bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving lateral resolution of electrostatic force microscopy by multifrequency method under ambient conditions
Authors: Ding X. D. , An J. , Xu J. B. , Li C. , Zeng R. Y.
Published: June 2009

A multifrequency scanning probe technique which can enhance the spatial resolution of electrostatic force microscopy (EFM) in amplitude-modulation mode under ambient conditions is demonstrated. The first eigenmode of a cantilever is used for topographic imaging, while the second eigenmode is resonantly excited with a sinusoidal modulation voltage applied to the cantilever to measure electrostatic force in lift mode. Two-dimensional images and spectra of electrostatic force are obtained. The lateral resolution of the multifrequency EFM is demonstrated to be better than 15 nm and a theoretical explanation is postulated.
Local, submicron, strain gradients as the cause of Sn whisker growth
Authors: Sobiech M. , Wohlschlögel M. , Welzel U. , Mittemeijer E. J. , Hügel W. , Seekamp A. , Liu W. , Ice G. E.
Published: June 2009

It has been shown experimentally that local in-plane residual strain gradients occur around the root of spontaneously growing Sn whiskers on the surface of Sn coatings deposited on Cu. The strain distribution has been determined with synchrotron white beam micro Laue diffraction measurements. The observed in-plane residual strain gradients in combination with recently revealed out-of-plane residual strain-depth gradients [M. Sobiech et al., Appl. Phys. Lett. 93, 011906 (2008)] provide the driving forces for whisker growth.
Lagrangian particles with mixing. I. Simulating scalar transport
Authors: Klimenko A. Y.
Published: June 2009

The physical similarity and mathematical equivalence of continuous diffusion and particle random walk forms one of the cornerstones of modern physics and the theory of stochastic processes. The randomly walking particles do not need to posses any properties other than location in physical space. However, particles used in many models dealing with simulating turbulent transport and turbulent combustion do posses a set of scalar properties and mixing between particle properties is performed to reflect the dissipative nature of the diffusion processes. We show that the continuous scalar transport and diffusion can be accurately specified by means of localized mixing between randomly walking Lagrangian particles with scalar properties and assess errors associated with this scheme. Particles with scalar properties and localized mixing represent an alternative formulation for the process, which is selected to represent the continuous diffusion. Simulating diffusion by Lagrangian particles with mixing involves three main competing requirements: minimizing stochastic uncertainty, minimizing bias introduced by numerical diffusion, and preserving independence of particles. These requirements are analyzed for two limited cases of mixing between two particles and mixing between a large number of particles. The problem of possible dependences between particles is most complicated. This problem is analyzed using a coupled chain of equations that has similarities with Bogolubov–Born–Green–Kirkwood–Yvon chain in statistical physics. Dependences between particles can be significant in close proximity of the particles resulting in a reduced rate of mixing. This work develops further ideas introduced in the previously published letter [Phys. Fluids 19, 031702 (2007)]. Paper I of this work is followed by Paper II [Phys. Fluids 19, 065102 (2009)] where modeling of turbulent reacting flows by Lagrangian particles with localized mixing is specifically considered.
Effects of solvents and vacancies on the electrical hysteresis characteristics in regioregular poly(3-hexylthiophene) organic thin-film transistors
Authors: Cheng Horng-Long , Lin Wei-Qi , Wu Fu-Chiao
Published: June 2009

The role of residual solvents and vacancies within poly(3-hexylthiophene) (P3HT) active layers, which are made from different boiling point (bp) solvents, on the electrical hysteresis characteristics of P3HT-based transistors was investigated. The improved electrical performance and reduced hysteresis of P3HT films, which are spin coated by high bp solvents, can be interpreted by superior crystalline quality and homogeneity and low vacancies. The hysteresis is dominated by the vacancy-related charge traps in the semiconductor created during film solidification and subsequence solvent evaporation. Furthermore, residual solvents, which initially occupied the vacancies, can contribute to conductivity of regioregular P3HT, thus altering electrical properties and smaller hysteresis.
Waves and turbulence in magnetohydrodynamic direct numerical simulations
Authors: Dmitruk Pablo , Matthaeus W. H.
Published: June 2009

Direct numerical simulations of the incompressible MHD equations with a uniform background magnetic field in a turbulent regime are performed to assess the relative importance of broadband turbulent fluctuations and wavelike fluctuations that are associated with an Alfvén wave dispersion relation. The focus is on properties of the fluctuations in the frequency domain. Eulerian frequency spectra and individual wave number mode frequency spectra show the presence of peaks at the corresponding Alfvén wave frequencies for full nonlinear simulations in a turbulent regime. The peaks are however broad and their power content is compared to the power in the full spectrum as well as a signal to noise ratio is defined and quantified for different values of the background magnetic field. The ratio of power in Alfvén waves to the power in the rest of the spectrum is also quantified and is found to be small for different values of the mean magnetic field. Individual modes in time show a much more complex behavior than that could be expected for linear solutions. Also, nonlinear transfer of energy is evidenced by the existence of peaks at wave numbers perpendicular to the mean magnetic field. Implications are discussed for theories of strong turbulence as well as perturbation theories that assume the leading order behavior is that of propagating Alfvén waves.
Determination of the electrostatic lever arm of carbon nanotube field effect transistors using Kelvin force microscopy
Authors: Brunel David , Deresmes Dominique , Mélin Thierry
Published: June 2009

We use Kelvin force microscopy (KFM) to study the electrostatic properties of single-walled carbon nanotube field effect transistor devices (CNTFETs) with backgate geometry at room temperature. We show that KFM maps recorded as a function of the device backgate polarization enable a complete phenomenological determination of the averaging effects associated with the KFM probe side capacitances, and thus, to obtain KFM measurements with quantitative character. The value of the electrostatic lever arm of the CNTFET is determined from KFM measurements and found in agreement with transport measurements based on Coulomb blockade.
Transport through graphene double dots
Authors: Molitor F. , Dröscher S. , Güttinger J. , Jacobsen A. , Stampfer C. , Ihn T. , Ensslin K.
Published: June 2009

We present Coulomb blockade measurements in a graphene double dot system. The coupling of the dots to the leads and between the dots can be tuned by graphene in-plane gates. The coupling is a nonmonotonic function of the gate voltage. Using a purely capacitive model, we extract all relevant energy scales of the double dot system.
Interface morphologies and interlayer diffusions in organic light emitting device by x-ray scattering
Authors: Lee Young Joo , Park Seong-Sik , Kim Jinwoo , Kim Hyunjung
Published: June 2009

Surface and interface morphologies with thermal expansions and interlayer diffusions in organic light emitting device [LiF/tris-(8-hydroxyquinoline) aluminum (Alq3)/N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine (NPB)/copper phthalocyanine (CuPc)/indium tin oxide/SiO2/glass] were studied by synchrotron x-ray scattering. Interface sharpness and roughness correlation are held under annealing at 100 °C up to 1 h and at 120 °C up to 0.25 h in spite of thermal expansions and interlayer diffusions of NPB and Alq3 layers. The roughness correlation at the interfaces was recovered partially when the interlayer diffusions reach quasisaturation. Crystallization of NPB is hindered due to the interlayer diffusions and appears at much higher temperature than its glass transition.
Improved bulk heterojunction organic solar cells employing C70 fullerenes
Authors: Pfuetzner Steffen , Meiss Jan , Petrich Annette , Riede Moritz , Leo Karl
Published: June 2009

We show that the fullerene C70 is suitable to replace fullerene C60, which is commonly used as electron transporter and acceptor in small-molecule organic solar cells. It is shown that the higher absorption of C70 leads to high external quantum efficiencies of over 50% in the spectral range of 500–700 nm. By optimizing the energy level alignment to hole transport layers, the absorption, and the ratio of C70:zinc phthalocyanine (ZnPc) in a bulk heterojunction solar cell, an efficiency of η=2.87% is achieved. This is a substantial improvement over an identical solar cell employing C60 having η=2.27%. The efficiency increase is due to a higher photocurrent, while fill factor and open-circuit voltage for C70 and C60-containing organic solar cells remain comparable.
Superhydrophobic amorphous carbon/carbon nanotube nanocomposites
Authors: Han Z. J. , Tay B. K. , Shakerzadeh M. , Ostrikov K.
Published: June 2009

Superhydrophobic amorphous carbon/carbon nanotube nanocomposites are fabricated by plasma immersion ion implantation with carbon nanotube forests as a template. The microstructure of the fabricated nanocomposites shows arrays of carbon nanotubes capped with amorphous carbon nanoparticles. Contact angle measurements show that both advancing and receding angles close to 180° can be achieved on the nanocomposites. The fabrication here does not require patterning of carbon nanotubes or deposition of conformal coatings with low surface energy, which are usually involved in conventional approaches for superhydrophobic surfaces. The relationship between the observed superhydrophobicity and the unique microstructure of the nanocomposites is discussed.
Distortion of the intense terahertz signal measured by spectral-encoding technique
Authors: Peng Xiao-Yu , Jung Ralph , Toncian Toma , Willi Oswald , Teng Jing-Hua
Published: June 2009

We demonstrate that a distortion of the terahertz signal measured by spectral-encoding technique occurs when the original signal is too intense. We found that the stronger the original signal is, the more severe the distortion of the retrieved signal will be. Our simulation reproduces this phenomenon and suggests that this distortion, which affects the application of the single-shot terahertz detection technique, comes from the neglect of the quadratic term of the modulation depth which reflects the strength of the terahertz signal in the retrieving process. A possible simple method is proposed to eliminate this distortion.
Reduction of native oxides on GaAs during atomic layer growth of Al2O3
Authors: Lee Hang Dong , Feng Tian , Yu Lei , Mastrogiovanni Daniel , Wan Alan , Gustafsson Torgny , Garfunkel Eric
Published: June 2009

The reduction of surface “native” oxides from GaAs substrates following reactions with trimethylaluminum (TMA) precursor is studied using medium energy ion scattering spectroscopy (MEIS) and x-ray photoelectron spectroscopy (XPS). MEIS measurements after one single TMA pulse show that ∼65% of the native oxide is reduced, confirmed by XPS measurement, and a 5 Å thick oxygen-rich aluminum oxide layer is formed. This reduction occurs upon TMA exposure to as-received GaAs wafers.
Integration of Colour, Motion, Orientation, and Spatial Frequency in Visual Search
Authors: Poom Leo
Published: June 2009

Response times (RTs) in visual search were measured with either a single target specified by colour, motion, spatial frequency, or orientation alone, or specified by pairwise conjunctions of these features, or by presenting double targets, each specified by a separate feature. First, for all feature combinations, except for motion–colour, RTs were faster when double features were used to specify a single target than when they specified separate targets, implying location-specific redundancy gains predicted by coactivation on a common location-specific map. Second, coactivation, as revealed by race-model violations, occurred for all double-feature single-target conditions except the motion–colour and colour–orientation combinations. No violations occurred in double-target conditions. Taken together, these results are accounted for by well-known feature-specific sensitivities of cortical V1 cells and provide further evidence for a V1 locus of redundancy gain in visual search.
Are tests for predicting pre‐eclampsia good enough to make screening viable? A review of reviews and critical appraisal
Authors: CNOSSEN JELTSJE S. , RIET GERBEN TER , MOL BEN WILLEM , VAN DER POST JORIS A. , LEEFLANG MARISKA M. , MEADS CATHERINE A. , HYDE CHRIS , KHAN KHALID S.
Published: June 2009

The aim of this article is to review the accuracy of tests purported to be predictive of pre‐eclampsia, a major cause of maternal and perinatal mortality and morbidity worldwide. A review of systematic reviews was done. A total of 219 studies were evaluated for the accuracy of 27 tests for predicting pre‐eclampsia. Study quality assessment and data abstraction were performed using piloted proformas. Bivariate meta‐analyses were used to synthesize data. Levels of sensitivity and specificity were measured. There were deficiencies in many areas of methodology including blinding, test description, and reference standard adequacy. No test had a high level of both sensitivity and specificity of greater than 90%. Where multiple studies were available, only BMI > 34, alpha‐fetoprotein, fibronectin (cellular and total), and uterine artery Doppler (bilateral notching) measurements reached specificity above 90%. Only Doppler (any/unilateral notching, resistance index, and combinations) measurements were over 60% sensitive. Studies were of variable quality and most tests performed poorly. Further research should focus on tests which offer much higher levels of sensitivity than tests currently available. High sensitivity is a more useful attribute in early detection of pre‐eclampsia than specificity because consideration of benefits, harms and costs indicates a much greater preference for minimizing false negatives than false positives, although the ideal would be to avoid both.
Effectiveness of a multifaceted strategy to improve the appropriateness of cesarean sections
Authors: CALVO ANDRÉS , CAMPILLO CARLOS , JUAN MIGUEL , ROIG CATALINA , HERMOSO JUAN CARLOS , CABEZA PEDRO J.
Published: June 2009

The objective was to assess the effectiveness of a multifaceted strategy for improving the appropriateness of indications for cesarean sections in two public Spanish hospitals. A multifaceted strategy was used including the adoption of a consensus protocol with indications for emergency and prescheduled cesarean sections, continuing education and improvement, and the correction of deficiencies in organization. A pre and post‐intervention design was applied. The overall appropriateness rates for emergency cesarean sections increased from 68.3 to 84.3% in Son Llàtzer Hospital, and from 80.0 to 92.0% in the hospital in Menorca. The overall cesarean section rates at the end of the post‐intervention period decreased (not statistically significant) from 17.5 to 15.8% and from 29.0 to 22.0%, respectively. The multifaceted strategy applied seems to be effective in increasing the appropriateness of cesarean sections and possibly in decreasing the cesarean section rate.
Effects of country size and language similarity on international attitudes: A six‐nation study
Authors: van Oudenhoven Jan Pieter , Selenko Eva , Otten Sabine
Published: June 2009

Linguistically similar neighbouring nations that differ in size are often asymmetrical in their attitudinal relations towards each other: Citizens of smaller nations tend to see larger nations as less likeable and less similar than vice versa. We hypothesized that the smaller nations' reaction is the consequence of a threatened identity due to its relative size combined with too much similarity on a vital part of its identity, namely language. To test this hypothesis, 832 high‐school students from six different ethnic/national entities (France, Germany, Austria, the French‐ and German‐speaking parts of Switzerland, the French‐ and Dutch‐speaking parts of Belgium, and The Netherlands) completed a questionnaire on liking and similarity ratings. The results—to a large extent—showed that differences in size, in combination with linguistic similarity with another nation, pose a threat to the identity of the smaller nation or ethnic group. Differences in size, in combination with linguistic similarity, were associated with asymmetries in mutual liking on one hand and asymmetrical perceptions of similarity to the other country on the other hand. The conclusions of this study are consistent with findings of earlier research and stress the importance of language for a nation's identity. Moreover, the findings support social identity theory as a useful theory for understanding intergroup and international relations.
Book Reviews
Authors: Lamark Kathrine
Published: June 2009

Pocket Atlas of Radiographic Positioning, second edition. By T. B. Moeller & E. Reif. Translated from the fourth German edition into English. Stuttgart/New York: Thieme, 2009. ISBN: 978-3-13-107442-3. 378 pages. Price (paperback): NOK 544 / USD 39.95
Book Reviews
Authors: Hopp Einar
Published: June 2009

Imaging of the Temporal Bone. Fourth edition. Edited by J. D. Swartz & L. A. Loevner. New York: Thieme Medical Publishers, 2009. ISBN: 978-1-58890-345-7. 592 pages, 1506 illustrations. Price (hardback): USD 169.95
Following the fat trail to death
Authors: Williams Ruth
Published: June 2009

Monitoring the changing lipid composition of phagosome membranes reveals where these vesicles go and how they might get there.
Hyung Don Ryoo: A healthy career in cellular death
Authors: Williams Ruth
Published: June 2009

Ryoo engages the power of the fly to study apoptosis during development and disease.
Pygo2 expands mammary progenitor cells by facilitating histone H3 K4 methylation
Authors: Gu Bingnan , Sun Peng , Yuan Yuanyang , Moraes Ricardo C. , Li Aihua , Teng Andy , Agrawal Anshu , Rhéaume Catherine , Bilanchone Virginia , Veltmaat Jacqueline M. , Takemaru Ken-Ichi , Millar Sarah , Lee Eva Y.-H.P. , Lewis Michael T. , Li Boan , Dai Xing
Published: June 2009

Recent studies have unequivocally identified multipotent stem/progenitor cells in mammary glands, offering a tractable model system to unravel genetic and epigenetic regulation of epithelial stem/progenitor cell development and homeostasis. In this study, we show that Pygo2, a member of an evolutionarily conserved family of plant homeo domain–containing proteins, is expressed in embryonic and postnatal mammary progenitor cells. Pygo2 deficiency, which is achieved by complete or epithelia-specific gene ablation in mice, results in defective mammary morphogenesis and regeneration accompanied by severely compromised expansive self-renewal of epithelial progenitor cells. Pygo2 converges with Wnt/β-catenin signaling on progenitor cell regulation and cell cycle gene expression, and loss of epithelial Pygo2 completely rescues β-catenin–induced mammary outgrowth. We further describe a novel molecular function of Pygo2 that is required for mammary progenitor cell expansion, which is to facilitate K4 trimethylation of histone H3, both globally and at Wnt/β-catenin target loci, via direct binding to K4-methyl histone H3 and recruiting histone H3 K4 methyltransferase complexes.
The spectral photon flux of the radiometric calibration spectral source for the NIRSpec instrument of the James Webb Space Telescope
Authors: Taubert R D , Monte C , Baltruschat C , Schirmacher A , Gutschwager B , Hartmann J , Hollandt J , Kochems D , Küchel C , te Plate M
Published: June 2009

The radiometric calibration spectral source (RCSS) is a very low photon flux radiation source based on an integrating sphere, operated under vacuum and cryogenic conditions, for the testing and calibration of the near infrared multiobject dispersive spectrograph (NIRSpec). NIRSpec itself is a part of the scientific instrumentation of the James Webb Space Telescope. For the traceable calibration of the photon flux emitted by the RCSS in the wavelength range from 0.7 µm to 5 µm, dedicated calibration schemes were developed at PTB. To achieve this goal, the Spectral Radiance Comparator Facility and the Reduced Background Calibration Facility of the PTB have been significantly improved with respect to their detector instrumentation.
What's in the Literature?
Authors: Simmons Zachary
Published: June 2009

Peripheral neuropathies are among the most common disorders seen by neuromuscular specialists. Several of the articles in this issue's review focus on diagnosis, treatment, and prognosis of disorders of peripheral nerve, including some which address important issues relating to chronic inflammatory demyelinating polyneuropathy. Motor neuron diseases continue to be somewhat disproportionately represented, likely due to the devastating nature of amyotrophic lateral sclerosis. The TAR DNA-binding protein-43 (TDP-43) story as outlined in 2 of the articles is fascinating, particularly with regard to etiopathogenesis, whereas other articles focus on epidemiology, diagnosis, treatment, and symptom management, including some insights into Kennedy disease. Myotonic dystrophy and other muscle diseases are presented with some welcome news on treatment and management.
Framework for the Development of Response Protocols for Public Health Syndromic Surveillance Systems: Case Studies of 8 US States
Authors: Uscher-Pines Lori , Farrell Corey L. , Babin Steven M. , Cattani Jacqueline , Gaydos Charlotte A. , Hsieh Yu-Hsiang , Moskal Michael D. , Rothman Richard E.
Published: June 2009

Objectives:To describe current syndromic surveillance system response protocols in health departments from 8 diverse states in the United States and to develop a framework for health departments to use as a guide in initial design and/or enhancement of response protocols.

Methods:Case study design that incorporated in-depth interviews with health department staff, textual analysis of response plans, and a Delphi survey of syndromic surveillance response experts.

Results:All 8 states and 30 of the 33 eligible health departments agreed to participate (91% response rate). Fewer than half (48%) of surveyed health departments had a written response protocol, and health departments reported conducting in-depth investigations on fewer than 15% of syndromic surveillance alerts. A convened panel of experts identified 32 essential elements for inclusion in public health protocols for response to syndromic surveillance system alerts.

Conclusions:Because of the lack of guidance, limited resources for development of response protocols, and few examples of syndromic surveillance detecting previously unknown events of public health significance, health departments have not prioritized the development and refinement of response protocols. Systems alone, however, are not effective without an organized public health response. The framework proposed here can guide health departments in creating protocols that will be standardized, tested, and relevant given their goals with such systems. (Disaster Med Public Health Preparedness. 2009;3(Suppl 1):S29–S36)
Mathematical modelling of cilia-driven transport of biological fluids
Authors: Smith D. J. , Gaffney E. A. , Blake J. R.
Published: June 2009

Cilia-driven flow occurs in the airway surface liquid, in the female and male reproductive tracts and enables symmetry-breaking in the embryonic node. Viscoelastic rheology is found in healthy states in some systems, whereas in others may characterise disease, motivating the development of mathematical models that take this effect into account. We derive the fundamental solution for linear viscoelastic flow, which is subsequently used as a basis for slender-body theory. Our numerical algorithm allows efficient computation of three-dimensional time-dependent flow, bending moments, power and particle transport. We apply the model to the large-amplitude motion of a single cilium in a linear Maxwell liquid. A relatively short relaxation time of just 0.032 times the beat period significantly reduces forces, bending moments, power and particle transport, the last variable exhibiting exponential decay with relaxation time. A test particle is propelled approximately one-fifth as quickly along the direction of cilia beating for scaled relaxation time 0.032 as in the Newtonian case, and mean volume flow is abolished, emphasizing the sensitivity of cilia function to fluid rheology. These results may have implications for flow in the airways, where the transition from Newtonian to viscoelastic rheology in the peri-ciliary fluid may reduce clearance.
AMUC: Associated Motion capture User Categories
Authors: Norman Sally Jane , Lawson Sian E.M. , Olivier Patrick , Watson Paul , Chan Anita M.-A. , Dade-Robertson Martyn , Dunphy Paul , Green Dave , Hiden Hugo , Hook Jonathan , Jackson Daniel G.
Published: June 2009

The AMUC (Associated Motion capture User Categories) project consisted of building a prototype sketch retrieval client for exploring motion capture archives. High-dimensional datasets reflect the dynamic process of motion capture and comprise high-rate sampled data of a performer's joint angles; in response to multiple query criteria, these data can potentially yield different kinds of information. The AMUC prototype harnesses graphic input via an electronic tablet as a query mechanism, time and position signals obtained from the sketch being mapped to the properties of data streams stored in the motion capture repository. As well as proposing a pragmatic solution for exploring motion capture datasets, the project demonstrates the conceptual value of iterative prototyping in innovative interdisciplinary design. The AMUC team was composed of live performance practitioners and theorists conversant with a variety of movement techniques, bioengineers who recorded and processed motion data for integration into the retrieval tool, and computer scientists who designed and implemented the retrieval system and server architecture, scoped for Grid-based applications. Creative input on information system design and navigation, and digital image processing, underpinned implementation of the prototype, which has undergone preliminary trials with diverse users, allowing identification of rich potential development areas.
pH controls both transcription and post-translational processing of the protease BcACP1 in the phytopathogenic fungus Botrytis cinerea
Authors: Rolland Stéphane , Bruel Christophe , Rascle Christine , Girard Vincent , Billon-Grand Geneviève , Poussereau Nathalie
Published: June 2009

During pathogenesis, the ascomycete Botrytis cinerea secretes a range of cell-wall-degrading enzymes such as polygalacturonases, glucanases and proteases. We report the identification of a new member of the G1 family of proteases, BcACP1, which is secreted by B. cinerea during infection. The production of BcACP1 correlates with the acidification of the plant tissue, and transcriptional analysis of the Bcacp1 gene showed that it is only expressed under acidic growth conditions. Using a transcriptional reporter system, we showed that pH regulation of Bcacp1 is not mediated by the canonical PacC transcription factor binding site. Like other G1 proteases, BcACP1 is produced as a pro-enzyme. Trapping of the zymogen form allowed investigation of its maturation process. Evidence is presented for an autocatalytic proteolysis of the enzyme that is triggered by acidic pH. Environmental pH therefore controls Bcacp1 production at both the transcriptional and post-translational level.
Effect of FliK mutation on the transcriptional activity of the σ
54 sigma factor RpoN in Helicobacter pylori
Authors: Douillard Francois P. , Ryan Kieran A. , Hinds Jason , O'Toole Paul W.
Published: June 2009

Helicobacter pylori is a motile Gram-negative bacterium that colonizes and persists in the human gastric mucosa. The flagellum gene regulatory circuitry of H. pylori is unique in many aspects compared with the Salmonella/Escherichia coli paradigms, and some regulatory checkpoints remain unclear. FliK controls the hook length during flagellar assembly. Microarray analysis of a fliK-null mutant revealed increased transcription of genes under the control of the σ
54 sigma factor RpoN. This sigma factor has been shown to be responsible for transcription of the class II flagellar genes, including flgE and flaB. No genes higher in the flagellar hierarchy had altered expression, suggesting specific and localized FliK-dependent feedback on the RpoN regulon. FliK thus appears to be involved in three processes: hook-length control, export substrate specificity and control of RpoN transcriptional activity.
Polyunsaturated Fatty Acid and S-Adenosylmethionine Supplementation in Predementia Syndromes and Alzheimer's Disease: A Review
Authors: Panza Francesco , Frisardi Vincenza , Capurso Cristiano , D'Introno Alessia , Colacicco Anna M. , Di Palo Alessandra , Imbimbo Bruno P. , Vendemiale Gianluigi , Capurso Antonio , Solfrizzi Vincenzo
Published: June 2009

A growing body of evidence indicates that nutritional supplements can improve cognition; however, which supplements are effective remains controversial. In this review article, we focus on dietary supplementation suggested for predementia syndromes and Alzheimers disease (AD), with particular emphasis on S-adenosylmethionine (SAM) and polyunsaturated fatty acids (PUFA). Very recent findings confirmed that SAM can exert a direct effect on glutathione S-transferase (GST) activity. AD is accompanied by reduced GST activity, diminished SAM, and increased S-adenosylhomocysteine (SAH), the downstream metabolic product resulting from SAM-mediated transmethylation reactions, when deprived of folate. Therefore, these findings underscored the critical role of SAM in maintenance of neuronal health, suggesting a possible role of SAM as a neuroprotective dietary supplement for AD patients. In fact, very recent studies on early-stage AD patients and moderate- to late-stage AD patients were conducted with a nutriceutical supplementation that included SAM, with promising results. Given recent findings from randomized clinical trials (RCTs) in which n-3 PUFA supplementation was effective only in very mild AD subgroups or mild cognitive impairment (MCI), we suggest future intervention trials using measures of dietary supplementation (dietary n-3 PUFA and SAM plus B vitamin supplementation) to determine if such supplements will reduce the risk for cognitive decline in very mild AD and MCI. Therefore, key supplements are not necessarily working in isolation and the most profound impact, or in some cases the only impact, is noted very early in the course of AD, suggesting that nutriceutical supplements may bolster pharmacological approaches well past the window where supplements can work on their own. Recommendations regarding future research on the effects of SAM or n-3 PUFA supplementation on predementia syndromes and very mild AD include properly designed RCTs that are sufficiently powered and with an adequate length (e.g., 3–5 years of follow-up).
Whole-Mount In Situ Hybridization of Honeybee (Apis mellifera) Tissues
Authors: Dearden Peter K. , Duncan Elizabeth J. , Wilson Megan J.
Published: June 2009

INTRODUCTION

This protocol outlines how to perform in situ hybridization on honeybee embryos, adult brains, or ovaries to detect the expression pattern of a targeted transcript. The tissue is digested by proteinase K to promote probe penetration, and then prehybridized to block nonspecific binding of the probe.
SIRT Combines Homologous Recombination, Site-Specific Integration, and Bacterial Recombineering for Targeted Mutagenesis in Drosophila
Authors: Gao Guanjun , Wesolowska Natalia , Rong Yikang S.
Published: June 2009

INTRODUCTION

Systematic mutational analysis is required for the comprehensive deciphering of gene function. However, repeated targeting of a single locus is labor intensive and has not been a routine approach for studies using multicellular organisms. We have developed the “site-specific integrase mediated repeated targeting” (SIRT) method to facilitate targeted mutagenesis in Drosophila melanogaster. In SIRT, homologous recombination is used to place a landing site for the phage phiC31 integrase in the vicinity of the target locus. All subsequent genetic modifications to the same gene are introduced by integrase-mediated precise insertion of plasmids directly injected into embryos. For SIRT mutagenesis, one must generate a series of plasmid vectors that contain various DNA elements placed at different positions in the target-homologous clone. Unlike traditional cloning methods, SIRT is not limited by the availability of convenient restriction cut sites. This protocol presents the details of SIRT plasmid construction, relying heavily on the method of bacterial recombineering and using a number of streamlined DNA elements.
An Auxin Gradient and Maximum in theArabidopsisRoot Apex Shown by High-Resolution Cell-Specific Analysis of IAA Distribution and Synthesis
Authors: Petersson Sara V. , Johansson Annika I. , Kowalczyk Mariusz , Makoveychuk Alexander , Wang Jean Y. , Moritz Thomas , Grebe Markus , Benfey Philip N. , Sandberg Göran , Ljung Karin
Published: June 2009

Local concentration gradients of the plant growth regulator auxin (indole-3-acetic acid [IAA]) are thought to instruct the positioning of organ primordia and stem cell niches and to direct cell division, expansion, and differentiation. High-resolution measurements of endogenous IAA concentrations in support of the gradient hypothesis are required to substantiate this hypothesis. Here, we introduce fluorescence-activated cell sorting of green fluorescent protein–marked cell types combined with highly sensitive mass spectrometry methods as a novel means for analyses of IAA distribution and metabolism at cellular resolution. Our results reveal the presence of IAA concentration gradients within the Arabidopsis thaliana root tip with a distinct maximum in the organizing quiescent center of the root apex. We also demonstrate that the root apex provides an important source of IAA and that cells of all types display a high synthesis capacity, suggesting a substantial contribution of local biosynthesis to auxin homeostasis in the root tip. Our results indicate that local biosynthesis and polar transport combine to produce auxin gradients and maxima in the root tip.
Therapeutic antitumor efficacy of monoclonal antibody against Claudin‐4 for pancreatic and ovarian cancers
Authors: Suzuki Masayo , Kato‐Nakano Mariko , Kawamoto Shinobu , Furuya Akiko , Abe Yuzuru , Misaka Hirofumi , Kimoto Naoya , Nakamura Kazuyasu , Ohta So , Ando Hiroshi
Published: June 2009

Claudin‐4 (CLDN4) is a tetraspanin transmembrane protein of tight junction structure and is highly expressed in pancreatic and ovarian cancers. In this study, we aimed to generate an anti‐Claudin‐4 monoclonal antibody (mAb) and evaluate its antitumor efficacy in vitro and in vivo. To isolate specific mAb, we generated CLDN3, 4, 5, 6, and 9, expressing Chinese hamster ovary (CHO) cells, and then used them as positive and negative targets through cell‐based screening. As a result, we succeeded in isolating KM3900 (IgG2a), which specifically bound to CLDN4, from BXSB mice immunized with pancreatic cancer cells. Immunoprecipitation and flow cytometry analysis revealed that KM3900 recognized the conformational structure and bound to extracellular loop 2 of CLDN4. Furthermore, binding of KM3900 was detected on CLDN4‐expressing pancreatic and ovarian cancer cells, but not on negative cells. Next, we made the mouse–human chimeric IgG1 (KM3934) and evaluated its antitumor efficacy. KM3934 induced dose‐dependent antibody‐dependent cellular cytotoxicity and complement‐dependent cytotoxicity in vitro, and significantly inhibited tumor growth in MCAS or CFPAC‐1 xenograft SCID mice in vivo (P < 0.05). These results suggest that mAb therapy against CLDN4 is promising for pancreatic and ovarian cancers. (Cancer Sci 2009; 100: 1623–1630)
A non‐synonymous mutation in a conserved site of the MTTP gene is strongly associated with protein activity and fatty acid profile in pigs
Authors: Estellé J. , Fernández A. I. , Pérez‐Enciso M. , Fernández A. , Rodríguez C. , Sánchez A. , Noguera J. L. , Folch J. M.
Published: June 2009

Despite the economic interest of the fatty acid profile in pigs, no gene has been convincingly associated with this trait so far. Here, the porcine microsomal triglyceride transfer protein (MTTP) gene, which plays a crucial role in the assembly of nascent lipoproteins, has been analysed as a positional candidate gene for a QTL affecting the fatty acid composition that was previously identified on chromosome 8 in an Iberian by Landrace F2 cross. By resequencing a panel of different breeds, a non‐synonymous polymorphism in a conserved residue of the lipid transfer domain of MTTP was identified. Association analyses with this polymorphism showed a strong association with the fatty acid composition of porcine fat, much stronger than the QTL effect, in the F2 cross and in a synthetic Sino‐European line. In addition, in vitro activity assays in liver protein extracts have shown that this mutation is also associated with the lipid transfer activity of the MTTP protein (P < 0.1). These results suggest that the detected polymorphism is a potential causal factor of the fatty acid composition QTL. There appears to be an interaction between the porcine MTTP genotype and the type of fat source in the pig diet, which would agree with the previous results on the biology of MTTP biology.
Plumage colour mutations and melanins in the feathers of the Japanese quail: a first comparison
Authors: Minvielle F. , Cecchi T. , Passamonti P. , Gourichon D. , Renieri C.
Published: June 2009

The absorbance of melanin content from dorsal feathers was compared between wild‐type Japanese quail and nine other quail plumage colours determined by single mutations in one of seven genes: extended brown (MC1R), yellow (ASIP), silver (MITF), lavender (MLPH), roux (TYRP1), imperfect albinism (SLC45A2) and rusty. As compared with wild‐type quail, all mutations but extended brown decreased total melanins. The largest decrease was observed in quail with one of the dilution mutations at TYRP1, MLPH or SLCA45A2. No difference in eumelanins was found between the 10 plumage colours. Despite visible colour differences, homozygous and heterozygous mutants at MITF, or the two imperfect albino (white) and cinnamon (pale yellow) alleles at SLC45A2, could not be differentiated on the basis of melanins. In contrast, the two white phenotypes caused by mutations at MITF and SLC45A2, or the two reddish plumage colours caused by the roux and rusty non‐allelic mutations had different total melanin contents. The results showed that rusty was not likely to be a dilution mutation.
Jurassic synorogenic basin filling in western Korea: sedimentary response to inception of the western Circum‐Pacific orogeny
Authors: Egawa Kosuke , Lee Yong Il
Published: June 2009

This is the first sedimentologic and stratigraphic attempt to demonstrate Jurassic subduction‐induced basin‐filling processes in the early stage of the western Circum‐Pacific orogeny. The Chungnam Basin in western Korea was filled with a Lower to Middle Jurassic nonmarine succession, the Nampo Group, whose deposition postdated the Triassic final assembly of Chinese continental blocks. The Nampo Group consists of two repeated, fining‐ to coarsening‐upward alluvio‐lacustrine sequences, separated by an interval of thick breccia–gravel progradation deposits and its related strong proximal unconformities. No temporal variation in the degree of chemical weathering, along with the predominance of coals and a tropic to subtropic paleoflora, reveals little or no climate fluctuations during deposition of the Nampo Group. The observed relationships provide a record of sedimentation most likely controlled by temporal variations of tectonically driven sediment flux. Such syntectonic sedimentation of the Chungnam Basin occurred at a convergent margin of continental‐arc setting during the Daebo orogeny, synchronous with the early subduction of the western paleo‐Pacific ocean that resulted in formation of an accretionary complex along the East Asian continental margin during Jurassic time. Hence, synorogenic deposition in the Chungnam Basin is interpreted as sedimentary response to subduction–accretion of the western paleo‐Pacific plate.
Clinical significance of minimal residual disease at day 15 and at the end of therapy in childhood acute lymphoblastic leukaemia
Authors: Sutton Rosemary , Venn Nicola C. , Tolisano Jonathan , Bahar Anita Y. , Giles Jodie E. , Ashton Lesley J. , Teague Lochie , Rigutto Gemma , Waters Keith , Marshall Glenn M. , Haber Michelle , Norris Murray D. ,   Australian and New Zealand Children’s Oncology Group
Published: June 2009

Detection of minimal residual disease (MRD) after induction and consolidation therapy is highly predictive of outcome for childhood acute lymphoblastic leukaemia (ALL) and is used to identify patients at high risk of relapse in several current clinical trials. To evaluate the prognostic significance of MRD at other treatment phases, MRD was measured by real‐time quantitative polymerase chain reaction on a selected group of 108 patients enrolled on the Australian and New Zealand Children’s Cancer Study Group Study VII including 36 patients with a bone marrow or central nervous system relapse and 72 matched patients in first remission. MRD was prognostic of outcome at all five treatment phases tested: at day 15 (MRD ≥ 5 × 10−2, log rank P < 0·0001), day 35 (≥1 × 10−2, P = 0·0001), 4 months (≥5 × 10−4, P < 0·0001), 12 months (MRD ≥ 1 × 10−4, P = 0·006) and 24 months (MRD ≥ 1 × 10−4, P < 0·0001). Day 15 was the best early MRD time‐point to differentiate between patients with high, intermediate and low risk of relapse. MRD testing at 12 and particularly at 24 months, detected molecular relapses in some patients up to 6 months before clinical relapse. This raised the question of whether a strategy of late monitoring and salvage therapy will improve outcome.
Natural polyphenols antagonize the antimyeloma activity of proteasome inhibitor bortezomib by direct chemical interaction
Authors: Kim Tae Young , Park Jongmin , Oh Bora , Min Hyun Jung , Jeong Tae‐Sook , Lee Jae Hoon , Suh Cheolwon , Cheong June‐Won , Kim Hyo Jung , Yoon Sung‐Soo , Park Seung Bum , Lee Dong Soon ,   the Korean Multiple Myeloma Working Party (KMMWP)
Published: June 2009

Bortezomib is a therapeutic proteasome inhibitor with antimyeloma activity and polyphenols are well known compounds that exert antiproliferative effects against tumuors. We attempted to co‐treat myeloma cells with bortezomib and polyphenols, anticipating a synergistic effect. However, the anticancer activity of bortezomib was blocked by the polyphenols. The structural features of the polyphenols correlated strikingly with their antagonistic effect; in particular, the presence or absence of a vicinal diol moiety was the key element for effective blockage of the anticancer function of bortezomib. We speculated that the vicinal diols in the polyphenols interact with the boronic acid of bortezomib and convert the active triangular boronic acid of bortezomib to an inactive tetrahedral boronate, thus abolishing the antimyeloma activity of bortezomib. We confirmed this hypothesis by 11B nuclear magnetic resonance spectroscopy and an in vitro assay on multiple myeloma (MM) cell lines and primary myeloma cells from patients. Based on these findings, restriction of the intake of natural polyphenols in foods or vitamin supplements during bortezomib treatment in MM patients should be considered.
Aggression in imported fire ants: an explanation for shifts in their spatial distributions in Southern United States?
Authors: FADAMIRO HENRY Y. , HE XIAOFANG , CHEN LI
Published: June 2009

Abstract 1. The imported fire ants, Solenopsis invicta Buren (red), S. richteri Forel (black), and their hybrids (S. invicta × S. richteri) are sympatric congeners with overlapping but shifting spatial distributions in northern Alabama and Mississippi, United States.

2. The abilities of workers of the three ant forms (or species) to recognise non‐nestmate conspecifics and heterospecifics were compared in separate aggression bioassays using three group sizes of competitor numbers (battles): 1‐1, 5‐1, and 5‐5 resident–intruder battles.

3. Workers of all three forms showed significant aggression toward non‐nestmate conspecifics and heterospecifics. The results of the intra‐specific aggression bioassays showed that S. invicta had the lowest aggression threshold, whereas S. richteri was the least aggressive. Survival rates 1 day after intra‐specific encounters were higher for S. richteri than for S. invicta or hybrids, consistent with its lower aggressiveness.

4. In inter‐specific interactions, S. invicta workers showed the greatest aggression and were more aggressive towards S. richteri than to hybrids. Furthermore, survival 1 day after inter‐specific encounters was highest for S. invicta workers, whether they were the intruders or residents. The hybrid form was intermediate between both parental forms in aggression and post‐aggression survival.

5. The live 1‐1 and 5‐5 battles produced similar and consistent results, but differences were amplified in the 5‐5 battles, suggesting an effect of group size on aggression. These results may explain the observed shifts in the spatial distributions of the three forms and range restriction of S. richteri in southern United States.
Metabolic diseases and associated complications: sex and gender matter!
Authors: Kautzky‐Willer A. , Handisurya A.
Published: June 2009

Background  Clinicians and health professionals are increasingly challenged to understand and consider the different health needs of women and men. The increase of gender awareness and the expanding science of gender medicine will affect more and more clinical practice. This review addresses gender‐specific aspects in metabolic disorders and related complications, which represent an increasing burden of this century and a great challenge to public health.

Design  There is increasing evidence of gender‐related differences in risk factors, clinical manifestation and sequelae of obesity and diabetes and increasing knowledge that prevention, detection and therapy of illness affect men and women differently.

Results  Some gender‐specific aspects, especially regarding cardiovascular disease, have been studied in more detail, but for many complications sex‐related analyses of the results of both clinical trials and basic science are still missing or disregarded. Impaired glucose and lipid metabolism as well as dysregulation of energy balance and body fat distribution have a great impact on overall health via neuroendocrine changes and inflammatory pathways and deteriorate the course of many diseases with particular harm for women. Metabolic diseases dramatically affect life of men and women from infancy up to old age and are a major challenge for women during pregnancy. Great impact is attached to the intrauterine period and the lifelong implications of fetal programming.

Conclusions  Initiation of prospective studies on the impact of gender as primary outcome and investigation of gender‐related pathophysiological mechanisms of chronic diseases will help to improve patient care and to implement evidence‐based gender‐specific prevention programs and clinical recommendations in future.