bluuebunny/crossref_metadata_2025 huggingface dataset:
Microfluidics as A Tool to Understand the Build‐Up Mechanism of Exponential‐Like Growing Films
Authors: Madaboosi Narayanan , Uhlig Katja , Jäger Magnus S. , Möhwald Helmuth , Duschl Claus , Volodkin Dmitry V.
Published: July 2012

Microfluidics is used here for the first time to efficiently tune the growth conditions for understanding the build‐up mechanism of exponentially growing polyelectrolyte (PE) films. The velocity of PE supply and time of interaction can be successfully altered during the layer‐by‐layer assembly. Another advantage of this method is that the deposition of poly‐L‐lysine/hyaluronic acid (PLL/HA) films in microchannels can be monitored online by fluorescence microscopy. The study demonstrates that PE mass transport to the film surface and diffusion in the film are key parameters affecting PLL/HA film build‐up. Increase of PE supply rate results in a change in the “transition” (exponential‐to‐linear growth) towards higher number of deposition steps, thus indicating a mass transport‐mediated growth mechanism.
The pathophysiology of echopraxia/echolalia: Relevance to Gilles De La Tourette syndrome
Authors: Ganos Christos , Ogrzal Timo , Schnitzler Alfons , Münchau Alexander
Published: July 2012

Echopraxia and echolalia are subsets of imitative behavior. They are essential developmental elements in social learning. Their persistence or reemergence after a certain age, though, can be a sign of underlying brain dysfunction. Although echophenomena have been acknowledged as a typical sign in Gilles de la Tourette syndrome (GTS) since its first description, their clinical significance and neural correlates are largely unknown. Here, we review the course of their scientific historical development and focus on their clinical phenomenology and differential diagnosis with a particular view to GTS. The neural basis of echophenomena will also be addressed. © 2012 Movement Disorder Society
Novel chipless RF identification technology for on‐touch data transfer applications
Authors: Nair Sreejith M. , Shameena V. A. , Nijas M. , Mohanan P.
Published: July 2012

This article presents the design and development of a simple low‐cost chipless RFID system for secure near field data transfer.This system is ideal for use in credit cards, personal data keeping cards, and similar identification cards which are based on “data transfer by contact” which at present commonly uses the integrated circuits or magnetic strips in it. The proposed system consists of a compactable low‐cost RFID tag and a reader using a rectangular waveguide. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2325–2327, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27044
Erratum: Compact wideband LTCC bandstop filter using vertical coupled‐line units
Authors: Qian Kewei , Tang Xiao‐Hong
Published: July 2012

Original article published Microwave Opt Technol Lett 54:1173–1176, 2012.© 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54: 2445, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27047 (Original article DOI 10.1002/mop.26787)
A miniaturized switchable circularly polarized patch antenna controlled by a single diode operation
Authors: Pyo Seongmin , Shin Imseob
Published: July 2012

A novel switchable circularly polarized patch antenna with a compact size is proposed that uses only a single PIN diode. The proposed antenna consists of a corner‐truncated square radiating patch with a cross‐shaped slot on the ground, a triangular conductor, and one PIN diode. Because of the cross ground slot which is embedded on the diagonal direction, the resonant frequencies of each circular polarization sense are lowered about 41% for right‐hand circular polarization and 38% for left‐hand circular polarization. Moreover, by alternating the states of only one diode, a circular polarization sense is easily reconfigured without a radiating degradation. The simulated and measured results show that good CP characteristics are obtained with symmetrical radiation patterns at the lowered resonant frequencies. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2375–2378, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27070
Dual‐mode dual‐band bandpass filter design using open‐loop resonators
Authors: Liu Haiwen , Zhao Yulong , Shi Liyun , Luo Hui
Published: July 2012

This letter presents a novel dual‐band bandpass filter using dual‐mode open‐loop resonator. Non‐degenerate modes of the dual‐mode resonator are excited by loading a center‐loaded T‐shaped stub and its nature is investigated through the even‐odd mode analysis. Based on the aforementioned dual‐mode resonators, a compact dual‐band filter is designed. Results verify that the fabricated filter with the central frequencies of 1.8 and 2.4 GHz and the fractional bandwidth of 8.3 and 12.9% are obtained. Also, there are several transmission zeros located at both sides of each passband. It provides the filter with improved selectivity and stopband suppression. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2370–2372, 2012; View this article online at wileyonlinelibrary.com.. DOI 10.1002/mop.27080
Anomalous forerunners in wave propagation: A temporal analysis
Authors: Ranfagni Anedio , Cacciari Ilaria , Agresti Alessandro , Mignani Roberto , Petrucci Andrea
Published: July 2012

The problem of the interpretation of anomalous forerunners as observed in microwave propagation experiments is re‐examined within the framework of a simpler model as compared to the one previously adopted. Furthermore, a time‐dependent analysis according to a saddle‐point procedure is developed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2246–2248, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27083
Predicting infinite periodic structure properties from finite structure models
Authors: Ethier J. , McNamara D. A.
Published: July 2012

Many techniques have been proposed for determining the properties of a finite‐sized periodic structure from one consisting of the same elements and lattice, but infinite in size. In this article, we do the opposite, and describe an easily implemented moment method approach to determine the infinite structure properties from a related finite one, but importantly without the necessity of finding the current distribution on any element other than a single central one, and only having to find the solution of a matrix equation whose size is determined by the number of unknowns associated with the central element only. This is useful if one has access to a formulation (and source code) to analyze a single element and wish to know the properties of an infinite periodic structure comprised of such elements. Numerical validation is provided. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2416–2420, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27094
Estimating T1 from multichannel variable flip angle SPGR sequences
Authors: Trzasko Joshua D. , Mostardi Petrice M. , Riederer Stephen J. , Manduca Armando
Published: July 2012

Quantitative estimation of T1 is a challenging but important task inherent to many clinical applications. The most commonly used paradigm for estimating T1 in vivo involves performing a sequence of spoiled gradient‐recalled echo acquisitions at different flip angles, followed by fitting of an exponential model to the data. Although there has been substantial work comparing different fitting methods, there has been little discussion on how these methods should be applied for data acquired using multichannel receivers. In this note, we demonstrate that the manner in which multichannel data is handled can have a substantial impact on T1 estimation performance and should be considered equally as important as choice of flip angles or fitting strategy. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Simultaneous multislice inversion contrast imaging using power independent of the number of slices (PINS) and delays alternating with nutation for tailored excitation (DANTE) radio frequency pulses
Authors: Koopmans Peter J. , Boyacioğlu Rasim , Barth Markus , Norris David G.
Published: July 2012

A method for simultaneous multislice (SMS) inversion contrast imaging is presented using a combination of the delays alternating with nutation for tailored excitation (DANTE) and the power independent of the number of slices (PINS) techniques. In SMS imaging, simultaneously excited slices result in an aliased image that is disentangled using parallel imaging reconstruction techniques. At high‐magnetic field strengths, the peak amplitude and specific absorption rate of conventional (summed) SMS radio frequency pulses can be prohibitively high. Using the PINS approach, specific absorption rate is independent of the number of slices allowing high SMS acceleration factors even at high fields. Using DANTE, adiabatic SMS radio frequency pulses can be created to be combined with PINS. This allows 2D imaging protocols that employ adiabatic pulses to also reap the benefits of low specific absorption rate SMS acceleration. As a proof‐of‐concept, simulations and measurements using hyperbolic secant inversion pulses are shown. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Hybrid ultra‐low‐field MRI and magnetoencephalography system based on a commercial whole‐head neuromagnetometer
Authors: Vesanen Panu T. , Nieminen Jaakko O. , Zevenhoven Koos C. J. , Dabek Juhani , Parkkonen Lauri T. , Zhdanov Andrey V. , Luomahaara Juho , Hassel Juha , Penttilä Jari , Simola Juha , Ahonen Antti I. , Mäkelä Jyrki P. , Ilmoniemi Risto J.
Published: July 2012

Ultra‐low‐field MRI uses microtesla fields for signal encoding and sensitive superconducting quantum interference devices for signal detection. Similarly, modern magnetoencephalography (MEG) systems use arrays comprising hundreds of superconducting quantum interference device channels to measure the magnetic field generated by neuronal activity. In this article, hybrid MEG‐MRI instrumentation based on a commercial whole‐head MEG device is described. The combination of ultra‐low‐field MRI and MEG in a single device is expected to significantly reduce coregistration errors between the two modalities, to simplify MEG analysis, and to improve MEG localization accuracy. The sensor solutions, MRI coils (including a superconducting polarizing coil), an optimized pulse sequence, and a reconstruction method suitable for hybrid MEG‐MRI measurements are described. The performance of the device is demonstrated by presenting ultra‐low‐field‐MR images and MEG recordings that are compared with data obtained with a 3T scanner and a commercial MEG device. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
The Gilbert arborescence problem
Authors: Volz M. G. , Brazil M. , Ras C. J. , Swanepoel K. J. , Thomas D. A.
Published: July 2012

We investigate the problem of designing a minimum‐cost flow network interconnecting n sources and a single sink, each with known locations in a normed space and with associated flow demands. The network may contain any finite number of additional unprescribed nodes from the space; these are known as the Steiner points. For concave increasing cost functions, a minimum‐cost network of this sort has a tree topology, and hence can be called a Minimum Gilbert Arborescence (MGA). We characterize the local topological structure of Steiner points in MGAs, showing, in particular, that for a wide range of metrics, and for some typical real‐world cost functions, the degree of each Steiner point is 3. © 2012 Wiley Periodicals, Inc. NETWORKS, 2013
Epigenetic regulation of DACT2, a key component of the Wnt signalling pathway in human lung cancer
Authors: Jia Yan , Yang Yunsheng , Brock Malcolm V , Zhan Qimin , Herman James G , Guo Mingzhou
Published: July 2012

Dapper, Dishevelled‐associated antagonist of β‐catenin (DACT), is involved in Xenopus embryonic development. Human DACT2 is localized on chromosome 6q27, a region of frequent loss of heterozygosity (LOH) in human cancers. However, the function and regulation of DACT2 in human lung cancer remain unclear. DNA sequencing, methylation‐specific PCR (MSP), semi‐quantitative RT‐PCR, western blotting, and xenograft models were employed in this study. Eight lung cancer cell lines, 106 cases of primary lung cancer, four specimens of normal lung from patients without cancer, and 99 blood samples from healthy individuals were examined. We found that while there was no SNP related to lung cancer, the DACT2 promoter region is frequently methylated in human lung cancer. DACT2 is silenced by promoter region hypermethylation and re‐expressed by 5‐aza‐2′‐deoxyazacytidine treatment of lung cancer cell lines. Methylation of DACT2 was associated with poor differentiation of lung cancer. Loss of DACT2 expression was associated with promoter region hypermethylation in primary lung cancer, and was associated with increased β‐catenin expression. Restoration of DACT2 expression suppressed tumour proliferation both in vitro and in vivo. DACT2 expression was down‐regulated by siRNA knockdown in H727 cells. DACT2 inhibited T‐cell factor/lymphoid enhancer factor (TCF/LEF) and its downstream genes. In conclusion, DACT2 methylation is a potential lung cancer detection marker. DACT2 is regulated by promoter region hypermethylation. DACT2 inhibits lung cancer proliferation by suppressing the Wnt signalling pathway in lung cancer. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
A chiral polymer‐based turn‐on fluorescent sensor for specific recognition of hydrogen sulfate
Authors: Chen Dan , Lu Wei , Du Ganhong , Jiang Liming , Ling Jun , Shen Zhiquan
Published: July 2012

A new kind of polymeric chemosensor containing chiral naphthaldimine moiety in the side chain was synthesized by the reversible addition‐fragmentation chain transfer polymerization of N‐{[2‐(4‐vinylbenzyloxy)‐1‐naphthyl]‐methylene}‐(S)‐2‐phenylglycinol (VNP). The resulting polymers (PVNP) showed high selectivity for hydrogen sulfate relative to other anions including F−, Cl−, Br−, H2PO, CH3CO, and NO in tetrahydrofuran (THF) solution as judged from UV−vis, fluorescence, and circular dichroism spectrophotometric titrations. Compared with its monomer, the polymer has proven to be more attractive for detection of HSO in terms of sensitivity and reproducibility. Upon addition of the anion it gives remarkable spectral responses concomitant with detectable color change from colorless to pale yellow. Furthermore, the HSO‐induced CD or fluorescence signal can be totally reversed with addition of base and eventually recovered the initial state, leading to a reproducible molecular switch with two distinguished “on” and “off” states. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Domain organization of XAF1 and the identification and characterization of XIAPRING‐binding domain of XAF1
Authors: Tse Man Kit , Cho Chi Kong , Wong Wai Fung , Zou Bing , Hui Sin Kam , Wong Benjamin Chun Yu , Sze Kong Hung
Published: July 2012

X‐linked inhibitor of apoptosis protein (XIAP)‐associated factor 1 (XAF1) has been implicated as a novel tumor suppressor, which was proposed to exert pro‐apoptotic effect by antagonizing the anticaspase activity of XIAP. Here, we delineated the domain architecture of XAF1 by applying limited proteolysis and peptide mass fingerprinting analysis. Our results indicated that XAF1 has a distinct domain organization, with a highly compact N‐terminal domain (XAF1NTD) followed by a middle domain (XAF1MD), a 42‐residue unstructured linker and a C‐terminal domain (XAF1CTD). The search of XIAP binding region within XAF1 revealed that a modest affinity XIAPRING binding site (dissociation constant, Kd, ∼18 μM) is located at the C‐terminal portion of XAF1. This C‐terminal region, embracing XAF1CTD and a flexible tail at C‐terminus (residue Thr251‐Ser301), is functionally identified as XIAPRING‐binding domain of XAF1 (XAF1RBD) in the present study. We have also mapped the interaction sites for XAF1RBD on XIAPRING by using NMR spectroscopy. By applying in vitro ubiquitination assay, we observed that XAF1RBD/XIAP interaction is essential for the ubiquitination of GST‐XAF1RBD fusion protein. In addition, the C‐terminal XAF1 fragment harboring XAF1RBD was found to be substantially ubiquitinated by XIAPRING. Base on these observations, we speculate a possible role of XAF1RBD in targeting XAF1 for XIAP‐mediated ubiquitination.
Synthesis of short cationic antimicrobial peptidomimetics containing arginine analogues
Authors: Baldassarre Leonardo , Pinnen Francesco , Cornacchia Catia , Fornasari Erika , Cellini Luigina , Baffoni Marina , Cacciatore Ivana
Published: July 2012

Worldwide efforts are underway to develop new antimicrobial agents against bacterial resistance. To identify new compounds with a good antimicrobial profile, we designed and synthesized two series of small cationic antimicrobial peptidomimetics (1–8) containing unusual arginine mimetics (to introduce cationic charges) and several aromatic amino acids (bulky moieties to improve lipophilicity). Both series were screened for in vitro antibacterial activity against a representative panel of Gram‐positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram‐negative (Escherichia coli and Klebsiella pneumoniae) bacterial strains, and Candida albicans. The biological screening showed that peptidomimetics containing tryptophan residues are endowed with the best antimicrobial activity against S. aureus and S. epidermidis in respect to the other synthesized derivatives (MIC values range 7.5–50 µg/ml). Moreover, small antimicrobial peptidomimetics derivatives 2 and 5 showed an appreciable activity against the tested Gram‐negative bacteria and C. albicans. The most active compounds (1–2 and 5–6) have been tested against Gram‐positive established biofilm, too. Results showed that the biofilm inhibitory concentration values of these compounds were never up to 200 µg/ml. The replacement of tryptophan with phenylalanine or tyrosine resulted in considerable loss of the antibacterial action (compounds 3–4 and 7–8) against both Gram‐positive and Gram‐negative bacterial strains. Furthermore, by evaluating hemolytic activity, the synthesized compounds did not reveal cytotoxic activities, except for compound 5. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Spin hamiltonian models for artificial and native water splitting systems revealed by hybrid DFT calculations. Oxygen activation by high‐valent Mn and Ru ions
Authors: Yamaguchi K. , Yamanaka S. , Isobe H. , Tanaka K. , Ueyama N.
Published: July 2012

Electronic and spin states of putative ruthenium (Ru)–quinine(Q) complex(1) mononuclear[Ru(trpy)(3,5‐t‐Bu2Q)(OH2)(trpy = 2,2′:6′,2″‐terpyridine, 3,5‐di‐tert‐butyl‐1,2‐benzoquinone)(2) and binuclear [Ru2(btpyan)(3,6‐di‐Bu2Q)2(OH2)](SbF6)2 (btpyan = 1,8‐bis(2,2′:6′,2″‐terpyrid‐4′‐yl)anthracene,3,6‐t‐Bu2Q = 3,6‐di‐tert‐butyl‐1,2‐benzoquinone) (3) were investigated by broken‐symmetry (BS) hybrid density functional (DFT) methods. BS DFT computations for 3 have elucidated that the closed‐shell structure (3b): Ru(II)–quinone (Q) complex is less stable than the open‐shell structure (3bb) consisted of Ru(III) and semiquinone fragments. These computations have also elucidated eight different electronic and spin structures of tetraradical intermediates generated in the course of water splitting reaction. The Heisenberg spin Hamiltonian model has been derived to elucidate common theoretical pictures for these systems. Effective exchange interactions for four spin systems have been determined using total energies of the 15 different DFT functionals. The natural orbital (NO) analysis of these BS DFT solutions have also been performed to elucidate the NOs and their occupation numbers that are useful for lucid understanding of the nature of chemical bonds of these Ru complexes (1, 2, and 3). Implications of the computational results are discussed in relation to proposed reaction mechanisms of water splitting reaction in artificial photosynthesis systems, similarity between artificial and native water splitting systems, and elements science of water splitting reaction. © 2012 Wiley Periodicals, Inc.
TiO2 photocatalytic degradation of cholesterol: SIMS study
Authors: Prochazka M. , Stupavska M. , Jerigova M. , Velic D.
Published: July 2012

TiO2 is an efficient photocatalyst for chemical degradation. Nanocrystalline TiO2 is used in the form of film supported on glass substrate. Since the photocatalytic process is occurring on the surface, a surface‐sensitive technique as a direct probe is desirable. In order to study TiO2 photoactivity and photodegradation of cholesterol, as a model biomolecule, secondary ion mass spectrometry is utilized. Cholesterol (C27H46O), stated as M, with mass of 386.65 u, adsorbed on TiO2 surface, activated with water, and irradiated with different ultraviolet (UV) exposure times is characterized under impact of 25‐keV Bi+ primary ions. The molecular positive ions in the forms of M–OH and M–H with masses of 369.3 u and 385.3 u, respectively, are of main interest. Due to the specific group of OH, the M‐OH molecular ion might be considered as the primary identification species of the intact cholesterol molecule. The intensities of cholesterol fragment ions M–C5H10, M–C7H14, M–C7H14OH, M + C4H7, M + C4H9O, M + C4H9O2, M + C8H15, and 2 M–2(C8H17), 2 M–2(C7H15) decrease significantly after 7 h of UV exposure. Intensities of M–OH and M–H peaks decrease after 24 h by 88% and 62%, respectively. These measurements show the potential to degrade cholesterol, as a main bacteria membrane component and in such a way to terminate bacteria effectively. Copyright © 2012 John Wiley & Sons, Ltd.
Evaluation of diagnostic results by Bayes' theorem
Authors: Shindo Takatoshi , Takahashi Tsuguhiro , Okamoto Tatsuki , Kuraishi Takashi
Published: July 2012

Application of Bayes' theorem for the evaluation of diagnostic results of electric facilities is described. A concept of risk assessment method based on the diagnosis results is proposed and the effects of various parameters on the risk are clarified. Based on these results, a rational renewal scheme using diagnostic results is proposed. In addition, the prior probability based on the data of actual facilities is investigated and it is found that the data available so far is insufficient and more data are required for the detailed analysis. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Prediction of early and late pre‐eclampsia from maternal characteristics, uterine artery Doppler and markers of vasculogenesis during first trimester of pregnancy
Authors: Parra‐Cordero M. , Rodrigo R. , Barja P. , Bosco C. , Rencoret G. , Sepúlveda‐Martinez A. , Quezada S.
Published: July 2012

Objective

To develop a predictive model for pre‐eclampsia using clinical, biochemical and ultrasound markers during the first trimester of pregnancy.

Methods

This was a nested case–control study within a pre‐eclampsia screening project that involved 5367 asymptomatic pregnant women undergoing routine transvaginal uterine artery (UtA) Doppler at 11 + 0 to 13 + 6 weeks. Following exclusions, there were 70 pregnant women who later developed pre‐eclampsia and 289 control patients enrolled during the first trimester who had serum or plasma samples taken at enrolment available for the purposes of this study. Of these, 17 pregnancies were diagnosed with early‐onset (delivery < 34 weeks) pre‐eclampsia and 53 with late‐onset (delivery ≥ 34 weeks) pre‐eclampsia. The lowest, highest and mean of left and right UtA pulsatility indices (PI) were calculated. Blood samples were stored at −84 °C until biochemical analysis for markers of vasculogenesis was performed. The distributions of the lowest UtA‐PI and the biochemical markers were adjusted for maternal characteristics, expressed as multiples of the median (MoM), and compared between groups. Logistic regression analysis was used to evaluate if any variable was significantly associated with pre‐eclampsia.

Results

Pregnancies that later developed pre‐eclampsia were associated with higher maternal prepregnancy body mass index. An increased lowest UtA‐PI was significantly associated with both early‐ and late‐onset disease. Placental growth factor (PlGF) MoM was significantly reduced in women who later developed early‐ or late‐onset pre‐eclampsia compared with controls (median (interquartile range), 0.69 (0.33–1.46) and 1.10 (0.39–1.56), respectively, vs 1.19 (0.65–1.84), P < 0.05). Different combined models were generated by logistic regression analysis, and the detection rate with a fixed 10% false‐positive rate was 47% and 29% for early‐ and late‐onset pre‐eclampsia, respectively.

Conclusion

Pregnancies that later developed early or late pre‐eclampsia were characterized by impaired placentation and an anti‐angiogenic state during the first trimester of pregnancy. Regression models which include maternal characteristics, UtA Doppler and PlGF can apparently predict approximately half of pregnancies that will be complicated by early‐onset pre‐eclampsia. We believe more research in several areas is needed to aid in the creation of a better and more population‐specific screening test for pre‐eclampsia during the first trimester of pregnancy. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Expanding the Series of [RE2Ca(OQ)8] Structures: New Heterobimetallic Rare Earth/Alkaline Earth 8‐Quinolinolate Complexes
Authors: Deacon Glen B. , Junk Peter C. , Leary Stuart G. , Urbatsch Aron
Published: July 2012

Abstract. A series of heterobimetallic complexes [RE2Ca(OQ)8]·nHOQ(RE = Sm, Gd, Tb, Ho, Tm, Yb, Lu, Y, Sc) and the isostructural [Gd2Mg(OQ)8] were synthesised and structurally characterised. They were mainly obtained after direct reactions of the elemental rare earth metals with calcium metal in the presence of 8‐hydroxyquinoline (HOQ) and a 1, 3, 5‐tri‐tert‐butyl‐benzene (tBuB) flux, and some complexes were synthesised by pseudo solid‐state rearrangement reactions between powdered RE(OQ)3 and AE(OQ)2 (AE = Mg, Ca) in a 1, 2, 4, 5‐tetramethylbenzene (TMB) flux, at elevated temperatures. The linear trinuclear [RE2Ca(OQ)8] moieties show a six‐coordinate central calcium atom flanked by two eight‐coordinate rare earth atoms surrounded by six chelating‐bridging OQ and two terminal chelating OQ ligands. The structurally novel [Sc2Ca(OQ)8] has a bent Sc‐Ca‐Sc backbone and exhibits an eight‐coordinate central calcium and two seven‐coordinate scandium ions.
Foliar herbivory and its effects on plant growth in native and exotic species in the Patagonian steppe
Authors: Pirk Gabriela Inés , Farji‐Brener Alejandro G.
Published: July 2012

Studies of herbivory and its consequences on the growth of native and exotic plants could help elucidate some processes involved in plant invasions. Introduced species are likely to experience reduced herbivory in their new range due to the absence of specialist enemies and, thus, may have higher benefits if they reduce the investment in resistance and increase their compensatory capacity. In order to evaluate the role of herbivory in disturbed areas within the Patagonian steppe, we quantified and compared the leaf levels of herbivory of four native and five exotic species and recorded the associated insect fauna. We also performed greenhouse experiments in which we simulated herbivory in order to evaluate the compensatory capacity of native and exotic species under different herbivory levels that resembled naturally occurring damage. Natural herbivory levels in the field were similar between the studied exotic and native plants. Field observations confirmed that they both shared some herbivore insects, most of which are generalists. In the greenhouse experiments, both exotic and native plants fully compensated for herbivory. Our results suggest that the studied exotic plants are not released from herbivory in the Patagonian steppe but are able to fully compensate for it. The capacity to recover from herbivory coupled with other potential adaptations, such as a better performance under disturbance and greater competitive ability than that of the native species, may represent some of the mechanisms responsible for the success of plant invasion in the Patagonian steppe.
Genetische Epidemiologie: Über kleine und große genetische Risiken
Authors: Heid Iris M.
Published: July 2012

Einleitung

Die Genetische Epidemiologie untersucht genetische Komponenten für komplexe Erkrankungen und deren Interaktionen mit nicht-genetischen Faktoren. In den letzten Jahren war die Methode der genomweiten Assoziationsstudien sehr erfolgreich, um zahlreiche Genorte für komplexe Erkrankungen zu identifizieren. Am Beispiel der altersbedingten Maculadegeneration und der Adipositas wird dargelegt, wie groß diese genetischen Effekte sind.
Experimental characterization of three-dimensional corner flows at low Reynolds numbers
Authors: Sznitman J. , Guglielmini L. , Clifton D. , Scobee D. , Stone H. A. , Smits A. J.
Published: July 2012

We investigate experimentally the characteristics of the flow field that develops at low Reynolds numbers ($\mathit{Re}\ll 1$) around a sharp $9{0}^{\ensuremath{\circ} } $ corner bounded by channel walls. Two-dimensional planar velocity fields are obtained using particle image velocimetry (PIV) conducted in a towing tank filled with a silicone oil of high viscosity. We find that, in the vicinity of the corner, the steady-state flow patterns bear the signature of a three-dimensional secondary flow, characterized by counter-rotating pairs of streamwise vortical structures and identified by the presence of non-vanishing transverse velocities (${u}_{z} $). These results are compared to numerical solutions of the incompressible flow as well as to predictions obtained, for a similar geometry, from an asymptotic expansion solution (Guglielmini et al., J. Fluid Mech., vol. 668, 2011, pp. 33–57). Furthermore, we discuss the influence of both Reynolds number and aspect ratio of the channel cross-section on the resulting secondary flows. This work represents, to the best of our knowledge, the first experimental characterization of the three-dimensional flow features arising in a pressure-driven flow near a corner at low Reynolds number.
Justice, Disagreement and Democracy
Authors: Valentini Laura
Published: July 2012

Is democracy a requirement of justice or an instrument for realizing it? This article argues that the correct answer to this question depends on the background circumstances against which democracy is defended. In the presence ofthin reasonable disagreementabout justice, we should value democracy only instrumentally (if at all); in the presence ofthick reasonable disagreementabout justice, we should value it also intrinsically, as a necessary demand of justice. Since the latter type of disagreement is pervasive in real-world politics, the conclusion is that theories of justice designed for our world should be centrally concerned with democracy.
New genetic resource in Capsicum L. from Eastern Himalayas
Authors: Baran Jha Timir , Dafadar Arpita , Ghorai Animesh
Published: July 2012

A well-documented karyo-morphological analysis has been presented in one unexplored cultivar of Capsicum annuum L., collected from South Sikkim, India, to determine the chromosome number. This report confirms that the cultivar contains 2n = 48 chromosomes, which are not produced through self-duplication. More studies are required to determine its actual taxonomic position and genetic relationship with other cultivars and species. This cultivar of C. annuum provides a new, unexplored genetic resource with a high chromosome number.
Screening a diverse collection ofArtemisia annuagermplasm accessions for the antimalarial compound, artemisinin
Authors: Cockram James , Hill Colin , Burns Corrinne , Arroo Randoph R. J. , Woolley Jack G. , Flockart Ian , Robinson Trevor , Atkinson Christopher J. , Davies Michael J. , Dungey Nigel , Greenland Andy J. , Smith Lydia L. M. J. , Bentley Steven
Published: July 2012

The antimalarial drug artemisinin (ART) is commercially extracted from the medicinal plantArtemisia annuaL. Here, we report the screening of 70A. annuaplants representing 14 diverse germplasm accessions sourced from around the world, and identify lines containing >2% ART. These extremely high-yielding individuals have been maintained as vegetative clones, and they represent promising germplasm resources for futureA. annuabreeding programmes.
Variants in the LEPR Gene Are Nominally Associated With Higher BMI and Lower 24‐h Energy Expenditure in Pima Indians
Authors: Traurig Michael T. , Perez Jessica M. , Ma Lijun , Bian Li , Kobes Sayuko , Hanson Robert L. , Knowler William C. , Krakoff Jonathan A. , Bogardus Clifton , Baier Leslie J.
Published: July 2012

Genome‐wide association studies (GWASs) have been used to search for susceptibility genes for type 2 diabetes and obesity in the Pima Indians, a population with a high prevalence of both diseases. In these studies, a variant (rs2025804) in the LEPR gene was nominally associated with BMI in 1,082 subjects (P = 0.03 adjusted for age, sex, birth year, and family membership). Therefore the LEPR and leptin overlapping transcript (LEPROT) genes were selected for further sequencing and genotyping in larger population‐based samples for association analyses with obesity‐related phenotypes. Selected variants (n = 80) spanning these genes were genotyped in a sample of full‐heritage Pima Indians (n = 2,842) and several common variants including rs2025804 were nominally associated with BMI (P = 0.05–0.003 adjusted for age, sex, birth year, and family membership). Four common tag variants associated with BMI in the full‐heritage Pima Indian sample were genotyped in a second sample of mixed‐heritage Native Americans (n = 2,969) and three of the variants showed nominal replication (P = 0.03–0.006 adjusted as above and additionally for Indian heritage). Combining both samples provided the strongest evidence for association (adjusted P = 0.0003–0.0001). A subset of these individuals (n = 403) had been metabolically characterized for predictors of obesity and the BMI risk alleles for the variants tagged by rs2025804 were also associated with lower 24‐h energy expenditure (24hEE) as assessed in a human respiratory chamber (P = 0.0007 adjusted for age, sex, fat mass, fat‐free mass, activity, and family membership). We conclude that common noncoding variation in the LEPR gene is associated with higher BMI and lower energy expenditure in Native Americans.
The role of UBL domains in ubiquitin-specific proteases
Authors: Faesen Alex C. , Luna-Vargas Mark P.A. , Sixma Titia K.
Published: July 2012

Ubiquitin conjugation and deconjugation provides a powerful signalling system to change the fate of its target enzymes. Ubiquitination levels are organized through a balance between ubiquitinating E1, E2 and E3 enzymes and deubiquitination by DUBs (deubiquitinating enzymes). These enzymes are tightly regulated to control their activity. In the present article, we discuss the different ways in which DUBs of the USP (ubiquitin-specific protease) family are regulated by internal domains with a UBL (ubiquitin-like) fold. The UBL domain in USP14 is important for its localization at the proteasome, which enhances catalysis. In contrast, a UBL domain in USP4 binds to the catalytic domain and competes with ubiquitin binding. In this process, the UBL domain mimics ubiquitin and partially inhibits catalysis. In USP7, there are five consecutive UBL domains, of which the last two affect catalytic activity. Surprisingly, they do not act like ubiquitin and activate catalysis rather than inhibiting it. These C-terminal UBL domains promote a conformational change that allows ubiquitin binding and organizes the catalytic centre. Thus it seems that UBL domains have different functions in different USPs. Other proteins can modulate the roles of UBL domains in USP4 and USP7. On one hand, the inhibition of USP4 can be relieved when the UBL is sequestered by another USP. On the other, the activation of USP7 is increased, when the UBL-activated state is stabilized by allosteric binding of GMP synthetase. Altogether, UBL domains appear to be able to regulate catalytic activity in USPs, but they can use widely different mechanisms of action, in which they may, as in USP4, or may not, as in USP7, use the direct resemblance to ubiquitin.
Mycobacterium tuberculosis cytochrome P450 enzymes: a cohort of novel TB drug targets
Authors: Hudson Sean A. , McLean Kirsty J. , Munro Andrew W. , Abell Chris
Published: July 2012

TB (tuberculosis) disease remains responsible for the death of over 1.5 million people each year. The alarming emergence of drug-resistant TB has sparked a critical need for new front-line TB drugs with a novel mode of action. In the present paper, we review recent genomic and biochemical evidence implicating Mycobacterium tuberculosis CYP (cytochrome P450) enzymes as exciting potential targets for new classes of anti-tuberculars. We also discuss HTS (high-throughput screening) and fragment-based drug-discovery campaigns that are being used to probe their potential druggability.
Thermodynamic scaling of α-relaxation time and viscosity stems from the Johari-Goldstein β-relaxation or the primitive relaxation of the coupling model
Authors: Ngai K. L. , Habasaki J. , Prevosto D. , Capaccioli S. , Paluch Marian
Published: July 2012

By now it is well established that the structural α-relaxation time, τα, of non-associated small molecular and polymeric glass-formers obey thermodynamic scaling. In other words, τα is a function Φ of the product variable, ργ/T, where ρ is the density and T the temperature. The constant γ as well as the function, τα = Φ(ργ/T), is material dependent. Actually this dependence of τα on ργ/T originates from the dependence on the same product variable of the Johari-Goldstein β-relaxation time, τβ, or the primitive relaxation time, τ0, of the coupling model. To support this assertion, we give evidences from various sources itemized as follows. (1) The invariance of the relation between τα and τβ or τ0 to widely different combinations of pressure and temperature. (2) Experimental dielectric and viscosity data of glass-forming van der Waals liquids and polymer. (3) Molecular dynamics simulations of binary Lennard-Jones (LJ) models, the Lewis–Wahnström model of ortho-terphenyl, 1,4 polybutadiene, a room temperature ionic liquid, 1-ethyl-3-methylimidazolium nitrate, and a molten salt 2Ca(NO3)2·3KNO3 (CKN). (4) Both diffusivity and structural relaxation time, as well as the breakdown of Stokes-Einstein relation in CKN obey thermodynamic scaling by ργ/T with the same γ. (5) In polymers, the chain normal mode relaxation time, τN, is another function of ργ/T with the same γ as segmental relaxation time τα. (6) While the data of τα from simulations for the full LJ binary mixture obey very well the thermodynamic scaling, it is strongly violated when the LJ interaction potential is truncated beyond typical inter-particle distance, although in both cases the repulsive pair potentials coincide for some distances.
Photodetachment and electron reactivity in 1-methyl-1-butyl-pyrrolidinium bis(trifluoromethylsulfonyl)amide
Authors: Molins i Domenech Francesc , FitzPatrick Benjamin , Healy Andrew T. , Blank David A.
Published: July 2012

The transient absorption spectrum in the range 500 nm–1000 nm was measured with ultrafast time resolution on a flowing neat, aliphatic, room-temperature ionic liquid following anion photodetachment. In this region the spectrum was shown to be a combination of absorption from the electron and the hole. Spectrally-resolved electron quenching determined a bimodal shape for the hole spectrum in agreement with recent computational predictions on a smaller aliphatic ionic liquid [Margulis et al., J. Am. Chem. Soc. 133, 20186 (2011)]10.1021/ja203412v. For time delays beyond 15 ps, spectral evolution qualitatively agrees with recent radiolysis experiments [Wishart et al., Faraday Discuss. 154, 353 (2012)10.1039/c1fd00065a]. However, the shape of the spectrum is different, reflecting the contrast in ionization energy between the two methods. Previously unobserved reactivity of the electron was found with a time constant of 300 fs. The results demonstrate solvent control of the rate coefficient for reaction between the electron and proton, with a rapid decline in the rate within the first picosecond.
Compression of a spherically symmetric deuterium-tritium plasma liner onto a magnetized deuterium-tritium target
Authors: Santarius J. F.
Published: July 2012

Converging plasma jets may be able to reach the regime of high energy density plasmas (HEDP). The successful application of plasma jets to magneto-inertial fusion (MIF) would heat the plasma by fusion products and should increase the plasma energy density. This paper reports the results of using the University of Wisconsin’s 1-D Lagrangian, radiation-hydrodynamics, fusion code BUCKY to investigate two MIF converging plasma jet test cases originally analyzed by Samulyak et al. [Physics of Plasmas 17, 092702 (2010)]. In these cases, 15 cm or 5 cm radially thick deuterium-tritium (DT) plasma jets merge at 60 cm from the origin and converge radially onto a DT target magnetized to 2 T and of radius 5 cm. The BUCKY calculations reported here model these cases, starting from the time of initial contact of the jets and target. Compared to the one-temperature Samulyak et al. calculations, the one-temperature BUCKY results show similar behavior, except that the plasma radius remains about twice as long near maximum compression. One-temperature and two-temperature BUCKY results differ, reflecting the sensitivity of the calculations to timing and plasma parameter details, with the two-temperature case giving a more sustained compression.
Thermal switching field distribution of a single domain particle for field-dependent attempt frequency
Authors: Breth L. , Suess D. , Vogler C. , Bergmair B. , Fuger M. , Heer R. , Brueckl H.
Published: July 2012

We present an analytical derivation of the switching field distribution (SFD) at finite temperature for a single domain particle from the Néel-Brown model in the presence of a linearly swept magnetic field. By considering the field dependence of the attempt frequency f0 in the rate equation, we find enhancement of coercivity compared to models using constant f0. The contribution of thermal fluctuations to the standard deviation of the switching field HC derived here reaches values of 10% HC. Considering this contribution, which has been neglected in previous work, is important for the correct interpretation of measurements of switching field distributions.
Nano-scale fracture toughness and behavior of graphene/epoxy interface
Authors: Salahshoor Hossein , Rahbar Nima
Published: July 2012

Atomistic simulations are performed to investigate the nano-scale interfacial fracture toughness between graphene and epoxy. Nano-mechanical properties of graphene and epoxy are initially studied using molecular dynamics simulations. A novel method is suggested to accurately model the behavior of the graphen/epoxy interface during the curing process of the epoxy as a function of temperature. The computed interfacial fracture energy is computed at about 0.203 J/m2, which is in good agreement with available experimental data. It is also shown that the adhesion between cured epoxy and graphene layer increases the pre-existing waviness of the 2-dimensional graphene sheet in a 3-dimensional space. The waviness amplitude is computed to be about 3.23 Å.
Substrate effect on the room-temperature ferromagnetism in un-doped ZnO films
Authors: Zhan Peng , Wang Weipeng , Xie Zheng , Li Zhengcao , Zhang Zhengjun , Zhang Peng , Wang Baoyi , Cao Xingzhong
Published: July 2012

Room-temperature ferromagnetism was achieved in un-doped ZnO films on silicon and quartz substrates. Photoluminescence measurement and positron annihilation analysis suggested that the ferromagnetism was originated from singly occupied oxygen vacancies (roughly estimated as ∼0.55 μB/vacancy), created in ZnO films by annealing in argon. The saturated magnetization of ZnO films was enhanced from ∼0.44 emu/g (on quartz) to ∼1.18 emu/g (on silicon) after annealing at 600 °C, as silicon acted as oxygen getter and created more oxygen vacancies in ZnO films. This study clarified the origin of ferromagnetism in un-doped ZnO and provides an idea to enhance the ferromagnetism.
Phase-field modeling of three-phase electrode microstructures in solid oxide fuel cells
Authors: Li Qun , Liang Linyun , Gerdes Kirk , Chen Long-Qing
Published: July 2012

A phase-field model for describing three-phase electrode microstructure (i.e., electrode-phase, electrolyte-phase, and pore-phase) in solid oxide fuel cells is proposed using the diffuse-interface theory. Conserved composition and non-conserved grain orientation order parameters are simultaneously used to describe the coupled phase coarsening and grain growth in the three-phase electrode. The microstructural evolution simulated by the phase-field approach demonstrates the significant dependence of morphological microstructure and output statistic material features on the prescribed kinetic parameters and three-phase volume fractions. The triple-phase boundary fraction is found to have a major degradation in the early evolution.
Hydrogen Bonding Effects on the Photophysical Properties of 2,3-dihydro-3-keto-1H-pyrido[3,2,1-kl]phenothiazine
Authors: Yang Song-qiu , He Guo-zhong
Published: July 2012

Time-dependent density functional theory (TDDFT) and femtosecond transient absorption spectroscopy were used to investigate the photophysical properties of 2,3-dihydro-3-keto-1H-pyrido[3,2,1-kl]phenothiazine (PTZ4) and 3-keto-1H-pyrido[3,2,1-kl]phenothiazine (PTZ5). The calculated results obtained from TDDFT suggest that the red-shifts of the absorption spectra of these two fluorophores in methanol are due to the formation of hydrogen-bonded complexes at the ground state. Four conformers of PTZ4 were obtained by TDDFT. The two fluorescence peaks of PTZ4 in tetrahydrofuran (THF) came from the ICT states of the four conformers. The fluorescence of PTZ4 in THF showed a dependence on the excitation wavelength because of butterfly bending. The excited state dynamics of PTZ4 in THF and methanol were obtained by transient absorption spectroscopy. The lifetime of the excited PTZ4 in methanol was 53.8 ps, and its relaxation from the LE state to the ICT state was completed within several picoseconds. The short lifetime of excited PTZ4 in methanol was due to the formation of out-of-plane model hydrogen bonds between PTZ4 and methanol at the excited state.
Synthesis of Nitrogen-Doped Graphene via Thermal Annealing Graphene with Urea
Authors: Li Xin-jing , Yu Xin-xin , Liu Jin-yang , Fan Xiao-dong , Zhang Kun , Cai Hong-bing , Pan Nan , Wang Xiao-ping
Published: July 2012

Chemical doping is an effective method to intrinsically modify the chemical and electronic property of graphene. We propose a novel approach to synthesize the nitrogen-doped graphene via thermal annealing graphene with urea, in which the nitrogen source can be controllably released from the urea by varying the annealed temperature and time. The doped N content and the configuration N as well as the thermal stabilities are also evaluated with X-ray photoelectron spectroscopy and Raman spectra. Electrical measurements indicate that the conductivity of doped graphene can be well regulated with the N content. The method is expected to produce large scale and controllable N-doped graphene sheets for a variety of potential applications.