bluuebunny/crossref_metadata_2025_split huggingface dataset:
When Overgrowth Bumps Into Cancer: The PTEN‐Opathies
Authors: MESTER JESSICA , ENG CHARIS 
Published: April 2013

AbstractPTEN is a dual‐specificity phosphatase and well‐known tumor suppressor gene. When functioning properly, it works in its canonical pathway to inhibit AKT/mTOR and MAPK signaling, leading to cell death and growth regulation. PTEN mutations cause dysregulation of these pathways, resulting in cellular proliferation and overgrowth. When germline mutations are present as in patients with PTEN Hamartoma Tumor Syndrome (PHTS), benign and malignant neoplasias occur as well as cerebral overgrowth and neurodevelopmental abnormalities. This review article will summarize recent laboratory and clinical investigations relating to PTEN, highlighting the overgrowth aspects of this syndrome and the molecular drivers behind these key phenotypes. Finally, therapies developed targeted the PI3K/AKT/mTOR pathway for other tumor predisposition syndromes will be discussed. © 2013 Wiley Periodicals, Inc.
Archaeology of brutal encounter: heritage and bomb testing on Bikini Atoll, Republic of the Marshall Islands
Authors: Brown Steve 
Published: April 2013

AbstractWhen the nude dancer, Micheline Bernardini, modelled the bikini at a public pool in Paris on 5 July 1946, the blaze of publicity that followed the unleashing of the fashion icon immediately trivialised the humanly willed catastrophe wrought on Bikini Atoll and its Indigenous inhabitants four days previously. Between 1946 and 1958, a total of 67 nuclear bomb tests were carried out in the Marshall Islands, including in 1954 the world's first deliverable hydrogen bomb, which vaporised three of Bikini's islands and produced radioactive fallout that resulted in the deaths of, and ill‐health effects for, Marshallese, American and Japanese people and for the atoll itself. Today, Bikini Atoll is almost uninhabited. This paper is based on a preliminary survey of the atoll and outlines the material traces of nuclear testing, which comprise profound landscape modifications and other physical evidence, including an experimental target fleet of sunken ships, buildings and infrastructure remains, and cultural plantings. Listing of Bikini Atoll on the World Heritage List in 2010 has (re)materialised and (re)imagined the cultural landscape of Bikini Atoll in a way that privileges the global story of bomb testing over the local narrative of lost homeland. However, I argue that the listing of Bikini Atoll is a subversive act coopted by both global and local actors in a way that is mutually beneficial.
Molluscan mulching at the margins: investigating the development of a South Island Māori variation on Polynesian hard mulch agronomy
Authors: Barber Ian 
Published: April 2013

AbstractHard mineral clast sediments applied to dry archaeological fields in the distant apical islands of the Polynesian triangle are frequently associated with sweet potato / kūmara (Ipomoea batatas (L) Lam.) cultivation. In a novel variation on this practice, north‐western South Island Māori deposited tuangi (Austrovenus stutchburyi (Wood, 1828)) mollusc beach valves to cap 10–20 cm deep planting holes or pits by or around the sixteenth century AD at Triangle Flat, Golden Bay. Discrete tuangi beach valve sediment had been extended over much of the larger field surface in association with shallow (<10 cm deep) planting depressions. Surface shell deposits would have suppressed weed growth, redirected radiant energy onto young kūmara plants, and conserved planting pit soil and moisture against disruptive and desiccating winds, respectively. The temporal extension of Triangle Flat shell sediment could be related to socio‐economic and political pressures to improve kūmara production from a fixed land unit. However, since climate change beginning in the sixteenth century brought cooler temperatures and eventually, stronger westerly winds to this region, it seems more likely that shell mulch was extended to maintain shallow planting soils and production in a colder, windier period. This local, kūmara‐focused development may have been encouraged by the opportunity to apply ritually safe and perhaps spiritually potent, uncooked tuangi beach shell to tapu cultivation surfaces.
Incremental Generalized Homogeneity, Observer Design and Semiglobal Stabilization
Authors: Battilotti Stefano 
Published: April 2013

AbstractThe notion of incremental generalized homogeneity is introduced, giving new results on semiglobal stabilization by output feedback and observer design and putting into a unifying framework the stabilization design for triangular (feedback/feedforward) and homogeneous systems. A state feedback controller and an asymptotic state observer are designed separately by dominating the generalized homogeneity degree of the nonlinearities with the degree of the linear approximation of the system and an output feedback controller is obtained according to a certainty‐equivalence principle.
Designed Synthesis of Well‐Defined Pd@Pt Core–Shell Nanoparticles with Controlled Shell Thickness as Efficient Oxygen Reduction Electrocatalysts
Authors: Choi Ran , Choi Sang‐Il , Choi Chang Hyuck , Nam Ki Min , Woo Seong Ihl , Park Joon T. , Han Sang Woo 
Published: April 2013

AbstractImproving the electrocatalytic activity and durability of Pt‐based catalysts with low Pt content toward the oxygen reduction reaction (ORR) is one of the main challenges in advancing the performance of polymer electrolyte membrane fuel cells (PEMFCs). Herein, a designed synthesis of well‐defined Pd@Pt core–shell nanoparticles (NPs) with a controlled Pt shell thickness of 0.4–1.2 nm by a facile wet chemical method and their electrocatalytic performances for ORR as a function of shell thickness are reported. Pd@Pt NPs with predetermined structural parameters were prepared by in situ heteroepitaxial growth of Pt on as‐synthesized 6 nm Pd NPs without any sacrificial layers and intermediate workup processes, and thus the synthetic procedure for the production of Pd@Pt NPs with well‐defined sizes and shell thicknesses is greatly simplified. The Pt shell thickness could be precisely controlled by adjusting the molar ratio of Pt to Pd. The ORR performance of the Pd@Pt NPs strongly depended on the thickness of their Pt shells. The Pd@Pt NPs with 0.94 nm Pt shells exhibited enhanced specific activity and higher durability compared to other Pd@Pt NPs and commercial Pt/C catalysts. Testing Pd@Pt NPs with 0.94 nm Pt shells in a membrane electrode assembly revealed a single‐cell performance comparable with that of the Pt/C catalyst despite their lower Pt content, that is the present NP catalysts can facilitate low‐cost and high‐efficient applications of PEMFCs.
Multiresponsive Viscoelastic Vesicle Gels of Nonionic C12EO4 and Anionic AzoNa
Authors: Wang Dong , Wei Guangcheng , Dong Renhao , Hao Jingcheng 
Published: April 2013

AbstractViscoelastic vesicle gels were prepared by mixing a nonionic surfactant, tetraethylene glycol monododecyl ether (C12EO4), and an anionic dye, sodium 4‐phenylazobenzoic acid (AzoNa). The gels, which were composed of multilamellar vesicles, were analyzed by cryogenic transmission electron microscopy (cryo‐TEM), freeze–fracture transmission electron microscopy (FF‐TEM), 2H NMR spectroscopy, and small‐angle X‐ray scattering (SAXS). The mechanism of vesicle‐gel formation is explained by the influence of anionic molecules on the bilayer bending modulus. Interestingly, the vesicle gels were observed to be sensitive to temperature, pH, and light. The viscoelastic vesicle gels respond to heat; they thin at lower temperatures and become thicker at higher temperatures. The vesicle gels are only stable from pH 7 to 11, and the gels become thinner outside of this range. UV light can also trigger a structural phase transition from micelles to multilamellar vesicle gels.
Catalytic Asymmetric Synthesis of Spirocyclic Azlactones by a Double Michael‐Addition Approach
Authors: Weber Manuel , Frey Wolfgang , Peters René 
Published: April 2013

AbstractSpirocyclic azlactones are shown to be useful precursors of cyclic quaternary amino acids, such as the constrained cyclohexane analogues of phenylalanine. These compounds are of interest as building blocks for the synthesis of artificial peptide analogues with controlled folds in the peptide backbone. They were prepared in the present study by a step‐ and atom‐economic catalytic asymmetric tandem approach, requiring two steps starting from N‐benzoyl glycine and divinylketones. The key of this protocol is the enantioselective formation of the azlactone spirocycles, which involves a PdII‐catalyzed double 1,4‐addition of an in situ generated azlactone intermediate to the dienone (a formal [5+1] cycloaddition). As the catalyst, a planar chiral ferrocene bispalladacycle was used. Mechanistic studies suggest a monometallic reaction pathway. Although the diastereoselectivity was found to be moderate, the enantioselectivity is usually high for the formation of the azlactone spirocycles, which contain up to three contiguous stereocenters. Spectroscopic studies have shown that the spirocycles often prefer a twist over a chair conformation of the cyclohexanone moiety.
Electronically Connected [n]Helicenes: Synthesis and Chiroptical Properties of Enantiomerically Pure (E)‐1,2‐Di([6]helicen‐2‐yl)ethenes
Authors: Roose Jesse , Achermann Stefan , Dumele Oliver , Diederich François 
Published: April 2013

AbstractWe synthesized stilbenoid (E)‐(P,P)‐ and (E)‐(M,M)‐[6]helicene dimers in enantiomerically pure form as part of a program aimed at the exploration of new strategies for the synthesis of large helicenes. The [2+2+2] cyclotrimerization of suitable triynes, reported by Starý and co‐workers, was applied for the preparation of a racemic 2‐hydroxymethylated [6]helicene precursor, which was conveniently resolved by HPLC on a chiral stationary phase. Two optically active helicenes were subsequently connected to the stilbenoid dimer by olefin metathesis. Electronic circular dichroism (ECD) studies of the stilbenoid ethen‐1,2‐diyl‐linked dimer revealed bathochromically shifted ECD bands with exceptionally large Cotton effects relative to those of the monomeric [6]helicenes or to that of a dimeric [6]helicene with a saturated ethan‐1,2‐diyl linker. These comparative studies, complemented by computational investigations, show that the pronounced chiroptical properties of the stilbenoid dimer originate from π‐conjugation between the two [6]helicene moieties and from the rigidity that results from conjugation. All attempts to form (P)‐[13]helicene by photocyclodehydrogenation of the stilbenoid (P,P)‐dimer were unsuccessful.
Actuator dynamics compensation based on upper bound delay for real‐time hybrid simulation
Authors: Wu Bin , Wang Zhen , Bursi Oreste S. 
Published: April 2013

SUMMARYReal‐time hybrid simulation represents a powerful technique capable of evaluating the structural dynamic performance by combining the physical simulation of a complex and rate‐dependent portion of a structure with the numerical simulation of the remaining portion of the same structure. Initially, this paper shows how the stability of real‐time hybrid simulation with time delay depends both on compensation techniques and on time integration methods. In particular, even when time delay is exactly known, some combinations of numerical integration and displacement prediction schemes may reduce the response stability with conventional compensation methods and lead to unconditional instability in the worst cases. Therefore, to deal with the inaccuracy of prediction and the uncertainty of delay estimation, a nearly exact compensation scheme is proposed, in which the displacement is compensated by means of an upper bound delay and the desired displacement is picked out by an optimal process. Finally, the advantages of the proposed scheme over conventional delay compensation techniques are shown through numerical simulation and actual tests. Copyright © 2013 John Wiley & Sons, Ltd.
Impact of machine‐type communications on energy and delay performance of random access channel in LTE‐advanced
Authors: Gerasimenko Mikhail , Petrov Vitaly , Galinina Olga , Andreev Sergey , Koucheryavy Yevgeni 
Published: April 2013

ABSTRACTMachine‐type communications (MTC) are a rapidly growing technology, which is expected to generate significant revenues to mobile network operators. In particular, smart grid is predicted to become one of the key MTC use cases that involves unattended meters autonomously reporting information to a grid infrastructure. With this research, we consider a typical smart metering MTC application scenario in the context of 3GPP LTE‐advanced wireless cellular system featuring a large number of devices connecting to the network near‐simultaneously. The resulting overload of the random access channel requires a novel evaluation methodology based on comprehensive analysis and simulations. In this paper, we target to complement a validated evaluation framework fully compatible with the 3GPP test cases with a thorough analysis of random access channel performance in overloaded MTC scenarios. We also look at the regular MTC operation, when the devices are sending their data after initial network entry has been performed. By including energy consumption into our methodology together with the conventional performance metrics, we aim at providing a complete and unified insight into MTC device operation, including its energy efficiency. Copyright © 2013 John Wiley & Sons, Ltd.
Enhanced Performance and Durability of a High Temperature Steam Electrolysis Stack
Authors: Mougin J. , Mansuy A. , Chatroux A. , Gousseau G. , Petitjean M. , Reytier M. , Mauvy F. 
Published: April 2013

AbstractHigh temperature steam electrolysis (HTSE) is one of the most promising ways for hydrogen mass production. If coupled to a CO2‐free electricity and a low cost heat source, this process is liable to a high efficiency. High levels of performance and durability, in association with cost‐effective stack and system components are the key points. To reach such goals, a low‐weight stack has been designed, keeping the advantages of the high performing and robust stack previously validated in terms of performance, durability, and cyclability [1], but aiming at reducing the cost by the use of thin interconnects. This low‐weight stack has demonstrated at the scale of a 3‐cell stack a good performance of –1.0 A cm–2 at 1.3 V at 800 °C. Before performing the durability test, preliminary studies at the cell level have been carried out to highlight the effect of two major operating parameters that are the current density and the steam conversion (SC) ratio, those studies being carried out at one temperature, 800 °C. Based on these results, optimized operating parameters have been defined to perform the durability test on the stack, that is –0.5 A cm–2 and a SC ratio of 25%. Degradation rates around 3–4% 1,000 h–1 have been measured. The thermal cyclability of this stack has also been demonstrated with one thermal cycle. Therefore it can be concluded that these results make HTSE technology getting closer to the objectives of performance, durability, thermal cyclability, and cost.
The Use of Methane‐Containing Syngas in a Solid Oxide Fuel Cell: A Comparison of Kinetic Models and a Performance Evaluation
Authors: Liu M. , Pourquie M. J. B. M. , Fan L. , Halliop W. , Cobas V. R. M. , Verkooijen A. H. M. , Aravind P. V. 
Published: April 2013

AbstractThe nickel‐based anodes of solid oxide fuel cells (SOFCs) can catalytically reform hydrocarbons, which make natural gas, gasification syngas, etc., become potential fuels in addition to hydrogen. SR and water–gas shift (WGS) often occur inside SOFCs when operated on these fuels. Their reaction rates affect the partial pressures of hydrogen and carbon monoxide, the local temperatures and the related Nernst voltages. Consequently, the reaction rates affect the electrochemical reactions in the fuel cell. Three different kinetic models were used to characterize methane SR in a tubular SOFC; the results of each model were evaluated and compared. The polarizations of the fuel cell results of these models were validated against experimental data. The performance of a fuel cell operated with different fuels and based on a selected kinetic model was further studied in terms of the anode oxygen partial pressure, the thermo‐electrochemical distribution, and the system level performance.
Cracking the ENCODE: From transcription to therapeutics
Authors: Mehta Gautam , Jalan Rajiv , Mookerjeee Rajeshwar P 
Published: April 2013

Abstract

The human genome encodes the blueprint of life, but the function of the vast majority of its nearly three billion bases is unknown. The Encyclopedia of DNA Elements (ENCODE) project has systematically mapped regions of transcription, transcription factor association, chromatin structure and histone modification. These data enabled us to assign biochemical functions for 80% of the genome, in particular outside of the well-studied protein-coding regions. Many discovered candidate regulatory elements are physically associated with one another and with expressed genes, providing new insights into the mechanisms of gene regulation. The newly identified elements also show a statistical correspondence to sequence variants linked to human disease, and can thereby guide interpretation of this variation. Overall, the project provides new insights into the organization and regulation of our genes and genome, and is an expansive resource of functional annotations for biomedical research.
Effects of oral 5‐hydroxytryptophan on a standardized planning task: insight into possible dopamine/serotonin interactions in the forebrain
Authors: Gendle Mathew H. , Young Erica L. , Romano Alexandra C. 
Published: April 2013

ObjectiveSeveral studies have suggested that exogenous administration of the serotonin precursor 5‐hydroxytryptophan (5‐HTP) can result in the ectopic production of serotonin in dopaminergic neurons and a concomitant reduction in dopamine release. This study tested this hypothesis using the Tower of London (TOL), a test of planning and executive control that is sensitive to changes in forebrain dopamine activity, but insensitive to alterations in serotonin.MethodsA sample of 68 undergraduates participated, and each received either three 50‐mg 5‐HTP capsules or placebos, and completed the TOL following a set absorption period.Results5‐HTP significantly lengthened the average time needed to complete each of the 10 trials of the TOL. 5‐HTP did not affect accuracy on this task.ConclusionsOral exogenous 5‐HTP disrupts dopaminergic function in the human forebrain. Copyright © 2013 John Wiley & Sons, Ltd.
Developing predictive systems models to address complexity and relevance for ecological risk assessment
Authors: Forbes Valery E , Calow Peter 
Published: April 2013

Abstract
Ecological risk assessments (ERAs) are not used as well as they could be in risk management. Part of the problem is that they often lack ecological relevance; that is, they fail to grasp necessary ecological complexities. Adding realism and complexity can be difficult and costly. We argue that predictive systems models (PSMs) can provide a way of capturing complexity and ecological relevance cost-effectively. However, addressing complexity and ecological relevance is only part of the problem. Ecological risk assessments often fail to meet the needs of risk managers by not providing assessments that relate to protection goals and by expressing risk in ratios that cannot be weighed against the costs of interventions. Once more, PSMs can be designed to provide outputs in terms of value-relevant effects that are modulated against exposure and that can provide a better basis for decision making than arbitrary ratios or threshold values. Recent developments in the modeling and its potential for implementation by risk assessors and risk managers are beginning to demonstrate how PSMs can be practically applied in risk assessment and the advantages that doing so could have. Integr Environ Assess Manag 2013;9:e75–e80. © 2013 SETAC
Mechanisms of the Statins Cytotoxicity in Freshly Isolated Rat Hepatocytes
Authors: Abdoli Narges , Heidari Reza , Azarmi Yadollah , Eghbal Mohammad Ali 
Published: April 2013

ABSTRACTStatins are potent drugs, used as lipid‐lowering agents in cardiovascular diseases. Hepatotoxicity is one of the serious adverse effects of statins, and the exact mechanism of hepatotoxicity is not yet clear. In this study, the cytotoxic effects of the most commonly used statins, that is, atorvastatin, lovastatin, and simvastatin toward isolated rat hepatocytes, were evaluated. Markers, such as cell death, reactive oxygen species (ROS) formation, lipid peroxidation, mitochondrial membrane potential, and the amount of reduced and oxidized glutathione in the statin‐treated hepatocytes, were investigated. It was found that the statins caused cytotoxicity toward rat hepatocytes dose dependently. An elevation in ROS formation, accompanied by a significant amount of lipid peroxidation and mitochondrial depolarization, was observed. Cellular glutathione reservoirs were decreased, and a significant amount of oxidized glutathione was formed. This study suggests that the adverse effect of statins toward hepatocytes is mediated through oxidative stress and the hepatocytes mitochondria play an important role in the statin‐induced toxicity. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:287‐294, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21485
Consider a Non‐Spherical Elephant: Computational Fluid Dynamics Simulations of Heat Transfer Coefficients and Drag Verified Using Wind Tunnel Experiments
Authors: Dudley Peter N. , Bonazza Riccardo , Porter Warren P. 
Published: April 2013

AbstractAnimal momentum and heat transfer analysis has historically used direct animal measurements or approximations to calculate drag and heat transfer coefficients. Research can now use modern 3D rendering and computational fluid dynamics software to simulate animal–fluid interactions. Key questions are the level of agreement between simulations and experiments and how superior they are to classical approximations. In this paper we compared experimental and simulated heat transfer and drag calculations on a scale model solid aluminum African elephant casting. We found good agreement between experimental and simulated data and large differences from classical approximations. We used the simulation results to calculate coefficients for heat transfer and drag of the elephant geometry. J. Exp. Zool. 319A:319–327, 2013. © 2013 © 2013 Wiley Periodicals, Inc.
Large deviations of the magnetic field from the Parker spiral in CRRs: Validity of the Schwadron model
Authors: Smith Edward J. 
Published: April 2013

AbstractA difference in solar wind speed inside and outside a Coronal Hole Boundary (CHB) causes the field and solar wind to expand rapidly with distance to form a Corotating Rarefaction Region (CRR). In the Parker model, field lines inside the CRR form spirals determined by the local solar wind speed. Observationally, however, CRR fields often diverge from the Parker spiral by tens of degrees and in a more radial direction. In a model developed by Schwadron (2002), in addition to the velocity gradient, the field lines rotate differentially across the CHB. The solar wind speed then varies along the field lines rather than remaining constant as in the Parker model. The plausibility of the model is supported by calculations using nominal model parameters that reproduce the systematic deviations from the Parker spiral. The present study establishes the validity of the model by comparing observations of nine CRRs between 1 and 4 AU with model predictions. Estimates are obtained for the width, velocity gradient, differential velocity of the CRR, and the transit time of the magnetic field. These parameters are obtained at the surface near 10 solar radii where the pressure of the coronal magnetic field first becomes balanced.