bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the complex thermal behavior of poly(L‐lactic acid) film. II. Samples crystallized from the melt
Authors: Ling Xiaoyun , Spruiell Joseph E.
Published: October 2006

The complex thermal behavior of poly(l‐lactic acid) films crystallized from the melt, either isothermally or nonisothermally, was studied by differential scanning calorimetry (DSC), wide angle X‐ray diffraction, and small angle X‐ray scattering. The variation of the thermal behavior with crystallization temperature, time, and cooling rate was documented and analyzed. After nonisothermal crystallization at low cooling rates that develop high crystallinity, an obvious double melting peak appears at modest heating rates (e.g., 10 °C/min). At higher heating rates, these samples exhibit only single melting. However, an unusual form of double melting occurs under the majority of the conditions studied under either isothermal or nonisothermal conditions. In this case, double melting is marked by the appearance of a recrystallization exotherm just prior to the final melting that obscures the observation of the melting of the crystals formed during the initial crystallization process. The occurrence of double melting in melt‐crystallized samples was concluded to be the result of a melt‐recrystallization process occurring during the subsequent DSC heating scan; it is a function of crystalline perfection, not the initial crystallinity, nor whether or not the crystallization reached completion at the crystallization temperature. Many other very interesting observations are also discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3378–3391, 2006
Harmonised pesticide risk trend indicator for food (HAPERITIF): the methodological approach
Authors: Calliera Maura , Finizio Antonio , Azimonti Giovanna , Benfenati Emilio , Trevisan Marco
Published: October 2006

To provide a harmonised European approach for pesticide risk indicators, the Sixth EU Framework Programme recently financed the HAIR (HArmonised environmental Indicators for pesticide Risk) project. This paper illustrates the methodology underlying a new indicator—HAPERITIF (HArmonised PEsticide RIsk Trend Indicator for Food), developed in HAIR, for tracking acute and chronic pesticide risk trends for consumers. The acute indicator, HAPERITIFac, is based on the ratio between an estimated short‐term intake (ESTI), calculated as recommended by the World Health Organisation (WHO), and the acute reference dose (ARfD); the chronic indicator HAPERITIFchr is based on the ratio between an estimated daily intake (EDI) and the admissible daily intake (ADI). HAPERITIF can be applied at different levels of aggregation. Each level gives information for proper risk management of pesticides to reduce the risk associated with food consumption. An example of application using realistic scenarios of pesticide treatments on a potato crop in central‐northern Italy is reported to illustrate the different steps of HAPERITIF. Copyright © 2006 Society of Chemical Industry
Synergistic effect of heartwood extractives and quaternary ammonium compounds on termite resistance of treated wood
Authors: Hwang Won‐Joung , Kartal S Nami , Yoshimura Tsuyoshi , Imamura Yuji
Published: October 2006

This study evaluates the synergistic effect of wood extractives and quaternary ammonium compounds (QACs) on the resistance to termites of several treated wood species. Wood specimens from different natural durability classes were extracted with either hot water alone or hot water + ethanol/benzene. The extracted and unextracted wood specimens were treated with either didecyldimethylammonium tetrafluoroborate (DBF) or commercial didecyldimethylammonium chloride (DDAC) solutions and then exposed to subterranean termites, Coptotermes formosanus Shiraki, for 3 weeks under laboratory conditions. The results showed that extractives of the heartwood portions of the wood species contributed to increased resistance against termite attack in the presence of either DBF or DDAC wood preservatives. The synergistic effect of wood extractives and DBF was much clearer with Pseudotsuga menziesii (Mirbel) Franco and Tsuga heterophylla Sarg wood samples. Further studies are needed for a better understanding of the synergism between wood extractives and either DBF or DDAC using both the sapwood and heartwood portions of the same wood species. Copyright © 2006 Society of Chemical Industry
Internal friction peak associated with the ordering process in B2 FeAl alloys
Authors: Wu J. , Han F. S. , Hao G. L. , Wang Q. Z. , Gao Z. Y.
Published: October 2006

The internal friction behaviors of B2 FeAl alloys were examined to understand the correlation between the ordering and the movement of the atomic defects. A new internal friction peak was found at around 540 °C and 570 °C in the oil‐quenched Fe57Al43 and Fe47Al53 alloys, respectively, while in the furnace‐cooled specimens, the peak disappeared. The peak has the typical phase transition characters, and it is suggested that the peak probably originates from the elevation of the degree of order, which is caused by the jump of antisite atoms to their own sublattice sites by means of the nearest neighboring vacancies. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Desorption electrospray ionization using an Orbitrap mass spectrometer: exact mass measurements on drugs and peptides
Authors: Hu Qizhi , Talaty Nari , Noll Robert J. , Cooks R. Graham
Published: October 2006

Desorption electrospray ionization (DESI) is implemented on an Orbitrap mass spectrometer. The ion source is described and applications which utilize the high‐resolution capabilities of the Orbitrap are emphasized, including the characterization of peptides and active ingredients in pharmaceutical tablets. Measurements are made in less than 1 s at a resolution of 60 000. The implications of the data for the mechanisms of DESI are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Cost detectability and stability of adaptive control systems
Authors: Wang R. , Paul A. , Stefanovic M. , Safonov M. G.
Published: October 2006

Hysteresis switching adaptive control systems designed using certain types of 𝔏2𝔢‐gain‐type cost functions are shown to be robustly stabilizing if and only if certain plant‐independent conditions are satisfied by the candidate controllers. These properties ensure closed‐loop stability for the switched multicontroller adaptive control (MCAC) system whenever stabilization is feasible. The result is asafe adaptive control system, which has the property that closing the adaptive loop can never induce instability provided only that at least one of the candidate controllers is capable of stabilizing the plant. Copyright © 2006 John Wiley & Sons, Ltd.
Tree‐structured gatekeeping tests in clinical trials with hierarchically ordered multiple objectives
Authors: Dmitrienko Alex , Wiens Brian L. , Tamhane Ajit C. , Wang Xin
Published: October 2006

This paper discusses a new class of multiple testing procedures, tree‐structured gatekeeping procedures, with clinical trial applications. These procedures arise in clinical trials with hierarchically ordered multiple objectives, for example, in the context of multiple dose–control tests with logical restrictions or analysis of multiple endpoints. The proposed approach is based on the principle of closed testing and generalizes the serial and parallel gatekeeping approaches developed by Westfall and Krishen (J. Statist. Planning Infer. 2001; 99:25–41) and Dmitrienko et al. (Statist. Med. 2003; 22:2387–2400). The proposed testing methodology is illustrated using a clinical trial with multiple endpoints (primary, secondary and tertiary) and multiple objectives (superiority and non‐inferiority testing) as well as a dose‐finding trial with multiple endpoints. Copyright © 2006 John Wiley & Sons, Ltd.
Tissue inhibitor of metalloproteinase‐2 (TIMP‐2) location in the ventral, lateral, dorsal and anterior lobes of rat prostate by immunohistochemistry
Authors: Delella Flávia K. , Justulin Luis A. , Felisbino Sérgio L.
Published: October 2006

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a major role in extracellular matrix component degradation in several normal and abnormal tissue situations; they are also found in human seminal plasma. MMPs have been found in rat prostate secretions and are nearly lobe specific in expression pattern. The aim of this study was to evaluate whether TIMP‐2, like other semen components, is expressed differently from different rat prostatic lobes. Immunohistochemical staining was performed in both young and adult rat ventral (VP), lateral (LP), dorsal (DP), and anterior (AP) prostatic lobes and confirmed by western blotting. TIMP‐2 expression was found in the epithelial cells in the following sequence: LP > AP > DP > VP, in both young and adult rats. In this study, 100% of adult LP presented histological signs of prostatitis, where TIMP‐2 immunostaining was positive in normal epithelium even with intraluminal neutrophils, but was reduced or absent in the epithelium with intraepithelial leukocytes or with periductal stroma disorganization associated with mononuclear cell infiltration. However, TIMP‐2 expression in LP was not induced by prostatitis, since younger rat LPs were also strongly TIMP‐2 positive. The distal and intermediate VP regions were TIMP‐2 negative, but the proximal regions were strongly stained. Western blotting results confirmed the high TIMP‐2 expression in the LP lobe. Thus, TIMP‐2 is expressed differently between the prostatic lobes and is another nearly lobe‐specific protein, which plays a role in the regulation of MMP activity in seminal plasma and glandular homeostasis. TIMP‐2 is also another regional ductal variation of VP. Further studies should address whether TIMP‐2 expression is related to the highest incidence of rat LP prostatitis and adenocarcinoma.
Inhibition of MMP‐2 activation and release as a novel mechanism for HDL‐induced cardioprotection
Authors: Bellosta Stefano , Gomaraschi Monica , Canavesi Monica , Rossoni Giuseppe , Monetti Mara , Franceschini Guido , Calabresi Laura
Published: October 2006

High density lipoproteins (HDL) protect the heart against ischemia/reperfusion (I/R) injury, and matrix metalloproteinase‐2 (MMP‐2) directly contributes to cardiac contractile dysfunction after I/R. To investigate the possible involvement of MMP‐2 inhibition in HDL‐mediated cardioprotection, isolated rat hearts underwent 20 min of low‐flow ischemia and 30 min of reperfusion. Plasma‐derived and synthetic HDL attenuated the I/R‐induced cardiac MMP‐2 activation and release in a dose‐dependent way. The attenuation of I/R‐induced MMP‐2 activation by HDL correlated with the reduction of post‐ischemic contractile dysfunction and cardiomyocyte necrosis. These results indicate prevention of MMP‐2 activation as a novel mechanism for HDL‐mediated cardioprotection.
Immunophilin‐ligands FK506 and CsA inhibit HIF1α expression by a VHL‐ and ubiquitin‐independent mechanism
Authors: Kong Xianguo , Lin Zhao , Caro Jaime
Published: October 2006

Hypoxia inducible factor‐1alpha (HIF1α) plays a key role in the regulation of genes controlling oxygen supply, glucose metabolism and angiogenesis. Its expression in tumors appears to confer an adaptive advantage to their hypoxic microenvironment. We have evaluated the effect of the immunophilin ligands FK506 and cyclosporin A on HIF1α levels in different tumor cell lines. Our results indicate that both drugs are potent suppressors of HIF1α expression by accelerating the proteasomal degradation of the protein. Unexpectedly, the suppressive effect of these compounds was found to be independent of the presence of von Hippel Lindau factor and the degree of hydroxylation of the HIF1α protein. Moreover, HIF1α degradation induced by these compounds did not required ubiquitination, as it was also induced in E1 ligase‐incompetent cells.
Identification of a novel, highly variable amino‐terminal amino acid sequence element in the nuclear intermediate filament protein lamin B2 from higher vertebrates
Authors: Schumacher Jens , Reichenzeller Michaela , Kempf Tore , Schnölzer Martina , Herrmann Harald
Published: October 2006

By comparing newly available cDNA sequences of the human intermediate filament protein lamin B2 with published sequences, we have identified an additional translation initiation codon 60 nucleotides upstream of the previously assumed translation start. In addition, corresponding sequences were identified in the chimpanzee, mouse, rat and bovine genes and cDNAs, respectively. Therefore, we generated antibodies against these potential 20 new amino acids of the human sequence. By immunoblot analysis and immunofluorescence microscopy we show that human lamin B2 is indeed synthesized as a longer version than previously reported, because it contains these additional 20 amino acids. Notably, the sequence homology to mouse, rat and bovine lamin B2 is significantly lower in this segment than in that between the second methionine codon and the start of the α‐helical rod indicating that the tip of the “head” is engaged in more species‐specific functions. Forced expression of the GFP‐tagged authentic “long” and the 20 amino acid shorter version of lamin B2 in human cultured SW‐13 cells demonstrated that both the longer and the shorter version are properly integrated into the nuclear lamina, although the shorter version exhibited a tendency to disturb envelope architecture at higher expression levels.
Metamorphism of Precambrian–Palaeozoic schists of the Menderes core series and contact relationships with Proterozoic orthogneisses of the western Çine Massif, Anatolide belt, western Turkey
Authors: RÉGNIER JEAN-LUC , MEZGER JOCHEN E. , PASSCHIER CEES W.
Published: October 2006

The tectonic setting of the southern Menderes Massif, part of the western Anatolide belt in western Turkey, is characterized by the exhumation of deeper crustal levels onto the upper crust during the Eocene. The lowermost tectonic units of the Menderes Massif are exposed in the Çine Massif, where Proterozoic basement orthogneisses of the Çine nappe are in tectonic contact with Palaeozoic metasedimentary rocks of the Selimiye nappe. In the southern Çine Massif, orthogneiss and metasedimentary rocks are separated by the southerly dipping Selimiye shear zone, preserving top-to-the-S shearing under greenschist facies conditions. In contrast, in the western Çine Massif, the orthogneiss is deformed and mylonitic near the contact with the metasedimentary rocks. The geometry of the mylonite zone and the observed shear directions change from north to southwest. In the north, the mylonite zone dips shallowly to the north, with top-to-the-N shear sense indicators showing northward thrusting of the orthogneiss over the metasedimentary rocks. In the southwest, the mylonite zone resembles a steep N–S striking strike-slip shear zone associated with top-to-the-SSW sense of shear. Overall, the geometry of the mylonite shear zone is consistent with northward movement of the orthogneiss relative to the metasedimentary rocks. Different shear senses are attributed to strain partitioning.

AFM diagrams and P–T pseudosections with mineral parageneses of metasedimentary rocks of the Selimiye nappe and metasedimentary enclaves within the orthogneiss of the Çine nappe indicate a single Barrovian-type metamorphism. An earlier higher pressure phase is evident from staurolite–chloritoid inclusions in garnets of the Çine nappe, suggesting a clockwise P–T path. A similar path is inferred for the Selimiye nappe. Index minerals and the sequence of mineral parageneses point to a single amphibolite facies metamorphic event affecting metasedimentary rocks of both nappes, which predates Eocene emplacement of the high pressure–low temperature Lycian and Cycladic blueschist nappes. Northward thrusting of the orthogneiss onto the metasedimentary rocks of the Selimiye nappe is coeval with amphibolite facies metamorphism. Recently postulated polymetamorphism cannot be supported by this study. Petrological data provide no evidence for burial of the lower units of the Menderes Massif to depth greater than 30 km during closure of the Neo-Tethys. A major pre-Eocene tectonic event associated with top-to-the-N thrusting and Barrovian-type metamorphism could lend support to the idea of a Neo-Tethys (sensu stricto) suture south of the Menderes Massif and below the Lycian nappes.
Does snail grazing affect growth of the old forest lichen Lobaria pulmonaria?
Authors: GAUSLAA Y. , HOLIEN H. , OHLSON M. , SOLHØY T.
Published: October 2006

Grazing marks from snails are frequently observed in populations of the old forest epiphyte Lobaria pulmonaria. However, grazing marks are more numerous in thalli from deciduous broadleaved forests than in thalli from boreal Picea abies forests, due to higher populations of lichen-feeding molluscs in deciduous stands. Here we tested for deleterious effects of snails on the lichens by transplanting 600 more or less grazed L. pulmonaria thalli from deciduous forests to snail-free P. abies forests. Subsequent measurements showed that growth rates were as high in thalli with many grazing marks as those without, suggesting that growth of mature lobes of L. pulmonaria are not inhibited by the recorded grazing pressure imposed by lichen feeding snails.
Caloplaca squamuloisidiata, a new lichen species from Portugal and Spain
Authors: van den BOOM Pieter P. G. , RICO Víctor J.
Published: October 2006

Caloplaca squamuloisidiata van den Boom & V. J. Rico is described as new to science. It is a saxicolous species, pale green to grey, with olivaceous patches, with a rimose-areolate, squamulose, lobulate and isidiate thallus, growing on inland exposed acid rock faces in the western half of the Iberian Peninsula in the Mediterranean region. Its ecology and distribution, and the lichen communities in which it was found are presented. A key to the isidiate and granular-isidiate Caloplaca species in Western Europe is also included.
Caloplaca amarkantakana, a new species in the Caloplaca sideritis group from India
Authors: JOSHI Yogesh , UPRETI Dalip K.
Published: October 2006

Caloplaca amarkantakana Y. Joshi & Upreti, a species closely related to C. pellodella and belonging to the section Sideritis, is described as new to science from India. It is characterized by a ±pruinose lobed olivaceous, grey-brown thallus having a parathecium of isodiametric cells, and by smaller ascospores and conidia.
Edward Teller Lectures—Lasers and Inertial Fusion Energy, Heinrich Hora and George H. Miley, eds.
Authors: Hoffmann Dieter H.H.
Published: October 2006

Edward Teller Lectures—Lasers and Inertial Fusion Energy, Heinrich Hora and George H. Miley, eds. Foreword by E.M. Campbell. First edition. Imperial College Press, London, 365 pp. US $63.00 ISBN: 1-86094-468-X

Since 1991, the Edward Teller Medal is awarded to individual researchers in recognition of their respective pioneering experimental or theoretical work in the field of intense laser and particle beam physics, and physics application of high power drivers, which is exactly the field that the journalLaser and Particle Beamscovers in great detail. Motivation of this research field is the investigation of properties of high energy density matter with the ultimate goal to achieve inertial fusion in the laboratory under reproducible conditions, and to develop a scientific basis for inertial fusion energy.
Stochastic heating in ultra high intensity laser-plasma interaction: Theory and PIC code simulations
Authors: PATIN D. , LEFEBVRE E. , BOURDIER A. , D'HUMIÈRES E.
Published: October 2006

In the first part, the theoretical model of the stochastic heating effect is presented briefly. Then, a numerical resolution of the Hamilton equations highlights the threshold of the stochastic effect. Finally, Particle-In-Cell (PIC) code simulations results, for experimentally relevant parameters, are presented in order to confirm the acceleration mechanism predicted by the one-particle theoretical model. This paper gives the conditions on the different experimental parameters in order to have an optimization of the stochastic heating.
Proposed scheme for compact GeV laser plasma accelerator
Authors: LIFSCHITZ A.F. , FAURE J. , GLINEC Y. , MALKA V. , MORA P.
Published: October 2006

The design of a two-stage compact GeV electron accelerator is presented. The accelerator is as follows: (1) an ultra-short electron bunch is produced in a state-of-the-art laser-plasma accelerator (injector stage), (2) it is injected into an accelerating stage consisting of a centimeter length low density plasma interacting with a petawatt laser pulse. The parameters for the injector are taken from recent experimental results showing that high quality, ultra-short, and quasi-monoenergetic electron beams are now being produced in laser-plasma accelerators. Simulations performed with WAKE show that this method can lead to the production of high quality, monoenergetic, and sub-50 fs electron bunches at the GeV energy level.
Enabling dynamic composition and coordination for autonomic Grid applications using the Rudder Agent framework
Authors: LI ZHEN , PARASHAR MANISH
Published: October 2006

This paper introduces Rudder, a peer-to-peer agent framework for supporting autonomic applications in decentralized distributed environments. The framework provides agents to discover, select, and compose elements, and defines agent interaction and negotiation protocols to enable appropriate application behaviors to be negotiated and enacted dynamically. The implementations of these protocols as well as agent coordination and negotiation activities are supported by Comet, a scalable decentralized coordination substrate. The operation and experimental evaluation of Rudder is presented.
Species diversity and resource relationships of South Georgian fungi
Authors: Smith R. I. Lewis
Published: October 2006

The occurrence and distribution of the South Georgia fungal flora, particularly Ascomycotina and Basidiomycotina, is assessed in terms of habitat and substrate preference. The 113 taxa reported comprise 37 basidiomycetes, 49 ascomycetes, six myxomycetes and at least 21 lower fungi. Peat and litter substrata associated with tall tussock grassland have a rich macro-fungal flora, and numerous species occur in bog and mire communities, some in abundance from mid to late summer. Many micro-fungi and ascomycetes colonize dying leaves and inflorescences of specific vascular plants, and a few colonize bryophytes and lichens. At least a dozen species, probably non-indigenous, are associated with rotting timber and other imported materials at former whaling stations. An intensive survey of the South Georgia mycoflora is necessary to gain better understanding of their role in decomposition and nutrient cycling processes in the principal plant communities.
Soluble carbohydrate and organic acid content of soils and associated microbiota from the Windmill Islands, Budd Coast, Antarctica
Authors: Roser David J. , Seppelt R. D. , Nordstrom O.
Published: October 2006

In the cold Antarctic environment labile organic compounds may accumulate in soil due to relatively low utilization rates by heterotrophic microorganisms. Microbial fermentation of these compounds might contribute to the development of strongly acid soils. To test this and assess concentrations, extracts of a range of soils in the Windmill Islands, Budd Coast were analysed by GLC and HPLC for the presence of low molecular weight sugars, polyols and organic acids. Concentrations of sugars and polyols up to 3300 mg g−1 were detected in cryptogam dominated soils. Some, such as trehalose, may have principally originated in the soil microflora. Soils from occupied penguin rookeries were found to possess oxalic, acetic, propionic and succinic acids at levels up to 1000 mg g−1 soil. Most other soils, however, lacked these acids at detectable levels (1–5 mg g−1 soil). No correlation was established between organic acid accumulation and soil pH although those dominated by moss and lichen had been acidified significantly when compared with barren soils. Thus while substantial pools of these readily utilized carbohydrates were probably present in cryptogam dominated soils, there was little accumulation of organic acids which could account for the acidity of mineral soils typical of the Windmill Islands.
Diet of two coastal nototheniid fish from Terra Nova Bay, Ross Sea
Authors: Vacchi M. , Mesa M. La , Castelli A.
Published: October 2006

An investigation into the feeding habits of two demersal nototheniids, Trematomus bernacchii and T. centronotus, showed that the most important prey were polychaetes, molluscs and euphausiids for T. bernacchii and polychaetes and amphipods for T. centronotus. Epifaunal (e.g. Barrukia cristata) and tube-dwelling polychaetes (Amphicteis cfr. midas and Amythas membranifera) were common in the diet of both species. Bivalvia including Adamussium colbecki were found in the diet of T. bernacchii. Epifaunal gastropods (Trochidae) were an occasional prey for T. centronotus. Amphipods (mainly Acanthonotozomatidae) and the euphausiid Euphausia frigida were the main crustacean food of T. centronotus and T. bernacchii respectively. Our data suggest a difference in the feeding behaviour of the two nototheniid species, although both appear capable of feeding on common epibenthic invertebrates.
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica
Authors: Hole M. J. , Storey B. C. , LeMasurier W. E.
Published: October 2006

Within the Jones Mountains, which form part of the Thurston Island crustal block, up to 700 m of Miocene (c. 10 Ma) pillow basalt and palagonitized volcaniclastic rocks unconformably overlie Jurassic granitic basement and Cretaceous volcanic rocks and dykes. New geochemical analyses demonstrate the alkalic nature of the basalts, which range in composition from alkali basalt to basanite. Unradiogenic Sr-isotope ratios (0.7031–0.7034), coupled with low LILE/HFSE ratios (e.g. Th/Ta c. 1.4, Rb/Nb 0.3–0.9) indicate a predominantly asthenospheric source for the basalts. The Jones Mountains basalts are geochemically similar to the alkalic basalts of Marie Byrd Land, but have consistently lower K/Ba and higher Ba/Nb ratios than Late Cenozoic alkalic basalts along the Antarctic Peninsula. These regional variations in geochemical composition apparently reflect differences in tectonic setting and are not the result of lithospheric interaction or partial melting/crystallization effects. The generation of alkalic magmas along the Antarctic Peninsula was causally related to the formation of slab windows following ridge crest-trench collision and the cessation of subduction, whereas the Jones Mountains alkalic basalts may represent the expression of the northward propagation of the head of the Marie Byrd Land plume.
Jurassic conchostracans from Carapace Nunatak, southern Victoria Land, Antarctica
Authors: Yanbin Shen
Published: October 2006

Fossiliferous horizons of the Ferrar Group at Carapace Nunatak of southern Victoria Land have yielded the richest and most diverse freshwater Jurassic biota hitherto recorded from Antarctica. Fossil conchostracans are the most important in terms of number of individuals and distributional area. Scanning electron microscopy is used to establish a new genus and species (Carapacestheria balli), and Cyzicus (Lioestheria) disgregaris Tasch is attributed to Carapacestheria disgregaris (Tasch) emend. The conchostracan fauna of the Ferrar Group, characterized by Carapacestheria, is probably of early Middle Jurassic age.
Persistent hazardous environments around stars older than the Sun
Authors: Greaves J.S.
Published: October 2006

Collisions amongst comets create belts of orbiting debris and, by using submillimetre wavelength observations, these collision zones can be imaged around nearby stars. An image of the closest Solar analogue, τ Ceti, shows that it possesses at least 20 times the content of the outer Solar System in cool debris particles. The inferred population of parent colliders is around 1 M[oplus ], also much larger than in the Sun's Kuiper Belt of comets. This system represents a different evolutionary outcome for a Sun-like star, with no Jupiter-like planet but many cometary bodies, and thus a potentially heavy and prolonged history of impacts on any inner terrestrial planets. Since τ Ceti is 10 Gyr old, life would have had to deal with massive bombardment over very long timescales. Furthermore, impactors in the 10 km-upwards class could arrive at intervals of 1 Myr or less, longer than recovery times on Earth, and so similar biology is unlikely. It is presently unknown whether nearby stars typically have comet belts similar to that of the Sun or of τ Ceti; extrapolations of existing data suggest many stars could be at least 2–5 times above the Solar debris level. Future large telescopes will be able to probe down to Solar System levels of cometary debris.
Trade rules and climate change subsidies
Authors: GREEN ANDREW
Published: October 2006

Countries can choose between a wide range of policy instruments to address climate change. While economists tend to argue for the efficiency of instruments such as environmental taxes, many countries are incorporating subsidies into their plans for limiting greenhouse gas emissions. However, these subsidies may conflict with World Trade Organization rules. This paper analyzes the potential benefits of using climate change subsidies in terms of addressing market failures as well as the risks of protectionism arising from such subsidies. It then examines World Trade Organization rules to determine whether they optimally differentiate between beneficial and harmful subsidy policies. It concludes that existing WTO rules do not provide adequate scope for legitimate subsidies and makes suggestions for reforming subsidies law.
A legal principle of special and differential treatment for WTO disputes
Authors: MITCHELL ANDREW D.
Published: October 2006

Based on the notion that the needs of developing countries are substantially different from those of developed countries, the principle of special and differential treatment (S&D) in the World Trade Organization (WTO) allows a certain degree of discrimination in favour of developing countries. This article considers the potential of this principle in resolving disputes within the WTO. S&D developed in the General Agreement on Tariffs and Trade (GATT) of 1947 and is today reflected in a series of provisions in various WTO agreements. The meaning of S&D as a broader principle could assist in interpreting such provisions. In addition, the principle of S&D could conceivably be used as part of the inherent jurisdiction of Panels and the Appellate Body in connection with procedural aspects of dispute settlement. However, the article concludes that, due to the incoherence of S&D, as well as the difficulties involved in distinguishing between developing countries and in advancing their interests as an amorphous group, S&D is presently of limited value as an independent principle in WTO dispute settlement.
Analyse von Krankenkassendaten zur Inanspruchnahme von Hilfsmitteln gegen Dekubitus
Authors: Hoffmann Falk , Scharnetzky Elke , Deitermann Bernhilde , Glaeske Gerd
Published: October 2006

Hintergrund und Fragestellung: Hilfsmittel werden zur Prävention und Behandlung von Dekubiti angewendet. Bisher liegt für Deutschland wenig systematisches Wissen über deren Inanspruchnahme vor. Patienten und Methodik: Wir führten eine Querschnittsstudie mit den Routinedaten der Gmünder ErsatzKasse (GEK) aus dem Jahr 2004 durch, um die Versorgung mit Hilfsmitteln gegen Dekubitus zu analysieren. Basierend auf den alters- und geschlechtsspezifischen Versorgungsprävalenzen für Personen mit mindestens einer Verordnung wurden Prevalence Ratios (PR) berechnet. Ergebnisse: Insgesamt erhielten 1.999 durchschnittlich 63,4 Jahre (SD: 20,7) alte Personen 2.421 Hilfsmittel gegen Dekubitus. Am häufigsten wurden Wechseldruckmatratzen (31,6%), Luftringe (13,5%) und verschieden gefüllte Sitzkissen (13,0%) abgegeben, während Weichpolstermatratzen lediglich 4,7% ausmachten. Die Versorgungsprävalenz steigt kontinuierlich mit dem Alter an, wobei sich keine geschlechtsspezifischen Unterschiede erkennen lassen. Verglichen mit den 50–59-jährigen erhalten über 90jährige Männer (PR: 43,94; 95% KI: 31,46–61,37) wie Frauen (PR: 40,61; 95% KI: 30,77–53,60) etwa 40mal häufiger Hilfsmittel gegen Dekubitus. Schlussfolgerung: Hilfsmittel gegen Dekubitus werden hauptsächlich von älteren Menschen genutzt. Die Studie gibt Hinweise darauf, dass deren Einsatz nicht immer der besten verfügbaren Evidence entspricht. Prävention und Behandlung von Dekubiti sowie die Auswahl entsprechender Hilfsmittel sollten als interdisziplinäre Aufgabe gesehen werden.
Ernährung, Probiotika, Antibiotika, antioxidative Therapie, Endoskopie bei chronischer Pankreatitis
Authors: Mössner
Published: October 2006

Die Behandlung der chronischen Pankreatitis ist stadiengerecht und beinhaltet mehrere Arme: Schmerztherapie, wenn möglich je nach Pathogenese der Schmerzen; Therapie der Komplikationen, wenn möglich interventionell endoskopisch, bei Versagen chirurgisch; Therapie der exokrinen Insuffizienz mit Pankreatin; Therapie der endokrinen Insuffizienz mit Insulin. Pseudozysten lassen sich je nach Lage transgastral, transduodenal, transpapillär, perkutan drainieren. Distale präpapilläre Pankreasgangstenosen lassen sich mittels Stents überbrücken, ebenso Gallengangsstenosen. Pankreasgangsteine, die zu einer Obstruktion führen, lassen sich mittels extrakorporal applizierter Schockwellen (ESWL) lithotripsieren und nach Papillotomie endoskopisch extrahieren. Transgastrale endoskopische Drainage von retroperitonealen Nekrosen ist noch experimentell. Prospektive Multicenter-Vergleichsstudien Operation versus interventionelle Endoskopie liegen noch nicht vor. Bei Versagen der endoskopischen Therapie oder bei Karzinomverdacht besteht die Indikation zur Operation. Eine spezifische Pankreasdiät existiert nicht. Beim schweren akuten Schub setzt sich zunehmend die enterale Ernährung via Jejunalsonde durch, obgleich überzeugende prospektive Vergleichsstudien parenterale versus enterale Ernährung noch fehlen. Auch der prophylaktische Einsatz von Antibiotika bei nekrotisierender Pankreatitis wird wieder kontrovers diskutiert. Bezüglich des Einsatzes von Probiotika zur Reduktion der Gefahr einer bakteriellen Besiedlung der Nekrosen liegen ebenfalls noch keine überzeugenden Studien vor. Die Hypothese mittels Radikalfängern wie Selen, die Schubfrequenz bei chronischer Pankreatitis zu reduzieren ist ebenfalls nicht durch Studien belegt.
Klatskin-Tumoren – Diagnostik und interventionelle Therapie
Authors: Ortner
Published: October 2006

Bei den Klatskin-Tumoren handelt es sich um maligne Tumoren des Gallenganges, die im Bereich der Hepatikusgabel und der intrahepatischen Gallengänge liegen. Das Leitsymptom der cholestatischen Ikterus, tritt erst in einem fortgeschrittenen Stadium auf. Daher kommen derzeit zur Verfügung stehende bildgebende Verfahren entweder zu spät zum Einsatz oder sind für die Frühdiagnose nicht sensitiv genug. Zur Diagnosestellung stehen Ultraschall, Magnetresonanz-Tomographie mit Cholangiopankreatikographie, Kontrastmittel-verstärkte Spiral-Computertomographie oder endoskopisch retrograde Cholangiopankreatikographie zur Verfügung. Vor Therapieentscheidung ist die Vorstellung an einem hepatobiliären Zentrum notwendig und gelegentlich braucht man zur Klärung der Resektabilität zusätzliche Methoden wie Angiographie, Positron-Emission-Tomographie, Cholangioskopie, endoskopischer oder endoluminaler Ultraschall, und schliesslich sogar eine explorative Laparoskopie. Zum Zeitpunkt der Diagnosestellung ist nur ein kleiner Prozentsatz der Patienten mit Klatskin-Tumoren kurativ operabel. Daher spielen palliative Therapien eine grosse Rolle. Die Endoprotheseneinlage ist die Methode der Wahl zur Beseitigung der Cholestase. Obwohl damit die Lebensqualität verbessert wird, ist nicht sicher, ob die Überlebenszeit damit verlängert wird. Bisherige Daten zeigen keinen sicheren Benefit durch zusätzliche Radio- und/oder Chemotherapie. Die photodynamische Therapie, eine Lichttherapie, führt, bis jetzt als einzige Zusatztherapie nicht nur zu einer Verbesserung der Cholestase und der Lebensqualität, sondern auch zu einer Verlängerung der Überlebenszeit. Daher sollte sie derzeit den Patienten angeboten werden.
Transformationale und charismatische Führung - Stand der Forschung und aktuelle Entwicklungen
Authors: Felfe Jörg
Published: October 2006

Zusammenfassung. Seit Mitte der 80er Jahre werden in der Führungsforschung verstärkt Ansätze der charismatischen bzw. transformationalen Führung diskutiert und untersucht. Nach anfänglicher Zurückhaltung ist das Konzept der transformationalen Führung auch in deutschsprachigen Ländern aufgegriffen worden und hat eine ganze Reihe weiterer Forschungsarbeiten angeregt. Dieser Übersichtsbeitrag gibt einen Überblick über den aktuellen Stand der Forschung. Berichtet werden nicht nur neue Entwicklungen im Bereich der Messung transformationaler Führung, sondern vor allem Ergebnisse, die die Bedeutung transformationaler Führung für unterschiedliche Erfolgskriterien wie Commitment, OCB und Kreativität unterstreichen. Neuere Befunde zu Mediatoren und Moderatoren helfen besser zu verstehen, wie und unter welchen Bedingungen transformationale Führung wirkt. Außerdem gibt es neue Erkenntnisse zum Einfluss der Persönlichkeit der Mitarbeiter auf den Prozess transformationaler Führung. Die Trainierbarkeit, für die es erste empirische Belege gibt, stellt eine viel versprechende Anwendungsperspektive für die Führungskräfteentwicklung dar. Nicht zuletzt werden Kontroversen und offene Fragen verdeutlicht, die von der zukünftigen Forschung aufgegriffen werden können.
Young students, satellites aid understanding of climate‐biosphere link
Authors: White Michael A. , Schwartz Mark D. , Running Steven W.
Published: October 2006

Data collected by young students from kindergarten through high school are being combined with satellite data to develop a more consistent understanding of the intimate connection between climate dynamics and the terrestrial biosphere. Comparison of the two sets of data involving the onset of budburst among trees and other vegetation has been extremely encouraging.

Surface‐atmosphere interactions involving exchanges of carbon, water, and energy are strongly affected by interannual variability in the timing and length of the vegetation growing season, and satellite remote sensing has the unique ability to consistently monitor global spatiotemporal variability in growing season dynamics. But without a clear picture of how satellite information (Figure 1) relates to ground conditions, the application of satellite growing season estimates for monitoring of climate‐vegetation interactions, calculation of energy budgets, and large‐scale ecological modeling is extremely limited.The integrated phenological analysis of field data, satellite observations, and climate advocated by Schwartz [1998], for example, has been primarily limited by the lack of geographically extensive and consistently measured phenology databases.
Galileo spacecraft returns stunning findings about Io
Authors: Showstack Randy
Published: October 2006

Since its insertion into orbit around Jupiter in December 1995, NASA's Galileo spacecraft has provided scientists with startling data about great thunderstorms on the planet, the origin of Jupiter's rings, possible oceans on the moons of Europa and Callisto, and the turbulent life of the moon Io, a fiery, colorfully scarred orb with more than 100 active volcanoes that makes it the most volcanically active body known in the Solar System.

During victory laps near the end of the workhorse's extended mission, Galileo recently risked radiation damage from the Jovian system for two dramatic swoops near Io. The spacecraft closely observed volcanic features there, many of which are named for mythological and cultural figures associated with heat, fire, thunder, and the underworld.
NOAA highlights severe weather incidents of the century
Authors: Showstack Randy
Published: October 2006

With the turning of the calendar, a number of groups have announced their man or woman of the century or even of the millennium, while others have issued top 10 lists.

In mid‐December the U.S. National Oceanic and Atmospheric Administration released its list of the top U.S. and global weather, water, and climate events of the 20th century.
The perfect haze: Scientists link 1999 U.S. pollution episode to midwest aerosol plumes and Kennedy plane crash
Authors: Showstack Randy
Published: October 2006

The crash of John F Kennedy Jrs single‐engine Piper Saratoga airplane in the waters off of Marthas Vineyard, Massachusetts, on July 16, 1999, prompted round‐the‐clock, global media coverage. Cameras panned the waters as the search began the following day, Saturday Pundits at first commented on the likelihood of survival of the late U.S. president's son, who piloted the plane, and the passengers—his wife and sister‐in‐law. Television screens displayed the projected, hour‐and‐one‐half, nighttime flight path east from New Jersey As the tragedy unfolded, coverage focused on speculation about the cause of the crash. News analysts repeatedly mentioned that haze attributed to summertime heat and high humidity levels may have sharply reduced visibility during the flight.
Former Congressional Science Fellow covers science for the British Embassy
Authors: Folger Peter
Published: October 2006

AGU's 1997–1998 Congressional Science Fellow Julie Moses works only a few miles from her previous office on Capitol Hill, but instead of helping voters from the 10th Congressional district of Ohio, she keeps alert for science and technology advancements in the United States that could help British citizens. Responding to an advertisement in the Washington Post, Moses found that her experience as a Congressional Fellow, advanced science degree, and experience as a postdoc in the U.K. constituted the right combination of skills for the job at the British Embassy.

As one of only two scientists working in the embassy, she keeps alert for ways of promoting breakthroughs by British scientists, and stays abreast of technology transfer opportunities. She also follows American public policy developments that could impact British aerospace and related technology sectors. For example, Moses notes that the congressional report issued this year on the subject of alleged transfers of sensitive missile data and technology to China, known as the Cox Report, has had ramifications for British satellite companies. Moses is also charged with making sure the embassy is prepared for any potential problems with the Y2K transition, including drafting contingency plans for employees “in case the electricity goes off.”
Report recommends spinning off the space station
Authors: Showstack Randy
Published: October 2006

United States research activities on the International Space Station (ISS) should be managed by a private organization rather than by NASA, concludes a January 11 U.S. National Research Council (NRC) report. The report, requested and funded by NASA, responds to a 1998 proposal by NASA to establish a nongovernmental organization to facilitate American ISS research.

The new organization should support the space station's research agenda—including planning and scheduling experiments, stimulating commercial research uses of the space station, and serving as an intermediary between NASA and other sources to fund commercial research, according to the report.
USGS helps forecast La Niña effect on U.S. streamflow
Authors: Showstack Randy
Published: October 2006

While many researchers and models have been probing into the impact of the current La Nina weather episode on precipitation and temperature, a new national forecast focuses specifically on this weather anomaly's effect on streamflow in the United States.

The forecast outlines probable wet and dry U.S. regions through July 2000. The information, while somewhat general and preliminary, could help some emergency managers and water use managers determine how to prepare for potential high or low stream flows—which could include floods and hydrological drought—and reservoir allocation decisions, according to report coauthor Michael Dettinger, a research hydrologist with the U.S. Geological Survey (USGS). Scientists with the Scripps Institution of Oceanography and the Western Regional Climate Center of the Desert Research Institute also contributed to the study.
New report affirms surface global warming, but falls short of reconciling temperature trends
Authors: Showstack Randy
Published: October 2006

A new report by the U.S. National Research Council (NRC) affirms that the global surface temperature on Earth has warmed during the past 20 years. The report, issued on January 13, also says the lower to mid‐troposphere has warmed less than the surface during the past two decades, and that a “substantial disparity remains” between these measurements.

“The warming trend in global‐mean surface temperature observations during the past 20 years is undoubtedly real and is substantially greater than the average rate of warming during the twentieth century;” the report, Reconciling Observations of Global Temperature Change, notes. “The disparity between surface and upper air trends in no way invalidates the conclusion that surface temperature has been rising.”
Elements of Physical Hydrology
Authors: Duffy Christopher J.
Published: October 2006

The problem with writing an introductory textbook with broad appeal in the field of hydrology is that the essential subject has been harvested by so many disciplines that a textbook written for one audience gets little traction in another. For example, engineering hydrology textbooks traditionally emphasize methods and techniques that satisfy the requirements of engineering design. With more or less emphasis, the text usually includes a survey of the mathematics, solutions, empirical prescriptions, and “tools,” while context and meaning of the equations receive a good deal less emphasis.

On the other hand, textbooks written from the perspective of environmental science provide a strong dose of concept by dealing with processes in an expository fashion. However, there is a tendency toward dialogue rather than diagnosis and the learner may not get a good sense of the analysis required for solving problems.
The Framework of Plasma Physics
Authors: Cowley Steven
Published: October 2006

There have been relatively few good textbooks on plasma physics. Most become simple reference books that might be titled, “Plasma Physics Recipes.” Despite their utility such books do not make good textbooks. For teaching, one needs a book that shows how the basic results and models are part of a coherent whole. Richard Hazeltine and Francois Waelbroeck have written such a textbook: The Framework of Plasma PhysicsAn this book, plasma physics is developed carefully and logically from basic physics principles. The book is not, however, overly formal; physical arguments are used to reduce mathematical complexity.
Canadian Environment Minister outlines transboundary issues, including air quality
Authors: Showstack Randy
Published: October 2006

In Canada, a land where hockey is king, people might call U.S. transboundary annoyances,such as air pollution, offsides.

Smog, according to Canadian Environment Minister David Anderson, recognizes no boundaries. Southern Canada imports 30%–50% of its ground‐level ozone from the United States, and air pollution causes about 1,800 deaths in Canada annually through respiratory distress and other ailments, he said.
Breathing life into the Test Ban Treaty
Authors: Showstack Randy
Published: October 2006

The Clinton Administration bombed in its attempt last year to convince the U.S. Senate to ratify the Comprehensive Nuclear Test Ban Treaty (CTBT).

Now, it appears that the Administration is ready to try again to lay the groundwork for ratification.