bluuebunny/crossref_metadata_2025_split huggingface dataset:
Licht im Rückwärtsgang
Authors: Dolling Gunnar , Linden Stefan , Wegener Martin 
Published: June 2006

AbstractMetamaterialien können qualitativ neuartige optische Eigenschaften besitzen, zum Beispiel eine negative optische Brechzahl. Die resultierende negative Phasengeschwindigkeit des Lichts ist sicher gewöhnungsbedürftig. Kürzlich konnte dieses Phänomen aber ein internationales Team mit Wissenschaftlern aus Karlsruhe und Heraklion direkt nachweisen.
Auf dem Weg zum International Linear Collider
Authors: Elsen Eckhard 
Published: June 2006

AbstractFührende Beschleuniger‐ und Teilchenphysiker in Amerika, Asien und Europa arbeiten gemeinsam an der Planung des International Linear Collider (ILC). In dieser etwa 30 Kilometer langen Maschine werden Elektronen und Positronen beschleunigt und mit bisher unerreicht hohen Energien aufeinander prallen. Die Wissenschaftler erwarten davon Einblicke in die Welt jenseits des Standardmodells.
Visualisierung mit der Schlierenmethode
Authors: Heering Peter 
Published: June 2006

AbstractDer Name des österreichischen Forschers Ernst Mach ist heute noch mit der Schallgeschwindigkeit verbunden. Diese Auszeichnung resultiert aus Machs Untersuchungen, wie sich Projektile mit Überschallgeschwindigkeit durch die Luft bewegen. Gerade in jüngster Zeit hat die Anwendung derartiger Methoden durch technische Modifikationen wieder einen Aufschwung erfahren.
Phæno Wolfsburg – die Welt entdecken
Authors: Rösner Peter 
Published: June 2006

AbstractIn Deutschlands jüngstem Science Center, dem phæno in Wolfsburg, öffnet sich die faszinierende und spannende Welt von Naturwissenschaft und Technik. Die Besonderheit und Schönheit verblüffender, grundlegender und auch rätselhafter naturwissenschaftlicher Phänomene am eigenen Leib zu erleben, dies ist das Thema von phæno.
Pervaporation properties of crosslinked poly(dimethylsiloxane) membranes for the removal of hydrocarbons from water
Authors: Ohshima Tadahiro , Kogami Yoshihisa , Minakuchi Masashi , Miyata Takashi , Uragami Tadashi 
Published: June 2006

AbstractThe pervaporation (PV) performance of crosslinked poly(dimethylsiloxane) dimethylmethacrylate (PDMSDMMA) membranes for an aqueous solution of various hydrocarbons was studied using sorption–diffusion theory. Three chlorinated hydrocarbons (chloroform, trichloroethylene, and tetrachloromethane) and three aromatic hydrocarbons (benzene, chlorobenzene, and toluene) were used as the permeants. When aqueous solutions of 0.05 wt % hydrocarbon were permeated through the crosslinked PDMSDMMA membranes, they showed high hydrocarbon/water selectivity and permeability during PV. The hydrocarbon/water selectivity of the crosslinked PDMSDMMA membranes was significantly dependent upon the permeants; in particular, chloroform removed the hydrocarbons most efficiently in this study. The results of the temperature dependence of the PV performance and hydrocarbon absorption into the membrane revealed that the difference in hydrocarbon/water selectivity for various aqueous solutions of hydrocarbons during PV depended significantly on the molar volume and diameter of the hydrocarbons. The permeation and removal mechanism of hydrocarbons from water through crosslinked PDMSDMMA membranes can be explained by a qualitative model based on the diffusion jump model. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2079–2090, 2006
Microstructure and protonic conductivity of H3PO4‐doped polyethylenimine–siloxane chemically covalently organic–inorganic hybrids
Authors: Liang Wuu‐Jyh , Hsieh Shang‐Ju , Hsu Chang‐Yu , Chen Wei‐Fu , Kuo Ping‐Lin 
Published: June 2006

AbstractThe chemically covalent polyethylenimine–siloxane hybrids doped with various amounts of ortho‐phosphoric acid (H3PO4) were prepared and characterized by FTIR, DSC, TGA, and solid‐state NMR spectra. The protonic conduction behavior of these materials was also investigated by means of impedance measurements. These observations indicate that the hydrogen bonding and protonic interactions exist between the dopant H3PO4 and the hybrid host, resulting in an increase in T
g of polyethylenimine segments. These hybrids are thermally stable up to 200 °C from TGA analysis. Conductivity studies show an Arrhenius behavior characteristic and the Grotthus‐like proton conduction, and a high conductivity of 10−2–10−3 S cm−1 at 110 °C in dry atmosphere for the hybrid membrane with H3PO4/EI of 0.5. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2135–2144, 2006
Statistical potential‐based amino acid similarity matrices for aligning distantly related protein sequences
Authors: Tan Yen Hock , Huang He , Kihara Daisuke 
Published: June 2006

AbstractAligning distantly related protein sequences is a long‐standing problem in bioinformatics, and a key for successful protein structure prediction. Its importance is increasing recently in the context of structural genomics projects because more and more experimentally solved structures are available as templates for protein structure modeling. Toward this end, recent structure prediction methods employ profile–profile alignments, and various ways of aligning two profiles have been developed. More fundamentally, a better amino acid similarity matrix can improve a profile itself; thereby resulting in more accurate profile–profile alignments. Here we have developed novel amino acid similarity matrices from knowledge‐based amino acid contact potentials. Contact potentials are used because the contact propensity to the other amino acids would be one of the most conserved features of each position of a protein structure. The derived amino acid similarity matrices are tested on benchmark alignments at three different levels, namely, the family, the superfamily, and the fold level. Compared to BLOSUM45 and the other existing matrices, the contact potential‐based matrices perform comparably in the family level alignments, but clearly outperform in the fold level alignments. The contact potential‐based matrices perform even better when suboptimal alignments are considered. Comparing the matrices themselves with each other revealed that the contact potential‐based matrices are very different from BLOSUM45 and the other matrices, indicating that they are located in a different basin in the amino acid similarity matrix space. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Structural characterization of the Acetobacter xylinum endo‐β‐1,4‐glucanase CMCax required for cellulose biosynthesis
Authors: Yasutake Yoshiaki , Kawano Shin , Tajima Kenji , Yao Min , Satoh Yasuharu , Munekata Masanobu , Tanaka Isao 
Published: June 2006

AbstractPrevious studies have demonstrated that endoglucanase is required for cellulose biosynthesis both in bacteria and plants. However, it has yet to be elucidated how the endoglucanases function in the mechanism of cellulose biosynthesis. Here we describe the crystal structure of the cellulose biosynthesis‐related endo‐β‐1,47‐glucanase (CMCax; EC 3.2.1.4) from the cellulose‐producing Gramnegative bacterium, Acetobacter xylinum (= Gluconacetobacter xylinus), determined at 1.65‐Å resolution. CMCax falls into the glycoside hydrolase family 8 (GH‐8), and the structure showed that the overall fold of the CMCax is similar to those of other glycoside hydrolases belonging to GH‐8. Structure comparison with Clostridium thermocellum CelA, the best characterized GH‐8 endoglucanase, revealed that sugar recognition subsite +3 is completely missing in CMCax. The absence of the subsite +3 leads to significant broadness of the cleft at the cellooligosaccharide reducing‐end side. CMCax is known to be a secreted enzyme and is present in the culture medium. However, electron microscopic analysis using immunostaining clearly demonstrated that a portion of CMCax is localized to the cell surface, suggesting a link with other known membrane‐anchored endoglucanases that are required for cellulose biosynthesis. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Inference methods for saturated models in longitudinal clinical trials with incomplete binary data
Authors: Song James X. 
Published: June 2006

AbstractIn the longitudinal studies with binary response, it is often of interest to estimate the percentage of positive responses at each time point and the percentage of having at least one positive response by each time point. When missing data exist, the conventional method based on observed percentages could result in erroneous estimates. This study demonstrates two methods of using expectation‐maximization (EM) and data augmentation (DA) algorithms in the estimation of the marginal and cumulative probabilities for incomplete longitudinal binary response data. Both methods provide unbiased estimates when the missingness mechanism is missing at random (MAR) assumption. Sensitivity analyses have been performed for cases when the MAR assumption is in question. Copyright © 2006 John Wiley & Sons, Ltd.
GSA algorithm applied to electronic structure II: UHF‐GSA method
Authors: Dias De Andrade Micael , Nascimento Marco , Mundim Kleber , Malbouisson Luiz 
Published: June 2006

AbstractIn this paper we propose a stochastic algorithm to investigate the real unrestricted Hartree–Fock problem. The approach is based on a global optimization method, the Generalized Simulated Annealing. The main characteristic of this method is that it enables the mapping of the electronic hyper‐surface in such a way as to guarantee that the absolute minimum of the functional in focus will be achieved. We tested this methodology by determining the Hartree–Fock ground‐state of the H2, LiH, BH, CH+, OH−, FH, CO, N2, BeH2, H2O, NH3, HCHO, CH4, CH, NH, CH2, NH2, OH and O2 molecules using minimal, double‐zeta, triple‐zeta and with polarization basis sets. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
X‐ray Structural Characterization of Diethyl Ether Solvated Lithium Iodide Derived from a Metathesis Reaction
Authors: Brym Markus , Jones Cameron , Junk Peter C. , Kloth Marc 
Published: June 2006

Abstract[LiI(Et2O)]4 was isolated from the reaction mixture following the reaction of [Li(FIso)(Et2O)n] (HFIso = N,N′‐di(2,6‐diisopropylphenyl)formamidine) with GaI. [LiI(Et2O)]4 was characterized by X‐ray crystallography and was shown to be a centrosymmetric tetranuclear species with a pseudo‐cubane core, and isostructural to its chloride and bromide counterparts.
Ag2Te2O7, ein neues Silbertellurat mit Weberit‐Struktur
Authors: Klein Wilhelm , Curda Jan , Peters Eva‐Maria , Jansen Martin 
Published: June 2006

AbstractAg2Te2O7, a Novel Silver Tellurate of Weberite Structure TypeAg2Te2O7 has been synthesized by solid state reaction of Ag2O and TeO2 under elevated oxygen pressure. The compound is diamagnetic and insulating, and decomposes at 560 °C in an Ar atmosphere into oxygen, Ag2TeO3 and TeO2. Ag2Te2O7 crystallizes orthorhombic in space group Imma with a = 7.266(2), b = 10.1430(9), c = 7.6021(17) Å, V = 560.3(2) Å3, Z = 4, 410 independent reflections, R1 = 4.65 %, wR2 = 11.13 %. The crystal structure consists of a three‐dimensional framework of TeO6 octahedra which are linked by common vertices. Voids of the framework accommodate silver atoms which are coordinated by eight oxygen atoms. The structure derives from that one of naturally occurring Weberite, Na2MgAlF7. The relationship to the pyrochlore structure type is discussed.
New Saccharinato/Ammonia Complexes of Nickel(II) and Zinc(II). A Structural and Spectroscopic Study
Authors: Williams Patricia A. M. , Ferrer Evelina G. , Baeza Natalia , Piro Oscar E. , Baran Enrique J. 
Published: June 2006

AbstractPart of the unit cell parameters reported in Table 1 for [Zn(sac)2(NH3)2] are incorrect. The correct values are as follows:a/Å : 7.004(1); b/Å : 11.639(2); c/Å : 12.571(2) and the unit cell volume/Å3 : 917.1(3)
Coming Out, Visibility, and Creating Change: Empowering Lesbian, Gay, and Bisexual People in a Rural University Community
Authors: D'Augelli Anthony R. 
Published: June 2006

AbstractPersonal and professional challenges faced in encouraging the development of a gay community in a rural university setting are described. Community psychologists who are lesbian, gay, or bisexual (LGB) must assess their willingness to be open and the roles they can play in developing helping resources. These issues concern how to encourage the empowerment of others while maintaining a collaborative role in a situation of major personal investment. Two specific challenges–developing informal helping resources for local LGB people and fostering institutional and policy changes to make the university a safer place for LGB faculty, staff, and students–are described. Community psychologists must consider personal risk when they become involved in empowerment efforts with this population.
America, China & the Scramble for Africa's Oil
Authors: Klare Michael , Volman Daniel 
Published: June 2006

After decades of Cold War, when Africa was simply viewed as a convenient pawn on the global chessboard, and a further decade of benign neglect in the 1990s, the African continent has now become a vital arena of strategic and geopolitical competition for not only the United States, but also for China, India, and other new emerging powers. The main reason for this is quite simple: Africa is the final frontier as far as the world's supplies of energy are concerned with global competition for both oil and natural gas (particularly the latter) becoming just as intense – if not even more so – than the former.
The factors behind the growing attention to African energy supplies are well known; so we will only summarise them here.1 World oil production is only just meeting world demand and old fields are being drained faster than new production can be brought on line. Supplies will be tight for the foreseeable future, so any new source of supply is significant. Most importers are also trying to reduce their dependence on Middle Eastern oil. In the next 10-15 years, most of the new oil entering the world market is going to be coming from African fields because it is only in Africa – and to a lesser extent in the volatile Central Asia region – that substantial new fields have been found and brought into production.
Identifying systems' new initial conditions as influence points for the future
Authors: Aaltonen Mika , Irene Sanders T. 
Published: June 2006

PurposeThe purpose of this research paper is to review and contrast traditional foresight methods through the lens of one of the key insights about complex adaptive systems – namely, a system's sensitive dependence on initial conditions.Design/methodology/approachForesight methods have often been criticized about their linear way of looking at the future. Insights from complex adaptive systems research, however, provide a new theory‐driven approach for developing real foresight methods as opposed to traditional forecasting methods based primarily on linear extrapolation. This serves as a starting point for the re‐analysis and re‐classification of the foresight methods, presented profoundly in the American Council for the United Nation's University Millennium Project's Futures Research Methodology – V2.0.FindingsThe findings of the analysis show which foresight methods actually present the future as a continuation of the present, and which instead are able to identify a system's new and emerging initial conditions; and what kind of possible understanding of the system the methods offer to the user.Research limitations/implicationsThis research paper provides a new perspective to reopen the discussion about the necessary qualities of foresight methods. This paper argues that instead of trying to forecast the future the foresight methods should help us to see and influence the future as it is emerging.Practical implicationsDiscussion and guidelines for methodological work and an introduction of complex systems concept‐tools map, a new set of methods and the way how it could be used together with Futures Research Methodology – V2.0 represent vast implications for organizations' foresight practices.Originality/valueThe origins of novelty are two: the complex adaptive systems perspective to discuss foresight methods, and the presentation of the new set of methods to support and complement Futures Research Methodology – V2.0.
Constructing and using scenarios to forecast demand for future mobile communications services
Authors: Forge Simon , Blackman Colin , Bohlin Erik 
Published: June 2006

PurposeAims to present a pragmatic method for long‐term forecasting and to illustrate its usage with the results of a recent case study to forecast future demand for mobile communications services.Design/methodology/approachA scenario construction methodology is explained in detail. The case material presented here is drawn from a forecasting exercise for the European Commission between September 2004 and April 2005 examining potential demand for mobile communications services up to 2020.FindingsThe formalized method and a synopsis of the actual scenarios generated in the case study are given here in outline. The paper also indicates how needs analysis was used in conjunction with the scenarios to generate a list of potential services and their use, which formed the basis of detailed traffic estimates. Certain aspects of the method and its results have been incorporated by the ITU working committees into their detailed preparations for the World Radiocommunication Conference's negotiations in 2007.Research limitations/implicationsThis paper can only give a brief description of the scenarios and provides only limited detail on how the scenarios were subsequently used to generate forecasts of demand for mobile communication services.Originality/valueThe paper demonstrates a socio‐economic forecasting method based on scenarios and their use in forecasting demand within the telecommunications sector.
Lipopolysaccharide exposure makes allergic airway inflammation and hyper‐responsiveness less responsive to dexamethasone and inhibition of iNOS
Authors: Komlósi Z. I. , Pozsonyi É. , Tábi T. , Szökő É. , Nagy A. , Bartos B. , Kozma G. T. , Tamási L. , Orosz M. , Magyar P. , Losonczy G. 
Published: June 2006

SummaryAllergic airway disease can be refractory to anti‐inflammatory treatment, whose cause is unclarified. Therefore, in the present experiment, we have tested the hypothesis that co‐exposure to lipopolysacharide (Lps) and allergen results in glucocorticoid‐resistant eosinophil airway inflammation and hyper‐responsiveness (AHR). Ovalbumin (Ova)‐sensitized BALB/c mice were primed with 10 μg intranasal Lps 24 h before the start of Ova challenges (20 min on 3 consecutive days). Dexamethasone (5 mg/kg/day) was given on the last 2 days of Ova challenges. AHR, cellular build‐up, cytokine and nitrite concentrations of bronchoalveolar lavage fluid (BALF) and lung histology were examined. To assess the role of iNOS‐derived NO in airway responsiveness, mice were treated with a selective inhibitor of this enzyme (1400W) 2 h before AHR measurements. More severe eosinophil inflammation and higher nitrite formation were found in Lps‐primed than in non‐primed allergized mice. After Lps priming, AHR and concentrations of T‐helper type 2 cytokines in BALF were decreased, but still remained significantly higher than in controls. Eosinophil inflammation was partially, while nitrite production and AHR were observed to be largely dexamethasone resistant in Lps‐primed allergized animals. 1400W effectively and rapidly diminished the AHR in Ova‐sensitized and challenged mice, but failed to affect it after Lps priming plus allergization. In conclusion, Lps inhalation may exaggerate eosinophil inflammation and reduce responsiveness to anti‐inflammatory treatment in allergic airway disease.
Exploiting the potential of routine data to better understand the disease burden posed by allergic disorders
Authors: Anandan C. , Simpson C. R. , Fischbacher C. , Sheikh A. 
Published: June 2006

SUMMARYThe Department of Health and Scottish Executive are currently undertaking independent reviews of allergy services in England (and Wales) and Scotland. Each review will assess the disease burden posed by allergic problems, involving secondary analyses of routine National Health Service (NHS) datasets. Major suggestions for re‐structuring and/or re‐focusing the NHS efforts to better deal with allergic disease are anticipated. The UK has some of the best datasets of routine health data in the world, but despite their strengths, they have important limitations. These include gaps in data collection, particularly in relation to monitoring of Accident & Emergency and out‐patient consultations, and in‐patient prescribing, thereby resulting in considerable under‐estimates of hospital workload. The current gaps in service monitoring are likely to under‐estimate the burden and workload associated with allergic problems, particularly in secondary care. One major limitation of existing data sources is the general inability to link individual patient level data between different datasets. By unlocking this potential there are very considerable potential gains to be made. Data linkage techniques currently being developed in the UK offer exciting new possibilities of looking across the primary‐, secondary‐ and tertiary‐care interfaces and also assessing short‐and long‐term social and educational outcomes in relation to allergic disorders. The current reviews of allergy services being undertaken need to be cognisant of these inherent limitations of existing data sources and would do well to recommend strategic initiatives that could enhance the availability, accessibility and quality of these datasets. Ideally, this should include investment in central data repositories staffed by teams with the necessary technical and statistical expertise, which would also take responsibility for progressing data linkage capabilities.
Follistatin is a candidate endogenous negative regulator of activin A in experimental allergic asthma
Authors: Hardy C. L. , O'Connor A. E. , Yao J. , Sebire K. , De Kretser D. M. , Rolland J. M. , Anderson G. P. , Phillips D. J. , O'Hehir R. E. 
Published: June 2006

SummaryBackground
Activin A is a member of the transforming growth factor‐β superfamily which is directly implicated in airway structural change and inflammation in asthma. In vitro, the biological effects of activin A are neutralized by the soluble binding protein follistatin.Objective
To determine the potential of endogenous follistatin to suppress activin A in vivo by analysing their relative tissue and kinetic compartmentalization during the effector phase of subchronic Th2‐driven mucosal inflammation in a murine model of allergic asthma.Methods
Eosinophilic mucosal inflammation was elicited by triggering Th2 recall responses by antigen challenge in ovalbumin‐sensitized BALB/c mice. The kinetics and distribution of activin A and follistatin protein were assessed in lung tissue and bronchoalveolar lavage fluid and measured in relation to airway eosinophilia, goblet cell metaplasia and Th2 cytokine production in mediastinal lymph nodes.Results
Follistatin was released concurrently with activin A suggesting it acts as an endogenous regulator: peak BAL concentrations coincided with maximal airway eosinophilia, and frequency of IL‐4, IL‐5 and IL‐13 producing cells in mediastinal lymph nodes but induction lagged behind the onset of inflammation. Follistatin and activin A immunoreactivity were lost in airway epithelial cells in parallel with goblet cell metaplasia. Exogenous follistatin inhibited the allergen‐specific Th2 immune response in mediastinal lymph nodes and mucus production in the lung.Conclusion
Follistatin is preformed in the normal lung and released in concert with activin A suggesting it serves as an endogenous regulator. Disturbance of the fine balance between activin A and its endogenous inhibitor follistatin may be a determinant of the severity of allergic inflammation or tissue phenotypic shift in asthma.