe2O4 magnetic nanocrystal clusters as a matrix for the analysis of small molecules by negative-ion matrix-assisted laser desorption/ionization time-of-flight mass spectrometry
Authors: Lin Zian , Zheng Jiangnan , Bian Wei , Cai Zongwei
Published: June 2015

CuFe2O4 MNCs were proposed as a new matrix for negative ion MALDI-TOF MS, which exhibited interference-free background, high salt tolerance and good reproducibility for analysis of small molecules.
Profiling of aldehyde-containing compounds by stable isotope labelling-assisted mass spectrometry analysis
Authors: Yu Lei , Liu Ping , Wang Ya-Lan , Yu Qiong-Wei , Yuan Bi-Feng , Feng Yu-Qi
Published: June 2015

A SIL–LC–DNLS–MS strategy for profiling of aldehyde-containing compounds is presented.
A single-molecule digital enzyme assay using alkaline phosphatase with a cumarin-based fluorogenic substrate
Authors: Obayashi Yusuke , Iino Ryota , Noji Hiroyuki
Published: June 2015

Digitalization of fluorogenic enzymatic assays through the use of femtoliter chamber array technology is an emerging approach to realizing highly quantitative bioassays with single-molecule sensitivity.
A biomimetic mussel-inspired photoelectrochemical biosensing chip for the sensitive detection of CD146
Authors: Ma Hongmin , Yan Tao , Zhang Yong , Gao Picheng , Pang Xuehui , Du Bin , Wei Qin
Published: June 2015

A universal biomimetic mussel-inspired photoelectrochemical biosensing chip was constructed by a polydopamine coating strategy.
Ethylenediamine-functionalized superparamagnetic carbon nanotubes for magnetic molecularly imprinted polymer matrix solid-phase dispersion extraction of 12 fluoroquinolones in river water
Authors: Chen Xiao-Hong , Zhao Yong-Gang , Zhang Yun , Shen Hao-Yu , Pan Sheng-Dong , Jin Mi-Cong
Published: June 2015

A novel fluoroquinolone molecularly imprinted polymer (MIP) on the surface of ethylenediamine-functionalized magnetic carbon nanotubes (EDA@Mag-CNTs–MIP) was synthesised.
A catechin-modified carbon paste electrode for electrocatalytic determination of neurotransmitters
Authors: Wei Juan , He Jianbo , Chen Changlun , Wang Xiangke
Published: June 2015

Catechin was electropolymerized on an activated carbon paste electrode for electrocatalytic determination of dopamine and serotonin.