bluuebunny/crossref_metadata_2025 huggingface dataset:
Dexras1 links glucocorticoids to insulin-like growth factor-1 signaling in adipogenesis
Authors: Kim Hyo Jung , Cha Jiyoung Y. , Seok Jo Woon , Choi Yoonjeong , Yoon Bo Kyung , Choi Hyeonjin , Yu Jung Hwan , Song Su Jin , Kim Ara , Lee Hyemin , Kim Daeun , Han Ji Yoon , Kim Jae-woo
Published: June 2016

Glucocorticoids are associated with obesity, but the underlying mechanism by which they function remains poorly understood. Previously, we showed that small G protein Dexras1 is expressed by glucocorticoids and leads to adipocyte differentiation. In this study, we explored the mechanism by which Dexras1 mediates adipogenesis and show a link to the insulin-like growth factor-1 (IGF-1) signaling pathway. Without Dexras1, the activation of MAPK and subsequent phosphorylation of CCAAT/enhancer binding protein β (C/EBPβ) is abolished, thereby inhibiting mitotic clonal expansion and further adipocyte differentiation. Dexras1 translocates to the plasma membrane upon insulin or IGF-1 treatment, for which the unique C-terminal domain (amino acids 223–276) is essential. Dexras1-dependent MAPK activation is selectively involved in the IGF-1 signaling, because another Ras protein, H-ras localized to the plasma membrane independently of insulin treatment. Moreover, neither epidermal growth factor nor other cell types shows Dexras1-dependent MAPK activation, indicating the importance of Dexras1 in IGF-1 signaling in adipogenesis. Dexras1 interacts with Shc and Raf, indicating that Dexras1-induced activation of MAPK is largely dependent on the Shc-Grb2-Raf complex. These results suggest that Dexras1 is a critical mediator of the IGF-1 signal to activate MAPK, linking glucocorticoid signaling to IGF-1 signaling in adipogenesis.
Twin-mediated crystal growth: an enigma resolved
Authors: Shahani Ashwin J. , Gulsoy E. Begum , Poulsen Stefan O. , Xiao Xianghui , Voorhees Peter W.
Published: June 2016

During crystal growth, faceted interfaces may be perturbed by defects, leading to a rich variety of polycrystalline growth forms. One such defect is the coherent Σ3 {111} twin boundary, which is widely known to catalyze crystal growth. These defects have a profound effect on the properties of many materials: for example, electron-hole recombination rates strongly depend on the character of the twin boundaries in polycrystalline Si photovoltaic cells. However, the morphology of the twinned interface during growth has long been a mystery due to the lack of four-dimensional (i.e., space and time resolved) experiments. Many controversial mechanisms have been proposed for this process, most of which lack experimental verification. Here, we probe the real-time interfacial dynamics of polycrystalline Si particles growing from an Al-Si-Cu liquid via synchrotron-based X-ray tomography. Our novel analysis of the time evolution of the interfacial normals allows us to quantify unambiguously the habit plane and grain boundary orientations during growth. This, when combined with direct measurements of the interfacial morphology provide the first confirmation of twin-mediated growth, proposed over 50 years ago. Using the insights provided by these experiments, we have developed a unified picture of the phenomena responsible for the dynamics of faceted Si growth.
Comparative Structural and Computational Analysis Supports Eighteen Cellulose Synthases in the Plant Cellulose Synthesis Complex
Authors: Nixon B. Tracy , Mansouri Katayoun , Singh Abhishek , Du Juan , Davis Jonathan K. , Lee Jung-Goo , Slabaugh Erin , Vandavasi Venu Gopal , O’Neill Hugh , Roberts Eric M. , Roberts Alison W. , Yingling Yaroslava G. , Haigler Candace H.
Published: June 2016

A six-lobed membrane spanning cellulose synthesis complex (CSC) containing multiple cellulose synthase (CESA) glycosyltransferases mediates cellulose microfibril formation. The number of CESAs in the CSC has been debated for decades in light of changing estimates of the diameter of the smallest microfibril formed from the β-1,4 glucan chains synthesized by one CSC. We obtained more direct evidence through generating improved transmission electron microscopy (TEM) images and image averages of the rosette-type CSC, revealing the frequent triangularity and average cross-sectional area in the plasma membrane of its individual lobes. Trimeric oligomers of two alternative CESA computational models corresponded well with individual lobe geometry. A six-fold assembly of the trimeric computational oligomer had the lowest potential energy per monomer and was consistent with rosette CSC morphology. Negative stain TEM and image averaging showed the triangularity of a recombinant CESA cytosolic domain, consistent with previous modeling of its trimeric nature from small angle scattering (SAXS) data. Six trimeric SAXS models nearly filled the space below an average FF-TEM image of the rosette CSC. In summary, the multifaceted data support a rosette CSC with 18 CESAs that mediates the synthesis of a fundamental microfibril composed of 18 glucan chains.
Neuroprotection mediated by inhibition of calpain during acute viral encephalitis
Authors: Howe Charles L. , LaFrance-Corey Reghann G. , Mirchia Kanish , Sauer Brian M. , McGovern Renee M. , Reid Joel M. , Buenz Eric J.
Published: June 2016

Neurologic complications associated with viral encephalitis, including seizures and cognitive impairment, are a global health issue, especially in children. We previously showed that hippocampal injury during acute picornavirus infection in mice is associated with calpain activation and is the result of neuronal death triggered by brain-infiltrating inflammatory monocytes. We therefore hypothesized that treatment with a calpain inhibitor would protect neurons from immune-mediated bystander injury. C57BL/6J mice infected with the Daniel’s strain of Theiler’s murine encephalomyelitis virus were treated with the FDA-approved drug ritonavir using a dosing regimen that resulted in plasma concentrations within the therapeutic range for calpain inhibition. Ritonavir treatment significantly reduced calpain activity in the hippocampus, protected hippocampal neurons from death, preserved cognitive performance and suppressed seizure escalation, even when therapy was initiated 36 hours after disease onset. Calpain inhibition by ritonavir may be a powerful tool for preserving neurons and cognitive function and preventing neural circuit dysregulation in humans with neuroinflammatory disorders.
Increased Endothelial Progenitor Cell Levels are Associated with Good Outcome in Intracerebral Hemorrhage
Authors: Pías-Peleteiro Juan , Pérez-Mato María , López-Arias Esteban , Rodríguez-Yáñez Manuel , Blanco Miguel , Campos Francisco , Castillo José , Sobrino Tomás
Published: June 2016

Circulating endothelial progenitor cells (EPCs) play a role in the regeneration of damaged brain tissue. However, the relationship between circulating EPC levels and functional recovery in intracerebral hemorrhage (ICH) has not yet been tested. Therefore, our aim was to study the influence of circulating EPCs on the outcome of ICH. Forty-six patients with primary ICH (males, 71.7%; age, 72.7 ± 10.8 years) were prospectively included in the study within 12 hours of symptom onset. The main outcome variable was good functional outcome at 12 months (modified Rankin scale ≤2), considering residual volume at 6 months as a secondary variable. Circulating EPC (CD34+/CD133+/KDR+) levels were measured by flow cytometry from blood samples obtained at admission, 72 hours and day 7. Our results indicate that patients with good outcome show higher EPC numbers at 72 hours and day 7 (all p < 0.001). However, only EPC levels at day 7 were independently associated with good functional outcome at 12 months (OR, 1.15; CI95%, 1.01–1.35) after adjustment by age, baseline stroke severity and ICH volume. Moreover, EPC levels at day 7 were negatively correlated to residual volume (r = −0.525; p = 0.005). In conclusion, these findings suggest that EPCs may play a role in the functional recovery of ICH patients.
Inverse spin Hall effect in a complex ferromagnetic oxide heterostructure
Authors: Wahler Martin , Homonnay Nico , Richter Tim , Müller Alexander , Eisenschmidt Christian , Fuhrmann Bodo , Schmidt Georg
Published: June 2016

We present spin pumping and inverse spin Hall effect (ISHE) in an epitaxial complex oxide heterostructure. Ferromagnetic La0.7Sr0.3MnO3 (LSMO) is used as a source of spin pumping while the spin sink exhibiting the ISHE consists of SrRuO3 (SRO). SRO is a ferromagnetic oxide with metallic conductivity, however, with a Curie temperature (TC) of 155 K, thus well below room temperature. This choice allows to perform the experiment above and below TC of the SRO and to demonstrate that SRO not only shows an ISHE of a magnitude comparable to Pt (though with opposite sign) in its non magnetic state but also exhibits a finite ISHE even 50 K below TC.
Enhanced four-wave mixing with nonlinear plasmonic metasurfaces
Authors: Jin Boyuan , Argyropoulos Christos
Published: June 2016

Plasmonic metasurfaces provide an effective way to increase the efficiency of several nonlinear processes while maintaining nanoscale dimensions. In this work, nonlinear metasurfaces based on film-coupled silver nanostripes loaded with Kerr nonlinear material are proposed to achieve efficient four-wave mixing (FWM). Highly localized plasmon resonances are formed in the nanogap between the metallic film and nanostripes. The local electric field is dramatically enhanced in this subwavelength nanoregion. These properties combined with the relaxed phase matching condition due to the ultrathin area lead to a giant FWM efficiency, which is enhanced by nineteen orders of magnitude compared to a bare silver screen. In addition, efficient visible and low-THz sources can be constructed based on the proposed nonlinear metasurfaces. The FWM generated coherent wave has a directional radiation pattern and its output power is relatively insensitive to the incident angles of the excitation sources. This radiated power can be further enhanced by increasing the excitation power. The dielectric nonlinear material placed in the nanogap is mainly responsible for the ultrastrong FWM response. Compact and efficient wave mixers and optical sources spanning different frequency ranges are envisioned to be designed based on the proposed nonlinear metasurface designs.
Crosstalk between cellular compartments protects against proteotoxicity and extends lifespan
Authors: Perić Matea , Dib Peter Bou , Dennerlein Sven , Musa Marina , Rudan Marina , Lovrić Anita , Nikolić Andrea , Šarić Ana , Sobočanec Sandra , Mačak Željka , Raimundo Nuno , Kriško Anita
Published: June 2016

In cells living under optimal conditions, protein folding defects are usually prevented by the action of chaperones. Here, we investigate the cell-wide consequences of loss of chaperone function in cytosol, mitochondria or the endoplasmic reticulum (ER) in budding yeast. We find that the decline in chaperone activity in each compartment results in loss of respiration, demonstrating the dependence of mitochondrial activity on cell-wide proteostasis. Furthermore, each chaperone deficiency triggers a response, presumably via the communication among the folding environments of distinct cellular compartments, termed here the cross-organelle stress response (CORE). The proposed CORE pathway encompasses activation of protein conformational maintenance machineries, antioxidant enzymes and metabolic changes simultaneously in the cytosol, mitochondria and the ER. CORE induction extends replicative and chronological lifespan in budding yeast, highlighting its protective role against moderate proteotoxicity and its consequences such as the decline in respiration. Our findings accentuate that organelles do not function in isolation, but are integrated in a functional crosstalk, while also highlighting the importance of organelle communication in aging and age-related diseases.
A broadband terahertz ultrathin multi-focus lens
Authors: He Jingwen , Ye Jiasheng , Wang Xinke , Kan Qiang , Zhang Yan
Published: June 2016

Ultrathin transmission metasurface devices are designed on the basis of the Yang-Gu amplitude-phase retrieval algorithm for focusing the terahertz (THz) radiation into four or nine spots with focal spacing of 2 or 3 mm at a frequency of 0.8 THz. The focal properties are experimentally investigated in detail, and the results agree well with the theoretical expectations. The designed THz multi-focus lens (TMFL) demonstrates a good focusing function over a broad frequency range from 0.3 to 1.1 THz. As a transmission-type device based on metasurface, the diffraction efficiency of the TMFL can be as high as 33.92% at the designed frequency. The imaging function of the TMFL is also demonstrated experimentally and clear images are obtained. The proposed method produces an ultrathin, low-cost, and broadband multi-focus lens for THz-band application
The Cannabinoid Receptor 2 Protects Against Alcoholic Liver Disease Via a Macrophage Autophagy-Dependent Pathway
Authors: Denaës Timothé , Lodder Jasper , Chobert Marie-Noële , Ruiz Isaac , Pawlotsky Jean-Michel , Lotersztajn Sophie , Teixeira-Clerc Fatima
Published: June 2016

Kupffer cells, the resident macrophages of the liver, play a major role in the pathogenesis of alcoholic liver disease. We have previously demonstrated that CB2 receptor protects against alcoholic liver disease by inhibiting alcohol-induced inflammation and steatosis via the regulation of Kupffer cell activation. Here, we explored the mechanism underlying these effects and hypothesized that the anti-inflammatory properties of CB2 receptor in Kupffer cells rely on activation of autophagy. For this purpose, mice invalidated for CB2 receptor (CB2Mye−/− mice) or for the autophagy gene ATG5 (ATG5Mye−/− mice) in the myeloid lineage and their littermate wild-type mice were subjected to chronic-plus-binge ethanol feeding. CB2Mye−/− mice showed exacerbated alcohol-induced pro-inflammatory gene expression and steatosis. Studies in cultured macrophages demonstrated that CB2 receptor activation by JWH-133 stimulated autophagy via a heme oxygenase-1 dependent pathway. Moreover, JWH-133 reduced the induction of inflammatory genes by lipopolysaccharide in wild-type macrophages, but not in ATG5-deficient cells. The CB2 agonist also protected from alcohol-induced liver inflammation and steatosis in wild-type mice, but not in ATG5Mye−/− mice demonstrating that macrophage autophagy mediates the anti-inflammatory and anti-steatogenic effects of CB2 receptor. Altogether these results demonstrate that CB2 receptor activation in macrophages protects from alcohol-induced steatosis by inhibiting hepatic inflammation through an autophagy-dependent pathway.
Harnessing solid-state packing for selective detection of chloride in a macrocyclic anionophore
Authors: Vonnegut Chris L. , Shonkwiler Airlia M. , Zakharov Lev N. , Haley Michael M. , Johnson Darren W.
Published: June 2016

We report the synthesis of a macrocyclic receptor that displays a selective fluorescent response to chloride in the solid state.
Decarboxylative Csp3–Csp3 coupling for benzylation of unstable ketone enolates: synthesis of p-(acylethyl)phenols
Authors: Wang Sasa , Chen Xinzheng , Ao Qiaoqiao , Wang Huifei , Zhai Hongbin
Published: June 2016

A new decarboxylative Csp3–Csp3 coupling approach for the benzylation of ketone enolates has been developed.
Self-assembly of PEGylated gold nanoparticles with satellite structures as seeds
Authors: Bachelet Marie , Chen Rongjun
Published: June 2016

Satellite structures are reported to act as seeds for the self-assembly of PEGylated gold nanoparticles through a slow evaporation process.
Targeted fluorescence imaging enhanced by 2D materials: a comparison between 2D MoS2 and graphene oxide
Authors: Xie Donghao , Ji Ding-Kun , Zhang Yue , Cao Jun , Zheng Hu , Liu Lin , Zang Yi , Li Jia , Chen Guo-Rong , James Tony D. , He Xiao-Peng
Published: June 2016

2D MoS2 enhances the receptor-targeting cell and tissue imaging ability of a fluorophore-labeled ligand in a concentration-dependent manner.
How many enzyme molecules are needed for discrimination oriented applications?
Authors: Gorecki Jerzy , Gorecka Joanna N. , Nowakowski Bogdan , Ueno Hiroshi , Yoshikawa Kenichi
Published: June 2016

The considered discriminator of parameters describing periodic inflow of reagent X operating with an enzymatic reaction.
Polyferrocenylsilanes: synthesis, properties, and applications
Authors: Hailes Rebekah L. N. , Oliver Alex M. , Gwyther Jessica , Whittell George R. , Manners Ian
Published: June 2016

This comprehensive review covers polyferrocenylsilanes (PFSs), a well-established, readily accessible class of main chain organosilicon metallopolymer. The focus is on the recent advances involving PFS homopolymers and block copolymers and the article covers the synthesis, properties, and applications of these fascinating materials.
Gas phase oxidation of 2-methyl-1,3-propanediol to methacrylic acid over heteropolyacid catalysts
Authors: Darabi Mahboub Mohammad Jaber , Lotfi Samira , Dubois Jean-Luc , Patience Gregory S.
Published: June 2016

Heteropolyacids with Cs, V and Cu partially oxidize 2MPDO to methacrylic acid (40% selectivity) in the gas phase at 250 °C.
Transition metal-free oxidative ortho-acylation of phenols with N-heteroarylmethanes via double C–H activation
Authors: Liu Min , Chen Tieqiao , Zhou Yongbo , Yin Shuang-Feng
Published: June 2016

The direct oxidative acylation of phenols with N-heteroarylmethanes via sp3C–H and sp2C–H double activation was achieved under metal-free conditions. The reaction proceeds in a facile I2/DMSO/O2 system regio-selectively to produce valuable (2-hydroxyphenyl)arylmethanones. A plausible mechanism was proposed.
Oxygen activation and catalytic aerobic oxidation by Mo(iv)/(vi) complexes with functionalized iminophenolate ligands
Authors: Zwettler Niklas , Judmaier Martina E. , Strohmeier Lara , Belaj Ferdinand , Mösch-Zanetti Nadia C.
Published: June 2016

Dioxidomolybdenum(vi) complexes coordinated by functionalized bidentate iminophenolate ligands undergo oxygen atom transfer to PMe3 to yield molybdenum(iv) oxido phosphino species that readily react with molecular O2 to form molybdenum(vi) oxido peroxido complexes.
Electron transfer mechanism of catalytic superoxide dismutation via Cu(ii/i) complexes: evidence of cupric–superoxo/–hydroperoxo species
Authors: Maji Ram Chandra , Das Partha Pratim , Mishra Saikat , Bhandari Anirban , Maji Milan , Patra Apurba K.
Published: June 2016

{Cupric–superoxo ⇌ cupric–peroxo} → cupric–hydroperoxo conversion and the electron transfer mechanism of catalytic superoxide dismutation have been probed with a set of Cu(ii/i) complexes.
Environmental transmission of diarrheal pathogens in low and middle income countries
Authors: Julian Timothy R.
Published: June 2016

Globally more than half a million children die every year from diarrheal diseases. ThisPerspectivesuggests that reductions in diarrheal disease transmission in LMICs can be achieved by accounting for site-specific factors when designing environmental interventions. This is discussed in the context of the characteristics of the most important diarrheal diseases as well as environmental reservoirs.
A variational approach to nucleation simulation
Authors: Piaggi Pablo M. , Valsson Omar , Parrinello Michele
Published: June 2016

We study by computer simulation the nucleation of a supersaturated Lennard-Jones vapor into the liquid phase. The large free energy barriers to transition make the time scale of this process impossible to study by ordinary molecular dynamics simulations. Therefore we use a recently developed enhanced sampling method [Valsson and Parrinello, Phys. Rev. Lett.113, 090601 (2014)] based on the variational determination of a bias potential. We differ from previous applications of this method in that the bias is constructed on the basis of the physical model provided by the classical theory of nucleation. We examine the technical problems associated with this approach. Our results are very satisfactory and will pave the way for calculating the nucleation rates in many systems.
On the way to greener ionic liquids: identification of a fully mineralizable phenylalanine-based ionic liquid
Authors: Haiß Annette , Jordan Andrew , Westphal Janin , Logunova Evgenia , Gathergood Nicholas , Kümmerer Klaus
Published: June 2016

Biodegradability screening ofl-phenylalanine based ILs and LC-HRMS analysis of the degradation products led to the identification of a pyridinium IL which was fully mineralizable and is proposed as a basic structure for green ILs.
Electroactive biomimetic collagen-silver nanowire composite scaffolds
Authors: Wickham Abeni , Vagin Mikhail , Khalaf Hazem , Bertazzo Sergio , Hodder Peter , Dånmark Staffan , Bengtsson Torbjörn , Altimiras Jordi , Aili Daniel
Published: June 2016

A tissue-mimetic collagen-silver nanowire composite material has been developed that offers charge storage and injection capacities similar to conjugated polymer scaffolds while supporting proliferation of cardiomyocytes and providing antimicrobial activity.
Formation of long sub-chain hyperbranched poly(methyl methacrylate) based on inhibited self-cyclization of seesaw macromonomers
Authors: Li Peng-Yun , He Wei-Dong , Chen Sheng-Qi , Lu Xiao-Xia , Li Jia-Min , Li Hui-Juan
Published: June 2016

Well-defined hyperbranched PMMA almost without self-cyclization was obtained through a click reaction, facilitated by a high concentration, good solvent and disubstituted chain ends.
Preparation of CO2-switchable graphene dispersions and their polystyrene nanocomposite latexes by direct exfoliation of graphite using hyperbranched polyethylene surfactants
Authors: Yan Su , Zhang Qi , Wang Wen-Jun , Li Bo-Geng
Published: June 2016

Herein the preparation of CO2-switchable graphene dispersions by noncovalent exfoliation of graphite in water using a CO2-switchable star copolymer surfactant is described.
Novel solution-processable functional polyimide/ZrO2 hybrids with tunable digital memory behaviors
Authors: Tsai Chia-Liang , Lee Tzong-Ming , Liou Guey-Sheng
Published: June 2016

The resulting PI hybrid films exhibited electrically programmable digital memory properties from DRAM, SRAM to WORM with a high ON/OFF current ratio by controlling the content of ZrO2 from 0 to 30 wt%.
An integrated electrochromic supercapacitor based on nanostructured Er-containing titania using an Er(iii)-doped polyoxotitanate cage
Authors: Lv Yaokang , Du Weishi , Ren Yan , Cai Zhiwei , Yu Kuai , Zhang Cheng , Chen Zuofeng , Wright Dominic S.
Published: June 2016

An integrated bifunctional EC supercapacitor was designed based on nanostructured Er-containing titania due to its EC properties and Li+ ion storage capacity. This new material is derived from a novel Er(iii)-doped polyoxotitanate cage [Ti8O7(OEt)21Er].
Optimization of nano-sized Ni/MgAl2O4 catalyst synthesis by the surfactant-assisted deposition precipitation method for steam pre-reforming of natural gas
Authors: Keshavarz Ahmad Reza , Soleimani Mansooreh
Published: June 2016

In this work, steam pre-reforming of natural gas over magnesium aluminate-supported nickel catalysts (Ni/MgAl2O4) was studied.
Fundamentals of chemical incorporation of ionic monomers onto polymer colloids: paving the way for surfactant-free waterborne dispersions
Authors: Bilgin Sevilay , Tomovska Radmila , Asua José M.
Published: June 2016

Surfactant-free stable emulsion polymerization by controlling the chemical incorporation of ionic monomers through the water solubility of the comonomer.
1D oriented attachment of calcite nanocrystals: formation of single-crystalline rods through collision
Authors: Takasaki Mihiro , Kimura Yuki , Yamazaki Tomoya , Oaki Yuya , Imai Hiroaki
Published: June 2016

Single-crystalline calcite nanorods elongated in the c direction formed through 1D oriented attachment of nanoblocks.
Enzyme mediated biomass pretreatment and hydrolysis: a biotechnological venture towards bioethanol production
Authors: Chandra Rajak Rajiv , Banerjee Rintu
Published: June 2016

Biobased processes are gaining major interest worldwide with considerable efforts now being applied to developing efficient technologies for bioresource utilization.
Evaluation of l-tyrosine mixed with sodium dodecyl sulphate or cetyl pyridinium chloride as a corrosion inhibitor for mild steel in 1 M HCl: experimental and theoretical studies
Authors: Parveen Mosarrat , Mobin Mohammad , Zehra Saman
Published: June 2016

The inhibition effect of l-tyrosine mixed with sodium dodecyl sulphate or cetyl pyridinium chloride on mild steel corrosion in HCl was studied.
Mini-review: fluorescence imaging in cancer cells using dye-doped nanoparticles
Authors: Jenkins Ragini , Burdette Mary K. , Foulger Stephen H.
Published: June 2016

Fluorescence imaging has gained increased attention over the past two decades as a viable means to detect a variety of cancers.
Induction of intrinsic apoptotic pathway and cell cycle arrest via baicalein loaded iron oxide nanoparticles as a competent nano-mediated system for triple negative breast cancer therapy
Authors: Kavithaa Krishnamoorthy , Paulpandi Manickam , Padma Palghat Raghunathan , Sumathi Sundaravadivelu
Published: June 2016

Magnetic nanoparticles have shown an increasing number of applications in the field of molecular medicine.
Electrokinetic properties and stability of cerium dioxide suspensions
Authors: Barany S. , Bohacs K. , Chepurna I. , Meszaros R.
Published: June 2016

The aggregation regularities of large CeO2 particles as a function of aging, pH, ultrasonic treatment and concentration of added electrolytes have been studied using laser diffraction and microphoresis.
Substituent effect on the spin state of the graphene nanoflakes
Authors: Flores Reyes , Torres Ana E. , Fomine Serguei
Published: June 2016

Substituents affect the total spin of the graphene nanoflakes ground states.
A novel approach to fabricate stable graphene layers on electrode surfaces using simultaneous electroreduction of diazonium cations and graphene oxide
Authors: Kesavan Srinivasan , John S. Abraham
Published: June 2016

Short time preparation of stable graphene layers was fabricated on electrode surface using simultaneous electroreduction of diazonium salts and graphene oxide.
Click-chemistry approaches to π-conjugated polymers for organic electronics applications
Authors: Marrocchi Assunta , Facchetti Antonio , Lanari Daniela , Santoro Stefano , Vaccaro Luigi
Published: June 2016

A survey of papers exploring the scope of click chemistry in the area of π-conjugated polymers for organic electronics is given.
Atmospheric-pressure ionization and fragmentation of peptides by solution-cathode glow discharge
Authors: Schwartz Andrew J. , Shelley Jacob T. , Walton Courtney L. , Williams Kelsey L. , Hieftje Gary M.
Published: June 2016

Ionization and tunable fragmentation of peptides at atmospheric pressure was achieved by means of a solution-cathode glow discharge ionization source.
Molecular engineering of Ni–/Co–porphyrin multilayers on reduced graphene oxide sheets as bifunctional catalysts for oxygen evolution and oxygen reduction reactions
Authors: Sun Jiqing , Yin Huajie , Liu Porun , Wang Yun , Yao Xiangdong , Tang Zhiyong , Zhao Huijun
Published: June 2016

Ni– and Co–porphyrin multilayers on reduced graphene oxide (rGO) sheets are reported as novel bifunctional catalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR).
Asperterpenes A and B, two unprecedented meroterpenoids from Aspergillus terreus with BACE1 inhibitory activities
Authors: Qi Changxing , Bao Jian , Wang Jianping , Zhu Hucheng , Xue Yongbo , Wang Xiaochuan , Li Hua , Sun Weiguang , Gao Weixi , Lai Yongji , Chen Jian-Guo , Zhang Yonghui
Published: June 2016

Asperterpenes A and B, two BACE1 inhibitors with unprecedented carbon skeletons isolated fromAspergillus terreus, exhibit potent anti-Alzheimer's disease activity.
Impact of the alkyl side chain position on the photovoltaic properties of solution-processable organic molecule donor materials
Authors: Zhang J. , Zhu X. W. , He C. , Bin H. J. , Xue L. W. , Wang W. G. , Yang Y. K. , Yuan N. Y. , Ding J. N. , Wei Z. X. , Zhang Z.-G. , Li Y. F.
Published: June 2016

Two new compounds with alkyl side chains at different positions have a similar structure, but exhibit different photovoltaic properties.
Improving the functionality of carbon nanodots: doping and surface functionalization
Authors: Park Y. , Yoo J. , Lim B. , Kwon W. , Rhee S.-W.
Published: June 2016

This review covers recent progress in atomic doping and surface functionalization of carbon nanodots to improve their functionality for a variety of applications ranging from biomedicine to optoelectronics to energy.
Control approach of three‐phase grid connected PV inverters for voltage unbalance mitigation in low‐voltage distribution grids
Authors: El‐Naggar Ahmed , Erlich Istvàn
Published: June 2016

Low‐voltage distribution grids (LV) experience unbalanced voltage condition due to the high penetration levels of rooftop mounted single‐phase photovoltaic (PV), the existence of single‐phase transformers, unbalanced cable impedances and different load levels on each phase. The voltage unbalance (VU) has a harmful impact on the loads and equipment connected to grid that leads to overheating and fast thermal ageing. There are several solutions proposed to mitigate the VU, that requires the installation of extra hardware components or incorporate complex type of controllers that need special tuning procedures and special arrangements. Therefore, in this study a new and simple control approach of three‐phase grid connected PV inverter is proposed to mitigate the unbalanced voltage. The new control approach is able to fully mitigate the unbalanced voltage without the need to extra hardware installation or negative sequence voltage magnitude and phase angle measurements, provided that the ampacity of the converter is high enough. The new system is tested in a LV grid with high PV penetration from Germany. The results show that the VU factor did not exceed 0.8% at the feeder connection point.
Penetrating Craniomaxillofacial Injury Caused by a Pneumatic Nail Gun
Authors: Choi Kevin Jae , Ryan Marisa Ann , Cheng Tracy , Powers David
Published: June 2016

Craniomaxillofacial injuries can be complex, requiring a multidisciplinary approach. The primary survey is always the first step in trauma management prior to proceeding with further evaluation and treatment. A 26-year-old man presented with a penetrating nail gun injury through the oral and nasal cavities. He did not present in extremis but required elective endotracheal intubation for intraoperative assessment and treatment. Airway management was enhanced by the use of lingual nerve and inferior alveolar nerve blocks via the Vazirani-Akinosi technique to maintain spontaneous respiration while the tongue was distracted from the palate. The nail was removed and rapid sequence induction initiated for orotracheal intubation. Local nerve blocks can be an effective tool in the armamentarium of the craniomaxillofacial trauma surgeon in managing blunt and penetrating injuries. We demonstrate its utility in airway management when a penetrating foreign body in the upper airway precludes orotracheal or nasotracheal intubation.
Effects of radiation reaction in the interaction between cluster media and high intensity lasers in the radiation dominant regime
Authors: Iwata Natsumi , Nagatomo Hideo , Fukuda Yuji , Matsui Ryutaro , Kishimoto Yasuaki
Published: June 2016

Interaction between media composed of clusters and high intensity lasers in the radiation dominant regime, i.e., intensity of 1022−23 W/cm2, is studied based on the particle-in-cell simulation that includes the radiation reaction. By introducing target materials that have the same total mass but different internal structures, i.e., uniform plasma and cluster media with different cluster radii, we investigate the effect of the internal structure on the interaction dynamics, high energy radiation emission, and its reaction. Intense radiation emission is found in the cluster media where electrons exhibit non-ballistic motions suffering from strong accelerations by both the penetrated laser field and charge separation field of clusters. As a result, the clustered structure increases the energy conversion into high energy radiations significantly at the expense of the conversion into particles, while the total absorption rate into radiation and particles remains unchanged from the absorption rate into particles in the case without radiation reaction. The maximum ion energy achieved in the interaction with cluster media is found to be decreased through the radiation reaction to electrons into the same level with that achieved in the interaction with the uniform plasma. The clustered structure thus enhances high energy radiation emission rather than the ion acceleration in the considered intensity regime.
Algebraic solutions of shape-invariant position-dependent effective mass systems
Authors: Amir Naila , Iqbal Shahid
Published: June 2016

Keeping in view the ordering ambiguity that arises due to the presence of position-dependent effective mass in the kinetic energy term of the Hamiltonian, a general scheme for obtaining algebraic solutions of quantum mechanical systems with position-dependent effective mass is discussed. We quantize the Hamiltonian of the pertaining system by using symmetric ordering of the operators concerning momentum and the spatially varying mass, initially proposed by von Roos and Lévy-Leblond. The algebraic method, used to obtain the solutions, is based on the concepts of supersymmetric quantum mechanics and shape invariance. In order to exemplify the general formalism a class of non-linear oscillators has been considered. This class includes the particular example of a one-dimensional oscillator with different position-dependent effective mass profiles. Explicit expressions for the eigenenergies and eigenfunctions in terms of generalized Hermite polynomials are presented. Moreover, properties of these modified Hermite polynomials, like existence of generating function and recurrence relations among the polynomials have also been studied. Furthermore, it has been shown that in the harmonic limit, all the results for the linear harmonic oscillator are recovered.
Improved mid infrared detector for high spectral or spatial resolution and synchrotron radiation use
Authors: Faye Mbaye , Bordessoule Michel , Kanouté Brahim , Brubach Jean-Blaise , Roy Pascale , Manceron Laurent
Published: June 2016

When using bright, small effective size sources, such as synchrotron radiation light beam, for broadband spectroscopy at spectral or spatial high resolution for mid-IR FTIR measurements, a marked detectivity improvement can be achieved by setting up a device matching the detector optical étendue to that of the source. Further improvement can be achieved by reducing the background unmodulated flux and other intrinsic noise sources using a lower temperature cryogen, such as liquid helium. By the combined use of cooled apertures, cold reimaging optics, filters and adapted detector polarization, and preamplification electronics, the sensitivity of a HgCdTe photoconductive IR detector can be improved by a significant factor with respect to standard commercial devices (more than one order of magnitude on average over 6–20 μm region) and the usable spectral range extended to longer wavelengths. The performances of such an optimized detector developed on the AILES Beamline at SOLEIL are presented here.
Lattice thermal conduction in ultra-thin nanocomposites
Authors: Thomas Iorwerth O. , Srivastava G. P.
Published: June 2016

We have studied the lattice thermal conductivity of Si/Ge periodic nanocomposites (superlattice, nanowire, and nanodot structures) of sample sizes in the range of 30 nm–30 μm, periodicities 1.1 nm and 2.2 nm, with reasonably dirty interfaces, and n-type doping concentration in the range of 1023–1026 m−3. Our calculations employ a judicious combination of ab initio and physically sound semi-empirical methods for detailed calculations of estimates of phonon scattering rates due to anharmonicity and interface formation. Based upon our results we conclude that the formation of ultra-thin nanocomposites in any of the three structures is capable of reducing the conductivity below the alloy limit. This can be explained as a result of combination of the sample length dependence, the on-set of mini-Umklapp three-phonon processes, mass mixing at the interfaces between Si and Ge regions, and the sample doping level.
A “twisted” microfluidic mixer suitable for a wide range of flow rate applications
Authors: Sivashankar Shilpa , Agambayev Sumeyra , Mashraei Yousof , Li Er Qiang , Thoroddsen Sigurdur T. , Salama Khaled Nabil
Published: June 2016

This paper proposes a new “twisted” 3D microfluidic mixer fabricated by a laser writing/microfabrication technique. Effective and efficient mixing using the twisted micromixers can be obtained by combining two general chaotic mixing mechanisms: splitting/recombining and chaotic advection. The lamination of mixer units provides the splitting and recombination mechanism when the quadrant of circles is arranged in a two-layered serial arrangement of mixing units. The overall 3D path of the microchannel introduces the advection. An experimental investigation using chemical solutions revealed that these novel 3D passive microfluidic mixers were stable and could be operated at a wide range of flow rates. This micromixer finds application in the manipulation of tiny volumes of liquids that are crucial in diagnostics. The mixing performance was evaluated by dye visualization, and using a pH test that determined the chemical reaction of the solutions. A comparison of the tornado-mixer with this twisted micromixer was made to evaluate the efficiency of mixing. The efficiency of mixing was calculated within the channel by acquiring intensities using ImageJ software. Results suggested that efficient mixing can be obtained when more than 3 units were consecutively placed. The geometry of the device, which has a length of 30 mm, enables the device to be integrated with micro total analysis systems and other lab-on-chip devices.
Suppression of the ferromagnetic order in the Heusler alloy Ni50Mn35In15 by hydrostatic pressure
Authors: Salazar Mejía C. , Mydeen K. , Naumov P. , Medvedev S. A. , Wang C. , Hanfland M. , Nayak A. K. , Schwarz U. , Felser C. , Nicklas M.
Published: June 2016

We report on the effect of hydrostatic pressure on the magnetic and structural properties of the shape-memory Heusler alloy Ni50Mn35In15. Magnetization and x-ray diffraction experiments were performed at hydrostatic pressures up to 5 GPa using diamond anvil cells. Pressure stabilizes the martensitic phase, shifting the martensitic transition to higher temperatures, and suppresses the ferromagnetic austenitic phase. Above 3 GPa, where the martensitic-transition temperature approaches the Curie temperature in the austenite, the magnetization shows no longer indications of ferromagnetic ordering. We further find an extended temperature region with a mixture of martensite and austenite phases, which directly relates to the magnetic properties.
Polarization-dependent plasmonic photocurrents in two-dimensional electron systems
Authors: Popov V. V.
Published: June 2016

Plasmonic polarization dependent photocurrents in a homogeneous two-dimensional electron system are studied. Those effects are completely different from the photon drag and electronic photogalvanic effects as well as from the plasmonic ratchet effect in a density modulated two-dimensional electron system. Linear and helicity-dependent contributions to the photocurrent are found. The linear contribution can be interpreted as caused by the longitudinal and transverse plasmon drag effect. The helicity-dependent contribution originates from the non-linear electron convection and changes its sign with reversing the plasmonic field helicity. It is shown that the helicity-dependent component of the photocurrent can exceed the linear one by several orders of magnitude in high-mobility two-dimensional electron systems. The results open possibilities for all-electronic detection of the radiation polarization states by exciting the plasmonic photocurrents in two-dimensional electron systems.
Multi-MHz time-of-flight electronic bandstructure imaging of graphene on Ir(111)
Authors: Tusche C. , Goslawski P. , Kutnyakhov D. , Ellguth M. , Medjanik K. , Elmers H. J. , Chernov S. , Wallauer R. , Engel D. , Jankowiak A. , Schönhense G.
Published: June 2016

In the quest for detailed spectroscopic insight into the electronic structure at solid surfaces in a large momentum range, we have developed an advanced experimental approach. It combines the 3D detection scheme of a time-of-flight momentum microscope with an optimized filling pattern of the BESSY II storage ring. Here, comprehensive data sets covering the full surface Brillouin zone have been used to study faint substrate-film hybridization effects in the electronic structure of graphene on Ir(111), revealed by a pronounced linear dichroism in angular distribution. The method paves the way to 3D electronic bandmapping with unprecedented data recording efficiency.
Phonon heat transport in superlattices: Case of Si/SiGe and SiGe/SiGe superlattices
Authors: Hijazi M. , Kazan M.
Published: June 2016

We present a predictive Boltzmann model for the cross-plane thermal conductivity in superlattices. The developed model considers particle-like phonons exhibiting wave characteristics at the interfaces and makes the assumption that the phonon heat transport in a superlattice has a mixed character. Exact Boltzmann equation comprising spatial dependence of phonon distribution function is solved to yield a general expression for the lattice thermal conductivity. The intrinsic phonon scattering rates are calculated from Fermi’s golden rule, and the model vibrational parameters are derived as functions of temperature and crystallographic directions by using elasticity theory-based lattice dynamics approach. The developed theory is then adapted to calculate the cross-plane thermal conductivity of superlattices. It is assumed that the phonons of wavelengths comparable or smaller than the superlattice period or the root mean square irregularity at the superlattice interfaces may be subject to a resistive scattering mechanism at the interfaces, whereas the phonons of wavelengths much greater than the superlattice period undergo ballistic transmission through the interfaces and obey dispersion relations determined by the Brillouin zone folding effects of the superlattice. The accuracy of the concept of mixed phonon transport regime in superlattices is demonstrated clearly with reference to experimental measurements regarding the effects of period thickness and temperature on the cross-plane thermal conductivity of Si/Si0.7Ge0.3 and Si0.84Ge0.16/Si0.76Ge0.3 superlattices.
Multiporous carbon allotropes transformed from symmetry-matched carbon nanotubes
Authors: Cai Yingxiang , Wang Hao , Xu Shengliang , Hu Yujie , Liu Ning , Xu Xuechun
Published: June 2016

Carbon nanotubes (CNTs) with homogeneous diameters have been proven to transform into new carbon allotropes under pressure but no studies on the compression of inhomogeneous CNTs have been reported. In this study, we propose to build new carbon allotropes from the bottom-up by applying pressure on symmetry-matched inhomogeneous CNTs. We find that the (3,0) CNT with point group C3v and the (6,0) CNT with point group C6v form an all sp3 hybridized hexagonal 3060-Carbon crystal, but the (4,0) CNT with point group D4h and the (8,0) CNT with point group D8h polymerize into a sp2+sp3 hybridized tetragonal 4080-Carbon structure. Their thermodynamic, mechanical and dynamic stabilities show that they are potential carbon allotropes to be experimentally synthesized. The multiporous structures, excellently mechanical properties and special electronic structures (semiconductive 3060-Carbon and semimetallic 4080-Carbon) imply their many potential applications, such as gases purification, hydrogen storage and lightweight semiconductor devices. In addition, we simulate their feature XRD patterns which are helpful for identifying the two carbon crystals in future experimental studies.
Band alignment of type I at (100)ZnTe/PbSe interface
Authors: Konovalov Igor , Emelianov Vitali , Linke Ralf
Published: June 2016

A junction of lattice-matched cubic semiconductors ZnTe and PbSe results in a band alignment of type I so that the narrow band gap of PbSe is completely within the wider band gap of ZnTe. The valence band offset of 0.27 eV was found, representing a minor barrier during injection of holes from PbSe into ZnTe. Simple linear extrapolation of the valence band edge results in a smaller calculated band offset, but a more elaborate square root approximation was used instead, which accounts for parabolic bands. PbSe was electrodeposited at room temperature with and without Cd2+ ions in the electrolyte. Although Cd adsorbs at the surface, the presence of Cd in the electrolyte does not influence the band offset.
GRIM-19, a gene associated with retinoid-interferon-induced mortality, affects endometrial receptivity and embryo implantation
Authors: Yang Yang , Sun Yanyan , Cheng Laiyang , Li Anna , Shen Yanjun , Jiang Ligang , Deng Xiaohui , Chao Lan
Published: June 2016

GRIM-19 is associated with apoptosis, abnormal proliferation, immune tolerance and malignant transformation, and it also plays an important role in early embryonic development. Although the homologous deletion of GRIM-19 causes embryonic lethality in mice, the precise role of GRIM-19 in embryo implantation has not been elucidated. Here we show that GRIM-19 plays an important role in endometrial receptivity and embryo implantation. Day 1 to Day 6 pregnant mouse uteri were collected. Immunohistochemistry studies revealed the presence of GRIM-19 on the luminal epithelium and glandular epithelium throughout the implantation period in pregnant mice. The protein and mRNA levels of GRIM-19 were markedly decreased on Day 4 of pregnancy in pregnant mice, but there was no change in GRIM-19 levels in a group of pseudopregnant mice. Overexpression of GRIM-19 decreased the adhesion rate of RL95–2–BeWo co-cultured spheroids and increased apoptosis. Furthermore, STAT3 and IL-11 mRNA and protein levels were reduced by overexpressing GRIM-19, but protein and mRNA levels of TNF-α were increased. These findings indicate the involvement of GRIM-19 in the embryo implantation process by regulating adhesion, apoptosis and immune tolerance.
Nitrification rates and associated nitrous oxide emissions from agricultural soils – a synopsis
Authors: Farquharson Ryan
Published: June 2016

Laboratory incubations were performed to estimate nitrification rates and the associated nitrous oxide (N2O) emissions under aerobic conditions on a range of soils from National Agricultural Nitrous Oxide Research Program field sites. Significant site-to-site variability in nitrification rates and associated N2O emissions was observed under standardised conditions, indicating the need for site-specific model parameterisation. Generally, nitrification rates and N2O emissions increased with higher water content, ammonium concentration and temperature, although there were exceptions. It is recommended that site-specific model parameterisation be informed by such data. Importantly, the ratio of N2O emitted to net nitrified N under aerobic conditions was small (<0.2% for the majority of measurements) but did vary from 0.03% to 1%. Some models now include variation in the proportion of nitrified N emitted as N2O as a function of water content; however, strong support for this was not found across all of our experiments, and the results demonstrate a potential role of pH and ammonium availability. Further research into fluctuating oxygen availability and the coupling of biotic and abiotic processes will be required to progress the process understanding of N2O emissions from nitrification.