bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismic migration with inverse Q filtering
Authors: Wang Yanghua , Guo Jian
Published: November 2004

Taking account the earth Q effect (i.e., frequency‐dependent amplitude decay and velocity dispersion) during seismic migration simultaneously, the resultant seismic image is expected to be high resolution with true amplitude and correct timing. We present here a stabilized algorithm for such a “migration incorporating inverse Q filtering” scheme, so that the imaging technique is applicable to seismographs with long recording time. The earth model is assumed to be 1‐D with continuous variations vertically in velocity and attenuation, and the imaging algorithm is implemented easily and efficiently in the frequency‐wavenumber domain. Although such a 1‐D model suits mostly to the cases in lithospheric‐scale regional geophysics, it is sometimes also suitable to the exploration seismic studies. The method is demonstrated using a real data example from exploration seismics with an attempt to recover a target reflection underneath a group of strong coal‐seam reflections.
GW9662, a potent antagonist of PPARγ, inhibits growth of breast tumour cells and promotes the anticancer effects of the PPARγ agonist rosiglitazone, independently of PPARγ activation
Authors: Seargent Jill M , Yates Elisabeth A , Gill Jason H
Published: November 2004

Peroxisome proliferator‐activated receptor gamma (PPARγ), a member of the nuclear receptor superfamily, is activated by several compounds, including the thiazolidinediones. In addition to being a therapeutic target for obesity, hypolipidaemia and diabetes, perturbation of PPARγ signalling is now believed to be a strategy for treatment of several cancers, including breast. Although differential expression of PPARγ is observed in tumours compared to normal tissues and PPARγ agonists have been shown to inhibit tumour cell growth and survival, the interdependence of these observations is unclear. This study demonstrated that the potent, irreversible and selective PPARγ antagonist GW9662 prevented activation of PPARγ and inhibited growth of human mammary tumour cell lines. Controversially, GW9662 prevented rosiglitazone‐mediated PPARγ activation, but enhanced rather than reversed rosiglitazone‐induced growth inhibition. As such, these data support the existence of PPARγ‐independent pathways and question the central belief that PPARγ ligands mediate their anticancer effects via activation of PPARγ.

British Journal of Pharmacology (2004) 143, 933–937. doi:10.1038/sj.bjp.0705973
Inhibition of ATP‐sensitive potassium channels by haloperidol
Authors: Yang Shi‐Bing , Proks Peter , Ashcroft Frances M , Rupnik Marjan
Published: November 2004

Chronic haloperidol treatment has been associated with an increased incidence of glucose intolerance and type‐II diabetes mellitus. We studied the effects of haloperidol on native ATP‐sensitive potassium (KATP) channels in mouse pancreatic β cells and on cloned Kir6.2/SUR1 channels expressed in HEK293 cells.

The inhibitory effect of haloperidol on the KATP channel was not mediated via the D2 receptor signaling pathway, as both D2 agonists and antagonists blocked the channel.

KATP currents were studied using the patch‐clamp technique in whole‐cell and outside‐out patch configurations. Addition of haloperidol to the extracellular solution inhibited the KATP conductance immediately, in a reversible and voltage‐independent manner. Haloperidol did not block the channel when applied intracellularly in whole‐cell recordings.

Haloperidol blocked cloned Kir6.2/SUR1 and Kir6.2ΔC36 KATP channels expressed in HEK cells. This suggests that the drug interacts with the Kir6.2 subunit of the channel.

The IC50 for inhibition of the KATP current by haloperidol was 1.6 μM in 2 mM extracellular K+ concentration ([K+]o) and increased to 23.9 μM in 150 mM [K+]o. The Hill coefficient was close to unity, suggesting that the binding of a single molecule of haloperidol is sufficient to close the channel.

Haloperidol block of KATP channels may contribute to the side effects of this drug when used therapeutically.

British Journal of Pharmacology (2004) 143, 960–967. doi:10.1038/sj.bjp.0706017
Characterization of a transport and detoxification pathway for the antitumour drug bleomycin in Saccharomyces cerevisiae
Authors: AOUIDA Mustapha , LEDUC Anick , WANG Huijie , RAMOTAR Dindial
Published: November 2004

BLM (bleomycin) is effective in combination therapy against various cancers including testicular cancer. However, several other cancers such as colon cancer are refractory to BLM treatment. The exact mechanism for this differential response of cancer cells to the drug is not known. In the present study, we created fluorescently labelled BLM-A5, which retained nearly full genotoxic potential, and used this molecule to conduct the first study to understand the transport pathway of the drug in Saccharomyces cerevisiae. Uptake studies revealed that fluoro-BLM-A5 is transported into the cell in a concentration-dependent manner. Transport of a non-saturating concentration of fluoro-BLM-A5 was modest for the first 90 min, but thereafter it was sharply induced until 300 min. The inducible transport was completely abolished by the addition of cycloheximide, suggesting that BLM-A5 uptake into the cell is dependent on new protein synthesis. Interestingly, transport of fluoro-BLM-A5 was blocked if the cells were preincubated with increasing concentrations of spermine. Moreover, a mutant lacking the Ptk2 kinase, necessary for positively regulating polyamine transport, was defective in fluoro-BLM-A5 uptake and exhibited extreme resistance to the drug. A simple interpretation of these results is that BLM-A5 may enter the cell through the polyamine transport system. We showed further that after the uptake, fluoro-BLM-A5 accumulated into the vacuole of the parent, but localized to the cytoplasm of mutants disrupted for the END3 gene required for an early step of the endocytotic pathway. In general, mutants with a defect in the endocytic pathway to the vacuole were hypersensitive to BLM-A5. We suggest that BLM-A5 is transported across the yeast plasma membrane and sequestered into the vacuole for detoxification.
Effects of deletions at the C-terminus of tobacco acetohydroxyacid synthase on the enzyme activity and cofactor binding
Authors: KIM Joungmok , BEAK Dong-Gil , KIM Young-Tae , CHOI Jung-Do , YOON Moon-Young
Published: November 2004

AHAS (acetohydroxyacid synthase) catalyses the first committed step in the biosynthesis of branched-chain amino acids, such as valine, leucine and isoleucine. Owing to the unique presence of these biosynthetic pathways in plants and micro-organisms, AHAS has been widely investigated as an attractive target of several classes of herbicides. Recently, the crystal structure of the catalytic subunit of yeast AHAS has been resolved at 2.8 Å (1 Å=0.1 nm), showing that the active site is located at the dimer interface and is near the herbicide-binding site. In this structure, the existence of two disordered regions, a ‘mobile loop’ and a C-terminal ‘lid’, is worth notice. Although these regions contain the residues that are known to be important in substrate specificity and in herbicide resistance, they are poorly folded into any distinct secondary structure and are not within contact distance of the cofactors. In the present study, we have tried to demonstrate the role of these regions of tobacco AHAS by constructing variants with serial deletions, based on the structure of yeast AHAS. In contrast with the wild-type AHAS, the truncated mutant which removes the C-terminal lid, Δ630, and the internal deletion mutant without the mobile loop, Δ567–582, impaired the binding affinity for ThDP (thiamine diphosphate), and showed different elution profiles representing a monomeric form in gel-filtration chromatography. Our results suggest that these regions are involved in the binding/stabilization of the active dimer and ThDP binding.
Guanidinium chloride denaturation of the dimeric Bacillus licheniformis BlaI repressor highlights an independent domain unfolding pathway
Authors: VREULS Christelle , FILÉE Patrice , VAN MELCKEBEKE Hélène , AERTS Tony , DE DEYN Peter , LLABRÈS Gabriel , MATAGNE André , SIMORRE Jean-Pierre , FRÈRE Jean-Marie , JORIS Bernard
Published: November 2004

The Bacillus licheniformis 749/I BlaI repressor is a prokaryotic regulator that, in the absence of a β-lactam antibiotic, prevents the transcription of the blaP gene, which encodes the BlaP β-lactamase. The BlaI repressor is composed of two structural domains. The 82-residue NTD (N-terminal domain) is a DNA-binding domain, and the CTD (C-terminal domain) containing the next 46 residues is a dimerization domain. Recent studies have shown the existence of the monomeric, dimeric and tetrameric forms of BlaI in solution. In the present study, we analyse the equilibrium unfolding of BlaI in the presence of GdmCl (guanidinium chloride) using different techniques: intrinsic and ANS (8-anilinonaphthalene-l-sulphonic acid) fluorescence, far- and near-UV CD spectroscopy, cross-linking, analytical ultracentrifugation, size exclusion chromatography and NMR spectroscopy. In addition, the intact NTD and CTD were purified after proteolysis of BlaI by papain, and their unfolding by GdmCl was also studied. GdmCl-induced equilibrium unfolding was shown to be fully reversible for BlaI and for the two isolated fragments. The results demonstrate that the NTD and CTD of BlaI fold/unfold independently in a four-step process, with no significant co-operative interactions between them. During the first step, the unfolding of the BlaI CTD occurs, followed in the second step by the formation of an ‘ANS-bound’ intermediate state. Cross-linking and analytical ultracentrifugation experiments suggest that the dissociation of the dimer into two partially unfolded monomers takes place in the third step. Finally, the unfolding of the BlaI NTD occurs at a GdmCl concentration of approx. 4 M. In summary, it is shown that the BlaI CTD is structured, more flexible and less stable than the NTD upon GdmCl denaturation. These results contribute to the characterization of the BlaI dimerization domain (i.e. CTD) involved in the induction process.
Regulation of actin cytoskeleton by mDab1 through N-WASP and ubiquitination of mDab1
Authors: SUETSUGU Shiro , TEZUKA Tohru , MORIMURA Toshifumi , HATTORI Mitsuharu , MIKOSHIBA Katsuhiko , YAMAMOTO Tadashi , TAKENAWA Tadaomi
Published: November 2004

Migration of cells is critical to development of the central nervous system. Reelin, which was identified from the reeler mutant mice having a defect in the multilamellar structure of the brain, is thought to be a key signalling molecule that functions as a cue for determination of cell position. mDab1 (mouse Disabled homologue 1) functions downstream of Reelin. However, the mechanism by which mDab1 regulates cell migration during brain development is unknown. In the present paper, we show that mDab1 associates with N-WASP (neuronal Wiskott–Aldrich syndrome protein) in vitro and in brains of embryonic mice. mDab1 activates N-WASP directly, and induces actin polymerization through the Arp2/3 (actin-related protein 2/3) complex. mDab1 induces formation of filopodia when it is overexpressed in COS-7 cells. This filopodium formation is dependent on N-WASP, because expression of an N-WASP mutant that cannot induce Arp2/3-complex-mediated actin polymerization suppressed filopodium formation. The PTB (phosphotyrosine-binding) domain of mDab1 binds to N-WASP via the NRFY (Asn-Arg-Phe-Tyr) sequence close to the CRIB (Cdc42/Rac-interactive binding) motif of N-WASP and activates N-WASP in vitro. When mDab1 is phosphorylated by Fyn kinase in COS-7 cells, mDab1 is ubiquitinated in a Cbl-dependent manner, and mDab1 does not induce filopodium in the presence of activated Fyn. These findings suggest that mDab1 regulates the actin cytoskeleton through N-WASP, which is negatively regulated by phosphorylation-mediated ubiquitination of mDab1.
Activation of Arp2/3 complex-dependent actin polymerization by plant proteins distantly related to Scar/WAVE
Authors: Frank Mary , Egile Coumaran , Dyachok Julia , Djakovic Stevan , Nolasco Michelle , Li Rong , Smith Laurie G.
Published: November 2004

The Arp2/3 complex, a highly conserved nucleator of F-actin polymerization, plays a key role in the regulation of actin dynamics eukaryotic cells. In animal cells and yeasts, Wiskott-Aldrich Syndrome protein (WASP)/suppressor of cAMP receptor (Scar)/WASP family verprolin homologous (WAVE) family proteins activate the Arp2/3 complex in response to localized cues. Like other eukaryotes, plants have an Arp2/3 complex, which has recently been shown to play an important role in F-actin organization and cell morphogenesis. However, no activators of the Arp2/3 complex have been identified in plants, which lack obvious homologs of WASP/Scar/WAVE family proteins. Here, we identify a family of Scar/WAVE-related plant Arp2/3 activators. Like Scar/WAVE proteins, four proteins identified in
Arabidopsis thaliana
(AtSCAR1 to AtSCAR4) and one in maize (ZmSCAR1) have a C-terminal WASP homology 2 (WH2)/acidic (WA)-verprolin homology/cofilin homology/acidic (VCA)-like domain, which we show can activate the bovine Arp2/3 complex. At their N termini, AtSCAR1 to ATSCAR4, along with a fifth protein lacking a VCA/WA-like domain at its C terminus (At4g18600), are related to the N-terminal Scar homology domains of Scar/WAVE family proteins. Analysis of gene expression patterns suggests functional redundancy among members of the
AtSCAR
family. Full-length AtSCAR1 and ATSCAR3 proteins and their Scar homology domains bind
in vitro
to AtBRICK 1 (AtBRK1), the
Arabidopsis
homolog of HSPC300, a WAVE-binding protein recently identified as a component of a complex implicated in the regulation of Scar/WAVE activity. Thus, AtSCAR proteins are likely to function in association with AtBRK1, and perhaps other
Arabidopsis
homologs of WAVE complex components, to regulate activation of the Arp2,3 complex
in vivo
.
Tc1/Tc2 ratio in the inflammatory process in patients with Behçet′s disease
Authors: Houman Habib , Hamzaoui Agnes , Ghorbal Imed Ben , Khanfir Monia Smiti , Feki Moncef , Hamzaoui Kamel
Published: November 2004

BACKGROUND: Peripheral blood CD8+ T cells expressing interferon gamma and interleukin‐4 (IL‐4), and lacking CD28 molecules, were responsible for the dynamic interplay between peripheral blood and inflammatory sites.

Introduction: The aim of the current study was to define in Behçet′s disease (BD), CD8+ T‐cell subsets using CD28 and CD11b monoclonal antibodies, and the characterization of the Tc1/Tc2 ratio and perforin expression.

Methods: Flow cytometry was used for intracytoplasmic cytokines and perforin expression. Effector cells were investigated by adhesion of CD8+ T cells to human microvascular endothelial cells and by chemotaxis using β‐chemokine.

Results: Interferon‐gamma‐producing CD8+ T cells in active and remission BD patients were increased, which induce a significant increase of the Tc1:Tc2 ratio in BD. CD8+CD28−CD11b+ T cells were found to be more expanded in BD patients than in age‐matched healthy controls. The expression of CD11b molecules in active BD allowed to CD8+CD28+/CD8+CD28− subsets to adhere to human microvascular endothelial cells, with more efficiency in BD. Using MIP‐1α, we observed that the migratory process of CD28−CD11b+ is more important in BD. CD28−CD11b+ exhibited an increased perforin expression in BD patients.

Conclusion: Taken together these results suggest the presence of immune activation, probably in response to a profound inflammation affecting BD patients. The physiopathological significance of these results were toward autoimmune diseases and/or infectious process.
Circulating levels of cyclooxygenase metabolites in experimental Trypanosoma cruzi infections
Authors: Cardoni Rita L. , Antúnez María Inés
Published: November 2004

TRYPANOSOMA cruzi induces inflammatory reactions in several tissues. The production of prostaglandin F2α, 6‐keto‐prostaglandin F1α and thromboxane B2, known to regulate the immune response and to participate in inflammatory reactions, was studied in mice experimentally infected with T. cruzi. The generation of nitric oxide (NO), which could be regulated by cyclooxygenase metabolites, was also evaluated. In the acute infection the extension of inflammatory infiltrates in skeletal muscle as well as the circulating levels of cyclooxygenase metabolites and NO were higher in resistant C3H mice than in susceptible BALB/c mice. In addition, the spontaneous release of NO by spleen cells increased earlier in the C3H mouse strain. In the chronic infections, the tissue inflammatory reaction was still prominent in both groups of mice, but a moderate increase of thromboxane B2 concentration and in NO released by spleen cells was observed only in C3H mice. This comparative study shows that these mediators could be mainly related to protective mechanisms in the acute phase, but seem not to be involved in its maintenance in the chronic T. cruzi infections.
T Cell–specific Inactivation of the Interleukin 10 Gene in Mice Results in Enhanced T Cell Responses but Normal Innate Responses to Lipopolysaccharide or Skin Irritation
Authors: Roers Axel , Siewe Lisa , Strittmatter Elke , Deckert Martina , Schlüter Dirk , Stenzel Werner , Gruber Achim D. , Krieg Thomas , Rajewsky Klaus , Müller Werner
Published: November 2004

Interleukin (IL)-10 is a regulator of inflammatory responses and is secreted by a variety of different cell types including T cells. T regulatory cells have been shown to suppress immune responses by IL-10–dependent, but also IL-10–independent, mechanisms. Herein, we address the role of T cell–derived IL-10 in mice with an inactivation of the IL-10 gene restricted to T cells generated by Cre/loxP-mediated targeting of the IL-10 gene. Splenocytes from this T cell–specific mutant secrete increased amounts of proinflammatory cytokines after activation in vitro compared with show enhanced contact hypersensitivity reactions, and succumb to severe immunopathology upon infection with Toxoplasma gondii. Despite intact IL-10 genes in other cell types, the dysregulation of T cell responses observed in the T cell–specific IL-10 mutant closely resembles the phenotype in complete IL-10 deficiency. However, in contrast to complete IL-10 deficiency, sensitivity to endotoxic shock and irritant responses of the skin are not enhanced in the T cell–specific IL-10 mutant. Our data highlight the importance of T cell–derived IL-10 in the regulation of T cell responses and demonstrate that endotoxic shock and the irritant response of the skin are controlled by IL-10 from other cell types.
The 2000 Review of the OECD Guidelines for Multinational Enterprises
Authors: Tully Stephen
Published: November 2004

On 27 June 2000, the updated Guidelines for Multinational Enterprises (the Guidelines) were adopted by the 29 Member States of the Organisation for Economic Co-operation and Development (OECD) together with the observer governments of Argentina, Brazil, Chile and the Slovak Republic. The Ministerial Conference Chairman, Mr Peter Costello, described the 2000 Review as heralding the most “far reaching changes” to the Guidelines since their introduction in 1976.1 This note proposes to consider only the most noteworthy among them.2 Accordingly, it will not examine those elements that have merely been reaffirmed by the 2000 Review. However, the conclusions will be made that the Chairman's sentiments are only observable in the ongoing textual development of the Guidelines and that the all-important implementation mechanism has only been improved by half-measure
IV. Intellectual Property
Authors: McMahon Joe , Seville Catherine
Published: November 2004

This Journal's previous piece on current developments in EC intellectual property noted that this area of law is dominated by the drive towards harmonisation.1 This drive continues, and its success has been such that it can now begin to be seen in an overarching context of globalisation. The idea of a unified global system for the protection of intellectual property now seems at least conceivable, even if not immediately achievable. It is even possible to state that some stages have been achieved on the journey, most notably the TRIPs Agreement. Since adherence to this is a requirement of World Trade Organization (WTO) membership, the arguments in its favour have suddenly become “persuasive”. It represents a tremendous achievement in terms of the protection and enforcement of intellectual property rights throughout the world. The World Intellectual Property Organisation's contribution here and elsewhere has been immense.
The Resolution of the Institute of International Law on the Immunities of Heads of State and Government
Authors: Fox Hazel
Published: November 2004

A pressing issue of the day requiring authoritative resolution is whether public officials when in office carrying out their official functions may be prosecuted by the courts of other countries for alleged international crimes. Objection has been made, though not by the Danish Government, to a new ambassador appointed by the State of Israel, taking up his appointment as head of the Israeli diplomatic mission in Copenhagen, on the ground of his implication in war crimes. Recently, criminal proceedings were brought in the French courts against Colonel Ghadaffi as the serving Head of the State of Libya for complicity in acts of terrorism resulting in the destruction of a French civil aircraft and death of all its passengers. Writing critically of the Lords' decision in the Pinochet case, Henry Kissinger talks of the tyranny of judges replacing that of government, of prosecutorial discretion without accountability and warns that ‘historically the dictatorship of the virtuous has often led to inquisitions and witch hunts’.
I. International Law and Nuclear Weapons in Scottish Courts
Authors: Neff Stephen C.
Published: November 2004

Britain's Trident nuclear missile programme has long been politically controversial. In 1999, the controversy entered the judicial arena in Scotland, in two cases involving ‘direct action’ against Trident installations by anti-nuclear activists. In both cases, the actions were intended not as protests against Britain's nuclear-weapons policy, but rather as actual operations to disable the weapons themselves. The acts were, in other words, in the nature of acts of sabotage. Both incidents led to criminal prosecutions. In both cases, the accused parties sought to use international law as a defence. In both cases, the Appeal Court of the High Court of Justiciary—the highest court for criminal cases in Scotland—rejected the defence. In the process, however, the Appeal Court had occasion to expound upon some controversial points regarding nuclear weapons. Each of these cases will be discussed in turn.
Bills of Rights in Common Law Countries
Authors: McLachlin Beverley
Published: November 2004

On 17 April 2002, Canada will mark the 20th anniversary of the adoption of its bill of rights—the Charter of Rights and Freedoms. At the time, it seemed a momentous event to many, a strange thing to do. True, Canada was a bi-jural country, thanks to Quebec and the Civil Code. Nevertheless, the rest of the country sat solidly in the common law tradition. Codes, or so we thought, were anathema to common law systems that prided themselves on protection of rights through the incremental growth of precedent.
Pinochet Revisited
Authors: McLachlan Campbell
Published: November 2004

It is a measure of how fast International Law is moving that the International Court of Justice found itself deciding a question on immunity for international crimes just three years after Pinochet (No 3).1 Yet its decision in Congo v Belgium2 represents something of a return to conservatism in this field, and prompts a re-evaluation of Pinochet. Congo v Belgium may itself come to be seen as at least as significant for the ICJ's—divided—views on the issues which it did not decide, as for the ratio itself.
The Use of Military Courts to Try Suspects
Authors: Rogers APV
Published: November 2004

Of the thousands of Taliban and al Qaida fighters captured in the recent conflict in Afghanistan, just under 500 are held by US forces, including some 300 at the Guantanamo Bay base, Cuba.1
Article 6 Echr and Immunities Arising in Public International Law
Authors: Jones David LLoyd
Published: November 2004

The Procedural guarantees laid down in Article 6, European Convention on Human Rights in relation to the fairness and expedition of legal proceedings would be meaningless if the Convention did not protect the right of access to the courts which is a precondition to the enjoyment of those guarantees. As a result, the European Court of Human Rights has laid down the principle that Article 6(1) secures to everyone the right to have any claim relating to his civil rights and obligations brought before a court. The right of access to the courts is not absolute. The Strasbourg case law acknowledges that it may be subject to limitations. Contracting States enjoy a margin of appreciation in this regard. However, national courts must be satisfied that the limitations applied do not restrict or reduce the access left to the individual in such a way or to such an extent that the very essence of the right is impaired. Moreover a limitation will not be compatible with Article 6(1) if it does not pursue a legitimate aim and if there is no reasonable relationship of proportionality between the means employed and the aim sought to be achieved.
Social Policy
Authors: Szyszczak Erika
Published: November 2004

The Barcelona Summit of March 2002 provided the catalyst for further coordination and synchronisation between the social and economic dimensions of the Lisbon Strategy framework. The definition of the ‘European Social Model’ as ‘good economic performance, a high level of social protection and education and social dialogue’ has become a working definition underpinning the direction of social policy in official publications.1 The Barcelona Presidency also led to the adoption of a streamlined set of Employment Guidelines, Recommendations to the Member States and Broad Economic Policy Guidelines on the same day, heralded as an ‘instrument for economic governance’ by the Commission.2 The reform of the European Employment Strategy (EES) concentrates upon the problems and weaknesses of the EES identified in the evaluation of the first 5 years of the Strategy.3 The Commission identified four central issues for reform, focusing upon the need to set clear objectives (which include priorities and targets), the need to simplify the policy guidelines, the need to improve governance and ensure greater consistency and complementarity with other EU processes. A new development on the eve of the Spring Council (the Brussels Summit) on 20–21 March 2003 was a ‘Social Summit’ attended by a troika of the Heads of State/Government of the past, current and future Presidencies, the Commission and the Social Partners. One outcome of this Summit was the creation of a new eight-member task force, chaired by Wim Kok.4 The aim of the European Employment Task Force is to investigate practical steps to prompt the Member States to implement the new revised EES endorsed at the Spring Summit. The Task Force will report to the Commission in time to draft the Joint Employment Report for the annual Spring Summits.
Current Developments
Authors: Mceleavy Peter
Published: November 2004

Belgium has now become the second jurisdiction worldwide, after the Netherlands,1 to allow same-sex marriages. The bill opening marriage to persons of the same-sex and modifying certain provisions of the Civil Code2 was adopted by a large majority and without modification by the Belgian parliament on 30 January 2003. While the new law was promulgated by King Albert II on 13 February 2003 and published in the third edition of the Moniteur beige on 28 Febuary3, it did not enter into force until 1 June 2003. This somewhat unusual time delay was required to ensure that all officials with competence to celebrate marriages (officiers de I' état civil) had sufficient time to become familiar with the scope of the new rules.4
Structure for perovskites with layered ordering of A-site cations. Erratum
Authors: Howard Christopher J. , Zhang Zhaoming
Published: November 2004

The scheme of structures shown in Fig. 1 of the paper by Howard & Zhang (2004) is incomplete. Structures corresponding to different tilt systems, allowing but not requiring the layered ordering of A-site cations, were inadvertently omitted. The corrected version of this schematic is shown by Howard & Stokes (2004) as their Fig. 5. The additional structures can be shown to be unsuitable as candidate structures for the compounds considered by Howard & Zhang, so the arguments used by Howard & Zhang (2004) for structure identification remain unaffected.
Structures of stable and metastable Ge2Sb2Te5, an intermetallic compound in GeTe–Sb2Te3 pseudobinary systems
Authors: Matsunaga Toshiyuki , Yamada Noboru , Kubota Yoshiki
Published: November 2004

The most widely used memory materials for rewritable phase-change optical disks are the GeTe–Sb2Te3 pseudobinary compounds. Among these compounds, Ge2Sb2Te5 crystallizes into a cubic close-packed structure with a six-layer period (metastable phase) in the non-thermal equilibrium state, and a trigonal structure with a nine-layer period (stable phase) in the thermal equilibrium state. The structure of the stable phase has Ge/Sb layers in which Ge and Sb are randomly occupied, as does the structure of the metastable phase, while the conventionally estimated structure had separate layers of Ge and Te. The metastable and stable phases are very similar in that Te and Ge/Sb layers stack alternately to form the crystal. The major differences between these phases are: (i) the stable phase has pairs of adjacent Te layers that are not seen in the metastable phase and (ii) only the metastable phase contains vacancies of ca 20 at. % in the Ge/Sb layers.
The compression mechanism of CrF3
Authors: Jørgensen J.-E. , Marshall W. G. , Smith R. I.
Published: November 2004

The structure of CrF3 has been studied in the pressure range from ambient to 9.12 GPa by time-of-flight neutron powder diffraction. Rietveld refinements of the crystal structure were performed in the space group R\overline 3 c for all the recorded data sets. It was found that volume reduction is achieved through rotation of the CrF6 octahedra and that the Cr—F—Cr bond angle decreases from 144.80 (7) to 133.9 (4)° within the investigated pressure range. Furthermore, a small octahedral strain was found to develop during compression. The octahedral strain reflects an elongation of the CrF6 octahedra along the c-axis direction. The zero-pressure bulk modulus B

o
and its pressure derivative B_o^{\prime} were determined to be B

o
= 29.2 (4) GPa and B^{\prime}_o = 10.1 (3).
Phase transitions in K2Cr2O7 and structural redeterminations of phase II
Authors: Weakley T. J. R. , Ylvisaker E. R. , Yager R. J. , Stephens J. E. , Wiegel R. D. , Mengis M. , Bauer M. R. , Wu P. , Photinos P. , Abrahams S. C.
Published: November 2004

Crystals of phase II K2Cr2O7, potassium dichromate, space group P\overline 1, grown from aqueous solution undergo a first-order transition to phase I, space group reportedly P21/n, at a phase-transition temperature, T
PT, of 544 (2) K on first heating; the corresponding transition on cooling is at 502 (2) K. The endotherm on subsequent heatings occurs reproducibly at T
PT = 531 (2) K. Mass loss between ca 531 and 544 K, identified as included water, is rapid and continues more slowly to higher temperatures for a total loss of ca 0.20%. The higher T
PT on first heating is associated with the increasing pressure of superheated water occupying inclusion defects. The latent diagonal glide plane in phase II allows the structure of phase I to be inferred. The triclinic structure at 296 K has been independently redetermined. Normal probability analysis shows high consistency between the resulting and previous atomic coordinates, but with uncertainties reduced by a factor of ca 2. The earlier uncertainties are systematically underestimated by a comparable factor. The structure of phase IIb, space group A2/a on transposing axes, was determined at ca 300 K by Krivovichev et al. [Acta Cryst. (2000), C56, 629–630]. The first-order transition between phases I and II arises from the ca 60° relative rotation of terminal O atoms in each tetrahedron as the n glide plane is gained or lost. A transition between phases IIb and I, also of first order, is likely but not between phases II and IIb. An intermediate phase may exist between phases IIb and I.
Geometry of the 2-aminoheterocyclic–carboxylic acid R
2
2(8) graph set: implications for crystal engineering
Authors: Lynch Daniel E. , Jones Glyn D.
Published: November 2004

The geometry of the R_2^2(8) graph set formed between a 2-aminoheterocyclic ring containing an Nsp
2 atom (in the 1-position of the ring) and a carboxylic acid has been studied. Collating data from known co-crystal structures containing five- and six-membered heterocyclic rings from the Cambridge Structural Database revealed unexpected differences between two kinds of non-hydrogen contact distances, and between specific bond distances and angles of the heterocycle. Not only were the interatomic non-hydrogen distances between the N atoms (heterocycle) and O atoms (carboxylate) asymmetric, but also the 2-amino N atom (N21) to the heterocyclic C atom (C2) bond was shorter than the C2 to N1sp
2 bond. However, this shortening of the C2—N21 bond was not observed in the examples where N21 was substituted with a non-H atom. For the six-membered rings the data also showed that as the C2—N21 bond shortened the N1—C2—N21 bond angle increased.
Different forms of antiparallel stacking of hydrogen-bonded antidromic rings in the solid state: polymorphism with virtually the same unit cell and two-dimensional isostructurality with alternating layers
Authors: Kálmán Alajos , Fábián László , Argay Gyula , Bernáth Gábor , Cs. Gyarmati Zsuzsanna
Published: November 2004

As a continuation of a systematic structural analysis of 2-hydroxycycloalkanecarboxylic acids and their carboxamide analogs, the effects of antidromic rings [Jeffrey & Saenger (1991). Hydrogen Bonding in Biological Structures. Berlin, Heidelberg: Springer Verlag] upon the layer stacking of cyclopentane and cycloheptane derivatives are compared. Determination of the structure of trans-2-hydroxycycloheptanecarboxylic acid (2) led to the discovery of two polymorphs with virtually the same unit cell [Kálmán et al. (2003). J. Am. Chem. Soc.
125, 34–35]. (i) The layer stacking of the antidromic rings for the whole single crystal is antiparallel (2b). (ii) The antidromic rings and the 21 axis are parallel (2a), consequently the domains of the single crystal must be antiparallel. While their polymorphism is solvent-controlled, they illustrate a novel form of two-dimensional isostructurality. Antiparallel layer stacking is again demonstrated by trans-2-hydroxycycloheptanecarboxamide (3) (space group Pbca). It is built up from layers isostructural with those in the homologous trans-2-hydroxycyclopentanecarboxamide (4) [Kálmán et al. (2001). Acta Cryst. B57, 539–550], but in this structure (space group Pca21) the layers are stacked in parallel mode. Similar to (2a) and (2b), the antiparallel layer stacking in (3) versus their parallel array in (4) illustrates the two-dimensional isostructurality with alternating layer orientations. Although (3) and (4) display isostructurality, they are not isomorphous.
Structural investigations of phosphorus–nitrogen compounds. 6. Relationships between molecular parameters in per-X-substituted bridged spermine derivatives and basicity constants ΣαR of substituents
Authors: Coles Simon J , Davies David B. , Hursthouse Michael B. , Kiliç Adem , Mayer Thomas A. , Shaw Robert A. , Yenilmez Çiftçi Gonul
Published: November 2004

A systematic study is reported of the products of the nucleophilic substitution reactions of the spermine-bridged cyclotriphosphazene, [N3P3
X
4(NHCH2CH2CH2N)CH2CH2]2 [where X = Cl (2a)], to give a number of new structures [(2b)–(2g)] in which X = OPh, [spiro-O(CH2)3O]0.5, Ph, NHPh, NC4H8 and NHBu
t
, respectively. A comparison has been made between the sum of the substituent basicity constants, Σα
R
, obtained in nitrobenzene solution, and ten molecular parameters of the N3P3 ring (the internal bond angles α, β, γ, δ and θ, and the P—N bond lengths a, b, c, d and e) as well as the difference between the bond lengths a and b, Δ(P—N). It is found that the systematic change in molecular parameters of compounds (2a)–(2g) is in line with changes in α
R
values, indicating the similarity in relative electron-releasing capacity of substituents X in the solid state and in solution. It is also found that the effect on molecular parameters of (2a)–(2g) with two X substituents in PX
2 groups is greater than that for one X substituent in P(OR)X groups in an analogous series of compounds observed previously [Beşli et al. (2002). Acta Cryst. B58, 1067–1073].
Thermo-Mechanical Modeling of Hot Forging Process
Authors: Serajzadeh Siamak
Published: November 2004

In the present study, a mathematical model has been developed to evaluate temperature and strain fields as well as dynamic and static microstructural changes during the nonisothermal forging process. To do so, a finite element analysis and a microstructural model based on Bergstrom’s model have been coupled for predicting temperature history, velocity and strain fields as well as phase transformations within the metal during and after hot forging. To verify the results of the model, theoretical predictions for loadstroke behavior and austenite grain size have been compared with experimental results for two grades of steel.
Volumetric Constraint Models for Anisotropic Elastic Solids
Authors: Felippa Carlos A. , On˜ate Eugenio
Published: November 2004

We study three “incompressibility flavors” of linearly elastic anisotropic solids that exhibit volumetric constraints: isochoric, hydroisochoric, and rigidtropic. An isochoric material deforms without volume change under any stress system. An hydroisochoric material does so under hydrostatic stress. A rigidtropic material undergoes zero deformations under a certain stress pattern. Whereas the three models coalesce for isotropic materials, important differences appear for anisotropic behavior. We find that isochoric and hydroisochoric models under certain conditions may be hampered by unstable physical behavior. Rigidtropic models can represent semistable physical materials of arbitrary anisotropy while including isochoric and hydroisochoric behavior as special cases.
Study of Transverse Flow Effects on Particle Flows and Contamination of Air Bearing Sliders
Authors: Shen Xinjiang , Suk Mike , Bogy David B.
Published: November 2004

For some complex slider designs the two dimensional approximation incorporated in the Reynolds equation for determining the airflow in the air bearing is not applicable due to steps in the air bearing surface. A model that incorporates some transverse flow effects is needed to better characterize the airflow between the slider and disk for some applications. In this paper such a model is derived to better predict the paths of contamination particles entrained in the air bearing. The characteristics of airflow and particle flow within the air bearing are then studied. The analysis including the transverse effects reveals that the transverse velocity of the air is not negligible in the geometric transition regions of the slider. This transverse velocity has a significant effect on the flight path of particles, and therefore, on the particle contamination profile on slider surfaces. The assumption of adhesion of the particles upon impact with a surface is used as the contamination criteria, and it is viewed as the worst-case scenario.
Measurement of Adhesion Force and Elongation of Molecularly Thin Lubricant by Using Transient Response of SPM Cantilever
Authors: Ohshima Yasuji , Mitsuya Yasunaga , Iwase Yusuke
Published: November 2004

A novel method for identifying the adhesion force and dynamic elongation of molecularly thin lubricant coated over a DLC (diamond-like-carbon) surface was developed, in which those values were determined through the regression analysis of transient responses of an SPM (scanning probe microscopy) cantilever arising while separating from the target surface. The accuracy of measuring the cantilever displacement was greatly improved by mounting a silicon plate onto the cantilever as an optically reflective surface to produce a high quality image of the interference fringe pattern formed by Michelson interferometry. To analyze experimental transient vibration, a model to describe the separation process was introduced wherein the surface force decreases in proportion to the tip travel distance accompanying lubricant bridging. Based on this model, the adhesion force (contact force) and elongation of the lubricant were measured with varying retracting velocities. The results revealed that the contact force depends slightly on the velocity, and the lubricant elongates by several tens of times’ its original lubricant thickness.
A Nonlinear Structure Based Elastohydrodynamic Analysis Method for Connecting Rod Big End Bearings of High Performance Engines
Authors: Stefani Fabrizio A. , Rebora Alessandro U.
Published: November 2004

Big end bearings of connecting rods for high performance automotive engines are quite compliant and exhibit relatively large deformations at high rotation speed. Nowadays numerical simulation provides good estimate of tribological parameters for bearings operating in severe, but not extreme elastohydrodynamic lubrication conditions. At very high rotation speed regimes, reliable previsions are achieved only if an effort to increase the accuracy of structural modeling is accomplished. A finite element model able to account for the nonlinear friction controlled sliding phenomena occurring at the junction surface between the cap and the body of the rod has been developed. A new method to solve the coupled equations governing the interaction between the hydrodynamic fluid model and the nonlinear structural model of the connecting rod bearing is presented, together with a simple application example.
Rub-Groove Width and Depth Effects on Flow Predictions for Straight-Through Labyrinth Seals
Authors: Rhode David L. , Adams Richard G.
Published: November 2004

A fully compressible, two-dimensional axisymmetric, turbulent Navier-Stokes code using the finite-volume discretization approach was utilized to obtain an enhanced understanding of the effects of rub-grooves in straight-through, abradable labyrinth seals. The high-Re form of the k-ε turbulence model was used. The code was first validated against measurements of straight-through honeycomb labyrinths, and accurate results were obtained. It was found that in most of the cases considered (tooth tip outside of its rub groove), the presence of rub-grooves increases the leakage, except for the case of the large pre-rub clearance and narrow rub-groove width. The presence of the large- or the intermediate-width rub-grooves allows the rub-groove depth to exert a fairly large effect on the leakage, especially for the smallest pre-rub radial clearance. Further, the presence of a narrow rub-groove with the smallest pre-rub radial clearance gives a dramatic effect on the streamwise (i.e., cavity-to-cavity) variation in overall flow patten.
Effect of Loop Shape on the Drag-Induced Lift of Fly Line
Authors: Gatti-Bono Caroline , Perkins N. C.
Published: November 2004

This note explains why casting a loop with a positive angle of attack is advantageous in distance fly casting. Several loop shapes, one with a positive angle of attack, one with a negative angle of attack, and two symmetrical loops with zero angle of attack are studied. For each loop, we compute the vertical drag component, i.e., the “lift.” It is found that a loop with a positive angle of attack generates lift about four times larger than a symmetrical loop. Thus, loops with positive angles of attack stay “aerialized longer” which is consistent with observations made by (competition) distance fly casters.
Stability Criteria for Nonclassically Damped Systems With Nonlinear Uncertainties
Authors: Cao D. Q. , Ge Y. M. , Yang Y. R.
Published: November 2004

The asymptotic stability of nonclassically damped systems with nonlinear uncertainties is addressed using the Lyapunov approach. Bounds on nonlinear perturbations that maintain the stability of an asymptotically stable, linear multi-degree-of-freedom system with nonclassical damping are derived. The explicit nature of the construction permits us to directly express the algebraic criteria in terms of plant parameters. The results are then applied to the symmetric output feedback control of multi-degree-of-freedom systems with nonlinear uncertainties. Numerical examples are given to demonstrate the new stability criteria and to compare them with the previous results in the literature.
Sandwich Plates Actuated by a Kagome Planar Truss
Authors: Wicks N. , Hutchinson J. W.
Published: November 2004

Kagome truss plates have properties that suggest they should be uniquely effective as an actuation plane for sandwich plates: a Kagome truss plate has in-plane isotropy, optimal stiffness and strength, and its truss members can be actuated with minimal internal resistance. In this paper, sandwich plates are studied that are comprised of one solid face sheet and one actuated Kagome face sheet joined by a pyramidal truss core. Various aspects of the actuation behavior of these plates are investigated, including internal resistance and strains resulting from actuation and efficiency of actuation. Single and double curvature actuation modes are investigated. Contact is made with analytic results for actuation modes with long wavelength.
Mitigating the Effects of Local Flexibility at the Built-In Ends of Cantilever Beams
Authors: Wittwer Jonathan W. , Howell Larry L.
Published: November 2004

Local distortion at the built-in ends of cantilever beams can lead to significant errors when models assume the support to be perfectly rigid. This paper presents a novel approach for mitigating this effect, using appropriately sized fillets to provide the additional stiffness needed to make simplified models more accurate and reduce stress concentrations. The optimal nondimensional fillet radius, called the optimal fillet ratio, is shown to be nearly constant for a wide range of geometries under predominantly bending loads, making it a useful parameter in the design of planar monolithic flexible mechanisms.