bluuebunny/crossref_metadata_2025 huggingface dataset:
Breeding ecology and success of a reintroduced population of the endangered Crested Ibis Nipponia nippon
Authors: YU XIAOPING , LI XIA , HUO ZHIPING
Published: December 2014

Reintroduction projects usually attempt to re-establish a self-sustaining population of endangered species within their historical ranges through the release of captive-bred individuals into the wild. We studied the breeding biology and nesting success of a reintroduced population of Crested Ibis Nipponia nippon in Ningshan County on the south slope of the Qinling Mountains of Shaannxi Province, China. From May 2007 to October 2011, 56 captive-bred individuals, composed of 26 females and 30 males, were released into the area and monitored using radio-telemetry. The average age of individuals at release was 5.2 ± 2.5 years for females and 6.4 ± 2.9 years for males. Mean clutch size was 3.14±1.06 (range 1-5). Mean number of fledglings per active nest was 1.57 ± 1.03 and mean number of fledglings per successful nest was 2.00 ± 0.87. Most of the fledglings survived to complete their post-fledging dispersal. Mean annual survival rate was 0.552 ± 0.064 for all released birds, 0.815 ± 0.054 for breeders, and 0.515 ± 0.058 for first year fledglings. The average number of young produced/year/pair was 1.57 ± 1.03 and the growth rate (λ) of the reintroduced population was 1.2193. We confirmed that starvation and predation by King Rat Snake Elaphe carinata were the main causes of death of released individuals, nestlings and fledglings. This is the first attempt to reintroduce captive-bred Crested Ibis to former natural habitat. The ability of captive-bred ibis to survive and breed successfully bodes well for future releases of this and other endangered species.
Formulae and Asymptotics for Coefficients of Algebraic Functions
Authors: BANDERIER CYRIL , DRMOTA MICHAEL
Published: December 2014

We study the coefficients of algebraic functions ∑n≥0fnzn. First, we recall the too-little-known fact that these coefficientsfnalways admit a closed form. Then we study their asymptotics, known to be of the typefn~CAnnα. When the function is a power series associated to a context-free grammar, we solve a folklore conjecture: the critical exponents α cannot be 1/3 or −5/2; they in fact belong to a proper subset of the dyadic numbers. We initiate the study of the set of possible values forA. We extend what Philippe Flajolet called the Drmota–Lalley–Woods theorem (which states that α=−3/2 when the dependency graph associated to the algebraic system defining the function is strongly connected). We fully characterize the possible singular behaviours in the non-strongly connected case. As a corollary, the generating functions of certain lattice paths and planar maps are not determined by a context-free grammar (i.e., their generating functions are not ℕ-algebraic). We give examples of Gaussian limit laws (beyond the case of the Drmota–Lalley–Woods theorem), and examples of non-Gaussian limit laws. We then extend our work to systems involving non-polynomial entire functions (non-strongly connected systems, fixed points of entire functions with positive coefficients). We give several closure properties for ℕ-algebraic functions. We end by discussing a few extensions of our results (infinite systems of equations, algorithmic aspects).
Blocking autophagy enhanced cytotoxicity induced by recombinant human arginase in triple-negative breast cancer cells
Authors: Wang Z , Shi X , Li Y , Fan J , Zeng X , Xian Z , Wang Z , Sun Y , Wang S , Song P , Zhao S , Hu H , Ju D
Published: December 2014

Depletion of arginine by recombinant human arginase (rhArg) has proven to be an effective cancer therapeutic approach for a variety of malignant tumors. Triple-negative breast cancers (TNBCs) lack of specific therapeutic targets, resulting in poor prognosis and limited therapeutic efficacy. To explore new therapeutic approaches for TNBC we studied the cytotoxicity of rhArg in five TNBC cells. We found that rhArg could inhibit cell growth in these five TNBC cells. Intriguingly, accumulation of autophagosomes and autophagic flux was observed in rhArg-treated MDA-MB-231 cells. Inhibition of autophagy by chloroquine (CQ), 3-methyladenine (3-MA) and siRNA targeting Beclin1 significantly enhanced rhArg-induced cytotoxic effect, indicating the cytoprotective role of autophagy in rhArg-induced cell death. In addition, N-acetyl-l-cysteine (NAC), a common antioxidant, blocked autophagy induced by rhArg, suggesting that reactive oxygen species (ROS) had an essential role in the cytotoxicity of rhArg. This study provides new insights into the molecular mechanism of autophagy involved in rhArg-induced cytotoxicity in TNBC cells. Meanwhile, our results revealed that rhArg, either alone or in combination with autophagic inhibitors, might be a potential novel therapy for the treatment of TNBC.
A loss of FUS/TLS function leads to impaired cellular proliferation
Authors: Ward C L , Boggio K J , Johnson B N , Boyd J B , Douthwright S , Shaffer S A , Landers J E , Glicksman M A , Bosco D A
Published: December 2014

Fused in sarcoma/translocated in liposarcoma (FUS/TLS or FUS) is a multifunctional RNA/DNA-binding protein that is pathologically associated with cancer and neurodegeneration. To gain insight into the vital functions of FUS and how a loss of FUS function impacts cellular homeostasis, FUS expression was reduced in different cellular models through RNA interference. Our results show that a loss of FUS expression severely impairs cellular proliferation and leads to an increase in phosphorylated histone H3, a marker of mitotic arrest. A quantitative proteomics analysis performed on cells undergoing various degrees of FUS knockdown revealed protein expression changes for known RNA targets of FUS, consistent with a loss of FUS function with respect to RNA processing. Proteins that changed in expression as a function of FUS knockdown were associated with multiple processes, some of which influence cell proliferation including cell cycle regulation, cytoskeletal organization, oxidative stress and energy homeostasis. FUS knockdown also correlated with increased expression of the closely related protein EWS (Ewing’s sarcoma). We demonstrate that the maladaptive phenotype resulting from FUS knockdown is reversible and can be rescued by re-expression of FUS or partially rescued by the small-molecule rolipram. These results provide insight into the pathways and processes that are regulated by FUS, as well as the cellular consequences for a loss of FUS function.
Regulation of caspase-3 processing by cIAP2 controls the switch between pro-inflammatory activation and cell death in microglia
Authors: Kavanagh E , Rodhe J , Burguillos M A , Venero J L , Joseph B
Published: December 2014

The activation of microglia, resident immune cells of the central nervous system, and inflammation-mediated neurotoxicity are typical features of neurodegenerative diseases, for example, Alzheimer's and Parkinson's diseases. An unexpected role of caspase-3, commonly known to have executioner role for apoptosis, was uncovered in the microglia activation process. A central question emerging from this finding is what prevents caspase-3 during the microglia activation from killing those cells? Caspase-3 activation occurs as a two-step process, where the zymogen is first cleaved by upstream caspases, such as caspase-8, to form intermediate, yet still active, p19/p12 complex; thereafter, autocatalytic processing generates the fully mature p17/p12 form of the enzyme. Here, we show that the induction of cellular inhibitor of apoptosis protein 2 (cIAP2) expression upon microglia activation prevents the conversion of caspase-3 p19 subunit to p17 subunit and is responsible for restraining caspase-3 in terms of activity and subcellular localization. We demonstrate that counteracting the repressive effect of cIAP2 on caspase-3 activation, using small interfering RNA targeting cIAP2 or a SMAC mimetic such as the BV6 compound, reduced the pro-inflammatory activation of microglia cells and promoted their death. We propose that the different caspase-3 functions in microglia, and potentially other cell types, reside in the active caspase-3 complexes formed. These results also could indicate cIAP2 as a possible therapeutic target to modulate microglia pro-inflammatory activation and associated neurotoxicity observed in neurodegenerative disorders.
Heme oxygenase-1 protects against Alzheimer’s amyloid-β1-42-induced toxicity via carbon monoxide production
Authors: Hettiarachchi N , Dallas M , Al-Owais M , Griffiths H , Hooper N , Scragg J , Boyle J , Peers C
Published: December 2014

Heme oxygenase-1 (HO-1), an inducible enzyme up-regulated in Alzheimer’s disease, catabolises heme to biliverdin, Fe2+ and carbon monoxide (CO). CO can protect neurones from oxidative stress-induced apoptosis by inhibiting Kv2.1 channels, which mediates cellular K+ efflux as an early step in the apoptotic cascade. Since apoptosis contributes to the neuronal loss associated with amyloid β peptide (Aβ) toxicity in AD, we investigated the protective effects of HO-1 and CO against Aβ1-42 toxicity in SH-SY5Y cells, employing cells stably transfected with empty vector or expressing the cellular prion protein, PrPc, and rat primary hippocampal neurons. Aβ1-42 (containing protofibrils) caused a concentration-dependent decrease in cell viability, attributable at least in part to induction of apoptosis, with the PrPc-expressing cells showing greater susceptibility to Aβ1-42 toxicity. Pharmacological induction or genetic over-expression of HO-1 significantly ameliorated the effects of Aβ1-42. The CO-donor CORM-2 protected cells against Aβ1-42 toxicity in a concentration-dependent manner. Electrophysiological studies revealed no differences in the outward current pre- and post-Aβ1-42 treatment suggesting that K+ channel activity is unaffected in these cells. Instead, Aβ toxicity was reduced by the L-type Ca2+ channel blocker nifedipine, and by the CaMKKII inhibitor, STO-609. Aβ also activated the downstream kinase, AMP-dependent protein kinase (AMPK). CO prevented this activation of AMPK. Our findings indicate that HO-1 protects against Aβ toxicity via production of CO. Protection does not arise from inhibition of apoptosis-associated K+ efflux, but rather by inhibition of AMPK activation, which has been recently implicated in the toxic effects of Aβ. These data provide a novel, beneficial effect of CO which adds to its growing potential as a therapeutic agent.
XIAP-targeting drugs re-sensitize PIK3CA-mutated colorectal cancer cells for death receptor-induced apoptosis
Authors: Ehrenschwender M , Bittner S , Seibold K , Wajant H
Published: December 2014

Mutations in the oncogenic PIK3CA gene are found in 10–20% of colorectal cancers (CRCs) and are associated with poor prognosis. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and agonistic TRAIL death receptor antibodies emerged as promising anti-neoplastic therapeutics, but to date failed to prove their capability in the clinical setting as especially primary tumors exhibit high rates of TRAIL resistance. In our study, we investigated the molecular mechanisms underlying TRAIL resistance in CRC cells with a mutant PIK3CA (PIK3CA-mut) gene. We show that inhibition of the constitutively active phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway only partially overcame TRAIL resistance in PIK3CA-mut-protected HCT116 cells, although synergistic effects of TRAIL plus PI3K, Akt or cyclin-dependent kinase (CDK) inhibitors could be noted. In sharp contrast, TRAIL triggered full-blown cell death induction in HCT116 PIK3CA-mut cells treated with proteasome inhibitors such as bortezomib and MG132. At the molecular level, resistance of HCT116 PIK3CA-mut cells against TRAIL was reflected by impaired caspase-3 activation and we provide evidence for a crucial involvement of the E3-ligase X-linked inhibitor of apoptosis protein (XIAP) therein. Drugs interfering with the activity and/or the expression of XIAP, such as the second mitochondria-derived activator of caspase mimetic BV6 and mithramycin-A, completely restored TRAIL sensitivity in PIK3CA-mut-protected HCT116 cells independent of a functional mitochondrial cell death pathway. Importantly, proteasome inhibitors and XIAP-targeting agents also sensitized other CRC cell lines with mutated PIK3CA for TRAIL-induced cell death. Together, our data suggest that proteasome- or XIAP-targeting drugs offer a novel therapeutic approach to overcome TRAIL resistance in PIK3CA-mutated CRC.
Transformation of intestinal stem cells into gastric stem cells on loss of transcription factor Cdx2
Authors: Simmini Salvatore , Bialecka Monika , Huch Meritxell , Kester Lennart , van de Wetering Marc , Sato Toshiro , Beck Felix , van Oudenaarden Alexander , Clevers Hans , Deschamps Jacqueline
Published: December 2014

The endodermal lining of the adult gastro-intestinal tract harbours stem cells that are responsible for the day-to-day regeneration of the epithelium. Stem cells residing in the pyloric glands of the stomach and in the small intestinal crypts differ in their differentiation programme and in the gene repertoire that they express. Both types of stem cells have been shown to grow from single cells into 3D structures (organoids) in vitro. We show that single adult Lgr5-positive stem cells, isolated from small intestinal organoids, require Cdx2 to maintain their intestinal identity and are converted cell-autonomously into pyloric stem cells in the absence of this transcription factor. Clonal descendants of Cdx2null small intestinal stem cells enter the gastric differentiation program instead of producing intestinal derivatives. We show that the intestinal genetic programme is critically dependent on the single transcription factor encoding gene Cdx2.
Influence of MoO3(110) Crystalline Plane on Its Self-Charging Photoelectrochemical Properties
Authors: Lou Shi Nee , Yap Nicholas , Scott Jason , Amal Rose , Ng Yun Hau
Published: December 2014

Nanocrystalline molybdenum oxide (α-MoO3) thin films with iso-oriented crystalline layers were synthesised by the anodisation of Mo foils. Upon band-gap excitation using light illumination, α-MoO3 generates excited electrons for reductive reactions and stores some of the excited electrons in its layered crystalline structure via alkali cation intercalation. These stored electrons can be subsequently discharged from α-MoO3 to allow reductive reactions to continue to occur under non-illuminated conditions. The modulation of water concentrations in the organic/aqueous anodisation electrolytes readily produces α-MoO3 crystals with high degree of (kk0) crystallographic orientation. Moreover, these (kk0)-oriented MoO3 crystals exhibit well-developed {hk0} and {0k0} crystal facets. In this paper, we show the benefits of producing α-MoO3 thin films with defined crystal facets and an iso-oriented layered structure for in situ storing of excited charges. α-MoO3 crystals with dominant (kk0) planes can achieve fast charging and a strong balance between charge release for immediate exploitation under illuminated conditions and charge storage for subsequent utilisation in dark. In comparison, α-MoO3 crystals with dominant (0k0) planes show a preference for excited charge storage.
Evolutionary Importance of the Intramolecular Pathways of Hydrolysis of Phosphate Ester Mixed Anhydrides with Amino Acids and Peptides
Authors: Liu Ziwei , Beaufils Damien , Rossi Jean-Christophe , Pascal Robert
Published: December 2014

Aminoacyl adenylates (aa-AMPs) constitute essential intermediates of protein biosynthesis. Their polymerization in aqueous solution has often been claimed as a potential route to abiotic peptides in spite of a highly efficient CO2-promoted pathway of hydrolysis. Here we investigate the efficiency and relevance of this frequently overlooked pathway from model amino acid phosphate mixed anhydrides including aa-AMPs. Its predominance was demonstrated at CO2 concentrations matching that of physiological fluids or that of the present-day ocean, making a direct polymerization pathway unlikely. By contrast, the occurrence of the CO2-promoted pathway was observed to increase the efficiency of peptide bond formation owing to the high reactivity of the N-carboxyanhydride (NCA) intermediate. Even considering CO2 concentrations in early Earth liquid environments equivalent to present levels, mixed anhydrides would have polymerized predominantly through NCAs. The issue of a potential involvement of NCAs as biochemical metabolites could even be raised. The formation of peptide–phosphate mixed anhydrides from 5(4H)-oxazolones (transiently formed through prebiotically relevant peptide activation pathways) was also observed as well as the occurrence of the reverse cyclization process in the reactions of these mixed anhydrides. These processes constitute the core of a reaction network that could potentially have evolved towards the emergence of translation.
Synthesis and characterization of diphenyl–phenyl polysiloxane as a high-temperature gas chromatography stationary phase
Authors: Zhao Pengchao , Teng Shuang , Yu Miao , Niu Na , He Xinxin , Wu Bo
Published: December 2014

Diphenyl–phenyl polysiloxane (DPPP) was synthesized and used as a high-temperature gas chromatography stationary phase, which has a great potential in the analysis of substituted benzene and PAHs.
Redox hydrogel based immunosensing platform for the label-free detection of a cancer biomarker
Authors: Huang Yaxun , Ding Yingying , Li Ting , Yang Minghui
Published: December 2014

Image of the synthesized hydrogel and square wave voltammetry (SWV) response of the immunosensor to different concentrations of PSA.
The transfection efficiency of calix[4]arene-based lipids: the role of the alkyl chain length
Authors: Mochizuki Shinichi , Nishina Koichi , Fujii Shota , Sakurai Kazuo
Published: December 2014

Calix[4]arene-based lipids with the C6 alkyl chain length exhibited the highest transfection efficiency among all lipoplexes comprising the lipids with different alkyl chain lengths and plasmid DNA.
Recent advances in targeted drug delivery approaches using dendritic polymers
Authors: Bugno Jason , Hsu Hao-jui , Hong Seungpyo
Published: December 2014

Synthesis of dendrimers and their modified nanoparticles.
Photobiocatalytic decarboxylation for olefin synthesis
Authors: Zachos Ioannis , Gaßmeyer Sarah Katharina , Bauer Daniel , Sieber Volker , Hollmann Frank , Kourist Robert
Published: December 2014

The oxidative decarboxylation of fatty acids to terminal alkenes was accomplished with high selectivity by combining a fatty acid decarboxylase OleTJE with the light-catalyzed generation of the cosubstrate hydrogen peroxide, resulting in a simple and efficient system for the light-driven cleavage of C–C bonds.
Topological ring-currents and bond-currents in the altan-[r,s]-coronenes
Authors: Dickens T. K. , Mallion R. B.
Published: December 2014

π-Electron ring-currents for the altans of the four regular [r,s]-coronenes are calculated by the topological HLPM approach.
Controlled and sustained release of pharmaceuticals via single step solvent-free encapsulation
Authors: Cavallaro A. , Vasilev K.
Published: December 2014

Herein, we report a novel and solvent-free technique for the encapsulation of pharmaceuticals that allows achieving controllable release rates.
Cu-Catalyzed selective C3-formylation of imidazo[1,2-a]pyridine C–H bonds with DMSO using molecular oxygen
Authors: Cao Hua , Lei Sai , Li Naiying , Chen Longbin , Liu Jingyun , Cai Huiyin , Qiu Shuxian , Tan Jingwen
Published: December 2014

Using the widely available DMSO as the formylation reagent under oxidative conditions, an efficient Cu-catalyzed C3-formylation reaction of imidazo [1,2-a]pyridine C–H bonds to directly generate structurally sophisticated 3-formyl imidazo[1,2-a]pyridine derivatives has been developed.
Synthesis, structure and dehydrogenation of zirconium borohydride octaammoniate
Authors: Huang Jianmei , Tan Yingbin , Su Jiahao , Gu Qinfen , Černý Radovan , Ouyang Liuzhang , Sun Dalin , Yu Xuebin , Zhu Min
Published: December 2014

A novel metal borohydride ammoniate (MBA), Zr(BH4)4·8NH3, has a distinctive structure and the highest ammonia coordination number among all the known MBAs.
Radiolysis of crown ether–ionic liquid systems: identification of radiolytic products and their effect on the removal of Sr2+ from nitric acid
Authors: Ao Yinyong , Yuan Weijin , Yu Tianlin , Peng Jing , Li Jiuqiang , Zhai Maolin , Zhao Long
Published: December 2014

The quantitative analysis and identification of the radiolytic products of dicyclohexano-18-crown-6 (DCH18C6), 4′,4′′(5′′)-di-tert-butyldicyclohexano-18-crown-6 (DtBuCH18C6) and benzo-18-crown-6 (B18C6) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([C4mim][NTf2]) ionic liquid after irradiation were performed for the first time.
Go natural and smarter: fenugreek as a hydration designer of collagen based biomaterials
Authors: Kanungo Ivy , Fathima Nishter Nishad , Jonnalagadda Raghava Rao , Nair Balachandran Unni
Published: December 2014

A facile and convenient strategy to design the solvation network of collagen, using fenugreek has been investigated. This can be explored for the smart biomaterial applications.
Controlled direct growth of Al2O3-doped HfO2 films on graphene by H2O-based atomic layer deposition
Authors: Zheng Li , Cheng Xinhong , Yu Yuehui , Xie Yahong , Li Xiaolong , Wang Zhongjian
Published: December 2014

Al2O3-doped HfO2 with both amorphous state and high relative permittivity was directly deposited on graphene by atomic layer deposition.
Magnetic and microwave absorption properties of self-assemblies composed of core–shell cobalt–cobalt oxide nanocrystals
Authors: Wang Zhongzhu , Bi Hong , Wang Peihong , Wang Min , Liu Zhiwei , shen Lei , Liu Xiansong
Published: December 2014

We adopt a simple method to synthesize core–shell cobalt–cobalt oxide nanocrystals, presenting the enhanced microwave absorption properties.
Exploring the binding mechanisms of MIF to CXCR2 using theoretical approaches
Authors: Xu Lei , Li Youyong , Li Dan , Xu Peng , Tian Sheng , Sun Huiyong , Liu Hui , Hou Tingjun
Published: December 2014

Macrophage migration inhibitory factor (MIF) is a multi-functional protein that acts as a cytokine and an enzyme.
Preparation, characterization, and properties of PMMA-doped polymer film materials: a study on the effect of terbium ions on luminescence and lifetime enhancement
Authors: Zhang Hui-Jie , Fan Rui-Qing , Wang Xin-Ming , Wang Ping , Wang Yu-Lei , Yang Yu-Lin
Published: December 2014

CdCl2 type Tb coordination polymers have significant effects on luminescence properties and thermal stability when used to dope a PMMA matrix.
Bi2Te(IO3)O5Cl: a novel polar iodate oxychloride exhibiting a second-order nonlinear optical response
Authors: Geng Lei , Meng Changyu , Lu Hongyan , Luo Zhongzhen , Lin Chensheng , Cheng Wendan
Published: December 2014

A novel iodate oxychloride Bi2Te(IO3)O5Cl with a second-order nonlinear optical response originating from constructive stacking of dipole moments of IO3.
BaCu2Se2 based compounds as promising thermoelectric materials
Authors: Li Jing , Zhao Li-Dong , Sui Jiehe , Berardan David , Cai Wei , Dragoe Nita
Published: December 2014

The thermoelectric properties of Na doped BaCu2Se2 were studied. The electrical conductivity of BaCu2Se2 was increased by 2 orders of magnitude through Na doping at the Ba sites, combined with a surprisingly low thermal conductivity; a ZT of 1.0 has been obtained for Ba0.925Na0.075Cu2Se2 at 773 K.
Formation of disinfection byproducts in a recirculating mariculture system: emerging concerns
Authors: Qiang Zhimin , Zhang Haiting , Dong Huiyu , Adams Craig , Luan Gang , Wang Lei
Published: December 2014

The formation of various kinds of DBPs in marine aquaria raises serious concerns because of their threat to the health of aquarium animals.
Prioritizing candidate disease-related long non-coding RNAs by walking on the heterogeneous lncRNA and disease network
Authors: Zhou Meng , Wang Xiaojun , Li Jiawei , Hao Dapeng , Wang Zhenzhen , Shi Hongbo , Han Lu , Zhou Hui , Sun Jie
Published: December 2014

Accumulated evidence has shown that long non-coding RNAs (lncRNA) act as a widespread layer in gene regulatory networks and are involved in a wide range of biological processes.
Identification and molecular structure analysis of a new noncoding RNA, a sbRNA homolog, in the silkworm Bombyx mori genome
Authors: Duarte Junior Francisco Ferreira , Lima Neto Quirino Alves de , Rando Fabiana dos Santos , Freitas Douglas Vinícius Bassalobre de , Pattaro Júnior José Renato , Polizelli Lorena Gomes , Munhoz Roxelle Ethienne Ferreira , Seixas Flavio Augusto Vicente , Fernandez Maria Aparecida
Published: December 2014

Bioinformatic tools and PCR expression experiments were used to identify a new noncoding RNA homologous to sbRNA in theBombyx morigenome.
Naturally occurring FANCF–Hes1 complex inhibitors from Wrightia religiosa
Authors: Arai Midori A. , Uemura Kenji , Hamahiga Nozomi , Ishikawa Naoki , Koyano Takashi , Kowithayakorn Thaworn , Kaddar Tagrid , Carreau Madeleine , Ishibashi Masami
Published: December 2014

The first naturally occurring inhibitors of FANCF–Hes1 complex were isolated by a newly constructed protein-based high-throughput screening assay.
Bioinspired nanovalves with selective permeability and pH sensitivity
Authors: Zheng Z. , Huang X. , Schenderlein M. , Moehwald H. , Xu G.-K. , Shchukin D. G.
Published: December 2014

Nuclear pore complexes, as an effective valve system, inspired the design of nanovalves for controlled release of angstrom-sized molecules that can form strong but reversible complex bonding with valve structure. While for other cargo molecules, only size-dependent diffusion through the nanovalves can be seen.
Genotoxicity of metal oxide nanomaterials: review of recent data and discussion of possible mechanisms
Authors: Golbamaki Nazanin , Rasulev Bakhtiyor , Cassano Antonio , Marchese Robinson Richard L. , Benfenati Emilio , Leszczynski Jerzy , Cronin Mark T. D.
Published: December 2014

An increasing number of publications report genotoxicity studies for metal oxide and silica nanomaterials which may induce different kinds of genotoxicityviaa variety of mechanisms.
Synthetic strategy for preparing chiral double-semicrystalline polyether block copolymers
Authors: McGrath Alaina J. , Shi Weichao , Rodriguez Christina G. , Kramer Edward J. , Hawker Craig J. , Lynd Nathaniel A.
Published: December 2014

A practical synthetic strategy for the preparation of isotactic inverse pluronic structures was developed, leading to new double-semicrystalline materials.
Particle clustering during pearl chain formation in a conductive-island based dielectrophoretic assembly system
Authors: Ding Haitao , Liu Weiyu , Ding Yucheng , Shao Jinyou , Zhang Liangliang , Liu Peichang , Liu Hongzhong
Published: December 2014

Particle clustering during pearl chain formation in a conductive-island based dielectrophoretic assembly system.
Curcumin-p-sulfonatocalix[4]resorcinarene (p-SC[4]R) interaction: thermo-physico chemistry, stability and biological evaluation
Authors: Valand Nikunj N. , Patel Manishkumar B. , Menon Shobhana K.
Published: December 2014

The target to enhance the solubility, bioavailability, stability and anti-oxidant activity, as well as the decrease in the acute oral toxicity of curcumin by 1 : 1 curcumin–p-SC[4]Rinclusion complexation.
Enhanced electrochemical sensing of polyphenols by an oxygen-mediated surface
Authors: Gusmão Rui , López-Puente Vanesa , Pastoriza-Santos Isabel , Pérez-Juste Jorge , Proença Maria Fernanda , Bento Fátima , Geraldo Dulce , Paiva Maria Conceição , González-Romero Elisa
Published: December 2014

We report a straightforward heat treatment in air of commercial screen-printed carbon electrodes (SPCE) at different temperatures and times (ht-SPCE) that produces considerable electrocatalytic effects.
Near-infrared light-controlled drug release and cancer therapy with polymer-caged upconversion nanoparticles
Authors: Xing Qingjian , Li Najun , Jiao Yang , Chen Dongyun , Xu Jiaying , Xu Qingfeng , Lu Jianmei
Published: December 2014

The core–shell nanocarrier, based on spiropyran-containing copolymer coated upconversion nanocomposites, was successfully prepared via a facile self-assembly process for NIR-triggered drug release and cancer therapy.
Efficient synthesis of quinazoline-2,4(1H,3H)-diones from CO2 catalyzed by N-heterocyclic carbene at atmospheric pressure
Authors: Xiao Yunqing , Kong Xianqiang , Xu Zhicheng , Cao Changsheng , Pang Guangsheng , Shi Yanhui
Published: December 2014

Under atmospheric pressure, quinazoline-2,4(1H,3H)-diones were obtained from the reaction of 2-aminobenzonitriles with carbon dioxide (0.1 MPa) with a catalytic amount of N-heterocyclic carbene in DMSO.
On the hunt for truly biocompatible ionic liquids for lipase-catalyzed reactions
Authors: Deive Francisco J. , Ruivo Diana , Rodrigues João V. , Gomes Cláudio M. , Sanromán M. Ángeles , Rebelo Luís Paulo N. , Esperança José M. S. S. , Rodríguez Ana
Published: December 2014

One of the challenges in the field of biocatalysis is the search for efficient reaction media avoiding enzyme deactivation.
Design and fabrication of carbon fiber/carbonyl iron core–shell structure composites as high-performance microwave absorbers
Authors: Yuan Liu , Xiangxuan Liu , Rong Li , Wu Wen , Xuanjun Wang
Published: December 2014

Carbon fiber/carbonyl iron core–shell structure composites with excellent microwave absorbing performance were prepared by a metal organic chemical vapor deposition process.
Gold-supported magnetically recyclable nanocatalysts: a sustainable solution for the reduction of 4-nitrophenol in water
Authors: Rocha Mariana , Fernandes Carlos , Pereira Clara , Rebelo Susana L. H. , Pereira Manuel F. R. , Freire Cristina
Published: December 2014

Magnetic core-double shell silica nanosupports functionalized with amine and thiol groups successfully immobilized Au NPs, producing novel magnetically recyclable nanocatalysts for the reduction of 4-nitrophenol in water in the presence of NaBH4.
Tetraphenylpyrazine-based AIEgens: facile preparation and tunable light emission
Authors: Chen Ming , Li Lingzhi , Nie Han , Tong Jiaqi , Yan Lulin , Xu Bin , Sun Jing Zhi , Tian Wenjing , Zhao Zujin , Qin Anjun , Tang Ben Zhong
Published: December 2014

Structurally new AIEgens with tunable emission based on tetraphenylpyrazine were rationally designed and readily prepared.
Fixing of highly soluble Br2/Br− in porous carbon as a cathode material for rechargeable lithium ion batteries
Authors: Wang Y. L. , Wang X. , Tian L. Y. , Sun Y. Y. , Ye Shi-hai
Published: December 2014

LiBr, as a representative of high soluble electrochemical active materials, is fixed in nanopores of conductive carbon black (CCB). The Li/LiBr–CCB battery presents excellent high-rate capability for avoiding the slow solid-phase diffusion of Li ions in traditional solid cathode materials.
Vulcanization accelerator enabled sulfurized carbon materials for high capacity and high stability of lithium–sulfur batteries
Authors: Chen Hongwei , Wang Changhong , Hu Chenji , Zhang Jiansheng , Gao Shan , Lu Wei , Chen Liwei
Published: December 2014

Borrowing the idea from rubber cross linking chemistry, we report the use of a vulcanization accelerator in carbon sulfurization. The resulting Li–S battery exhibits a remarkable increase in discharge capacity while maintaining its outstanding cycling stability and low self-discharge.
A polyaniline microtube platform for direct electron transfer of glucose oxidase and biosensing applications
Authors: Zhang Lei , Zhou Cuisong , Luo Jiaojiao , Long Yuyin , Wang Congmin , Yu Tingting , Xiao Dan
Published: December 2014

A polyaniline microtube platform was fabricated for direct electron transfer of glucose oxidase and biosensing applications.
Performance of a cooperative downlink multiplexing scheme using dynamic spectrum access principles
Authors: Verma Dileep Kumar , Prakriya Shankar
Published: December 2014

In this study, the authors propose a new cooperative multiplexing scheme for downlink transmission using dynamic spectrum access (DSA) principles. In this scheme, the base‐station (BS) transmits to its distant user using a selected relay node in two hops. In the second hop, while the relay forwards information to the distant user, the BS transmits information to another selected user in its vicinity using DSA principles. Assuming peak power and peak interference constraints, the authors derive outage and ergodic rate performance of the user served by DSA assuming various user selection schemes. The authors consider gain‐based selection, SINR based selection (SS), interference cancellation (IC), as well as a hybrid scheme that employs both SS and IC. The authors demonstrate that apportioning of time between the first and second hop of relaying can improve outage performance of the user served by DSA while ensuring certain guaranteed performance for the distant user. The presented analytical expressions are compared with computer simulation results.
Outage probability of device‐to‐device communication assisted by one‐way amplify‐and‐forward relaying
Authors: Ni Yiyang , Wang Xiaoyu , Jin Shi , Wong Kai‐Kit , Zhu Hongbo , Zhang Naitong
Published: December 2014

This study investigates the outage probability of device‐to‐device communication assisted by a relay node utilising a one‐way amplify‐and‐forward relaying strategy. The authors assume that all the terminals are equipped with a single antenna and all the users know perfect channel state information. They first derive the exact closed‐form expression for characterising the outage probability performance of the system. They subsequently discuss several special scenarios and obtain the asymptotic results for each of the considered scenarios. The results can be easily computed with only the channel statistics. Based on the analysis in the high signal‐to‐noise ratio regime, closed‐form power allocation policies are developed to improve the outage probability performance. The author's analytical results are validated via Monte Carlo computer simulations.
Modelling of dual three‐phase permanent magnet brushless machine and drive using matrix and tensor approach
Authors: Luo Zhanqiang , Liang Deliang , Ding Wen
Published: December 2014

The advent of electrically powered actuation system (EPAS) promises improved reliability, controllability and efficiency as well as reduced maintenance in high‐power applications that have historically been serviced by hydraulic systems. Dual three‐phase permanent magnet brushless machine (DTPPMBLM) is the key subsystem in EPAS. The strong mutual coupling and nonlinearity of DTPPMBLM as well as its drive make it very difficult to obtain a comprehensive mathematical model. This paper proposes a new method to modelling the DTPPMBLM and drive based on the matrix and tensor approach (MTA). The magnetic equivalent circuit (MEC) is used to model the magnetic field of DTPPMBLM. The switching mode of the converter is analysed and modelled theoretically, based on which the DTPPMBLM and drive is coupled with MTA. Then, the MTA and two dimensional finite element analysis (2D‐FEA) model are used to simulate the various steady‐state and transient performances of the 2 × 1.8 kW DTPPMBLM. Comparison of the simulation results verifies the feasibility of MTA. The results suggest that MTA may be an efficient approach for the DTPPMBLM and drive. The experimental results are reported to show that the modelling scheme has good estimation performance under different operation conditions of the DTPPMBLM.
Adaptive sliding mode technique‐based electromagnetic suspension system with linear switched reluctance actuator
Authors: Lin Jiongkang , Cheng Ka Wai Eric , Zhang Zhu , Cheung Norbert C. , Xue Xiangdang
Published: December 2014

Linear switched reluctance actuator (LSRA) is of great potential using in kind of high‐force linear applications such as automotive suspension system. In this study, an electrical controlled active suspension system is built. Bi‐directional power amplifier is used to supply power to and absorb generated energy from linear actuator based on the movement requirement. The linear motions are accomplished by retracting and extending the LSRA. With regard to the established electromagnetic suspension system, a real‐time control algorithm is developed. Sliding model technique with adaptive mechanism is studied to compensate the system non‐linearities and external road profile. Experiments are conducted at the laboratory to present the high performance of proposed active suspension system.
Trajectory sensitivity analysis on the equivalent one‐machine‐infinite‐bus of multi‐machine systems for preventive transient stability control
Authors: Xu Yan , Dong Zhao Yang , Zhao Junhua , Xue Yusheng , Hill David John
Published: December 2014

A new approach for power system transient stability preventive control is proposed by performing trajectory sensitivity analysis on the one‐machine‐infinite‐bus (OMIB) equivalence of multi‐machine systems. Exact instability time/angle are determined from the equivalent OMIB power–angle curve; the trajectory sensitivity is calculated at the instability time and the transient stability of the multi‐machine system is controlled by constraining the OMIB's angle excursion at the instability time to that of the critical OMIB which corresponds to the marginally stable condition of the system. The required preventive control action (generation rescheduling) can be efficiently solved via a linear programming model with the OMIB trajectory sensitivities‐based constraints. Simulation results on the New England 10‐machine 39‐bus system and a 285‐machine and 1648‐bus system validate its effectiveness and superiority over previous trajectory sensitivity applications to this problem.
Constitutive parameters extraction for thin two‐dimensional cylinders based on scattering field measurements
Authors: Vulfin Vladimir , Shavit Reuven
Published: December 2014

This study presents an analytical method for extracting the constitutive parameters of an isotropic two‐dimensional magneto‐dielectric thin cylinder (small radius compared with the wavelength). The method is based on the scattered far field information to a plane wave illumination. Three variations of the method are presented. First, the complex monostatic scattered fields of two orthogonal polarisations are used to extract the complex constitutive parameters (permittivity and permeability) of a lossy cylinder. Second, the complex bistatic and monostatic scattered fields for a single polarisation are used to extract the complex permittivity and permeability. Third, the absolute value of the monostatic radar cross section for two orthogonal polarisations is used to extract the complex permittivity or permeability. An approximation for a small argument is used to obtain a simple polynomial expression for the scattered field to extract the constitutive parameters. Numerical examples to validate the proposed extraction methods are shown and the results are satisfactory.
Radiolocation and tracking of automatic identification system signals for maritime situational awareness
Authors: Papi Francesco , Tarchi Dario , Vespe Michele , Oliveri Franco , Borghese Francesco , Aulicino Giuseppe , Vollero Antonio
Published: December 2014

The automatic identification system (AIS), a ship reporting system originally designed for collision avoidance, is becoming a cornerstone of maritime situational awareness. The recent increase of terrestrial networks and satellite constellations of receivers is providing global tracking data that enable a wide spectrum of applications beyond collision avoidance. Nevertheless, AIS suffers the lack of security measures that makes it prone to receiving positions that are unintentionally incorrect, jammed or deliberately falsified. In this study, the authors’ analyse a solution to the problem of AIS data verification that can be implemented within a generic networks of ground AIS base stations with no need for additional sensors or technologies. The proposed approach combines a classic radio‐localisation method based on time difference of arrival with an extended Kalman filter designed to track vessels in geodetic coordinates. The approach is validated using anonymised real AIS data collected by multiple base stations that partly share coverage areas. The results show a deviation between the estimated origin of detected signals and the broadcast position data in the order of hundreds of metres, therefore demonstrating the operational potential of the methodology.
Multi‐level stable and energy‐efficient clustering protocol in heterogeneous wireless sensor networks
Authors: Farouk Fifi , Rizk Rawya , Zaki Fayez W.
Published: December 2014

Classical clustering protocols in wireless sensor networks (WSNs) assume that all nodes are equipped with the same amount of energy. As a result, they cannot take full advantage of the presence of node heterogeneity. In this study, a stable and energy‐efficient clustering (SEEC) protocol for heterogeneous WSNs is proposed. In addition, the extension to multi‐level of SEEC is presented. It depends on the network structure that is divided into clusters. Each cluster has a powerful advanced node and some normal nodes deployed randomly in this cluster. In the multi‐level architectures, more powerful supper nodes are assigned to cover distant sensing areas. Each type of nodes has its role in the sensing, aggregation or transmission to the base station. At each level of heterogeneity, the optimum number of powerful nodes that achieves the minimum energy consumption of the network is obtained. The proposed protocol is a heterogeneous awareness to prolong the stability period, which is crucial for many applications. The performance of the proposed protocol is compared by existing homogeneous and heterogeneous protocols. Simulation results show that the proposed protocol provides a longer stability period, more energy efficiency and higher average throughput than the existing protocols.
Identification of voltage stability condition of a power system using measurements of bus variables
Authors: Hazarika Durlav , Talukdar Bani Kanta , Gupta Brajesh Mohan
Published: December 2014

Several online methods were proposed for investigating the voltage stability condition of an interconnected power system using the measurements of voltage and current phasors at a bus. For this purpose, phasor measurement units (PMUs) are used. A PMU is a device which measures the electrical waves on an electrical network, using a common time source (reference bus) for synchronisation. This study proposes a method for online monitoring of voltage stability condition of a power system using measurements of bus variables namely – (i) real power, (ii) reactive power and (iii) bus voltage magnitude at a bus. The measurements of real power, reactive power and bus voltage magnitude could be extracted/captured from a smart energy meter. The financial involvement for implementation of the proposed method would significantly lower compared with the PMU‐based method.
Migration of finite sized particles in a laminar square channel flow from low to high Reynolds numbers
Authors: Abbas M. , Magaud P. , Gao Y. , Geoffroy S.
Published: December 2014

The migration of neutrally buoyant finite sized particles in a Newtonian square channel flow is investigated in the limit of very low solid volumetric concentration, within a wide range of channel Reynolds numbers Re = [0.07-120]. In situ microscope measurements of particle distributions, taken far from the channel inlet (at a distance several thousand times the channel height), revealed that particles are preferentially located near the channel walls at Re > 10 and near the channel center at Re < 1. Whereas the cross-streamline particle motion is governed by inertia-induced lift forces at high inertia, it seems to be controlled by shear-induced particle interactions at low (but finite) Reynolds numbers, despite the low solid volume fraction (<1%). The transition between both regimes is observed in the range Re = [1-10]. In order to exclude the effect of multi-body interactions, the trajectories of single freely moving particles are calculated thanks to numerical simulations based on the force coupling method. With the deployed numerical tool, the complete particle trajectories are accessible within a reasonable computational time only in the inertial regime (Re > 10). In this regime, we show that (i) the particle undergoes cross-streamline migration followed by a cross-lateral migration (parallel to the wall) in agreement with previous observations, and (ii) the stable equilibrium positions are located at the midline of the channel faces while the diagonal equilibrium positions are unstable. At low flow inertia, the first instants of the numerical simulations (carried at Re = O(1)) reveal that the cross-streamline migration of a single particle is oriented towards the channel wall, suggesting that the particle preferential positions around the channel center, observed in the experiments, are rather due to multi-body interactions.
A family of steady two-phase generalized Forchheimer flows and their linear stability analysis
Authors: Hoang Luan T. , Ibragimov Akif , Kieu Thinh T.
Published: December 2014

We model multi-dimensional two-phase flows of incompressible fluids in porous media using generalized Forchheimer equations and the capillary pressure. First, we find a family of steady state solutions whose saturation and pressure are radially symmetric, and velocities are rotation-invariant. Their properties are investigated based on relations between the capillary pressure, each phase’s relative permeability and Forchheimer polynomial. Second, we analyze the linear stability of those steady states. The linearized system is derived and reduced to a parabolic equation for the saturation. This equation has a special structure depending on the steady states which we exploit to prove two new forms of the lemma of growth of Landis-type in both bounded and unbounded domains. Using these lemmas, qualitative properties of the solution of the linearized equation are studied in details. In bounded domains, we show that the solution decays exponentially in time. In unbounded domains, in addition to their stability, the solution decays to zero as the spatial variables tend to infinity. The Bernstein technique is also used in estimating the velocities. All results have a clear physical interpretation.
Multirate delivery of multiple therapeutic agents from metal-organic frameworks
Authors: McKinlay Alistair C. , Allan Phoebe K. , Renouf Catherine L. , Duncan Morven J. , Wheatley Paul S. , Warrender Stewart J. , Dawson Daniel , Ashbrook Sharon E. , Gil Barbara , Marszalek Bartosz , Düren Tina , Williams Jennifer J. , Charrier Cedric , Mercer Derry K. , Teat Simon J. , Morris Russell E.
Published: December 2014

The highly porous nature of metal-organic frameworks (MOFs) offers great potential for the delivery of therapeutic agents. Here, we show that highly porous metal-organic frameworks can be used to deliver multiple therapeutic agents—a biologically active gas, an antibiotic drug molecule, and an active metal ion—simultaneously but at different rates. The possibilities offered by delivery of multiple agents with different mechanisms of action and, in particular, variable timescales may allow new therapy approaches. Here, we show that the loaded MOFs are highly active against various strains of bacteria.