bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrative omics connects N-glycoproteome-wide alterations with pathways and regulatory events in induced pluripotent stem cells
Authors: Sudhir Putty-Reddy , Kumari Madireddy Pavana , Hsu Wei-Ting , Chen Chein-Hung , Kuo Hung-Chih , Chen Chung-Hsuan
Published: November 2016

Molecular-level differences ranging from genomes to proteomes, but not N-glycoproteomes, between human induced pluripotent stem cells (hiPSCs) and embryonic stem cells (hESCs) have been assessed to gain insights into cell reprogramming and induced pluripotency. Our multiplexed quantitative N-glycoproteomics study identified altered N-glycoproteins that significantly regulate cell adhesion processes in hiPSCs compared to hESCs. The integrative proteomics and functional network analyses of the altered N-glycoproteins revealed their significant interactions with known PluriNet (pluripotency-associated network) proteins. We found that these interactions potentially regulate various signaling pathways including focal adhesion, PI3K-Akt signaling, regulation of actin cytoskeleton, and spliceosome. Furthermore, the integrative transcriptomics analysis revealed that imperfectly reprogrammed subunits of the oligosaccharyltransferase (OST) and dolichol-phosphate-mannose synthase (DPM) complexes were potential candidate regulatory events for the altered N-glycoprotein levels. Together, the results of our study suggest that imperfect reprogramming of the protein complexes linked with the N-glycosylation process may result in N-glycoprotein alterations that affect induced pluripotency through their functional protein interactions.
The influence of warm ischemia elimination on kidney injury during transplantation – clinical and molecular study
Authors: Kamińska Dorota , Kościelska-Kasprzak Katarzyna , Chudoba Paweł , Hałoń Agnieszka , Mazanowska Oktawia , Gomółkiewicz Agnieszka , Dzięgiel Piotr , Drulis-Fajdasz Dominika , Myszka Marta , Lepiesza Agnieszka , Polak Wojciech , Boratyńska Maria , Klinger Marian
Published: November 2016

Kidney surface cooling was used during implantation to assess the effect of warm ischemia elimination on allograft function, histological changes and immune-related gene expression. 23 recipients were randomly assigned to a group operated on with kidney surface cooling during implantation (ice bag technique, IBT group), and the other 23 recipients receiving the contralateral kidney from the same donor were operated on with a standard technique. Three consecutive kidney core biopsies were obtained during the transplantation procedure: after organ recovery, after cold ischemia and after reperfusion. Gene expression levels were determined using low-density arrays (Format 32, TaqMan). The IBT group showed a significantly lower rate of detrimental events (delayed graft function and/or acute rejection, p = 0.015) as well as higher glomerular filtration rate on day 14 (p = 0.026). A greater decrease of MMP9 and LCN2 gene expression was seen in the IBT group during total ischemia (p = 0.003 and p = 0.018). Elimination of second warm ischemia reduced the number of detrimental events after kidney transplantation, and thus had influence on the short-term but not long-term allograft function. Surface cooling of the kidney during vascular anastomosis may reduce some detrimental effects of immune activation resulting from both brain death and ischemia-reperfusion injury.
Inhibition of hydrogen sulfide biosynthesis sensitizes lung adenocarcinoma to chemotherapeutic drugs by inhibiting mitochondrial DNA repair and suppressing cellular bioenergetics
Authors: Szczesny Bartosz , Marcatti Michela , Zatarain John R. , Druzhyna Nadiya , Wiktorowicz John E. , Nagy Péter , Hellmich Mark R. , Szabo Csaba
Published: November 2016

Therapeutic manipulation of the gasotransmitter hydrogen sulfide (H2S) has recently been proposed as a novel targeted anticancer approach. Here we show that human lung adenocarcinoma tissue expresses high levels of hydrogen sulfide (H2S) producing enzymes, namely, cystathionine beta-synthase (CBS), cystathionine gamma lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST), in comparison to adjacent lung tissue. In cultured lung adenocarcinoma but not in normal lung epithelial cells elevated H2S stimulates mitochondrial DNA repair through sulfhydration of EXOG, which, in turn, promotes mitochondrial DNA repair complex assembly, thereby enhancing mitochondrial DNA repair capacity. In addition, inhibition of H2S-producing enzymes suppresses critical bioenergetics parameters in lung adenocarcinoma cells. Together, inhibition of H2S-producing enzymes sensitize lung adenocarcinoma cells to chemotherapeutic agents via induction of mitochondrial dysfunction as shown in in vitro and in vivo models, suggesting a novel mechanism to overcome tumor chemoresistance.
Changeover from signalling to energy-provisioning lipids during transition from colostrum to mature milk in the giant panda (Ailuropoda melanoleuca)
Authors: Zhang Tong , Watson David G. , Zhang Rong , Hou Rong , Loeffler I. Kati , Kennedy Malcolm W.
Published: November 2016

Among the large placental mammals, ursids give birth to the most altricial neonates with the lowest neonatal:maternal body mass ratios. This is particularly exemplified by giant pandas. To examine whether there is compensation for the provision of developmentally important nutrients that other species groups may provide in utero, we examined changes in the lipids of colostrum and milk with time after birth in giant pandas. Lipids that are developmental signals or signal precursors, and those that are fundamental to nervous system construction, such as docosahexaenoic acid (DHA) and phosphatidylserines, appear early and then fall dramatically in concentration to a baseline at 20–30 days. The dynamics of lysophosphatidic acid and eicosanoids display similar patterns, but with progressive differences between mothers. Triglycerides occur at relatively low levels initially and increase in concentration until a plateau is reached at about 30 days. These patterns indicate an early provision of signalling lipids and their precursors, particularly lipids crucial to brain, retinal and central nervous system development, followed by a changeover to lipids for energy metabolism. Thus, in giant pandas, and possibly in all bears, lactation is adapted to provisioning a highly altricial neonate to a degree that suggests equivalence to an extension of gestation.
Using genome-wide CRISPR library screening with library resistant DCK to find new sources of Ara-C drug resistance in AML
Authors: Kurata Morito , Rathe Susan K. , Bailey Natashay J. , Aumann Natalie K. , Jones Justine M. , Veldhuijzen G. Willemijn , Moriarity Branden S. , Largaespada David A.
Published: November 2016

Acute myeloid leukemia (AML) can display de novo or acquired resistance to cytosine arabinoside (Ara-C), a primary component of induction chemotherapy. To identify genes capable of independently imposing Ara-C resistance, we applied a genome-wide CRISPR library to human U937 cells and exposed to them to Ara-C. Interestingly, all drug resistant clones contained guide RNAs for DCK. To avoid DCK gene modification, gRNA resistant DCK cDNA was created by the introduction of silent mutations. The CRISPR screening was repeated using the gRNA resistant DCK, and loss of SLC29A was identified as also being capable of conveying Ara-C drug resistance. To determine if loss of Dck results in increased sensitivity to other drugs, we conducted a screen of 446 FDA approved drugs using two Dck-defective BXH-2 derived murine AML cell lines and their Ara-C sensitive parental lines. Both cell lines showed an increase in sensitivity to prednisolone. Guide RNA resistant cDNA rescue was a legitimate strategy and multiple DCK or SLC29A deficient human cell clones were established with one clone becoming prednisolone sensitive. Dck-defective leukemic cells may become prednisolone sensitive indicating prednisolone may be an effective adjuvant therapy in some cases of DCK-negative AML.
Identification of a two-component Class IIb bacteriocin in Streptococcus pyogenes by recombinase-based in vivo expression technology
Authors: Armstrong Brent D. , Herfst Christine A. , Tonial Nicholas C. , Wakabayashi Adrienne T. , Zeppa Joseph J. , McCormick John K.
Published: November 2016

Streptococcus pyogenes is a globally prominent bacterial pathogen that exhibits strict tropism for the human host, yet bacterial factors responsible for the ability of S. pyogenes to compete within this limited biological niche are not well understood. Using an engineered recombinase-based in vivo expression technology (RIVET) system, we identified an in vivo-induced promoter region upstream of a predicted Class IIb bacteriocin system in the M18 serotype S. pyogenes strain MGAS8232. This promoter element was not active under in vitro laboratory conditions, but was highly induced within the mouse nasopharynx. Recombinant expression of the predicted mature S. pyogenes bacteriocin peptides (designated SpbM and SpbN) revealed that both peptides were required for antimicrobial activity. Using a gain of function experiment in Lactococcus lactis, we further demonstrated S. pyogenes immunity function is encoded downstream of spbN. These data highlight the importance of bacterial gene regulation within appropriate environments to help understand mechanisms of niche adaptation by bacterial pathogens.
Limited mitogenomic degradation in response to a parasitic lifestyle in Orobanchaceae
Authors: Fan Weishu , Zhu Andan , Kozaczek Melisa , Shah Neethu , Pabón-Mora Natalia , González Favio , Mower Jeffrey P.
Published: November 2016

In parasitic plants, the reduction in plastid genome (plastome) size and content is driven predominantly by the loss of photosynthetic genes. The first completed mitochondrial genomes (mitogenomes) from parasitic mistletoes also exhibit significant degradation, but the generality of this observation for other parasitic plants is unclear. We sequenced the complete mitogenome and plastome of the hemiparasite Castilleja paramensis (Orobanchaceae) and compared them with additional holoparasitic, hemiparasitic and nonparasitic species from Orobanchaceae. Comparative mitogenomic analysis revealed minimal gene loss among the seven Orobanchaceae species, indicating the retention of typical mitochondrial function among Orobanchaceae species. Phylogenetic analysis demonstrated that the mobile cox1 intron was acquired vertically from a nonparasitic ancestor, arguing against a role for Orobanchaceae parasites in the horizontal acquisition or distribution of this intron. The C. paramensis plastome has retained nearly all genes except for the recent pseudogenization of four subunits of the NAD(P)H dehydrogenase complex, indicating a very early stage of plastome degradation. These results lend support to the notion that loss of ndh gene function is the first step of plastome degradation in the transition to a parasitic lifestyle.
Effects of sedimentation on soil physical and chemical properties and vegetation characteristics in sand dunes at the Southern Dongting Lake region, China
Authors: Pan Ying , Zhang Hao , Li Xu , Xie Yonghong
Published: November 2016

Sedimentation is recognized as a major factor determining the ecosystem processes of lake beaches; however, the underlying mechanisms, especially in freshwater sand dunes, have been insufficiently studied. To this end, nine belt transects from nine freshwater sand dunes, classified into low (<23.7 m), medium (25.4–26.0 m), and high-elevation groups (>28.1 m) based on their elevations in 1972, were sampled to investigate differences in sedimentation rate and soil and vegetation characteristics in Southern Dongting Lake, China. Sedimentation rate, soil sand content, and soil pH increased, whereas soil clay, fine silt, moisture (MC), organic matter (OM), total N, and total K content, in addition to the growth and biodiversity of sand dune plants generally decreased with decreasing belt transect elevation. Regression analyses revealed that the negative effects of sedimentation on the ecosystem functions of sand dunes could be attributed to higher fine sand content in deposited sediments and stronger inhibition of plant growth. These results are consistent with previous studies performed in coastal sand dunes, which highlights the importance of sedimentation in determining ecological processes.
Constructing safe and durable antibacterial textile surfaces using a robust graft-to strategy via covalent bond formation
Authors: He Liang , Li Sha , Chung Cordelia T. W. , Gao Chang , Xin John H.
Published: November 2016

Recently zwitterionic materials have been widely applied in the biomedical and bioengineering fields due to their excellent biocompatibility. Inspired by these, this study presents a graft-to strategy via covalent bond formation to fabricate safe and durable antibacterial textile surfaces. A novel zwitterionic sulfobetaine containing triazine reactive group was specifically designed and synthesized. MTT assay showed that it had no obvious cytotoxicity to human skin HaCaT cells as verified by ca. 89.9% relative viability at a rather high concentration of 0.8 mg·mL−1. In the evaluation for its skin sensitization, the maximum score for symptoms of erythema and edema in all tests were 0 in all observation periods. The sulfobetaine had a hydrophilic nature and the hydrophilicity of the textiles was enhanced by 43.9% when it was covalently grafted onto the textiles. Moreover, the textiles grafted with the reactive sulfobetaine exhibited durable antibacterial activities, which was verified by the fact that they showed antibacterial rates of 97.4% against gram-positive S. aureus and 93.2% against gram-negative E. coli even after they were laundered for 30 times. Therefore, the titled zwitterionic sulfobetaine is safe to human for healthcare and wound dressing and shows a promising prospect on antibacterial textile application.
Sensitivity of El Niño intensity and timing to preceding subsurface heat magnitude
Authors: Ballester Joan , Petrova Desislava , Bordoni Simona , Ben Cash  , García-Díez Markel , Rodó Xavier
Published: November 2016

Despite extensive ongoing efforts on improving the long-term prediction of El Niño-Southern Oscillation, the predictability in state-of-the-art operational schemes remains limited by factors such as the spring barrier and the influence of atmospheric winds. Recent research suggests that the 2014/15 El Niño (EN) event was stalled as a result of an unusually strong basin-wide easterly wind burst in June, which led to the discharge of a large fraction of the subsurface ocean heat. Here we use observational records and numerical experiments to explore the sensitivity of EN to the magnitude of the heat buildup occurring in the ocean subsurface 21 months in advance. Our simulations suggest that a large increase in heat content during this phase can lead to basin-wide uniform warm conditions in the equatorial Pacific the winter before the occurrence of a very strong EN event. In our model configuration, the system compensates any initial decrease in heat content and naturally evolves towards a new recharge, resulting in a delay of up to one year in the occurrence of an EN event. Both scenarios substantiate the non-linear dependency between the intensity of the subsurface heat buildup and the magnitude and timing of subsequent EN episodes.
Structural basis of the high thermal stability of the histone-like HU protein from the mollicute Spiroplasma melliferum KC3
Authors: Boyko Konstantin M. , Rakitina Tatiana V. , Korzhenevskiy Dmitry A. , Vlaskina Anna V. , Agapova Yuliya K. , Kamashev Dmitry E. , Kleymenov Sergey Y. , Popov Vladimir O.
Published: November 2016

The three-dimensional structure of the histone-like HU protein from the mycoplasma Spiroplasma melliferum KC3 (HUSpm) was determined at 1.4 Å resolution, and the thermal stability of the protein was evaluated by differential scanning calorimetry. A detailed analysis revealed that the three-dimensional structure of the HUSpm dimer is similar to that of its bacterial homologues but is characterized by stronger hydrophobic interactions at the dimer interface. This HUSpm dimer interface lacks salt bridges but is stabilized by a larger number of hydrogen bonds. According to the DSC data, HUSpm has a high denaturation temperature, comparable to that of HU proteins from thermophilic bacteria. To elucidate the structural basis of HUSpm thermal stability, we identified amino acid residues potentially responsible for this property and modified them by site-directed mutagenesis. A comparative analysis of the melting curves of mutant and wild-type HUSpm revealed the motifs that play a key role in protein thermal stability: non-conserved phenylalanine residues in the hydrophobic core, an additional hydrophobic loop at the N-terminal region of the protein, the absence of the internal cavity present at the dimer interface of some HU proteins, and the presence of additional hydrogen bonds between the monomers that are missing in homologous proteins.
Epac1 interacts with importin β1 and controls neurite outgrowth independently of cAMP and Rap1
Authors: Baameur Faiza , Singhmar Pooja , Zhou Yong , Hancock John F. , Cheng Xiaodong , Heijnen Cobi J. , Kavelaars Annemieke
Published: November 2016

Exchange protein directly activated by cAMP-1 (Epac1) is a cAMP sensor that regulates multiple cellular functions including cellular migration, proliferation and differentiation. Classically, Epac1 is thought to exert its effects through binding of cAMP leading to a conformational change in Epac1 and its accumulation at the plasma membrane (PM) where it activates Rap1. In search for regulators of Epac1 activity, we show here that importin β1 (impβ1) is an Epac1 binding partner that prevents PM accumulation of Epac1. We demonstrate that in the absence of impβ1, endogenous as well as overexpressed Epac1 accumulate at the PM. Moreover, agonist-induced PM translocation of Epac1 leads to dissociation of Epac1 from impβ1. Localization of Epac1 at the PM in the absence of impβ1, requires residue R82 in its DEP domain. Notably, the PM accumulation of Epac1 in the absence of impβ1 does not require binding of cAMP to Epac1 and does not result in Rap1 activation. Functionally, PM accumulation of Epac1, an Epac1 mutant deficient in cAMP binding, or an Epac1 mutant tethered to the PM, is sufficient to inhibit neurite outgrowth. In conclusion, we uncover a cAMP-independent function of Epac1 at the PM and demonstrate that impβ1 controls subcellular localization of Epac1.
Exposure to extremely low frequency electromagnetic fields alters the behaviour, physiology and stress protein levels of desert locusts
Authors: Wyszkowska Joanna , Shepherd Sebastian , Sharkh Suleiman , Jackson Christopher W. , Newland Philip L.
Published: November 2016

Electromagnetic fields (EMFs) are present throughout the modern world and are derived from many man-made sources including overhead transmission lines. The risks of extremely-low frequency (ELF) electromagnetic fields are particularly poorly understood especially at high field strengths as they are rarely encountered at ground level. Flying insects, however, can approach close to high field strength transmission lines prompting the question as to how these high levels of exposure affect behaviour and physiology. Here we utilise the accessible nervous system of the locust to ask how exposure to high levels of ELF EMF impact at multiple levels. We show that exposure to ELF EMFs above 4 mT leads to reduced walking. Moreover, intracellular recordings from an identified motor neuron, the fast extensor tibiae motor neuron, show increased spike latency and a broadening of its spike in exposed animals. In addition, hind leg kick force, produced by stimulating the extensor tibiae muscle, was reduced following exposure, while stress-protein levels (Hsp70) increased. Together these results suggest that ELF EMF exposure has the capacity to cause dramatic effects from behaviour to physiology and protein expression, and this study lays the foundation to explore the ecological significance of these effects in other flying insects.
Raman spectroscopy and multivariate analysis for the non invasive diagnosis of clinically inconclusive vulval lichen sclerosus
Authors: Frost Jonathan , Ludeman Linmarie , Hillaby Kathryn , Gornall Robert , Lloyd Gavin , Kendall Catherine , Shore Angela C. , Stone Nick
Published: November 2016

The diagnostic performance of Raman spectroscopy for differentiating lichen sclerosus from other vulval conditions in fresh vulval biopsies is demonstrated.
Development of sensitive and selective glucose colorimetric assay using glucose oxidase immobilized on magnetite–gold–folate nanoparticles
Authors: Ponlakhet Kitayanan , Amatatongchai Maliwan , Sroysee Wongduan , Jarujamrus Purim , Chairam Sanoe
Published: November 2016

We constructed a new nanocomposite catalyst that demonstrated enzyme mimetic activity, like peroxidase, for the colorimetric detection of glucose.
Single-crystalline Pd square nanoplates enclosed by {100} facets on reduced graphene oxide for formic acid electro-oxidation
Authors: Jiang Yi , Yan Yucong , Chen Wenlong , Khan Yousaf , Wu Jianbo , Zhang Hui , Yang Deren
Published: November 2016

{100} faceted Pd nanoplates were prepared on reduced graphene oxide and exhibited substantially enhanced catalytic properties towards formic acid oxidation.
A deeper insight into an intriguing acetonitrile–water binary mixture: synergistic effect, dynamic Stokes shift, fluorescence correlation spectroscopy, and NMR studies
Authors: Koley Somnath , Ghosh Subhadip
Published: November 2016

An insight study reveals the strong synergistic solvation behaviours from reporter dye molecules within the acetonitrile (ACN)–water (WT) binary mixture.
Stabilizing effect of TMAO on globular PNIPAM states: preferential attraction induces preferential hydration
Authors: Schroer Martin A. , Michalowsky Julian , Fischer Birgit , Smiatek Jens , Grübel Gerhard
Published: November 2016

We study the effect of the organic co-solute trimethylamineN-oxide (TMAO) on the volume phase transition of microgel particles made from poly(N-isopropylacrylamide) (PNIPAM) using dynamic light scattering (DLS) and all-atom molecular dynamics (MD) simulations.
Electronic structure of the germanium phosphide monolayer and Li-diffusion in its bilayer
Authors: Shojaei Fazel , Kang Hong Seok
Published: November 2016

Based on the first-principles calculations, we predict that the monoclinic GeP can be exfoliated into two-dimensional (2D) monolayers.
Conductivity and phase morphology of carbon black-filled immiscible polymer blends under creep: an experimental and theoretical study
Authors: Pan Yamin , Liu Xianhu , Hao Xiaoqiong , Schubert Dirk W.
Published: November 2016

The simultaneous evolution of conductivity and phase morphology of blend composites was investigated under shear and in the quiescent state.
Enhanced photoelectrochemical water oxidation of bismuth vanadate via a combined strategy of W doping and surface RGO modification
Authors: Wan Xiaokang , Niu Fujun , Su Jinzhan , Guo Liejin
Published: November 2016

Combined modifications of tungsten doping and surface reduced graphene oxide modification enhance PEC water oxidation synergistically.
Enhanced perovskite morphology and crystallinity for high performance perovskite solar cells using a porous hole transport layer from polystyrene nanospheres
Authors: Zhang Fan , Song Jun , Chen Ming , Liu Junchen , Hao Yuying , Wang Yuncai , Qu Junle , Zeng Pengju
Published: November 2016

(1) Porous-PEDOT:PSS from PS nanospheres. (2) The perovskite quality is improved, with the improved crystallinity and enhanced grain sizes. (3) High-performance perovskite solar cells.
Conformational changes during permeation of Na+through a modified cyclic peptide nanotube promote energy landscape roughness
Authors: Alsina Marco A. , Gaillard Jean-François , Keten Sinan
Published: November 2016

Novel structure–function relations are observed during permeation of Na+through a cyclic peptide nanotube with functionalised interior.
Correction: The growing applications of click chemistry
Authors: Moses John E. , Moorhouse Adam D.
Published: November 2016

Correction for ‘The growing applications of click chemistry’ by John E. Moses et al., Chem. Soc. Rev., 2007, 36, 1249–1262.
Kinetic aspects of chain growth in Fischer–Tropsch synthesis
Authors: Filot Ivo A. W. , Zijlstra Bart , Broos Robin J. P. , Chen Wei , Pestman Robert , Hensen Emiel J. M.
Published: November 2016

Microkinetics simulations are used to investigate the elementary reaction steps that control chain growth in the Fischer–Tropsch reaction. Chain growth in the FT reaction on stepped Ru surfaces proceeds via coupling of CH and CR surface intermediates. Essential to the growth mechanism are C–H dehydrogenation and C hydrogenation steps, whose kinetic consequences have been examined by formulating two novel kinetic concepts, the degree of chain-growth probability control and the thermodynamic degree of chain-growth probability control. For Ru the CO conversion rate is controlled by the removal of O atoms from the catalytic surface. The temperature of maximum CO conversion rate is higher than the temperature to obtain maximum chain-growth probability. Both maxima are determined by Sabatier behavior, but the steps that control chain-growth probability are different from those that control the overall rate. Below the optimum for obtaining long hydrocarbon chains, the reaction is limited by the high total surface coverage: in the absence of sufficient vacancies the CHCHR → CCHR + H reaction is slowed down. Beyond the optimum in chain-growth probability, CHCR + H → CHCHR and OH + H → H2O limit the chain-growth process. The thermodynamic degree of chain-growth probability control emphasizes the critical role of the H and free-site coverage and shows that at high temperature, chain depolymerization contributes to the decreased chain-growth probability. That is to say, during the FT reaction chain growth is much faster than chain depolymerization, which ensures high chain-growth probability. The chain-growth rate is also fast compared to chain-growth termination and the steps that control the overall CO conversion rate, which are O removal steps for Ru.
Algae-mediated biosynthesis of inorganic nanomaterials as a promising route in nanobiotechnology – a review
Authors: Dahoumane Si Amar , Mechouet Mourad , Wijesekera Kushlani , Filipe Carlos D. M. , Sicard Clémence , Bazylinski Dennis A. , Jeffryes Clayton
Published: November 2016

This review presents an exhaustive and in-depth description of inorganic nanoparticle biosynthesis from photosynthetic organisms, known mechanisms and bio-applications.
Iodine-mediated C–N and C–S bond formation: regioselective synthesis of benzo[4,5]imidazo[2,1-b]thiazoles
Authors: Ambethkar Sethurajan , Vellimalai Muthalu , Padmini Vediappen , Bhuvanesh Nattamai
Published: November 2016

The regioselective synthesis of benzo[4,5]imidazo[2,1-b]thiazole derivatives via amination (C–N) and intramolecular cyclization (C–S) reactions in the presence of molecular iodine has been reported. This method is base and metal free and features inexpensive catalysts, with a simple procedure and a short reaction time.
Novel l-prolyl-l-leucylglycinamide (PLG) tripeptidomimetics based on a 2-azanorbornane scaffold as positive allosteric modulators of the D2R
Authors: Sampaio-Dias Ivo E. , Sousa Carlos A. D. , García-Mera Xerardo , Ferreira da Costa Joana , Caamaño Olga , Rodríguez-Borges José E.
Published: November 2016

Replacement of l-prolyl residue in the PLG sequence by an enantiopure (1R,3S,4S)-2-azanorbornane scaffold afforded active peptidomimetics compatible with suppression of the C-terminal carboxamide pharmacophore.
Direct observation and characterisation of 3-azido-2H-azirines: postulated, but highly elusive intermediates
Authors: Weigand Kevin , Singh Neeraj , Hagedorn Manfred , Banert Klaus
Published: November 2016

The title compounds, including the parent 3-azido-2H-azirine, were generated by low-temperature photolysis of the corresponding 1,1-diazidoethenes, and characterised not only by trapping reactions, but also by direct detection using NMR and in situ IR spectroscopy.
Growth of Mo2C nanoparticles on graphene as lubricant filler for high tribological performances of fabric self-lubricating liner composites
Authors: Yang Mingming , Zhang Zhaozhu , Yuan Junya , Guo Fang , Men Xuehu , Liu Weimin
Published: November 2016

In this article, Mo2C/graphene nanocomposites were synthesized by an in situ carburization of ammonium molybdate adsorbed on the surface of graphene oxide, and its tribological performances as a lubricant filler were systematically investigated.
Thermal behavior and electrochemistry of protic ionic liquids based on triethylamine with different acids
Authors: Shmukler L. E. , Gruzdev M. S. , Kudryakova N. O. , Fadeeva Yu. A. , Kolker A. M. , Safonova L. P.
Published: November 2016

Protic ionic liquids (PILs) composed of the triethylammonium cation with dihydrogen phosphite, tosylate, and trifluoroacetat anions were synthesized.
Robust AZO/i-ZnO bilayer front contact for high-performance thin film solar cells
Authors: Du Zhongming , Liu Xiangxin , Zhang Yufeng , Shuai Jiali , Li Hui
Published: November 2016

Resistivity of AZO/ZnO is lower than that of an AZO film after annealing at 400 °C for 60 minutes.
Influence of cysteine and bovine serum albumin on silver nanoparticle stability, dissolution, and toxicity to Phanerochaete chrysosporium
Authors: Yi Feng , Chen Guiqiu , Zeng Guangming , Guo Zhi , Liu Weiwei , Huang Zhenzhen , He Kai , Hu Liang
Published: November 2016

Cysteine (CYS) and bovine serum albumin (BSA) interact with silver nanoparticles (AgNPs) and influence its release, transportation, and toxicity.
A strategy for preparing spirobichroman dianhydride from bisphenol A and its resulting polyimide with low dielectric characteristic
Authors: Tang I Chun , Wang Meng Wei , Wu Chien Hsin , Dai Shenghong A. , Jeng Ru Jong , Lin Ching Hsuan
Published: November 2016

The high performance polyimide, SBC-DDM, exhibits a large free volume, leading to outstanding organo-solubility and a low dielectric constant.
Redox-mediated dissociation of PEG–polypeptide-based micelles for on-demand release of anticancer drugs
Authors: Wen Huiyun , Dong Haiqing , Liu Jie , Shen Aijun , Li Yongyong , Shi Donglu
Published: November 2016

The biocompatible polypeptide-based micelles that can rapidly disassemble for on-demand release of DOX under a redox environment are reported.
Electronics and optoelectronics of lateral heterostructures within monolayer indium monochalcogenides
Authors: Jin Hao , Li Jianwei , Wang Bin , Yu Yunjin , Wan Langhui , Xu Fuming , Dai Ying , Wei Yadong , Guo Hong
Published: November 2016

Lateral heterostructures have attracted a great deal of attention due to their advanced properties, which may open up unforeseen opportunities in materials science and device physics.
Gesundheit und medizinscher und psychosozialer Versorgungsbedarf von akuten oder ehemaligen Drogenabhängigen im Alter (40+) – Eine Querschnittstudie
Authors: Wehrwein A. , Schröder G. , Lindert J.
Published: November 2016

Hintergrund: Ziel dieser Studie war es, Gesundheit, gesundheitsbezogene Lebensqualität und den Wohn-, Hilfe- und Pflegebedarf älterer (ehemals) Drogenabhängiger zu erfassen sowie zu untersuchen, ob der Gesundheitszustand mit dem Wohn-, Unterstützungs- und Pflegebedarf assoziiert ist.

Methode: Zunächst wurde die Grundgesamtheit mittels capture-recapture Verfahren erhoben. Im zweiten Schritt wurde eine Einrichtungen-basierte Querschnittserhebung in Stuttgart (2014) durchgeführt. Erfasst wurden soziodemografische Daten, gesundheitsbezogene Lebensqualität (SF-36) sowie Erkrankungen, derzeitiger Wohn-, Unterstützungs- und Pflegebedarf (Fragebogen 50plushiv), und Substanzkonsum („European Addiction Severity Index“). Die Daten wurden uni-, bi- und multivariat analysiert.

Ergebnisse: N=37 Personen (30% Frauen) nahmen an der Studie teil (Responserate: 10,5%). 89% leiden an mindestens einer Erkrankung. Werte der allgemeinen Gesundheit (p=0,011), der Vitalität (p<0,001), der sozialen Funktionsfähigkeit (p<0,001), des psychischen Wohlbefindens (p<0,001) sowie der körperlichen Summenskala (p=0,007) und der psychischen Summenskala (p<0,001) liegen signifikant unter den Werten der altersspezifischen Normpopulation (51–60 Jahre). 54% haben derzeit einen Unterstützungsbedarf. Selbstständigkeit sowie fortgesetzter Substanzkonsum im Alter ist den Teilnehmerinnen am wichtigsten.

Schlussfolgerung: Gesundheitsbezogene Lebensqualität und insbesondere soziale Funktionsfähigkeit scheint bei älteren (ehemals) Drogenabhängigen reduziert zu sein. Dies zeigt die Notwendigkeit spezifische Versorgungskonzepte für ältere Drogenabhängige entsprechend dieser Ergebnisse zu gestalten. Zur Replizierung der Ergebnisse wäre eine repräsentative Langzeitstudie zur Erfassung des medizinischen und psychosozialen Versorgungsbedarfes älterer Drogenabhängiger notwendig.
Fluctuation conductivity due to the preformed local pairs
Authors: Domański T. , Barańska M. , Solovjov A. L.
Published: November 2016

We investigated the properties of a system where the itinerant electrons coexist and interact with the preformed local pairs. Using the nonperturbative continuous unitary transformation technique we show that Andreev-type scattering between these charge carriers gives rise to the enhanced diamagnetic response and is accompanied by appearance of the Drude peak inside the pseudogap regime ω≤2Δpg. Both effects are caused by the short-range superconducting correlations above the transition temperature Tc. In fact, the residual diamagnetism has been detected by the torque magnetometry in the lanthanum and bismuth cuprate superconductors at temperatures up to ∼1.5Tc. In this work we show how the superconducting correlations can be observed in the ac and dc conductivity.
Catalytic conversion in nanoporous materials: Concentration oscillations and spatial correlations due to inhibited transport and intermolecular interactions
Authors: García Andrés , Evans James W.
Published: November 2016

We show that steady-state catalytic conversion in nanoporous materials can occur in a quasi-counter-diffusion mode with the reactant (product) concentration strongly decaying (growing) into the pore, but also with oscillations in the total concentration. These oscillations reflect the response of the fluid to the transition from an extended to a confined environment near the pore opening. We focus on the regime of strongly inhibited transport in narrow pores corresponding to single-file diffusion. Here, limited penetration of the reactant into the pores and the associated low reaction yield is impacted by strong spatial correlations induced by both reaction (non-equilibrium correlations) and also by intermolecular interactions (thermodynamic correlations). We develop a generalized hydrodynamic formulation to effectively describe inhibited transport accounting for the effect of these correlations, and incorporate this description of transport into appropriate reaction-diffusion equations. These equations accurately describe both shorter-range concentration oscillations near the pore opening and the longer-range mesoscale variation of concentration profiles in the pore (and thus also describe reaction yield). Success of the analytic theory is validated by comparison with a precise kinetic Monte Carlo simulation of an appropriate molecular-level stochastic reaction-diffusion model. This work elucidates unconventional chemical kinetics in interacting confined systems.
Self-channelling of intense laser pulses in underdense plasma and stability analysis
Authors: Naseri N. , Rozmus W. , Pesme D.
Published: November 2016

Self-channelling of intense laser pulses have been studied in underdense plasma using three-dimensional particle-in-cell simulations, for different laser powers and plasma densities as well as analytical theory. It is found that single channel solution occurs for laser powers above the threshold power (∼1.1Pcr) and for plasma densities n<0.1ncr. For higher laser powers P>33Pcr, ring structure, an evacuated ring enclosed by electron filament, was observed in the simulations as predicted by analytical model. The stability of ring structure against symmetric and asymmetric azimuthal perturbations have been discussed.
Impurity detection in alkali-metal vapor cells via nuclear magnetic resonance
Authors: Patton B. , Ishikawa K.
Published: November 2016

We use nuclear magnetic resonance spectroscopy of alkali metals sealed in glass vapor cells to perform in situ identification of chemical contaminants. The alkali Knight shift varies with the concentration of the impurity, which in turn varies with temperature as the alloy composition changes along the liquidus curve. Intentional addition of a known impurity validates this approach and reveals that sodium is often an intrinsic contaminant in cells filled with distilled, high-purity rubidium or cesium. Measurements of the Knight shift of the binary Rb–Na alloy confirm prior measurements of the shift's linear dependence on Na concentration, but similar measurements for the Cs–Na system demonstrate an unexpected nonlinear dependence of the Knight shift on the molar ratio. This non-destructive approach allows monitoring and quantification of ongoing chemical processes within the kind of vapor cells which form the basis for precise sensors and atomic frequency standards.
Numerical investigation of 3D effects on a 2D-dominated shocked mixing layer
Authors: Reese Daniel , Weber Christopher
Published: November 2016

A nominally two-dimensional interface, unstable to the Rayleigh-Taylor or Richtmyer-Meshkov instability, will become three-dimensional at high Reynolds numbers due to the growth of background noise and 3D effects like vortex stretching. This three-dimensionality changes macroscopic features, such as the perturbation growth rate and mixing, as it enhances turbulent dissipation. In this study, a 2D perturbation with small-scale, 3D fluctuations is modeled using the hydrodynamics code Miranda. A Mach 1.95 shockwave accelerates a helium-over-SF6 interface, similar to the experiments of Motl et al. [“Experimental validation of a Richtmyer-Meshkov scaling law over large density ratio and shock strength ranges,” Phys. Fluids 21(12), 126102 (2009)], to explore the regime where a 2D dominated flow will experience 3D effects. We report on the structure, growth, and mixing of the post-shocked interface in 2D and 3D.
Ultrahigh-temperature rapid thermal oxidation of 4H-SiC(0001) surfaces and oxidation temperature dependence of SiO2/SiC interface properties
Authors: Hosoi Takuji , Nagai Daisuke , Sometani Mitsuru , Katsu Yoshihito , Takeda Hironori , Shimura Takayoshi , Takei Manabu , Watanabe Heiji
Published: November 2016

Ultrahigh-temperature rapid thermal oxidation of 4H-SiC(0001) surfaces in dry O2 ambient was performed at temperatures up to 1700 °C. The temperature dependence of the reaction-limited linear growth rate of a thermal SiO2 layer revealed that not active but passive oxidation is dominant even at 1600 °C, and its activation energy was estimated to be 2.9 eV. We also found that high-temperature oxidation is beneficial in improving SiO2/SiC interface properties, but unintentional oxidation during the cooling down process causes interface degradation. By effectively suppressing the oxide growth during the cooling process, the lowest interface state density was obtained for the oxide formed at 1450 °C.
Effect of double MgO tunneling barrier on thermal stability and TMR ratio for perpendicular MTJ spin-valve with tungsten layers
Authors: Lee Seung-Eun , Takemura Yasutaka , Park Jea-Gun
Published: November 2016

A tunneling magneto-resistance (TMR) ratio of ∼163% at an annealing temperature of 400 °C was achieved in a single MgO-based perpendicular-magnetic-tunneling-junction (p-MTJ) spin valve with a tungsten (W)/tantalum (Ta) seed and W capping layer instead of with a Ta seed and capping layer. This was done by improving the interface perpendicular magnetic anisotropy (i-PMA) characteristic of the Co2Fe6B2 free layer and face-centered-cubic (f.c.c.) crystallinity of the MgO tunneling barrier. In particular, a TMR ratio of ∼141% at an annealing temperature of 400 °C and a thermal stability at room temperature of ∼61 were achieved in a double MgO-based p-MTJ spin valve with W/Ta seed, W spacer, and W capping layers by doubling the i-PMA magnetic moment and increasing slightly magnetic anisotropy field (Hk).
Acoustic charge transport induced by the surface acoustic wave in chemical doped graphene
Authors: Zheng Shijun , Zhang Hao , Feng Zhihong , Yu Yuanyuan , Zhang Rui , Sun Chongling , Liu Jing , Duan Xuexin , Pang Wei , Zhang Daihua
Published: November 2016

A graphene/LiNbO3 hybrid device is used to investigate the acoustic induced charge transport in chemical doped graphene. The chemical doping of graphene via its physisorption of gas molecules affects the surface acoustic wave (SAW) charge carrier transport in a manner different from electric field drift. That transport induces doping dependent macroscopic acoustoelectric current. The chemical doping can manipulate majority carriers and induces unique acoustoelectric features. The observation is explained by a classical relaxation model. Eventually the device based on acoustoelectric current is proved to outperform the common chemiresistor for chemicals. Our finding provides insight into acoustic charge carrier transport during chemical doping. The doping affects interaction of carriers with SAW phonon and facilitates the understanding of nanoscale acoustoelectric effect. The exploration inspires potential acoustoelectric application for chemical detection involving emerging 2D nanomaterials.
Sodium antimony sulfide (NaSbS2): Turning an unexpected impurity into a promising, environmentally friendly novel solar absorber material
Authors: Rahayu Siti Utari , Chou Chia-Ling , Suriyawong Nipapon , Aragaw Belete Asefa , Shi Jen-Bin , Lee Ming-Way
Published: November 2016

We present a novel absorber material—NaSbS2—for solar cells. NaSbS2 is formed as an unexpected byproduct in the chemical synthesis of Sb2S3. However, NaSbS2 has many attractive features for a solar material. Here single phase NaSbS2 nanoparticles were synthesized through solution processing. NaSbS2 semiconductor-sensitized solar cells were demonstrated for the first time. The best cell yielded Jsc = 10.76 mA/cm2, Voc = 0.44 V, FF = 48.6%, and efficiency η = 2.30% under 1 sun. At the reduced 0.1 sun, the η increased to 3.18%—a respectable η for a new solar material.
Theoretical assessment of the disparity in the electrostatic forces between two point charges and two conductive spheres of equal radii
Authors: Kolikov Kiril
Published: November 2016

The Coulomb’s formula for the force FC of electrostatic interaction between two point charges is well known. In reality, however, interactions occur not between point charges, but between charged bodies of certain geometric form, size and physical structure. This leads to deviation of the estimated force FC from the real force F of electrostatic interaction, thus imposing the task to evaluate the disparity. In the present paper the problem is being solved theoretically for two charged conductive spheres of equal radii and arbitrary electric charges. Assessment of the deviation is given as a function of the ratio of the distance R between the spheres centers to the sum of their radii. For the purpose, relations between FC and F derived in a preceding work of ours, are employed to generalize the Coulomb’s interactions. At relatively short distances between the spheres, the Coulomb force FC, as estimated to be induced by charges situated at the centers of the spheres, differ significantly from the real force F of interaction between the spheres. In the case of zero and non-zero charge we prove that with increasing the distance between the two spheres, the force F decrease rapidly, virtually to zero values, i.e. it appears to be short-acting force.
Preparation and optimization of a molybdenum electrode for CIGS solar cells
Authors: Jingxue Feng , Zhao Wu , Wei Wang , Ye Yuan , Lin Zhuang , Xin Wang , Ruijiang Hong , Hui Shen , Chen Michael Z. Q.
Published: November 2016

Molybdenum (Mo) films were deposited by radio frequency (RF), direct current (DC) and mixed magnetron sputtering, respectively. With changing the deposition parameters including deposition pressure and power, the films show different surface morphology and crystallinity. Lower resistivity of the films is obtained in the DC mode and better reflectivity of the films is obtained in the RF mode. It is shown that the crystallinity increases when the deposition pressure decreases. The crystallinity and the grain size both increase as the deposition power increasing. The lowest resistivity of the single Mo film is 34×10-6 Ω·cm when the deposition pressure is 0.1 Pa and the deposition power is 300 W in the DC mode. In order to obtain lower resistivity, better adhesion and better reflectivity, bilayer films and tri-layer films were both deposited in different mode. They all show good adhesion and low resistivity. The Mo films deposited in mixed mode show better reflectivity. It is demonstrated that the resistivity of about 65×10-6 Ω·cm is achieved in DC/RF mode and the resistivity of about 61×10-6 Ω·cm is achieved in RF/DC/RF mode. And the tri-layer films achieved in RF/DC/RF mode have better reflectivity than bilayer films achieved in DC/RF mode. The tri-layer films achieved in RF/DC/RF mode is appropriate for using as the electrode of CIGS solar cells.
Putting David Craig’s Legacy to Work in Nanotechnology and Biotechnology
Authors: Reimers Jeffrey R.
Published: November 2016

David Craig (1919–2015) left us with a lasting legacy concerning basic understanding of chemical spectroscopy and bonding. This is expressed in terms of some of the recent achievements of my own research career, with a focus on integration of Craig’s theories with those of Noel Hush to solve fundamental problems in photosynthesis, molecular electronics (particularly in regard to the molecules synthesized by Maxwell Crossley), and self-assembled monolayer structure and function. Reviewed in particular is the relation of Craig’s legacy to: the 50-year struggle to assign the visible absorption spectrum of arguably the world’s most significant chromophore, chlorophyll; general theories for chemical bonding and structure extending Hush’s adiabatic theory of electron-transfer processes; inelastic electron-tunnelling spectroscopy (IETS); chemical quantum entanglement and the Penrose–Hameroff model for quantum consciousness; synthetic design strategies for NMR quantum computing; Gibbs free-energy measurements and calculations for formation and polymorphism of organic self-assembled monolayers on graphite surfaces from organic solution; and understanding the basic chemical processes involved in the formation of gold surfaces and nanoparticles protected by sulfur-bound ligands, ligands whose form is that of Au0-thiyl rather than its commonly believed AuI-thiolate tautomer.
Methanobactin transport machinery
Authors: Dassama Laura M. K. , Kenney Grace E. , Ro Soo Y. , Zielazinski Eliza L. , Rosenzweig Amy C.
Published: November 2016

Significance

Copper is central to the metabolism of methanotrophs, methane-oxidizing bacteria that are of interest because of their potential applications in bioremediation and bioconversion processes. Methanotrophs convert methane to methanol using particulate methane monooxygenase (pMMO), a copper-dependent, membrane-bound enzyme. To fulfill pMMO’s high requirement for copper, methanotrophs secrete and re-internalize methanobactin, a peptide-derived, copper-chelating natural product (CuMbn). Here we characterize the protein machinery used for import and periplasmic transport of CuMbn. These data provide important insights into the molecular mechanisms of CuMbn recognition and handling.