bluuebunny/crossref_metadata_2025 huggingface dataset:
bauma 2013 – Plattform für Neuheiten
Authors: Richter Helmut
Published: April 2013

Vom 15. bis 21. April 2013 öffnet die weltgrößte Baumaschinenmesse wieder ihre Pforten und erwartet in München einen hohen Besucherstrom aus der ganzen Welt. Die bauma 2013, Internationale Fachmesse für Baumaschinen, Baustoffmaschinen, Bergbaumaschinen, Baufahrzeuge und Baugeräte, findet dieses Jahr zum 30. Mal statt. Über 3.300 Aussteller präsentieren auf einer erweiterten Ausstellungsfläche von 570.000 m2 neue und bewährte Produkte der internationalen Bau‐, Baustoff‐ und Bergbaumaschinenindustrie.

Obwohl die Flächenkapazitäten gegenüber 2010 noch einmal erweitert wurden, ist die bauma einmal mehr an ihre Grenzen gestoßen. Die Wartelisten sind noch immer lang, die Messemacher konnten erneut nicht alle Teilnahmewünsche erfüllen. Die Anziehungskraft dieser Veranstaltung ist international ohne gleichen. Sie ist nicht nur die größte Bau‐ und Baustoffmaschinenmesse der Welt, sondern auch die, auf der die meisten Weltneuheiten zu sehen sind. Effizienz, Umweltverträglichkeit und Arbeitssicherheit werden einige der vorherrschenden Themen sein. Dass sie mehr als nur neue Impulse für die Geschäftsentwicklungen gibt, davon geht Joachim Schmid, Geschäftsführer des Fachverbands Bau‐ und Baustoffmaschinen aus: “Die bauma ist mehr – sie ist der Gradmesser für die zukünftige Marktentwicklung”.

bauma 2013 – Platform for innovations. The largest exhibition of construction machinery in the world will open its doors from 15 to 21 April 2013 in Munich and expects a flood of visitors from all over the world. bauma 2013, the International Trade Fair for Construction Machinery, Building Material Vehicles, Mining Machines, Construction Vehicles and Construction Equipment, is taking place for the 30th time this year. Over 3,300 exhibitors will be presenting new and proven products of the international construction, construction materials and mining machinery industry in an enlarged area of 570,000 m2.

Although the available area has again been increased compared to 2010, the bauma has once again met its limits. The waiting lists are still long and the organisers could once again not satisfy all the demand for space. The pulling power of this event is international like no other. It is not only the largest event for construction and construction materials machinery, but also where the most worldwide innovations are to be seen. Efficiency, environmental compatibility and occupational safety will be some of the main themes. The event provides more than just new impulses for business development, states Joachim Schmid, managing director of the construction and construction machinery association: “the bauma is more – it is the indicator of future market development”.
A note on the upper bound in SA AMG convergence analysis
Authors: Guo Cui , Xiang Hua
Published: April 2013

In [M. Brezina, P. Vaněk and P. S. Vassilevski, An improved convergence of smoothed aggregation algebraic multigrid, Numer. Linear Algebra Appl., 19 (2012), pp. 441–469], a uniform convergence bound for smoothed aggregation algebraic multigrid with aggressive coarsening and massive polynomial prolongator and multigrid smoothers is established provided that the number of smoothing steps is equal to the coarsening ratio parameter ν. The final convergence estimate needs the uniform bound for the constant Cν ∕ (2ν + 1). In this note, we give an improved upper bound. Copyright © 2013 John Wiley & Sons, Ltd.
Discontinuous Galerkin and multiscale variational schemes for a coupled damped nonlinear system of Schrödinger equations
Authors: Asadzadeh M. , Rostamy D. , Zabihi F.
Published: April 2013

In this article, we study a streamline diffusion‐based discontinuous Galerkin approximation for the numerical solution of a coupled nonlinear system of Schrödinger equations and extend the resulting method to a multiscale variational scheme. We prove stability estimates and derive optimal convergence rates due to the maximal available regularity of the exact solution. In the weak formulation, to make the underlying bilinear form coercive, it was necessary to supply the equation system with an artificial viscosity term with a small coefficient of order proportional to a power of mesh size. We justify the theory by implementing an example of an application of the time‐dependent Schrödinger equation in the coupled ultrafast laser. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Variable characteristics with insulin assays
Authors: Kalathil S , Napier C , Pattman SJ , Wark G , Abouglila K , James RA
Published: April 2013

Factitious hypoglycaemia is a challenging diagnosis to confirm. Evaluation of surreptitious human insulin use can be distinguished from endogenous insulin excess by existing biochemical assays. However, the increasing use of insulin analogues poses a challenge because commercially available insulin assays detect these with varying accuracy and precision.

Insulin analogues are increasingly used in diabetes management and the case outlined here highlights the variations in assay. Initially, the local assay (ELISA kit – Dako, Copenhagen) failed to detect a significant concentration of insulin (<6pmol/L; range 9.6–65.4pmol/L) which an external reference laboratory subsequently detected using the Mercodia Iso‐insulin two‐site immunoassay (Uppsala, Sweden).

The key analytical point is the recognition that different immunoassays detect insulin analogues to varying degrees. Clinical teams need to consider this if such cases are to be recognised. Following recent media reports where surreptitious insulin administration may be implicated in inpatient mortality, this knowledge is crucial to empower us to accurately diagnose all cases of unexplained hypoglycaemia. Copyright © 2013 John Wiley & Sons. Practical Diabetes 2013; 30(3): 118–120
Preanalytical sample handling of venous blood: how to ensure your glucose measurement is accurate and reliable
Authors: Steele AM , Wensley KJ , Brewer E , Shields BM , Hattersley AT , McDonald TJ
Published: April 2013

Measurement of blood glucose is a standard biochemical test requiring optimum preanalytical sample handling. Glucose measured in plasma from tubes containing sodium fluoride is recommended but serum from serum‐gel tubes may be used in research situations. To help inform best practice, we assessed glucose stability in plasma and serum samples subjected to different preanalytical conditions.

Fasting samples were taken from 10 non‐diabetic volunteers into fluoride/EDTA and serum‐gel tubes. Whole blood samples were pipetted into aliquots, placed on crushed ice or left at room temperature. Aliquots were centrifuged at 0, 2, 12, 24, and 48 hours.

When neither ice nor centrifuge were available, plasma glucose was stable for 48 hours (96% of baseline); serum glucose degraded to 8% of baseline. When centrifuged and left at room temperature, plasma glucose was stable for 48 hours (101% of baseline) but, by 24 hours, serum glucose had fallen (94% of baseline). The result of un‐centrifuged plasma on ice was stable (96% of baseline) at 48 hours; serum glucose had dropped to 92% of baseline by 12 hours. Plasma glucose and serum glucose were constant for 48 hours when separated and placed on ice within 2 hours: plasma glucose 101% of baseline; serum glucose 100% of baseline. Separated serum resting on the serum plug fell to 94% of baseline by 12 hours at room temperature and to 92% of baseline by 48 hours on ice.

Clinically, we recommend that glucose is measured on plasma taken from fluoride tubes. Analysis should be undertaken as soon as practicable. In the research setting, glucose can be measured on plasma or serum but samples must be centrifuged and chilled soon after venepuncture and analysed within 48 hours. Copyright © 2013 John Wiley & Sons. Practical Diabetes 2013; 30(3): 128–131
Obesity co‐morbidities and the obesity paradox
Authors: Haslam David
Published: April 2013

It is no surprise that obesity is associated with co‐morbidities including diabetes, cardiovascular disease, obstructive sleep apnoea and cancer, and that weight loss confers protection against their onset. Therefore it is counter‐intuitive that, although obesity is implicated in their cause, its presence seems to be protective against mortality once some of these conditions have occurred. ‘The idea that a known risk factor somehow transforms into a “protective” agent after an occurrence of a vascular clinical event is both surreal and troubling’.1 This phenomenon has been termed the ‘obesity paradox’ by many authorities.

This article discusses the link between obesity and various long‐term illnesses, assesses the evidence surrounding the obesity paradox, and considers whether weight reduction, or the alternative – obesity‐related risk management while weight is maintained – is an appropriate goal in the elderly and in the presence of certain medical conditions. Copyright © 2013 John Wiley & Sons. Practical Diabetes 2013; 30(3): 132–135
Characterization of nickel nanostrand nanocomposites through dielectric spectroscopy and nanoindentation
Authors: Koecher Michael , Yeager John D. , Park Tyler , Fullwood David , Colton John S. , Mara Nathan , Hansen Nathan
Published: April 2013

One particularly promising model of electrical properties of conductive nanocomposites involves a combined quantum tunneling/percolation approach. However, two key inputs to the model—the polymer matrix barrier height and the average gap between conductive filler particles—are difficult to determine experimentally. This article demonstrates improved methods for determining barrier height in polymer materials via conductive nanoindentation, with barrier heights measured between 0.4 and 1.7 eV for five different polymers. By using dielectric spectroscopy techniques, combined with the barrier height measurements, the average junction gap was determined for the first time for nickel‐nanostrand nanocomposites with six different polymer matrices; the values range from 1.31 to 3.28 nm. Using those measured values for barrier height and junction gap distances in a simple model, we have tested predictions for bulk resistivity of six polymers. The model worked well for four of the six, which suggests that for a given volume fraction of filler, knowledge of the barrier height and the junction distance may in many cases be sufficient to provide an estimate of the bulk resistivity of the polymer‐nanostrand blend, an important parameter in nanocomposite engineering. POLYM. ENG. SCI., 53:2666–2673, 2013. © 2013 Society of Plastics Engineers
Effect of Intravenous Zanamivir on Cardiac Repolarization
Authors: Lou Yu , Gan Jianjun , Peppercorn Amanda , Gould Elizabeth , Weller Steve , Piscitelli Stephen C. , Patel Parul
Published: April 2013

Study Objective

To assess the effect of a therapeutic and supratherapeutic intravenous dose of the neuraminidase inhibitor zanamivir onQTand rate‐correctedQTintervals.

Design

Randomized, placebo‐controlled, single‐dose, four‐period, balanced crossover study.

Setting

Clinical research unit.

Subjects

Forty healthy adults were randomized to receive intravenous zanamivir at two dose levels, oral moxifloxacin, and placebo; 38 subjects completed all four study treatments.

Intervention

Subjects were randomized to receive a single intravenous dose of zanamivir 600 mg (therapeutic dose) with oral moxifloxacin placebo, a single intravenous dose of zanamivir 1200 mg (supratherapeutic dose) with oral moxifloxacin placebo, oral moxifloxacin 400 mg (positive control) with intravenous zanamivir placebo, or intravenous zanamivir placebo with oral moxifloxacin placebo. Subjects crossed over to all other treatments, with each treatment separated by a 7‐day washout period.

Measurements and Main Results

Zanamivir pharmacokinetics were dose proportional; the pharmacokinetic exposure from zanamivir 1200 mg was 2 times higher than that from 600 mg, the maximum dose under clinical evaluation. For both 600‐mg and 1200‐mg doses of intravenous zanamivir, the upper limit of the 90% confidence interval (CI) for the placebo‐adjusted mean change from baseline of theQTinterval corrected for heart rate using Fridericia's formula (ΔΔQTcF) was less than 10 msec at all time points. The sensitivity of the study to detect modest increases inQTinterval was established with the positive control, moxifloxacin. The maximum ΔΔQTcF value for zanamivir 1200 mg was 1.73 msec (90%CI–0.40 to 3.87 msec), which was observed within 30 minutes after dosing, and 11.21 msec (90% CI8.81–13.60) for moxifloxacin, observed at 4 hours after dosing. No relationship was observed between zanamivir serum concentration and ΔΔQTcF. Zanamivir was generally well tolerated, with very few adverse events; none were serious or severe.

Conclusion

Intravenous zanamivir does not affect cardiac repolarization. Accordingly, treatment with intravenous zanamivir does not require additional cardiac monitoring beyond the standard of care.
Thermokarst Processes and Depositional Events in a Tundra Lake, Northeastern Siberia
Authors: Biskaborn Boris K. , Herzschuh Ulrike , Bolshiyanov Dmitry Y. , Schwamborn Georg , Diekmann Bernhard
Published: April 2013

The relationships between thermokarst activity, limnogeological processes and climate change in the Siberian Arctic are not well understood. The objective of this paper is to identify the factors controlling the patterns of deposition, using grain size distribution, organic content, elemental composition and mineralogical composition of a 137‐cm long sediment core with a maximum age of ~ 10.9 cal. kyr BP from Lake El'gene‐Kyuele in the tundra of northeastern Siberia. Eight fine sand layers are attributed to depositional events associated with thaw slump activity acting upon orthogonally oriented patterns of ice‐wedge networks in the ice‐rich permafrost on the NW margin of the lake catchment. Sr/Rb ratios, which correspond to the total feldspar and illite content, serve as high‐resolution grain size proxies. The Br content relates to the total organic carbon content, and the Fe/Mn ratio reflects the degree of oxidisation. Our results indicate a relationship between repeated phases of fine sand input and retrogressive thaw slumping dependent on hydroclimate variability and orthogonally oriented ice‐wedge networks within the catchment. Copyright © 2013 John Wiley & Sons, Ltd.
Incorporating into a Cα Go model the effects of geometrical restriction on Cα atoms caused by side chain orientations
Authors: Sugita Masatake , Kikuchi Takeshi
Published: April 2013

Coarse‐grained Go models have been widely used for studying protein‐folding mechanisms. Despite the simplicity of the model, these can reproduce the essential features of the folding process of a protein. However, it is also known that side chains significantly contribute to the folding mechanism. Hence, it is desirable to incorporate the side chain effects into a coarse‐grained Go model. In this study, to distinguish the effects of side chain orientation and to understand how these effects contribute to folding mechanisms, we incorporate into a Cα Go model not only heterogeneous contact energies but also geometrical restraints around two Cα atoms in contact with each other. We confirm that the heterogeneity of contact energies governs the folding pathway of a protein and that the geometric constraints attributed to side chains reproduce cooperative transitions in folding. Proteins 2013; 81:1434–1445. © 2013 Wiley Periodicals, Inc.
Folding of Top7 in unbiased all‐atom Monte Carlo simulations
Authors: Mohanty Sandipan , Meinke Jan H. , Zimmermann Olav
Published: April 2013

For computational studies of protein folding, proteins with both helical and β‐sheet secondary structure elements are very challenging, as they expose subtle biases of the physical models. Here, we present reproducible folding of a 92 residue α/β protein (residues 3–94 of Top7, PDB ID: 1QYS) in computer simulations starting from random initial conformations using a transferable physical model which has been previously shown to describe the folding and thermodynamic properties of about 20 other smaller proteins of different folds. Top7 is a de novo designed protein with two α‐helices and a five stranded β‐sheet. Experimentally, it is known to be unusually stable for its size, and its folding transition distinctly deviates from the two‐state behavior commonly seen in natural single domain proteins. In our all‐atom implicit solvent parallel tempering Monte Carlo simulations, Top7 shows a rapid transition to a group of states with high native‐like secondary structure, and a much slower subsequent transition to the native state with a root mean square deviation of about 3.5 Å from the experimentally determined structure. Consistent with experiments, we find Top7 to be thermally extremely stable, although the simulations also find a large number of very stable non‐native states with high native‐like secondary structure. Proteins 2013; 81:1446–1456. © 2013 Wiley Periodicals, Inc.
Normalization of process safety lagging metrics
Authors: Wang Mengtian , Mentzer Ray A. , Gao Xiaodan , Richardson Joshua , Mannan M. Sam
Published: April 2013

This article explores new process safety metrics for measuring process safety performance in the chemical processing industry. While Process Safety Management enables an operation to optimize their process safety programs and organizational risks, there is an emerging need to evaluate process safety implementation across an organization through measurement of key indicators. Lagging metrics utilize process safety incidents as the numerator and divide it by an appropriate process‐related denominator or “normalization factor.” Currently, work hours is used extensively as a normalization factor to evaluate safety performance in the process industries. However, this lagging metric does not directly reflect process safety information and may not accurately reflect the safety performance of the process. Modified denominators are explored in this study and compared with the existing time‐based denominator to validate the effectiveness and applicability of the new metrics. Each proposed normalization factor was validated using available industry data. A statistical unitization method has been used to convert incident rates of different ranges for the convenience of comparison. Results show that some proposed process‐related metrics have potential as alternatives, used along with the time‐based metric, to evaluate process safety performance within organizations. © 2013 American Institute of Chemical Engineers Process Saf Prog 32: 337–345, 2013
Determinants of Diarrhoea in ‘Urban’ Slums of Dhaka and Adjacent Rural Areas: a Household‐level Analysis
Authors: Khan MMH , Zanuzdana Arina , Burkart Katrin , Krämer Alexander
Published: April 2013

Diarrhoeal diseases constitute an important public health problem in many developing countries including Bangladesh. This study aimed to report the household‐level determinants of diarrhoea using the baseline information of cohort studies conducted in 2008 and 2009. The variation of diarrhoea by 3‐month period was also reported. A total of 3,207 households were systematically selected from 12 slums in Dhaka and three rural villages located nearby. The highest prevalence of diarrhoea was found during the period of September to November (22.7%) and the lowest during December to February (9.2%). Slum households were more affected by diarrhoea as compared with the rural households (OR = 1.49; 95% CI = 1.06–2.08; p = 0.020). Other determinants namely provisional house, sharing water source, and sanitary, and use of surface water were also associated with a higher risk of diarrhoea. In conclusion, slum households suffered more from diarrhoea than rural populations. Moreover, the higher burden of diarrhoea were found to be strongly and persistently associated with adverse housing and environmental conditions. Public health strategies based on our findings are required to reduce the burden of diarrhoea in the study population. Particularly multilevel interdisciplinary actions are needed to improving the quality of housing, water, and sanitation facilities in urban slums of Dhaka, and similar settings elsewhere. Copyright © 2013 John Wiley & Sons, Ltd.
High‐pressure studies of topological insulators Bi2Se3, Bi2Te3, and Sb2Te3
Authors: Manjón F. J. , Vilaplana R. , Gomis O. , Pérez‐González E. , Santamaría‐Pérez D. , Marín‐Borrás V. , Segura A. , González J. , Rodríguez‐Hernández P. , Muñoz A. , Drasar C. , Kucek V. , Muñoz‐Sanjosé V.
Published: April 2013

Bi2Se3, Bi2Te3, and Sb2Te3 are narrow bandgap semiconductors with tetradymite crystal structure (R‐3m) which have been extensively studied along with their alloys due to their promising operation as thermoelectric materials in the temperature range between 300 and 500 K. Studies on these layered semiconductors have increased tremendously in the last years since they have been recently predicted and demonstrated to behave as 3D topological insulators. In particular, a number of high‐pressure studies have been done in the recent years in these materials. In this work we summarize the main results of the high‐pressure studies performed in this family of semiconductors to date. In particular, we review recent results that address the main characteristics of the pressure‐induced electronic topological transition and structural phase transitions observed in this family of compounds. Future high‐pressure studies to be performed on these 3D topological insulators are also commented.
Comparison of various types of coherence and emergent coherent systems
Authors: Squire Richard H. , March Norman H. , Minnick Rebecca A. , Turschmann Richard
Published: April 2013

Coherence is a collective property that is present in Bose–Einstein condensates (BEC), an example of which when charged is superconductivity (SC). Coherence is also believed to be present to a degree in highly efficient energy transfer in certain biological systems. Attributes of coherent systems are examined in BEC, superfluidity and Bardeen, Cooper, and Schrieffer SC and a laser in part 1. Part 2 consists of examination of various proposals for coherence including “emergent coherent systems” where there may be coherence but no phase transition. We discuss “cold” atomic gases, the Casimir effect, an extended version of Förster's resonance energy transfer, Fröhlich's model, exciton‐coupled quantum wells, and conceptually “old” polaritons rejuvenated by new developments. A discussion about highly efficient energy transfer in photosynthesis along with our proposal for a possible new model for this system is the last of the examples. We finish with a discussion about emergent coherent systems and attempt to classify the examples of parts 1 and 2. © 2013 Wiley Periodicals, Inc.
Content‐boosted matrix factorization techniques for recommender systems
Authors: Nguyen Jennifer , Zhu Mu
Published: April 2013

Many businesses are using recommender systems for marketing outreach. Recommendation algorithms can be either based on content or driven by collaborative filtering. We study different ways to incorporate content information directly into the matrix factorization approach of collaborative filtering. These content‐boosted matrix factorization algorithms not only improve recommendation accuracy, but also provide useful insights about the contents, as well as make recommendations more easily interpretable. © 2013 Wiley Periodicals, Inc. Statistical Analysis and Data Mining, 2013
A Thermodynamic Model for Representation Reaction Abilities of Structural Units in Full Composition Range of Fe–Si Binary Melts Based on the Atom–Molecule Coexistence Theory
Authors: Yang Xue‐min , Zhang Meng , Li Peng‐cheng , Li Jin‐yan , Zhang Jian
Published: April 2013

A thermodynamic model for calculating the mass action concentrations of structural units in Fe–Si binary melts based on the atom–molecule coexistence theory, i.e., the AMCT–Ni model, has been developed and verified through comparing with the reported activities of both Si and Fe in the full composition range of Fe–Si binary melts at temperatures of 1693, 1773, 1873, and 1973 K from the literature. The calculated mass action concentration NSi of free Si or NFe of free Fe in the full composition range of Fe–Si binary melts has a good 1:1 corresponding relationship with the reported activity aR,Si of Si or aR,Fe of Fe relative to pure liquid Si(l) or Fe(l) as standard state. The calculated mass action concentration NSi of free Si has a good corresponding relationship with the calculated activity a%,Si of Si referred to 1 mass% of Si as standard state as well as the calculated activity aH,Si of Si relative to the hypothetical pure liquid Si(l) as standard state. The calculated activity a%,Si or aH,Si of Si is much greater than the calculated mass action concentration NSi of free Si in Fe–Si binary melts. The reaction abilities of both Si and Fe show a competitive or coupling relationship in Fe–Si binary melts at the above‐mentioned four temperatures. The calculated mass action concentrations Ni of six structural units as Fe, Si, Fe2Si, Fe5Si3, FeSi, and FeSi2 cannot show the linear relationship with the calculated equilibrium mole numbers ni in 100‐g Fe–Si binary melts simultaneously. A spindle‐type relationship between the calculated mass action concentration Ni and the calculated equilibrium mole number ni of FeSi and FeSi2 in Fe–Si binary melts has been found.
Advanced Solute Conservation Equations for Dendritic Solidification Processes Part II: Numerical Simulations and Comparisons
Authors: El‐Bealy Mostafa Omar
Published: April 2013

The mathematical model of derived solute equations in part I for equiaxed dendritic solidification with melt convection streams and interdendritic thermo‐metallurgical strain is applied numerically to predict macrosegregation distributions with different diffusing mechanisms in dendritic solid. Numerical and experimental results are present for solidification of a Al–4.5% Cu alloy inside horizontal rectangular cavity at different superheats. The numerical simulations were performed by using simpler method developed by Patanker. The experiments were conducted to measure the cooling curves via thermocouples and the metallurgical examinations to measure the grain size and macrosegregation distributions in Part I. Preliminary validity of the model is demonstrated by the qualitative and quantitative agreements between the measurements and predications of cooling curves and predicted macrosegregation distributions including mushy permeability and interdendritic strain. In addition, several important features of macrosegregation in equiaxed dendritic solidification are identified through this combined experimental and numerical study. Also, quantitative agreements between the numerical simulations and experiments reveal several areas for future research work. The differences and errors between predicted macrosegregation results under different diffusing mechanisms have been discussed.
Dry Granulation of Molten Slag using a Rotating Multi‐Nozzle Cup Atomizer and Characterization of Slag Particles
Authors: Qin Yuelin , Lv Xuewei , Bai Chenguang , Chen Pan , Qiu Guibao
Published: April 2013

Blast furnace slag is the main byproduct in the ironmaking process, which contains large amounts of sensible heat. In addition, it's the major raw material for cement. However, the sensible heat is wasted not only without any recovery in the traditional water granulation process at this present. The main challenge is to granulate the slag at a high cooling rate while the heat is also being recovered. This paper describes the hot experiments where a rotating multi‐nozzle cup atomizer (RMCA) is used to atomize the molten blast furnace slag without water impingement. The atomization process shows good agreement with Rayleigh's mechanism. The particle size of the slag particle is strongly controlled by the rotating speed and the nozzle diameter, and the higher rotating speed and smaller nozzle diameter are beneficial for obtaining smaller and more uniform slag particles. Moreover, the slag particle still has a high content of glass, which is suitable for cement manufacture.
Untersuchung von Zug‐Druck‐Kalottenlagern im Großversuch
Authors: Mang F. , Herion St. , Fleischer O. , Koch E.
Published: April 2013

Dieser Beitrag beschreibt die versuchstechnischen Untersuchungen von zug‐ und druckbelasteten Brückenlagern, die im Auftrag der Deutschen Bahn AG an der Versuchsanstalt für Stahl, Holz und Steine der Universität Karlsruhe (TH) durchgeführt wurden, und stellt die daraus gewonnenen Ergebnisse dar. Dabei handelte es sich um eine Prüfung der Funktionalität der Lager und Untersuchungen zum Langzeitverhalten von Zug‐Druck‐Kalottenlagern, wie sie beim Bauprojekt "Lehrter Bahnhof Berlin" eingesetzt werden. Die Großversuche erfolgten an zwei Original‐Lagern im Maßstab 1:1 unter realistischen Auflagerlasten. Darüber hinaus werden Ermüdungsversuche an vorgespannten HV‐Schrauben M 36 der Festigkeitsklasse 10.9 beschrieben und die Ergebnisse dieser Versuche diskutiert. Diese Schrauben werden ebenfalls in den zuvor erwähnten Lagern eingesetzt.
Bruchmechanische Methoden im Sicherheitssystem des Stahlbaus
Authors: Sedlacek G. , Höhler S. , Kuhn B. , Langenberg P.
Published: April 2013

Bruchmechanische Methoden haben im Stahlbau Fuß gefaßt, um die Sicherheit von Tragwerken nicht nur hinsichtlich ihrer Festigkeit, sondern auch hinsichtlich ihrer Zähigkeit nachweisen zu können. Zähigkeitsnachweise sind erforderlich, wenn ausreichende Sicherheit gegenüber Sprödbruch erzielt werden muß. Für standardisierte Fälle führt der Zähigkeitsnachweis zu einfachen Verfahren der Stahlgütewahl, z.B. nach Teil 1.10 der EN 1993 oder nach EN 13445. Diesem Zähigkeitsnachweis liegen Werkzeuge der Bruchmechanik zugrunde, die nicht nur im konstruktiven Stahlbau, sondern auch im Behälterbau im Rahmen der Europäischen Vereinheitlichung der technischen Regelwerke harmonisiert sind. Die neuen Methoden der Stahlgütewahl führen nicht nur zu sicheren Entscheidungen für die Wahl von Werkstoff und Bauteilgestaltung, sie erhöhen gegenüber den früheren empirischen Verfahren auch die Wirtschaftlichkeit durch die Verwendbarkeit größerer Blechdicken und höherer Stahlfestigkeiten. Die Methoden der Stahlgütewahl gelten bislang für das Temperaturübergangsverhalten der Zähigkeit, jedoch noch nicht für das Hochlageverhalten. Hochlagennachweise sind aber besonders dort, wo Tragfähigkeitsnachweise mit der Annahme der Bildung plastischer Zonen geführt werden, z.B. bei Erdbebenbeanspruchung und in Fällen von Sondereinwirkungen wie Anprall und Explosion, von großer Bedeutung. Hier gibt es in Deutschland bislang nur ein empirisches Prüfverfahren, den Aufschweißbiegeversuch.
Modellierungsvarianten und Empfehlungen bei der Ermittlung von Struktur‐ und Kerbspannungen auf Basis Finiter Element‐Berechnungen
Authors: Feldmann Markus , Eichler Björn , Boos Bernd , Henkel Joachim , Mack Benjamin
Published: April 2013

Bei Einsatz von hochfesten Baustählen im Kran‐ und Brückenbau gewinnen Betriebsfestigkeitsuntersuchungen zunehmend an Bedeutung. Während beispielsweise im Offshore‐Sektor die Beurteilung des Ermüdungsverhaltens von Bauteilen mittels numerischer Methoden etabliert ist, werden Finite‐Element‐Berechnungen zur Bestimmung von Struktur‐ bzw. Kerbspannungen im Bauwesen oder auch im Kranbau seltener herangezogen. Hier dominierten bisher Nennspannungskonzepte mit einer Vielzahl an Kerbdetails. Mittlerweile weisen jedoch bereits gängige Computersysteme Leistungsressourcen auf, mit denen auch komplexeste Geometrien mit angemessenem Rechenaufwand simuliert werden können. Anhand zweier einfacher Beispiele (Stumpfstoß, Längssteife) werden wesentliche Anforderungen an das FE‐Modell und die maßgeblichen Modellierungsparameter unter Berücksichtigung von IIW‐Empfehlungen aufgezeigt. Insbesondere wird dabei auf die Vernetzung und die Elementanforderungen eingegangen. Für geschweißte Stumpfstoßverbindungen wurden darüber hinaus aus umfangreichen Parameteruntersuchungen Näherungsformeln zur Berechnung von Kerbformzahlen abgeleitet.

Modeling variations and recommendations for the evaluation of structural and notch stresses based on finite element simulations. Structural durability analyses become increasingly important when using high strength structural steels in crane‐ and bridge construction. While the numerical based assessment of the fatigue behavior is established in the offshore‐sector, finite element computations for the derivation of structural and notch stresses are rarely used in civil engineering and in crane construction. Nominal stress concepts with a variety of notch details are dominating here until now. However, in the meantime common computer systems exhibit acceptable capabilities that allow for the simulation of the most complex geometries with reasonable efforts. Two simple examples (butt joint, longitudinal attachment) will demonstrate the essential requirements of the FE‐model and the relevant model parameters by taking the IIW‐recommendations in consideration. In particular, meshing details and element specifications are addressed. Furthermore, approximation formulas derived from parametric studies have been developed for the estimation of notch stress concentration factors for welded butt joints.
Beanspruchungskollektive von Turmdrehkranen
Authors: Eiwan Christoph , Fischl Andreas , Bucak Ömer , Seeßelberg Christoph
Published: April 2013

Um im internationalen Wettbewerb konkurrenzfähig zu bleiben, müssen Hersteller bereits bei der Bemessung von Turmdrehkranen innovativ arbeiten. Die Bemessung von Turmdrehkranen erfolgt dabei auf dem schmalen Grat zwischen Wirtschaftlichkeit und Sicherheit. Für den Betriebsfestigkeitsnachweis wie auch den statischen Festigkeitsnachweis von Turmdrehkranen ist es daher wichtig, genaue Kenntnisse der Einsatzbedingungen und des Betriebsverhaltens der Krane zu erhalten.

Load spectras of tower cranes. To remain competitive in international competition, manufacturers already have to work innovatively when designing tower cranes. The design of tower cranes is carried out on the thin line between profitability and safety. For the fatigue design, as well as the static strength analysis of tower cranes, it is important to obtain accurate knowledge of the working conditions and the operational performance of the cranes.
Schweißen auf der Baustelle
Authors: Trommer Gerd
Published: April 2013

Schweißer und ihre Tätigkeit auf Baustellen stellen spezifische Anforderungen an ihr Werkzeug. Moderne, dem aktuellen Stand der Technik entsprechende Stromquellen erfüllen sie umfassend. Beispielhaft dafür steht ein Elektroden‐ und WIG‐DC‐Schweißsystem der 150‐A‐Klasse. Seine Leistungsmerkmale und sein Anwendungsspektrum bilden eine gelungene Verbindung aus Technik, Qualität, Wirtschaftlichkeit und Bedienerfreundlichkeit.
D3-instantons, mock theta series and twistors
Authors: Alexandrov Sergei , Manschot Jan , Pioline Boris
Published: April 2013

Abstract

The D-instanton corrected hypermultiplet moduli space of type II string theory compactified on a Calabi-Yau threefold is known in the type IIA picture to be determined in terms of the generalized Donaldson-Thomas invariants, through a twistorial construction. At the same time, in the mirror type IIB picture, and in the limit where only D3-D1-D(-1)-instanton corrections are retained, it should carry an isometric action of the S-duality group SL(2,
$ \mathbb{Z} $
). We prove that this is the case in the one-instanton approximation, by constructing a holomorphic action of SL(2,
$ \mathbb{Z} $
) on the linearized twistor space. Using the modular invariance of the D4-D2-D0 black hole partition function, we show that the standard Darboux coordinates in twistor space have modular anomalies controlled by period integrals of a Siegel-Narain theta series, which can be canceled by a contact transformation generated by a holomorphic mock theta series.
“Anatomy Lesson of Frederik Ruysch” of 1670: A Tribute to Ruysch’s Contributions to Lymphatic Anatomy
Authors: IJpma Frank F. A. , van Gulik Thomas M.
Published: April 2013

Background

Frederick Ruysch was one of the most prominent Dutch physicians of the seventeenth and eighteenth centuries. For more than 65 years, he was the Praelector Anatomiae (Lecturer of Anatomy) of the Amsterdam Guild of Surgeons. During his career, he conducted many dissections at the guild’s theatre to teach anatomy. Ruysch was internationally renowned for his great dissection skills and his innovative techniques for preserving anatomical specimens. The “Anatomy Lesson of Dr. Frederik Ruysch” painted in 1670, is thought to be a group portrait undertaken to commemorate the officials of the Guild of Surgeons. Ruysch was portrayed performing an anatomical dissection of inguinal lymph nodes on the corpse of an executed criminal. This portrait is one of the earliest paintings focusing on the “lymphatic system.”

Methods

We investigated the medical background of the painting by revisiting Ruysch’s original work from the mid‐seventeenth century. His contributions to the early history of “lymphatic anatomy” are assessed and interpreted from the perspective of the renewed interest in “lymphatic imaging” today.

Results and conclusions

Frederik Ruysch should be considered one of the pioneers contributing to the early knowledge of the lymphatic system. He succeeded in dissecting the lymphatic vessels and valves with the aid of his innovative dissection and preservation techniques. The famous group portrait of the Amsterdam Guild of Surgeons with Ruysch demonstrating the lymph nodes pays tribute to his work on which we still rely today.
Extended Lymphadenectomy in Esophageal Cancer is Debatable
Authors: Herbella Fernando A. M. , Laurino Neto Rafael M. , Allaix Marco E. , Patti Marco G.
Published: April 2013

Surgery is an essential part of the treatment of patients with esophageal carcinoma. However, there is no consensus on whether the surgical technique can be improved to promote better survival outcome. Specifically, the real value of the addition of a radical lymphadenectomy to the esophageal resection is still elusive and controversial. This paper focuses on the debate of esophagectomy and lymphadenectomy for the treatment of esophageal cancer.
Stability and sensitivity analysis in a simplified solid rocket motor flow
Authors: Boyer G. , Casalis G. , Estivalèzes J. L.
Published: April 2013

The present article aims at enhancing the computation of the global stability modes of the internal flow of solid rocket motors (SRMs) approximated by the Taylor–Culick solution. This modal approach suffers from the consequences of the non-normality of the global linearized incompressible Navier–Stokes operator, namely the lack of robustness of the eigenvalues that can lead to the computation of pseudo-modes rather than actual eigenmodes. In this respect, the effects of non-normality associated with strongly amplified eigenfunctions are highlighted on a simplified convective–diffusive stability problem with uniformly accelerated base state, the latter property being a typical characteristic of the Taylor–Culick flow. Non-convergence zones for the eigenvalues are exhibited for large Reynolds numbers and are related to the critical sensitivity to disturbances applied to one of the boundary conditions. For this reason, and according to experimental and numerical data related to the stability of simplified SRMs, a global stability analysis is performed assuming that the hydrodynamic fluctuations emerge from a geometrical defect applied at the sidewall. This comes to fix the upstream boundary condition at the abscissa of the sidewall disturbance. The resulting eigenmodes are shown to be discrete, numerically converged, well identified by a finite number of points of undefined phase of the velocity fluctuations. They marginally depend on Reynolds number variations, but are modified by changes on the boundaries location. As in the simplified problem, the inflow boundary condition is the most critical in terms of sensitivity to numerical errors, although not dramatic. Finally, the sensitivity analysis to infinitesimal base flow changes indicates that the variations applied close to the inflow boundary condition induce the largest move of the eigenvalues. In spite of the large non-normal effects induced by the large polynomial growth of the eigenfunctions, this paper shows that discrete instabilities may emerge from a wall defect, in contrast to configurations without such a geometrical perturbation whose dynamics may be rather driven by pseudo-modes.
The Bulge of M31
Authors: Mould Jeremy
Published: April 2013

Bulges are not just elliptical subgalaxies situated in the centers of large spirals, though it might seem so from their ages and chemistry. In fact, bulge kinematics have been known to be different since the first long slit spectra were obtained. M31 presents the best opportunity to investigate all the issues of the stellar populations of bulges. This review collects the array of probing data that has been accumulated during the last decade. But the intriguing question ‘how did it form like this?’ remains.
Primary mastoid cyst
Authors: Tan C Y , Chong S , Shaw C-K L
Published: April 2013

Objective:

To report an unusual case of a primary mastoid cyst (congenital or developmental) in a patient without otological symptoms.

Method:

Case report and review of the English language literature.

Results:

Primary mastoid cyst is a newly reported and very rare pathological entity. Mastoid cysts usually occur secondary to chronic infection, inflammation or trauma. Review of the medical literature highlights the rarity of this condition.

Conclusion:

This report describes the experience gained by the diagnosis and management of this patient. It emphasises the importance of clinical vigilance so that proper treatment may be instituted in a timely manner.
The Politicization of Women Workers at War: Labour in Chongqing's cotton mills during the Anti-Japanese War
Authors: HOWARD JOSHUA H.
Published: April 2013

Building on recent scholarship that highlights social change caused by the Anti-Japanese War, this paper traces the politicization of women working in the cotton mills of Chongqing, the Nationalist wartime capital. Upon joining the workforce in the late 1930s, most cotton mill hands were young, uneducated women expected to endure hard work and remain physically confined to the factories. By 1945, women workers were at the forefront of a militant labour movement, writing manifestoes and petitioning government officials. This process of politicization stemmed from their decision to work in factories, which breached societal norms, and their experience of disciplined labour regimes and brutal working conditions, which fostered an incipient class-consciousness. Moreover, Nationalist-sponsored factory education campaigns had the unintended effect of leading women to challenge class exploitation and sexual discrimination. Their participation in the labour movement, which was fuelled by their struggle for economic justice and desire for higher social status, used both legal forms— especially petitions and letters to the press couched in the wartime nationalist rhetoric of shared sacrifice—and extralegal means, namely class violence. The paper concludes that the social changes and conflict that accompanied women's wartime work helped prepare the terrain for Communist rule.
Identification of compounds from Paris polyphylla (ChongLou) active against Dactylogyrus intermedius
Authors: LI ZE-HONG , WAN JIA-YU , WANG GUI-QIN , ZHAO FU-GUANG , WEN JI-HONG
Published: April 2013

The present study was designated to ascertain the anthelmintic activity of the rhizomes of Paris polyphylla and to isolate and characterize the active constituents. The methanol extract from rhizomes of P. polyphylla showed signiﬁcant anthelmintic activity against Dactylogyrus intermedius with the median effective concentration (EC50) 22·5 mg L−1. Based on this finding, the methanol extract was fractionated by silica gel column chromatography in a bioassay-guided fractionation yielding 2 bioactive compounds, the structures of these compounds were elucidated as formosanin C and polyphyllin VII. The in vivo tests revealed that formosanin C and polyphyllin VII were significantly effective against D. intermedius with EC50 values of 0·6 and 1·2 mg L−1, respectively. The acute toxicities (LC50) of formosanin C and polyphyllin VII for grass carp were 2·8 and 2·9 mg L−1, respectively. The overall results provide important information for the potential application of formosanin C and polyphyllin VII in the therapy of serious infection caused by D. intermedius.
Genetic dissection of drug resistance in trypanosomes
Authors: ALSFORD SAM , KELLY JOHN M. , BAKER NICOLA , HORN DAVID
Published: April 2013

The trypanosomes cause two neglected tropical diseases, Chagas disease in the Americas and African trypanosomiasis in sub-Saharan Africa. Over recent years a raft of molecular tools have been developed enabling the genetic dissection of many aspects of trypanosome biology, including the mechanisms underlying resistance to some of the current clinical and veterinary drugs. This has led to the identification and characterization of key resistance determinants, including transporters for the anti-Trypanosoma bruceidrugs, melarsoprol, pentamidine and eflornithine, and the activator of nifurtimox-benznidazole, the anti-Trypanosoma cruzidrugs. More recently, advances in sequencing technology, combined with the development of RNA interference libraries in the clinically relevant bloodstream form ofT. bruceihave led to an exponential increase in the number of proteins known to interact either directly or indirectly with the anti-trypanosomal drugs. In this review, we discuss these findings and the technological developments that are set to further revolutionise our understanding of drug-trypanosome interactions. The new knowledge gained should inform the development of novel interventions against the devastating diseases caused by these parasites.
Comparison of psychotherapies for adult depression to pill placebo control groups: a meta-analysis
Authors: Cuijpers P. , Turner E. H. , Mohr D. C. , Hofmann S. G. , Andersson G. , Berking M. , Coyne J.
Published: April 2013

Background

The effects of antidepressants for treating depressive disorders have been overestimated because of selective publication of positive trials. Reanalyses that include unpublished trials have yielded reduced effect sizes. This in turn has led to claims that antidepressants have clinically insignificant advantages over placebo and that psychotherapy is therefore a better alternative. To test this, we conducted a meta-analysis of studies comparing psychotherapy with pill placebo.

Method

Ten 10 studies comparing psychotherapies with pill placebo were identified. In total, 1240 patients were included in these studies. For each study, Hedges’ g was calculated. Characteristics of the studies were extracted for subgroup and meta-regression analyses.

Results

The effect of psychotherapy compared to pill placebo at post-test was g = 0.25 [95% confidence interval (CI) 0.14–0.36, I2 = 0%, 95% CI 0–58]. This effect size corresponds to a number needed to treat (NNT) of 7.14 (95% CI 5.00–12.82). The psychotherapy conditions scored 2.66 points lower on the Hamilton Depression Rating Scale (HAMD) than the placebo conditions, and 3.20 points lower on the Beck Depression Inventory (BDI). Some indications for publication bias were found (two missing studies). We found no significant differences between subgroups of the studies and in meta-regression analyses we found no significant association between baseline severity and effect size.

Conclusions

Although there are differences between the role of placebo in psychotherapy and pharmacotherapy research, psychotherapy has an effect size that is comparable to that of antidepressant medications. Whether these effects should be deemed clinically relevant remains open to debate.