bluuebunny/crossref_metadata_2025 huggingface dataset:
Tribological behavior of DLC and hard coatings against aluminium based materials
Authors: Nehrkorn S. , Rupprecht C. , Wielage B. , Lampke T.
Published: September 2010

Im Leichtbau werden zunehmend massiv umgeformte Bauteile aus hochfestem Aluminium angewendet. Aufgrund ökonomischer und ökologischer Aspekte bei der Umformung ist ein Einsatz von wenig bzw. keinen Schmiermitteln und eine Modifizierung der Werkzeugoberflächen notwendig. Die richtige Auswahl des Beschichtungswerkstoffs ist entscheidend für das Reibverhalten im Kontakt mit hochfesten Aluminiumwerkstoffen und somit ausschlaggebend für die Standzeitverbesserung von Umformwerkzeugen. Zur Untersuchung des tribologischen Verhaltens von verschiedenen Beschichtungskonzepten wurden Proben mittels PVD‐ (Physical Vapour Deposition) und CVD‐Verfahren (Chemical Vapour Deposition) mit verschiedenen Schichtsystemen beschichtet, charakterisiert und mit dem unbeschichteten Substrat 1.3343 (HS6‐5‐3) verglichen. Die Charakterisierung des tribologischen Verhaltens erfolgte durch Scratch‐ und Stift‐Scheibe‐Tests gegen eine Auswahl hochfester Aluminiumwerkstoffe mit und ohne Schmierstoffeinsatz. Zur Oberflächencharakterisierung diente das Tastschnittverfahren. Bei Verwendung von Schmierstoff verbessern die Beschichtungen das Reibverhalten im Vergleich zum Substrat nur unwesentlich. Dagegen reduzieren die DLC‐basierten Schichtsysteme unter trockenen Bedingungen den Reibwert um bis zu 74% gegenüber Stahl. Den geringsten Reibkoeffizient gegen die drei ausgewählten Aluminiumwerkstoffe unter trockenen Bedingungen besitzt das Schichtsystem “Plasmanitrieren + DLC”.

The use of high‐strength aluminium alloys for massive forming parts plays an increasing role in lightweight construction. The usage of less/without lubricant during massive forming and tool surface modification operations are significantly important because of the economical and ecological aspects. Selection of the high wear resistance material, which is in contact with high‐strenght aluminum alloys, is curial for improving the service life of the forming tools. In this study, coatings were deposited on steel substrate 1.3343 (HS6‐5‐3) by PVD (Physical Vapour Deposition) and CVD (Chemical vapor deposition) techniques. The frictional behaviour of coating systems was characterized by a pin‐on‐disk tribometer with and without lubricant conditions. Surface profilometry was used to compare the surface topography of the coatings. The coating systems doesn't show remarkably tribological improvement in comparison to the steel 1.3343 under lubricant conditions. Wear test results showed that the DLC‐based coatings reduce the friction coefficient by up to 74% compared to steel under dry conditions. It has been found that the best performance of tribological system without lubricant improved with the type of plasma nitriding + DLC coating system.
Experimental investigation and numerical simulation of the incremental deformation of a 42CrMo4 steel
Authors: Shutov A. V. , Kuprin C. , Ihlemann J. , Wagner M. F.‐X. , Silbermann C.
Published: September 2010

In dieser Arbeit werden die Verfestigungseigenschaften des Stahls 42CrMo4 untersucht. Die experimentelle Basis wird durch eine Reihe von Torsionsversuchen an dünnwandigen Rohrproben gebildet. Dabei werden Schubverzerrungen bis zu 160% erreicht. Der Werkstoff weist bei einer Umkehr der Belastungsrichtung einen ausgeprägten Bauschinger‐Effekt auf. Um diesen nichtlinearen Effekt adäquat zu erfassen, wird ein bereits existierendes Modell der Viskoplastizität von Shutov und Kreißig verallgemeinert. Die Verallgemeinerung besteht in der Einführung von zusätzlichen inneren Variablen sowie der Modifikation der entsprechenden Evolutionsgleichungen. Ein Teil der Experimente wird bei der Identifikation der Materialparameter verwendet. Die restlichen Experimente dienen der Validierung des erzielten Parametersatzes.

In this work we analyze the strain hardening behaviour of a 42CrMo4 steel. The corresponding experimental data are obtained by a series of torsion tests on thin‐walled tubes. In certain experiments the shear strains range up to 160 percent. When the strain path is reversed, the material exhibits a distinct Bauschinger effect. In order to describe this nonlinear effect, we generalize an existing model of finite strain viscoplasticity proposed by Shutov and Kreißig. The generalization consists of the introduction of additional internal variables and of a modification of corresponding evolution equations. A subset of the experimental data is used for the identification of the material parameters. The rest of the data serves the validation of the resulting set of material parameters.
Investigation into friction coefficients of matched EN AW‐6082 specimens including qualitative reliability and applicability of bolted connections
Authors: Leidich E. , Schuller S. , Gröber D. , Lang H. , Brůžek B.
Published: September 2010

Für die Auslegung von Schraubenverbindungen und deren Zuverlässigkeit sind Reibwerte von wesentlicher Bedeutung. Eine fehlerhafte Bewertung der vorhandenen Reibbedingungen kann zum Versagen der Schraubenverbindung führen. Mögliche Versagensursachen werden unter Nutzung der Fehlerbaumanalyse (FTA – Fault Tree Analysis) diskutiert. Mittels experimenteller Reibkraftmessungen bei tangentialer Schubbeanspruchung wurden Reibwerte für unterschiedliche Oberflächenmerkmale (Rauheiten, Welligkeiten) und Fertigungsbedingungen am Beispiel der Aluminiumlegierung EN AW6082 T6 untersucht. Es werden Empfehlungen für die Festlegung von Reibwerten angegeben.

The friction coefficient is an important and essential property for designing preloaded bolted connections as well as their reliability. An inaccurate quantification can cause failure of the bolted connections. Possible causes of failure are discussed by using Fault Tree Analysis (FTA). Friction coefficients were determined by evaluating experimental of torsion load regarding several surfaces (roughness, waviness) and manufacturing conditions using the example of friction between 6082 T6 aluminium specimens. Recommendations for application of friction coefficients are given.
Robust servo control of a novel type 1 diabetic model
Authors: Kovács L. , Kulcsár B. , György A. , Benyó Z.
Published: September 2010

Robust servo control of a model‐based biomedical application is presented in the article. The glucose–insulin control of type 1 diabetic patients is considered to be solved using the results of post‐modern robust control principles.

The paper uses a recently published glucose–insulin model and presents the transformation of the model to describe the dynamics of type 1 diabetes mellitus. The nonlinear plant is then linearized at a given steady state point. In order to characterize the uncertainty around the nominal model in frequency domain, a parametric nonlinear model sensitivity analysis is performed using gridding method. The aim of the paper is to underline the viability of the robust servo, linear µ‐control algorithm tested in highly nonlinear closed‐loop simulation environment. Using two degree‐of‐freedom robust controller, the structured singular value of the closed‐loop is designed to fulfill the robust performance requirements and assure glucose level control.

Glucose level tracking is ensured under simulated and realistic exogenous meal disturbances. Copyright © 2010 John Wiley & Sons, Ltd.
Wage bargaining as an optimal control problem: A dynamic version of the right‐to‐manage model
Authors: Guerrazzi Marco
Published: September 2010

This paper aims at representing wage bargaining as an optimal control problem. Specifically, assuming that employment follows a stock‐adjustment principle towards the stochastic level that maximizes entrepreneurs' profits, I builds an inter‐temporal optimizing model in which the real wage is continuously set by an infinitely‐lived arbitrator called in to solve the dispute between workers and employers. This theoretical proposal verifies the natural presumption about real‐wage bargaining and suggests that unions are far from having a destabilizing role but, on the contrary, they may well speed up the adjustment to equilibrium. Moreover, I show that when unions do not care about unemployed workers, static bargaining models understate wage negotiation distortions. Copyright © 2010 John Wiley & Sons, Ltd.
Increase in the duration of antidepressant treatment from 1994 to 2003: a nationwide population‐based study from Finland
Authors: Sihvo Sinikka , Wahlbeck Kristian , McCallum Alison , Sevon Tiina , Arffman Martti , Haukka Jari , Keskimäki Ilmo , Hemminki Elina
Published: September 2010

Objective

We examined the length and continuity of antidepressant treatment and factors associated with long‐term of treatment among adults.

Methods

Nationwide data from all reimbursed antidepressant prescriptions in 1994–2003 were linked with patients' data retrieved from Statistics Finland and the Finnish Hospital Discharge Register. Logistic regression models were used to analyse long term use of antidepressants.

Results

The annual prevalence of antidepressant use increased from 3.6% in 1994 to 7.3% in 2003. Short‐term use (<3 months) decreased from 58% in 1995 to 51% in 2000 and long‐term treatment (≥12 months) increased from 18 to 21%. In 2000, 31% of treatment periods lasted ≥6 months and 24% ≥9 months. Long‐term treatment correlated to the purchase of other psychotropics, in‐patient psychiatric care, and prescription by a psychiatrist.

Conclusions

Treatment periods with antidepressants have become longer over time. Clinical factors related to mental disorder severity predict long‐term use. Only a quarter had the treatment duration recommended by clinical guidelines for depression. Copyright © 2010 John Wiley & Sons, Ltd.
Impact force of water jets in the hydroentanglement nonwoven process: Numerical simulation and experimental verification
Authors: Chen Ting , Wu Lili , Yang Xudong , Chen Ge
Published: September 2010

The water jet flow model in the hydroentanglement nonwoven process is established and solved numerically. The impact force of water jets is calculated with aid of the model and verified with the experimental data. The numerical simulation results of the impact force coincide with the experimental data, which confirms the effectiveness of the two‐dimensional model established. Computer simulations and experiments show that higher water jet pressure, smaller water jet inclination angle, and smaller standoff distance will yield larger impact force. The results show that there is great potential for this research in field of computer‐assisted design in hydroentanglement technology and equipment. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers.
Plastic deformation of low‐density polyethylene reinforced with biodegradable polylactide, Part 2: Creep characterization and modeling
Authors: Rezgui F. , G'Sell C. , Dahoun A. , Hiver J.M. , Sadoun T.
Published: September 2010

The behavior of low‐density polyethylene (LDPE) and two blends prepared with polylactide (PLA) was determined by means of a novel video‐controlled testing method under stretching at constant true strain rate, under creep at constant true stress, and under creep at constant nominal stress. Most tests were performed at 23°C and 50°C. In this second part, the experimental data are modeled with the G'Sell‐Jonas phenomenological law expressing the axial true stress versus axial true strain and axial true strain rate. This model describes correctly the various deformation stages: (i) initial viscoelasticity, (ii) plastic yielding, and (iii) strain hardening up to rupture. It shows clearly the reinforcing effect of the PLA particles that increases the yield stress in stretching experiments and slows down the deformation kinetics under creep. It is shown how the local stress/strain behavior is related to the standard force/extension curves. Consequently, it is proposed that tensile tests at constant true strain rates should be systematically preferred to creep tests for the characterization of constitutive relations because they take much less time to be performed. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers.
Dynamic friction property and mechanism of line‐type thermoplastic polymer materials for new optical wiring technology
Authors: Takeshita Yukitoshi , Handa Takao , Minami Hayato , Niwa Shinichi , Sugimoto Keiichiro
Published: September 2010

We have been developing a new optical wiring technology for installing indoor optical fiber cables directly into apartment houses for fiber to the home. The technology must minimize the friction of optical fiber cable. We reviewed many studies on friction behavior, and studied the friction properties of a wide variety of polymer sheets and optical fiber cables, and considered the friction mechanism. Relatively, soft polymer materials exhibited stick‐slip behavior and the hard polymers exhibited constant slip behavior. Lubricants are effective in reducing friction and play a dominant role as regards the friction property. Silicon and fluorocarbon agents play some role in converting the stick‐slip characteristic into constant slip behavior. A certain roughness is effective in reducing friction. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers.
Biochips that sequentially capture and focus antigens for immunoaffinity MALDI‐TOF MS: A new tool for biomarker verification
Authors: Brauer Heather Ann , Lampe Paul D. , Yasui Yutaka Y. , Hamajima Nobuyuki , Stolowitz Mark L.
Published: September 2010

A novel approach to immunoaffinity MS is described wherein antibodies are appended to a patterned gold Biochip surface. The Biochip surface is patterned with an array of concentric immunocapture zones composed of highly hydrophilic central zones surrounded by moderately hydrophilic zones that reside on a non‐wetting background, with protein attachment via electrochemically cleavable linkers. After linker cleavage, matrix application forms a discrete spot suitable for MALDI‐TOF‐MS. Use of the Biochip to purify transthyretin from human serum allowed a distinct resolution of four disulfide conjugates and one truncated form isoforms with good mass resolution and sensitivity.
On the Use of Composite Charges to Determine Insensitive Explosive Material Properties at the Laboratory Scale
Authors: Biss Matthew M. , Settles Gary S.
Published: September 2010

Laboratory‐scale air‐blast experiments an gram‐range composite explosive charges are presented. The composite charges consist of a spherical booster charge surrounded by a concentric, spherical “candidate material” shell charge. By way of composite charge explosive characterization, the candidate explosive material is able to be characterized through the “removal” of the known booster effects. Using peak shock wave pressures, a method is developed to remove the booster effects from the composite charge’s signature to yield the sole effects of the candidate explosive material, permitting its characterization. Air‐blast explosive tests are conducted using digital high‐speed shadowgraph visualization to measure the resulting shock wave radial position as a function of time. Booster and composite charge data are converted to Mach number versus shock wave radius profiles and subsequently to peak shock wave pressure versus shock wave radius profiles for characterization of the shell material. Explosives tested include: PETN, RDX, HMX, and Alliant Bullseye® SP.
Predicting memapsin 2 (β‐secretase) hydrolytic activity
Authors: Li Xiaoman , Bo Huang , Zhang Xuejun C. , Hartsuck Jean A. , Tang Jordan
Published: September 2010

Memapsin 2 (BACE1, β‐secretase), a membrane aspartic protease, functions in the cleavage of brain β‐amyloid precursor protein (APP) leading to the production of β‐amyloid. Because the excess level of β‐amyloid in the brain is a leading factor in Alzheimer's disease (AD), memapsin 2 is a major therapeutic target for inhibitor drugs. The substrate‐binding cleft of memapsin 2 accommodates 12 subsite residues, from P8 to P4′. We have determined the hydrolytic preference as relative kcat/KM (preference constant) in all 12 subsites and used these data to establish a predictive algorithm for substrate hydrolytic efficiency. Using the sequences from 12 reported memapsin 2 protein substrates, the predicted and experimentally determined preference constants have an excellent correlation coefficient of 0.97. The predictive model indicates that the hydrolytic preference of memapsin 2 is determined mainly by the interaction with six subsites (from P4 to P2′), a conclusion supported by the crystal structure B‐factors calculated for the various residues of transition‐state analogs bound to different memapsin 2 subsites. The algorithm also predicted that the replacement of the P3, P2, and P1 subsites of APP from Val, Lys, and Met, respectively, to Ile, Asp, and Phe, respectively, (APPIDF) would result in a highest hydrolytic rate for β‐amyloid‐generating APP variants. Because more β‐amyloid was produced from cells expressing APPIDF than those expressing APP with Swedish mutations, this designed APP variant may be useful in new memapsin 2 substrates or transgenic mice for AD studies.
Phenotypic effects of Ehlers–Danlos syndrome‐associated mutation on the FnIII domain of tenascin‐X
Authors: Zhuang Shulin , Linhananta Apichart , Li Hongbin
Published: September 2010

Tenascin‐X (TNX) is an extracellular matrix (ECM) protein and interacts with a wide variety of molecules in the ECM as well as on the membrane. Deficiency of TNX causes a recessive form of Ehlers–Danlos syndrome (EDS) characterized by hyperelastic and fragile skin, easy bruising, and hypermobile joints. Three point mutations in TNX gene were found to be associated with hypermobility type EDS and one of such mutations is the V1195M mutation at the 7th fibronectin Type III domain (TNXfn7). To help elucidate the underlying molecular mechanism connecting this mutation to EDS, here we combined homology modeling, chemical denaturation, single molecule atomic force microscopy, and molecular dynamics (MD) simulation techniques to investigate the phenotypic effects of V1195M on TNXfn7. We found that the V1195M mutation does not alter the three‐dimensional structure of TNXfn7 and had only mild destabilization effects on the thermodynamic and mechanical stability of TNXfn7. However, MD simulations revealed that the mutation V1195M significantly alters the flexibility of the C′E loop of TNXfn7. As loops play important roles in protein–protein and protein–ligand interactions, we hypothesize that the decreased loop flexibility by V1195M mutation may affect the binding of TNX to ECM molecules and thus adversely affect collagen deposition and fibrillogenesis. Our results may provide new insights in understanding the molecular basis for the pathogenesis of V1195M‐resulted EDS.
Modeling and predicting interactions between the human amphiphysin SH3 domains and their peptide ligands based on amino acid information
Authors: Cai Jianfeng , Ou Rongying , Xu Yun‐Sheng , Yang Li , Lin Zhihua , Shu Mao
Published: September 2010

In this paper, VHESH, which was a novel set of amino acid descriptors including hydrophobic, electronic, steric, and hydrogen bond contribution properties, were proposed to characterize the structures of the decapeptides binding the human amphiphysin‐1 Src homology 3 (SH3) domains, and QSAR model was constructed by partial least square (PLS) with genetic algorithm‐variable selection. It was found that diversified properties of the residues between P2 and P−3 (including P2 and P−3) of the decapeptide (P4P3P2P1P0P−1P−2P−3P−4P−5) may contribute remarkable effect to the interactions between the SH3 domain and decapeptides. Particularly, hydrogen bond and steric properties of P2 and electronic properties, steric properties of P−3 may provide relatively large positive contributions to the interactions. Based on the GA‐PLS model, a series of decapeptides, with relatively high binding affinities were designed. These results showed that VHESH descriptors can well represent the decapeptides. Furthermore, the model obtained, which showed low computational complexity, correlated VHESH descriptors with the binding affinities as well as that VHESH may also be applied in QSAR studies of peptides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Peptide hormone isoforms:N‐terminally branched PYY3–36 isoforms give improved lipid and fat‐cell metabolism in diet‐induced obese mice
Authors: Pedersen Søren L. , Sasikumar Pottayil G. , Chelur Shekar , Holst Birgitte , Artmann Andreas , Jensen Knud J. , Vrang Niels
Published: September 2010

The prevalence of obesity is increasing with an alarming rate worldwide and there is a need for efficacious satiety drugs. PYY3–36 has been shown to play a role in hypothalamic appetite regulation and novel analogs targeting the Y2 receptor have potential as drugs for the treatment of obesity. We have designed a series of novel PYY3–36 isoforms, by first adding the dipeptide Ile–LysN‐terminal to theNαof Ser‐13 in PYY13–36 and then anchoring theN‐terminal segment, e.g. PYY3–12, to the new LysNε‐amine. We hypothesized that such modifications would alter the folding of PYY, due to changes in the turn motif, which could change the binding mode to the Y receptor sub‐types and possibly also alter metabolic stability. In structure‐affinity/activity relationship experiments, one series of PYY isoforms displayed equipotency towards the Y receptors. However, an increased Y2 receptor potency for the second series of PYY isoforms resulted in enhanced Y receptor selectivity compared to PYY3–36. Additionally, acute as well as chronic mice studies showed body‐weight‐lowering effects for one of the PYY isoforms, which was also reflected in a reduction of circulating leptin levels. Interestingly, while the stability and pharmacokinetic profile of PYY3–36 and theN‐terminally modified PYY3–36 analogue were identical, only mice treated with the branched analogue showed marked increases in adiponectin levels as well as reductions in non‐esterified free fatty acids and triglycerides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Comparative Raman spectroscopy of individual and bundled double wall carbon nanotubes
Authors: Puech Pascal , Nanot Sébastien , Raquet Bertrand , Broto Jean‐Marc , Millot Marius , Anwar Abdul Waheed , Flahaut Emmanuel , Bacsa Wolfgang
Published: September 2010

Raman spectra of individual double wall carbon nanotubes(DWs) on silica show a splitting of the G band due to contributions of the inner and outer tube when using a excitation energy in resonance with the inner metallic tube and outer semiconducting tube. The spectral splitting indicates strong coupling while a previous report [Nanoletters 8, 3879 (2008)] shows uncoupled inner and outer tubes. The spectral line widths are comparable to what has been observed for individual single wall carbon nanotubes (SWs) or graphene. The spectral position of the inner tube is consistent with previous extrapolations from measurements under high pressure and on chemically doped double wall tubes. Bundling of DWs leads to heterogeneous increase of the G band line width. Increased laser power shifts the G band of the outer tube to higher energies and modifies its line shape.
Toward saturable absorbers for solid state lasers in form of holey fibers filled with single‐wall carbon nanotubes
Authors: Obraztsova E. D. , Tausenev A. V. , Chernov A. I.
Published: September 2010

Saturable absorbers in form of different media (liquids, polymers) with embedded single‐wall carbon nanotubes (SWNTs) already have shown their efficiency in formation of sub‐picosecond pulses in solid state lasers. One of the main limitations is a thermal degradation of such elements in a powerful laser beam. For fiber lasers the best solution would be to get a piece of fiber containing the distributed nanotubes in the core. Unfortunately the fiber treatment temperatures (exceeding 1000 °C in air) are destructive for carbon nanotubes. In this work, we demonstrate a saturable absorber formed via a room temperature filling of the holey fiber with an aqueous SWNT suspension, followed by drying. The evanescent field of the light propagating in the fiber interacts with the thin SWNT films deposited onto the walls of holes. The number of holes can be varied.

Thus, we have realized the all‐fiber SWNT saturable absorber. A mode locking regime with the sub‐picosecond output pulses has been realized with this absorber in Er fiber laser.

magnified image

A cross section of the holey fiber filled with single‐wall carbon nanotubes.
Characterization of group II hafnates and zirconates for metal–insulator–metal capacitors
Authors: Lupina Grzegorz , Seifarth Olaf , Dudek Piotr , Kozlowski Grzegorz , Dabrowski Jarek , Thieme Hans‐Jürgen , Lippert Gunther , Schroeder Thomas , Müssig Hans‐Joachim
Published: September 2010

Thin layers of SrHfO3, BaHfO3 and BaZrO3 are deposited onto TiN substrates and investigated in view of memory capacitor applications. The as deposited layers are amorphous and show dielectric constants of about 20. Rapid thermal annealing induces crystallization in the cubic perovskite phase and results in an increase of the dielectric constant up to 45. A combination of X‐ray absorption spectroscopy (XAS) and photoemission spectroscopy measurements reports high electronic band gap values comparable with that of reference HfO2 layers.
Surface ice observations on the St. Lawrence River using infrared thermography
Authors: Emond J. , Morse B. , Richard M. , Stander E. , Viau A. A.
Published: September 2010

Winter navigation requires regular and informative ice observations in order to provide safe and effective waterways. Acquiring field data is a costly, risky and difficult operation that can be greatly aided by airborne remote sensing. This paper reports on a field campaign designed to assess the utility of infrared thermography as a means of river ice monitoring. For this study, data were acquired on the St. Lawrence River. In March 2008, airborne infrared georeferenced images were acquired between Montreal and Quebec City, Canada. Following appropriate corrections and calibration, each image provided direct information on surface ice characteristics including superficial concentration and temperature. Ice floe thickness could also be deduced through the numerical analysis of ice surface temperature and near surface air temperature.

Taken as a whole, the set of images reveals phenomena and patterns in the observed ice floes. These include: surface median temperature (from −2 to 0°C); median thickness (from 1 to 3 cm); concentration (highly variable along successive reaches, varying from 0 to 100%); shape of floes (typically more oblong than circular); mean floe area (up to 5 ha) and number of floes per hectare (typically from 5 to 50). Along successive reaches, sectorial trends are observed for differing hydraulic conditions. Taken together, theses statistics bring out the variability inherent in the ice floes developed along the river, and lead to the conclusion that infrared thermography is a unique and effective tool for river ice monitoring, as it provides both rich visual and quantitative information. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of surface structural and mechanical changes following remineralization of dentin
Authors: Bertassoni Luiz Eduardo , Habelitz Stefan , Pugach Megan , Soares Paulo Cesar , Marshall Sally Jean , Marshall Grayson William
Published: September 2010

This study sought to gain insights into the surface structural and mechanical changes leading to remineralization of dentin. Remineralization was compared between a continuous remineralization approach and a nonbuffered static approach using solutions of the same initial composition. Artificial carious lesions were treated for 5 days and analyzed every 24 h using nanoindentation in water, SEM, and AFM. The continuous approach yielded a recovery of mechanical properties of up to 60% of normal dentin, whereas the static approach led to recovery of only 10%. Image analysis revealed that the static approach yielded the formation of areas suggestive of an apatite precipitate on the surface of the dentin matrix. In contrast, surface precipitate was absent using the continuous approach, suggesting that mineral formed within the lesion and re‐associated with the collagenous matrix. This study provided evidence that mechanical recovery of dentin in near physiological conditions is attainable through the continuous delivery of calcium and phosphate ions. SCANNING 32: 312–319, 2010. © 2010 Wiley Periodicals, Inc.
Small data set analysis in surface metrology: an investigation using a single point incremental forming case study
Authors: Powers B. M. , Ham M. , Wilkinson M. G.
Published: September 2010

A new method for applying statistical techniques with small data sets in surface metrology is demonstrated. This method allows for surfaces or surface‐creation processes to be differentiated with as few as six measurement regions. A case study in surface roughness of single point incremental forming is used to demonstrate this method because previous work in this area has not provided quantitative statistical testing to support conclusions. The results from the case study indicate that surface roughness parameters Sz and relative length at scales less than 200 nm are greater when the roll marks on the surface are oriented perpendicular rather than parallel to the forming direction. SCANNING 32: 199–211, 2010. © 2010 Wiley Periodicals, Inc.
Flash chemistry: flow microreactor synthesis based on high‐resolution reaction time control
Authors: Yoshida Jun‐Ichi
Published: September 2010

This article addresses a fascinating aspect of flash chemistry, high‐resolution reaction‐time control by virtue of a flow microreactor system, and its applications. The length of time that the solution remains inside the reactor is called the residence time. The residence time between the addition of a reagent and that of a quenching agent or the next reagent in a flow microreactor is the reaction time, and the reaction time can be greatly reduced by adjusting the length of a reaction channel in a flow microreactor. This feature is quite effective for conducting reactions involving short‐lived reactive intermediates. A reactive species can be generated and transferred to another location to be used in the next reaction before it decomposes by adjusting the residence time in the millisecond to second timescale. The principle of such high‐resolution reaction‐time control, which can be achieved only by flow microreactors, and its applications to synthetic reactions including Swern–Moffatt‐type oxidation, as well as the generation and reactions of aryllithium compounds bearing electrophilic substituents, such as alkoxycarbonyl groups, are presented. Integration of such reactions using integrated flow microreactor systems is also demonstrated. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 10: 332–341; 2010: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.201000020
Two decades of community‐based learning
Authors: Zlotkowski Edward , Duffy Donna
Published: September 2010

Community‐based learning is now more than a variation on community service. It is now a powerful pedagogy that can be used to enhance the common good. This pedagogy has proven itself to be an educational resource whose time has come.
The learning‐paradigm campus: From single‐ to double‐loop learning
Authors: Tagg John
Published: September 2010

Since the 1980s, advocates for change in higher education have called for double‐loop learning. One of the main criticisms of the evaluation of colleges and universities was that they measured inputs rather than the outputs. Higher education now needs to apply the lessons of learning and change to campus leadership and organization.
Student learning: From teacher‐directed to self‐regulation
Authors: Svinicki Marilla D.
Published: September 2010

This chapter discusses how far the field of Self‐Regulated Learning has come since the mid‐1990s based on the work started by Paul Pintrich. The growth in understanding of why self‐regulated learning is important to teaching and learning is outlined and Pintrich's model is presented and discussed.
Long‐term transportation, by road and air, of chub mackerel (Scomber japonicus) and atlantic bonito (Sarda sarda)
Authors: Correia João P.S. , Graça José T.C. , Hirofumi Morikawa , Kube Nicole
Published: September 2010

During the second semester of 2009, three trips were made from Olhão (Southern Portugal) to Stralsund (Northern Germany) carrying 2.122 animals, which included multiple teleosts, elasmobranchs and invertebrates. This group included scombrids, such as 1.869 Scomber japonicus and 9 Sarda sarda, which are notoriously difficult to transport. However, multiple adaptations to transport regimes adopted regularly have allowed the authors to successfully move these animals by road and air over a total of up to 25 hr. Such adaptations included maintaining oxygen saturation rates at approximately 200%, and also the constant addition of AmQuel®, sodium bicarbonate, and sodium carbonate. Different formulations were used during the three trips, with the best results corresponding to 20/30/30 ppm of the three aforementioned chemicals, respectively. The authors suggest, however, that a modified formula of 20/40/40 ppm will allow for an even more stable pH on future trips. Zoo Biol 30:459–472, 2010. © 2010 Wiley‐Liss, Inc.
Evaluation of two milk replacers fed to hand‐reared cheetah cubs (Acinonyx jubatus): nutrient composition, apparent total tract digestibility, and comparison to maternal cheetah milk
Authors: Bell Katherine M. , Rutherfurd Shane M. , Cottam Yvette H. , Hendriks Wouter H.
Published: September 2010

Commercially prepared milk replacers are frequently used to provide the sole source of nutrition for hand‐reared cheetah cubs (Acinonyx jubatus). The nutrient composition of two commonly used milk replacers was determined. Using titanium dioxide as an indigestible marker, nutrient digestibility was calculated from the analyses of fecal samples collected from each cub (n= 4 on formula 1, andn= 2 on formula 2). Mean apparent total tract digestibility for both formulas was >90% for all nutrients analyzed (crude protein, amino acids, crude fat (CF), and dry matter). However, the total CF content and the concentration of the essential fatty acids, such as α‐linolenic, linolenic, and arachidonic acid, of both formulas was lower than reported for maternal cheetah milk. Additionally, one formula contained a comparatively high amount of carbohydrate, at the expense of protein. Although data were lacking for cheetah maternal milk, comparison with domestic cat milk revealed high concentrations of a number of minerals (K, Fe, Zn, and Cu), while vitamin D3was not detected in one formula. Both formulas were low in the majority of essential amino acids compared with domestic cat maternal milk. Despite their apparently high digestibility, neither formula was complete or balanced in terms of nutrient concentrations and ratios when maternal cheetah milk and/or the requirements established for growth in domestic cats were used as estimates of ideal. On this basis, although all cubs in this study were healthy and maintained good body conditions for the duration of the trial, the results of dietary analyses indicate that these milk replacers may not provide optimal nutrition for growth in cheetah cubs when used for extended periods. Zoo Biol 30:412–426, 2011. © 2010 Wiley‐Liss, Inc.
Development of husbandry practices for the captive breeding of key largo woodrats (Neotoma floridana smalli)
Authors: Alligood Christina A. , Daneault Andre J. , Carlson Robert C. , Dillenbeck Thomas , Wheaton Catharine J. , Savage Anne
Published: September 2010

The Key Largo woodrat is an endangered rodent endemic to the island of Key Largo in the Florida Keys. After several reports documented a steep decline in the population, the US Fish and Wildlife Service developed a recovery plan, including captive breeding and reintroduction. Captive breeding efforts were to be focused on providing animals for future reintroduction to protected areas on Key Largo. However, little was known about the husbandry needs or reproductive behavior of this elusive nocturnal species. In 2005, Disney's Animal Kingdom® received 11 animals and began to systematically investigate methods of breeding Key Largo woodrats. Since the program's inception, 30 pups have been born and successfully parent reared. In this report, we describe some of the husbandry techniques that have contributed to the success of the Key Largo woodrat captive breeding program at Disney's Animal Kingdom®. The results obtained may be of use to other facilities maintaining woodrats and other rodent species. Zoo Biol 30:318–327, 2011.  © 2010 Wiley‐Liss, Inc.
Mucopolysaccharidosis type IIIB may predominantly present with an attenuated clinical phenotype
Authors: Valstar Marlies J. , Bruggenwirth Hennie T. , Olmer Renske , Wevers Ron A. , Verheijen Frans W. , Poorthuis Ben J. , Halley Dicky J. , Wijburg Frits A.
Published: September 2010

Mucopolysaccharidosis type IIIB (MPS IIIB, Sanfilippo syndrome type B) is a lysosomal storage disorder caused by deficiency of the enzyme N‐acetyl‐α‐D‐glucosaminidase (NAGLU). Information on the natural course of MPS IIIB is scarce but much needed in view of emerging therapies. To improve knowledge on the natural course, data on all 52 MPS IIIB patients ever identified by enzymatic studies in the Netherlands were gathered. Clinical data on 44 patients could be retrieved. Only a small number (n = 9; 21%) presented with a classical MPS III phenotype; all other patients showed a much more attenuated course of the disease characterized by a significantly slower regression of intellectual and motor abilities. The majority of patients lived well into adulthood. First signs of the disease, usually mild developmental delay, were observed at a median age of 4 years. Subsequently, patients showed a slowing and eventually a stagnation of development. Patients with the attenuated phenotype had a stable intellectual disability for many years. Molecular analysis was performed in 24 index patients. The missense changes p.R643C, p.S612G, p.E634K, and p.L497V were exclusively found in patients with the attenuated phenotype. MPS IIIB comprises a remarkably wide spectrum of disease severity, and an unselected cohort including all Dutch patients showed a large proportion (79%) with an attenuated phenotype. MPS IIIB must be considered in patients with a developmental delay, even in the absence of a progressive decline in intellectual abilities. A key feature, necessitating metabolic studies, is the coexistence of behavioral problems.
A new technique using metal tags to track small seeds over short distances
Authors: Canner Judith E. , Spence Meredith
Published: September 2010

Myrmecochory (seed dispersal by ants) is an evolutionarily and ecologically common mutualism. Since the first study of the phenomenon, ecologists have sought to develop techniques to track ant‐dispersed seeds. Often, thick leaf litter and the potential burial of seeds by ants make tracking of seeds difficult. Here we describe a seed‐tracking technique for small seeds, which uses magnetic tags, developed for mark–recapture studies of fish, to track seeds after dispersal into the ant nest in temperate deciduous forests. We discuss our use of the technique as well as suggestions for improvement and other possible applications of the technique.
A glycyl free radical as the precursor in the synthesis of carbon monoxide and cyanide by the [FeFe]‐hydrogenase maturase HydG
Authors: Nicolet Yvain , Martin Lydie , Tron Cécile , Fontecilla-Camps Juan C.
Published: September 2010

HydG uses tyrosine to synthesize the CN−/CO ligands of [FeFe]‐hydrogenase active site. We have mutated two of the [4Fe–4S]‐cluster cysteine ligands of the HydG C‐terminal domain (CTD) to serine. The double mutant can still synthesize CN− but not CO. In a mutant lacking the CTD both CN− and CO synthesis are abolished. Like in ThiH, the initial steps of CN− synthesis are carried out in the TIM‐barrel domain of HydG but some component(s) of the CTD are later needed. The mutants indicate that CO synthesis is metal‐based and occurs in the CTD. We postulate that CN−/CO synthesis is initiated by H2N–CH–urn:x-wiley:00145793:media:feb2s0014579310007283:feb2s0014579310007283-math-si1 Fragmentation of this radical into H2N–CH2 and CO2 or H2CNH and provides plausible precursors for CN−/CO synthesis.
Coevolution is a short‐distance force at the protein interaction level and correlates with the modular organization of protein networks
Authors: Liang Zhi , Xu Meng , Teng Maikun , Niu Liwen , Wu Jiarui
Published: September 2010

We investigated what roles coevolution plays in shaping yeast protein interaction network (PIN). We found that the extent of coevolution between two proteins decreases rapidly as their interacting distance on the PIN increases, suggesting coevolutionary constraint is a short‐distance force at the molecular level. We also found that protein–protein interactions (PPIs) with strong coevolution tend to be enriched in interconnected clusters, whereas PPIs with weak coevolution are more frequently present at inter‐cluster region. The findings indicate the close relationship between coevolution and modular organization of PINs, and may provide insights into evolution and modularity of cellular networks.
Solution structure of the N‐terminal catalytic domain of human H‐REV107 – A novel circular permutated NlpC/P60 domain
Authors: Ren Xiaobai , Lin Jian , Jin Changwen , Xia Bin
Published: September 2010

H‐REV107 is a Ca2+‐independent phospholipase A1/2, and it is also a pro‐apoptosis protein belonging to the novel class II tumor suppressor family, H‐REV107‐like family. Here we report the solution structure of the N‐terminal catalytic domain of human H‐REV107, which has a similar architecture to classical NlpC/P60 domains, even though their fold topologies are different due to circular permutation in the primary sequence. The phospholipase active site possesses a structurally conserved Cys–His–His catalytic triad as found in NlpC/P60 peptidases, indicating H‐REV107 should adopt a similar catalytic mechanism towards phospholipid substrates to that of NlpC/P60 peptidases towards peptides. As H‐REV107 is highly similar to lecithin retinol acyltransferase, our study also provides structural insight to this essential enzyme in retinol metabolism.
Overexpression of SCYL1‐BP1 stabilizes functional p53 by suppressing MDM2‐mediated ubiquitination
Authors: Yan Jing , Di Yujun , Shi Huili , Rao Hai , Huo Keke
Published: September 2010

Previously, we defined SCY1‐like 1 binding protein 1 (SCYL1‐BP1) to be a substrate of Pirh2 that binds to mouse double minute gene number 2 (MDM2). In the current study, we found that an increase in SCYL1‐BP1 protein levels caused a parallel change in the amount of p53 protein due to the inhibition by SCYL‐BP1 of MDM2‐mediated p53 ubiquitination. SCYL1‐BP1 was not able to alter the ubiquitination of p53 by human papillomavirus protein E6, indicating that the effect was specific for MDM2. Increases in the level of SCYL1‐BP1 protein in cells led to the greater transcriptional activation of p21 and gadd45, reduced rate of cellular proliferation, increased levels of apoptosis and inhibition of tumorigenicity. Thus, we propose that SCYL1‐BP1 is a novel regulator of the MDM2‐p53 feedback loop and that it may be a potential tumor suppressor.
Fullness and Dearth: Depth Experience and Democratic Life
Authors: WHITE STEPHEN K.
Published: September 2010

How should inquiry into ethical-political life come to terms with “depth experience?” By this, I mean extraordinary experience that breaks into the familiar frames of meaning and reasoning that undergird everyday life, bringing some sort of transformation or significant solidification of basic commitments or identity. Stated in this abstract fashion, my question is likely to seem rather bewildering or uninteresting for the study of politics. But its potential significance becomes apparent if one mentions George W. Bush and being “born again.” This article speculates more broadly about such experience, expanding the focus beyond theists and “limit” experiences. When one does this, depth experience need not be thought of as anathema to political theory. Rather, I show that it can be cultivated in such a way as to animate an admirable “bearing” on the part of citizens of affluent, late-modern societies and cohere with certain fundamentals of deliberative democracy.
DOES POSSESSION OF ASSETS INCREASE WOMEN'S PARTICIPATION IN REPRODUCTIVE DECISION-MAKING? PERCEPTIONS OF NIGERIAN WOMEN
Authors: OMEJE JOACHIM C. , OSHI SARAH N. , OSHI DANIEL C.
Published: September 2010

This study is based on a population-based, descriptive questionnaire survey, the objective of which was to elicit the perceptions of women in south-eastern Nigeria on whether possession of economic/household assets by women enhanced their capacity to negotiate reproductive issues with their husbands. The findings show that the respondents believed that possession of economic/household assets by women in their communities might not necessarily increase their negotiation power in their reproductive decision-making. Other factors tend to attenuate the effects of women's possession of economic/household assets on their reproductive bargaining power. Notable among these may be social norms that implicitly arrogate control of the assets owned by the conjugal couple to the man, even when they are bought by the women. Planners of reproductive health intervention projects, policy-makers and researchers need to be aware of such sociocultural specific phenomena, which do not fit with widely held international beliefs.
Why Do Firms with Diversification Discounts Have Higher Expected Returns?
Authors: Mitton Todd , Vorkink Keith
Published: September 2010

A diversified firm can trade at a discount to a matched portfolio of single-segment firms if the diversified firm has either lower expected cash flows or higher expected returns than the single-segment firms. We study whether firms with diversification discounts have higher expected returns in order to compensate investors for offering less upside potential (or skewness exposure) than focused firms. Our empirical tests support this hypothesis. First, we find that focused firms offer greater skewness exposure than diversified firms. Second, we find that diversified firms have significantly larger discounts when the diversified firm offers less skewness than matched single-segment firms. Finally, we find that up to 53% of the excess returns received on diversification-discount firms relative to diversification-premium firms can be explained by differences in exposure to skewness.
Information Quality and Stock Returns Revisited
Authors: Brevik Frode , d’Addona Stefano
Published: September 2010

This paper investigates the relation between information on the state of the economy and equity risk premium. We use a setup where investors have Epstein-Zin preferences and the economy randomly switches between booms and recessions. We are able to establish 2 key results: First, investors with high elasticity of intertemporal substitution (EIS) will require lower excess returns for holding stocks if they are provided with better information on the state of the economy. Second, we find that this also holds for investors with moderate EIS if they are sufficiently risk averse.