bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and study of superabsorbent properties of acryloylated starch ester grafted with acrylic acid
Authors: Mohammed Aliyu D. , Young Desmond A. , Vosloo Hermanus C. M.
Published: October 2014

A superabsorbent polymer has been prepared by acryloylation of starch followed by grafting with acrylic acid (AA) using Fenton's initiation system (Fe2+/H2O2). Fourier‐transform infrared spectroscopy (FTIR) analyses provided evidence for starch ester formation and grafting of AA onto its backbone. Further characterization of the product was carried out using XRD, SEM and thermogravimetric (TGA) techniques. The product, which has a low yield of homopolymer and exhibits more adhesive and film forming properties than the direct method of grafting AA onto starch, was used for water absorption analysis. The neutralized product showed a remarkable water absorption capacity (127 g/g) much higher than the polymer synthezised from direct grafting.
Physicochemical properties of lipase‐catalyzed laurylation of corn starch
Authors: Gao Yan , Wang Lan , Yue Xiali , Xiong Guangquan , Wu Wenjin , Qiao Yu , Liao Li
Published: October 2014

Corn starch was esterified with lauric acid by using lipase as catalyst in low moisture. The physicochemical and granular properties of esterified starches were determined, including transmittance, syneresis, swelling power, solubility, and thermal analysis, as well as SEM and XRD analysis. The amylose content of esterified starches was in the range of 47.31–48.69%, corresponding with the degree of substitution (DS) ranging from 0.0033 to 0.0151. There was a significant increase in syneresis, swelling power, solubility, and gelatinization temperature, but a decrease in transmittance of esterified starches. The results of SEM and XRD analysis revealed that esterification led to apophyses and pores on the surface of starch granules, but caused few changes in the crystalline structure of esterified starch (DS = 0.0109, 0.0151). Thermal gravimetric analysis (TG) indicated that the esterified starch showed thermal instability compared with native starch.
Effects of heat moisture treatment with erythritol on the physicochemical properties of wheat starch
Authors: Sun Qingjie , Dai Lei , Nan Chong , Ji Na , Xiong Liu
Published: October 2014

Wheat starch was impregnated with erythritol and subjected to heat moisture treatment (HMT) (100°C, 20% moisture, 12 h). The effects of HMT on the pasting, thermal, and morphological properties of the treated wheat starch–erythritol mixture (H‐WSEM) were evaluated. The peak viscosity, trough viscosity, final viscosity, and breakdown of H‐WSEM markedly decreased, whereas pasting temperature increased. Compared with the To, Tp, and Tc of the untreated wheat starch–erythritol mixture (WSEM), those of H‐WSEM considerably increased; unlike the ΔH of WSEM, that of H‐WSEM decreased. SEM showed that numerous erythritol granules appeared on the surface of the starch granules in WSEM, but that the H‐WSEM surface was smooth and irregular. Compared with the holes of the WSEM gel, those of the H‐WSEM gel were smaller and were characterized by a thinner matrix surrounding the pores. The XRD patterns revealed that the amorphous region of H‐WSEM was larger than that of WSEM.
Effect of sugar alcohol on physicochemical properties of wheat starch
Authors: Sun Qingjie , Nan Chong , Dai Lei , Ji Na , Xiong Liu
Published: October 2014

Effects of sugar alcohol (maltitol, erythritol, and xylitol) at different concentration levels (sugar alcohol/starch ratio 0.1:1, 0.2:1, 0.5:1, 1:1, 2:1, w/w, db) on the physicochemical properties of wheat starch were studied. The swelling power decreased significantly with sugar alcohols content increasing at 95°C. Rapid visco‐analyser (RVA) breakdown and setback of wheat starch decreased with increasing sugar alcohol content. Texture measurements showed that hardness of wheat starch gel rose with increasing content of sugar alcohols, indicating that sugar alcohols probably facilitated the retrogradation of amylose following the order of xylitol > maltitol > erythritol at a sugar alcohol/starch ratio of 2:1. The gelatinization temperature and enthalpy of wheat starch increased significantly at higher maltitol, erythritol, and xylitol concentrations (≥1:1). Such effects might be contributed to more hydrogen bonds formed between sugar alcohols hydroxyl groups and starch chains and the granule needed greater energy to break away during gelatinization.
Meta‐analyses of human gut microbes associated with obesity and IBD
Authors: Walters William A. , Xu Zech , Knight Rob
Published: October 2014

Recent studies have linked human gut microbes to obesity and inflammatory bowel disease, but consistent signals have been difficult to identify. Here we test for indicator taxa and general features of the microbiota that are generally consistent across studies of obesity and of IBD, focusing on studies involving high‐throughput sequencing of the 16S rRNA gene (which we could process using a common computational pipeline). We find that IBD has a consistent signature across studies and allows high classification accuracy of IBD from non‐IBD subjects, but that although subjects can be classified as lean or obese within each individual study with statistically significant accuracy, consistent with the ability of the microbiota to experimentally transfer this phenotype, signatures of obesity are not consistent between studies even when the data are analyzed with consistent methods. The results suggest that correlations between microbes and clinical conditions with different effect sizes (e.g. the large effect size of IBD versus the small effect size of obesity) may require different cohort selection and analysis strategies.
Prenatal expression of thioredoxin reductase 1 (TRXR1) and microsomal glutathione transferase 1 (MGST1) in humans
Authors: Björkhem-Bergman Linda , Johansson Maria , Morgenstern Ralf , Rane Anders , Ekström Lena
Published: October 2014

In conclusion, the expression of TXNRD1 is higher in fetuses than in adults and might be of importance during fetal life. Hepatic TXNRD1 and MGST1 are co‐expressed in both fetuses and adults suggesting common regulatory mechanisms.
Cell surface N‐glycans influence the level of functional E‐cadherin at the cell–cell border
Authors: Hall M. Kristen , Weidner Douglas A. , Dayal Sahil , Schwalbe Ruth A.
Published: October 2014

E‐cadherin is crucial for adhesion of cells to each other and thereby development and maintenance of tissue. While it is has been established that N‐glycans inside the cell impact the level of E‐cadherin at the cell surface of epithelial‐derived cells, it is unclear whether N‐glycans outside the cell control the clustering of E‐cadherin at the cell–cell border. Here, we demonstrate reduction of N‐glycans at the cell surface weakened the recruitment and retention of E‐cadherin at the cell–cell border, and consequently reduced the strength of cell–cell interactions. We conclude that N‐glycans at the cell surface are tightly linked to the placement of E‐cadherin at the cell–cell border and thereby control E‐cadherin mediated cell–cell adhesion.
Application of Next-Generation Sequencing Technology in Forensic Science
Authors: Yang Yaran , Xie Bingbing , Yan Jiangwei
Published: October 2014

Next-generation sequencing (NGS) technology, with its high-throughput capacity and low cost, has developed rapidly in recent years and become an important analytical tool for many genomics researchers. New opportunities in the research domain of the forensic studies emerge by harnessing the power of NGS technology, which can be applied to simultaneously analyzing multiple loci of forensic interest in different genetic contexts, such as autosomes, mitochondrial and sex chromosomes. Furthermore, NGS technology can also have potential applications in many other aspects of research. These include DNA database construction, ancestry and phenotypic inference, monozygotic twin studies, body fluid and species identification, and forensic animal, plant and microbiological analyses. Here we review the application of NGS technology in the field of forensic science with the aim of providing a reference for future forensics studies and practice.
THE QUASI-ENTRENCHMENT OF CONSTITUTIONAL STATUTES
Authors: Ahmed Farrah , Perry Adam
Published: October 2014

The British constitution is famously unentrenched: constitutional laws are not intrinsically more difficult to override than ordinary laws. However, in the largely overlooked 2012 case ofH v Lord Advocate, the Supreme Court said that the Scotland Act 1998 cannot be impliedly repealed due to its “fundamental constitutional” status. Unless judicial thinking changes, courts in the future may treat constitutional statutes, like the Scotland Act, as capable only of express repeal, making such statutes “quasi-entrenched”. In this article, we argue that, as a judicial innovation, the quasi-entrenchment of constitutional statutes lacks a sound legal basis. Parliament can make its intention to repeal a constitutional statute clear without making it express, and judges cannot, on their own initiative, ignore Parliament's clear decision to repeal even a constitutional statute.
Adcumulate mafic dykes in layered intrusions: a case study of a late-stage dyke in the Bayantsagaan layered intrusion, Mongolia
Authors: CHISTYAKOVA SOFYA , LATYPOV RAIS
Published: October 2014

We have discovered an adcumulate late-stage dyke in the Bayantsagaan layered intrusion. The 11-cm-thick dyke is composed of fresh troctolite with no signs of chilling against the host leucotroctolite. Texturally, both the dyke and its host are medium-grained plagioclase-olivine-magnetite cumulates. The dyke is however finer grained and contains less interstitial material. Two geochemical features characterize the dyke: it is compositionally more evolved than the host, as indicated by its lower real and normative An-content in plagioclase, whole-rock Cr and Mg-number; and it is highly depleted in all incompatible components (e.g. K2O, Y and rare earth elements or REEs) that have much lower concentrations than in the host. The depletion in REEs is extreme and has not been reported earlier for any troctolitic rocks. It has an internal reverse zonation with an inwards increase in compatible MgO and TiO2 and a decrease in all incompatible elements, suggesting an inwards decrease in the amount of trapped melt. We interpret this late-stage dyke as having formed from a residual melt that was channelled along a fissure in solidifying cumulates. The flow of the melt resulted in the very efficient removal of a boundary layer of evolved liquid from crystals growing on the walls of the dyke. This resulted in an almost perfect adcumulate that is extremely depleted in incompatible components.
MODELING NONSTATIONARY AND LEPTOKURTIC FINANCIAL TIME SERIES
Authors: Chen Ying , Spokoiny Vladimir
Published: October 2014

Financial time series is often assumed to be stationary and has a normal distribution in the literature. Both assumptions are however unrealistic. This paper proposes a new methodology with a focus on volatility estimation that is able to account for nonstationarity and heavy tails simultaneously. In particular, a local exponential smoothing (LES) approach is developed, in which weak estimates with different memory parameters are aggregated in a locally adaptive way. The procedure is fully automatic and the parameters are tuned by a new propagation approach. The extensive and practically oriented numerical results confirm the desired properties of the constructed estimate: it performs stable in a nearly time homogeneous situation and is sensitive to structural shifts. Our main theoretical “oracle” result claims that the aggregated estimate performs as good as the best estimate in the considered family. The results are stated under realistic and unrestrictive assumptions on the model.
Variability in the effects of bilingualism on cognition: It is not just about cognition, it is also about bilingualism
Authors: KAUSHANSKAYA MARGARITA , PRIOR ANAT
Published: October 2014

Valian (2014) suggests that the messy state of the literature examining the effects of bilingualism on executive functioning (EF) stems from lack of clarity in how EFs are defined and measured, and from lack of control over other factors that can modulate EF. We argue that the lack of clarity in how bilingualism is defined and measured is no less problematic. We focus our commentary on two related issues.
Doubling down on multifactorial approaches to the study of bilingualism & executive control
Authors: TITONE DEBRA , PIVNEVA IRINA , SHEIKH NAVEED A. , WEBB NICOLE , WHITFORD VERONICA M.
Published: October 2014

The study of bilingualism has generated great interest about a core issue: does the experience of using two or more languages lead to enduring changes in the bilingual brain. This issue is often framed as a search for bilingual advantages in cognition, most notably behavioral performance on executive control tasks. Valian's timely keynote (2014) adopts this framing.
SOBOLEV SPACES ON LOCALLY COMPACT ABELIAN GROUPS AND THE BOSONIC STRING EQUATION
Authors: GÓRKA PRZEMYSŁAW , REYES ENRIQUE G.
Published: October 2014

Motivated by a class of nonlinear nonlocal equations of interest for string theory, we introduce Sobolev spaces on arbitrary locally compact abelian groups and we examine some of their properties. Specifically, we focus on analogs of the Sobolev embedding and Rellich–Kondrachov compactness theorems. As an application, we prove the existence of continuous solutions to a generalized bosonic string equation posed on an arbitrary compact abelian group, and we also remark that our approach allows us to solve very general linear equations in a$p$-adic context.
LOGARITHMIC CONVEXITY OF AREA INTEGRAL MEANS FOR ANALYTIC FUNCTIONS II
Authors: WANG CHUNJIE , XIAO JIE , ZHU KEHE
Published: October 2014

For$0<p<\infty$and$-2\leq {\it\alpha}\leq 0$we show that the$L^{p}$integral mean on$r\mathbb{D}$of an analytic function in the unit disk$\mathbb{D}$with respect to the weighted area measure$(1-|z|^{2})^{{\it\alpha}}\,dA(z)$is a logarithmically convex function of$r$on$(0,1)$.
Changing precipitation pattern alters soil microbial community response to wet-up under a Mediterranean-type climate
Authors: Barnard Romain L , Osborne Catherine A , Firestone Mary K
Published: October 2014

A large soil CO2 pulse is associated with rewetting soils after the dry summer period under a Mediterranean-type climate, significantly contributing to grasslands’ annual carbon budget. Rapid reactivation of soil heterotrophs and a pulse of available carbon are both required to fuel the CO2 pulse. Understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting changes in carbon cycling. Here, we investigated the effects of extending winter rainfall into the normally dry summer period on soil microbial response to a controlled rewetting event, by following the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in intact soil cores (from a California annual grassland) previously subjected to three different precipitation patterns over 4 months (full summer dry season, extended wet season and absent dry season). Phylogenetic marker genes for bacteria and fungi were sequenced before and after rewetting, and the abundance of these genes and transcripts was measured. After having experienced markedly different antecedent water conditions, the potentially active bacterial communities showed a consistent wet-up response. We found a significant positive relation between the extent of change in the structure of the potentially active bacterial community and the magnitude of the CO2 pulse upon rewetting dry soils. We suggest that the duration of severe dry summer conditions characteristic of the Mediterranean climate is important in conditioning the response potential of the soil microbial community to wet-up as well as in framing the magnitude of the associated CO2 pulse.
Optimization and validation of a multiresidue method for pesticide determination in maize using gas chromatography coupled to tandem mass spectrometry
Authors: Facco J. F. , Martins M. L. , Bernardi G. , Prestes O. D. , Adaime M. B. , Zanella R.
Published: October 2014

A modified QuEChERS method was optimized for pesticide multiresidue extraction from maize for further GC-MS/MS determination.
Limonene: a versatile chemical of the bioeconomy
Authors: Ciriminna Rosaria , Lomeli-Rodriguez Monica , Demma Carà Piera , Lopez-Sanchez Jose A. , Pagliaro Mario
Published: October 2014

Largely increased use of (+)-limonene in the emerging bioeconomy will be twofold: in advanced formulations and as raw material to manufacture valued fine chemicals and high-performance polymers, especially using CO2 as co-monomer.
Halogen-bonded halide networks from chiral neutral spacers
Authors: Lieffrig Julien , Niassy Arnode G. , Jeannin Olivier , Fourmigué Marc
Published: October 2014

Chiral, ditopic, bis-iodinated molecules can form helical networks due to halogen bonding interactions when co-crystallised with halide tetraalkylammonium salts.
Electron driven reactions in sulphur containing analogues of uracil: the case of 2-thiouracil
Authors: Kopyra J. , Abdoul-Carime H. , Kossoski F. , Varella M. T. do N.
Published: October 2014

Electron induced fragmentation of 2-thiouracil.
Biomimetic super-lyophobic and super-lyophilic materials applied for oil/water separation: a new strategy beyond nature
Authors: Wang Ben , Liang Weixin , Guo Zhiguang , Liu Weimin
Published: October 2014

Investigations in the field of oil/water separation materials with special wettability may accelerate the settlement of industrial oily wastewater and ocean oil spill accidents.
A laboratory study of the performance of the handheld diffusion size classifier (DiSCmini) for various aerosols in the 15–400 nm range
Authors: Bau S. , Zimmermann B. , Payet R. , Witschger O.
Published: October 2014

Comparison of DiSCmini data to reference data for polydisperse test aerosols in terms of diameter, number concentration and alv-LDSA.
Ashitaba (Angelica keiskei) extract prevents adiposity in high-fat diet-fed C57BL/6 mice
Authors: Zhang Tianshun , Yamashita Yoko , Yasuda Michiko , Yamamoto Norio , Ashida Hitoshi
Published: October 2014

Two main chalcones, 4-hydroxyderricin and xanthoangelol, from Ashitaba, which is a food ingredient and a folk medicine in Asia, have been demonstrated to modulate lipid metabolism in 3T3-L1 and HepG2 cells.
Enhancing vitamin E bioaccessibility: factors impacting solubilization and hydrolysis of α-tocopherol acetate encapsulated in emulsion-based delivery systems
Authors: Yang Ying , Decker Eric Andrew , Xiao Hang , McClements David Julian
Published: October 2014

Impact of free fatty acid chain length on vitamin E bioaccessibility: long chain FFAs form mixed micelles that easily accommodate vitamin E, whereas medium chain FFAs do not.
Controllable fabrication of multifunctional 1D Ag-based coordination polymer@PVP nanowires
Authors: Lv Bo , Shi Xiaobo , Ma Xiaoyan , Zhang Zhiyang , Wang Kuaibing
Published: October 2014

The composite Ag-based coordination polymer@PVP nanowires have been mildly synthesized in the presence of PVP, which may be potentially applied in anticancer and antibacterial fields.
Synthesis, characterization, and physical properties of a poly(acrylamide-co-4-cyanobiphenyl-4′-oxyundecylacrylate)
Authors: Kamal Tahseen , Park Soo-young
Published: October 2014

The synthesis and characterization of a copolymer containing an LC unit and a hydrophilic unit are reported. The copolymer forms hydrogel in water with the LC component serving as the physical crosslink.
Synthesis of PS/PO-chimeric oligonucleotides using mixed oxathiaphospholane and phosphoramidite chemistry
Authors: Radzikowska Ewa , Baraniak Janina
Published: October 2014

Chimeric oligonucleotides containing stereoregular phosphorothioate and natural phosphodiester linkages have been obtained on the solid phase support using nucleoside oxathiaphospholanes and commercially available nucleoside phosphoramidites.
Construction of dispirocyclohexanes via amine-catalyzed [2 + 2 + 2] annulations of Morita–Baylis–Hillman acetates with exocyclic alkenes
Authors: Chen Rongshun , Xu Silong , Fan Xia , Li Hanyuan , Tang Yuhai , He Zhengjie
Published: October 2014

Divergent amine-catalyzed [2 + 2 + 2] annulations of Morita–Baylis–Hillman acetates with exocyclic alkenes were developed for the convergent construction of multistereogenic dispirocyclohexanes.
A DFT study on structure, stabilities and electronic properties of double magnesium doped gold clusters
Authors: Bhattacharjee Debajyoti , Mishra Bhupesh Kr. , Deka Ramesh Ch.
Published: October 2014

The doping of two Mg atoms on Au-clusters has considerable effects on the structure and stability of gold clusters. The doped clusters enhance the stability of pure Au-clusters as observed from the binding energy plot.
Antioxidant and hepatoprotective effects of an organic grapevine leaf (Vitis labrusca L.) extract in diabetic rats
Authors: Lacerda Denise dos Santos , Santos Carolina Ferreira , Oliveira Alice Spiecker , Zimmermann Rafaela , Schneider Ricardo , Agostini Fabiana , Dani Caroline , Funchal Cláudia , Gomez Rosane
Published: October 2014

Changes on metabolic, biochemical and oxidative parameters in the livers of diabetic rats after chronic administration of an aqueous extract of organic grapevine leaves.
Vesicular self-assembly of a natural triterpenoid arjunolic acid in aqueous medium: study of entrapment properties and in situ generation of gel–gold nanoparticle hybrid material
Authors: Bag Braja Gopal , Majumdar Rakhi
Published: October 2014

Formation of vesicular gel and gel–gold nanoparticle hybrid material from arjunolic acid extractable from the saw-dust of Terminalia arjuna.
Diazo group as a new chemical reporter for bioorthogonal labelling of biomolecules
Authors: Josa-Culleré Laia , Wainman Yelena A. , Brindle Kevin M. , Leeper Finian J.
Published: October 2014

Diazoacetyl groups undergo spontaneous cycloaddition with strained alkenes and alkynes and can be bioorthogonal reporter groups labelling proteins and glycans.
Laser-assisted calcium phosphate deposition on polymer substrates in supersaturated solutions
Authors: Oyane Ayako , Sakamaki Ikuko , Pyatenko Alexander , Nakamura Maki , Ishikawa Yoshie , Shimizu Yoshiki , Kawaguchi Kenji , Koshizaki Naoto
Published: October 2014

Calcium phosphate (CaP) deposition was induced on optically semitransparent polymers irradiated with laser in a supersaturated CaP solution, but not on a transparent polymer.
Experimental optimization of a passive planar rhombic micromixer with obstacles for effective mixing in a short channel length
Authors: Bernacka-Wojcik Iwona , Ribeiro Susana , Wojcik Pawel Jerzy , Alves Pedro Urbano , Busani Tito , Fortunato Elvira , Baptista Pedro Viana , Covas José António , Águas Hugo , Hilliou Loic , Martins Rodrigo
Published: October 2014

A short passive planar micromixer was experimentally optimised using statistical methods to determine parameter significance and most desirable geometry.
Anti-inflammatory and hypoglycemic efficacy of Poria cocos and Dioscorea opposita in prediabetes mellitus rats
Authors: Lee Hsiu-Chuan , Cheng Wen-Yi , Huang Brian E. T.-G. , Hsu Yi-Hao , Huang Shih-Yi
Published: October 2014

Poria cocos(Fu Ling) andDioscorea opposita(Chinese Yam) were suggested to have potential benefits in blood sugar control.
Simple and green synthesis of nitrogen-, sulfur-, and phosphorus-co-doped carbon dots with tunable luminescence properties and sensing application
Authors: Wang Chunfeng , Sun Dong , Zhuo Kelei , Zhang Hucheng , Wang Jianji
Published: October 2014

N/S/P-co-doped carbon dots with tunable luminescence properties were synthesized from cucumber juice, and used as fluorescent probes for Hg2+ detection.
Formation of dications bearing a S(OH)2+ group from long-lived 9,9-dimethyl-10 R-phenanthrenium cations in FSO3H–SbF5/SO2ClF/SO2: a mechanistic study
Authors: Salnikov George E. , Genaev Alexander M. , Bushmelev Vladimir A. , Nefedov Andrey A. , Shubin Vyacheslav G.
Published: October 2014

A key step in the reaction mechanism is addition of SO2 to the superelectrophilic intermediates – protonated phenanthrenium cations.
Ultrastable iridium–ceria nanopowders synthesized in one step by solution combustion for catalytic hydrogen production
Authors: Nguyen Thanh-Son , Postole Georgeta , Loridant Stéphane , Bosselet Françoise , Burel Laurence , Aouine Mimoun , Massin Laurence , Gélin Patrick , Morfin Franck , Piccolo Laurent
Published: October 2014

Solution combustion generates mesoporous ceria with strongly anchored Ir nanoparticles, which are efficient methane reforming catalysts.
Facile preparation of mesoporous graphenes by the sacrificial template approach for direct methanol fuel cell application
Authors: Cao Jianyu , Zhuang Hui , Guo Mengwei , Wang Hongning , Xu Juan , Chen Zhidong
Published: October 2014

Mesoporous graphenes were synthesized via a template-assisted pyrolysis approach and used as a material for a porous diffusion layer in direct methanol fuel cells.
Apo, Zn2+-bound and Mn2+-bound structures reveal ligand-binding properties of SitA from the pathogen Staphylococcus pseudintermedius
Authors: Abate Francesca , Malito Enrico , Cozzi Roberta , Lo Surdo Paola , Maione Domenico , Bottomley Matthew J.
Published: October 2014

The Gram-positive bacterium Staphylococcus pseudintermedius is a leading cause of canine bacterial pyoderma, resulting in worldwide morbidity in dogs. S. pseudintermedius also causes life-threatening human infections. Furthermore, methicillin-resistant S. pseudintermedius is emerging, resembling the human health threat of methicillin-resistant Staphylococcus aureus. Therefore it is increasingly important to characterize targets for intervention strategies to counteract S. pseudintermedius infections. Here we used biophysical methods, mutagenesis, and X-ray crystallography, to define the ligand-binding properties and structure of SitA, an S. pseudintermedius surface lipoprotein. SitA was strongly and specifically stabilized by Mn2+ and Zn2+ ions. Crystal structures of SitA complexed with Mn2+ and Zn2+ revealed a canonical class III solute-binding protein with the metal cation bound in a cavity between N- and C-terminal lobes. Unexpectedly, one crystal contained both apo- and holo-forms of SitA, revealing a large side-chain reorientation of His64, and associated structural differences accompanying ligand binding. Such conformational changes may regulate fruitful engagement of the cognate ABC (ATP-binding cassette) transporter system (SitBC) required for metal uptake. These results provide the first detailed characterization and mechanistic insights for a potential therapeutic target of the major canine pathogen S. pseudintermedius, and also shed light on homologous structures in related staphylococcal pathogens afflicting humans.
Ultra‐low‐cost colour demosaicking VLSI design for real‐time video applications
Authors: Chen Shih‐Lun , Chang Huan‐Rui , Lin Ting‐Lan
Published: October 2014

A novel low‐complexity and high‐quality colour demosaicking algorithm is proposed for very large‐scale integration (VLSI) implementation for real‐time video applications. It consists of a boundary detector, a boundary mirror model and five green and red–blue colour interpolation models. Two of the five interpolation models can be selected adaptively according to boundary and position information. In addition, a boundary mirror machine and identical direction technique were used to improve the qualities of the reconstructed images. To reduce the hardware cost, memory requirement and power consumption, a hardware‐sharing technique and register bank design were used to realise the proposed algorithm. The VLSI architecture of this work contains only 2.9 K gate counts and its core area is 35 966 μm2 synthesised by a 0.18 μm CMOS process. The synthesised results show that this design performs an operating frequency of 100 MHz processing rate by consuming only 1.83 mW. Compared with the previous low‐complexity designs, this work not only reduces at least 48.2% of gate counts and 96.7% of power consumption but also improves the average CPSNR quality by more than 0.78 dB.
Digitally controlled oscillator using active inductor based on CMOS inverters
Authors: Ghorbel I. , Haddad F. , Barthélemy H. , Rahajandraibe W. , Loulou M. , Mnif H.
Published: October 2014

A digitally controlled oscillator (DCO) suitable for multi‐standards radio‐frequency (RF) operation is presented. It has an LC topology using an active inductor based on CMOS controllable inverters. The tunability of the oscillator frequency is ensured by varying the digital word applied to the inverters’ control voltages. The proposed DCO has a small area and exhibits a high‐frequency tuning range while achieving low power consumption with good stability against process variations.
Legendre polynomial based fast minimum variance beamforming method for medical ultrasound systems
Authors: Bae MooHo , Park Sung‐Bae , Kwon Sung‐Jae
Published: October 2014

Recently, minimum variance beamforming (MV BF) has been actively investigated as a method to improve the performance of an ultrasound system beamformer, especially in terms of both the lateral and contrast resolution. However, since the inverse spatial covariance matrix must be calculated, a severe problem with the method is the prohibitive computational complexity. Among numerous attempts to overcome the problem, notable ones are the fast MV BF method based on principal component analysis and beam space adaptive beamforming. The two are similar in transforming an original signal in the element space to the other domain using an orthonormal basis matrix and approximating the covariance matrix with dimensionality reduction in the transformed domain, hence simplifying the inversion of the matrix. A new method that uses the Legendre polynomial as the basis matrix for such transformation is proposed. The efficacy of the proposed method is verified through Field II simulation. Computer simulation results show that the proposed method is better than or almost equal to the above two methods in the approximation error and the lateral response.
Performance metrics of a multirate resource sharing teletraffic model with finite sources under the threshold and bandwidth reservation policies
Authors: Moscholios Ioannis D. , Logothetis Michael D. , Vardakas John S. , Boucouvalas Anthony C.
Published: October 2014

The authors propose a new multirate teletraffic loss model of a single link with certain capacity that accommodates different service‐classes whose calls come from finite traffic sources. Calls compete for the available link bandwidth under the combination of the threshold (TH) and the bandwidth reservation (BR) policies. The TH policy can provide different quality of service among service‐classes by limiting calls of each service‐class up to a certain number, which is a predefined TH, which can be different for each service‐class. The BR policy reserves part of the available link bandwidth to benefit calls of high bandwidth requirements. They show that the proposed model, without the BR policy, has a product form solution (PFS) and prove recursive formulas for the efficient calculation of the call‐level performance metrics, such as time and call congestion probabilities as well as link utilisation. The combination of the TH and BR policies destroys the PFS of the model. However, they show that approximate but recursive formulas still exist for the efficient calculation of the call‐level performance metrics. The accuracy of the proposed formulas is verified through simulation and found to be very satisfactory.
Study of beam transverse properties of a thermionic electron gun for application to a compact THz free electron laser
Authors: Hu Tongning , Pei Yuanji , Qin Bin , Tan Ping , Chen Qushan , Yang Lei , Li Ji
Published: October 2014

A novel thermionic electron gun adopted for use in a high power THz free electron laser (FEL) is proposed in this paper. By optimization of the structural and radiofrequency (RF) parameters, the physical design of the gun is performed using dynamic calculations. Velocity bunching is used to minimize the bunch's energy spread, and the dynamic calculation results indicate that high quality beams can be provided. The transverse properties of the beams generated by the gun are also analyzed. The novel RF focusing effects of the resonance cavity are investigated precisely and are used to establish emittance compensation, which enables the injector length to be reduced. In addition, the causes of the extrema of the beam radius and the normalized transverse emittance are analyzed and interpreted, respectively, and slice simulations are performed to illustrate how the RF focusing varies along the bunch length and to determine the effects of that variation on the emittance compensation. Finally, by observation of the variations of the beam properties in the drift tube behind the electron gun, prospective assembly scenarios for the complete THz-FEL injector are discussed, and a joint-debugging process for the injector is implemented.
Deformability-based red blood cell separation in deterministic lateral displacement devices—A simulation study
Authors: Krüger Timm , Holmes David , Coveney Peter V.
Published: October 2014

We show, via three-dimensional immersed-boundary-finite-element-lattice-Boltzmann simulations, that deformability-based red blood cell (RBC) separation in deterministic lateral displacement (DLD) devices is possible. This is due to the deformability-dependent lateral extension of RBCs and enables us to predict a priori which RBCs will be displaced in a given DLD geometry. Several diseases affect the deformability of human cells. Malaria-infected RBCs, for example, tend to become stiffer than their healthy counterparts. It is therefore desirable to design microfluidic devices which can detect diseases based on the cells' deformability fingerprint, rather than preparing samples using expensive and time-consuming biochemical preparation steps. Our findings should be helpful in the development of new methods for sorting cells and particles by deformability.
Giant persistent photoconductivity in BaTiO3/TiO2 heterostructures
Authors: Plodinec Milivoj , Šantić Ana , Zavašnik Janez , Čeh Miran , Gajović Andreja
Published: October 2014

The persistent photoconductivity (PPC) effect in nanotube arrays of barium titanate and TiO2 (BTO/TiO2NT) was studied at room temperature under daylight illumination. The BTO/TiO2NT heterostructures exhibited a giant PPC effect that was six orders of magnitude higher than the dark conductivity, followed by a slow relaxation for 3 h. The PPC in this material was explained by the existence of defects at the surfaces and the interfaces of the investigated heterostructures. The sample was prepared using a two-step synthesis: the anodization of a Ti-foil and a subsequent hydrothermal synthesis. The structural and electrical characteristics were studied by micro-Raman spectroscopy, field-emission-gun scanning electron microscopy, and impedance spectroscopy.
Surfactant role of Ag atoms in the growth of Si layers on Si(111)√3×√3-Ag substrates
Authors: Yamagami Tsuyoshi , Sone Junki , Nakatsuji Kan , Hirayama Hiroyuki
Published: October 2014

The growth of Si layers on Si(111)√3×√3-Ag substrates was studied for coverages of up to a few mono-layers. Atomically flat islands were observed to nucleate in the growth at 570 K. The top surfaces of the islands were covered in Ag atoms and exhibited a √3×√3 reconstruction with the same surface state dispersions as Si(111)√3×√3-Ag substrates. These results indicate that the Ag atoms on the substrate always hop up to the top of the Si layers.
Photoionization cross section measurements of the excited states of cobalt in the near-threshold region
Authors: Zheng Xianfeng , Zhou Xiaoyu , Cheng Zaiqi , Jia Dandan , Qu Zehua , Yao Guanxin , Zhang Xianyi , Cui Zhifeng
Published: October 2014

We present measurements of photoionization cross-sections of the excited states of cobalt using a two-color, two-step resonance ionization technique in conjunction with a molecular beam time of flight (TOF) mass spectrometer. The atoms were produced by the laser vaporization of a cobalt rod, coupled with a supersonic gas jet. The absolute photoionization cross-sections at threshold and near-threshold regions (0-1.2 eV) were measured, and the measured values ranged from 4.2±0.7 Mb to 10.5±1.8 Mb. The lifetimes of four odd parity energy levels are reported for the first time.
Systematical analysis for the mixed couplings of two adjacent modified split ring resonators and the application to compact microstrip bandpass filters
Authors: Huang Yongjun , Wen Guangjun , Li Jian
Published: October 2014

In this paper we synthesize a new kind of modified split ring resonator (SRR) and characterize its mixed couplings between two adjacent such SRRs with all the possible arrangements on one side of a conventional dielectric substrate. Based on the analysis of the mixed couplings, the compact microstrip bandpass filters composed of the proposed modified SRRs are systematically analyzed. We found that two designs out of all the cases have quite well bandpass filter characteristics, e.g., low insert loss within the wide passband, sharp reductions and transmission zeros out of the passband, and harmonic suppression characteristics for a wide frequency range. Both experimental demonstrations and numerical simulations are performed to verify the designed filters and the results agree well with each other. Such kind of filter design can be flexibly integrated in the miniaturized radio frequency/microwave circuits.
A fractional diffusion equation model for cancer tumor
Authors: Iyiola Olaniyi Samuel , Zaman F. D.
Published: October 2014

In this article, we consider cancer tumor models and investigate the need for fractional order derivative as compared to the classical first order derivative in time. Three different cases of the net killing rate are taken into account including the case where net killing rate of the cancer cells is dependent on the concentration of the cells. At first, we use a relatively new analytical technique called q-Homotopy Analysis Method on the resulting time-fractional partial differential equations to obtain analytical solution in form of convergent series with easily computable components. Our numerical analysis enables us to give some recommendations on the appropriate order (fractional) of derivative in time to be used in modeling cancer tumor.
A Combined Computational–Experimental Study of the Kinetics of Intramolecular Diels–Alder Reactions in a Series of 1,3,8-Nonatrienes
Authors: Lording William J. , Payne Alan D. , Cayzer Tory N. , Sherburn Michael S. , Paddon-Row Michael N.
Published: October 2014

Activation enthalpies for a series of five 1,3,8-nonatriene intramolecular Diels–Alder (IMDA) reactions involving substrates 1–5 have been determined experimentally and Singleton’s natural abundance method has been employed to determine kinetic isotope effects in the IMDA reaction of fumarate 3. The activation enthalpies for the IMDA reactions of the systems possessing a –CH2OCH2– diene/dienophile tether are significantly smaller than their counterparts possessing the –CH2OC(=O)– tether. The experimental activation enthalpies have been used to benchmark computed values from four model chemistries, namely two density functional theory functionals, B3LYP and M06-2X, and two generally very accurate composite ab initio wave function methods, CBS-QB3 and G4(MP2). G4(MP2) outperformed the computationally more expensive CBS-QB3 method, but the vastly cheaper M06-2X/6-31G(d)//B3LYP/6-31G(d) method was sufficiently accurate to be the recommended method of choice for calculating activation parameters. Experimental 2H kinetic isotope effects for the IMDA reaction of fumarate 3 confirmed the computational predictions that this Diels–Alder reaction is concerted but asynchronous.
Modelling and mapping dynamic variability in large fire probability in the lower Sonoran Desert of south-western Arizona
Authors: Gray Miranda E. , Dickson Brett G. , Zachmann Luke J.
Published: October 2014

In the lower Sonoran Desert of south-western Arizona, climate change and non-native plant invasions have the potential to increase the frequency and size of uncommon wildfires. An understanding of where and why ignitions are more likely to become large fires will help mitigate the negative consequences of fire to native ecosystems. We use a generalised linear mixed model and fire occurrence data from 1989 to 2010 to estimate the relative contributions of fuel and other landscape variables to large fire probability, given an ignition. For the 22-year period we examined, a high value for the maximum annual Normalised Difference Vegetation Index was among the strongest predictors of large fire probability, as were low values of road density and elevation. Large fire probability varied markedly between years of moderate and high fine fuel accumulation. Our estimates can be applied to future periods with highly heterogeneous precipitation. Our map-based results can be used by managers to monitor variability in large fire probability, and to implement adaptive fire mitigation at a landscape scale. The approaches we present have global applications to other desert regions that face similar threats from changing climate, altered fuels and potential punctuated changes in fire regimes.
Opponent melanopsin and S-cone signals in the human pupillary light response
Authors: Spitschan Manuel , Jain Sandeep , Brainard David H. , Aguirre Geoffrey K.
Published: October 2014

Significance

Our eyes sense bright light using cones (L, M, and S) and recently discovered melanopsin-containing ganglion cells. Both S cones and melanopsin respond to blueish (short-wavelength) light. How does melanopsin interact with the cones in visual function? We measured the response of the human pupil to isolated stimulation of the different photoreceptors. Our work reveals a curious, opponent response to blue light in the otherwise familiar pupillary light response. Increased stimulation of S cones can cause the pupil to dilate, but this effect is usually masked by a stronger and opposite response from melanopsin-containing cells. Our results have clinical importance because the sensing of blue light is known to be related to seasonal depression, sleep, and pain from bright light.
Capsid expansion mechanism of bacteriophage T7 revealed by multistate atomic models derived from cryo-EM reconstructions
Authors: Guo Fei , Liu Zheng , Fang Ping-An , Zhang Qinfen , Wright Elena T. , Wu Weimin , Zhang Ci , Vago Frank , Ren Yue , Jakana Joanita , Chiu Wah , Serwer Philip , Jiang Wen
Published: October 2014

Significance

T7 phage has been used as a model system to study dsDNA virus capsid assembly and maturation. Yet, atomic capsid models and details of capsid transformations are not elucidated. From our cryo-EM study we have derived near-atomic resolution
reconstructions
of the DNA-free procapsid, a DNA packaging intermediate, and the DNA-packaged, mature phage capsid. From these structures, we have derived the first near-atomic-level model of T7 capsid maturation. The structural knowledge obtained from this study can serve as a platform for analysis of other dsDNA viruses as well as a platform for the development of molecular tools such as improved phage display systems.
RUNX1 is essential for mesenchymal stem cell proliferation and myofibroblast differentiation
Authors: Kim Woosook , Barron David A. , San Martin Rebeca , Chan Keith S. , Tran Linda L. , Yang Feng , Ressler Steven J. , Rowley David R.
Published: October 2014

Significance

Recruitment, proliferation, and differentiation of myofibroblasts are common in many disease states. Mechanisms that regulate proliferation and differentiation are poorly understood, although TGF-β is a key inducer of differentiation. Here, we report, for the first time to our knowledge, that runt-related transcription factor 1 (RUNX1) regulates mesenchymal stem cell (MSC) biology and progenitor cell commitment to myofibroblasts. In this work, we describe the first identification, to our knowledge, of tissue-resident MSCs from adult normal human prostate gland and the role of these MSCs as myofibroblast precursors. We also pinpoint the role of RUNX1 in regulating proliferation and differentiation in both marrow-derived and tissue-resident MSCs. Perturbation of RUNX1 activity may provide insights for developing antifibrotic and anticancer therapies via targeting the reactive stroma microenvironment.
Interplay between partner and ligand facilitates the folding and binding of an intrinsically disordered protein
Authors: Rogers Joseph M. , Oleinikovas Vladimiras , Shammas Sarah L. , Wong Chi T. , De Sancho David , Baker Christopher M. , Clarke Jane
Published: October 2014

Significance

Specific protein–protein interactions are abundant in, and essential for, cellular life. In contrast to the well-studied docking of two already folded proteins, it has been recently established that many proteins are disordered and unfolded in the absence of their partner protein, but appear folded once bound. Must these initially disordered proteins transiently fold in isolation before binding their partners? We examine a small disordered protein and find that interactions with its (already structured) partner protein are what cause the relatively unstructured protein to fold. Thus, the requirement for one protein to fold is not an obstacle for reliable, fast association between two proteins. This result offers some explanation for the abundance of similar protein–protein interactions throughout biology.
Protein−DNA binding in the absence of specific base-pair recognition
Authors: Afek Ariel , Schipper Joshua L. , Horton John , Gordân Raluca , Lukatsky David B.
Published: October 2014

Significance

Understanding molecular mechanisms of how regulatory proteins, called transcription factors (TFs), recognize their specific binding sites encoded into genomic DNA represents one of the central, long-standing problems of molecular biophysics. Strikingly, our experiments demonstrate that DNA context characterized by certain repeat symmetries surrounding specific TF binding sites significantly influences binding specificity. We expect that our results will significantly impact the understanding of molecular, biophysical principles of transcriptional regulation, and significantly improve our ability to predict how variations in DNA sequences, i.e., mutations or polymorphisms, and protein concentrations influence gene expression programs in living cells.
Long-term relationships among pesticide applications, mobility, and soil erosion in a vineyard watershed
Authors: Sabatier Pierre , Poulenard Jérôme , Fanget Bernard , Reyss Jean-Louis , Develle Anne-Lise , Wilhelm Bruno , Ployon Estelle , Pignol Cécile , Naffrechoux Emmanuel , Dorioz Jean-Marcel , Montuelle Bernard , Arnaud Fabien
Published: October 2014

Significance

A record of lake sediment spanning approximately 100 years allowed us to reconstruct the long-term succession of herbicide, fungicide, and insecticide treatments in a vineyard catchment in France. This record of pesticide deposition is consistent with the historical onset and banning of these chemical substances by French and European environmental agencies. We also present evidence of the effects of postemergence herbicides, such as glyphosate, on soil erosion and evidence of the release of banned remnant pesticides, such as dichlorodiphenyltrichloroethane (DDT), that are stored in vineyard soil back into the environment. These results indicate that the sink–source dynamics of pesticides, which are crucial in ecotoxicological risk assessment, should take into account the effects of a changing environment on pesticide storage.