bluuebunny/crossref_metadata_2025 huggingface dataset:
An assessment of the ICE6G_C(VM5a) glacial isostatic adjustment model
Authors: Purcell A. , Tregoning P. , Dehecq A.
Published: April 2016

The recent release of the next‐generation global ice history model, ICE6G_C(VM5a), is likely to be of interest to a wide range of disciplines including oceanography (sea level studies), space gravity (mass balance studies), glaciology, and, of course, geodynamics (Earth rheology studies). In this paper we make an assessment of some aspects of the ICE6G_C(VM5a) model and show that the published present‐day radial uplift rates are too high along the eastern side of the Antarctic Peninsula (by ∼8.6 mm/yr) and beneath the Ross Ice Shelf (by ∼5 mm/yr). Furthermore, the published spherical harmonic coefficients—which are meant to represent the dimensionless present‐day changes due to glacial isostatic adjustment (GIA)—contain excessive power for degree ≥90, do not agree with physical expectations and do not represent accurately the ICE6G_C(VM5a) model. We show that the excessive power in the high‐degree terms produces erroneous uplift rates when the empirical relationship of Purcell et al. (2011) is applied, but when correct Stokes coefficients are used, the empirical relationship produces excellent agreement with the fully rigorous computation of the radial velocity field, subject to the caveats first noted by Purcell et al. (2011). Using the Australian National University (ANU) groups CALSEA software package, we recompute the present‐day GIA signal for the ice thickness history and Earth rheology used by Peltier et al. (2015) and provide dimensionless Stokes coefficients that can be used to correct satellite altimetry observations for GIA over oceans and by the space gravity community to separate GIA and present‐day mass balance change signals. We denote the new data sets as ICE6G_ANU.
Impact of Homeowner Association (HOA) landscaping guidelines on residential water use
Authors: Wentz Elizabeth A. , Rode Sandra , Li Xiaoxiao , Tellman Elizabeth M. , Turner B. L.
Published: April 2016

The association between increasing water intensive land‐cover, such as the use of turf grass and trees, and increasing water use is a growing concern for water‐stressed arid cities. Appropriate regulatory measures addressing residential landscaping, such as those applied by Homeowner Associations (HOAs), may serve to reduce municipal water use, joining other water‐use reducing measures under consideration by arid cities. This research assesses quantitatively the role that Covenants, Conditions, and Restrictions (CCRs) applied to landscaping by HOAs play on water consumption. Statistical comparisons and models of n=1973 parcels in Goodyear, Arizona, USA, reveal that: HOA yards have less vegetation cover and those households use less peak‐season water (July) than those households in non‐HOA neighborhoods. This hold true even though the HOA CCRs regulate only the minimum required front‐yard vegetation and most residents maintain more than the minimum vegetation level. Furthermore, front‐yard landscaping tends to be mimicked in the backyard such that total yard landscaping tracks best with total household water use. Results of the study suggest that HOA landscaping regulations have the potential to reduce peak‐season water use by up to 24% if CCRs were to set maximum vegetation regulations rather than minimum and if compliance were enforced. Lowering residential water consumption in this way potentially involves tradeoffs with the cooling effects of vegetation and its consequences on the urban heat island effect, on energy use, and on home values.
The psychology of recycled water: Factors predicting disgust and willingness to use
Authors: Wester Julia , Timpano Kiara R. , Çek Demet , Broad Kenneth
Published: April 2016

Water recycling is increasingly recognized as a critical strategy to maintain sustainable water supplies. Yet public acceptance of water recycling often lags behind. It is unclear the degree to which individuals are aware of the role of disgust in their decisions about recycled water, how important anticipated disgust is to willingness to use when controlling for other factors, and what the most effective method of presenting information about water recycling would be to decrease disgust reactions and increase willingness to use. We used a two‐pronged approach, combining a survey with open‐ended and psychometric measures with an experimental manipulation, in a U.S., web‐based sample (N = 428). Only 2% of participants self‐identified disgust as important to their decisions about recycled water. When measured directly using a Likert scale, however, anticipated disgust was the strongest predictor of willingness to use recycled water when controlling for individual differences that have been shown to impact willingness to use, including a subscale of individual pathogen disgust sensitivity. Finally, participants were exposed to an educational brochure about water reuse framed either affectively or cognitively or were shown a simple, neutral definition. Exposure to either the affectively or cognitively framed brochures lowered anticipated disgust, but did not significantly affect willingness to use recycled water compared to the neutral condition.
Application of array backprojection to tsunami prediction and early warning
Authors: An Chao , Meng Lingsen
Published: April 2016

Teleseismic and static geodetic data have weak constraints on the offshore slip while tsunami data are limited by their availability, so predictions of tsunami waves in the near‐field remain challenging. In this study, we develop a near‐field tsunami prediction approach based on seismic array backprojections (BP). In this approach, the rupture area is first estimated by enclosing the BP radiators. Then slip models with uniform slip are constructed based on statistical scaling relations between rupture area and seismic moment to predict the near‐field tsunami waveforms. The method is applied to the 2011 Tohoku, 2014 Iquique, and 2015 Illapel tsunami events, and the model predictions are compared with tsunami recordings at 57 tidal gauges and nine DART stations. Results show that the average error of arrival time and amplitude nearshore is approximately −15 to +5 min and 0.5 m, respectively, which are sufficiently small for tsunami warning purposes.
Shape‐Memory Topographies on Nickel–Titanium Alloys Trained by Embossing and Pulse Electrochemical Machining
Authors: Frensemeier Mareike , Schirra Dominik , Weinmann Martin , Weber Olivier , Kroner Elmar
Published: April 2016

The two‐way shape‐memory effect (TWSME) in Nickel–titanium (NiTi) alloys is of interest for applications in aerospace, biomedicine, and microengineering due to its reversible shape recovery. In this study, the authors demonstrate two approaches to obtain switchable surface structures using the TWSME. Samples are structured using two surface geometries by either cold embossing, or pulse electrochemical machining (PECM). After planarization, a change from optically smooth to structured and vice versa is observed. The switch is induced through heating and cooling the sample above and below the phase transformation temperature. The protrusions reflect the pattern applied by the two processes. Both methods are promising for preparation of switchable metallic surfaces on larger areas.
Synthetic Self‐Assembled Materials in Biological Environments
Authors: Versluis Frank , van Esch Jan H. , Eelkema Rienk
Published: April 2016

Synthetic self‐assembly has long been recognized as an excellent approach for the formation of ordered structures on the nanoscale. Although the development of synthetic self‐assembling materials has often been inspired by principles observed in nature (e.g., the assembly of lipids, DNA, proteins), until recently the self‐assembly of synthetic molecules has mainly been investigated ex vivo. The past few years however, have witnessed the emergence of a research field in which synthetic, self‐assembling systems are used that are capable of operating as bioactive materials in biological environments. Here, this up‐and‐coming field, which has the potential of becoming a key area in chemical biology and medicine, is reviewed. Two main categories of applications of self‐assembly in biological environments are identified and discussed, namely therapeutic and imaging agents. Within these categories key concepts, such as triggers and molecular constraints for in vitro/in vivo self‐assembly and the mode of interaction between the assemblies and the biological materials will be discussed.
Highly Sensitive and Selective Polyaniline Nanofiber–Based Voltammetric Sensor for the Quantification of Tinidazole
Authors: Jain Rajeev , Karolia Priyanka , Sinha Ankita , Farooq
Published: April 2016

A voltammetric sensor is an effective tool for pharmaceutical analysis due to its simplicity, specificity, sensitivity, fast, cost‐effectiveness, and repetitive measurements. A highly sensitive and selective sensor is fabricated based on a polyaniline‐modified glassy carbon electrode. It is demonstrated that this sensor can be used for the determination of a pharmaceutically important compound tinidazole using square wave voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy. The electrode surface was characterized by scanning electron microscopy. The developed sensor also exhibited good reproducibility and long‐term stability. Polyaniline nanofibers are expected to be a promising material for sensing applications because of the ease of fabrication, excellent electrochemical performance, and high electroactive surface area.
Synthesis of Cyclopentachromans by N‐Heterocyclic Carbene‐Mediated Homoenolate Annulation of Chroman‐3‐ene‐4‐ones
Authors: Krishnan Jagadeesh , Sinu C. R. , Anusree M. , Seetha Lakshmi K. C. , Mayadevi T. S. , Eringathodi Suresh , Nair Vijay
Published: April 2016

An N‐heterocyclic carbene (NHC)‐mediated homoenolate reaction strategy for the efficient synthesis of a wide variety of tricyclic pentenes with potential biological activity is reported.
Investigation of Meyer–Schuster Rearrangement Promoted by a Samarium(III) Triflate/N‐Fluorobenzenesulfonimide Lewis Acid System
Authors: Du Chuan , Wang Xiaoyu , Jin Shengfei , Shi Hui , Li Yangming , Pang Yadong , Liu Yang , Cheng Maosheng , Guo Chun , Liu Yongxiang
Published: April 2016

The acceleration effect from the addition of N‐fluorobenzenesulfonimide (NFSI) to a samarium(III) triflate catalyzed Meyer–Schuster rearrangement under microwave irradiation was studied. Reaction rate plots indicate that the Sm(OTf)3/NFSI system is especially suitable for unreactive substrates towards the Meyer–Schuster rearrangement. The mechanism was probed by a crossover experiment using 18O‐labeled substrates.
TTIP Treaty Negotiations Loom as Investor‐State Dispute Settlement Is Debated
Authors: Mazzoleni Veronica
Published: April 2016

The Transatlantic Trade and Investment Partnership, known by the acronym TTIP, is a proposed trade and investment agreement that is being negotiated between the European Union and the United States.
Physiology of free will
Authors: Hallett Mark
Published: April 2016

Free will is a perception that people have that they choose to make their movements. This perception includes a sense of willing the movement and self‐agency that they are responsible for the movement. If there is a “free will force” that plays a role in movement selection, it should precede movement. There is no evidence for a driving force, and the perception of willing is not fully processed until after the movement. The perceptions of free will likely arise from an interaction between frontal and parietal areas. Free will might be considered to exist if a person's brain is functioning normally without coercion. Ann Neurol 2016;80:5–12
Molekulare Phosphan‐Feststoffkatalysatoren zur Ameisensäurezersetzung in der Bioraffinerie
Authors: Hausoul Peter J. C. , Broicher Cornelia , Vegliante Roberta , Göb Christian , Palkovits Regina
Published: April 2016

Bei der Lävulinsäureherstellung aus Cellulose fällt Ameisensäure als Koppelprodukt an. Dadurch werden eine integrierte Wasserstoffproduktion oder reduktive chemische Umsetzungen möglich. Mit Rutheniumkomplexen beladene phosphorbasierte poröse Polymere erreichen eine hohe Aktivität und Selektivität in der basenfreien Zersetzung von Ameisensäure zu CO2 und H2. Ein polymeres Analogon von 1,2‐Bis(diphenylphosphanyl)ethan (DPPE) hat die höchste katalytische Aktivität und ist unter den Reaktionsbedingungen stabil. Bei wiederholtem Einsatz des Katalysators traten nur ein geringfügiges Auslaugen von Ruthenium und eine langsame Deaktivierung über sieben Zyklen auf. Anwendungsnahe Untersuchungen ergaben außerdem, dass mit diesen Katalysatoren Ameisensäure sogar in rohen Produktmischungen der Lävulinsäureherstellung selektiv zersetzt werden kann.
Like a Parent and a Friend, but Not the Father: A Qualitative Study of Stepfathers’ Experiences in the Stepfamily
Authors: Blyaert Lies , Van Parys Hanna , De Mol Jan , Buysse Ann
Published: April 2016

Research about the experience and position of stepfathers in stepfamilies is scarce. Using data from semi‐structured interviews with eight stepfathers, we aim to explore how stepfathers experience family life and their relationships with their (step)children and extended family members (biological father and grandparents), as well as how they describe their position within the stepfamily. Interpretative phenomenological analysis revealed three main themes: most participants saw themselves ‘like a parent and a friend.’ While none of them considered themselves as ‘the father’ – this position being assigned to the biological father – they described acting like a parent or a father figure in their relationships with the children. Secondly, despite some difficulties in the initial stages of formation of their new families, most participants described a positive evolution over time and were satisfied with their current family situation. Thirdly, the stepfather's positioning towards non‐cohabiting family members such as the biological father and grandparents added complexity but was managed well. Research findings are discussed in light of the current family therapy literature on working with stepfamilies.
Surfactant‐assisted separation of ginkgo flavonoids from Ginkgo biloba leaves using leaching and foam fractionation
Authors: Jiao Meng , Wu Zhao Liang , Liu Yan , Liu Wei , Li Rui
Published: April 2016

A surfactant can be used as solubilizer in leaching or collector in foam fractionation. However, at the present, there are not any references on the two synergetic effects of it for improving the separation efficiency of foam fractionation. So in this work, a surfactant‐assisted foam fractionation technology was developed to separate ginkgo flavonoids (GF) from the leaching solution of Ginkgo biloba leaves, where the surfactant played the dual roles of solubilizer and collector. The solubilization mechanism of GF by the surfactant of sodium dodecyl sulfate was mainly attributed to electrostatic attraction and hydrogen bonds. The GF concentration reached 1.13 mg/mL under the optimal leaching conditions determined by response surface methodology. A two‐stage foam fractionation technology was developed for effectively enriching GF from the leaching solution, where the residual solution of the first stage was used as the loading solution of the second stage and the foamate of the second stage was used as the feeding solution of the first stage. Both the enrichment ratio and the recovery percentage of GF were improved, and they were 5.82% and 76.25%, respectively, under the optimum conditions. Finally, seven ingredients of GF in the foamate were identified by using HPLC‐MS/MS. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Rheological behavior of polycarbonate/ultrafine octaphenyl silsesquioxane (OPS) composites
Authors: Cheng Baofa , Li Xiangmei , Hao Jianwei , Yang Rongjie
Published: April 2016

Polycarbonate (PC)/ultrafine polyhedral oligomeric octaphenyl silsesquioxane (OPS) composites were prepared by melt mixing method. The morphology and rheological behavior of PC/ultrafine OPS composites were investigated by scanning electron microscopy (SEM) melt indexer, high pressure capillary rheometer, and strain‐controlled rheometer. The SEM results show that ultrafine OPS is dispersed in PC as the size of submicron and has a good dispersion in PC matrix, and a certain extent compatibility between PC and ultrafine OPS is found. OPS aggregation is found through the cross section at high ultrafine OPS content. The results of melt flow index (MFI) and capillary rheometer indicate that ultrafine OPS can effectively decrease the apparent viscosity and improve the flow property and processability of PC matrix as a lubricant. The oscillatory rheological analysis indicates that the storage modulus increases with increasing OPS content, and the appeared platform of storage modulus exhibits the solid‐like behavior and the formation of three‐dimensional network in the composites. The complex viscosity of PC/OPS composite shows a quasi‐Newtonian regime at low OPS content and a typical shear‐thinning behavior at high OPS content. The Cole–Cole, Han, and van Gurp plots show that ultrafine OPS particle is compatible with PC at low content (≤3 wt %), and interaction between particle and particle is the major factor when OPS at high content (≥6 wt %). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43638.
A new biobased plasticizer for poly(vinyl chloride) based on epoxidized cottonseed oil
Authors: Carbonell‐Verdu Alfredo , Garcia‐Sanoguera David , Jordá‐Vilaplana Amparo , Sanchez‐Nacher Lourdes , Balart Rafael
Published: April 2016

The use of epoxidized cottonseed oil as plasticizer for poly(vinyl chloride) was studied. The plasticizer content was set to 70 phr and the optimum isothermal curing conditions were studied in the temperature range comprised between 160 and 220 °C with varying curing times in the 7.5–17.5 min range. The influence of the curing conditions on overall performance of cured plastisols was followed by the evolution of mechanical properties (tensile tests with measurements of tensile strength, elongation at break, and modulus), change in color, surface changes of fractured samples by scanning electron microscopy (SEM), thermal transitions by differential scanning calorimetry, and migration in n‐hexane. The optimum mechanical features of cured plastisols are obtained for curing temperatures in the 190–220 °C range. For these curing conditions, fractography analysis by SEM gives evidences of full curing process as no PVC particles and free plasticizer can be found. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43642.
Elastic constants of lamellar and interlamellar regions in α and mesomorphic isotactic polypropylene by AFM indentation
Authors: Picu R. C. , Osta A. R.
Published: April 2016

A study of the nanoscale mechanical properties of isotactic mesomorphic and semi‐crystalline polypropylene (iPP) is presented. Two iPPs produced with metallocene and Ziegler‐Natta catalyst polymerization are used. The resulting fibers are characterized by wide angle X‐ray scattering, small‐angle X‐ray scattering (SAXS), and Raman spectroscopy. The spatial variability of the percentage crystallinity is evaluated based on the SAXS data. AFM indentation is performed to measure the elastic modulus of the fibers in the direction perpendicular and parallel to the fiber axis. Since the AFM probing is performed on a scale larger than the lamellar thickness, a statistical analysis of the AFM and SAXS data is necessary to infer the elastic moduli of the α crystals and of the inter‐lamellar regions. The elastic modulus of the crystalline lamellae in the direction perpendicular to the c‐axis of the α crystal probed in compression is estimated at approximately 3.3 GPa, while the effective modulus of the interlamellar regions ranges from 1.5 to 2.2 GPa. The method proposed can be applied to other material systems with similar layered structure to measure elastic moduli or hardness on length scales smaller than the resolution of the indentation test. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43649.
Exploring interdisciplinary relationships between linguistics and information retrieval from the 1960s to today
Authors: Engerer Volkmar
Published: April 2016

This article explores how linguistics has influenced information retrieval (IR) and attempts to explain the impact of linguistics through an analysis of internal developments in information science generally, and IR in particular. It notes that information science/IR has been evolving from a case science into a fully fledged, “disciplined”/disciplinary science. The article establishes correspondences between linguistics and information science/IR using the three established IR paradigms—physical, cognitive, and computational—as a frame of reference. The current relationship between information science/IR and linguistics is elucidated through discussion of some recent information science publications dealing with linguistic topics and a novel technique, “keyword collocation analysis,” is introduced. Insights from interdisciplinarity research and case theory are also discussed. It is demonstrated that the three stages of interdisciplinarity, namely multidisciplinarity, interdisciplinarity (in the narrow sense), and transdisciplinarity, can be linked to different phases of the information science/IR‐linguistics relationship and connected to different ways of using linguistic theory in information science and IR.
Unsicherheiten bei der Quantifizierung von Hochwasser‐Schadenspotenzialen
Authors: Schwarz Jochen , Maiwald Holger , Kaufmann Christian
Published: April 2016

Die Ermittlung von Hochwasser‐Schadenspotenzialen bei Nutzen‐Kosten‐Analysen erfolgt in den einzelnen Bundesländern meist mit herkömmlichen nutzungsorientierten Schadensmodellen. Dabei geben Schadensfunktionen einen Erwartungswert (Mittelwert) für den zu erwartenden Schaden in Abhängigkeit von der Nutzung und den hochwasserspezifischen Einwirkungsparametern an. Die große Streubreite der real auftretenden Schäden wird dabei vernachlässigt.

Im Beitrag werden die Auswirkungen der in diesen Modellen nicht berücksichtigten verletzbarkeitsbestimmenden Bauwerksparameter und verschiedener möglicher (flächennutzungskonformer) Bauwerksbestände durch Monte‐Carlo‐Simulationen untersucht.

Für diese Simulationen werden mit dem verletzbarkeitsorientierten, mikroskaligen EDAC‐Hochwasserschadensmodell für reale Überflutungsszenarien die Streubreiten der potenziellen Verluste ermittelt.

Die Ergebnisse veranschaulichen, dass diese Streubreiten in den Verlusten im Rahmen von Nutzen‐Kosten‐Analysen mit berücksichtigt werden sollten.

Uncertainties in the quantification of flood damage potential

The determination of flood damage potential in cost‐benefit analyses is carried out in the individual federal states mostly with conventional use‐oriented damage models. This type of damage functions provides expected values (average values) for the losses depending on the use and flood‐specific impact parameters. The large scatter of reported losses is neglected.

The paper considers the impact of vulnerability determining building parameter and different possible (use compliant) building stocks on these models.

On the basis of Monte Carlo simulations, the scatter of the potential losses is calculated applying the vulnerability based, microscale EDAC‐flood damage model for real flooding scenarios.

The results illustrate that these uncertainties of the prognosis should be considered in the loss assessment and in particular for the scope of cost‐benefit decisions.
Die Tücken der Selbstheilung bei Weißen Wannen
Authors: Bastert Heinrich
Published: April 2016

Planung und Ausführung wasserundurchlässiger Betonkonstruktionen (WU‐Konstruktionen) sind in Deutschland seit 2003 in der WU‐Richtlinie des Deutschen Ausschusses für Stahlbeton e. V. (DAfStb) geregelt. Zu den Grundlagen der Bemessung von WU‐Konstruktionen nach WU‐Richtlinie gehört die Wahl eines Entwurfsgrundsatzes. Aus wirtschaftlichen Gründen wird oft der Entwurfsgrundsatz der Selbstheilung von Rissen bevorzugt. In diesem Beitrag werden Grundlagen des Selbstheilungsprozesses genannt und ihre Auswirkungen auf die Gebrauchstauglichkeit der WU‐Konstruktion aufgezeigt.

Design of watertight concrete structures using autogenous healing of cracks

The design and execution of watertight concrete structures in Germany is regulated by the DAfStb guideline on watertight concrete structures from 2003 (WU‐Richtlinie). Fundamentals of the design of watertight concrete structures according to the WU‐Richtlinie refer to several options to solve the problem of possible cracks in concrete. Most practitioners prefer autogenous healing of cracks because it is an efficient and economical way to solve these problems. This paper provides some basic information on the autogenous healing process and the effects on the usability of watertight structures.
Embryo‐Fetal Developmental Toxicity Studies with Pregabalin in Mice and Rabbits
Authors: Morse Dennis C.
Published: April 2016

Pregabalin was evaluated for potential developmental toxicity in mice and rabbits. Pregabalin was administered once daily by oral gavage to female albino mice (500, 1250, or 2500 mg/kg) and New Zealand White rabbits (250, 500, or 1250 mg/kg) during organogenesis (gestation day 6 through 15 [mice] or 6 through 20 [rabbits]). Fetuses were evaluated for viability, growth, and morphological development. Pregabalin administration to mice did not induce maternal or developmental toxicity at doses up to 2500 mg/kg, which was associated with a maternal plasma exposure (AUC0–24) of 3790 μg•hr/ml, ≥30 times the expected human exposure at the maximum recommended daily dose (MRD; 600 mg/day). In rabbits, treatment‐related clinical signs occurred at all doses (AUC0–24 of 1397, 2023, and 4803 μg•hr/ml at 250, 500, and 1250 mg/kg, respectively). Maternal toxicity was evident at all doses and included ataxia, hypoactivity, and cool to touch. In addition, abortion and females euthanized moribund with total resorption occurred at 1250 mg/kg. There were no treatment‐related malformations at any dose. At 1250 mg/kg, compared with study and historical controls, the percentage of fetuses with retarded ossification was significantly increased and the mean number of ossification sites was decreased, which correlated with decreased fetal and placental weights, consistent with in utero growth retardation. Therefore, the no‐effect dose for developmental toxicity in rabbits was 500 mg/kg, which produced systemic exposure approximately 16‐times human exposure at the MRD. These findings indicate that pregabalin, at the highest dose tested, was not teratogenic in mice or rabbits
Zur Ermüdung von Beton und Stahlfaserbeton
Authors: Heek Peter , Mark Peter
Published: April 2016

Zur Beurteilung des Ermüdungsverhaltens von Werkstoffen wie Beton und Stahlfaserbeton unter zyklischer Beanspruchung konstanter Amplitude haben sich WÖHLERlinien etabliert. Im Einstufen‐Schwingversuch wird dabei eine Materialprobe einer zyklischen Beanspruchung bis zum Bruch ausgesetzt und die Anzahl aufnehmbarer Lastspiele logarithmiert als Funktion der Ermüdungslast aufgetragen. In der Literatur existiert eine Vielzahl empirischer WÖHLERlinien für z. B. normal‐ und hochfeste Betone ohne und mit Faserzusatz unter Schwell‐ oder Wechselbeanspruchung. Ein universell gültiger Ansatz fehlt hingegen bisher. Im Beitrag wird das Ermüdungsverhalten von Beton und Stahlfaserbeton verglichen und ein energetisches Duktilitätsmaß vorgestellt, das zur Klassifizierung der Betone geeignet ist und eine einheitliche Beschreibung des funktionalen Zusammenhanges von Bruchlastspielzahl und Ermüdungslast ermöglicht. Die mechanische Basis des Duktilitätsmaßes erlaubt zudem insbesondere für zyklisch biegezugbeanspruchte Stahlfaserbetone die gezielte Optimierung ermüdungsrelevanter Parameter wie Fasertyp und ‐menge. Anhand von Versuchsergebnissen aus der Literatur werden Genauigkeit und Allgemeingültigkeit des neuen Ansatzes verifiziert und an Beispielen vorgestellt.

Fatigue of plain and steel fibre reinforced concrete

To assess fatigue‐life of plain and steel fibre reinforced concrete Wöhler‐ or rather SN‐curves are well established. Those curves providing information about logarithmised numbers of cycles until failure as a function of constant amplitude loading can easily be derived via testing. In literature, a huge number of empirical SN approaches are available, valid either for normal or high‐performance concrete containing variable amounts of fibres for instance. However, a more general approach is still missing. Subsequently, fatigue life of plain and steel fibre reinforced concrete at constant amplitude loading is contrasted yielding to modified but universally valid SN‐curves containing a new toughness index. The mechanically based toughness index is suitable to distinguish between plain and fibre reinforced concrete and allows for the optimization of fibre characteristics like type and dosage to ensure maximum fatigue life. Finally, the presented SN approach is verified using test data from literature. The results are in good accordance on average.
Calorespirometric feeding control enhances bioproduction from toxic feedstocks—Demonstration for biopolymer production out of methanol
Authors: Rohde Maria‐Teresa , Paufler Sven , Harms Hauke , Maskow Thomas
Published: April 2016

The sustainable production of fuels and industrial bulk chemicals by microorganisms in biotechnological processes is promising but still facing various challenges. In particular, toxic substrates require an efficient process control strategy. Methanol, as an example, has the potential to become a major future feedstock due to its availability from fossil and renewable resources. However, besides being toxic, methanol is highly volatile. To optimize its dosage during microbial cultivations, an innovative, predictive process control strategy based on calorespirometry, i.e., simultaneous measurements of heat and CO2 emission rates, was developed. This rarely used technique allows an online‐estimation of growth parameters such as the specific growth rate and substrate consumption rate as well as a detection of shifts in microbial metabolism thus enabling an adapted feeding for different phases of growth. The calorespirometric control strategy is demonstrated exemplarily for growth of the methylotrophic bacterium Methylobacterium extorquens on methanol and compared to alternative control strategies. Applying the new approach, the methanol concentration could be maintained far below a critical limit, while increased growth rates of M. extorquens and higher final contents of the biopolymer polyhydroxybutyrate were obtained. Biotechnol. Bioeng. 2016;113: 2113–2121. © 2016 Wiley Periodicals, Inc.
Randomized multicentre trial comparing external and internal pancreatic stenting during pancreaticoduodenectomy
Authors: Jang J-Y , Chang Y R , Kim S-W , Choi S H , Park S J , Lee S E , Lim C-S , Kang M J , Lee H , Heo J S
Published: April 2016

Background

There is no consensus on the best method of preventing postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD). This multicentre, parallel group, randomized equivalence trial investigated the effect of two ways of pancreatic stenting after PD on the rate of POPF.

Methods

Patients undergoing elective PD or pylorus-preserving PD with duct-to-mucosa pancreaticojejunostomy were enrolled from four tertiary referral hospitals. Randomization was stratified according to surgeon with a 1 : 1 allocation ratio to avoid any related technical factors. The primary endpoint was clinically relevant POPF rate. Secondary endpoints were nutritional index, remnant pancreatic volume, long-term complications and quality of life 2 years after PD.

Results

A total of 328 patients were randomized to the external (164 patients) or internal (164) stent group between August 2010 and January 2014. The rates of clinically relevant POPF were 24·4 per cent in the external and 18·9 per cent in the internal stent group (risk difference 5·5 per cent). As the 90 per cent confidence interval (−2·0 to 13·0 per cent) did not fall within the predefined equivalence limits (−10 to 10 per cent), the clinically relevant POPF rates in the two groups were not equivalent. Similar results were observed for patients with soft pancreatic texture and high fistula risk score. Other postoperative outcomes were comparable between the two groups. Five stent-related complications occurred in the external stent group. Multivariable analysis revealed that soft pancreatic texture, non-pancreatic disease and high body mass index (23·3 kg/m2 or above) predicted clinically relevant POPF.

Conclusion

External stenting after PD was associated with a higher rate of clinically relevant POPF than internal stenting. Registration number: NCT01023594 (https://www.clinicaltrials.gov).
Biophysikalische Chemie – vom Einzelmolekül zum Verständnis komplexer biologischer Maschinen
Authors: Winter Roland
Published: April 2016

Während Chemie, Biologie und Physik sich im letzten Jahrhundert weitgehend auseinandergelebt haben, ist in diesen Jahren die Tendenz zu sehen, dass sie wieder aufeinander zugehen und einander befruchten. Dies ist umso wichtiger, als es in der nun eingetretenen Postgenom‐Ära darum geht, die Regulation der Genaktivität und die Funktion und Interaktion der Proteine und anderer Biomoleküle in der Zelle zu verstehen, wodurch das molekulare Verständnis der Lebensvorgänge immer mehr in den Vordergrund naturwissenschaftlicher Forschungsarbeiten rückt.
Investigations and Experiments of Variances Filtering Technology in the Ensemble Data Assimilation
Authors: Bai‐Nian LIU , Wei‐Min ZHANG , Xiao‐Qun CAO , Yan‐Lai ZHAO , Qun‐Bo HUANG , Yu LUO
Published: April 2016

An experimental Ensemble Data Assimilation (YH‐EDA) system has been built with 10 ensemble members based on the operational YH4DVAR system. The system can provide flow‐dependent background‐error variances, which are superior to the operational ones both in structure and magnitude. However, the finite ensemble size implies a detrimental sampling noise for the variances estimation. To solve this problem, a spectral filtering technique is implemented to formulate a low‐passing filter. Taking into account the typical horizontal length scales of noise and signal, the filter can eliminate the sampling noise while extracting the signal of interest. In the ensemble variance filtering experimentations of the 9th typhoon “Jebi” in 2013, our results show that the 10‐members' filtered variances exhibit better performance than 30‐members's estimation. The successful implementation of the spectral filtering reduces the requirement of large ensemble size of Ensemble Data Assimilation system, which indicates that spectral filtering has become an important and necessary technology in EDA operational implementation.
Evaluating p97 Inhibitor Analogues for Potency against p97–p37 and p97–Npl4–Ufd1 Complexes
Authors: Gui Lin , Zhang Xiaoyi , Li Kelin , Frankowski Kevin J. , Li Shan , Wong Daniel E. , Moen Derek R. , Porubsky Patrick R. , Lin Henry J. , Schoenen Frank J. , Chou Tsui‐Fen
Published: April 2016

We previously found that the p97 cofactor, p47, significantly decreased the potency of some ATP‐competitive p97 inhibitors such as ML240 [2‐(2‐amino‐1H‐benzo[d]imidazol‐1‐yl)‐N‐benzyl‐8‐methoxyquinazolin‐4‐amine] and ML241 [2‐(2H‐benzo[b][1,4]oxazin‐4(3H)‐yl)‐N‐benzyl‐5,6,7,8 tetrahydroquinazolin‐4‐amine]. In this study, we aimed to evaluate inhibitor potencies against two additional p97 cofactor complexes, p97–p37 and p97–Npl4–Ufd1. We focused on these two cofactor complexes, because the protein sequence of p37 is 50 % identical to that of p47, and the Npl4–Ufd1 heterodimer (NU) is the most‐studied p97 cofactor complex. We screened 200 p97 inhibitor analogues for their ability to inhibit the ATPase activity of p97 alone and of p97–p37 and p97–NU complexes. In contrast to the effect of p47, p37 and NU did not significantly change the potencies of most of the compounds. These results highlight differences among p97 cofactors in influencing p97 conformation and effects of inhibitors on p97 complexes, as compared to p97 alone. Continued efforts are needed to advance the development of complex‐specific p97 inhibitors.
The role of infarct transmural extent in infarct extension: A computational study
Authors: Leong Chin‐Neng , Lim Einly , Andriyana Andri , Al Abed Amr , Lovell Nigel Hamilton , Hayward Christopher , Hamilton‐Craig Christian , Dokos Socrates
Published: April 2016

Infarct extension, a process involving progressive extension of the infarct zone (IZ) into the normally perfused border zone (BZ), leads to continuous degradation of the myocardial function and adverse remodelling. Despite carrying a high risk of mortality, detailed understanding of the mechanisms leading to BZ hypoxia and infarct extension remains unexplored. In the present study, we developed a 3D truncated ellipsoidal left ventricular model incorporating realistic electromechanical properties and fibre orientation to examine the mechanical interaction among the remote, infarct and BZs in the presence of varying infarct transmural extent (TME). Localized highly abnormal systolic fibre stress was observed at the BZ, owing to the simultaneous presence of moderately increased stiffness and fibre strain at this region, caused by the mechanical tethering effect imposed by the overstretched IZ. Our simulations also demonstrated the greatest tethering effect and stress in BZ regions with fibre direction tangential to the BZ–remote zone boundary. This can be explained by the lower stiffness in the cross‐fibre direction, which gave rise to a greater stretching of the IZ in this direction. The average fibre strain of the IZ, as well as the maximum stress in the sub‐endocardial layer, increased steeply from 10% to 50% infarct TME, and slower thereafter. Based on our stress–strain loop analysis, we found impairment in the myocardial energy efficiency and elevated energy expenditure with increasing infarct TME, which we believe to place the BZ at further risk of hypoxia. Copyright © 2016 John Wiley & Sons, Ltd.
Graphene‐Wrapped Graphitic Carbon Hollow Spheres: Bioinspired Synthesis and Applications in Batteries and Supercapacitors
Authors: Song Lei , Xin Sen , Xu Da‐Wei , Li Hui‐Qin , Cong Huai‐Ping , Yu Shu‐Hong
Published: April 2016

Inspired by the egg‐like yolk–shell structure, a novel kind of graphene‐wrapped graphitic hollow carbon spheres (G‐graphitic HCS) was designed and fabricated by iron‐catalyzed carbonization of double‐coated polystyrene (PS) spheres. Herein, a thin carbon shell and hollow, hierarchically porous G‐graphitic HCS facilitate ionic transport, while also providing more active sites for the storage of ions. Both graphitic components result in a seamless and highly efficient transmission pathway for electrons. Thus, G‐graphitic HCS demonstrate admirable multifunctions in energy‐storage devices, including lithium batteries, sodium batteries, and supercapacitors. It delivers an unprecedentedly high initial discharge capacity of 2007 mA h g−1 at 0.1 A g−1, and preserves 92.4 % of the initial charge capacity after 100 cycles in a prototype lithium half‐cell. The present concept may shed light on designing the key materials for next‐generation energy‐storage devices.
Interpretation of Spectroscopic Markers of Hydrogen Bonds
Authors: Scheiner Steve
Published: April 2016

Quantum calculations are used to examine whether an AH⋅⋅⋅D H‐bond is unambiguously verified by a downfield shift of the bridging proton's NMR signal or a red (or blue) shift of the AH stretching frequency in the IR spectrum. It is found that such IR band shifts will occur even if the two groups experience weak or no attractive force, or if they are drawn in so close together that their interaction is heavily repulsive. The mere presence of a proton‐acceptor molecule can affect the chemical shielding of a position occupied by a protondonor by virtue of its electron density, even if there is no H‐bond present. This density‐induced shielding is heavily dependent on position around the proton–acceptor atom, and varies from one group to another. Evidence of a hydrogen bond rests on the measurement of a proton deshielding in excess of what is caused purely by the presence of the proton acceptor species.
A lower bound on achievable rate of MRT precoding in multicell multiuser massive MIMO networks with Rician flat fading
Authors: Kazemi Mohammad , Aghaeinia Hassan
Published: April 2016

A multicell multiuser massive multiple‐input‐multiple‐output (MIMO) network with Rician flat fading is considered. Given channel reciprocity, non‐orthogonal uplink channel training in conjunction with minimum mean square error channel estimation at the base stations are used to acquire channel state information. In the forward link, using maximal ratio transmission precoding, base stations send data to corresponding users. In this paper, first, a closed‐form expression for signal to interference and noise ratio and a lower bound on achievable rate are obtained for arbitrary number of base station antennas. Then, using random matrix theory, a simplified approximate expression for large number of base station antennas (i.e., massive MIMO scenario) are calculated. This simplified expression shows that in a multicell multiuser massive MIMO network with Rician flat fading, like Rayleigh fading, as the number of base station antennas goes to infinity, the effects of uncorrelated noise and intercell and intracell interferences tend to zero. The only factor limiting the performance of system is the correlated intercell interference, that is, pilot contamination, due to non‐orthogonality of channel training sequences in adjacent cells. Numerical results show that our obtained closed‐form expression is a good lower bound on sum‐rate for various system parameters. Copyright © 2016 John Wiley & Sons, Ltd.
Antinociceptive Interactions Between Meloxicam and Gabapentin in Neuropathic Pain Depend on the Ratio used in Combination in Rats
Authors: Espinosa‐Juárez Josué Vidal , Jaramillo‐Morales Osmar Antonio , Corona‐Ramos Janette Nallely , Medina‐López José Raúl , López‐Muñoz Francisco Javier
Published: April 2016

Preclinical Research

Neuropathic pain is particularly difficult to treat because of its diverse etiologies and underlying pathophysiological mechanisms. Drug combinations have been proposed to effectively treat some neuropathies. In the present study the interaction of five combinations of meloxicam and gabapentin, were studied to assess the possible synergistic antinociceptive response in neuropathic pain using the von Frey and acetone tests in rat models. Coadministration of meloxicam and gabapentin increased the antihyperalgesic or antiallodynic effects as compared with the compounds administered alone. The area under the curve (AUC) of the antihyperalgesic effects produced by the combination of the two drugs was generally similar to the theoretical sum of effects produced by each drug alone. However, the AUC of the antiallodynic effect produced by one combination (meloxicam 1.0 mg/kg + gabapentin 10 mg/kg) was greater than the theoretical sum of the effects produced by each drug alone. The type of final interaction on the drug combinations can be additive or cause potentiation of antinociceptive effects and depends on the proportion of each compound used in dosing. Drug Dev Res 77 : 134–142, 2016. © 2016 Wiley Periodicals, Inc.
Soil physical properties response to grassland conversion from cropland on the semi‐arid area
Authors: Wu Gao‐Lin , Liu Yu , Fang Nu‐Fang , Deng Lei , Shi Zhi‐Hua
Published: April 2016

Soil physical properties crucially affect vegetation restoration on the semi‐arid Loess Plateau. Understanding how converting cropland into grassland affects soil physical properties is essential throughout a long‐term natural vegetation restoration chronosequence. The objectives of this study were to determine the effects of naturally restored grassland from cropland (wheat) on soil physical properties over time. Hence, we analysed the effects on various soil physical properties at different restoration ages (0, 5, 15 and 30 years). Our results revealed that soil physical properties changed dynamically in response to the land use change over time. Grassland restoration increases soil texture coarseness in the upper soil layer (0–5 cm). After a 15‐year restoration, soil hydraulic conductivity attained the maximum measured value, but in restoration age (to 30 years) did not further improve soil hydraulic conductivity. Restoration increased the field capacity and the soil water content under the restored grassland when compared with the cropland, but increases were not linearly related to the restoration age. Our study suggests that converting cropland into grassland improved the soil structure and soil–water conditions, and that the first 15 years of restoration was sufficient in order to achieve most of the improvements in soil physical properties. Our results will be helpful in providing soil hydraulic parameters to other researchers with the aim of improving the restored grassland to become more effective and sustainable on the semi‐arid area. Copyright © 2016 John Wiley & Sons, Ltd.
Potential of grass invasions in desert shrublands to create novel ecosystem states under variable climate
Authors: Yu Kailiang , Okin Gregory S. , Ravi Sujith , D'Odorico Paolo
Published: April 2016

The invasion of exotic grasses into shrublands is a major disturbance to dryland ecosystems. The presence of exotic grasses enhances the occurrence of wildfire in landscapes that had not evolved in the presence of fire, leading to high rates of mortality of the native vegetation. Exotic grasses could be more prone to water stress and mortality than the shrubs they replaced and may not establish during drought, facts that are crucial in ecosystems undergoing increased climatic variability. Here, we develop a process‐based modelling framework to investigate the complex dynamics resulting from the introduction of exotic grasses under variable climate. We find that the system converges towards different steady states, depending on the magnitude of climatic variability. While in the absence of climate fluctuations the shrubland state is replaced by an exotic grassland, interannual climate variability may inhibit grass invasion and stabilize the shrubland state. However, climatic variability also gives rise to a novel third, unvegetated state, with grass invasion being followed by drought, grass mortality and intense soil erosion. Most of the research on climate change effects on ecosystems has historically concentrated on the ecological impact of shifts in mean climate conditions. This study shows that changes in the variance are also important when shifts in vegetation composition (e.g. species invasions) result in different susceptibility to climatic variability. In the presence of random climate fluctuations, ecosystems can display steady states that differ from those that would exist under a constant climate or with a climate trend. Copyright © 2016 John Wiley & Sons, Ltd.
Multiple‐Metal (De‐)Hydrogenation‐Catalysed Processes
Authors: Ventura‐Espinosa David , Mata Jose A.
Published: April 2016

The use of different metals acting together in a synergistic way allows synthetic transformations that are not achievable by other means. Metal cooperation becomes important in catalytic processes for the synthesis of compounds with sophisticated structures or for difficult transformations. Rational design of multiple‐metal‐catalysed processes requires that the metal complexes and reaction conditions are compatible, which in general is not straightforward. A key feature for success found in all systems involving multimetallic processes is catalyst stability. The use of robust metal complexes increases the probability of success in the search for tandem catalytic processes. This microreview is based on the recent and most important findings of multiple‐metal‐catalysed processes that have involved (de‐)hydrogenation reactions. The field constitutes a research area that is full of potential, and it can be foreseen that relevant applications will be described in the near future.