bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a novel amplicon at distal 17q containing the BIRC5/SURVIVIN gene in malignant peripheral nerve sheath tumours
Authors: Storlazzi CT , Brekke HR , Mandahl N , Brosjö O , Smeland S , Lothe RA , Mertens F
Published: May 2006

Previous studies have suggested that amplification of genes, notably the TOP2A gene, on chromosome arm 17q may be important for the development of malignant peripheral nerve sheath tumour (MPNST). In order to study the frequency, distribution, and chromosomal organization of rearrangements at 17q, interphase and metaphase fluorescence in situ hybridization (FISH) were used to evaluate copy number changes at 17q in 28 MPNSTs. Increased copy numbers were seen for the ERBB2 and TOP2A genes in eight and nine cases, respectively, supporting a potential role for these two genes in MPNST tumourigenesis. Net gain of distal 17q material was observed in 16 of the 28 MPNSTs, with high‐level gain in three cases, and was associated with poor outcome. Among the 26 patients for whom follow‐up data were available, gain of distal 17q was present in 11 of 12 tumours that had metastasized, compared with 4 of 14 of those that had not metastasized. Detailed FISH mapping analysis of metaphase spreads identified a 2 Mb commonly gained/amplified region at 17q25. Among the genes mapping to this region, BIRC5, which encodes the baculoviral IAP repeat‐containing protein 5/survivin protein, is a strong candidate target gene for amplification, as it has been previously shown to be overexpressed in neurofibromatosis type 1‐associated MPNST. Three other genes that co‐amplified with BIRC5 represent other potential candidate genes: PTDSR involved in apoptosis; SEPT9 overexpressed in human malignant brain tumours; and SOCS3 involved in cell survival and differentiation of neurons. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Isolation and characterisation of selected germander diterpenoids from authenticated Teucrium chamaedrys and T. canadense by HPLC, HPLC‐MS and NMR
Authors: Sundaresan P. Ramnathan , Slavoff Sarah A. , Grundel Erich , White Kevin D. , Mazzola Eugene , Koblenz Daniel , Rader Jeanne I.
Published: May 2006

Teucrium species, such as germander, are rich in neo‐clerodane diterpenoids and have been used in traditional folk medicine for their stimulant, diuretic, antipyretic and antiseptic properties. However, the furano neo‐clerodane diterpenoids present in germander have been implicated in the in vivo hepatotoxicity of this botanical. In this study, authenticated germander (Teucrium chamaedrys L. and Teucrium canadense L.) was used as the source material. Methanol extracts of powdered plant material were prepared and analysed by HPLC using Synergi® Max‐RP columns with monitoring at 220 nm. Limited amounts of teucrin A and other diterpenoid standards were analysed on a Synergi Max‐RP column in order to determine their retention times and to generate calibration curves. The same standards were subjected to concurrent mass spectral analysis. Teucrin A and diterpenoids such as dihydroteugin, teuflin, teuflidin and teucvidin were tentatively identified in the plant extracts by HPLC‐MS and 1H‐NMR experiments. For the isolation of teucrium diterpenoids on a semipreparative scale, a solid‐phase extraction method was developed for the first time using styrene divinylbenzene and strata‐X sorbents for teucrin A and teuflin, respectively. Semi‐preparative HPLC of the methanol extract of the powdered aerial parts of Teucrium plants was carried out on a semipreparative Synergi Max‐RP column with photodiode array detection in order to confirm the identities of some diterpenoids by HPLC‐MS and NMR. Copyright © 2006 John Wiley & Sons, Ltd.
Novel polymerizable N‐aromatic maleimides as free radical initiators for photopolymerization
Authors: Wang Hongyu , Wei Jun , Jiang Xuesong , Yin Jie
Published: May 2006

Four kinds of polymerizable N‐aromatic maleimides (MIs)—4‐[(4‐maleimido)phenoxy]benzophenone (MPBP), 4,4′‐bis[(4‐maleimido)phenoxy]benzophenone (BMPBP), 4‐maleimidobenzophenone (MBP), and 4,4′‐bismaleimidobenzophenone (BMBP)—were synthesized as free radical photoinitiators, by introducing directly N‐phenylmaleimide groups or maleimide groups into the molecule of benzophenone (BP). Compared with BP, their UV‐visible spectra have a significantly red‐shifted maximum absorption. The maximum absorption of MIs containing bifunctional maleimide groups is slightly larger than the corresponding monofunctional ones. Choosing an unsaturated tertiary amine N,N‐dimethylaminoethyl methacrylate (DMAEMA) as coinitiator, the photopolymerization of 1,6‐hexanediol diacrylate (HDDA), initiated by these four MIs, was studied through photo‐DSC. The results show that all the MIs are dramatically more efficient than BP. Among them, MPBP is the most efficient, in which the polymerization rate is almost three times as high as that of the BP system. Photoinitiators containing bifunctional maleimide groups, though having higher final conversion, are less efficient than the corresponding monofunctional ones. These polymerizable photoredox systems significantly reduced the migration of the active species, leading to their higher efficiency. Copyright © 2006 Society of Chemical Industry
Synthesis and thermal cure of diphenyl ethers terminated with acetylene and phenylacetylene
Authors: Wang Fan , Xu Jinfeng , Zhang Jian , Huang Farong , Shen Yongjia , Du Lei
Published: May 2006

Two kinds of novel compounds, diphenylacetylene diphenyl ether (DPADPE) and diacetylene diphenyl ether (DADPE), were prepared and polymerized under heating. Raman, DSC and 13C CP/MAS NMR analyses were used for studying the polymerization reaction. DPADPE and DADPE have melting points at 190 and 79 °C, with exothermic peaks of the DSC curves at 375 and 215 °C for curing, respectively. Raman and 13C CP/MAS NMR spectra show that DPADPE could be cured at a temperature higher than 300 °C and DADPE at a lower temperature of higher than 150 °C. The kinetic parameters for the thermal crosslinking reactions were obtained by the Ozawa method and the results show that the apparent activation energy is 152 kJ mol−1 for DPADPE and 109 kJ mol−1 for DADPE. An ene–yne Straus product appears in the cured DADPE, whereas this product has not been identified in the cured DPADPE. The cured DPADPE and DADPE demonstrate good thermal and thermo‐oxidative stability. Copyright © 2006 Society of Chemical Industry
Continuous reaction system to investigate the dispersion polymerization of vinyl monomers in supercritical carbon dioxide
Authors: Giaconia Alberto , Filardo Giuseppe , Scialdone Onofrio , Galia Alessandro
Published: May 2006

A laboratory‐scale continuous reaction system using a stirred tank reactor was assembled in our laboratory to study the dispersion polymerization of vinyl monomers in supercritical carbon dioxide (scCO2). The apparatus was equipped with a suitable downstream separation section to collect solid particles entrained in the effluent stream from the reactor, whose monomer concentration could be measured online with a gas chromatograph. The dispersion polymerization of methyl methacrylate in scCO2 was selected as a model process to be investigated in the apparatus. The experiments were performed at 65 °C and 25 MPa with 2,2′‐azobisisobutyronitrile as the initiator and a reactive polysiloxane macromonomer as a surfactant to investigate the effect of the mean residence time of the reaction mixture on the monomer conversion, polymerization rate, polymer molecular weight, and particle size distribution. The results were compared with those obtained in batch polymerizations carried out under similar operative conditions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4122–4135, 2006
Molecular size and conformational effects on oligophenylene's electronic and vibrational properties
Authors: Ivanović N. , Radisavljević I. , Marjanović D. , Bojanić S. , Carreras C.
Published: May 2006

Electronic and vibrational properties of phenylene‐based oligomers from biphenyl P2P to para‐sexiphenil P6P, and their dependence on torsion angle are calculated using semiempirical quantum mechanic (AM1, ZINDO/S) and ab initio linear combination of atomic orbitals methods. The systematic relations between molecular size and geometry, and numerous molecular properties have been established, providing the basis both for the spectroscopic identification of different structures that could appear during material processing and for tailoring of devices with desired properties. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1783–1794, 2006
Atomistic packing models for experimentally investigated swelling states induced by CO2 in glassy polysulfone and poly(ether sulfone)
Authors: Heuchel Matthias , Böhning Martin , Hölck Ole , Siegert Martin R. , Hofmann Dieter
Published: May 2006

Atomistic packing models have been created, which help to better understand the experimentally observed swelling behavior of glassy polysulfone and poly (ether sulfone), under CO2 gas pressures up to 50 bar at 308 K. The experimental characterization includes the measurement of the time‐dependent volume dilation of the polymer samples after a pressure step and the determination of the corresponding gas concentrations by gravimetric gas‐sorption measurements. The models obtained by force‐field‐based molecular mechanics and molecular dynamics methods allow a detailed atomistic analysis of representative swelling states of polymer/gas systems, with respect to the dilation of the matrix. Also, changes of free volume distribution and backbone mobility are accessible. The behavior of gas molecules in unswollen and swollen polymer matrices is characterized in terms of sorption, diffusion, and plasticization. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1874–1897, 2006
Captan and fenitrothion dissipation in field‐treated cauliflowers and effect of household processing
Authors: Fernández‐Cruz María L , Barreda Mercedes , Villarroya Mercedes , Peruga Arantzazu , Llanos Susana , García‐Baudín José M
Published: May 2006

Field trial studies have been performed with captan and fenitrothion on cauliflower to propose maximum residue limits and to study the dissipation of the pesticides. Residue levels have been determined at different times following good laboratory practice using gas chromatography with mass spectrometric detection. The behaviour of residue levels of these compounds after household processing has been analysed using gas chromatography with electron capture detection. Seven days after treatment, residue levels of captan could be detected, but not of fenitrothion. The half‐lives of dissipation for captan and fenitrothion were calculated as 0.9 and 1.8 days respectively. Washing did not significantly affect the residual amounts of captan and fenitrothion observed in raw vegetables; however, after cooking, captan had degraded completely, whereas residue levels of fenitrothion were not modified significantly. Copyright © 2006 Society of Chemical Industry
Cuticular uptake of xenobiotics into living plants. part 2: influence of the xenobiotic dose on the uptake of bentazone, epoxiconazole and pyraclostrobin, applied in the presence of various surfactants, into Chenopodium album, Sinapis alba and Triticum aestivum leaves
Authors: Forster W Alison , Zabkiewicz Jerzy A , Liu Zhiqian
Published: May 2006

This study has determined the uptake of three pesticides, applied as commercial or model formulations in the presence of a wide range of surfactants, into the leaves of three plant species (bentazone into Chenopodium album L. and Sinapis alba L., epoxiconazole and pyraclostrobin into Triticum aestivum L.). The results have confirmed previous findings that the initial dose (nmol mm−2) of xenobiotic applied to plant foliage is a strong, positive determinant of uptake. This held true for all the pesticide formulations studied, although surfactant concentration was found to have an effect. The lower surfactant concentrations studied showed an inferior relationship between the amount of xenobiotic applied and uptake. High molecular mass surfactants also produced much lower uptake than expected from the dose uptake equations in specific situations. Copyright © 2006 Society of Chemical Industry
Cuscore Statistics to Monitor a Non‐stationary System
Authors: Nembhard Harriet Black , Valverde‐Ventura René
Published: May 2006

We investigate the monitoring of a process subject to minimum mean‐squared error feedback control using cumulative score (Cuscore) charts. Specifically, we design Cuscore statistics to discover spike, step, bump, and ramp signals hidden in non‐stationary disturbance for feedback‐controlled processes. We develop the adjustment and monitoring policies for combinations of process dynamics, disturbance, and signal that are practical in industry. We also address issues of detection probabilities and distributions using simulation. A manufacturing case study is used to illustrate the utility of the Cuscore approach. Copyright © 2006 John Wiley & Sons, Ltd.
Towards a science of systems
Authors: Troncale Len
Published: May 2006

Three unique and still timely aspects of Miller's text Living Systems were his citation of 173 specific ‘cross‐level’ hypotheses, his unification of a vast number of phenomena from the biomedical sciences to the social sciences using a consistent taxonomy of seven hierarchical levels and 20 subsystems, and his consistent effort to make systems hypotheses more testable. This article describes and discusses 20 similarities and dissimilarities between ‘cross‐level hypotheses’ and the transdisciplinary ‘linkage propositions’ between 100 systems processes used in an alternative ‘system of system's processes’. It contrasts Miller's use of 20 ‘critical subsystems’ versus use of these 100 ‘systems isomorphies’ as the basis for classification and application of systems knowledge. It also presents analysis of empirical data published in peer‐reviewed natural science journals to ‘test’ the validity of Miller's hierarchical levels with some unexpected preliminary results. It relates Miller's biomedically‐based vision of ‘measurable systems parameters’ to the tenets of the new field of Systems Pathology. The paper concludes with an evaluation of Miller's contributions in terms of recent developments in the natural sciences, systems science and the newer complex systems movement. Copyright © 2006 John Wiley & Sons, Ltd.
Lehrter Bahnhof Berlin: Die Haupteingangsfassaden
Authors: Gugeler Jochen , Gerber Hannes , Schneider Jens , Havemann Kathrin
Published: May 2006

Die Bahnhofshalle des neuen Berliner Hauptbahnhofes betritt man von Norden oder Süden durch zwei außergewöhnliche Glasfassaden. Das Tragwerk der Haupteingangsfassaden besteht ausschließlich aus Seilen und Glas. Wie die Stabschale des Nord‐Süd‐Daches weisen sie zahlreiche Sonderkonstruktionen auf, die alle Beteiligten vor schwierige Aufgaben stellten. Neben dem besonderen Tragsystem der vertikalen Seilbinder sind hier vor allem die Glasschwerter zu nennen, die gewaltige Lasten zu ertragen haben. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Klimabelastung und Lastverteilung bei Mehrscheiben‐Isolierglas
Authors: Feldmeier Franz
Published: May 2006

Eine Änderung der Temperatur oder des barometrischen Drucks erzeugt eine Druckdifferenz zwischen den Scheibenzwischenräumen einer Isolierglasscheibe und dem Außenraum und führt zu einer Belastung der Einzelscheiben. Andererseits werden externe auf eine Einzelscheibe einwirkende Lasten von den Scheiben gemeinsam getragen. Im allgemeinen hängt das Verhalten der Scheiben von der Steifigkeit des Systems ab. Übliche rechteckige Isolierglasscheiben normaler Größe zeigen die erwartete Lastverteilung und nur geringe Klimalasten. Kleine Formate mit dicken Glasscheiben, Dreifach‐Isolierglas, Dreiecke und punktgestützte Scheiben sowie gebogene Scheiben tragen eine deutlich höhere Last. Glasbruch und Schäden am Randverbund können die Folge sein. Die technischen Grundlagen werden beschrieben und die Theorie in einer allgemeinen Form formatunabhängig für unterschiedliche Lasttypen entwickelt. Zur praktischen Anwendung werden die Gleichungen in einer linearisierten Form dargestellt und auf die üblichen Konstruktionen Zweischeiben‐ und Dreischeiben‐Isolierglas mit symmetrischem Aufbau angewandt. Die Definition des isochoren Druckes und des Isolierglasfaktors erlauben Verformung und Spannung in der üblichen Weise zu berechnen. In einem Beispiel wird die Berechnung der Lastverteilung und der klimatischen Belastung schrittweise durchgeführt und das Ergebnis dargestellt. Die Gleichungen und die erforderlichen Koeffizienten sind in einem Anhang zusammengestellt. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Kleben im Bauwesen – gestern, heute, morgen – Allgemeine Übersicht und Ausblick auf die Forschung im Konstruktiven Glasbau an der Fachhochschule München (FHM)
Authors: Bucak Ömer , Hagl Anneliese
Published: May 2006

Kleben im Bauwesen hat eine lange Tradition. Die Geschichte des Klebens beginnt spätestens mit der Entwicklung des Mörtels im vorchristlichen Rom. Seither hat die Anwendung dieser Technologie bedeutende Fortschritte erzielt – und auch Rückfälle erlitten. Heute klebt der moderne Bauingenieur in vielen Bereichen des Bauens, ohne daß ihm meist bewußt ist, daß er die Fügetechnik “Kleben” anwendet. Dieser Bericht soll zum einen eine allgemeine Übersicht über die im Bauwesen üblichen “Klebstoffe” geben, zum anderen soll insbesondere die Technik des Klebens im Glasbau beleuchtet werden. An der Frage nach den Eigenschaften der Klebstoffe für den Glasbau soll aufgezeigt werden, welche Aspekte bei der Erforschung dieser neuen Verbindungstechnologie bedacht werden müssen. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐Newtonian flow in a thin film with boundary conditions of Coulomb's type
Authors: Saidi F.
Published: May 2006

This paper concerns the asymptotic behavior of solutions of the three‐dimensional non‐Newtonian fluid flow with slip condition of Coulomb's type imposed on a part of the boundary domain. Existence and uniqueness results for the weak solution are proved. We study the limit when the thickness tends to zero and we prove a convergence theorem for velocity and pressure in appropriate functional spaces. The limit of slip condition is obtained. Besides, the uniqueness of the velocity and the pressure limits are also proved.
Correlation between serial measurements of N‐terminal pro brain natriuretic peptide and ambulatory cardiac filling pressures in outpatients with chronic heart failure
Authors: Braunschweig Frieder , Fahrleitner‐Pammer Astrid , Mangiavacchi Maurizio , Ghio Stefano , Fotuhi Parwis , Hoppe Uta C. , Linde Cecilia
Published: May 2006

Background

Serial measurements of N‐terminal pro brain natriuretic peptide (NT‐proBNP) have been suggested for the management of outpatients with chronic heart failure (CHF). The relationship between NT‐proBNP plasma levels and central haemodynamic parameters in this setting is not known.

Methods

In 19 outpatients with CHF, NT‐proBNP was related to central haemodynamic information, continuously measured with an implanted haemodynamic monitor (IHM) during 24 h of daily living activities (“24 h”) and during supine rest (“rest”). In 13 patients, three to seven serial measurements were obtained with a mean time interval of 39 days (range 19–113).

Results

At the first visit (n=19), NT‐proBNP plasma levels were dispersed over a wide range of filling pressures and not correlated with the 24 h median of the right ventricular systolic pressure (RVSP) and the estimated pulmonary artery pressure (ePAD). However, in the individual patient, serial measurements yielded significant positive correlations between NT‐proBNP and RVSP (p=0.006) and ePAD (p=0.001). During “24 h” compared with “rest”, the median RVSP and ePAD were elevated by 20±16% and 32±18%, respectively, and corresponded better with NT‐proBNP (p<0.05).

Conclusion

In outpatients with CHF, single measurements of NT‐proBNP are not correlated with cardiac filling pressures. However, serial measurements of NT‐proBNP in each individual patient show a significant positive correlation with central haemodynamic parameters and reflect changes in the haemodynamic state over time.
Elevated circulating levels of heat shock protein 70 are related to systemic inflammatory reaction through monocyte Toll signal in patients with heart failure after acute myocardial infarction
Authors: Satoh Mamoru , Shimoda Yudai , Akatsu Tomonari , Ishikawa Yuh , Minami Yoshitaka , Nakamura Motoyuki
Published: May 2006

Background

Recent studies have shown that heat shock protein (HSP) 70 may serve as a “damage signal” to the immune system and could be the endogenous ligand for Toll‐like receptor (TLR) 4 mediating synthesis of inflammatory cytokines.

Aims

To explore the relationship between circulating HSP70 levels and activation of monocyte TLR4 and myocardial damage after AMI.

Methods and results

This study examined circulating HSP70 and monocyte TLR4 levels in 52 patients with AMI and 20 controls, and analyzed ex vivo inflammatory cytokine productions using HSP70‐stimulated monocytes. Circulating HSP70 levels were higher in AMI patients on day 1 after onset than in controls and remained elevated in AMI patients 14 days after onset. HSP70 levels were positively correlated with monocyte TLR4, plasma interleukin‐6 and tumor necrosis factor‐α levels in AMI patients. HSP70 levels 14 days after onset were higher in AMI patients with heart failure (n=15) than in those without heart failure. In our in vitro study, HSP70‐stimulated monocytes resulted in dose‐dependent TLR4 expression and release of inflammatory cytokines. TLR4 antibody inhibited inflammatory cytokines release.

Conclusions

Elevated circulating levels of HSP70 may be involved in TLR4 signal‐mediated immune response and the progression of heart failure after AMI.
Truncated tau from sporadic Alzheimer's disease suffices to drive neurofibrillary degeneration in vivo
Authors: Zilka Norbert , Filipcik Peter , Koson Peter , Fialova Lubica , Skrabana Rostislav , Zilkova Monika , Rolkova Gabriela , Kontsekova Eva , Novak Michal
Published: May 2006

Truncated tau protein is the characteristic feature of human sporadic Alzheimer's disease. We have identified truncated tau proteins conformationally different from normal healthy tau. Subpopulations of these structurally different tau species promoted abnormal microtubule assembly in vitro suggesting toxic gain of function. To validate pathological activity in vivo we expressed active form of human truncated tau protein as transgene, in the rat brain. Its neuronal expression led to the development of the neurofibrillary degeneration of Alzheimer's type. Furthermore, biochemical analysis of neurofibrillary changes revealed that massive sarcosyl insoluble tau complexes consisted of human Alzheimer's tau and endogenous rat tau in ratio 1:1 including characteristic Alzheimer's disease (AD)‐specific proteins (A68). This work represents first insight into the possible causative role of truncated tau in AD neurofibrillary degeneration in vivo.
Inferring biomolecular regulatory networks from phase portraits of time‐series expression profiles
Authors: Cho Kwang-Hyun , Kim Jeong-Rae , Baek Songjoon , Choi Hyung-Seok , Choo Sang-Mok
Published: May 2006

Reverse engineering of biomolecular regulatory networks such as gene regulatory networks, protein interaction networks, and metabolic networks has received an increasing attention as more high‐throughput time‐series measurements become available. In spite of various approaches developed from this motivation, it still remains as a challenging subject to develop a new reverse engineering scheme that can effectively uncover the functional interaction structure of a biomolecular network from given time‐series expression profiles (TSEPs). We propose a new reverse engineering scheme that makes use of phase portraits constructed by projection of every two TSEPs into respective phase planes. We introduce two measures of a slope index (SI) and a winding index (WI) to quantify the interaction properties embedded in the phase portrait. Based on the SI and WI, we can reconstruct the functional interaction network in a very efficient and systematic way with better inference results compared to previous approaches. By using the SI, we can also estimate the time‐lag accompanied with the interaction between molecular components of a network.
TC1(C8orf4) is upregulated by IL‐1β/TNF‐α and enhances proliferation of human follicular dendritic cells
Authors: Kim Youngmi , Kim Jungtae , Park Juhee , Bang Seunghyun , Jung Yusun , Choe Jongseon , Song Kyuyoung , Lee Inchul
Published: May 2006

Follicular dendritic cells (FDC) play crucial roles in immune regulation. TNF‐α has been shown to be essential to the FDC network. However, the molecular regulation of FDC proliferation has not been characterized. Here, we show that TC1(C8orf4), a novel positive regulator of the Wnt/β‐catenin pathway in vertebrates, is upregulated by IL‐1β and TNF‐α in the human FDC‐like line HK. TC1 enhances HK cell proliferation, while TC1‐knockdown inhibits the proliferation induced by IL‐1β, suggesting a role of TC1 as a regulator of FDC proliferation. The regulation by pro‐inflammatory cytokines suggests that TC1 might be implicated in linking local inflammation to immune response by stimulating FDC.
MEX is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis
Authors: Nishito Yasumasa , Hasegawa Mizuho , Inohara Naohiro , Núñez Gabriel
Published: May 2006

In the present study, we report the identification and characterization of MEX (MEKK1-related protein X), a protein with homology to MEKK1 that is expressed uniquely in the testis. MEX is comprises four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain of unknown function and two RING (really interesting new gene) fingers separated by a ZZ zinc finger domain. Biochemical analyses revealed that MEX is self-ubiquitinated and targeted for degradation through the proteasome pathway. MEX can act as an E3, Ub (ubiquitin) ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c or UbcH6. A region of MEX that contains the RING fingers and the ZZ zinc finger was required for interaction with UbcH5a and MEX self-association, whereas the SWIM domain was critical for MEX ubiquitination. The expression of MEX promoted apoptosis that was induced through Fas, DR (death receptor) 3 and DR4 signalling, but not that mediated by the BH3 (Bcl-2 homology 3)-only protein BimEL or the chemotherapeutic drug adriamycin. The enhancement of apoptosis by MEX required a functional SWIM domain, suggesting that MEX ubiquitination is critical for the enhancement of apoptosis. These results indicate that MEX acts as an E3 Ub ligase, an activity that is dependent on the SWIM domain and suggest a role for MEX in the regulation of death receptor-induced apoptosis in the testes.
Transcriptional activation of a moderately expressed tRNA gene by a positioned nucleosome
Authors: Parthasarthy Akhila , Gopinathan Karumathil P.
Published: May 2006

All of the members of a tRNA1Gly multigene family from the mulberry silkworm, Bombyx mori, have identical coding regions and consequently identical internal promoter elements, but are transcribed at different levels. A moderately expressed copy, tRNA1Gly-4 from within this multigene family, which was transcribed to 30–50% of the highly transcribed gene copies harboured two typical TATAA box sequences in the 5′ upstream region at positions −27 nt and −154 nt with respect to the +1 nt of mature tRNA. Deletion of the distal TATAA sequence at −154 nt brought down the transcription more than 70%, whereas mutation of the proximal element did not affect transcription. tRNA1Gly-4 could be readily assembled into chromatin, with a positioned nucleosome in the upstream region, and the assembled nucleosome formed stable complexes with the transcription factors TFIIIC and TFIIIB. Organization of the gene into nucleosomes also enhanced transcription significantly above that of the naked DNA, reaching transcription levels comparable with those of the highly transcribed copies. This nucleosome-mediated enhancement in transcription was absent when the distal TATAA sequences were deleted, whereas mutation of the proximal TATAA element showed no effect. In the absence of the distal TATAA sequences, assembly into the nucleosome inhibited transcription of tRNA1Gly-4. TFIIIB bound directly through the distal TATAA sequence at −154 nt and the positioned nucleosome facilitated its interaction with TFIIIC. The direct binding of TFIIIB to the DNA provided anchoring of the factor to the template DNA which conferred a higher stability on the TFIIIB–TFIIIC–DNA complex. We have proposed a novel mechanism for the nucleosome-mediated stimulation of pol III (RNA polymerase III) transcription of tRNA genes, a model not presented previously.
In vitro reconstitution of the GTPase-associated centre of the archaebacterial ribosome: the functional features observed in a hybrid form with Escherichia coli 50S subunits
Authors: Nomura Takaomi , Nakano Kohji , Maki Yasushi , Naganuma Takao , Nakashima Takashi , Tanaka Isao , Kimura Makoto , Hachimori Akira , Uchiumi Toshio
Published: May 2006

We cloned the genes encoding the ribosomal proteins Ph (Pyrococcus horikoshii)-P0, Ph-L12 and Ph-L11, which constitute the GTPase-associated centre of the archaebacterium Pyrococcus horikoshii. These proteins are homologues of the eukaryotic P0, P1/P2 and eL12 proteins, and correspond to Escherichia coli L10, L7/L12 and L11 proteins respectively. The proteins and the truncation mutants of Ph-P0 were overexpressed in E. coli cells and used for in vitro assembly on to the conserved domain around position 1070 of 23S rRNA (E. coli numbering). Ph-L12 tightly associated as a homodimer and bound to the C-terminal half of Ph-P0. The Ph-P0·Ph-L12 complex and Ph-L11 bound to the 1070 rRNA fragments from the three biological kingdoms in the same manner as the equivalent proteins of eukaryotic and eubacterial ribosomes. The Ph-P0·Ph-L12 complex and Ph-L11 could replace L10·L7/L12 and L11 respectively, on the E. coli 50S subunit in vitro. The resultant hybrid ribosome was accessible for eukaryotic, as well as archaebacterial elongation factors, but not for prokaryotic elongation factors. The GTPase and polyphenylalanine-synthetic activity that is dependent on eukaryotic elongation factors was comparable with that of the hybrid ribosomes carrying the eukaryotic ribosomal proteins. The results suggest that the archaebacterial proteins, including the Ph-L12 homodimer, are functionally accessible to eukaryotic translation factors.
Hyaluronan: the absence of amide–carboxylate hydrogen bonds and the chain conformation in aqueous solution are incompatible with stable secondary and tertiary structure models
Authors: Blundell Charles D. , Deangelis Paul L. , Almond Andrew
Published: May 2006

Contradictory descriptions for the aqueous solution conformation of the glycosaminoglycan hyaluronan (HA) exist in the literature. According to hydrodynamic and simulation data, HA molecules are stiffened by a rapidly interchanging network of transient hydrogen bonds at the local level and do not significantly associate at the global level. In marked contrast, models derived from NMR data suggest that the secondary structure involves persistent hydrogen bonds and that strong associations between chains can occur to form vast stable tertiary structures. These models require an extended 2-fold helical conformation of the HA chain and specific hydrogen bonds between amide and carboxylate groups. To test these descriptions, we have used 15N-labelled oligosaccharides and high-field NMR to measure pertinent properties of the acetamido group. The amide proton chemical shift perturbation and carboxylate group pKa value are inconsistent with a highly populated hydrogen bond between the amide and carboxylate groups. Amide proton temperature coefficients and chemical exchange rates confirm this conclusion. Comparison of oligomer properties with polymeric HA indicates that there is no discernible difference in amide proton environment between the centre of octasaccharides and the polymer, inconsistent with the formation of tertiary structures. A [1H-1H-15N] NOESY-HSQC (heteronuclear single-quantum correlation) spectrum recorded on an HA octasaccharide revealed that amide groups in the centre are in a trans orientation and that the average solution conformation is not an extended 2-fold helix. Therefore the two key aspects of the secondary and tertiary structure models are unlikely to be correct. Rather, these new NMR data agree with descriptions from hydrodynamic and simulations data.
Formation of hydrogen-bridged cytosine dimers on Cu(110)
Authors: Frankel D. J. , Chen Q. , Richardson N. V.
Published: May 2006

Cytosine was adsorbed onto a Cu(110) surface under UHV conditions. Annealing to 370K resulted in the formation of a (6×6)gg low energy electron diffraction (LEED) pattern, even at submonolayer coverages. Examination of this structure with scanning tunneling microscopy (STM) revealed islands of zigzag chains at low coverages and large ordered domains at monolayer saturation. Further annealing to 480K initiated a phase transition to a (6×2)gg structure observed both by LEED and STM. High resolution electron energy loss spectroscopy spectra for both overlayer structures exhibited mainly in-plane modes suggesting upright/tilted species on the surface. Based on the experimental data and supported by density functional theory calculations, a model is proposed for the (6×2)gg structure, which involves the formation of deprotonated hydrogen bridge-bonded cytosine dimers, adsorbed through the oxygen atoms.
Experimental long range potential of the BΠ1 state in NaRb
Authors: Pashov A. , Jastrzebski W. , Kortyka P. , Kowalczyk P.
Published: May 2006

The long range potential of the BΠ1 state in NaRb has been investigated by observation of rovibrational levels that it supports, including the high lying ones, with the technique of polarization labeling spectroscopy. This has allowed us to characterize the potential energy curve up to 1.9cm−1 from the dissociation limit. The highest observed rovibrational level v=49, J=10 has the outer turning point at R=16.48Å.
Permeative flows in cholesterics: Shear and Poiseuille flows
Authors: Marenduzzo D. , Orlandini E. , Yeomans J. M.
Published: May 2006

By using a lattice Boltzmann scheme that solves the Beris-Edwards equations of motion describing liquid-crystal hydrodynamics, we study the response of cholesterics to shear and Poiseuille flows. The geometry we focus on is a flow along the direction of the helical axis, which is known to give rise to permeation. For both shear and Poiseuille flow we find that the boundary conditions on the director field are crucial in determining the rheological properties of the liquid crystal. For helices pinned at the boundaries, a small forcing leads to a large viscosity increase whereas a stronger forcing induces a sharp decrease towards the Newtonian value. This shear thinning behavior is in agreement with experiments and previous analytic results. If, on the other hand, the director is free to rotate at the walls, different behaviors are found depending on the symmetry of the steady-state primary flow. Some of the cases considered are compared to a similar imposed flow but with the helix lying perpendicular to the plates, for which no viscosity increase is observed.
Influence of metallic nanoparticles on the performance of organic electrophosphorescence devices
Authors: Choulis Stelios A. , Mathai Mathew K. , Choong Vi-En
Published: May 2006

We investigate the influence of metallic nanoparticles on the performance of phosphorescence organic light emitting diodes. The metallic nanoparticles display appropriate surface plasmon resonances in the visible region of the spectrum close to the emission band of the triplet emitter to accelerate the spontaneous emission rate of the phosphorescence compound. We have incorporated gold nanoparticles in the interface between alternative buffer layers and a phosphorescence based light emitting layer. In the case of AI4083 poly(3,4-ethylenedioxy thiophene):poly(styrene sulfonate) buffer layer, the interface modification with gold nanoparticles results in a 33% improvement in the luminance efficiency of tris(2-4(4-toltyl)phenylpyridine) iridium based phosphorescence organic light emitting diodes.
Boron as an anti-surfactant in sublimation growth of AlN single crystals
Authors: Albrecht M. , Wollweber J. , Rossberg M. , Schmidbauer M. , Hartmann C. , Fornari R.
Published: May 2006

We study the influence of B evaporating from BN crucible walls on the nucleation and growth of AlN by a physical vapor transport. An experimental analysis by means of electron microscopy and optical spectroscopy shows that B incorporation and surface segregation depends on the orientation of the respective surface facet. Surface segregation is found to be predominant on {11-20} facets. This leads to the formation of wurtzite BN nuclei on these facets which extend over the whole surface and may form closed layers. Both boron surface segregation and growth of BN nuclei influence Al and N adsorption and surface diffusion, and in consequence reduce the growth rate. The differences in surface segregation of B on different facets can be understood in terms of incorporation kinetics of boron adatoms into the AlN crystal. B thus acts as a facet selective antisurfactant.
Tunnel oxide thickness dependence of activation energy for retention time in SiGe quantum dot flash memory
Authors: Liu Yueran , Tang Shan , Banerjee Sanjay K.
Published: May 2006

In this letter, we have studied the temperature dependence of retention time of SiGe dot floating-gate flash memory with different tunnel oxide thicknesses, and compared the difference of the activation energy between them. The results showed that the electrons are stored in the deep trap states in semiconductor quantum dot floating gate after programing, and those states are localized at few hundred meV below the semiconductor conduction band.
Effect of normal vibration on friction in the atomic force microscopy experiment
Authors: Jeon Sangmin , Thundat Thomas , Braiman Yehuda
Published: May 2006

We studied the effect of periodic normal (out-of-plane) surface vibrations on friction in an atomic force microscope experiment. Vibration frequency was varied in the range of 1–100kHz, and vibration amplitude was varied in the range of a few nanometers. We observed a reduction of a few orders of magnitude in friction coefficient due to the periodic vibrations. Friction reduction is over a wide range of vibration frequencies and amplitudes. Very low values (of the order of 0.01) of friction coefficient were measured. Our numerical simulation based on a minimalist modeling qualitatively agrees with the experimental results. Based on numerical simulations, a mechanism of friction reduction and/or increase with normal vibrations is proposed.
International Innovation Comparisons: Insight or Illusion?
Authors: Roper Stephen , Hewitt-Dundas Nola
Published: May 2006

Recent developments in statistical methodology have facilitated international innovation comparisons. These, however, inevitably reflect both the industrial structure of the underlying economies, and the innovativeness of firms within each element of the industrial structure. The authors consider the extent to which structural differences between economies can influence international innovation comparisons. The impact of structural differences is considered both in conceptual and in empirical terms, with the aid of data from the first and second Community Innovation Surveys (CIS 1 and CIS 2). Conceptual analysis suggests a very restricted range of scenarios under which structural adjustment will be effective. Empirical results are more reassuring, however, suggesting that, although structural effects are in some cases quite large, they do not significantly distort international innovation relativities. The comparisons do, however, highlight significant inconsistencies between different innovation indicators and suggest policy priorities.
E-Participation in Planning: An Analysis of Cities Adopting On-Line Citizen Participation Tools
Authors: Conroy Maria Manta , Evans-Cowley Jennifer
Published: May 2006

E-government tools provide municipal planning departments with an alternative means to inform and engage their citizenry. We examine the use of information and communication technology e-government tools to promote citizen participation in the planning process. The analysis is based on an examination of municipal planning-related websites for the 590 US cities with a 2000 Census population of 50 000 or more. We also explore the influence which demographic contextual factors have on what tools are provided. Principal findings highlight the dominance of simple, information-based, e-government tools. The analyses also suggest that population-related and geographic-related variables are significant and pervasive influences on the provision of these tools.
Learning the Moves: The Effect of Familiarity and Facial Motion on Person Recognition across Large Changes in Viewing Format
Authors: Roark Dana A , O'Toole Alice J , Abdi Hervé , Barrett Susan E
Published: May 2006

Familiarity with a face or person can support recognition in tasks that require generalization to novel viewing contexts. Using naturalistic viewing conditions requiring recognition of people from face or whole body gait stimuli, we investigated the effects of familiarity, facial motion, and direction of learning/test transfer on person recognition. Participants were familiarized with previously unknown people from gait videos and were tested on faces (experiment 1a) or were familiarized with faces and were tested with gait videos (experiment 1b). Recognition was more accurate when learning from the face and testing with the gait videos, than when learning from the gait videos and testing with the face. The repetition of a single stimulus, either the face or gait, produced strong recognition gains across transfer conditions. Also, the presentation of moving faces resulted in better performance than that of static faces. In experiment 2, we investigated the role of facial motion further by testing recognition with static profile images. Motion provided no benefit for recognition, indicating that structure-from-motion is an unlikely source of the motion advantage found in the first set of experiments.
Newcastle disease virus expressing H5 hemagglutinin gene protects chickens against Newcastle disease and avian influenza
Authors: Veits Jutta , Wiesner Dorothee , Fuchs Walter , Hoffmann Bernd , Granzow Harald , Starick Elke , Mundt Egbert , Schirrmeier Horst , Mebatsion Teshome , Mettenleiter Thomas C. , Römer-Oberdörfer Angela
Published: May 2006

Newcastle disease virus (NDV)-expressing avian influenza virus (AIV) hemagglutinin (HA) of subtype H5 was constructed by reverse genetics. A cloned full-length copy of the genome of the lentogenic NDV strain Clone 30 was used for insertion of the ORF encoding the HA of the highly pathogenic AIV isolate A/chicken/Italy/8/98 (H5N2) in the intergenic region between the NDV fusion and hemagglutinin-neuraminidase (HN) genes. Remarkably, two species of HA transcripts were detected in cells infected with the resultant NDVH5. In a second recombinant (NDVH5m), a NDV transcription termination signal-like sequence located within the HA ORF was eliminated by silent mutations. Consequently, NDVH5m produced 2.7-fold more full-length HA transcripts, expressed higher levels of HA, and also incorporated more HA protein into its envelope than NDVH5. NDVH5m stably expressed the modified HA gene for 10 egg passages and both recombinants were found innocuous after intracerebral inoculation of 1-day-old chickens. Immunization of chickens with NDVH5m induced NDV- and AIVH5-specific antibodies and protected chickens against clinical disease after challenge with a lethal dose of velogenic NDV or highly pathogenic AIV, respectively. Remarkably, shedding of influenza virus was not observed. Furthermore, immunization with NDVH5m permitted serological discrimination of vaccinated and AIV field virus-infected animals based on antibodies against the nucleoprotein of AIV. Therefore, recombinant NDVH5m is suitable as a bivalent vaccine against NDV and AIV and may be used as marker vaccine for the control of avian influenza.
Engineered viral vaccine constructs with dual specificity: Avian influenza and Newcastle disease
Authors: Park Man-Seong , Steel John , García-Sastre Adolfo , Swayne David , Palese Peter
Published: May 2006

Avian influenza viruses of the H5 and H7 hemagglutinin subtypes, and Newcastle disease virus (NDV), are important pathogens in poultry worldwide. Specifically, the highly pathogenic H5N1 avian influenza virus is a particular threat because it has now occurred in more than 40 countries on several continents. Inasmuch as most chickens worldwide are vaccinated with a live NDV vaccine, we embarked on the development of vaccine prototypes that would have dual specificity and would allow a single immunization against both avian influenza and Newcastle disease. Using reverse genetics, we constructed a chimeric avian influenza virus that expressed the ectodomain of the hemagglutinin-neuraminidase gene of NDV instead of the neuraminidase protein of the H5N1 avian influenza virus. Our second approach to creating a bivalent vaccine was based on expressing the ectodomain of an H7 avian influenza virus hemagglutinin in a fusogenic and attenuated NDV background. The insertion into the NDV genome of the foreign gene (containing only its ectodomain, with the transmembrane and cytoplasmic domains derived from the F protein of NDV) resulted in a chimeric virus with enhanced incorporation of the foreign protein into virus particles. A single immunization of chickens with this improved vaccine prototype virus induced not only a 90% protection against an H7N7 highly pathogenic avian influenza virus, but also complete immunity against a highly virulent NDV. We propose that chimeric constructs should be developed for convenient, affordable, and effective vaccination against avian influenza and Newcastle disease in chickens and other poultry.
A missing model in reproductive skew theory: The bordered tug-of-war
Authors: Reeve Hudson Kern , Shen Sheng-Feng
Published: May 2006

Models of reproductive skew can be classified into two groups: transactional models, in which group members yield shares of reproduction to each other in return for cooperation, and tug-of-war models, in which group members invest group resources in a tug-of-war over their respective reproductive shares. We synthesize these two models to yield a “bordered tug-of-war” model in which the internal tug-of-war is limited (“bordered”) by the requirement that group members must achieve a certain amount of reproduction lest they pursue a noncooperative option leading to group breakup. Previous attempts to synthesize these two models did not allow for the fact that the tug-of-war will affect group output, which in turn feeds back on the reproductive payments required by group members to remain cooperative. The bordered tug-of-war model, which does not assume complete reproductive control by any individual and allows for conflict within groups, predicts that the degree of within-group selfishness will increase as the noncooperative options become less attractive, e.g., as ecological constraints on solitary breeding increase. When the noncooperative option involves fighting for the group resource (e.g., territory) and leaving if the fight is lost, the subordinate's overall share of reproduction is predicted to be independent of its relatedness to the dominant and to increase the greater its probability of winning the fight, the less the value of the territory, and the greater its personal payoff for leaving. The unique predictions of the bordered tug-of-war model may fit skew data from a number of species, including meerkats, lions, and wood mice.