bluuebunny/crossref_metadata_2025_split huggingface dataset:
A fault detection and isolation filter design method for Markov jump linear parameter‐varying systems
Authors: Gagliardi Gianfranco , Casavola Alessandro , Famularo Domenico 
Published: June 2011

SUMMARYA fault detection and isolation (FDI) filter design method is proposed for linear parameter‐varying (LPV) systems, which are subject to abrupt changes in their structure. Such a phenomenon is modeled by a finite state Markov chain whose outcome is supposed to be directly available along with its rates transition matrix. The FDI filter is designed as a bank of ℋ︁−/ℋ︁∞ Luenberger observers, derived by optimizing frequency conditions that ensure guaranteed levels of disturbance rejection, fault sensitivity and are capable to discriminate anomalous events belonging to different fault classes. It is proved that, by resorting to stochastic stability concepts, the design method can be recast as a linear matrix inequality programming program in the observer bank gains. The resulting residual generator is a jump parameter‐dependent observer jointly exploiting the available measures on the deterministic plant parameter and on the instantaneous Markov chain realization. An FDI threshold logic is also proposed in order to reduce the generation of false alarms. The effectiveness of the design technique is illustrated via a numerical example. Copyright © 2011 John Wiley & Sons, Ltd.
Dietary effects on development of the human mandibular corpus
Authors: Holmes Megan A. , Ruff Christopher B. 
Published: June 2011

AbstractThe extent to which the mandibular corpus exhibits developmental plasticity has important implications for interpreting variation in adult and juvenile mandibular morphology in the archaeological and paleontological record. Here, we examine ontogenetic changes in mandibular corpus breadth, rigidity, and strength in two population samples with contrasting diets: late prehistoric Tigara from Point Hope, Alaska, characterized by a very demanding masticatory regime, and proto‐historic Arikara from the Sully Site in South Dakota, with a less demanding regime. A total of 52 juvenile and 11 adult Tigara, and 32 juvenile and 10 adult Arikara were included in the study. Juveniles ranged in age from 1 to 17 years, with good representation of younger (1–6‐year‐old) juveniles (20 Arikara, 18 Tigara). Superoinferior and buccolingual external and cortical bone breadths of mandibles were measured at the Pm4‐M1 and M1‐M2 junctions using calipers and biplanar radiographs, respectively. An asymmetrical hollow beam model was employed to reconstruct cross sections and calculate bending rigidities and strengths in the sagittal and transverse planes. Among adults, Tigara have greater transverse corpus width, bending rigidity, and strength, and ratios of transverse to sagittal dimensions than Arikara. This shape difference develops gradually during growth, with only weak trends among young juveniles, increasing to near‐adult contrasts among adolescents. These results support a role for functional mechanical loading of the mandible during growth in producing adult differences in mandibular corpus morphology. Am J Phys Anthropol 2011. © 2011 Wiley‐Liss, Inc.
Effect of chemical modification of oil fly ash and compatibilization on the rheological and morphological properties of low‐density polyethylene composites
Authors: Khan Muhammad J. , Al‐Juhani Abdulhadi A. , Ul‐Hamid Anwar , Shawabkeh Reyad , Hussein Ibnelwaleed A. 
Published: June 2011

AbstractIn this study, the effect of oil fly ash (OFA), a by‐product of oil fuel power plants, on the rheological and morphological behavior of low‐density polyethylene (LDPE) is investigated. As received and acid‐functionalized OFA (COOH‐OFA) are used to examine the effect of surface modification of OFA on polymer–filler composites. LDPE/OFA composites were prepared by melt mixing with filler loading in the range 1–10 wt %. The results are compared with pure LDPE. The effect of polyethylene‐grafted‐maleic anhydride (PE‐g‐MA) as a compatibilizer was also studied. Both viscous and elastic properties of composites increased with OFA loading especially at low frequency. The surface modification of OFA has influenced the properties of OFA. As‐received OFA showed some agglomeration at high loading that resulted in two‐phase system as described by scanning electron microscopy (SEM) and Cole–Cole plot. Field emission‐SEM (FE‐SEM) images showed improvement in the dispersion of COOH‐LDPE/OFA composites. In addition, the surface modification reduced the size of agglomeration. In general, the COOH modification of OFA improved both the dispersion and rheological properties of OFA. With chemical modification, the concentration of the filler can be increased to 10% without compromising the properties of the composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Mutually reinforced multicomponent polysaccharide networks
Authors: Hyland Laura L. , Taraban Marc B. , Hammouda Boualem , Bruce Yu Y. 
Published: June 2011

AbstractNetworks made from chitosan and alginate have been utilized as prospective tissue engineering scaffolds due to material biocompatibility and degradability. Calcium (Ca2+) is often added to these networks as a modifier for mechanical strength enhancement. In this work, we examined changes in the bulk material properties of different concentrations of chitosan/alginate mixtures (2, 3, or 5% w/w) upon adding another modifier, chondroitin. We further examined how material properties depend on the order the modifiers, Ca2+ and chondroitin, were added. It was found that the addition of chondroitin significantly increased the mechanical strength of chitosan/alginate networks. Highest elastic moduli were obtained from samples made with mass fractions of 5% chitosan and alginate, modified by chondroitin first and then Ca2+. The elastic moduli in dry and hydrated states were (4.41 ± 0.52) MPa and (0.11 ± 0.01) MPa, respectively. Network porosity and density were slightly dependent on total polysaccharide concentration. Average pore size was slightly larger in samples modified by Ca2+ first and then chondroitin and in samples made with 3% starting mass fractions. Here, small‐angle neutron scattering (SANS) was utilized to examine mesh size of the fibrous networks, mass‐fractal parameters and average dimensions of the fiber cross‐sections prior to freeze‐drying. These studies revealed that addition of Ca2+ and chondroitin modifiers increased fiber compactness and thickness, respectively. Together these findings are consistent with improved network mechanical properties of the freeze‐dried materials. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 840–851, 2011.
Diverse role of conformational dynamics in carboxypeptidase A‐driven peptide and ester hydrolyses: Disclosing the “Perfect Induced Fit” and “Protein Local Unfolding” pathways by altering protein stability
Authors: Shushanyan Mikhael , Khoshtariya Dimitri E. , Tretyakova Tatyana , Makharadze Maya , van Eldik Rudi 
Published: June 2011

AbstractCatalytic mechanisms of carboxypeptidase A (CPA) are well known for their diversity and the relative inaccessibility for a decisive comprehension. Recent encouraging attempts through modern computational techniques promoted new challenges for the complementary experimental endeavors. In this work, we have applied the stopped‐flow technique and the method of reaction progress curve fitting to extract kinetic parameters for the CPA‐catalyzed hydrolyses of smaller (typical) peptide and ester substrates, known for their strong activating/inhibiting impact, thus to which the traditional method of “initial rates” is not applicable. Our approach that innately implies the overall constancy of the affecter (substrate plus “active” product) concentration, made it possible to rigorously determine the physically meaningful “effective” values for the catalytic and Michaelis constants under diverse experimental conditions including variable temperature and urea or trimethylamine N‐oxide concentrations. Analysis of the obtained results allowed for: (i) the further substantiation of diverse mechanistic patterns for archetypal specific peptide and ester substrates, (ii) testing and disclosure of intrinsic links between the stabilizing/destabilizing and activating/inhibiting effects for the important model enzyme, CPA, and (iii) tentative explanation of a distinct activating/inhibiting impact of these substrates through the strong specific interaction of their benzyl (Bz) moiety with the substrate binding S3 subsite of CPA. We have demonstrated that stabilization of CPA either through the interaction with an extra Bz moiety (belonging to another substrate or to the product) leads to the increase of its catalytic power with respect to the specific peptide substrate and to its decrease with respect to the counterpart ester substrate. We conjecture that the catalytic mechanisms operating in these two cases include: (a) the “promoted water” mechanism for the peptide substrate that, seemingly, provides the almost “perfect induced fit” (low‐barrier conformational adaptation), and (b) presumably, the “anhydride intermediate” mechanism for the ester substrate that, anyway, requires substantial conformational rearrangement (in fact, “partial or local unfolding”) of the protein environment in the course of the rate‐determining step. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 852–870, 2011.
Practical implications of implementing a unit record system on a community college campus
Authors: Offermann Joe , Smith Ryan 
Published: June 2011

AbstractLittle attention has been paid to the practical implications of implementing a unit record system on a community college campus. Potential benefits include the ability to capture student success and track outcomes for external compliance and internal planning efforts, but potential issues could impact the ability of a community college to manage the implementation of a system, including privacy, security, dealing with students who opt out, integration with current systems, data verification, and agency coordination. This chapter addresses the challenges and opportunities of implementing a unit record system on campus by addressing potential costs, benefits, and integration with already existing data and accountability processes.
What is next? Futuristic thinking for community colleges
Authors: Ramage Thomas 
Published: June 2011

AbstractToday's society is marked by massive political, social, and scientific transformations on a daily basis. However, these transformations are rarely discussed in the context of what it means to be an educated person. Our efforts to forecast, even for periods as little as five or ten years out, have been predicated on the assumption that the current rate of progress will continue into the future. A brief analysis of data—at all scales and scopes, in different time scales, and for a wide variety of technologies ranging from the electronic to the biological—illustrates that our notion of static rates of change is incorrect: Change, progress, and advancement are all happening at an accelerating rate. This chapter provides a presidential perspective on these trends to suggest that students of tomorrow must be educated in very different ways our institutions must adapt to be ready.
Redispersion Microreactor System for Phase Transfer Catalyzed Esterification
Authors: Jovanović Jovan , Hengeveld Wessel , Rebrov Evgeny V. , Nijhuis Tjeerd A. , Hessel Volker , Schouten Jaap C. 
Published: June 2011

AbstractEin Interdigital‐Mikromischer/Redispergierkapillare‐Aufbau soll die in anderen Mikroreaktoren übliche Tropfenkoaleszenz für Flüssig/Flüssig‐Strömungen verhindern oder minimieren. Die Redispergierkapillare beinhaltet 1 mm lange Einschnürungen mit 0,25 mm innerem Durchmesser, die jeweils in Abständen von 0,5 m entlang der Kanallänge positioniert werden. Die Leistungsfähigkeit dieses Systems wurde anhand der phasentransferkatalysierten Veresterung zu Benzylbenzoat getestet. Mithilfe der Einschnürungen konnte die Koaleszenz verhindert werden, was zu einer besseren Reproduzierbarkeit der Versuchsergebnisse führte. Durch die Einstellung der Gesamtflussrate und des Verhältnisses von wässriger zu organischer Phase wurden Oberflächen/Volumen‐Verhältnisse von bis zu 230 700 m2m–3 erreicht. Im Vergleich zur konventionellen phasentransferkatalysierten Veresterung konnten durch den Konti‐Betrieb im Interdigital‐Mikromischer/Redispergierkapillare‐Aufbau das Lösungsmittel, der Basenzusatz sowie ein energieintensiver Destillationsschritt eliminiert werden, während die Prozesssicherheit erhöht wurde.
Multiscale Description of Mass Transfer Processes for Gas‐Liquid Reactions
Authors: Kück Ulf D. , Kröger Michael , Bothe Dieter , Räbiger N. , Schlüter Michael , Warnecke Hans‐Joachim 
Published: June 2011

AbstractDer skalenübergreifende Stofftransport an frei aufsteigenden, kugelförmigen Gasblasen mit überlagerter chemischer Reaktion wird untersucht. Dazu wird der aus numerischen Simulationen und experimentellen Untersuchungen berechnete Sauerstoff‐Stofftransport ohne chemische Reaktion quantitativ verglichen und der Einfluss der Sulfit/Sulfat‐Reaktion auf das Konzentrationsfeld qualitativ gezeigt. Die numerischen Simulationen liefern detaillierte Informationen über das Geschwindigkeitsfeld während die Experimente eine hochaufgelöste Analyse des Konzentrationsfeldes erlauben. Die Ergebnisse zu Strömungs‐ und Konzentrationsfeldern aus Simulationen und Experimenten werden gegenseitig validiert und so kombiniert, dass ein ausreichend hoher Detaillierungsgrad für die Berechnung von lokalen Sauerstoffmassenströmen erreicht wird.
Etude de l'élimination des ions Cu (II) de la solution aqueuse par sorption sur la zéolithe a study of the removal of Cu (II) from aqueous solution by sorption on Zeolite A
Authors: Rida Kamel , Goutas Warda , Medjetena Imane 
Published: June 2011

AbstractL'objectif de cette étude est de présenter les résultats d'élimination du cuivre par le procédé de sorption sur la zéolithe A. Les expériences en batch ont été effectuées aussi bien pour les cinétiques que pour les isothermes de sorption. Les variables expérimentales étudiées étaient le pH, le temps de contact à différentes concentrations initiales, la quantité de sorbant, la température et la vitesse d'agitation. La capacité de sorption dépend du pH et de la masse de sorbant, alors que la température et la vitesse d'agitation ne montrent aucune influence. Plusieurs mécanismes de rétention du cuivre sur la zéolithe pourraient être compétitifs (échange d'ions, complexation ou précipitation et sorption). La modélisation des données expérimentales relatives aux cinétiques a montré que le modèle de pseudo‐second ordre décrit d'une façon satisfaisante la sorption sur la zéolithe, et que l'étape limitante de la vitesse est la diffusion intraparticule. L'analyse statistique des constantes relatives a l'équation de Langmuir‐Freundlich a montré que ce modèle semble être le plus approprié pour décrire le présent phénomène de sorption, ce qui indique l'hétérogénéité de la surface de sorption de la zéolithe. © 2011 Canadian Society for Chemical Engineering
Toward the Discovery of Novel Anti‐HIV Drugs. Second‐Generation Inhibitors of the Cellular ATPase DDX3 with Improved Anti‐HIV Activity: Synthesis, Structure–Activity Relationship Analysis, Cytotoxicity Studies, and Target Validation
Authors: Maga Giovanni , Falchi Federico , Radi Marco , Botta Lorenzo , Casaluce Gianni , Bernardini Martina , Irannejad Hamid , Manetti Fabrizio , Garbelli Anna , Samuele Alberta , Zanoli Samantha , Esté José A. , Gonzalez Emmanuel , Zucca Elisa , Paolucci Stefania , Baldanti Fausto , De Rijck Jan , Debyser Zeger , Botta Maurizio 
Published: June 2011

AbstractA hit optimization protocol applied to the first nonnucleoside inhibitor of the ATPase activity of human DEAD‐box RNA helicase DDX3 led to the design and synthesis of second‐generation rhodanine derivatives with better inhibitory activity toward cellular DDX3 and HIV‐1 replication. Additional DDX3 inhibitors were identified among triazine compounds. Biological data were rationalized in terms of structure–activity relationships and docking simulations. Antiviral activity and cytotoxicity of selected DDX3 inhibitors are reported and discussed. A thorough analysis confirmed human DDX3 as a valid anti‐HIV target. The compounds described herein represent a significant advance in the pursuit of novel drugs that target HIV‐1 host cofactors.
Cell‐type‐specific consequences of reelin deficiency in the mouse neocortex, hippocampus, and amygdala
Authors: Boyle Maureen P. , Bernard Amy , Thompson Carol L. , Ng Lydia , Boe Andrew , Mortrud Marty , Hawrylycz Michael J. , Jones Allan R. , Hevner Robert F. , Lein Ed S. 
Published: June 2011

AbstractStrict segregation of layerspecific molecular markers in adult mouse somatosensory cortex. Pseudocolored overlay of serial brain sections labeled using fluorescent in situ hybridization for layer‐specific cortical markers Ctgf (layer 6b, purple), TC1460681 (Igh6, layer 6, green), Etv1 (layer 5, yellow), Rorb (layer 4, red), and Rgs8 (layer 2/3, light blue). The Journal of Comparative Neurology, Volume 519, Number 11, pages 2061–2089.
Structural and Size Effects on the Spectroscopic and Redox Properties of CdSe Nanocrystals in Solution: The Role of Defect States
Authors: Amelia Matteo , Impellizzeri Stefania , Monaco Simone , Yildiz Ibrahim , Silvi Serena , Raymo Françisco M. , Credi Alberto 
Published: June 2011

AbstractTwo series of CdSe quantum dots (QDs) with different diameters are prepared, according to frequently used protocols of the same synthetic procedure. For each sample the photophysical properties and the potentials for the first reduction and oxidation processes in organic solution are determined. The band gap obtained from electrochemical experiments is compared with that determined from the absorption and luminescence spectra. While the optical band gap decreases upon increasing the nanocrystal diameter, as expected on the basis of quantum confinement, the redox potentials and the electrochemical band gap are not monotonously related to the QD size. For both series, the smallest and largest QDs are both easier to oxidize and reduce than mid‐sized QDs. In fact, the latter samples exhibit very broad voltammetric profiles, which suggests that the heterogeneous electron‐transfer processes from/to the electrode are kinetically hindered. Conversely, the electrochemical band gap for the smallest and largest particles of each series is somewhat smaller than the optical band gap. These results indicate that, while the optical band gap depends on the actual electron–hole recombination within the nanocrystal, and therefore follows the size dependence expected from the particle‐in‐a‐box model, the electrochemical processes of these QDs are strongly affected by other factors, such as the presence of surface defects. The investigations suggest that the influence of these defects on the potential values is more important for the smallest and largest QDs of each series, as confirmed by the respective luminescence bands and quantum yields. An interpretation for the size‐dependent evolution of the surface defects in these nanocrystals is proposed based on the mechanism of their formation and growth.
Multisensing Emissive Pyrimidine
Authors: Sinkeldam Renatus W. , Marcus Paul , Uchenik Dmitriy , Tor Yitzhak 
Published: June 2011

AbstractFluorescent nucleoside analogs, commonly used to explore nucleic acid dynamics, recognition and damage, frequently respond to a single environmental parameter. Herein we address the development of chromophores that can simultaneously probe more than one environmental factor while having each associated with a unique spectroscopic signature. We demonstrate that an isomorphic emissive pyridine‐modified 2‐deoxy‐uridine 1, containing multiple sensory elements, responds to changes in acidity, viscosity, and polarity. Protonation of the pyridine moiety (pKa 4.4) leads to enhanced emission (λem=388 nm) and red‐shifted absorption spectra (λabs=319 nm), suggesting the formation of an intramolecular hydrogen bond with the neighboring pyrimidine carbonyl. This “locked” conformation can also be mimicked by increasing solvent viscosity, resulting in a stark enhancement of emission quantum yield. Finally, increasing solvent polarity substantially impacts the chromophore’s Stokes shift [from 5.8×103 cm−1 at ET(30)=36.4 kcal mol−1 to 9.3 ×103 cm−1 at ET(30)=63.1 kcal mol−1]. The opposite effect is seen for the impact of solvent polarity of the protonated form. The characteristic photophysical signature induced by each parameter facilitates the exploration of these environmental factors both individually and simultaneously.
Initial spectrum access control with QoS protection for active users in cognitive wireless networks
Authors: Zhang Jianmin , Zhang Zhaoyang , Luo Haiyan , Wang Wei , Yu Guanding 
Published: June 2011

SUMMARYIn this paper, an initial spectrum access control algorithm for cognitive wireless networks was studied. The objective was to maximize the number of admitted secondary users (SUs) under the constraints of interference temperature at multiple measurement points (MPs), while providing active SUs' QoS protection (AQP). Here, AQP means that the signal‐to‐interference‐plus‐noise ratios (SINRs) of all active SUs will not fluctuate below some predefined thresholds during a new SU's initial spectrum access process. To this end, we proposed a new distributive power control algorithm in conjunction with a simple alarm mechanism that ensures the interference temperatures at multiple MPs to be always below their thresholds during the initial spectrum access process. Then, two realizations of the spectrum access algorithms, namely, D‐AQP and C‐AQP, according to whether the MPs can act as local controllers or not, were presented. In the D‐AQP algorithm, each SU updates its transmit power distributively based on the local information including the current SINR, the QoS requirement, and the indicator from the MPs so that the resultant SINRs of the active SUs are able to stay above the predefined thresholds. Whereas in the C‐AQP algorithm, apart from the same procedure as mentioned, each MP is supposed to be able to decide which new SU should quit the initial spectrum access process so as to protect the communication quality of the primary system. Finally, the performances of the proposed algorithms were validated by extensive simulations. Copyright © 2011 John Wiley & Sons, Ltd.
Small fibre neuropathy: role in the diagnosis of diabetic sensorimotor polyneuropathy
Authors: Malik R. A. , Veves A. , Tesfaye S. , Smith G. , Cameron N. , Zochodne D. , Lauria G. ,   on behalf of The Toronto Consensus Panel on Diabetic Neuropathy
Published: June 2011

AbstractSmall fibres constitute 70–90% of peripheral nerve fibres and regulate several key functions such as tissue blood flow, temperature and pain perception as well as sweating, all of which are highly relevant to the clinical presentation and adverse outcomes associated with foot ulcerations in patients with diabetes. Recent studies demonstrated significant abnormalities in the small fibres in subjects with impaired glucose tolerance and diabetes, despite normal electrophysiology, suggesting that the earliest nerve fibre damage is to the small fibres. Unfortunately, guidelines and consensus statements focus on large fibres and continue to advocate electrophysiology as a diagnostic modality and as a primary end point for the assessment of therapeutic benefit. (In part, this reflects the difficulties in quantifying small fibre dysfunction and damage.) We have therefore critically assessed currently available techniques that measure small fibre dysfunction in diabetic neuropathy, using quantitative sensory and sudomotor testing. We have assessed the role of identifying structural damage by quantifying intraepidermal nerve fibre density in skin biopsies and corneal nerve morphology using corneal confocal microscopy. Finally, we propose a definition for diabetic neuropathy that incorporates small fibre damage. Copyright © 2011 John Wiley & Sons, Ltd.