bluuebunny/crossref_metadata_2025 huggingface dataset:
Marine Vehicle Sensor Network Architecture and Protocol Designs for Ocean Observation
Authors: Zhang Shaowei , Yu Jiancheng , Zhang Aiqun , Yang Lei , Shu Yeqiang
Published: January 2012

The micro-scale and meso-scale ocean dynamic processes which are nonlinear and have large variability, have a significant impact on the fisheries, natural resources, and marine climatology. A rapid, refined and sophisticated observation system is therefore needed in marine scientific research. The maneuverability and controllability of mobile sensor platforms make them a preferred choice to establish ocean observing networks, compared to the static sensor observing platform. In this study, marine vehicles are utilized as the nodes of mobile sensor networks for coverage sampling of a regional ocean area and ocean feature tracking. A synoptic analysis about marine vehicle dynamic control, multi vehicles mission assignment and path planning methods, and ocean feature tracking and observing techniques is given. Combined with the observation plan in the South China Sea, we provide an overview of the mobile sensor networks established with marine vehicles, and the corresponding simulation results.
Size-dependent phase diagrams of metallic alloys: A Monte Carlo simulation study on order–disorder transitions in Pt–Rh nanoparticles
Authors: Pohl Johan , Stahl Christian , Albe Karsten
Published: January 2012

Nanoparticles of Pt–Rh were studied by means of lattice-based Monte Carlo simulations with respect to the stability of ordered D022- and 40-phases as a function of particle size and composition. By thermodynamic integration in the semi-grand canonical ensemble, phase diagrams for particles with a diameter of 7.8 nm, 4.3 nm and 3.1 nm were obtained. Size-dependent trends such as the lowering of the critical ordering temperature, the broadening of the compositional stability range of the ordered phases, and the narrowing of the two-phase regions were observed and discussed in the context of complete size-dependent nanoparticle phase diagrams. In addition, an ordered surface phase emerges at low temperatures and low platinum concentration. A decrease of platinum surface segregation with increasing global platinum concentration was observed, when a second, ordered phase is formed inside the core of the particle. The order–disorder transitions were analyzed in terms of the Warren–Cowley short-range order parameters. Concentration-averaged short-range order parameters were used to remove the surface segregation bias of the conventional short-range order parameters. Using this procedure, it was shown that the short-range order in the particles at high temperatures is bulk-like.
Partage du risque interrégional
Authors: Clévenot Mickaël , Duwicquet Vincent
Published: January 2012

Résumé Le risk-sharing doit permettre d’amortir des chocs asymétriques au sein d’une zone monétaire. Trois canaux d’ajustement peuvent jouer : les transferts publics, les crédits, et les revenus financiers entre les régions/pays. La littérature souligne la faiblesse actuelle de ce mécanisme en Europe, tandis qu’elle tend généralement à lui prêter un rôle majeur aux États-Unis. Dans ce travail, nous montrons que pour les États-Unis le canal financier est généralement surestimé. Le manque de données adéquates conduit à attribuer à tort les phénomènes induits à l’existence d’une zone monétaire optimale. Nous reproduisons les travaux au niveau européen où les données sont plus précises en montrant que l’impact du canal d’ajustement financier est réduit. Finalement, ces résultats conduisent à réévaluer le rôle du budget fédéral.
La génération internet n’est plus ce qu’elle était
Authors: Colombo Fausto , Jeanneret Yves
Published: January 2012

Résumé Si les annonces de révolutions générationnelles sont légion, elles ne dispensent pas d’examiner l’idée même de génération et le rôle des pratiques médiatiques dans la construction sociale des représentations. Après avoir montré qu’il existe des usages distincts du concept de génération, des plus déterministes aux plus constructivistes, et qu’une cohorte d’âges ne devient génération qu’au prix d’un travail interprétatif et social, l’article présente une série d’enquêtes empiriques examinant précisément les modes de construction de cette expérience. Il s’agit notamment de l’écart entre identité assignée de l’extérieur et identité éprouvée, des relations entre événement médiatique et mémoire, du processus d’apprentissage des médias et du rôle joué par les récits et énonciations dans l’invention d’une identité générationnelle.
Indépendance éditoriale et défense de la bibliodiversité en Amérique latine
Authors: Pinhas Luc
Published: January 2012

Résumé La revendication de l’indépendance éditoriale a trouvé depuis les années 1990 un terrain particulièrement favorable dans les pays d’Amérique latine où de nombreux collectifs d’éditeurs indépendants se sont formés. Le terme même de « bibliodiversité » semble d’ailleurs y avoir été initialement forgé, il y a une douzaine d’années. Cet article se donne comme premier objectif d’analyser la structuration du champ éditorial latino-américain, de manière à préciser les conditions économiques, politiques et culturelles qui sont à l’origine de ce mouvement. Il interroge ensuite la définition de l’indépendance dont se réclament les éditeurs locaux, soucieux de valoriser les particularismes culturels, et qui entendent manifester une résistance face au processus de déterritorialisation induit par les grands groupes éditoriaux transnationaux. Il présente enfin les différentes actions menées dans le dessein d’inciter les pouvoirs publics à adopter des politiques de régulation du marché du livre.
L’édition indépendante en Italie
Authors: Bechelloni Barbara
Published: January 2012

Résumé Après un bref aperçu historique sur l’évolution de l’édition de culture en Italie, qui puise ses racines dans la Rome de l’époque classique et de laquelle est née au cours des temps l’idée d’édition indépendante, l’auteur examine sur la base de plusieurs typologies d’éditeur les caractéristiques de l’édition indépendante en se référant à ses développements enregistrés dans la première décennie du xxi e  siècle. À partir d’enquêtes spécifiques sur la petite et moyenne édition, l’article fait état des chiffres du marché et de la production du livre dans ce secteur. Une étude panoramique de quelques éditeurs choisis comme exemples d’une édition indépendante qui connaît du succès vient clore cet essai.
Indépendance et édition politique en Grande-Bretagne. Le cas de quelques éditeurs « engagés »
Authors: Noël Sophie
Published: January 2012

Résumé La notion d’indépendance éditoriale revêt en Grande-Bretagne une dimension et des enjeux spécifiques du fait d’un environnement structurel (abandon du prix unique du livre, absence de subventions publiques) très différent de celui existant en France. L’exemple de maisons d’édition politiquement engagées, créées dans les années 1960 et 1970, illustre bien à quel point l’indépendance économique est sur le marché britannique un prérequis à l’indépendance dans toutes ses acceptions. Confrontées à une concurrence très vive et à des conditions commerciales difficiles, ces maisons se sont adaptées en développant des pratiques gestionnaires et marketing sophistiquées. L’absence de politique publique du livre contribue ainsi à renforcer la prégnance de la dimension commerciale du métier d’éditeur, tout en donnant à la notion d’indépendance une tonalité particulière.
Stéréotypage et artifice documentaires
Authors: Courbières Caroline
Published: January 2012

Résumé Les langages documentaires, outils professionnels de condensation de l’information, se présentent comme des systèmes de représentation des connaissances. Ils sont ici étudiés comme des discours produisant leur propre système de représentations et générant un processus de stéréotypage singulier. Ce stéréotypage, qui s’appuie sur la notion d’artifice documentaire, dépend des trois types de relations sémantiques qui fabriquent le contexte de signification des unités documentaires. Sa première étape réside dans le principe de figement documentaire selon lequel la signification d’une unité se trouve stabilisée par les relations d’équivalence qui lui octroient son statut documentaire, puis figée par les relations hiérarchiques qui l’inscrivent dans un cadre thématique identifié. Sa seconde étape relève du phénomène de fragmentation documentaire réalisé par les relations associatives qui projettent le signifié de l’unité dans un (ou plusieurs) autre(s) domaine(s) que sa classe d’inscription première.
Les figures de Bouddha comme promesses d’un « nirvâna commercial »
Authors: de Montety Caroline
Published: January 2012

Résumé Cet article interroge la façon dont une figure religieuse est mobilisée à des fins commerciales au service d’une marque. À travers l’exemple du Buddha-Bar, les enjeux, modalités et conditions de l’appro-priation de Bouddha sont analysés : comment le bouddhisme est-il mobilisé pour créer une marque et lui donner de la valeur, comment sont choisies et gérées les caractéristiques sémiotiques de l’offre, comment la circulation de la figure de Bouddha permet-elle son appropriation ? Quels rapports au sacré la consommation entretient-elle ? L’analyse et la réponse à ces différentes questions éclairent le processus à l’œuvre au Buddha-Bar de « consogénèse », processus d’appropriation et de transformation d’une forme culturelle en élément central d’une promesse commerciale.
Impact of HIV subtype on response and resistance in antiretroviral-naïve adults comparing treatment with once daily versus twice daily ritonavir boosted fosamprenavir in combination with Abacavir/Lamivudine
Authors: Ross Lisa L. , Robinson Marjorie D. , Carosi Giampiero , Lazzarin Adriano , Stellbrink Hans-Juergen , Moyle Graeme , Givens Naomi , Nichols William G.
Published: January 2012

The impact of HIV-1 subtype on resistance mutation selection and on virologic response to fosamprenavir in combination with once-daily (QD) versus twice-daily (BID) dosing of ritonavir was examined in a prospective, open label, randomized study in antiretroviral-naïve, HIV-1 infected subjects. We studied APV109141 compared QD fosamprenavir/ritonavir (1400mg/100mg) to BID fosamprenavir/ritonavir (700mg/100mg), administered in combination with a QD fixed-dose abacavir/lamivudine (600 mg/300 mg) combination tablet through 48 weeks in ART-naïve subjects. HIV genotypes were obtained from all subjects at screen. Subjects with virologic failure (VF) were also genotyped at baseline and VF. HIV subtypes observed in the ITT (n=214) population were A or AE or AG circulating recombinant forms (CRFs) 19%; B 62%; BF or BG CRFs 2%; C or CPX CRFs 7%; D 2%; F1 7%; G <1%. By TLOVR (ITT-exposed), 86/106 (81%) of subjects on QD study arm and 87/106 (82%) in the BID arm achieved plasma HIV-RNA<400 copies/mL at Week 48. Three subjects met VF criteria, 2 receiving QD fosamprenavir/ritonavir; 1 receiving BID fosamprenavir/ritonavir; (HIV subtype B, F1 A1, respectively). Baseline drug resistance was detected in 2/3 VFs: Subject 1-RT: K103K/N, T215C; major PI: V82A, L90M; and Subject 2-RT: M41L, L74V. Only virus from one subject with VF selected for any treatment-emergent mutation (Subject 1; M184V). Post-VF, Subject 3 (subtypeA1) suppressed HIV-RNA >400 copies/mL through 48 weeks. Subtype appeared to have no preferential impact on virologic response or selection for specific resistance mutations in subjects receiving fosamprenavir/ritonavir. Virologic failure rate was rare (3 subjects; each from different subtypes). At VF, virus from only one subject selected any HIV NRTI mutation (M184V); none selected major protease mutations.
Hyperbaric oxygen treatment of superficial soft tissue lesions in children with oncologic disease
Authors: Cesca Eleonora , Garetto Giacomo , Frascella Emanuela , Cesaro Simone , Dall'Igna Patrizia , Cecchetto Giovanni
Published: January 2012

This study aimed to assess the feasibility and results of hyperbaric oxygen therapy (HOT) as supportive treatment of lesions of superficial soft tissues in children with oncological diseases. This was a retrospective analysis and review of all records of children observed at the Pediatric Hematology-Oncology Department of the University of Padova and treated adjuvantly with HOT. Between 1996 and 2010, 12 patients (5 males and 7 females, median age 7 years, range 0.5-16) underwent HOT. The effectiveness of HOT varied according to the lesion treated. Ten out of 12 patients were cured. Efficacy was most questionable in 2 patients with skin graft and flaps at risk. Compliance to therapy was close to 100%. In just one case, HOT was interrupted for the appearance of local skin metastases close to the site of primary tumor. HOT showed itself to be safe and effective in most patients even those immunocompromised or critically ill.
Advanced Papillary Serous Carcinoma of the Uterine Cervix: A Case with a Remarkable Response to Paclitaxel and Carboplatin Combination Chemotherapy
Authors: Ueda Masashi , Koshiyama Masafumi , Yamaguchi Ayaka , Ukita Shingo , Ukita Masayo , Hishikawa Kenji , Kakui Kazuyo , Kim Tomoko , Shirase Tomoyuki
Published: January 2012

Papillary serous carcinoma of the uterine cervix (PSCC) is a very rare, recently described variant of cervical adenocarcinoma. This review, describes a case of stage IV PSCC whose main tumor existed in the uterine cervix and invaded one third of the inferior part of the anterior and posterior vaginal walls. Furthermore, it had metastasized from the para-aortic lymph nodes to bilateral neck lymph nodes. Immnoreactivity for CA125 was positive, whereas the staining for p53 and WT-1 were negative in both the original tumor and the metastatic lymph nodes. Six cycles of paclitaxel and carboplatin combination chemotherapy were administered and the PSCC dramatically decreased in size. The main tumor of the uterine cervix showed a complete response by magnetic resonance imaging (MRI), and on rebiopsy, more than 95% of the tumor cells in the cervix had microscopically disapperared. This is the first report of PSCC in which combination chemotherapy was used and showed a remarkable response.
Fanconi Anemia and Vaginal Squamous Cell Carcinoma
Authors: Dias Altamiro Ribeiro , de Andrade Silva Marcela Cavalcante , Carvalho Filomena Marino , de Andrade Carvalho Heloisa , Esteves Diz Maria Del Pilar , Baracat Edmund Chada , Carvalho Jesus Paula
Published: January 2012

Fanconi Anemia (FA) is an autosomal recessive disease characterized by chromosome instability, cellular hypersensitivity to DNA cross-linking agents, and increased predisposition to malignancies. We describe here a 28 year-old female with FA and vaginal squamous cell carcinoma treated by radiation therapy alone. The patient developed arm phlebitis, pulmonary fungal infection, and severe rectal bleeding, followed by hypocalcaemia, hypokalemia, vaginal bacterial and fungal infection, with subsequent leg and arm phlebitis, perineal abscess, and sepsis. The patient died 12 weeks later.
Clinical and Radiological Presentations of Pelvic Parachordoma
Authors: Huang Chun-Chao , Cheng She-Meng
Published: January 2012

Parachordoma is an extremely rare entity and there are only about 50 to 60 cases reported, in which there is only one definite pelvic parachordoma. We present a huge well-defined presacral tumor in a 48-year-old woman who has the symptoms of lower abdominal pain and difficulty in defecating. Radiological findings of the tumor on computed tomography and magnetic resonance imaging are described in detail. The reasons why we report the case are because the patient has rare clinical symptoms and because this is the second pelvic parachordoma. Then, we summarize the radiological features of parachordoma based on our study and the review of literature.
A review of operational, regional-scale, chemical weather forecasting models in Europe
Authors: Kukkonen J. , Olsson T. , Schultz D. M. , Baklanov A. , Klein T. , Miranda A. I. , Monteiro A. , Hirtl M. , Tarvainen V. , Boy M. , Peuch V.-H. , Poupkou A. , Kioutsioukis I. , Finardi S. , Sofiev M. , Sokhi R. , Lehtinen K. E. J. , Karatzas K. , San José R. , Astitha M. , Kallos G. , Schaap M. , Reimer E. , Jakobs H. , Eben K.
Published: January 2012

Abstract. Numerical models that combine weather forecasting and atmospheric chemistry are here referred to as chemical weather forecasting models. Eighteen operational chemical weather forecasting models on regional and continental scales in Europe are described and compared in this article. Topics discussed in this article include how weather forecasting and atmospheric chemistry models are integrated into chemical weather forecasting systems, how physical processes are incorporated into the models through parameterization schemes, how the model architecture affects the predicted variables, and how air chemistry and aerosol processes are formulated. In addition, we discuss sensitivity analysis and evaluation of the models, user operational requirements, such as model availability and documentation, and output availability and dissemination. In this manner, this article allows for the evaluation of the relative strengths and weaknesses of the various modelling systems and modelling approaches. Finally, this article highlights the most prominent gaps of knowledge for chemical weather forecasting models and suggests potential priorities for future research directions, for the following selected focus areas: emission inventories, the integration of numerical weather prediction and atmospheric chemical transport models, boundary conditions and nesting of models, data assimilation of the various chemical species, improved understanding and parameterization of physical processes, better evaluation of models against data and the construction of model ensembles.
Typical types and formation mechanisms of haze in an Eastern Asia megacity, Shanghai
Authors: Huang K. , Zhuang G. , Lin Y. , Fu J. S. , Wang Q. , Liu T. , Zhang R. , Jiang Y. , Deng C. , Fu Q. , Hsu N. C. , Cao B.
Published: January 2012

Abstract. An intensive aerosol and gases campaign was performed at Shanghai in the Yangtze River Delta region over Eastern China from late March to early June 2009. This study provided a complementary picture of typical haze types and the formation mechanisms in megacities over China by using a synergy of ground-based monitoring, satellite and lidar observations. During the whole study period, several extreme low visibility periods were observed with distinct characteristics, and three typical haze types were identified, i.e. secondary inorganic pollution, dust, and biomass burning. Sulfate, nitrate and ammonium accounted for a major part of PM2.5 mass during the secondary inorganic pollution, and the good correlation between SO2/NOx/CO and PM2.5 indicated that coal burning and vehicle emission were the major sources. Large-scale regions with high AOD (aerosol optical depths) and low Ångström exponent were detected by remote-sensing observation during the dust pollution episode, and this episode corresponded to coarse particles rich in mineral components such as Al and Ca contributing 76.8% to TSP. The relatively low Ca/Al ratio of 0.75 along with the air mass backward trajectory analysis suggested the dust source was from Gobi Desert. Typical tracers for biomass burning from satellite observation (column CO and HCHO) and from ground measurement (CO, particulate K+, OC, and EC) were greatly enhanced during the biomass burning pollution episode. The exclusive linear correlation between CO and PM2.5 corroborated that organic aerosol dominated aerosol chemistry during biomass burning, and the high concentration and enrichment degree of arsenic (As) could be also partly derived from biomass burning. Aerosol optical profile observed by lidar demonstrated that aerosol was mainly constrained below the boundary layer and comprised of spheric aerosol (depolarization ratio <5%) during the secondary inorganic and biomass burning episodes, while thick dust layer distributed at altitudes from near surface to 1.4 km (average depolarization ratio = 0.122 ± 0.023) with dust accounting for 44–55% of the total aerosol extinction coefficient during the dust episode. This study portrayed a good picture of the typical haze types and proposed that identification of the complicated emission sources is important for the air quality improvement in megacities in China.
Effect of primary organic sea spray emissions on cloud condensation nuclei concentrations
Authors: Westervelt D. M. , Moore R. H. , Nenes A. , Adams P. J.
Published: January 2012

Abstract. This work estimates the primary marine organic aerosol global emission source and its impact on cloud condensation nuclei (CCN) concentrations by implementing an organic sea spray source function into a series of global aerosol simulations. The source function assumes that a fraction of the sea spray emissions, depending on the local chlorophyll concentration, is organic matter in place of sea salt. Effect on CCN concentrations (at 0.2% supersaturation) is modeled using the Two-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled to the GISS II-prime general circulation model. The presence of organics affects CCN activity in competing ways: by reducing the amount of solute available in the particle and decreasing surface tension of CCN. To model surfactant effects, surface tension depression data from seawater samples taken near the Georgia coast were applied as a function of carbon concentrations. A global marine organic aerosol emission rate of 17.7 Tg C yr−1 is estimated from the simulations. Marine organics exert a localized influence on CCN(0.2%) concentrations, decreasing regional concentrations by no more than 5% and by less than 0.5% over most of the globe, assuming direct replacement of sea salt aerosol with organic aerosol. The decrease in CCN concentrations results from the fact that the decrease in particle solute concentration outweighs the organic surfactant effects. The low sensitivity of CCN(0.2%) to the marine organic emissions is likely due to the small compositional changes: the mass fraction of OA in accumulation mode aerosol increases by only ~15% in a biologically active region of the Southern Ocean. To test the sensitivity to uncertainty in the sea spray emissions process, we relax the assumption that sea spray aerosol number and mass remain fixed and instead can add to sea spray emissions rather than replace existing sea salt. In these simulations, we find that marine organic aerosol can increase CCN by up to 50% in the Southern Ocean and 3.7% globally during the austral summer. This vast difference in CCN impact highlights the need for further observational exploration of the sea spray aerosol emission process as well as evaluation and development of model parameterizations.
One decade of parallel PM10 and PM2.5 measurements in Europe: trends and variability
Authors: Barmpadimos I. , Keller J. , Oderbolz D. , Hueglin C. , Prévôt A. S. H.
Published: January 2012

Abstract. The trends and variability of PM10, PM2.5 and PMcoarse concentrations at seven urban and rural background stations in five European countries for the period between 1998 and 2010 were investigated. Collocated or nearby PM measurements and meteorological observations were used in order to construct Generalized Additive Models, which model the effect of each meteorological variable on PM concentrations. In agreement with previous findings, the most important meteorological variables affecting PM concentrations were wind speed, wind direction, boundary layer depth, precipitation, temperature and number of consecutive days with synoptic weather patterns that favor high PM concentrations. Temperature has a negative relationship to PM2.5 concentrations for low temperatures and a positive relationship for high temperatures. The stationary point of this relationship varies between 5 and 15 °C depending on the station. PMcoarse concentrations increase for increasing temperatures almost throughout the temperature range. Wind speed has a monotonic relationship to PM2.5 except for one station, which exhibits a stationary point. Considering PMcoarse, concentrations tend to increase or stabilize for large wind speeds at most stations. It was also observed that at all stations except one, higher PM2.5 concentrations occurred for east wind direction, compared to west wind direction. Meteorologically adjusted PM time series were produced by removing most of the PM variability due to meteorology. It was found that PM10 and PM2.5 concentrations decrease at most stations. The average trends of the raw and meteorologically adjusted data are −0.4 μg m−3 yr−1 for PM10 and PM2.5 size fractions. PMcoarse have much smaller trends and after averaging over all stations, no significant trend was detected at the 95% level of confidence. It is suggested that decreasing PMcoarse in addition to PM2.5 can result in a faster decrease of PM10 in the future. The trends of the 90th quantile of PM10 and PM2.5 concentrations were examined by quantile regression in order to detect long term changes in the occurrence of very large PM concentrations. The meteorologically adjusted trends of the 90th quantile were significantly larger (as an absolute value) on average over all stations (−0.6 μg m−3 yr−1).
Megacity ozone air quality under four alternative future scenarios
Authors: Butler T. M. , Stock Z. S. , Russo M. R. , Denier van der Gon H. A. C. , Lawrence M. G.
Published: January 2012

Abstract. The impact of the megacities of the world on global tropospheric ozone, and conversely, the extent to which megacities are influenced by emissios of ozone precursors from outside of the megacities is examined under the four alternative RCP (''Representative Concentration Pathway'') emissions scenarios. Despite accounting for about 6% of present-day anthropogenic emissions of ozone precursor species, the contribution of emissions from megacities to global tropospheric ozone is calculated to be 0.84%. By 2100 this contribution falls to between 0.18 and 0.62% depending on the scenario, with the lower value being for the most-polluting of the four future emissions scenarios due to stringent controls on ozone precursor emissions from highly populated areas combined with a stronger tropospheric background ozone field. The higher end of this range is from the least-polluting of the four emissions scenarios, due lower background tropospheric ozone combined with the use of a different downscaling methodology in the construction of the scenario. Although the absolute impact of megacities on global ozone is small, an important result of this study is that under all future scenarios, future air quality in megacities is expected to be less influenced by local emissions within the cities, but instead more influenced by emission sources outside of the cities. Air quality trends in the megacities of the developing world are projected to be similar to observed trends in developed world megacities over the last few decades. Assumptions made when downscaling the emissions scenarios onto the grids used in such modelling studies can have a large influence on these results. Future work should concentrate on the creation of spatially explicit scenarios of urban development for use in global chemical transport models.
The initiation of modern soft and hard Snowball Earth climates in CCSM4
Authors: Yang J. , Peltier W. R.
Published: January 2012

Abstract. Geochemical and geological evidence suggested that several global-scale glaciation events occurred during the Neoproterozoic era at 750–580 million years ago. The initiation of these glaciations is thought to have been a consequence of the combined influence of a result of low-level carbon dioxide and an approximately 6% weakening of solar luminosity. The latest version of the Community Climate System Model (CCSM4) is employed herein to explore the detailed combination of forcings required to trigger such extreme glaciation under present-day geography and topography conditions. It is found that runaway glaciation occurs in the model under the following conditions: (1) a 8–9% reduction in solar radiation with 286 ppmv CO2 or (2) a 6% reduction in solar radiation with 70–100 ppmv CO2. These thresholds are only moderately different from those found to be characteristic of the previous CCSM3 model reported recently in Yang et al. (2011a,b) for which the respective critical points corresponded to a 10–10.5% reduction in solar radiation with 286 ppmv CO2 or a 6% reduction in solar radiation with 17.5–20 ppmv CO2. The most important reason for these differences is that the sea-ice/snow albedo in CCSM4 is somewhat higher than in CCSM3. Differences in cloud radiative forcings and oceanic and atmospheric heat transports between CCSM3 and CCSM4 also influence the bifurcation points. The forcings required to trigger a "hard Snowball" Earth in either CCSM3 or CCSM4 may be not met by the conditions expected to be characteristic of the Neoproterozoic. Furthermore, there exist "soft Snowball" Earth states, in which the sea-ice coverage reaches approximately 60–65%, land masses in low latitudes are covered by perennial snow, and runaway glaciation does not develop. This is also qualitatively consistent with our previous results of the CCSM3 model. These results suggest that a "soft Snowball" solution for the Neoproterozoic is entirely plausible and may in fact be preferred.
Orientation effects of horizontal seismic components on longitudinal reinforcement in R/C frame elements
Authors: Kostinakis K. G. , Athanatopoulou A. M. , Avramidis I. E.
Published: January 2012

Abstract. The present paper investigates the influence of the orientation of recorded horizontal ground motion components on the longitudinal reinforcement of R/C frame elements within the context of linear response history analysis. For this purpose, three single-story buildings are analyzed and designed for 13 recorded bi-directional ground motions applied along the horizontal structural axes. The analysis and design is performed for several orientations of the recording angle of the horizontal seismic components. For each orientation the longitudinal reinforcement at all critical cross sections is calculated using four methods of selecting the set of internal forces needed to compute the required reinforcement. The results show that the reinforcement calculated by three of the applied methods is significantly affected by the orientation of the recording angle of ground motion, while the fourth one leads to results which are independent of the orientation of the recording angle.
Torrential floods and town and country planning in Serbia
Authors: Ristić R. , Kostadinov S. , Abolmasov B. , Dragićević S. , Trivan G. , Radić B. , Trifunović M. , Radosavljević Z.
Published: January 2012

Abstract. Torrential floods are the most frequent natural catastrophic events in Serbia, causing the loss of human lives and huge material damage, both in urban and rural areas. The analysis of the intra-annual distribution of maximal discharges aided in noticing that torrential floods have a seasonal character. The erosion and torrent control works (ETCWs) in Serbia began at the end of the 19th century. Effective protection from torrential floods encompasses biotechnical works on the slopes in the watershed and technical works on the torrent beds, within a precisely defined administrative and spatial framework in order to achieve maximal safety for people and their property. Cooperation to overcome the conflicts between the sectors of the water resources management, forestry, agriculture, energetics, environmental protection and local economic development groups is indispensable at the following levels: policy, spatial planning, practice, investments and education. The lowest and most effective level is through the Plans for Announcement of Erosive Regions (PAERs) and the Plans for Protection from Torrential Floods (PPTFs), with Hazard Zones (HZs) and Threatened Areas (TAs) mapping on the basis of the hydrologic, hydraulic and spatial analysis of the factors that are important for the formation of torrential floods. Solutions defined through PAERs and PPTFs have to be integrated into Spatial Plans at local and regional levels.
Bianchi Type—IX Barotropic Fluid Model with Time-Dependent Displacement Vector in Lyra Geometry
Authors: Bali Raj , Vadhwani Rajendra , Dhanka Jagdish Prasad
Published: January 2012

Bianchi Type IX barotropic fluid cosmological model in the frame work of Lyra geometry is investigated. To get the deterministic model of the universe, it is assumed that shear () is proportional to expansion (). This leads to , where and are metric potentials and is a constant. To get the results in terms of cosmic time , we have also considered a special case (dust filled universe) and . We find that the model starts with a big bang initially and the displacement vector () is initially large but decreases due to lapse of time. The models
and have point-type singularity at and , respectively. The physical and geometrical aspects of the models are also discussed.
Manufacturing of Silicon Carbide Knit Fabrics
Authors: Heiss Christian , Travitzky Nahum , Greil Peter
Published: January 2012

Knit fabric textile structures are processed from silicon carbide multifilament fiber rovings. The minimum bending radius of the various single silicon carbide fibers is determined from loop tension test in order to derive boundary conditions for fiber bending in the knitting process. The processing conditions for knitting are modified in order to reduce buckling and friction acting on the silicon carbide fiber rovings. Fiber knit fabrics are fabricated with a modified 2 Tempi pattern chain which leads to high flexible manufacturing. Compared to woven silicon carbide fabric structures the knitted fiber perform offers a superior flexibility, wider range of pore size and a higher degree of drapability.
In Situ Study of γ‐TiAl Lamellae Formation in Supersaturated α2‐Ti3Al Grains
Authors: Cha Limei , Schmoelzer Thomas , Zhang Zaoli , Mayer Svea , Clemens Helmut , Staron Peter , Dehm Gerhard
Published: January 2012

In situ heating transmission electron microscopy (TEM) was used to investigate the initial stage of γ‐TiAl lamellae formation in an intermetallic Ti–45Al–7.5Nb alloy (in at.%). The material was heat treated and quenched in a non‐equilibrium state to consist mainly of supersaturated, ordered α2‐Ti3Al grains. Subsequently, specimens were annealed inside a TEM up to 750 °C. The in situ TEM study revealed that ultra‐fine γ‐TiAl laths precipitate in the α2‐matrix at ≈730 °C which exhibit the classical Blackburn orientation relationship, i.e. (0001)α2//(111)γ and [$11{\bar {2}}0$]α2//<110]γ. The microstructural development observed in the in situ TEM experiment is compared to results from conventional ex situ TEM studies. In order to investigate the precipitation behavior of the γ‐phase with a complementary method, in situ high energy X‐ray diffraction experiments were performed which confirmed the finding that γ‐laths start to precipitate at ≈730 °C from the supersaturated α2‐matrix.
Gründungssanierung der Stadtkirche in Dinslaken
Authors: Müller Norbert
Published: January 2012

Die 1720 erbaute Stadtkirche in Dinslaken wurde in einem unzureichend tragfähigen, humosen Boden errichtet mit der Folge dauerhaft anhaltender Rißbildungen und Gebäudeschäden. In dem nachfolgenden Praxisbeispiel werden die Schadensursachen im Einzelnen beschrieben und die Vor‐ und Nachteile der unterschiedlichen Möglichkeiten zur Gründungssanierung gegenüber gestellt. Das bei den hier vorhandenen Rahmenbedingungen gewählte Verfahren wird abschließend vorgestellt.

Foundation renovation of the municipal church in Dinslaken

The municipal church of Dinslaken, built in 1720, has been erected on an organic soil with insufficient bearing capacity. In consequence of this, permanent crack formation and building damages occurred continously. In the following practical example the causes of damages are described in particular and advantages and disadvantages of different methods of foundation renovation are compared. Finally the method chosen in respect to the given boundary conditions will be presented.
The Influence of Terminal Push–Pull Substitution on the Electronic Structure and Optical Properties of Pentacenes
Authors: Tönshoff Christina , Bettinger Holger F.
Published: January 2012

The synthesis of 2,3‐R2‐9,10‐(OMe)2‐substituted pentacenes (R=OMe, F, Br, CN;1–4) from 2,3‐R2‐9,10‐dimethoxy‐6,13‐dihydro‐6,13‐ethanopentacene‐15,16‐diones (α‐diketone‐bridged precursors) by photochemically induced bis‐decarbonylation (Strating–Zwanenburg reaction) is described. Under matrix‐isolation conditions (solid Ar, 10 K) the S1transitions of1and2undergo hypsochromic and those of3and4bathochromic shifts compared to parent pentacene. The S1transition wavelengths correlate well with the difference of substituent parametersσp. A computational analysis of the excited states at the CAM‐B3LYP/6‐311+G** level of theory provides an assignment of the electronic transitions. Photolysis in solution at room temperature yields red [R=OMe (1)], blue [R=Br (3), F (2)], and green [R=CN (4)] pentacenes. The compounds are oxygen‐sensitive and have low solubility, but their formation can be monitored by UV/Vis and, in the case of R=CN, also by1H NMR spectroscopy. The S1transition in4does not show the typical pentacene fine structure in the electronic absorption spectrum. Photogeneration in the presence of oxygen leads to a number of photoproducts that could be identified by monitoring the reaction by1H NMR spectroscopy for R=OMe.
A Solid‐Supported Organocatalyst for Continuous‐Flow Enantioselective Aldol Reactions
Authors: Ayats Carles , Henseler Andrea H. , Pericàs Miquel A.
Published: January 2012

Asymmetric aldol reactions catalyzed by a novel polystyrene‐immobilized proline derivative occur in short reaction times with excellent diastereo‐ and enantioselectivity. The catalyst can be recovered by simple filtration and shows very high reusability. The high activity depicted by the supported catalyst and its chemical and mechanical stability have allowed its application in packed‐bed reactors for continuous flow processing. This system can produce enantio‐ and diastereomerically pure aldol adducts under continuous flow conditions with a residence time of 26 min. Furthermore, the reactor allowed processing of four different aldol products in sequence without any decrease in both catalytic activity and optical purity. The effective catalyst loading could be reduced to 1.6 % (six‐fold reduction of catalyst loading compared to the corresponding batch process).
Antisymmetry and Dynamic Antisymmetry
Authors: Barrie Michael
Published: January 2012

This paper presents an overview of the theories of Antisymmetry and Dynamic Antisymmetry. It begins with a brief history of linearization and describes the fundamental difference between parameterized word order and universal word order. It presents a technical description of Antisymmetry and Dynamic Antisymmetry followed by a less technical synopsis. It also outlines various consequences and criticisms of these two theories and describes some current research in this domain.
Molecular Weight Distribution Characteristics (of a Polymer) Derived from a Stretched‐Exponential PGSTE NMR Response Function—Simulation
Authors: Gong Xiaoliang , Hansen Eddy W. , Chen Qun
Published: January 2012

Assuming the signal response in a pulsed gradient stimulated echo (PGSTE) experiment (on a polymer) to be described by a simple stretched‐exponential function (SEF) and knowing the scaling law between diffusivity and molecular weight, the molecular weight distribution (MWD) characteristics (kurtosis, skewness, moment, and width) are derived and compared to the corresponding distribution characteristics obtained by a log‐normal function fit (to the same MWD). Also, the challenge involved in obtaining a reliable weight average molecular weight from an SEF response function is discussed.
A representation of the moment measures of the general ideal Boe gas
Authors: Nehring Benjamin , Zessin Hans
Published: January 2012

We reconsider the fundamental work of Fichtner 2 and exhibit the permanental structure of the ideal Bose gas again, using a new approach which combines a characterization of infinitely divisible random measures (due to Kerstan, Kummer and Matthes 4, 6 and Mecke 9, 10) with a decomposition of the moment measures into its factorial measures due to Krickeberg 5. To be more precise, we exhibit the moment measures of all orders of the general ideal Bose gas in terms of certain “loop” integrals. This representation can be considered as a point process analogue of the old idea of Symanzik 15 that local times and self‐crossings of the Brownian motion can be used as a tool in quantum field theory.

Behind the notion of a general ideal Bose gas there is a class of infinitely divisible point processes of all orders with a Lévy‐measure belonging to some large class of measures containing that of the classical ideal Bose gas considered by Fichtner.

It is well‐known that the calculation of moments of higher order of point processes is notoriously complicated. See for instance Krickeberg’s calculations for the Poisson or the Cox process in 5.

Relations to the work of Shirai, Takahashi 12 and Soshnikov 14 on permanental and determinantal processes are outlined.
Semi‐Synthesis and Analysis of Chemically Modified Zif268 Zinc‐Finger Domains
Authors: Fehr Friederike , Nadler André , Brodhun Florian , Feussner Ivo , Diederichsen Ulf
Published: January 2012

Total synthesis of proteins can be challenging despite assembling techniques, such as native chemical ligation (NCL) and expressed protein ligation (EPL). Especially, the combination of recombinant protein expression and chemically addressable solid‐phase peptide synthesis (SPPS) is well suited for the redesign of native protein structures. Incorporation of analytical probes and artificial amino acids into full‐length natural protein domains, such as the sequence‐specific DNA binding zinc‐finger motifs, are of interest combining selective DNA recognition and artificial function. The semi‐synthesis of the natural 90 amino acid long sequence of the zinc‐finger domain of Zif268 is described including various chemically modified constructs. Our approach offers the possibility to exchange any amino acid within the third zinc finger. The realized modifications of the natural sequence include point mutations, attachment of a fluorophore, and the exchange of amino acids at different positions in the zinc finger by artificial amino acids to create additional metal binding sites. The individual constructs were analyzed by circular dichroism (CD) spectroscopy with respect to the integrity of the zinc‐finger fold and DNA binding.
Wirkstoffe gegen Mycobacterium tuberculosis in klinischer Anwendung
Authors: Weeken Daniela , Schlitzer Martin
Published: January 2012

Viele der noch heute verwendeten Tuberkulosemittel (Tab. 1) wurden schon vor einigen Jahrzehnten in die Therapie eingeführt. Der “glückliche Zufall” hat bei der Entdeckung vieler Therapeutika eine nicht unerhebliche Rolle gespielt. Aufgrund der biochemischen Besonderheiten von M. tuberculosis weisen einige Substanzen singuläre Wirkmechanismen auf. Bei einigen neueren antimikrobiellen Substanzen ist der Anwendungsbereich erst kürzlich auf die Therapie der Tuberkulose ausgedehnt worden. Zum Teil muss sich der Stellenwert dieser Substanzen in der Behandlung der Tuberkulose noch herausstellen.
Routinemäßiges Tuberkulose‐Screening von Immigranten
Authors: Schmitz Jens
Published: January 2012

Da die Therapie der Tuberkulose langwierig und sehr teuer ist, stellt sich die Frage, ob ein routinemäßiges Screening aller Immigranten aus Hochinzidenz‐Ländern bei der ersten Einreise in Niedriginzidenz‐Länder sinnvoll und kosteneffektiv ist. Problematisch sind dabei folgende Punkte: Zum einen ist z.B. die Anzahl falsch‐negativer Testergebnisse relativ hoch, zum anderen werden z.B. illegale Einwanderer, Gastarbeiter und Austauschstudenten nicht erfasst. Es ist sicherlich besser, einen globalen Ansatz zu verfolgen und die Ausbreitung der Tuberkulose in Hochinzidenz‐Ländern durch z.B. Verbesserung der Lebensbedingungen, des Gesundheitssystems und Überwachung der Therapie zur Sicherung der Compliance zu verhindern. Im Falle einer diagnostizierten Tuberkulose ist es außerdem zwingend notwendig, Kontaktpersonen ausfindig zu machen, diese zu testen und ggf. erfolgreich zu therapieren.
Experimentelle Impfung gegen Tuberkulose
Authors: Winckler Thomas
Published: January 2012

Eine aktuelle Studie zeigt einen neuen Weg zur Entwicklung von Impfstoffen gegen Tuberkulose auf, der möglichweise in Zukunft den umstrittenen BCG‐Impfstoff ersetzen kann.
Gekoppelte Uhren, Geistertöne und Gedankenblitze
Authors: Euler Manfred
Published: January 2012

Uhren bringen sich selbsttätig in Gleichgang, verstimmte Orgelpfeifen ertönen spontan unisono. Die wie Zaubertricks anmutenden Experimente geben Einblicke in die Bedeutung dynamischer Kopplungs‐ und Bindungsprozesse. Entscheidend ist dabei das Zusammenspiel zwischen linearen und nichtlinearen Effekten. Das geschieht auch in unserer Wahrnehmung: Doppelpfeifen erzeugen Geistertöne, die erst in unserem Gehör entstehen. Unsere Hirnströme zeigen ebenfalls auffällige Oszillationen synchronisiert feuernder Nervenzellen, wenn wir zum Beispiel Gesichter betrachten. Offenbar spielen universelle Synchronisationsprozesse auch in der Konstruktion unserer inneren Wirklichkeit eine wichtige Rolle.
Ein Bierbrauer blickt in die Sonne
Authors: Loos Andreas
Published: January 2012

In einem kleinen Örtchen im Südwesten Englands kauft Mitte des vorletzten Jahrhunderts ein junger Mann ein Stück Sumpfwiese und lässt darauf eine Sternwarte nebst Wohnhaus errichten. Mit seinen Bogenfenstern und dem spitzen Giebel erinnert das Gebäude entfernt an das Trinity College, wo er studiert hat. Seine bedeutendste Entdeckung macht der Gesuchte jedoch nicht bei Beobachtungen des nächtlichen Sternenhimmels, sondern der Sonne.
Thüringer Klöße – wasserbindende Saucenauftunkwunder
Authors: Vilgis Thomas
Published: January 2012

Was wäre ein Festtagsbraten in Thüringen ohne die berühmten Thüringer Klöße? Unvorstellbar. Diese schmackhaften Kugeln strotzen vor Geschmack und bestechen durch ihre besonders geschätzte Fähigkeit, Saucen aufzusaugen. Dies liegt an der traditionellen Zubereitungstechnik, die – unbewusst – zum Großteil auf den physikalischen Eigenschaften des Amylopektins, den hochgradig verzweigten Stärkemolekülen der Kartoffeln, beruht.
Gitter aus magnetischen Wirbeln
Authors: Heinze Stefan , von Bergmann Kirsten , Bihlmayer Gustav
Published: January 2012

Ein zentrales Problem der voranschreitenden Miniaturisierung magnetischer Datenspeicher ist die Stabilität der Magnetisierung von Nanostrukturen. Magnetische Skyrmionen – wirbelförmige Spinstrukturen von außergewöhnlicher Stabilität – bieten aufgrund ihres topologischen Schutzes eine ungewöhnliche Perspektive. Nun hat unsere Kollaboration aus Hamburg, Jülich und Kiel erstmals ein regelmäßiges Gitter aus magnetischen Skyrmionen auf einer Oberfläche gefunden. Quantenmechanische Rechnungen konnten klären, warum die Natur diese magnetischen Wirbel ausbildet.
Einzelne Elektronen surfen auf einer Schallwelle
Authors: Bäuerle Christopher , Meunier Tristan , Wieck Andreas Dirk , Tarucha Seigo
Published: January 2012

Schaltkreise, die mit einzelnen Elektronen arbeiten, können die Leistungsfähigkeit von Computern enorm steigern. Sie benötigen aber einen Mechanismus, um einzelne Elektronen zu befördern. Zwischen Quantenpunkten ist dies nur möglich, wenn diese sehr eng beieinander liegen. Am Institut‐Néel CNRS Grenoble ist es unserer Forschergruppe zusammen mit Kollegen aus Tokio und Bochum gelungen, einzelne Elektronen mit einer Schallwelle zwischen zwei benachbarten Quantenpunkten zu befördern. Dies bedeutet einen großen Schritt in Richtung Quanten‐Informationstechnologie mit einzelnen Elektronen.
Getunkt und nicht gebröselt
Authors: Schlichting H. Joachim
Published: January 2012

Nicht nur in der Weihnachtszeit muss man sich genau überlegen, ob man Kekse trocken und bröselig zu sich nimmt oder ob man ihnen durch Eintunken in ein heißes Getränk eine mundgerechtere Konsistenz verleiht. Warum manche Menschen aufgeweichte Kekse mögen, muss hier unbeantwortet bleiben. Uns interessiert lediglich die Frage, warum ein harter Keks seine Konsistenz in einer Flüssigkeit so drastisch verändert.