bluuebunny/crossref_metadata_2025 huggingface dataset:
Resources for Preparing Middle School Mathematics Teachers
Authors: Krantz Steven G.
Published: May 2013

Middle school mathematics teachers occupy a unique place in the mathematical development of students. These teachers need to be proficient in all elementary mathematics topics, together with some secondary mathematics topics. They demand a special kind of preparation that differs from both that of their elementary and secondary colleagues. The Mathematics Education of Teachers (MET) document published by the Conference Board of the Mathematical Sciences set forth criteria for the preparation of mathematics middle school teachers which made it critical that special programs and courses for this group emerge. This collection of articles is in response to the MET document and the result of several gatherings of mathematics educators and mathematicians training middle school teachers. We have chosen the articles that appear in this volume for several purposes: to disseminate various middle school programs structures, to detail methods of teaching specific middle school teachers content courses, and to share materials and resources. While each article describes the unique program or course of its respective institution, each also includes a common core of information to provide some consistency to the volume. In particular, all articles describing middle school programs contain information about the host institution, a history of the program, degree and testing requirements for the program and for state licensure, learning goals and objectives for the program and courses, and any available assessment data. When applicable information is included about particular courses, for example, some articles provide sample activities or syllabi and some have a description of courses in the appendix. Most articles have links to websites containing further information about the program, courses, state requirements, or resources that can be downloaded and used directly.
A First Course in Functional Analysis
Authors: Sen Rabindranath
Published: May 2013

This book provides the reader with a comprehensive introduction to functional analysis. Topics include normed linear and Hilbert spaces, the Hahn-Banach theorem, the closed graph theorem, the open mapping theorem, linear operator theory, the spectral theory, and a brief introduction to the Lebesgue measure. The book explains the motivation for the development of these theories, and applications that illustrate the theories in action. Applications in optimal control theory, variational problems, wavelet analysis and dynamical systems are also highlighted. A First Course in Functional Analysis will serve as a ready reference to students not only of mathematics, but also of allied subjects in applied mathematics, physics, statistics and engineering.
The Mahatma Misunderstood
Authors: Shingavi Snehal
Published: May 2013

The Mahatma Misunderstood is a study of the fiction about Gandhi produced in his lifetime, and explains why novelists both vehemently critiqued and lovingly collaborated with the Mahatma simultaneously.
Mechanism of action of differentd‐spacings clays on the intumescent fire retardance of polymers
Authors: da Silva Ribeiro Simone Pereira , de Moura Estevão Luciana Rocha , Pereira Celeste Margarida Correia , Nascimento Regina Sandra Veiga
Published: May 2013

Aseries of sodic and organophilic clays with differentd‐spacings was added to a polymeric matrix of poly (ethylene‐co‐butyl acrylate) EBA‐30, containing an intumescent formulation of ammonium polyphosphate (APP) and pentaerythritol (PER), in order to investigate the influence of thed‐spacings of the clays on their synergistic effects with the intumescent formulation. A series of samples was evaluated through cone calorimetry, SEM, TG‐FTIR, FTIR, and XRD of burned residues. The results revealed that the addition of clays with smallerd‐spacings led to a synergistic interaction with the intumescent formulation, and consequently to an improvement in the flame retardance of the materials. This effect was not observed with the addition of clays withd‐spacings larger than 30 Å. For these materials, the formation of a less homogeneous and structured intumescent layer, and a delay in the formation of the phosphocarbonaceous species which act as char precursors was observed. This delay could be responsible for the loss of synergy and also for the type of char morphology formed when largerd‐spacings clays were used. XRD analyses results indicated that the presence of clays in the materials promoted changes in the crystalline phase of the char when the samples were submitted to higher temperatures. Those changes probably allowed for the maintenance of the structures at high temperatures. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1759–1771, 2013
Barrier and mechanical properties of biodegradable poly(ε‐caprolactone)/cellophane multilayer film
Authors: Shi Cancan , Zhang Shuhong , Li Mengting , Sun Wenxiu , Fan Guisheng , Jin Ye , Yang Jinjun , Dong Tungalag
Published: May 2013

In this study, cellophane (PT) multilayer films were prepared by coating with different thickness of poly(ε‐caprolactone) (PCL) and chitosan (CH), and its effects on barrier and mechanical properties were evaluated. It was shown that the PCL/PT/PCL and PCL/CH/PT/CH/PCL multilayer films exhibit much better water vapor barrier than PT, and these films still keep the high oxygen barrier. And the barrier properties of multilayer film were improved with the increase of the thickness of coating materials. The Young's modulus and tensile strength of PT multilayer film were slightly decreased, and their elongations at break were increased by coating. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1805–1811, 2013
The role of crosslinking treatment on the pore structure and water transmission of biocollagenic materials
Authors: Gil Roberto Rodríguez , Ruiz Begoña , Lozano Matilde Santiago , Fuente Enrique
Published: May 2013

The knowledge of the factors involved in the water transmission through collagen fibrous network of skin and leather is essential in the manufacture of materials that will give improved service and maintain a sufficiently high level of breathability and permeability to assure comfort to the wearer. The study of the structure and connectivity of the pores in the skin and leather is essential since it influences the heat and mass transport processes. This research study focuses on the porous structure and water vapor permeability of animal skin after it has been subjected to different treatments, such as pickling or tanning with chromium salts, or vegetable tannins. The obtained data indicated that surface groups, inorganic matter, and pore size distribution have influence on the water transmission. Water vapor adsorption isotherms showed pickled skin to have a greater adsorption capacity at a higher relative humidity, whereas vegetable‐tanned leather was found to be the sample with the lowest adsorption at higher relative humidity probably due to its greater density, lower accessibility of the functional groups, and wider distribution of pore sizes than the other materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1812–1822, 2013
Pressure‐crystallized piezoelectric structures in binary fullerene C70/poly(vinylidene fluoride) based composites
Authors: Zhang Daopeng , Tian Pengfei , Chen Xin , Lu Jun , Huang Rui
Published: May 2013

The effective fabrication of polar crystalline structures of poly (vinylidene fluoride) (PVDF), such as beta and gamma, is crucial to the development of piezoelectric polymer devices. In this study, we report the effect of pressure on binary fullerene C70/PVDF‐based composite with an overall good C70 dispersion, which was prepared by an easy physical and mechanical route. The C70/PVDF composites were crystallized in a piston‐cylinder high‐pressure apparatus, and the polymeric crystalline structures totally with extended‐chain piezoelectric beta‐ or gamma‐form lamellae were successfully achieved in the composite samples by varying temperature, pressure, crystallization time, and composite composition. The c‐axis thickness of the extended‐chain beta‐form lamellae of PVDF in the composites increased and decreased with the increase of the applied temperature and pressure, respectively, and it increased with the increase of crystallization time. Although C70 was found to be negative for the rapid formation of beta‐form PVDF crystals, it played an important role in the growth of a beta‐form PVDF nanowire with extended‐chain crystalline substructures. The template‐free formation of such piezoelectric nanowires was attributed to a C70‐induced self‐assembly of the polymer, driven by physical interactions at high pressure. The pressure‐crystallized C70/PVDF composites, self‐reinforced with unique one‐dimensional piezoelectric structures, may diversify niche applications in advanced functional polymeric devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1823–1833, 2013
The implementation of clay modeling and rat dissection into the human anatomy and physiology curriculum of a large urban community college
Authors: Haspel Carol , Motoike Howard K. , Lenchner Erez
Published: May 2013

After a considerable amount of research and experimentation, cat dissection was replaced with rat dissection and clay modeling in the human anatomy and physiology laboratory curricula at La Guardia Community College (LAGCC), a large urban community college of the City University of New York (CUNY). This article describes the challenges faculty overcame and the techniques used to solve them. Methods involved were: developing a laboratory manual in conjunction with the publisher, holding training sessions for faculty and staff, the development of instructional outlines for students and lesson plans for faculty, the installation of storage facilities to hold mannequins instead of cat specimens, and designing mannequin clean‐up techniques that could be used by more than one thousand students each semester. The effectiveness of these curricular changes was assessed by examining student muscle practical examination grades and the responses of faculty and students to questionnaires. The results demonstrated that the majority of faculty felt prepared to teach using clay modeling and believed the activity was effective in presenting lesson content. Students undertaking clay modeling had significantly higher muscle practical examination grades than students undertaking cat dissection, and the majority of students believed that clay modeling was an effective technique to learn human skeletal, respiratory, and cardiovascular anatomy, which included the names and locations of blood vessels. Furthermore, the majority of students felt that rat dissection helped them learn nervous, digestive, urinary, and reproductive system anatomy. Faculty experience at LAGCC may serve as a resource to other academic institutions developing new curricula for large, on‐going courses. Anat Sci Educ. 7: 38–46. © 2013 American Association of Anatomists.
The dissection room experience: A factor in the choice of organ and whole body donation—A Nigerian survey
Authors: Anyanwu Emeka G. , Obikili Emmanuel N. , Agu Augustine U.
Published: May 2013

The psychosocial impact of human dissection on the lives of medical and health science students has been noted. To assess the impact of the dissection room experience on one's willingness to become a whole body and organ donor, the attitudes of 1,350 students and professionals from the medical, health, and non‐health related disciplines to body and organ donation were studied. The participants were broken into categories according to degree of exposure to human dissection. Participants who were never exposed to the dissection experience showed more willingness to donate their bodies than those who were exposed. With the exception of the physiotherapy department, the students and professionals from the health science departments who were exposed to the dissection room but never engaged in dissection showed the most unwillingness to donate their bodies (P< 0.001). An unwillingness to donate oneself was noted as one of the negative impacts associated with exposure to the dissection room. Willingness to donate an organ correlated positively with the level of exposure to the dissection room (P< 0.001). Most of the reasons for unwillingness were traceable to negative perceptions of the dissection room as a result of poor and disrespectful management of the human cadavers. Anat Sci Educ. 7: 56–63. © 2013 American Association of Anatomists.
An enriched multimedia eBook application to facilitate learning of anatomy
Authors: Stirling Allan , Birt James
Published: May 2013

This pilot study compared the use of an enriched multimedia eBook with traditional methods for teaching the gross anatomy of the heart and great vessels. Seventy‐one first‐year students from an Australian medical school participated in the study. Students' abilities were examined by pretest, intervention, and post‐test measurements. Perceptions and attitudes toward eBook technology were examined by survey questions. Results indicated a strongly positive user experience coupled with increased marks; however, there were no statistically significant results for the eBook method of delivery alone outperforming the traditional anatomy practical session. Results did show a statistically significant difference in the final marks achieved based on the sequencing of the learning modalities. With initial interaction with the multimedia content followed by active experimentation in the anatomy lab, students' performance was improved in the final test. Obtained data support the role of eBook technology in modern anatomy curriculum being a useful adjunct to traditional methods. Further study is needed to investigate the importance of sequencing of teaching interventions. Anat Sci Educ. 7: 19–27. © 2013 American Association of Anatomists.
Rational Design of Anode Materials Based on Group IVA Elements (Si, Ge, and Sn) for Lithium‐Ion Batteries
Authors: Wu Xing‐Long , Guo Yu‐Guo , Wan Li‐Jun
Published: May 2013

Lithium‐ion batteries (LIBs) represent the state‐of‐the‐art technology in rechargeable energy‐storage devices and they currently occupy the prime position in the marketplace for powering an increasingly diverse range of applications. However, the fast development of these applications has led to increasing demands being placed on advanced LIBs in terms of higher energy/power densities and longer life cycles. For LIBs to meet these requirements, researchers have focused on active electrode materials, owing to their crucial roles in the electrochemical performance of batteries. For anode materials, compounds based on Group IVA (Si, Ge, and Sn) elements represent one of the directions in the development of high‐capacity anodes. Although these compounds have many significant advantages when used as anode materials for LIBs, there are still some critical problems to be solved before they can meet the high requirements for practical applications. In this Focus Review, we summarize a series of rational designs for Group IVA‐based anode materials, in terms of their chemical compositions and structures, that could address these problems, that is, huge volume variations during cycling, unstable surfaces/interfaces, and invalidation of transport pathways for electrons upon cycling. These designs should at least include one of the following structural benefits: 1) Contain a sufficient number of voids to accommodate the volume variations during cycling; 2) adopt a “plum‐pudding”‐like structure to limit the volume variations during cycling; 3) facilitate an efficient and permanent transport pathway for electrons and lithium ions; or 4) show stable surfaces/interfaces to stabilize the in situ formed SEI layers.
More robust and better: a multiple kernel support vector machine ensemble approach for traffic incident detection
Authors: Xiao Jianli , Gao Xiang , Kong Qing‐Jie , Liu Yuncai
Published: May 2013

This paper presents a multiple kernel support vector machine (MKL‐SVM) ensemble algorithm to detect traffic incidents. It uses resampling technology to generate training set, test set, and training subset firstly; then uses different training subsets to train individual MKL‐SVM classifiers; and finally introduces ensemble methods to construct MKL‐SVM ensemble to detect traffic incidents. Extensive experiments have been performed to evaluate the performances of the four algorithms: standard SVM, SVM ensemble, MKL‐SVM, and the proposed algorithm (MKL‐SVM ensemble). The experimental results show that the proposed algorithm has the best comprehensive performances in traffic incidents detection. To achieve better performances, the proposed algorithm needs less individual classifiers to construct the ensemble than SVM ensemble algorithm. Thus, compared with SVM ensemble algorithm, the complexity of the ensemble classifier of the proposed algorithm is reduced greatly. Conveniently, the proposed algorithm also avoids the burden of selecting the appropriate kernel function and parameters. Copyright © 2013 John Wiley & Sons, Ltd.
Large‐scale production of diesel‐like biofuels – process design as an inherent part of microorganism development
Authors: Cuellar Maria C. , Heijnen Joseph J. , van der Wielen Luuk A. M.
Published: May 2013

Industrial biotechnology is playing an important role in the transition to a bio‐based economy. Currently, however, industrial implementation is still modest, despite the advances made in microorganism development. Given that the fuels and commodity chemicals sectors are characterized by tight economic margins, we propose to address overall process design and efficiency at the start of bioprocess development. While current microorganism development is targeted at product formation and product yield, addressing process design at the start of bioprocess development means that microorganism selection can also be extended to other critical targets for process technology and process scale implementation, such as enhancing cell separation or increasing cell robustness at operating conditions that favor the overall process. In this paper we follow this approach for the microbial production of diesel‐like biofuels. We review current microbial routes with both oleaginous and engineered microorganisms. For the routes leading to extracellular production, we identify the process conditions for large scale operation. The process conditions identified are finally translated to microorganism development targets. We show that microorganism development should be directed at anaerobic production, increasing robustness at extreme process conditions and tailoring cell surface properties. All the same time, novel process configurations integrating fermentation and product recovery, cell reuse and low‐cost technologies for product separation are mandatory. This review provides a state‐of‐the‐art summary of the latest challenges in large‐scale production of diesel‐like biofuels.
Optimizing the Structure of 4‐Dialkylamino‐α,α‐diarylprolinol Ethers as Catalysts for the Enantioselective Cyclopropanation of α,β‐Unsaturated Aldehydes in Water
Authors: Martínez Jose I. , Reyes Efraim , Uria Uxue , Carrillo Luisa , Vicario Jose L.
Published: May 2013

We optimized the structure of a new family of chiral diarylprolinol‐type organocatalysts with improved performances in conjugate addition reactions performed in water and proceeding under the iminium activation manifold. The principles behind the catalyst design were, firstly, the incorporation of a tertiary amino group at the 4‐position of the pyrrolidine scaffold, which can facilitate the reaction by providing a basic site that favors deprotonation of the pronucleophile, and, secondly, a bulky diaryltrialkylsilyloxymethyl group maintained at the 2‐position to control the iminium ion geometry and to provide the required steric bias for face stereoselection. The nature of this 4‐dialkylamino group and the relative 2,4‐configuration was optimized and the resulting catalyst proved its efficiency in the catalytic enantioselective cyclopropanation of α,β‐unsaturated aldehydes using water as the reaction solvent. Moreover, the reaction was studied by computational methods, which indicated that the overall transformation proceeded through a cascade Michael/α‐alkylation sequence, in which the first iminium‐mediated Michael addition reaction was the rate‐determining step and also the step at which stereochemical information was transferred from the catalyst to the products.
Thioamides: Versatile Bonds To Induce Directional and Cooperative Hydrogen Bonding in Supramolecular Polymers
Authors: Mes Tristan , Cantekin Seda , Balkenende Dirk W. R. , Frissen Martijn M. M. , Gillissen Martijn A. J. , De Waal Bas F. M. , Voets Ilja K. , Meijer E. W. , Palmans Anja R. A.
Published: May 2013

The amide bond is a versatile functional group and its directional hydrogen‐bonding capabilities are widely applied in, for example, supramolecular chemistry. The potential of the thioamide bond, in contrast, is virtually unexplored as a structuring moiety in hydrogen‐bonding‐based self‐assembling systems. We report herein the synthesis and characterisation of a new self‐assembling motif comprising thioamides to induce directional hydrogen bonding. N,N′,N′′‐Trialkylbenzene‐1,3,5‐tris(carbothioamide)s (thioBTAs) with either achiral or chiral side‐chains have been readily obtained by treating their amide‐based precursors with P2S5. The thioBTAs showed thermotropic liquid crystalline behaviour and a columnar mesophase was assigned. IR spectroscopy revealed that strong, three‐fold, intermolecular hydrogen‐bonding interactions stabilise the columnar structures. In apolar alkane solutions, thioBTAs self‐assemble into one‐dimensional, helical supramolecular polymers stabilised by three‐fold hydrogen bonding. Concentration‐ and temperature‐dependent self‐assembly studies performed by using a combination of UV and CD spectroscopy demonstrated a cooperative supramolecular polymerisation mechanism and a strong amplification of supramolecular chirality. The high dipole moment of the thioamide bond in combination with the anisotropic shape of the resulting cylindrical aggregate gives rise to sufficiently strong depolarised light scattering to enable depolarised dynamic light scattering (DDLS) experiments in dilute alkane solution. The rotational and translational diffusion coefficients, Dtrans and Drot, were obtained from the DDLS measurements, and the average length, L, and diameter, d, of the thioBTA aggregates were derived (L=490 nm and d=3.6 nm). These measured values are in good agreement with the value Lw=755 nm obtained from fitting the temperature‐dependent CD data by using a recently developed equilibrium model. This experimental verification validates our common practice for determining the length of BTA‐based supramolecular polymers from model fits to experimental CD data. The ability of thioamides to induce cooperative supramolecular polymerisation makes them effective and broadly applicable in supramolecular chemistry.
Catalytic Disproportionation of the Superoxide Intermediate from Electrochemical O2 Reduction in Nonaqueous Electrolytes
Authors: Zheng Dong , Wang Qiang , Lee Hung‐Sui , Yang Xiao‐Qing , Qu Deyang
Published: May 2013

Tris(pentafluorophenyl)borane (TPFPB) was found to be an efficient catalyst for rapid superoxide (O2−) disproportionation. The kinetics for the catalytic disproportionation reaction is much faster than the reaction between O2− and propylene carbonate. Therefore, the negative impact of the reaction between the electrolyte and O2− produced by the O2 reduction is minimized. The cathodic current for O2 reduction can be doubled in the presence of TPFPB. The high reduction current resulted from the pseudo two‐electron O2‐reduction reaction due to the replenishment of O2 at the electrode surface. This discovery could lead to a new avenue for the development of high‐capacity, high‐rate, rechargeable Li–air batteries.
Enzyme‐Controlled Sensing–Actuating Nanomachine Based on Janus Au–Mesoporous Silica Nanoparticles
Authors: Villalonga Reynaldo , Díez Paula , Sánchez Alfredo , Aznar Elena , Martínez‐Máñez Ramón , Pingarrón José M.
Published: May 2013

Novel Janus nanoparticles with Au and mesoporous silica faces on opposite sides were prepared using a Pickering emulsion template with paraffin wax as the oil phase. These anisotropic colloids were employed as integrated sensing–actuating nanomachines for enzyme‐controlled stimuli‐responsive cargo delivery. As a proof of concept, we demonstrated the successful use of the Janus colloids for controlled delivery of tris(2,2’‐bipyridyl) ruthenium(II) chloride from the mesoporous silica face, which was grafted with pH‐sensitive gatelike scaffoldings. The release was mediated by the on‐demand catalytic decomposition of urea by urease, which was covalently immobilized on the Au face.
Fabrication of Ag Nanoparticles Embedded in TiO2 Nanotubes: Using Electrospun Nanofibers for Controlling Plasmonic Effects
Authors: Jung Mi‐Hee , Yun Yong Ju , Chu Moo‐Jung , Kang Man Gu
Published: May 2013

Composites of electrospun poly(ethylene oxide) (PEO) fibers and silver nanoparticles (Ag NPs) were used as a soft template for coating with TiO2 by atomic layer deposition (ALD). Whereas the as‐deposited TiO2 layers on PEO fibers and Ag NPs were completely amorphous, the TiO2 layers were transformed into polycrystalline TiO2 nanotubes (NTs) with embedded Ag NPs after calcination. Their plasmonic effect can be controlled by varying the thickness of the dielectric Al2O3 spacer between Ag NPs and dye molecules by means of the ALD process. Electronic and spectroscopic analyses demonstrated enhanced photocurrent generation and solar‐cell performance due to the intense electromagnetic field of the dye resulting from the surface plasmon effect of the Ag NPs.
Recombination of Lophyl Radicals in Pyrrolidinium‐Based Ionic Liquids
Authors: Berdzinski Stefan , Horst Joachim , Straßburg Petra , Strehmel Veronika
Published: May 2013

The recombination of photolytically generated lophyl radicals has been investigated by UV/Vis spectroscopy in 1‐alkyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl)imides (NTf2) in comparison with 1‐butyl‐3‐methylimidazolium NTf2, dimethyl sulfoxide, and triacetin. The 1‐alkyl‐1‐methylpyrrolidinium‐based ionic liquids contain an alkyl substituent varying between butyl and decyl groups. Optically pure ionic liquids are used in these studies. Temperature‐dependent investigation of lophyl radical recombination shows an increase in the radical recombination rate with increasing temperature in each solvent, which is caused by decreasing viscosity with increasing temperature. Furthermore, the viscosity of the 1‐alkyl‐1‐methylpyrrolidinium NTf2 increases nearly linearly within the row of these ionic liquids. In contrast, the recombination of the photolytically generated lophyl radicals is significantly faster in the ionic liquids than in the traditional organic solvents under investigation. Moreover, the recombination rate increases with the length of the alkyl chain bound at the cation of the ionic liquid at a given temperature. This may be caused by an increase in the extent of lophyl radical recombination within the solvent cage. Solvent cage effects dominate in the case of lophyl radical recombination in ionic liquids bearing a long alkyl chain or if the temperature is near the melting temperature of the ionic liquid. The positive value of the activation entropy supports this hypothesis. The results obtained are important for discussion of bimolecular radical reactions in ionic liquids.
Assessing main death pathways in T lymphocytes from HIV infected individuals
Authors: Massanella Marta , Curriu Marta , Carrillo Jorge , Gómez Elisabet , Puig Jordi , Navarro Jordi , Dalmau Judith , Martínez‐Picado Javier , Crespo Manel , Cabrera Cecilia , Negredo Eugènia , Clotet Bonaventura , Blanco Julià
Published: May 2013

Increased lymphocyte death is a hallmark of human immunodeficiency virus (HIV) infection. Although virological factors have been linked to this phenomenon, increased cell death rates are still observed in treated individuals in which viral replication is halted. To understand the nature of this remaining altered cell death, we have developed a simple and fast assay to assess major cell death pathways in lymphocytes isolated from HIV‐infected individuals. The combination of three factors: (i) antibody staining to identify CD3+CD4+ and CD3+CD8+ cells, (ii) assessment of mitochondrial and plasma membrane function using DiOC6(3) or JC‐1 probes and vital dyes, and (iii) caspase inhibition, allowed for the quantification of caspase‐independent and ‐dependent cell death in CD4 and CD8 T cells. The latter mechanism was divided in intrinsic and extrinsic apoptotic pathways according to the sensitivity of the dissipation of mitochondrial membrane potential to Z‐VAD‐fmk or Q‐VD‐oPH treatment. Our data show similar results for both caspase inhibitors in treated infected individuals, whereas Q‐VD‐oPH showed a more potent inhibition in viremic individuals, yielding lower levels of intrinsic apoptosis. Comparison of DiOC6(3) and JC‐1 probes yielded similar results in CD4 T cells, allowing for a clear definition of death mechanism in these cells. However, in CD8 T‐cells, JC‐1 showed heterogeneous staining and detected significantly lower levels of cell death with a higher contribution of intrinsic apoptosis. In conclusion, we provide a simple method to assess CD4 T‐cell death mechanisms in HIV‐infected individuals. The reasons and consequences of mitochondrial heterogeneity in CD8 T‐cells require further evaluation. © 2012 International Society for Advancement of Cytometry
Synthesis and Glycosidase Inhibition Studies of 5‐Methyl‐Substituted Tetrahydroxyindolizidines and ‐pyrrolizidines Related to Natural Hyacinthacines B
Authors: Martella Daniele , Cardona Francesca , Parmeggiani Camilla , Franco Francisco , Tamayo Juan A. , Robina Inmaculada , Moreno‐Clavijo Elena , Moreno‐Vargas Antonio J. , Goti Andrea
Published: May 2013

The synthesis of three tetrahydroxyindolizidines and one tetrahydroxypyrrolizidine related to natural hyacinthacines B and their biological evaluation as glycosidase inhibitors is reported. The target molecules were obtained through highly stereoselective cycloadditions between sugriched allylic and homoallylic alcohols. This allowed the installation of a methyl group at C5 – a common feature of many natural hyacinthacines – with high control over the stereoselectivity. The new compounds inhibit amyloglucosidase from Aspergillus niger and β‐glucosidase from almonds. Compound 1 is a competitive inhibitor of amyloglucosidase and shows a fair selectivity towards this enzyme. The presence of C5‐Me substitution in indolizidines 2 and 3 slightly diminishes the inhibitory activity towards amyloglucosidase whereas it improves the inhibitory properties towards β‐glucosidase.
Urea Assisted Synthesis of Flower Like CuO Nanostructures and Their Chemical Sensing Application for the Determination of Cadmium Ions
Authors: Khun K. , Ibupoto Z. H. , Willander M.
Published: May 2013

The novel nanostructures of CuO with improved morphology are strongly required for the development of devices with enhanced performance. In this study flower like nanostructures of CuO are synthesized by hydrothermal method using urea as tuning material for the morphology of CuO during the growth process. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques were used for the characterization of these nanostructures. The nanostructures are highly dense, uniform and well aligned on the gold coated glass substrate. Moreover, CuO nanostructures exhibited pure phase of CuO. These novel CuO nanostructures were potentially used for the construction of cadmium ion sensor by functionalizing with tetrathia‐12‐crown‐4 a selective cadmium ion ionophore. The proposed cadmium ion sensor has detected the wide range of cadmium ion concentrations from 1.0×10−9–1.0×10−1 M with a sensitivity of 29.3±0.3 mV/decade and also a fast response time of less than 10.0 s is demonstrated. CuO nanostructures based cadmium ion selective electrode has also shown excellent reproducibility, repeatability, selectivity, and stability. The sensor electrode was also used as indicator electrode for the confirmation of practical utility and the obtained result describes the good behavior of the sensor in the potentiometric titration for the determination of cadmium ions.
From Electrode Surface Fouling to Sensitive Electroanalytical Determination of Phenols
Authors: Kawde Abdel‐Nasser , Morsy Mohamed A. , Odewunmi Nurudeen , Mahfouz Wael
Published: May 2013

The present investigation of phenol and chlorophenols is conducted on the surface of glassy carbon by cyclic and square wave stripping voltammetry, and by Fourier‐transform infrared spectroscopy. The surface fouling is accompanied by the appearance of reversible peaks at lower potential range (+0.1 to+0.4 V), that grew up with CV‐cycling and attributed to the electro‐redox reactions of formed polymer film via electropolymerization. The electroanalytical monitoring of formed polymer oxidation peaks improved both sensitivity and detection limit by 35 and 10 times, respectively. The FT‐IR supported semiempirical prediction attributes the electropolymerization to the formation of ortho‐para and/or ortho‐meta CC coupled‐system.
Organic/Water Interface Electrochemistry for the Direct Detection of a Model Pesticide in Soybean Oil
Authors: Maynart M. C. , Silva R. M. P. , Suffredini H. B.
Published: May 2013

An electrochemical methodology was applied directly at an organic/water interface to detect a pesticide directly in oil, without the necessity of pre‐treatment of the sample. The oil phase was composed of soybean oil contaminated with carbendazim (methyl‐2‐benzimidazolecarbamate), and the aqueous phase consisted of a conventional BrittonRobinson buffer with a pH of 2. A boron‐doped diamond (BDD) electrode was placed directly at the interface of the two immiscible liquids. The ionic strength played an important role in the oxidation of carbendazim in our interfacial studies, as indicated by the oxidation currents varying from zero to 12 µA, depending on the position of the electrode.
Model updating method for substructure pseudo‐dynamic hybrid simulation
Authors: Kwon Oh‐Sung , Kammula Viswanath
Published: May 2013

Substructure hybrid simulation has been actively investigated and applied to evaluate the seismic performance of structural systems in recent years. The method allows simulation of structures by representing critical components with physically tested specimens and the rest of the structure with numerical models. However, the number of physical specimens is limited by available experimental equipment. Hence, the benefit of the hybrid simulation diminishes when only a few components in a large system can be realistically represented. The objective of the paper is to overcome the limitation through a novel model updating method. The model updating is carried out by applying calibrated weighting factors at each time step to the alternative numerical models, which encompasses the possible variation in the experimental specimen properties. The concept is proposed and implemented in the hybrid simulation framework, UI‐SimCor. Numerical verification is carried out using two‐DOF systems. The method is also applied to an experimental testing, which proves the concept of the proposed model updating method. Copyright © 2013 John Wiley & Sons, Ltd.
Multidegrees‐of‐freedom effective force testing: a feasibility study and robust stability assessment
Authors: Nakata Narutoshi , Krug Erin
Published: May 2013

This paper presents a feasibility study of multidegrees‐of‐freedom effective force testing (MDOF‐EFT). The study is intended to facilitate the development of a force feedback controller and investigation of performance as well as robustness of MDOF‐EFT. First, the dynamics of MDOF‐EFT systems are analytically investigated. Analytical transfer functions of the control plant, the valve‐to‐force relations, showed that the plant is dynamically coupled and the natural frequencies of test structures are the transmission zeros of the plant. Using a set of model parameters from a previous study, a case study that includes controller design, numerical simulations and robust stability assessment is performed. A decoupling loop shaping (DLS) controller consisting of a pseudo inverse of the plant and second‐order loop shaping controllers is adopted as the force feedback controller. It is shown that the DLS controller provides a stable control system while successfully decoupling the control loops and compensating the control‐structure interaction. Numerical simulations demonstrate that the DLS controller enables tracking of static and dynamic forces for multiple actuators. Robust stability of MDOF‐EFT with the DLS controller is assessed using Monte Carlo simulation. The stochastic simulation results show that the DLS controller is stable and robust, providing sufficient stability margins for uncertain models with maximum 50% errors in the estimated system parameters. This paper demonstrates that MDOF‐EFT is feasible with the DLS controller and can be implemented in experimental laboratories. Copyright © 2013 John Wiley & Sons, Ltd.
Arrhenius rheology versus Frank‐Kamenetskii rheology—Implications for mantle dynamics
Authors: Stein C. , Hansen U.
Published: May 2013

The viscosity of planetary mantle material is strongly temperature dependent. This dependence is described by an Arrhenius law. But for the realistic viscosity contrast that appears over the depth of the mantle, strong gradients in the upper thermal boundary layer occur. These strong gradients are not realizable in numerical models. Therefore, the Frank‐Kamenetskii approximation, leading to a linearized exponential viscosity function, is commonly used. Much research on the plate‐mantle system has been done applying the Frank‐Kamenetskii rheology. The question though still arises, if these results can be reproduced when using the Arrhenius law. Here it has to be kept in mind, that in numerical models the realistic viscosity contrast appearing over the mantle can neither be coped with by the Arrhenius nor the Frank‐Kamenetskii approach. Thus, the computational aspects to date only allow for viscosity contrasts being moderate as compared to realistic values and extrapolations to planet‐like values have to be made for both rheologies. Comparing results obtained by the commonly used forms of the Arrhenius and the Frank‐Kamenetskii approach, we observe the same change in flow behavior from mobile‐lid to stagnant‐lid convection. The differences are only of quantitative nature: In the stagnant‐lid regime, some Arrhenius formulations lead to a thinner top boundary layer which results in values of lithospheric thicknesses being more realistic. Here it has to be noted that different forms of the Arrhenius law have been used which differ among themselves. When properly scaled, the differences between the Frank‐Kamenetskii and Arrhenius rheology can, however, be strongly diminished. To understand general features in the plate tectonics‐mantle convection system an additional stress dependence of the viscosity has to be considered. The discrepancies between the various viscosity formulations are then of even less importance, because for an Earth‐like convection regime, the top viscosity is more strongly influenced by the stress dependence rather than by the temperature dependence.
Patient and carer views on participating in clinical trials for prodromal Alzheimer's disease and mild cognitive impairment
Authors: Lawrence Vanessa , Pickett James , Ballard Clive , Murray Joanna
Published: May 2013

Objective

There is great interest in conducting clinical trials of disease‐modifying therapies in the prodromal (early, pre‐dementia), asymptomatic stages of Alzheimer's disease. Diagnostic biomarker tests offer a means of identifying prodromal patients, but it is unclear how potential participants feel about their use. Deciding whether to take part in a clinical trial is a complex process in which eligible participants must balance risks and discomforts against uncertain benefits. We sought to explore the views of potential participants through qualitative research methods.

Methods

Focus groups with people with early memory problems, current and former family carers explored attitudes towards participating in clinical trials in the prodromal stages of the disease, using an example of anti‐amyloid antibody‐therapy (immunotherapy), which are currently in development.

Results

Despite the complexities involved, almost all participants had a clear idea about whether they, personally, would like to take part. Many were highly motivated to obtain an unambiguous diagnosis, regardless of their desire to participate in a clinical trial. Participants expressed minimal concern regarding the risk of adverse events associated with immunotherapy, whereas certain tests and trial procedures provoked greater anxiety. People with memory problems were found to assess the study demands in relation to their own priorities and circumstances.

Conclusions

The priorities of patients might be different to clinicians and those who design and regulate clinical trials. Patient views can be used to inform the ethical debate around the disclosure of biomarker status, the design of clinical trials and the content of trial information. Copyright © 2013 John Wiley & Sons, Ltd.
Oceanic hindcast simulations at high resolution suggest that the Atlantic MOC is bistable
Authors: Deshayes J. , Tréguier A.‐M. , Barnier B. , Lecointre A. , Sommer J. Le , Molines J.‐M. , Penduff T. , Bourdallé‐Badie R. , Drillet Y. , Garric G. , Benshila R. , Madec G. , Biastoch A. , Böning C. W. , Scheinert M. , Coward A. C. , Hirschi J. J.‐M.
Published: May 2013

All climate models predict a freshening of the North Atlantic at high latitude that may induce an abrupt change of the Atlantic Meridional Overturning Circulation (hereafter AMOC) if it resides in the bistable regime, where both a strong and a weak state coexist. The latter remains uncertain as there is no consensus among observations and ocean reanalyses, where the AMOC is bistable, versus most climate models that reproduce a mono‐stable strong AMOC. A series of four hindcast simulations of the global ocean at 1/12° resolution, which is presently unique, are used to diagnose freshwater transport by the AMOC in the South Atlantic, an indicator of AMOC bistability. In all simulations, the AMOC resides in the bistable regime: it exports freshwater southward in the South Atlantic, implying a positive salt advection feedback that would act to amplify a decreasing trend in subarctic deep water formation as projected in climate scenarios.
Evaluation of the effects of a metabotropic glutamate receptor 5‐antagonist on electrically induced pain and central sensitization in healthy human volunteers
Authors: Kalliomäki J. , Huizar K. , Kågedal M. , Hägglöf B. , Schmelz M.
Published: May 2013

Background

This study aimed to investigate the effect of a single dose of the mGluR5‐antagonist AZD9272 on electrically induced pain, central sensitization and axon reflex flare.

Methods

This was a randomized, double‐blind, placebo‐controlled crossover study. Twenty‐five healthy male volunteers received a single oral dose of AZD9272 or placebo on two occasions separated by 10–20 days. Electrical stimulation with a constant current for 100 min delivered through intracutaneous electrodes inserted on the forearm was used to induce a stable level of pain (6 of 10 on a 0–10 numerical rating scale; NRS). Pain intensity was assessed every 10 min during stimulation. The area of punctate hyperalgesia, area of dynamic mechanical allodynia, and area and intensity of flare reaction were measured every 20 min during stimulation. The stimulation procedure, current intensity and measurements were identical at both treatment visits. The AUC0–100 min (area under curve, 100 min stimulation) was calculated for each variable. The AUC0–100 min for pain NRS and hyperalgesia area were defined as primary variables. Linear mixed effects models were used for the statistical analysis.

Results

Twenty‐one subjects completed the study per protocol. No significant differences were found between AZD9272 and placebo regarding any of the AUC0–100 min variables for pain NRS, hyperalgesia area, allodynia area, flare area or flare intensity. The plasma levels of AZD9272 were maximal during the pain measurements and corresponded to >50% brain mGluR5 receptor occupancy.

Conclusion

Single doses of the centrally acting mGluR5‐antagonist AZD9272 did not reduce C‐fibre evoked pain, central sensitization or flare reaction.
Ebselen Reduces the Toxicity of Mechlorethamine in A‐431 Cells via Inhibition of Apoptosis
Authors: Lulla Anju , Pino Maria A. , Piętka‐Ottlik Magdalena , Młochowski Jacek , Sparavalo Oleksiy , Billack Blase
Published: May 2013

A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen mustard mechlorethamine (HN2) in vitro. The test compounds included resveratrol, pterostilbene, vitamin C, ebselen, ebselen diselenide, and ebselen‐sulfur. Among them, ebselen demonstrated the highest degree of protection against HN2 toxicity. To this end, pretreatment of the cells with ebselen offered protection against the toxicant whereas no protection was observed when cells were first incubated with HN2 and then treated with ebselen. Significant increases in caspase 3 and caspase 9 activities were observed in response to HN2, and ebselen was found to reduce these effects. Taken together, the data presented here indicate that ebselen is an effective countermeasure to nitrogen mustard in vitro, which is worthy of future investigation in vivo. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:313‐322, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21490
Localization of Scopolamine Induced Electrocortical Brain Activity Changes, in Healthy Humans at Rest
Authors: Ramos Reis Pedro Miguel , Eckhardt Holger , Denise Pierre , Bodem Friedrich , Lochmann Matthias
Published: May 2013

To prevent the participants of parabolic flights from nausea they are optionally treated with subcutaneously injected antiemetic scopolamine. The range of side effects of this substance include reductions of the α‐2 frequency band. Previous studies, however, have given no information as to which generator centers are responsible for this effect. The objective of this study therefore, is to identify the cortex area that may be responsible for this effect. Six participants were subcutaneously administered 0.7 mg of scopolamine. EEG was recorded for 10 minutes before to 20 minutes after injection. Data preprocessing followed including filtering and artifact minimization. A statistical analysis was performed with sLORETA/eLORETA software for each subject over a time window from 3 minutes before to 17–20 minutes after scopolamine injection. Results show, that in the BA7, the precuneus, on both hemispheres suffered a α‐2 activity decrease in absolute power. The identified brain cortex center is an important hub with high connectivity and centrality values within the neural network. It contributes to the control of movement and to space orientation. Therefore, an activity alteration in this area can possibly explain the antiemetic effect of scopolamine and open a window to understand the origin of motion sickness.