bluuebunny/crossref_metadata_2025 huggingface dataset:
X‐ray photoelectron spectroscopy studies of chromium compounds
Authors: Biesinger M. C. , Brown C. , Mycroft J. R. , Davidson R. D. , McIntyre N. S.
Published: October 2004

Photoelectron spectra of a number of chromium oxides and other compounds were studied under high spectral resolution conditions chosen to reduce the possibility of differential charging. Some of the suite of Cr(III) compounds chosen for study produced Cr 2p spectra containing fine structure that could be identified with multiplet splitting. The splitting patterns produced were similar for all trivalent binary and ternary oxides and sulphides whose patterns closely reproduced the splitting predicted for the Cr(III) free ion by Gupta and Sen. The fine structure observed for compounds such as chromium (III) chloride had a distinctly different pattern. A number of other chromium (III) compounds were studied that did not exhibit the fine structure described above; nonetheless, well‐defined line shapes and reproducible peak centroids were obtained by fitting protocols. The use of such information to determine surface chemistry on chromated steels is described, based on the spectral knowledge of chromium (III) oxides and hydroxides and the chromium (VI) oxide systems. Copyright © 2004 John Wiley & Sons, Ltd.
Investigation of multiplet splitting of Fe 2p XPS spectra and bonding in iron compounds
Authors: Grosvenor A. P. , Kobe B. A. , Biesinger M. C. , McIntyre N. S.
Published: October 2004

Ferrous (Fe2+) and ferric (Fe3+) compounds were investigated by XPS to determine the usefulness of calculated multiplet peaks to fit high‐resolution iron 2p3/2 spectra from high‐spin compounds. The multiplets were found to fit most spectra well, particularly when contributions attributed to surface peaks and shake‐up satellites were included. This information was useful for fitting of the complex Fe 2p3/2 spectra for Fe3O4 where both Fe2+ and Fe3+ species are present. It was found that as the ionic bond character of the iron —ligand bond increased, the binding energy associated with either the ferrous or ferric 2p3/2 photoelectron peak also increased. This was determined to be due to the decrease in shielding of the iron cation by the more increasingly electronegative ligands. It was also observed that the difference in energy between a high‐spin iron 2p3/2 peak and its corresponding shake‐up satellite peak increased as the electronegativity of the ligand increased. The extrinsic loss spectra for ion oxides are also reported; these are as characteristic of each species as are the photoelectron peaks. Copyright © 2004 John Wiley & Sons, Ltd.
Unilateral ischemic sensorimotor cortical damage induces contralesional synaptogenesis and enhances skilled reaching with the ipsilateral forelimb in adult male rats
Authors: Luke Linslee M. , Allred Rachel P. , Jones Theresa A.
Published: October 2004

Unilateral damage to the forelimb representation area of the sensorimotor cortex (SMC) results in a compensatory reliance on the unimpaired (ipsilateral to the lesion) forelimb as well as reorganization of neuronal structure and connectivity in the contralateral motor cortex. Recently, male rats with unilateral electrolytic SMC lesions were found to have enhanced skilled reaching performance with the ipsilesional forelimb compared with sham‐operated controls. The present study was performed to determine whether these behavioral findings are replicable using an ischemic lesion and whether there is a link between the enhanced learning and synaptogenesis in motor cortical layer V opposite the trained limb and lesion, as assessed using stereological methods for light and electron microscopy. Rats were given a sham operation or an endothelin‐1 (ET‐1) induced ischemic SMC lesion. They were then trained for 20 days on a skilled reaching task with the unimpaired limb or received control procedures. As with previous findings using electrolytic lesions, rats with unilateral ischemic SMC lesions performed significantly better using the unimpaired forelimb than did sham‐operates. Lesions, but not training, significantly increased the total number of motor cortical layer V synapses per neuron as well as the number of perforated and multisynaptic bouton (MSB) synapses per neuron compared with shams. Thus, in addition to a net increase in synapses, the improved reaching ability was coupled with an increase in synapse subtypes that have previously been linked to enhanced synaptic efficacy. The failure to induce synaptogenesis in layer V with reach training alone is in contrast to previous findings and may be related to training intensity. Synapse 54:187–199, 2004. © 2004 Wiley‐Liss, Inc.
Alteration of hippocampal cell proliferation in mice lacking the β2 subunit of the neuronal nicotinic acetylcholine receptor
Authors: Harrist Alexia , Beech Robert D. , King Sarah L. , Zanardi Alessio , Cleary Muriel A. , Caldarone Barbara J. , Eisch Amelia , Zoli Michele , Picciotto Marina R.
Published: October 2004

Adult hippocampal neurogenesis declines with age in parallel with decreased performance on a variety of hippocampal‐dependent tasks. We measured the rate of cellular proliferation in the hippocampus of mice lacking the β2‐subunit of the nicotinic acetylcholine receptor (β2−/− mice) at three ages: young adult (3 months old), fully adult (7–10 months old), and aged (22–24 months old). Consistent with previous studies, we observed an age‐related decline in hippocampal proliferation in both groups. However, in fully adult β2−/− mice a 43% reduction of granule cell proliferation was detected compared to age‐matched controls. This was accompanied by a significant decrease in dentate gyrus area/section and the length of the granule cell layer in β2−/− mice. These alterations were not the result of a change in plasma corticosterone levels or expression of the neurotrophic factor BDNF in the dentate gyrus, two known regulators of hippocampal cell proliferation. Similarly, there was no increase in gliosis, abnormal myelination, or apoptotic cell death in the β2−/− animals, although there was a significant shift in the location of apoptotic cells in the dentate gyrus indicative of a change in neuronal survival. These results suggest that the β2‐subunit containing nicotinic acetylcholine receptors play an important role in regulating cell proliferation in the hippocampus and that endogenous acetylcholine may act to oppose the negative effects of normal aging and stress on cellular proliferation. Synapse 54:200–206, 2004. © 2004 Wiley‐Liss, Inc.
Inquiry in interaction: How local adaptations of curricula shape classroom communities
Authors: Enyedy Noel , Goldberg Jennifer
Published: October 2004

In this study, we seek a better understanding of how individuals and their daily interactions shape and reshape social structures that constitute a classroom community. Moreover, we provide insight into how discourse and classroom interactions shape the nature of a learning community, as well as which aspects of the classroom culture may be consequential for learning. The participants in this study include two teachers who are implementing a new environmental science program, Global Learning through Observation to Benefit the Environment (GLOBE), and interacting with 54 children in an urban middle school. Both qualitative and quantitative data are analyzed and presented. To gain a better understanding of the inquiry teaching within classroom communities, we compare and contrast the discourse and interactions of the two teachers during three parallel environmental science lessons. The focus of our analysis includes (1) how the community identifies the object or goal of its activity; and (2) how the rights, rules, and roles for members are established and inhabited in interaction. Quantitative analyses of student pre‐ and posttests suggest greater learning for students in one classroom over the other, providing support for the influence of the classroom community and interactional choices of the teacher on student learning. Implications of the findings from this study are discussed in the context of curricular design, professional development, and educational reform. ? 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 905‐935, 2004.
Premature adolescent autonomy: parent disengagement and deviant peer process in the amplification of problem behaviour
Authors: Dishion Thomas J. , Nelson Sarah E. , Bullock Bernadette Marie
Published: October 2004

Premature autonomy describes a developmental dynamic where parents of high‐risk adolescents reduce their involvement and guidance when confronted with challenges of problem behaviour and the influence of deviant friendships. This dynamic was tested on the sample of Oregon Youth Study boys (N=206), whose family management practices and friendships were observed on videotaped interaction tasks. Latent growth curve models were used to examine longitudinal trends between deviant friendship interactions and family management. Direct observations of deviant friendship process at age 14 were associated with degradation in family management during adolescence. A comparison of antisocial and well‐adjusted boys clarified that parents of antisocial boys (started early and persisted) decreased family management around puberty, in comparison to parents of well‐adjusted boys who maintained high levels of family management through adolescence. In predicting late adolescent problem behaviour, there was a statistically reliable interaction between family management degradation and deviant peer involvement in adolescence in support of the premature autonomy hypothesis. Adolescent males involved in deviant friendships, and whose parents decreased their family management, were most likely to use marijuana and commit antisocial acts at age 18. The implications for interventions that target adolescents are discussed.
“Very Important Persons” in adolescence: going beyond in‐school, single friendships in the study of peer homophily
Authors: Kiesner Jeff , Kerr Margaret , Stattin Håkan
Published: October 2004

Using a sample of 1227 Swedish adolescents we examined peer relations across contexts and for multiple peer targets (three “Very Important Persons”, VIPs). Specifically, we examined the relations between antisocial behaviour and the types of relationships individuals had with their VIPs (e.g. friend, romantic partner), the contexts in which they had met, and where they spent time (e.g. school, neighbourhood, club). Additionally, we tested an “additive homophily” hypothesis, or the idea that youths would show unique similarities to multiple peers. Results showed that individuals who nominated romantic partners as their first VIPs were the most antisocial (both boys and girls), and individuals who had met and spent time with their first VIPs in the neighbourhood were also the most antisocial. Similar results were found for the antisocial behaviour of the first VIP. Finally, results supported the additive homophily hypothesis, showing that significantly more variance in individual behaviour is explained when including second and third VIPs.
An LEA group 3 family member is involved in survival of C. elegans during exposure to stress
Authors: Gal Tali Z. , Glazer Itamar , Koltai Hinanit
Published: October 2004

In order to establish a functional role for late embryogenesis abundant (LEA) proteins in response to stress conditions in Caenorhabditis elegans, we silenced the expression of an LEA (Ce‐lea‐1) gene and determined the survival of worms under stress conditions. Ce‐lea‐1 transcription was induced during dehydration of C. elegans dauer juveniles. Following partial silencing of Ce‐lea‐1 transcription, we demonstrated a specific and significant reduction in worm survival during induction of desiccation, osmotic and heat stress. Together, these results establish a functional role for Ce‐lea‐1 in stress survival of C. elegans and suggest that Ce‐lea‐1 may function as a component that is common to the responses to the examined stress conditions.
Redox‐dependent modulation of the carrot SV channel by cytosolic pH
Authors: Scholz-Starke Joachim , Angeli Alexis De , Ferraretto Cristiana , Paluzzi Silvio , Gambale Franco , Carpaneto Armando
Published: October 2004

Currents mediated by a slow vacuolar (SV) channel were recorded and characterized in vacuoles from cultured carrot cells. The carrot channel shows the typical functional characteristics reported for channels of the SV category previously identified in other plants, i.e., slow voltage‐dependent activation kinetics, current activation favoured by cytosolic calcium and permeability to different monovalent cations. The carrot channel is strongly activated by cytosolic reducing agents (such as dithiothreitol, DTT, and glutathione, GSH) and has a peculiar dependence on cytosolic pH, which, in turn, is affected by the concentration of cytosolic reducing agents. Specifically, in 1 mM DTT or GSH the channel displayed a maximum conductance at neutral pH. The normalized conductance did not depend significantly on DTT concentration at acidic pH, while at alkaline pH the attenuation of the normalized conductance declines with increasing DTT concentration. Our results suggest two pH‐titratable groups within the carrot SV channel, one of these depending on cysteine residues exposed to the cytosolic side of the vacuole.
A flexible approach for understanding protein stability
Authors: Livesay D.R. , Dallakyan S. , Wood G.G. , Jacobs D.J.
Published: October 2004

A distance constraint model (DCM) is presented that identifies flexible regions within protein structure consistent with specified thermodynamic condition. The DCM is based on a rigorous free energy decomposition scheme representing structure as fluctuating constraint topologies. Entropy non‐additivity is problematic for naive decompositions, limiting the success of heat capacity predictions. The DCM resolves non‐additivity by summing over independent entropic components determined by an efficient network‐rigidity algorithm. A minimal 3‐parameter DCM is demonstrated to accurately reproduce experimental heat capacity curves. Free energy landscapes and quantitative stability‐flexibility relationships are obtained in terms of global flexibility. Several connections to experiment are made.
Heme binds to and inhibits the DNA‐binding activity of the global regulator FurA from Anabaena sp. PCC 7120
Authors: Hernández José A. , Peleato M.Luisa , Fillat Marı́a F. , Bes M.Teresa
Published: October 2004

Heme is an iron‐containing cofactor that aside from serving as the active group of essential proteins is a key element in the control of many molecular and cellular processes. In prokaryotes, the family of Fur (ferric uptake regulator) proteins governs processes essential for the survival of microorganims such as the iron homeostasis. We show that purified recombinant FurA from Anabaena sp. PCC 7120 interacts strongly with heme in the micromolar range and this interaction affects the in vitro ability of FurA to bind DNA, inhibiting that process in a concentration‐dependent fashion. Our results provide the first evidence of the possible involvement of heme in the regulatory function of cyanobacterial Fur.
Prädiktion von Ausbildungserfolg: Allgemeine Intelligenz (g) oder spezifische kognitive Fähigkeiten?
Authors: Schmidt-Atzert Lothar , Deter Bernhard , Jaeckel Silvia
Published: October 2004

Zusammenfassung. Die allgemeine Intelligenz ist Metaanalysen internationaler Untersuchungen zufolge der beste Prädiktor von Ausbildungserfolg, und spezifische kognitive Fähigkeiten klären darüber hinaus kaum noch zusätzliche Varianz auf. Die vorliegende Untersuchung sollte klären, ob diese Befunde auf das deutsche Ausbildungssystem übertragen werden können. Insgesamt N = 646 Auszubildende aus vier technischen Berufen und zwei Büroberufen in der chemischen Industrie wurden vor Beginn ihrer Ausbildung mit dem Wilde-Intelligenz-Test von Jäger und Althoff (1983 ) sowie mit weiteren kognitiven Leistungstests untersucht. Die allgemeine Intelligenz erwies sich mit Ausnahme eines Berufs als bester Prädiktor für das Ergebnis in der theoretischen Abschlussprüfung ca. vier Jahre später mit einer durchschnittlichen Validität von r = .69 (nach Korrektur für Varianzeinschränkung). Von den fünf kognitiven Fähigkeiten nach Thurstone leistete nur eine bei einem Beruf einen zusätzlichen signifikanten Beitrag. Inkrementelle Validität zeigte ein Technischer-Verständnis-Test, der bei drei technischen Berufen zusätzlich 3-7 Prozent Varianz aufklärte. Es wird gefolgert, dass eine Kombination von allgemeiner Intelligenz und berufsspezifischem Vorwissen am besten geeignet ist, Ausbildungserfolg vorherzusagen.
Complex lithospheric structure under the central Baltic Shield from surface wave tomography
Authors: Bruneton Marianne , Pedersen Helle A. , Farra Véronique , Arndt Nicholas T. , Vacher Pierre , Achauer U. , Alinaghi A. , Ansorge J. , Bock G. , Friederich W. , Grad M. , Guterch A. , Heikkinen P. , Hjelt S.‐E. , Hyvönen T. L. , Ikonen J.‐P. , Kissling E. , Komminaho K. , Korja A. , Kozlovskaya E. , Nevsky M. V. , Paulssen H. , Pavlenkova N. I. , Plomerová J. , Raita T. , Riznichenko O. Y. , Roberts R. G. , Sandoval S. , Sanina I. A. , Sharov N. V. , Shomali Z. H. , Tiikkainen J. , Wielandt E. , Wilegalla K. , Yliniemi J. , Yurov Y. G.
Published: October 2004

Regional seismic tomography provides valuable information on the structure of shields, thereby gaining insight to the formation and stabilization of old continents. Fennoscandia (known as the Baltic Shield for its exposed part) is a composite shield for which the last recorded tectonic event is the intrusion of the Rapakivi granitoids around 1.6 Ga. A seismic experiment carried out as part of the European project Svecofennian‐Karelia‐Lapland‐Kola (SVEKALAPKO) was designed to study the upper mantle of the Finnish part of the Baltic Shield, especially the boundary between Archean and Proterozoic domains. We invert the fundamental mode Rayleigh waves to obtain a three‐dimensional shear wave velocity model using a ray‐based method accounting for the curvature of wave fronts. The experiment geometry allows an evaluation of lateral variations in velocities down to 150 km depth. The obtained model exhibits variations of up to ±3% in S wave velocities. As the thermal variations beneath Finland are very small, these lateral variations must be caused by different rock compositions. The lithospheres beneath the Archean and Proterozoic domains are not noticeably different in the S wave velocity maps. A classification of the velocity profiles with depth yields four main families and five intermediate regions that can be correlated with surface features. The comparison of these profiles with composition‐based shear wave velocities implies both lateral and vertical variations of the mineralogy.
Optimal multiproxy reconstruction of sea surface temperature from corals
Authors: Solow Andrew , Huppert Amit
Published: October 2004

Past sea surface temperatures have been reconstructed using coral measurements of single geochemical proxies. There is some interest in improving reconstruction by combining results from different proxies. The construction of the optimal multiproxy reconstruction is described. The approach is illustrated using some data from New Caledonia.
Faster technique for the modal analysis of a coaxial cable with misaligned inner conductor
Authors: Gesmundo Attilio , Vaccaro Vittorio G. , Guglielmi Marco
Published: October 2004

In this article we present a new technique for the modal analysis of a coaxial conductor with misaligned inner rod. The value of this method lies in the fact that, being based on linear techniques, it is possible to achieve the cutoff frequencies of the propagating modes without losing precision when the order of the modes increases. The differences in the results, obtained using 225 and 1600 basis functions, is quite negligible. Moreover, the procedure is completely analytical up to the evaluation of projection integrals, and the numerical part is restricted only to the matrix inversion. Therefore the run time needed is very low. This method was implemented in Fortran software written on this purpose by the authors. Numerical results are presented, keeping into account the computational time and complexity, and finally showing good agreement with other results already present in literature.
Coastal uplift and thrust faulting associated with the Mw = 6.8 Zemmouri (Algeria) earthquake of 21 May, 2003
Authors: Meghraoui M. , Maouche S. , Chemaa B. , Cakir Z. , Aoudia A. , Harbi A. , Alasset P.‐J. , Ayadi A. , Bouhadad Y. , Benhamouda F.
Published: October 2004

A shoreline uplift marked by a continuous white band visible at rocky headlands occurred during the 21 May 2003 earthquake (Mw 6.8) in northern Algeria. We measured the amount of coastal uplift on a white band (emerged algae) and harbors quays between Boumerdes and Dellys. Most of measured points were collected using tape and differential GPS on rocky headlands with σ ± 0.15 m error bar (tidal prism). Leveling lines running parallel and orthogonal to the coast also provide the precise amount of uplift in the epicentral area. The uplift distribution shows an average 0.55 m along the shoreline with a maximum 0.75 m east of Boumerdes and a minimum close to 0 near Cap Djinet. The active deformation related to a thrust fault is modeled along the ∼55 km coastline. The dislocation model predicts surface slip on a N 54°E trending reverse fault, dipping 50° SE in agreement with CMT solution and coastal uplift. The faulting characteristics imply a fault geometry with possible sea bottom ruptures between 5 to 10 km offshore.
Cluster observations of complex 3D magnetic structures at the magnetopause
Authors: Louarn P. , Fedorov A. , Budnik E. , Fruit G. , Sauvaud J. A. , Harvey C. C. , Dandouras I. , Rème H. , Dunlop M. C. , Balogh A.
Published: October 2004

On June 30, 2001, around 0530 UT, Cluster was moving along the magnetopause with spacecraft on both sides of the discontinuity. The configuration was ‘quasi‐ideal’ with magnetic field and plasma flow almost aligned in the magnetosheath and nearly anti‐parallel to the magnetospheric field. Cluster observed several perturbations with leading and trailing edges corresponding respectively to tangential and rotational discontinuities. They present a complex 3D topology, consistent with the inter‐linking of flux tubes resulting from reconnections occurring at different sites.
Drifting Arctic sea ice archives changes in ocean surface conditions
Authors: Pfirman Stephanie , Haxby William , Eicken Hajo , Jeffries Martin , Bauch Dorothea
Published: October 2004

δ18O profiles in drifting Arctic sea ice are coupled with back trajectories of ice drift and an ice growth model to reconstruct the surface hydrography of the Arctic Ocean interior. The results compare well with δ18O values obtained by traditional oceanographic methods and known water mass distributions. Analysis of the stable isotopic composition of sea ice floes sampled at strategic and relatively accessible locations, e.g., Fram Strait, could aid in mapping spatial and temporal variations in Arctic Ocean surface waters.
Fire at Iraqi sulfur plant emits SO2 clouds detected by Earth Probe TOMS
Authors: Carn S. A. , Krueger A. J. , Krotkov N. A. , Gray M. A.
Published: October 2004

A fire started at the Al‐Mishraq State Sulfur plant near Mosul, Iraq on 24 June 2003 and burned for almost a month. Combustion of elemental sulfur in the fire produced dense clouds of sulfur dioxide (SO2) that were detected from space by the Earth Probe Total Ozone Mapping Spectrometer (EP TOMS) on 18 days. Estimated daily SO2 production from the continuously emitting source closely mirrors contemporaneous thermal infrared radiance from the fire sensed in the 3.96 μm band of the Moderate Resolution Imaging Spectroradiometer (MODIS). We calculate total SO2 production during the blaze amounting to ∼600 kilotons, which is roughly commensurate with the predicted SO2 yield from the inventory of elemental sulfur allegedly destroyed by the fire when potential SO2 losses are considered. This event is the largest non‐volcanic SO2 emission incident measured to date by any TOMS instrument.
Evidence for O‐atom exchange in the O(1D) + N2O reaction as the source of mass‐independent isotopic fractionation in atmospheric N2O
Authors: Yung Yuk L. , Liang Mao‐Chang , Blake Geoffrey A. , Muller Richard P. , Miller Charles E.
Published: October 2004

Recent experiments have shown that in the oxygen isotopic exchange reaction for O(1D) + CO2 the elastic channel is approximately 50% that of the inelastic channel [Perri et al., 2003]. We propose an analogous oxygen atom exchange reaction for the isoelectronic O(1D) + N2O system to explain the mass‐independent isotopic fractionation (MIF) in atmospheric N2O. We apply quantum chemical methods to compute the energetics of the potential energy surfaces on which the O(1D) + N2O reaction occurs. Preliminary modeling results indicate that oxygen isotopic exchange via O(1D) + N2O can account for the MIF oxygen anomaly if the oxygen atom isotopic exchange rate is 30–50% that of the total rate for the reactive channels.
Stormtime subauroral density troughs: Ion‐molecule kinetics effects
Authors: Mishin E. V. , Burke W. J. , Viggiano A. A.
Published: October 2004

We report on subauroral plasma density troughs observed by Defense Meteorological Satellite Program (DMSP) satellites during the major magnetic storm of 6 April 2000. The troughs were embedded within strongly irregular, ≥500‐km wide subauroral convection streams, composed of two distinctive parts. The poleward part coincided with strong wave structures, energetic (ring current) ion precipitations, and enhanced vertical ion flows. One or several narrow density decreases were present here. The equatorward part was marked by a density trough coincident with a local maximum of the electron temperature ∼7000–9000 K. Here the ion temperatures and downward vertical ion velocities were ∼2000 K and <20 m/s, respectively. The mean convection velocity was typically ≤500 m/s. We develop analytical approximations for the rate coefficients of the charge exchange reactions based on recent laboratory experiments. These have been used in local modeling of the equatorward F peak density depletions. Topside steady‐state density profiles were evaluated assuming diffusive equilibrium in a given Te profile. A scenario for the transition of an initial density‐height profile to a flat profile is described. Substantial agreement between the modeling results and DMSP observations indicates that the vibrational mechanism contributes significantly to the formation of high‐Te‐related density troughs.
On the ‘Efficient Boundaries of the State’: The Contribution of Transaction-Costs Economics to the Analysis of Decentralization and Devolution in Natural Resource Management
Authors: Birner Regina , Wittmer Heidi
Published: October 2004

Decentralization and devolution—also referred to as ‘rolling back the boundaries of the state’—are important policy trends in natural resource management. Drawing a parallel with the efficient-boundary problem in industrial organization, the authors show how transaction-costs economics can be applied to identify the efficient boundaries of the state in natural resource management. The following extensions of the transaction-cost framework are proposed: (1) introduction of care intensity and contest intensity as additional key attributes of transactions; (2) introduction of cooperative types of organization as a third governance structure besides market and hierarchies; and (3) introduction of natural resource characteristics, social capital, and state capability as contextual variables. The authors also discuss the possibilities for empirical application.
Just the Usual Suspects? Partnerships and Environmental Regulation
Authors: Sherlock Kirsty L , Kirk Elizabeth A , Reeves Alison D
Published: October 2004

Governance based on partnerships has become a characteristic of late capitalist societies. This paper explores how this new collaborative approach to environmental regulation creates challenges for existing technocratic policy networks, drawing on an organisational ethnography of the Scottish Environment Protection Agency. Our findings suggest partnership working is embraced for four reasons—to improve understanding of problems, to develop resource-efficient management solutions, to improve implementation of these solutions, and to improve communication and trust within the policy network. However, there appear to be three areas of difficulty. First, decisionmaking appears to be dominated by technocratic public servants; second, practical reasons for partnership, rather than embracing the normative arguments for discursive democracy, motivate most participants; and, third, participants are yet to experience the benefits of partnerships. We suggest three key areas which might address these problems and contribute towards a more successful implementation of the collaborative approach to regulation, namely to provide incentives for partnership working (demonstrating how the perceived benefits outweigh costs), developing interorganisational trust and providing organisational support (resources). We conclude with an analysis of the constraints that must be overcome to develop effective partnerships for environmental management, particularly the need to extend the network beyond the ‘usual suspects' and to embrace the normative dimensions of participatory democracy.
The Short-Term and Long-Term Ramifications of Linkages Involving Natural Resources: The US – Mexico Transboundary Water Case
Authors: Fischhendler Itay , Feitelson Eran , Eaton David
Published: October 2004

Issue linkage is often recommended as a strategy for enhancing cooperation. Lately it has been suggested that this strategy could also be applied to the management of transboundary natural resources. The authors examine the viability of this suggestion. They argue that in the case of natural resources such a linkage may have both short-term and long-term implications. Essentially, by constraining the options available to the various parties, such linkages limit ability to adapt management regimes to changes in the environment; thereby, they limit the ability to address environmental stresses and crises. These negative implications may be redressed by mechanisms that will allow the parties to adapt the linkage to new conditions and by tactics that reduce the political cost of a linkage strategy. The authors focus on the negotiation process concerning US–Mexico transboundary water, which was based on a long-term spatial linkage combining the waters of the Colorado River and those of the Rio Grande. This spatial linkage was advanced by a short-term issue linkage, in which the Mexican government supported the establishment of the United Nations in return for the US federal government's willingness to accept the spatial linkage. These linkages were found to have both short-term and long-term adverse implications. The short-term implications were delays in negotiations, inconsistency in the legal doctrines held by the different parties during the negotiation, and a threat to sovereignty. The main long-term implication identified is the current inability of Mexico to adapt the linkage in response to the ten-year drought along the Rio Grande, as manifest in the inability of Mexico to meet its water obligations to the USA along the Rio Grande. This has resulted in a controversy between Mexico and the USA, and between the Mexican federal government and the Mexican border states. It is suggested that flexibility provisions be included when linkages involving natural resources are advanced, so that the necessary adaptations in regimes management will be allowed for without necessitating a renegotiation of the treaty.
Determination of Inorganic Selenium Species in Marine Waters by Hydride Generation - AFS
Authors: Wake Bronwyn D. , Butler Edward C. V. , Featherstone Alison M. , Virtue Patti , Averty Bernard , Michel Pierre
Published: October 2004

A method based on hydride generation with cryogenic trapping and atomic fluorescence detection was developed that is capable of determining both inorganic Se species (SeIV and SeVI) while at sea. Evaluation of the system for optimal performance was made for each stage of the analysis and detection sequence, as well as for the SeVI reduction step. A detection limit of 0.4 ng L−1 Se in a 10 mL sample was achieved using this method. Precision was better than 3.5% for 25, 100, and 1000 ng L−1 SeIV standard solutions. Accuracy was determined by recovery studies using natural samples and a certified reference seawater (NASS-5).
Measurements of Lead Complexation with Organic Ligands using DGT
Authors: Scally Shaun , Zhang Hao , Davison William
Published: October 2004

The technique of diffusive gradients in thin films (DGT) was used to investigate the distribution of Pb between inorganic forms and organic complexes in various solutions that contained fulvic acid, humic acid, or nitrilotriacetic acid (NTA) over the pH range 4–8. Three types of DGT devices with diffusive gels of different pore sizes were used. When the diffusion coefficient of each species in each gel type was considered, the DGT measurements obtained agreed well with the distribution of species predicted by the ECOSAT equilibrium speciation model for all solutions and gel types. When an appreciable proportion of inorganic species was present in solution, direct measurements by DGT using the most restricted gel provided a reasonable estimate of the inorganic species in solution. This demonstrates that DGT is able to use differences in molecule mobility to distinguish between species in solution.
Metal Mobilization from Complex Sulfide Ore Concentrate: Effect of Light and pH
Authors: Tsang Jeffrey J. , Parry David L.
Published: October 2004

The aim of this study was to determine the influence of photo-irradiation and pH on the mobilization of metals from a complex sulfide ore concentrate containing known semiconductors (PbS, ZnS, CdS, FeS2, and CuFeS2). The mobilization of Zn, Fe, and Cd increased under illumination, which is attributed to the semiconductor nature of ZnS, FeS2, and CdS, respectively. An increase in mobilization of Zn, Fe, and Cd under light is observed with decreasing pH, because of increased surface protonation and the greater oxidizing property of photoholes. The semiconductor nature of PbS and CuFeS2 is observed at pH 2. However, at higher pH the concentrations of mobilized Pb and Cu are greater in darkness than under illumination. This is attributed to the light enhanced exchange reactions involving dissolved Pb and Cu with metal sulfides more soluble than PbS and CuS.
Arsenic Species Determination in Biological Tissues by HPLC - ICP - MS and HPLC - HG - ICP - MS
Authors: Kirby Jason , Maher William , Ellwood Michael , Krikowa Frank
Published: October 2004

The use of high-pressure liquid chromatography coupled directly or by a hydride generation system to an inductively coupled plasma mass spectrometer for the unambiguous measurement of 13 arsenic species in marine biological extracts is described. The use of two chromatography systems; a Supelcosil LC-SCX cation-exchange column eluted with a 20 mM pyridine mobile phase adjusted to pH 2.2 and 2.6 with formic acid, with a flow rate of 1.5 mL min−1 at 40°C, and a Hamilton PRP-X100 anion-exchange column eluted with 20 mM NH4H2PO4 buffer at pH 5.6, with a flow rate of 1.5 mL min−1 at 40°C, was required to separate and quantify cation and anion arsenic species. Under these conditions, arsenous acid could not be separated from other arsenic species and required the use of an additional hydride generation step. Arsenic species concentrations in a locally available Tasmanian kelp (Durvillea potatorum), a certified reference material (DORM-2), and a range of commercially available macroalgae supplements and sushi seaweeds have been measured and are provided for use as in-house quality control samples to assess the effectiveness of sample preparation, extraction, and measurement techniques.
Ciona intestinalis
Hox gene cluster: Its dispersed structure and residual colinear expression in development
Authors: Ikuta Tetsuro , Yoshida Natsue , Satoh Nori , Saiga Hidetoshi
Published: October 2004

Ascidians, belonging to the subphylum Urochordata, the earliest branch from the lineage to the vertebrates, exhibit a prototypical morphogenesis of chordates in the larval development, although they subsequently metamorphose into adults with a unique body structure. Recent draft genome analysis of the ascidian
Ciona intestinalis
has identified 9 Hox genes, which, however, have been located on five scaffolds. Similarly, expression patterns of
Ciona
Hox genes are largely unknown, although some data have been available for a few Hox member genes. Thus, the cluster structure and colinearity of Hox genes are still an enigma in
C. intestinalis
. To address these issues, we used fluorescence
in situ
hybridization and whole-mount
in situ
hybridization techniques and examined the genomic organization and spatiotemporal expression of all Hox as well as extended Hox member genes (Evx and Mox) of
C. intestinalis
. We found that seven of nine
Ciona
Hox genes are located on a single chromosome with some ordering exceptions, and the other genes, including Evx and Mox, are located on three other chromosomes. Some
Ciona
Hox genes, if not all, exhibited spatially coordinated expression within the larval central nervous system and the gut of the juvenile. In light of these observations, we suggest that the cluster organization and colinearity of the Hox genes are under dispersing and disintegrating conditions in
C. intestinalis
.
Three-body interactions improve the prediction of rate and mechanism in protein folding models
Authors: Ejtehadi M. R. , Avall S. P. , Plotkin S. S.
Published: October 2004

Here we study the effects of many-body interactions on rate and mechanism in protein folding by using the results of molecular dynamics simulations on numerous coarse-grained C
α
-model single-domain proteins. After adding three-body interactions explicitly as a perturbation to a Gō -like Hamiltonian with native pairwise interactions only, we have found (
i
) a significantly increased correlation with experimental φ values and folding rates, (
ii
) a stronger correlation of folding rate with contact order, matching the experimental range in rates when the fraction of three-body energy in the native state is ≈20%, and (
iii
) a considerably larger amount of three-body energy present in chymotripsin inhibitor than in the other proteins studied.
Wolbachia-induced cytoplasmic incompatibility as a means for insect pest population control
Authors: Zabalou Sofia , Riegler Markus , Theodorakopoulou Marianna , Stauffer Christian , Savakis Charalambos , Bourtzis Kostas
Published: October 2004

Biological control is the purposeful introduction of parasites, predators, and pathogens to reduce or suppress pest populations.Wolbachiaare inherited bacteria of arthropods that have recently attracted attention for their potential as new biocontrol agents.Wolbachiamanipulate host reproduction by using several strategies, one of which is cytoplasmic incompatibility (CI) [Stouthamer, R., Breeuwer, J. A. J. & Hurst, G. D. D. (1999)Annu. Rev. Microbiol.53, 71–102]. We establishedWolbachia-infected lines of the medflyCeratitis capitatausing the infected cherry fruit flyRhagoletis cerasias donor.Wolbachiainduced complete CI in the novel host. Laboratory cage populations were completely suppressed by single releases of infected males, suggesting thatWolbachia-induced CI could be used as a novel environmentally friendly tool for the control of medfly populations. The results also encourage the introduction ofWolbachiainto pest and vector species of economic and hygenic relevance to suppress or modify natural populations.
Development of a polyclonal antiserum for the detection of the isoforms of the receptors for human growth hormone-releasing hormone on tumors
Authors: Toller Gabor L. , Horvath Judit E. , Schally Andrew V. , Halmos Gabor , Varga Jozsef L. , Groot Kate , Chism David , Zarandi Marta
Published: October 2004

Antagonists of growth hormone-releasing hormone (GHRH) inhibit the growth of various human cancers by multiple mechanisms, which include direct effects on tumor cells through the splice variants (SV) of the GHRH receptor. Our findings suggest that the tumoral protein encoded by SV 1 (SV1) is a likely functional receptor. The aim of this study was to develop a polyclonal antiserum against a polypeptide analog of segment 1-25 of the putative SV1receptor protein. Rabbits were immunized with [Ala-23]SV1(1-25)-Tyr-26-Cys-27-NH2as a hapten, conjugated to BSA or keyhole limpet hemocyanin. The antisera thus generated were evaluated by RIA for binding to the radiolabeled hapten. The specificity and sensitivity of the antisera were studied on xenografts of RL and HT human non-Hodgkin's lymphomas. The sera raised against keyhole limpet hemocyanin-SV1hapten, showed binding values of 50-75% at a 1:56,000 dilution. In Western blot analyses, the purified polyclonal antibody recognized a specific signal with a molecular mass of ≈40 kDa in RL and HT lymphomas. This band corresponds to the estimated molecular mass of the GHRH receptor isoform encoded by SV1. RT-PCR and ligand binding studies also revealed the expression of SV1and the presence of high-affinity binding sites for GHRH on RL and HT tumors. Because the antiserum developed recognizes the tumoral GHRH receptor protein encoded by SV1, it should be of value in various investigations.
RNA polymerase can track a DNA groove during promoter search
Authors: Sakata-Sogawa Kumiko , Shimamoto Nobuo
Published: October 2004

Many proteins select special DNA sequences to form functional complexes. In one possible mechanism, protein molecules would scan DNA sequences by tracking a groove without complete dissociation. Upon dragging single molecules of DNA over a surface carrying fixed
Escherichia coli
RNA polymerase holoenzyme, we detected rotation of individual DNA molecules, providing direct evidence that a DNA-binding protein can track a DNA groove. These results confirm our previous observations of longitudinal movement of RNA polymerase along fixed, extended DNA and, moreover, imply that groove tracking facilitates scanning of DNA sequences.
The
Caenorhabditis elegans
IMPAS gene, imp-2, is essential for development and is functionally distinct from related presenilins
Authors: Grigorenko Anastasia P. , Moliaka Yuri K. , Soto Martha C. , Mello Craig C. , Rogaev Evgeny I.
Published: October 2004

Presenilins (PSs) are required for Notch signaling in the development of vertebrates and invertebrates. Mutations in human PS1 and PS2 homologs are a cause of familial Alzheimer's disease (AD). The function of the recently identified ancient family of IMPAS proteins (IMP/SPP/PSH) homologous to PSs is not yet known. We show here that, unlike PSs, IMPs (orthologous
C. elegans Ce-imp-2
and human hIMP1/SPP) do not promote Notch (
C. elegans lin-12,glp-1
) proteolysis or signaling. The knock-down of
Ce-imp-2
leads to embryonic death and an abnormal molting phenotype in
Caenorhabditis elegans
. The molting defect induced by
Ce-imp-2
deficiency was mimicked by depleting cholesterol or disrupting
Ce-lrp-1
and suppressed, in part, by expression of the
Ce-lrp-1
derivate.
C. elegans lrp-1
is a homolog of mammalian megalin, lipoprotein receptor-related protein (LRP) receptors essential for cholesterol and lipoprotein endocytosis and signaling. These data suggest that IMPs are functionally distinct from related PSs and implicate IMPs as critical regulators of development that may potentially interact with the lipid-lipoprotein receptor-mediated pathway.
Targeting a binding pocket within the trimer-of-hairpins: Small-molecule inhibition of viral fusion
Authors: Cianci Christopher , Langley David R. , Dischino Douglas D. , Sun Yaxiong , Yu Kuo-Long , Stanley Anne , Roach Julia , Li Zhufang , Dalterio Richard , Colonno Richard , Meanwell Nicholas A. , Krystal Mark
Published: October 2004

Trimeric class I virus fusion proteins undergo a series of conformational rearrangements that leads to the association of C- and N-terminal heptad repeat domains in a “trimer-of-hairpins” structure, facilitating the apposition of viral and cellular membranes during fusion. This final fusion hairpin structure is sustained by protein–protein interactions, associations thought initially to be refractory to small-molecule inhibition because of the large surface area involved. By using a photoaffinity analog of a potent respiratory syncytial virus fusion inhibitor, we directly probed the interaction of the inhibitor with its fusion protein target. Studies have shown that these inhibitors bind within a hydrophobic cavity formed on the surface of the N-terminal heptad-repeat trimer. In the fusogenic state, this pocket is occupied by key amino acid residues from the C-terminal heptad repeat that stabilize the trimer-of-hairpins structure. The results indicate that a low-molecular-weight fusion inhibitor can interfere with the formation or consolidation of key structures within the hairpin moiety that are essential for membrane fusion. Because analogous cavities are present in many class I viruses, including HIV, these results demonstrate the feasibility of this approach as a strategy for drug discovery.
Bioavailability of angiotensin I converting enzyme inhibitory peptides
Authors: Vermeirssen Vanessa , Camp John Van , Verstraete Willy
Published: October 2004

Hypertension or high blood pressure is a significant health problem worldwide. Bioactive peptides that inhibit angiotensin I converting enzyme (ACE) in the cardiovascular system can contribute to the prevention and treatment of hypertension. These ACE inhibitory peptides are derived from many food proteins, especially milk proteins. An ACE inhibitory activityin vitrodoes not always imply an antihypertensive effectin vivo. Even if it does, it is very difficult to establish a direct relationship betweenin vitroandin vivoactivity. This is mainly due to the bioavailability of the ACE inhibitory peptides after oral administration and the fact that peptides may influence blood pressure by mechanisms other than ACE inhibition. To exert an antihypertensive effect after oral ingestion, ACE inhibitory peptides have to reach the cardiovascular system in an active form. Therefore, they need to remain active during digestion by human proteases and be transported through the intestinal wall into the blood. The bioavailability of some ACE inhibitory peptides has been studied. It is also known that (hydroxy)proline-containing peptides are generally resistant to degradation by digestive enzymes. Peptides can be absorbed intact through the intestine by paracellular and transcellular routes, but the potency of the bioactivity after absorption is inversely correlated to chain length. In addition, some strategies are proposed to increase the bioavailability of ACE inhibitory peptides. Further research into the bioavailability of ACE inhibitory peptides will lead to the development of more effective ACE inhibitory peptides and foods.