bluuebunny/crossref_metadata_2025_split huggingface dataset:
Grünbrücken als Verbundkonstruktion
Authors: Suffner Andrea , Ommert Christian , Schiller Guido 
Published: February 2013

AbstractFür die Bauaufgabe Grünbrücke sind verschiedene Bauwerkskonstruktionen bekannt und in der Vergangenheit ausgeführt worden. Unter den besonderen Bedingungen einer ebenen Topografie und der Errichtung der Bauwerke unter Aufrechterhaltung des Verkehrs über bestehenden Autobahnen mit hoher Verkehrsbelastung wird eine mittelstützenfreie Verbundkonstruktion beschrieben sowie auf die Besonderheiten in Planung und Herstellung eingegangen.Im Land Brandenburg wurden in den letzten drei Jahren drei dieser Grünbrücken gleicher Bauart mit Verbundfertigteilen errichtet.Green bridges as composite structuresSeveral types of structures are known to build green bridges and have been implemented in the past. Under the particular conditions of an even topography – even or flat terrain – and of construction whilst maintaining traffic above existing highly frequented motorways, a composite structure without central supports is described and the particularities of its design and construction are explained.In the State of Brandenburg, in the last three years, three of these green bridges of the same construction type were erected with prefabricated composite elements.
Experimentelle Untersuchungen zur mitwirkenden Breite für Querkraft von einfeldrigen Fahrbahnplatten
Authors: Reißen Karin , Hegger Josef 
Published: February 2013

AbstractDie Anforderungen an Brückenbauwerke haben sich in den vergangenen Jahren infolge der steigenden Verkehrszahlen deutlich erhöht. Gleichzeitig hat sich mit der Umstellung der Normen der rechnerische Querkraftwiderstand von Bauteilen ohne Querkraftbewehrung verringert. Als Folge lässt sich für Brückenbauwerke im Bestand mit Fahrbahnplatten ohne Querkraftbewehrung nach derzeitigen technischen Regeln oft keine ausreichende Querkrafttragfähigkeit nachweisen. Daher wurde im Rahmen eines von der Bundesanstalt für Straßenwesen (BASt) geförderten Forschungsvorhabens das Querkrafttragverhalten von Fahrbahnplatten aus Stahlbeton genauer analysiert. Der vorliegende Aufsatz beschreibt die Ergebnisse der experimentellen Untersuchungen zur maßgebenden Lastverteilungsbreite für Radlasten bei einfeldrigen, gelenkig gelagerten Platten ohne Querkraftbewehrung.Experimental investigations on the effective width for shear of single span bridge deck slabsThe requirements for the load‐carrying capacity of bridges have increased significantly due to rising traffic loads in the last decades. Furthermore, the design rules of the German codes have changed leading to smaller calculated shear capacities of reinforced concrete members without shear reinforcement. Therefore, the calculated shear capacity of a large number of existing concrete bridge deck slabs without shear reinforcement is not sufficient. For the above reasons, the shear‐bearing behaviour of slabs has been investigated within a research programme funded by the Federal Highway Research Institute of Germany (BASt). The paper presents the results of the experimental investigations on the effective width for shear of simply supported single span slabs without shear reinforcement.
Beurteilung der Wirkungsweise von adaptiven Seildämpfern im Brückenbau durch Koppelung von numerischer Simulation und Experiment
Authors: Scheufler Wolfgang , Burghard Stefan , Fischer Oliver , Braun Christian 
Published: February 2013

AbstractIn vielen weit gespannten Schrägseilbrücken werden Seildämpfer zur Verringerung von Seilschwingungen eingebaut. Bedämpft werden dabei in erster Linie unerwünschte Querschwingungen (Schwingungen außerhalb der Kabelebene) der Tragseile. Neben der vorgesehenen Reduzierung der Bewegungen in der Kabelebene der Wirkungsrichtung der Dämpfer zeigen Untersuchungen, dass auch die Bewegungen quer zu dieser Richtung von den Dämpfern beeinflusst werden. Mithilfe der hybriden Versuchstechnik sollen diese Phänomene im Rahmen eines Forschungsvorhabens am Lehrstuhl für Massivbau der Technischen Universität München genauer untersucht werden.Evaluation of the effects of adaptive cable dampers by use of hybrid testing methodsVarious wide spanned cable‐stayed bridges are protected against cable vibrations with vibration absorbers. The focus of the damping measures is to reduce lateral oscillations of the cables. Although reducing vibrations in the effective direction of the installed vibration absorber, it is approved by research that vibrations are influenced transverse to the vibration absorber's effective direction as well. Using hybrid testing methods these phenomenons shall be discovered in detail within an actual research project at the Department of Concrete Structures of the Technische Universität München.
A modified metabolic model for mixed culture fermentation with energy conserving electron bifurcation reaction and metabolite transport energy
Authors: Zhang Fang , Zhang Yan , Chen Man , van Loosdrecht Mark C.M. , Zeng Raymond J. 
Published: February 2013

AbstractA modified metabolic model for mixed culture fermentation (MCF) is proposed with the consideration of an energy conserving electron bifurcation reaction and the transport energy of metabolites. The production of H2 related to NADH/NAD+ and Fdred/Fdox is proposed to be divided in three processes in view of energy conserving electron bifurcation reaction. This assumption could fine‐tune the intracellular redox balance and regulate the distribution of metabolites. With respect to metabolite transport energy, the proton motive force is considered to be constant, while the transport rate coefficient is proposed to be proportional to the octanol–water partition coefficient. The modeling results for a glucose fermentation in a continuous stirred tank reactor show that the metabolite distribution is consistent with the literature: (1) acetate, butyrate, and ethanol are main products at acidic pH, while the production shifts to acetate and propionate at neutral and alkali pH; (2) the main products acetate, ethanol, and butyrate shift to ethanol at higher glucose concentration; (3) the changes for acetate and butyrate are following an increasing hydrogen partial pressure. The findings demonstrate that our modified model is more realistic than previous proposed model concepts. It also indicates that inclusion of an energy conserving electron bifurcation reaction and metabolite transport energy for MCF is sound in the viewpoint of biochemistry and physiology. Biotechnol. Bioeng. 2013; 110: 1884–1894. © 2013 Wiley Periodicals, Inc.
Der Gelbereich im Phasendiagramm von Klebstoffen
Authors: Simon Gerhard 
Published: February 2013

AbstractBeim Hallenzusammenbruch in Bad Reichenhall im Jahr 2006, der bei Kälte unter Schneelast erfolgte, waren 15 Tote zu beklagen. Der Hallendachzusammenbruch des Supermarktes in Falkensee im Sommer 2009 erfolgte glücklicherweise erst nach Ladenschluss. Beide Hallen enthielten Brettschichtholzbinder, das sind aus Holzlatten zusammengeklebte Balken. Die beiden Vorkommnisse fordern die Klärung der Frage, ob ausgehärtete Klebefugen zu den Festkörpern zählen und wie solche zu berechnen sind; oder sind sie wie zähe Flüssigkeiten zu behandeln oder gar wie Gele?
Survey of integrated‐circuit‐oscillator phase‐noise analysis
Authors: Pankratz Erik , Sánchez‐Sinencio Edgar 
Published: February 2013

ABSTRACTThis tutorial distills the salient phase‐noise analysis concepts and key equations developed over the last 75 years relevant to integrated circuit oscillators. Oscillator phase and amplitude fluctuations have been studied since at least 1938 when Berstein solved the Fokker–Planck equations for the phase/amplitude distributions of a resonant oscillator.The principal contribution of this work is the organized, unified presentation of eclectic phase‐noise analysis techniques, facilitating their application to integrated circuit oscillator design. Furthermore, we demonstrate that all these methods boil down to obtaining three things: (1) noise modulation function; (2) noise transfer function; and (3) current‐controlled oscillator gain. For each method, this paper provides a short background explanation of the technique, a step‐by‐step procedure of how to apply the method to hand calculation/computer simulation, and a worked example to demonstrate how to analyze a practical oscillator circuit with that method.This survey article chiefly deals with phase‐noise analysis methods, so to restrict its scope, we limit our discussion to the following: (1) analyzing integrated circuit metal–oxide–semiconductor/bipolar junction transistor‐based LC, delay, and ring oscillator topologies; (2) considering a few oscillator harmonics in our analysis; (3) analyzing thermal/flicker intrinsic device‐noise sources rather than environmental/parametric noise/wander; (4) providing mainly qualitative amplitude‐noise discussions; and (5) omitting measurement methods/phase‐noise reduction techniques. Copyright © 2013 John Wiley & Sons, Ltd.
Upper atmosphere response to stratosphere sudden warming: Local time and height dependence simulated by GAIA model
Authors: Liu Huixin , Jin Hidekatsu , Miyoshi Yasunobu , Fujiwara Hitoshi , Shinagawa Hiroyuki 
Published: February 2013

AbstractThe whole atmosphere model GAIA is employed to shed light on atmospheric response to the 2009 major stratosphere sudden warming (SSW) from the ground to exobase. Distinct features are revealed about SSW impacts on thermospheric temperature and density above 100 km altitude. (1) The effect is primarily quasi‐semidiurnal in tropical regions, with warming in the noon and pre‐midnight sectors and cooling in the dawn and dusk sectors. (2) This pattern exists at all altitudes above 100 km, with its phase being almost constant above 200 km, but propagates downward in the lower thermosphere between 100 and 200 km. (3) The northern polar region experiences warming in a narrow layer between 100 and 130 km, while the southern polar region experiences cooling throughout 100–400 km altitudes. (4) The global net thermal effect on the atmosphere above 100 km is a cooling of approximately −12 K. These characteristics provide us with an urgently needed global context to better connect and understand the increasing upper atmosphere observations during SSW events.
Stream temperature response to variable glacier coverage in coastal watersheds of Southeast Alaska
Authors: Fellman Jason B. , Nagorski Sonia , Pyare Sanjay , Vermilyea Andrew W. , Scott Durelle , Hood Eran 
Published: February 2013

AbstractWe measured stream temperature continuously during the 2011 summer run‐off season (May through October) in nine watersheds of Southeast Alaska that provide spawning habitat for Pacific salmon. The nine watersheds have glacier coverage ranging from 0% to 63%. Our goal was to determine how air temperature and watershed land cover, particularly glacier coverage, influence stream temperature across the seasonal glacial meltwater hydrograph. Multiple linear regression models identified mean watershed elevation (related to glacier extent) and watershed lake coverage (%) as the strongest landscape controls on mean monthly stream temperature, with the weakest (May) and strongest (July) models explaining 86% and 97% of the temperature variability, respectively. Mean weekly stream temperature was significantly correlated with mean weekly air temperature in seven streams; however, the relationships were weak to non‐significant in the streams influenced by glacial run‐off. Streams with >30% glacier coverage showed decreasing stream temperatures with rising summer air temperatures, whereas those with <30% glacier coverage exhibited summertime warming. Glaciers also had a cooling effect on monthly mean stream temperature during the summer (July through September) equivalent to a decrease of 1.1 °C for each 10% increase in glacier coverage. The maximum weekly average temperature (an index of thermal suitability for salmon) in the six glacial streams was substantially below the lower threshold for optimum salmon growth. This finding suggests that although glaciers are important for moderating summer stream temperatures, future reductions in glacier run‐off may actually improve the thermal suitability of some glacially dominated streams in Southeast Alaska for salmon. Copyright © 2013 John Wiley & Sons, Ltd.
On quantifying hydraulic conductance at the soil–root interface
Authors: Li Yan , Pan Li‐Ping , Xu Gui‐Qing 
Published: February 2013

AbstractThis study sought to test a widely used hypothesis in water transport from soil to root: the soil textural effect on soil–root interfacial conductance can be quantified by the degree of soil water saturation. This hypothesis is inferred from basic soil physics and is commonly used in modelling root water uptake. However, it has never been subjected to rigorous experimental test. In the current study, the soil texture effect on the interfacial hydraulic conductance was evaluated on well‐watered pot‐grown cotton plants, with soil particle size ranges of 0–0.05, 0.05–0.1, 0.1–0.2, 0.2–0.3, 0.3–0.45, 0.45–0.6 and 0.6–1 mm in seven treatments, in addition to hydroponics. However, our experimental results showed that the volumetric soil water content, not degree of saturation, is the best explanatory variable for quantifying the interfacial effect on hydraulic conductance. Further analysis indicated that if temporal change of this interfacial effect on hydraulic conductance is the subject of concern, degree of saturation may still be a valid option. If soil textural or spatial variation in root water uptake is the subject of concern, volumetric soil water content is best suited to quantifying the interfacial effect on hydraulic conductance. Copyright © 2013 John Wiley & Sons, Ltd.
Crystal structures of nitric oxide reductases provide key insights into functional conversion of respiratory enzymes
Authors: Tosha Takehiko , Shiro Yoshitsugu 
Published: February 2013

AbstractSummary: Respiration is an essential biological process to get bioenergy, ATP, for all kingdoms of life. Cytochrome c oxidase (COX) plays central role in aerobic respiration, catalyzing the reduction of O2 coupled with pumping proton across the biological membrane. Nitric oxide reductase (NOR) involved in anaerobic nitrate respiration is suggested to be evolutionary related to COX and share the same progenitor with COX, on the basis of the amino acid sequence homology. Contrary to COX, NOR catalyzes the reduction of nitric oxide and shows no proton pumping ability. Thus, the respiratory enzyme acquires (or loses) proton pumping ability in addition to the conversion of the catalytic property along with the environmental change on earth. Recently, we solved the structures of two types of NORs, which provides novel insights into the functional conversion of the respiratory enzymes. In this review, we focus on the structural similarities and differences between COXs and NORs and discuss possible mechanism for the functional conversion of these enzymes during molecular evolution. © 2013 IUBMB Life, 65(3):217–226, 2013
Regolith production and transport in the Susquehanna Shale Hills Critical Zone Observatory, Part 1: Insights from U‐series isotopes
Authors: Ma Lin , Chabaux Francois , West Nikki , Kirby Eric , Jin Lixin , Brantley Susan 
Published: February 2013

AbstractTo investigate the timescales of regolith formation on hillslopes with contrasting topographic aspect, we measured U‐series isotopes in regolith profiles from two hillslopes (north facing versus south facing) within the east‐west trending Shale Hills catchment in Pennsylvania. This catchment is developed entirely on the Fe‐rich, Silurian Rose Hill gray shale. Hillslopes exhibit a topographic asymmetry: The north‐facing hillslope has an average slope gradient of ~20°, slightly steeper than the south‐facing hillslope (~15°). The regolith samples display significant U‐series disequilibrium resulting from shale weathering. Based on the U‐series data, the rates of regolith production on the two ridgetops are indistinguishable (40 ± 22 versus 45 ± 12 m/Ma). However, when downslope positions are compared, the regolith profiles on the south‐facing hillslope are characterized by faster regolith production rates (50 ± 15 to 52 ± 15 m/Ma) and shorter durations of chemical weathering (12 ± 3 to 16 ± 5 ka) than those on the north‐facing hillslope (17 ± 14 to 18 ± 13 m/Ma and 39 ± 20 to 43 ± 20 ka). The south‐facing hillslope is also characterized by faster chemical weathering rates inferred from major element chemistry, despite lower extents of chemical depletion. These results are consistent with the influence of aspect on regolith formation at Shale Hills; we hypothesize that aspect affects such variables as temperature, moisture content, and evapotranspiration in the regolith zone, causing faster chemical weathering and regolith formation rates on the south‐facing side of the catchment. The difference in microclimate between these two hillslopes is inferred to have been especially significant during the periglacial period that occurred at Shale Hills at least ~15 ka before present. At that time, the erosion rates may also have been different from those observed today, perhaps denuding the south‐facing hillslope of regolith but not quite stripping the north‐facing hillslope. An analysis of hillslope evolution and response timescales with a linear mass transport model shows that the current landscape at Shale Hills is not in geomorphologic steady state (i.e., so‐called dynamic equilibrium) but rather is likely still responding to the climate shift from the Holocene periglacial to the modern, temperate conditions.
Influence of glycation on microencapsulating properties of soy protein isolate–lactose blends
Authors: Li Xin‐Rong , Tang Chuan‐He 
Published: February 2013

AbstractBackgroundThere is increasing interest in developing encapsulating materials from vegetable proteins as an abundant alternative for animal proteins or petroleum‐derived polymers. Relationships between emulsifying and microencapsulating properties of soy protein isolate or blends with carbohydrates have not been well characterised. The influence of glycation between soy protein isolate and lactose prior to emulsification on the emulsifying and microencapsulation properties of their blends was investigated in this work.ResultsAnalysis of the emulsion characteristics indicated that the glycation resulted in a decreased size of emulsion droplets, enhanced emulsion stability, and decreased apparent viscosity, suggesting improvement of emulsifying properties. In the spray‐dried emulsions, the treatment with increasing degree of glycation from 0 to 13% progressively increased the retention efficiency from 96.4 to 98.3%. The glycation with an appropriate degree of glycation significantly decreased mean droplet size of the reconstituted emulsions, and increased the dissolution rate and capacity. However, the storage stability of the powders at 75% relative humidity was decreased by the glycation, though to a limited extent.ConclusionGlycation improves the encapsulation efficiency, redispersion and dissolution properties of soy protein isolate–lactose blends, but slightly accelerated the storage instability of the spray‐dried emulsions. The improvement of microencapsulation properties has been related to that of the emulsifying properties. © 2013 Society of Chemical Industry
Margin mapping in transoral surgery for head and neck cancer
Authors: Hinni Michael L. , Zarka Matthew A. , Hoxworth Joseph M. 
Published: February 2013

Objectives/HypothesisTo evaluate the results of patients treated by transoral laser microsurgery and margin mapping with attention to deep margin dimensions in the lateral pharyngeal wall.Study DesignA microscopic margin analysis of multiblock surgical specimens applied to a prospectively accrued case series of squamous cell carcinoma of the palatine tonsils.MethodsThere were 128 tonsil cancers analyzed that were removed transorally, using microscopic margin mapping by surgeon and pathologist. The closest deep and peripheral margins were assessed. The results were then related to a study of the normal dimensions of the lateral pharyngeal wall in 20 healthy patients using magnetic resonance imaging. Outcome measures included number of positive margins, narrowest margin, local control, and disease‐free and overall survival.ResultsThe average closest margin was 1.98 mm (range, 0.30–6.50 mm) deep and 2.82 mm (range, 1.00–5.00 mm) peripheral. There was one positive margin encountered in the previously untreated group (1%), and one local recurrence ultimately developed. Radiographic measures revealed a mean minimal thickness of the lateral pharyngeal wall musculature of 2.4 mm. With mean follow‐up of 4.3 years (range, 2–14 years), the 5‐year estimate for local control is 99%, disease‐free survival is 94.5%, and overall survival is 76%.ConclusionsMargin mapping achieves a low rate of positive margins and is associated with good local control. Based on lateral pharyngeal wall anatomy, wide margins are often unobtainable and may be unnecessary so long as the final inked margin is clear.Level of Evidence4.
A Serum‐Resistant Low‐Generation Polyamidoamine with PEI 423 Outer Layer for Gene Delivery Vector
Authors: Pan Shirong , Cao Duanwen , Huang Huan , Yi Wu , Qin Linhao , Feng Min 
Published: February 2013

AbstractA new derivative of polyamidoamine and polyethylenimine, G2.5‐PEI 423 or G1.5‐PEI 423, is prepared by an amidation reaction of PAMAM G2.5 or PAMAM G1.5 using PEI 423. The polycations show a great ability to combine with pDNA to form complexes, which protect the pDNA from nuclease degradation. The polymers display stronger buffer capacity and lower cytotoxicity. The complexes have particle sizes of 120–180 nm and zeta potentials of 20–40 mV. The G2.5‐PEI 423 complexes display much higher transfection efficiencies than PAMAM G5 and Lipo‐2k, and the G1.5‐PEI 423 complexes display higher transfection efficiencies than PAMAM G4 and PEI‐25k. The complexes possess better serum‐resistant capacity. The G2.5‐PEI 423 has a great potential to be used as a serum‐resistant gene vector. magnified image
Copolyesters of Lactide, Isosorbide, and Terephthalic Acid‐Biobased, Biodegradable, High‐Tg Engineering Plastics
Authors: Kricheldorf Hans R. , Weidner Steffen M. 
Published: February 2013

AbstractVarious copolyesters of lactide, isosorbide, and terephthalic acid are prepared by a two‐step process performed in a “one‐pot” procedure, beginning with an isosorbide‐initiated oligomerization of L‐lactide followed by polycondensation with terephthaloyl chloride using SnCl2 as a catalyst for both steps. The SEC data show the formation of random copolyesters with high polydispersities as a consequence of the relatively high fraction of cyclics proved by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS). The glass‐transition temperatures (89–180 °C) obey an almost linear trend with the molar composition. The thermostability decreases with increasing lactide content. The successful incorporation of phenyl phosphate results in copolyesters of lower inflammability.