bluuebunny/crossref_metadata_2025 huggingface dataset:
Ground instability in the old town of Agrigento (Italy) depicted by on-site investigations and Persistent Scatterers data
Authors: Cigna F. , Del Ventisette C. , Gigli G. , Menna F. , Agili F. , Liguori V. , Casagli N.
Published: December 2012

Abstract. We combine on-site investigations with the interpretation of satellite Persistent Scatterers (PS) to analyse ground instability in the historic town of Agrigento, Italy. Geological and geomorphologic surveys, together with geostructural and kinematic analyses, depict the deformational patterns of the northwestern sector of the town, previously documented by extensive literature available for the neighbouring Valley of the Temples. The geological and geomorphologic maps are reconstructed by combining bibliographic studies, field surveys and aerial stereo-interpretation. ERS-1/2 PS data reveal deformation velocities up to 18–20 mm yr−1 in 1992–2000 over the Addolorata landslide, and a sudden motion of 1.6 cm over the Bishop's Seminary in 1999. RADARSAT-1 PS data highlight velocities of 3.0 mm yr−1 for St. Gerlando's Cathedral and reveals worsening of its structural instability since 2006. Ground instability of the town is controlled by low quality and high fracturing of the Agrigento formation rock masses, and the remarkable contrast between different mechanical behaviours of its calcarenite (brittle), silt and clay (plastic) facies. Slow landslides and widespread erosion are also recognised in the clays of the underlying Monte Narbone formation. Coexistence of these factors induces progressive retrogression of the edge of the Girgenti hill and damages the overlying historic buildings, whose stability and safe accessibility are nowadays almost compromised.
Diversity of Pathogenic Candida Species Colonizing Women with and without Candida Vaginitis in Dar es Salaam Region, Tanzania
Authors: Namkinga Lucy Andrew
Published: December 2012

The aim of this study was to establish phenotypic and genetic diversities of Candida species isolated from women with recurrent Candida vaginitis. A total of 3000 samples were cultured from 3000 women with and without complaints of vaginal discharges and pruritis vulvae. Growth characteristics on Sabouraud’s dextrose agar and on conidia enhancing media (Corn meal agar) resulted in isolation of 5440 distinct colonies of Candida species. They were then analyzed by germ tube test to separate C. albicans from non-albicans Candida species. For confirmation, 300 doubtful isolates were then tested on API 20C AUX and by polymerase chain reaction.The results showed Candida albicans species to be dominant 3661 (67.29%) while non-albicans Candida species presented only 1779 (32.71%) which included C. glabrata 435(8.0%), C. tropicalis 762(14.0%), C. krusei 163(3.0%), C. famata 109(2.0%), C. parapsilosis 131(2.41%), C. guilliermondii and C. lusitaniae each 27(0.5%) respectively, C. incospicua 13 (0.24%), C. norvegensis 82(1.5%), C. colliculosa 16 (0.3%) and C. magnoliae 15 (0.27%). On genotypic diversity, the principle coordinate analysis of the PCR results for the genetic relatedness and genetic distances revealed the distribution of 200 isolates tested as: C. albicans 90(36%), C. glabrata 40(20%),  C. krusei 20 (10%),  C. tropicalis 20 (10%),  C. famata 10(5%),  C. parapsilosis 5(2.5%), C. norvegensis 6(3%), C. lusitaniae 4(2%), and C. guilliermondii 5(2.5%).  From this study it shows that a combination of biochemical methods and PCR technology may identify most of the isolates, including the germ tube negative isolates. Both symptomatic and asymptomatic women possessed similar species and genotypic diversities. However, in symptomatic women, a single host can be colonized with multiple species or multiple genotypes of the same species.  In order to establish if the same species behave differently in symptomatic and asymptomatic individuals, this study recommend further investigation on virulent factors.
Frequency Dependent Model of Leakage Inductance for Magnetic Components
Authors: Wilson P. R. , Wilcock R.
Published: December 2012

Theoretical methods for the calculation of winding losses with respect to frequency have been well documented, but the variation in leakage inductance of magnetic components due to frequency has been less well addressed. In this paper Dowell’s well-known theoretical approach is tested using measurements and finite element analyses. The results presented show deficiencies in the accuracy of models generated using Dowell’s approach and highlight the trade-offs between model complexity, simulation time and accuracy when the finite element analysis method is applied. An alternative behavioral model is presented which models the frequency variation in leakage inductance accurately, is easy to characterize from simple measurements or calculations and is robust.
Speech Intelligibility and Recall of Spoken Material Heard at Different Signal‐to‐noise Ratios and the Role Played by Working Memory Capacity
Authors: Ljung Robert , Israelsson Karl , Hygge Staffan
Published: December 2012

We studied speech intelligibility and memory performance for speech material heard under different signal‐to‐noise (S/N) ratios. Pre‐experimental measures of working memory capacity (WMC) were taken to explore individual susceptibility to the disruptive effects of noise. Thirty‐five participants first completed a WMC‐operation span task in quiet and later listened to spoken word lists containing 11 one‐syllable phonetically balanced words presented at four different S/N ratios (+12, +9, +6, and +3). Participants repeated each word aloud immediately after its presentation, to establish speech intelligibility and later on performed a free recall task for those words. The speech intelligibility function decreased linearly with increasing S/N levels for both the high‐WMC and low‐WMC groups. However, only the low‐WMC group had decreasing memory performance with increasing S/N levels. The memory of the high‐WMC individuals was not affected by increased S/N levels. Our results suggest that individual differences in WMC counteract some of the negative effects of speech noise. Copyright © 2012 John Wiley & Sons, Ltd.
Anakinra in Adult‐Onset Still's Disease: Long‐Term Treatment in Patients Resistant to Conventional Therapy
Authors: Giampietro Cecilia , Ridene Meriem , Lequerre Thierry , Chalumeau Nathalie Costedoat , Amoura Zahir , Sellam Jérémie , Sibilia Jean , Bourgeois Pierre , Fautrel Bruno ,   on behalf of the CRI (Club Rhumatismes et Inflammation)
Published: December 2012

Objective

Anakinra is effective in adult‐onset Still's disease (AOSD) in the short term, but little is known regarding its efficacy over the long term. Our objective was to assess the long‐term efficacy and safety of anakinra in AOSD.

Methods

A nationwide survey was conducted between 2009 and 2010 to identify AOSD patients treated with anakinra. Collected data consisted of disease characteristics at diagnosis and at medication onset; anakinra efficacy, safety, and dose adaptation; and reasons for discontinuation, if applicable.

Results

The study included 28 AOSD patients, with a mean age of 40.3 years and a mean disease duration at the start of anakinra of 9.3 years. All patients had previously failed to respond to steroids and disease‐modifying antirheumatic drugs. All patients responded to anakinra, with a rapid and sustained decrease in steroid doses. At the last followup (mean 23 months), 16 patients were still being treated with anakinra: 4 had a partial response and 12 were in complete remission. Twelve patients had discontinued anakinra: 2 due to an insufficient response, 4 due to an AOSD flare after a period of complete remission, 2 due to side effects, and 1 due to a desire for pregnancy. In 3 patients, the drug discontinuation was possible because they achieved complete remission. Six additional patients experienced anakinra dose tapering, with sustained remission in 2 and relapse in the others. Anakinra was well tolerated and adverse events were rated as mild.

Conclusion

Anakinra was consistently efficacious in AOSD and displayed good therapeutic maintenance. Anakinra dose tapering or discontinuation was associated with relapse in half of the patients.
Characterization of Mixing and Size Segregation in a Rotating Drum by a Particle Tracking Method
Authors: Alizadeh Ebrahim , Dubé Olivier , Bertrand François , Chaouki Jamal
Published: December 2012

The mechanisms of segregation in solids mixing, even in simple rotating drums, are not clearly understood. Although most past studies have focused on binary mixtures, this work investigates the effect of polydispersity on granular flow, mixing, and segregation in a rotating drum operated in rolling regime through particle trajectories obtained from the radioactive particle tracking technique. Velocity profiles, radial segregation, and axial dispersion coefficients for monodisperse and polydisperse systems of glass beads are analyzed with respect to rotational speed and particle size. A model is introduced to predict the residence times along streamlines and evaluate the rate at which the material renews at the free surface and within the inner layers of the bed. Our results reveal similar velocity profiles and residence times for monodisperse and polydisperse systems. They also indicate that the particles distribute along the radial direction of the drum, although not necessarily in a core/shell configuration. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1894–1905, 2013
Temperament in Rhesus, Long‐Tailed, and Pigtailed Macaques Varies by Species and Sex
Authors: SUSSMAN ADRIENNE F. , HA JAMES C. , BENTSON KATHY L. , CROCKETT CAROLYN M.
Published: December 2012

Temperament differs among individuals both within and between species. Evidence suggests that differences in temperament of group members may parallel differences in social behavior among groups or between species. Here, we compared temperament between three closely related species of monkey—rhesus (Macaca mulatta), long‐tailed (M. fascicularis), and pigtailed (M. nemestrina) macaques—using cage‐front behavioral observations of individually housed monkeys at a National Primate Research Center. Frequencies of 12 behaviors in 899 subjects were analyzed using a principal components analysis to identify temperament components. The analysis identified four components, which we interpreted as Sociability toward humans, Cautiousness, Aggressiveness, and Fearfulness. Species and sexes differed in their average scores on these components, even after controlling for differences in age and early‐life experiences. Our results suggest that rhesus macaques are especially aggressive and unsociable toward humans, long‐tailed macaques are more cautious and fearful, and pigtailed macaques are more sociable toward humans and less aggressive than the other species. Pigtailed males were notably more sociable than any other group. The differences observed are consistent with reported variation in these species’ social behaviors, as rhesus macaques generally engage in more social aggression and pigtailed macaques engage in more male–male affiliative behaviors. Differences in predation risks are among the socioecological factors that might make these species‐typical behaviors adaptive. Our results suggest that adaptive species‐level social differences may be encoded in individual‐level temperaments, which are manifested even outside of a social context. Am. J. Primatol. 75:303‐313, 2013. © 2012 Wiley Periodicals, Inc.
Multicomponent and Multimodal Lipsmacking in Crested Macaques (Macaca nigra)
Authors: MICHELETTA JÉRÔME , ENGELHARDT ANTJE , MATTHEWS LEE , AGIL MUHAMMAD , WALLER BRIDGET M.
Published: December 2012

Primates’ communicative signals are often dynamic and composed of multiple components, sometimes belonging to different sensory modalities. Such multicomponent signals are of crucial importance in the study of communication: the addition of extra features to a signal has the potential to modulate or change the meaning and message of the specific signal. Traditionally, however, components of compound signals are studied in isolation from each other, or communicative displays are studied as static and invariant wholes. Both approaches may not allow us to assess the full function of the signals. In crested macaques (Macaca nigra), the lipsmack (a display mainly used in affiliative interactions) can be produced alone or combined with other visual and acoustic communicative features. We investigated whether the composition of the lipsmack influenced the outcome of social interaction while controlling for relationship quality. Our results show that lipsmacks composed of both visual and vocal components (i.e. multimodal signals) increased the probability of affiliative contact, and therefore have enhanced signal value. The total number of visual components involved in the display had no effect but some visual components seemed more influential than others. By analyzing lipsmacking behavior as a composite, dynamic display, we were able to reveal a level of complexity that is not apparent when looking at each component separately. The results highlight the importance of a more integrative, multimodal approach to the study of primate communication. Am. J. Primatol. 75:763–773, 2013. © 2012 Wiley Periodicals, Inc.
Molekulare Allianz – von orthosterischen und allosterischen Liganden zu dualsterischen/bitopischen Agonisten G‐Protein‐gekoppelter Rezeptoren
Authors: Mohr Klaus , Schmitz Jens , Schrage Ramona , Tränkle Christian , Holzgrabe Ulrike
Published: December 2012

Die Zellmembran‐ständigen G‐Protein‐gekoppelten Rezeptoren (GPCRs) gehören zu den wichtigsten therapeutischen Zielstrukturen. Körpereigene Botenstoffe binden von außen an die “orthosterische” Haftstelle in der Tiefe der Bindungstasche oder am extrazellulären N‐terminalen Ende des Rezeptorproteins. Körperfremde Modulatoren, die ein anderes “allosterisches” Haftareal nutzen, ebnen den Weg zu Rezeptorsubtypselektivität. Allerdings ist Rezeptoraktivierung über den orthosterischen Ort häufig besser möglich. Jetzt zeigt sich, dass orthosterisch/allosterische Hybridmoleküle Subtypselektivität und Rezeptoraktivierung vereinen können. Die “bitopischen”/“dualsterischen” Modulatoren vermögen außerdem, den Rezeptor auf eine selektive Anschaltung intrazellulärer Signalwege auszurichten. Dieses Konzept bietet den Zugang zu GPCR‐Modulatoren mit neuartigem Rezeptorsubtyp‐ und Signalwegs‐Selektivitätsprofil und somit zu nebenwirkungsärmeren Wirkstoffen.
Molecular Alliance—From Orthosteric and Allosteric Ligands to Dualsteric/Bitopic Agonists at G Protein Coupled Receptors
Authors: Mohr Klaus , Schmitz Jens , Schrage Ramona , Tränkle Christian , Holzgrabe Ulrike
Published: December 2012

Cell‐membrane‐spanning G protein coupled receptors (GPCRs) belong to the most important therapeutic target structures. Endogenous transmitters bind from the outer side of the membrane to the “orthosteric” binding site either deep in the binding pocket or at the extracellular N‐terminal end of the receptor protein. Exogenous modulators that utilize a different, “allosteric”, binding site unveil a pathway to receptor subtype‐selectivity. However, receptor activation through the orthosteric area is often more powerful. Recently there has been evidence that orthosteric/allosteric, in other words “dualsteric”, hybrid compounds unite subtype selectivity and receptor activation. These “bitopic” modulators channelreceptor activation and subsequent intracellular signaling into a subset of possible routes. This concept offers access to GPCR modulators with an unprecedented receptor‐subtype and signaling selectivity profile and, as a consequence, to drugs with fewer side effects.
AgOTf catalyzed hydration of terminal alkynes
Authors: Das Rima , Chakraborty Debashis
Published: December 2012

The silver catalysis towards the hydration of terminal alkynes is explored using Silver(I) triflate (AgOTf). The reaction leads to the formation of only Markovnikov addition product with excellent yield. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and characterization of a novel precursor‐derived ZrC/ZrB2 ultra‐high‐temperature ceramic composite
Authors: Wang Hao , Chen Xingbo , Gao Bo , Wang Jun , Wang Yingde , Chen Shugang , Gou Yanzi
Published: December 2012

ZrC and ZrB2, two valuable members of ultra‐high‐temperature ceramics (UHTCs), are potentially useful as structural materials in aerospace engineering and hypersonic flight vehicles. This work focused on the preparation of ZrC/ZrB2 UHTC composite by employing a precursor‐derived method. The precursor polymer PZCB was synthesized by the reaction between Cp2Zr(CH═CH2)2 and borane. The composition, structure, element distribution and pyrolysis process of PZCB were investigated by NMR, IR, X‐ray photoelectron spectroscopy, scanning electron microscopy and TGA. The ceramic yield was 50% and the obtained well‐distributed ZrC/ZrB2 ceramic composites had very good high‐temperature resistance. Copyright © 2012 John Wiley & Sons, Ltd.
Numerical simulation of flow and thermal characteristics of harmonic pulsed laminar impinging streams
Authors: Hosseinalipour Mostafa , Esmailpour Kazem , Yahyaee Ali , Mujumdar Arun S.
Published: December 2012

Pulsed jets in various configurations have shown potential for improving transport phenomena. In this study, a system of confined laminar two‐dimensional pulsed impinging streams of air is simulated numerically by solving the governing conservation equations using the control volume method. The key parameters examined in this study are as follows: frequency and amplitude of pulsation, mean jet Reynolds number and phase difference between the nozzle exit velocity profiles. The effects of these parameters are computed and discussed comprehensively. Temperature is used as a passive tracer to quantify the degree of mixing in the system. Results show that flow pulsation has significant effects on the flow field, vortex formation and secondary structures, which are generated. These vortex structures influence the thermal shear layer and improve the mixing behavior. A better mixing index is observed as a result of the formation of larger vortices due to increased amplitude of the pulsation velocity amplitude. In the range of parameters tested, the frequency of the pulsation is found to have negligible effect on the mixing behavior of the system. Also, it is observed that by introducing a phase difference between the two jet velocity profiles, the stagnation point oscillates between the two jets and, in general, the system with phase differences shows better mixing behavior. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Conservation of a permanent hypersaline lake: management options evaluated from decadal variability of Coleofasciculus chthonoplastes microbial mats
Authors: De Wit Rutger , Guerrero Maria‐Carmen , Legaz Alfredo , Jonkers Henk M. , Blocier Laëtitia , Gumiaux Charles , Gautret Pascale
Published: December 2012

‘La Salada de Chiprana’ (NE Spain) is a permanent athalassic saline lake, and as such unique in Western Europe. More than 20 years ago, it was recognized that this lake should be protected; particularly, because it supported extensive microbial mat communities built by the cyanobacterium Coleofasciculus (Microcoleus) chthonoplastes and submerged aquatic vegetation of an endemic form of the foxtail stonewort (Lamprothamnium papulosum var. papulosum f. aragonense).

For centuries, the lake hydrology, salinity and water levels have been driven by the combined effects of anthropogenic activities (e.g. irrigation in the watershed) and climatic factors.

In the early 1990s, the water level increased and salinity dropped as a consequence of excessive freshwater inputs from direct overflow via irrigation canals. As a result, the microbial mats and aquatic vegetation perished and water column turbidity increased. Based on these observations, since 1994 management measures were introduced aimed at reducing the freshwater input by stopping the direct overflow from irrigation canals. This resulted in a rapid recovery of the hypersaline features of the lake, particularly of the microbial mat communities and the aquatic vegetation.

Since 2000, there has been a persistent trend of decreasing lake level and increasing salinity. The population of the endemic foxtail stonewort collapsed in 2006 and the area occupied by C. chthonoplastes mats has drastically decreased. This raises the important question on how to manage athalassic saline lakes in their agrocultural context and calls for a review of the management option taken in the early 1990s. While it could be argued that the current situation is closer to natural hydrological functioning than 20 years ago, we propose that management should seek to conserve the original microbial and aquatic vegetation communities.

Copyright © 2012 John Wiley & Sons, Ltd.
Applying a generic function‐based topical relevance typology to structure clinical questions and answers
Authors: Huang Xiaoli
Published: December 2012

This study investigates the manifestation and utility of a generic function‐based topical relevance typology adapted to the subject domain of clinical medicine. By specifying the functional role of a given piece of relevant information in the overall structure of a topic, the proposed typology provides a generic framework for integrating different pieces of clinical evidence and a multifaceted view of a clinical problem. In medical problem solving structured knowledge plays a key role. The typology provides the conceptual basis for integrating and structuring knowledge; it incorporates and goes beyond existing clinical schemes (such as PICO and illness script) and offers extra assistance for physicians as well as lay users (such as patients and caregivers) to manage the vast amount of diversified evidence, to maintain a structured view of the patient problem at hand, and ultimately to make well‐grounded clinical choices. Developed as a generic topical framework across topics and domains, the typology proved useful for clinical medicine once extended with domain‐specific definitions and relationships. This article reports the findings of using the adapted and extended typology in the analysis of 26 clinical questions and their evidence‐based answers. The article concludes with potential applications of the typology to improve clinical information seeking, organizing, and processing.
Absolute ruin in the compound Poisson model with credit and debit interests and liquid reserves
Authors: Yang Long , He Chuanjiang
Published: December 2012

In this paper, we study the absolute ruin probability in the compound Poisson model with credit and debit interests and liquid reserves. At first, we derive a system of integro‐differential equations with certain boundary conditions for the Gerber–Shiu function. Then, applying these results, we obtain asymptotical formula of the absolute ruin probability for subexponentially claims. Furthermore, when the claims are exponentially distributed, we obtain the explicit expressions for the Gerber–Shiu function and the exact solution for the absolute ruin probability. Finally, we discuss the absolute ruin probability by using the Gerber–Shiu function when debit interest is varying. In the case of exponential individual claim, we give the explicit expressions for the Gerber–Shiu function. Copyright © 2012 John Wiley & Sons, Ltd.
Prüfung der Funktion von Dichtungskontrollsystemen für Konvektionssperren in Deponieoberflächenabdichtungen
Authors: Wöhlecke Andreas , Müller Werner
Published: December 2012

Mit Dichtungskontrollsystemen (DKS) werden Konvektionssperren in Oberflächenabdichtungssystemen von Deponien kontrolliert. Die Funktionsfähigkeit eines eingebauten DKS muss in jedem Projekt zuvor überprüft werden. Diese projektspezifische Funktionsprüfung des DKS selbst wird am Beispiel der Verwendung mit einer Kunststoffdichtungsbahn (KDB) diskutiert. Der grundsätzliche Aufbau, die zugrunde liegenden Messprinzipien und das Ziel der Prüfung werden vorgestellt. Die Anforderungen an die nach der Deponieverordnung (DepV) zugelassenen Systeme hinsichtlich Betrieb, Leitungsfähigkeit und Konstruktion werden beschrieben. Dabei wird auf die Vorgaben der Richtlinie, die einer Zulassung zugrunde liegt, eingegangen. Das mögliche Vorgehen bei der projektspezifischen Kontrollprüfung im Hinblick auf Aspekte wie Vorgehensweise, Zeitpunkt und Randbedingungen sowie äußere Einflussfaktoren werden diskutiert.

Performance test of leak detection systems for tight barriers in landfill covers

Leak detection systems (LDS) are used to control tight barriers in landfill cover systems. However, the efficiency of the installed LDS itself has to be verified in every landfill construction project. As an example the efficiency test for LDS used in connection with geomembranes is discussed in detail. The basic principles, the measuring techniques and objectives of the efficiency testing are described. The requirements for a certification of LDS under the terms of the new German landfill ordinance with regard to operation, capability and design are listed. The conditions necessary for a certification of LDS are introduced. Possible project related efficiency testing procedures with respect to the scope, time of convenience, general conditions as well as external influencing factors are discussed.
Zugelemente aus CFK und ihre Verankerungen
Authors: Schlaich Mike , Zwingmann Bernd , Liu Yue , Goller Ralf
Published: December 2012

Der Fortschritt im Bauingenieurwesen ist eng mit dem Aufkommen neuer Materialien verknüpft. Werkstoffe wie Eisen und Stahl, der moderne Stahlbeton und der Spannbetonbau haben die Baukultur seit dem Beginn der Industrialisierung maßgeblich verändert. Seit den 1990‐er Jahren werden mit Kohlenstofffasern verstärkte Kunststoffe (CFK) für eine steigende Anzahl von Anwendungen im Bauwesen verwendet.

Im Artikel finden sich neben einer Einleitung zu den Eigenschaften dieses Hochleistungswerkstoffs eine Zusammenstellung des Entwicklungsstands von Zugelementen aus CFK und den dazugehörigen Verankerungen. Zugelemente aus CFK haben großes Potenzial für leichte und weitgespannte Konstruktionen wie Seilbrücken und Dachkonstruktionen. Daher wird an der TU Berlin auf dem Gebiet der werkstoffgerechten Ausbildung von CFK‐Zugelementen geforscht.

CFRP Tension Elements and Their Anchorages

Progress in civil engineering is highly connected to the appearance of new materials. The materials iron and steel, reinforced concrete and prestressed concrete have been influencing the building culture since the beginning of industrialization. From the 1990s carbon fiber reinforced plastics (CFRP) experience an increasing use for structural application.

This article gives an introduction to the properties of this high‐performance material and presents the state of the art of CFRP tension elements with their corresponding anchorages. CRFP tension elements have high potential for lightweight and wide spread constructions like cable bridges and suspended roofs. Therefore the appropriate design regarding the material of CFRP tension elements is investigated at the Technical University of Berlin.
Zum Einfluss der Belastungsfrequenz und der Spannungsgeschwindigkeit auf die Ermüdungsfestigkeit von Beton
Authors: Schneider Sebastian , Vöcker Daniela , Marx Steffen
Published: December 2012

Die Ermüdungseigenschaften von Beton werden in den meisten Fällen mithilfe sogenannter Einstufenversuche untersucht. Dabei wird eine Betonprobe mit einer konstanten Mittellast beaufschlagt, der nachfolgend eine oszillierende Schwingbeanspruchung überlagert wird. Um den Zeitaufwand für diese Versuche zu minimieren, wird eine möglichst hohe Belastungsfrequenz angestrebt. Allerdings wurde durch einige Forschungsarbeiten deutlich, dass die Belastungsfrequenz einen Einfluss auf die ertragbaren Lastwechsel von Beton hat. Die Auswertung von in der Literatur dokumentierten Versuchen ergab, dass die Ermüdungsfestigkeit, analog zur Betondruckfestigkeit bei einmaliger Belastung, scheinbar maßgeblich von der Dehngeschwindigkeit abhängt. Diese Erkenntnis erlaubt zum einen eine relativ einfache Umrechnung von Versuchsergebnissen, die mit hohen Prüffrequenzen gewonnen wurden. Zum anderen kann damit eine Grenzfrequenz für Ermüdungsversuche in Abhängigkeit von der Schwingbreite bestimmt werden.

About loading frequency and stress rate influences on fatigue strength of concrete

The fatigue behavior of concrete is mostly studied on the basis of constant amplitude tests. Constant maximum and minimum stresses are applied to concrete specimens during these tests. In addition, high loading frequencies are used in order to minimize the test duration. However, the loading frequency has an influence on the number of load cycles to failure. A study of fatigue tests documented in the literature has shown that the fatigue strength of concrete depends on the strain rate like the compressive strength due to single loading. With this consideration it becomes possible to convert test results with different loading frequencies into each other. Furthermore, a frequency limit can be determined depending on the stress range.
Analyse der durch Frost‐ und Frost‐Tausalz‐Wechsel induzierten Schädigungsprozesse in Beton
Authors: Weise Frank , Maier Bärbel , Ehrig Karsten
Published: December 2012

Zur Beurteilung des Frost‐ bzw. Frost‐Tausalz‐Widerstandes des Betons finden normativ als Alternativverfahren das CIF‐ bzw. CDF‐Verfahren Anwendung. Als Beurteilungskriterium für den inneren Schädigungsprozess werden bisher ausschließlich die Änderung der Ultraschalllaufzeit und die Massezunahme durch Frostsaugen herangezogen. Die Bewertung des äußeren Schädigungsprozesses hingegen erfolgt ausschließlich mittels einer vergleichenden visuellen Beurteilung der Prüffläche und der Ermittlung der Abwitterungsmasse. Allen bisher angewandten inneren und äußeren Schädigungsindikatoren ist gemeinsam, dass ihre Aussagefähigkeit durch eine fehlende ortsaufgelöste Quantifizierung des Schädigungsprozesses eingeschränkt ist.

Der Beitrag zeigt, dass dieser Nachteil durch den Einsatz neuartiger innovativer Prüftechniken weitestgehend beseitigt werden kann. So wird vergleichend zu der normativen Ultraschallprüfung aufgezeigt, dass der Einsatz der Röntgen 3D‐Computertomografie eine zerstörungsfreie zeitliche und räumliche Analyse des inneren Rissbildungsprozesses beim CIF‐Verfahren ermöglicht. Außerdem wurde durch die Anwendung der Photogrammetrie die äußere Abwitterung der Prüffläche beim CDF‐Verfahren erstmalig ortsaufgelöst quantifiziert.

Analysis of damage processes in concrete induced by freeze thaw or freeze thaw salt cycles. Application of innovative measurement techniques

CIF‐ and CDF‐test are alternatively applied for the standardized assessment of freeze and freeze de‐icing salt resistance of concrete. Up to now the increase of ultrasonic time of flight and mass induced by freeze suction are the only criteria for the assessment of internal damage process. The evaluation of the external damage process is currently realised by visual comparison of test surfaces and the determination of the scaling mass. The significance of these internal and external damage indicators is limited due to the lack of spatially‐resolved quantifications of the damage process.

This contribution shows that this disadvantage can be overcome by the application of innovative test methods. In contrast to normative ultrasound test methods, the application of X‐ray 3D computed tomography allows a non‐destructive temporal and spatial analysis of the internal crack formation process during the CIF‐test. For the first time, a spatially‐resolved quantification of the scaling of the test surface has been performed by photogrammetry.
Leichte Stahlbetontragwerke mit großen Spannweiten
Authors: van Berkel Ben , Steller Frank
Published: December 2012

Die offene transparente Bauweise des Zentrums für Virtuelles Engineering erforderte den Einsatz leichter Konstruktionen mit großen Spannweiten. Die Anforderungen an den Entwurf werden einleitend aus der Sicht des Architekten dargestellt. Anschließend werden die Schritte vom architektonischen zum konstruktiven Entwurf beschrieben. Auf die Erfahrungen mit den eingesetzten leichten Bauweisen wird ausführlich aus dem Blickwinkel des planenden Ingenieurs eingegangen.

Centre for Virtual Engineering of the Fraunhofer Institute in Stuttgart‐Vaihingen. Light‐weight reinforced concrete structures with large spans

The opened and transparent construction of the Centre for Virtual Engineering required the application auf light‐weight structures with large spans. In the beginning the draft requirements are shown from the architect's viewpoint. Afterwards the steps from the architectural to the structural concept are described. In detail they dwell on the engineer's experience with the applied light‐weight constructions.
Interval estimation of the mean difference in the analysis of over‐dispersed count data
Authors: Saha Krishna K.
Published: December 2012

This paper focuses on the development and study of the confidence interval procedures for mean difference between two treatments in the analysis of over‐dispersed count data in order to measure the efficacy of the experimental treatment over the standard treatment in clinical trials. In this study, two simple methods are proposed. One is based on a sandwich estimator of the variance of the regression estimator using the generalized estimating equations (GEEs) approach of Zeger and Liang (1986) and the other is based on an estimator of the variance of a ratio estimator (1977). We also develop three other procedures following the procedures studied by Newcombe (1998) and the procedure studied by Beal (1987). As assessed by Monte Carlo simulations, all the procedures have reasonably well coverage properties. Moreover, the interval procedure based on GEEs outperforms other interval procedures in the sense that it maintains the coverage very close to the nominal coverage level and that it has the shortest interval length, a satisfactory location property, and a very simple form, which can be easily implemented in the applied fields. Illustrative applications in the biological studies for these confidence interval procedures are also presented.
Patterns and predictive factors of complications after endoscopic retrograde cholangiopancreatography
Authors: Glomsaker T , Hoff G , Kvaløy J T , Søreide K , Aabakken L , Søreide J A
Published: December 2012

Background

With an increased use of magnetic resonance imaging, the indications for endoscopic retrograde cholangiopancreatography (ERCP) have changed. Consequently, the patterns and factors predictive of complications after ERCP performed during current routine clinical practice are not well known.

Methods

A prospective multicentre cohort study was undertaken in 11 Norwegian hospitals. Complications and mortality within 30 days after ERCP were analysed by univariable and multivariable regression analysis.

Results

There were 2808 ERCP procedures, of which 2573 (91·6 per cent) were therapeutic. More than half of the patients were aged 70 years or more. Common bile duct cannulation was achieved in 2557 procedures (91·1 per cent). Complications occurred in 327 (11·6 per cent) of the procedures, including cholangitis in 100 (3·6 per cent), pancreatitis in 88 (3·1 per cent), bleeding in 66 (2·4 per cent), perforation in 25 (0·9 per cent) and cardiovascular–respiratory events in 32 (1·1 per cent). In the multivariable regression analysis, older age, increasing American Society of Anesthesiologists fitness score, centre ERCP volumes of more than 150 procedures annually and precut sphincterotomy were predictive factors for severe complications. The overall 30-day mortality rate was 2·2 per cent (63 patients), with a procedure-related mortality rate of 1·4 per cent (39 patients). Malignancy was diagnosed in 46 (73 per cent) of the patients who died.

Conclusion

ERCP is a procedure with considerable risk for complications. Morbidity and mortality are related to patient age and co-morbidity, as well as hospital volume of ERCP procedures and the type of intervention.
Simultaneous determination of homocysteine, methionine and cysteine in maternal plasma after delivery by HPLC‐fluorescence detection with DBD‐F as a label
Authors: Wada Mitsuhiro , Hirose Maki , Kuroki Mana , Ikeda Rie , Sekitani Yui , Takamura Noboru , Kuroda Naotaka , Nakashima Kenichiro
Published: December 2012

An HPLC‐fluorescence (FL) method for determination of sulfur‐containing amino acids such as homocysteine (Hcy), methionine (Met) and cysteine (Cys) in human plasma was developed. The sulfur‐containing amino acids were labeled with 4‐(N,N‐dimethylaminosulfonyl)‐7‐fluoro‐2,1,3‐benzoxadiazole (DBD‐F). Calibration curves in the range of 1–100 µm (Hcy and Met) and 5–500 µm (Cys) indicated good linearities (r ≥ 0.998). The limits of detection at a signal‐to‐noise ratio of 3 were 0.13 (Hcy), 0.02 (Met) and 0.11 µm (Cys), respectively. Acceptable results for accuracy and precision of intra‐ and inter‐day measurements were obtained. The results of Hcy and Cys obtained by the proposed method indicated good correlations with the conventional method (r > 0.911, n = 20). Furthermore, the method was applied to determination of the sulfur‐containing amino acids in maternal plasma (n = 200) after delivery. The concentrations of Hcy, Met and Cys as a median (inter quartile range, Q1 and Q3) were 5.37 (3.32–7.79) μm, 25.20 (20.10–31.06) μm and 147.25 (102.81–189.31) μm, respectively. Copyright © 2012 John Wiley & Sons, Ltd.
Enhanced protein stability through minimally invasive, direct, covalent, and site‐specific immobilization
Authors: Smith Mark T. , Wu Jeffrey C. , Varner Chad T. , Bundy Bradley C.
Published: December 2012

Bioconjugating protein to nonbiological surfaces is an essential component of many promising biotechnologies impacting diverse applications such as medical diagnostics, biocatalysis, biohazard detection, and proteomics. However, to enable the widespread economical use of immobilized‐protein technologies, long‐term stability, and reusability is essential. To enhance protein stability in harsh conditions, herein we report a minimally invasive and covalent bioconjugation that enables precise control of the immobilization location at potentially any surface‐accessible location where the incorporated unnatural amino acid does not impact protein structure and function. Specifically, the PRECISE system is introduced where a uniquely reactive unnatural amino acid was incorporated site‐specifically at a prespecified location in GFP using cell‐free protein synthesis. The GFP was then directly and covalently attached to superparamagnetic beads by the unnatural amino acid in a single click reaction. The immobilized GFP was probed for retained activity and stability under harsh conditions including freeze‐thaw cycling and incubation in urea at elevated temperatures. The immobilized GFP was more stable compared to unattached protein in all cases and for all durations observed. The enhanced stability of the immobilized protein is a promising step towards long‐term protein stability for biocatalysis and other immobilized‐protein applications. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Counter‐Rotating Spin‐Polarised Ring Currents in Odd‐Electron Carbocycles
Authors: Soncini Alessandro , Fowler Patrick W.
Published: December 2012

We propose a molecular‐orbital model to explain how majority and minority spins in odd‐π‐electron carbocycles sustain counter‐rotating magnetic‐field‐induced ring currents. The model is based on the ipsocentric approach to magnetic response, in which ring currents are dominated by frontier‐orbital contributions obeying angular‐momentum selection rules. Coupled unrestricted Hartree–Fock ab initio calculations of the ring‐current responses for singly charged benzene and planarised cyclo‐octatetraene ions confirm the predictions of the qualitative model, and are consistent with correlated MP2 spin‐polarised current calculations.
Einem Leib‐ und Magenfeind zum Abschied
Authors: Roth Klaus
Published: December 2012

Mehr als die Hälfte der Weltbevölkerung ist mit Helicobacter pylori infiziert. Meistens führt der ungeladene Gast in unserem Magen ein ruhiges Leben, aber er kann auch eine Menge Ärger machen. Um in einer Umgebung mit pH = 1 zu überleben, hat er eine glänzende Strategie entwickelt, um mit der übermächtigen Salzsäure zurechtzukommen. Seine Hauptwaffen sind die Säure‐Base‐Theorie und eine potente Urease. Dieses Enzym hydrolysiert Harnstoff zu Ammoniak und Kohlendioxid, die H. pylori helfen, um sich herum den pH auf verträgliche Werte zu halten. Um H. pylori loszuwerden, nutzen auch wir die Säure‐Basen‐Therorie plus Antibiotika und pfiffige Methoden, um den Therapieerfolg zu überprüfen. Auch wenn wir die Schlacht gewonnen haben, müssen wir trotzdem zugeben, dass H. pylori ein bemerkenswerter Chemiker ist und unseren Respekt verdient hat.
Co‐composting of Municipal Solid Waste with Sawdust: Improving Compost Quality
Authors: Yousefi Javad , Younesi Habibollah , Ghasempoury Seyed Mahmoud
Published: December 2012

The aim of present study was to improve compost quality as well as to achieve an optimum C/N ratio in compost, reduction in heavy metal content and increased water‐holding capacity of composting piles in arid areas. Four windrow compost piles were prepared by mixing sawdust at various dosages with municipal solid waste (MSW). The sawdust was mixed with MSW at 0% (MSW0), 16% (MSW16), 32% (MSW32), and 70% (MSW70) on dry weight basis. The compost piles were monitored daily by recording the temperature, while, weekly measurement was done on C/N ratio, moisture, pH, and electrical conductivity (EC). The addition of 16% sawdust increased the initial C/N to the optimum level and decreased N loss during the composting process. The MSW16 and MSW32 exhibited better temperature dynamics and their composting period seemed to be shorter than that of MSW0 and MSW70. Moreover, addition of sawdust caused lowering of moisture loss from the composting piles. Sawdust admixtures also produced lowering of pH and EC values and led to lower heavy metal content in final products. The quality of the final compost makes it possible to propose the use of this experimental procedure for building up a novel mass reduction of the initial composted waste mixtures.
Identification and Apportionment of Sources of Ozone‐forming Potential for Proper Reduction Strategies
Authors: Demir Selami , Saral Arslan
Published: December 2012

In this study, results of source identification and apportionment for ambient volatile organic compounds (VOCs) from a previous work were used to estimate ozone‐forming potentials (OFPs) of effective sources for developing proper strategies for reduction of tropospheric ozone pollution. The source identification and apportionment of ambient VOC pollution within Yildiz Technical University's Davutpasa Campus (Istanbul, Turkey) was done by positive matrix factorization (PMF). The results suggested five effective source groups with the emissions related with paint use and solvent use having the highest contributions (36.8 and 28.2%). The results from PMF were used along with maximum incremental reactivities to estimate potentials of individual sources for ozone formation. It was found that biogenic emissions (3.78) and traffic related emissions (gasoline and diesel vehicle exhaust) (3.83 and 3.15, respectively) have the highest potential for ozone formation in terms of grams O3/g VOC emitted. The results were used to suggest proper source‐based reduction strategies for OFP.
Adsorption of Thallium(I) Ions Using Eucalyptus Leaves Powder
Authors: Dashti Khavidaki Hossein , Aghaie Hossein
Published: December 2012

Using batch method, the adsorption of thallium(I) ions from aqueous solutions on eucalyptus leaves powder, as a low cost adsorbent, was studied. The effect of various modification of considered adsorbent on the adsorption percentage of Tl(I) is an important feature of this study. The results showed that the unmodified and acidic modified adsorbent are the poor adsorbents for the Tl(I) ions while basic modified adsorbent is a suitable adsorbent. Also, the effect of some experimental conditions such as solution initial pH, agitation speed, contact time, sorbent dosage, temperature, particle size, and thallium initial concentration was studied. The results showed that the adsorption percentage depends on the conditions and the process is strongly pH‐dependent. The satisfactory adsorption percentage of Tl(I) ions, 81.5%, obtained at 25 ± 1°C. The equilibrium data agreed fairly better with Langmuir isotherm than Freundlich and Temkin models. The value of qm that was obtained by extrapolation method is 80.65 mg g−1. Separation factor values, RL, showed that eucalyptus leaves powder is favorable for the sorption of Tl(I). The negative values of ΔH0 and ΔS0 showed that the Tl(I) sorption is an exothermic process and along with decrease of randomness at the solid–solution interface during sorption, respectively.
Morphology‐controlled CaMoO4 nanorods via a facile microwave‐assisted EDTA chelating agent process
Authors: Wang Lina , Sun Yan , Li Chunsheng , Wang Yaozu , Ma Xuegang , Wang Yandi , Li Shuoshuo , Zhang Zhijia , Ma Peijuan , Cui Guanghua
Published: December 2012

This work reports on the shape‐controlled synthesis of CaMoO4 nanorods via a high‐efficient microwave irradiation‐assisted chelating agent method. The phase and microstructure of these materials were systematically characterized by X‐ray diffraction and field‐emission scanning electron microscopy. It is noteworthy that EDTA plays pivotal roles as the complexing and capping agent in the oriented growth of uniform CaMoO4 nanorods. The synthetic process gives the guidance to understand the morphological evolution of CaMoO4 microstructures in microwave system, and provides a facile and designed strategy to fabricate functional one dimensional metallic molybdates.
Crystal growth and spectral properties of Nd:Ca5(BO3)3F
Authors: Xia Mingjun , Li R. K.
Published: December 2012

A neodymium doped Ca5(BO3)3F single crystal with size up to 51×48×8 mm3 has been grown by the top seeded solution growth (TSSG) technique with a Li2O‐B2O3‐LiF flux. The spectra of absorption and fluorescence were measured at room temperature. According to Judd‐Ofelt (J‐O) theory, the spectroscopic parameters were calculated and the J‐O parameters Ω2, Ω4, Ω6 were obtained as follows: Ω2 = 1.41×10−20cm2, Ω4 = 3.18×10−20cm2, Ω6 = 2.11×10−20cm2. The room temperature fluorescence lifetime of NCBF was measured to be 51.8 μs. According to the J‐O paramenters, the emission probabilities of transitions, branching ratios, the radiative lifetime and the quantum efficiency from the Nd3+ 4F3/2 metastable state to lower lying J manifolds were also obtained. In comparasion with other Nd‐doped borate crystals, the calculated and experimental parameters show that NCBF is a promising SFD crystal.
Boron‐doped Homoepitaxial Diamond CVD from Microwave Plasma‐Activated Ethanol/Trimethyl Borate/Hydrogen Mixtures
Authors: Belousov Maxim E. , Mankelevich Yuri A. , Minakov Pavel V. , Rakhimov Alexander T. , Suetin Nikolay V. , Khmelnitskiy Roman A. , Tal Alexei A. , Khomich Alexander V.
Published: December 2012

Boron‐doped homoepitaxial diamond films are deposited from ethanol/trimethyl borate/hydrogen mixtures activated by microwave (MW) discharge plasma. The high smoothness, uniform distribution of boron atoms located predominantly in substitution positions, and low concentration of the nitrogen‐compensating impurity is achieved. C2H5OH dissociation pathways in MW plasma‐activated (PA)CVD reactor conditions, and the distribution of CxHyOz concentrations in the hot core of C2H5OH/H2 plasma are calculated. It is shown that the methyl radical is as responsible for diamond growth in C2H5OH/H2 mixtures as for a conventional CH4/H2 mixture.