bluuebunny/crossref_metadata_2025 huggingface dataset:
Creep and Dynamic Mechanical Analysis Studies of Peroxide‐Crosslinked Ethylene‐Octene Copolymer
Authors: Theravalappil Rajesh , Svoboda Petr , Poongavalappil Sameepa , Svobodova Dagmar
Published: February 2012

An ethylene‐octene copolymer (EOC) (45 wt% octene) is crosslinked using dicumyl peroxide (DCP). Differential scanning calorimetry (DSC) reveals a very low melting temperature (50 °C). The network density is evaluated by gel content. While 0.2–0.3 wt% of peroxide leads only to a molecular weight increase (samples completely dissolved in xylene), 0.4–0.6 wt% of peroxide caused network formation. High‐temperature creep was measured at 70, 120, and 200 °C at three stress levels. At 200 °C and above 0.6 wt% of peroxide, degradation due to chain scission is observed by rubber process analyzer (RPA) and is again supported by creep measurements. Residual strain at 70 °C is found to improve with increasing peroxide level. Dynamic mechanical analysis (DMA) reveals a strong influence of peroxide content on storage modulus and tan δ, in particular in the range 30–200 °C.

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Bactericidal and Anticorrosion Properties in PVK/MWNT Nanocomposite Coatings on Stainless Steel
Authors: Santos Catherine M. , Milagros Cui Karina , Ahmed Farid , Tria Maria Celeste R. , Vergara Regina Aileen May V. , de Leon Al Christopher , Advincula Rigoberto C. , Rodrigues Debora F.
Published: February 2012

A PVK/MWNT nanocomposite coating on stainless steel is developed and tested for antimicrobial and anticorrosion properties. The coating is prepared via electrochemical deposition onto SS surfaces and is monitored using cyclic voltammetry. High‐resolution XPS measurements of the C 1s and N 1s regions are used to estimate the film composition. AFM shows a homogeneous thin film of several µm thickness with well‐defined globular domains. The bactericidal functionality of the electrodeposited film is demonstrated by its antibacterial activity against Escherichia coli, even with low MWNT loading (≈6%). The excellent anticorrosion property of the coating is demonstrated after 7 d of exposure to NaCl (0.5 M) solution.

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Effect of Silica‐Coated Poly(butyl methacrylate)‐block‐poly(methyl methacrylate) Double‐Shell Particles on the Mechanical Properties of PMMA Composites
Authors: Chakkalakal Golda Louis , Alexandre Michaël , Boschetti‐de‐Fierro Adriana , Abetz Volker
Published: February 2012

Silica nanoparticles with an average diameter of 12 nm are grafted with PBMA‐b‐PMMA double shells through typical sequential ATRP from bromoisobutyrate initiators anchored at the silica surface using an epoxysilane. A commercially available PMMA homopolymer is used for the preparation of composites with unmodified, silane‐modified and double‐shell‐modified silica particles. Good mechanical properties are obtained for silica double shell containing systems. The silica content in double shell particle systems is varied from 0 to 2.5 wt%. A significant improvement in impact properties is observed. The surface‐modified silica particles are characterized by ATR‐FTIR, NMR, GPC, and thermal analyses. TEM analysis is used to analyze the nature of dispersion of particles in the composites.

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Spaces of vector‐valued functions and their duals
Authors: Roth Walter
Published: February 2012

We consider spaces of continuous vector‐valued functions on a locally compact Hausdorff space, endowed with classes of locally convex topologies, which include and generalize various known ones such as weighted space‐ or inductive limit‐type topologies. The main result states that every continuous linear functional on such a function space can be expressed as an integral with respect to some canonical (dual space‐valued) vector measure.
Solubilization of a π‐Conjugating Hydrophobic Dendrimer in Aqueous Media
Authors: Imaoka Takane , Katsurayama Makoto , Yamanoi Yoshinori , Nishihara Hiroshi , Yamamoto Kimihisa
Published: February 2012

Phenylazomethine dendrimers, which can be used as the template for precise metal nanoparticles, are soluble only in aprotic media. The use of a specific surfactant enabled their solubilization in aqueous solutions. Under dilute condition, they formed discrete micelles with a size close to the that of the dendrimer. Condensation resulted in their aggregation; however, they remained in a homogeneous solution without precipitation. Furthermore, each micelle was well isolated. The triplet‐excited state of the zinc porphyrin core in the micelles was significantly stable, suggesting the formation of rigid core‐shell micelles preventing any external molecules from approaching to the core.
Differentiation of isomeric amino acid residues in proteins and peptides using mass spectrometry
Authors: Hurtado Pilar Perez , O'Connor Peter B.
Published: February 2012

Characterization and differentiation of isomers in biological macromolecules using mass spectrometry is one of the most significant challenges facing scientists in the field. The capability of high‐resolution MS instruments along with the development of new fragmentation methods now provides the ability to indirectly differentiate between some isomers. This ability has enabled mass spectrometry to evolve into a multidisciplinary technique incorporating areas such as pharmaceutical research, proteomics, polymer science, medicine, environmental chemistry, and recently archeology. This article aims to review recent developments in mass spectrometry methodologies in the identification of structural and spatial isomers in biological macromolecules, such as aspartic acid and isoaspartic acid (Asp/IsoAsp), leucine and isoleucine (Leu/Ile), glutamic acid and γ‐glutamic acid, and D/L enantiomers. © 2012 Wiley Periodicals, Inc. Mass Spec Rev 31:609–625, 2012
On the Generalised Stretch Function
Authors: Kharlamov Alexander A. , Filip Petr
Published: February 2012

The tube theory represents a powerful tool for the description of polymer behaviour. In this theory, the term in the form of an integral over a full solid angle of a magnitude of deformed unit vector represents the stretch function. This term relates the lengths of the random walk of a molecule in deformed and undeformed states. For the case of the Doi‐Edwards model, the integrand is raised to a power of one, however, for other models the power differs from one. The aim of this contribution is to derive an analytical algebraic approximation of a general form of this integral with the integrand raised to an arbitrary power within the physically justified interval between zero and two.

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CDC4/FBXW7 and the ‘just enough’ model of tumourigenesis
Authors: Davis Hayley , Tomlinson Ian
Published: February 2012

There is good evidence to show that cancer‐causing mutations are not always simple gain‐ and loss‐of‐function changes. One example is the APC gene, where the combination of mutations produces a ‘just‐right’ level of Wnt signalling. A recent article by Berger and colleagues posited a ‘continuum model’ in which increasing or decreasing gene expression of function was linearly associated with tumourigenesis. Berger also proposed an ‘obligate haploinsufficiency’ or ‘fail‐safe’ model, whereby heterozygous mutations produce sufficient derangement for tumourigenesis, yet homozygous mutations are cell‐lethal or senescence‐causing. One gene highlighted by Berger and colleagues as an example of a gene following a ‘continuum’ or ‘fail‐safe’ model was FBXW7/CDC4, a gene mutated in several different types of malignancy. We have analysed the COSMIC FBXW7 data. FBXW7 does not obviously follow a ‘continuum’ or ‘fail‐safe’ model and the most common mutant genotypes are mono‐allelic missense changes that affect critical arginine residues involved in interactions with substrates. There is no strong selection for complete loss of FBXW7 protein function, but bi‐allelic inactivating mutations do occur. For FBXW7, we suggest a variant of ‘just right’ which we call ‘just enough’. For FBXW7 mutations that occur away from the propellor tips, the heterozygote may have some effect on tumourigenesis, but there is selective pressure for a ‘second hit’. For propellor tip mutations, by contrast, there is weak pressure for a ‘second hit’ because they usually provide sufficient functional derangement on their own. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Estimate of deaths due to valvular insufficiency attributable to the use of benfluorex in France
Authors: Fournier Agnès , Zureik Mahmoud
Published: February 2012

Purpose

To estimate the number of deaths from valvular insufficiency caused by the use of the fenfluramine‐derivative benfluorex during the period 1976–2009 in France.

Methods

Our calculation was based on (i) the exposure level to benfluorex in the French population, derived from sales figures for the period 1976–2009 and from the main characteristics of benfluorex use provided by the French health products safety agency; (ii) the relative risk of hospitalization for valvular insufficiency among exposed compared with unexposed individuals with diabetes, originating from a cohort study based on a French medico‐administrative database, with benfluorex exposure assessed in 2006; (iii) the incidence of hospitalization for valvular insufficiency among exposed individuals, originating from the same database; and (iv) the mortality associated with valvular heart disease.

Results

In France, use of benfluorex during the period 1976–2009 is likely to be responsible for around 3100 hospitalizations and 1300 deaths due to valvular insufficiency. These figures may be underestimations.

Conclusions

The grave consequences benfluorex use have had for many people lend support to the public investigation, which has been set to understand the reasons that have contributed to the delay in withdrawing benfluorex from the French market. Copyright © 2012 John Wiley & Sons, Ltd.
Specific energy consumption of PV reverse osmosis systems. Experiment and theory
Authors: Fraidenraich N. , Vilela O. C. , Lima G. A.
Published: February 2012

Reverse osmosis equipment (RO), driven by photovoltaic systems, can be a reliable way to provide drinking water for the population of remote areas. The specific energy consumption (SEC) of an RO equipment is an important parameter to evaluate the equipment quality and its operating conditions. In this paper, we describe a theoretical study of the SEC of an RO equipment. It is briefly analyzed the SEC for ideal systems. Then, we obtain analytic expressions for real systems, operating under variable conditions. Finally, a limiting case, when the applied pressure is equal to the transmembrane pressure at the output of the equipment, is analyzed. An experimental study of a PV‐RO equipment conducted on a commercial multistage desalination unit over a broad range of operating conditions is described. A variable speed drive couples the PV generator to the RO system. Experimental results obtained for the system present a minimum (SEC) lying in a range of (R) between 0.2 and 0.4, smaller than the value obtained for the limiting case (approximately 0.5). The minimum values obtained for hydraulic (SEC) are around 0.32 kWh m‐3 for 2,000 mg L‐1 and 0.65 kWh m‐3 for 5,000 mg·L‐1. For the limiting case the minimum hydraulic SEC are 0.18 kWh m‐3 and 0.47 kWh m‐3, respectively (R = 0.5). A good agreement is found between predicted and measured results. The proposed procedure for calculating (SEC) is simple, precise and general, yielding a valuable tool to evaluate whether the region of operation of a PV‐RO system is adequate, according to the main aim of reducing water costs. Copyright © 2012 John Wiley & Sons, Ltd.
The mysterious RAMP proteins and their roles in small RNA‐based immunity
Authors: Wang Ruiying , Li Hong
Published: February 2012

A new class of prokaryotic RNA binding proteins called Repeat Associated Mysterious Proteins (RAMPs), has recently been identified. These proteins play key roles in a novel type immunity in which the DNA of the host organism (e.g. a prokaryote) has sequence segments corresponding to the sequences of potential viral invaders. The sequences embedded in the host DNA confer immunity by directing selective destruction of the nucleic acid of the virus using an RNA‐based strategy. In this viral defense mechanism, RAMP proteins have multiple functional roles including endoribonucleotic cleavage and ribonucleoprotein particle assembly. RAMPs contain the classical RNA recognition motif (RRM), often in tandem, and a conserved glycine‐rich segment (G‐loop) near the carboxyl terminus. However, unlike RRMs that bind single‐stranded RNA using their β‐sheet surface, RAMPs make use of both sides of the RRM fold and interact with both single‐stranded and structured RNA. The unique spatial arrangement of the two RRM folds, facilitated by a hallmark G‐loop, is crucial to formation of a composite surface for recognition of specific RNA. Evidence for RNA‐dependent oligomerization is also observed in some RAMP proteins that may serve as an important strategy to increase specificity.
The third‐order optical nonlinearity of Bi1.5Zn1.0Nb1.5O7 thin film on quartz by pulsed laser deposition
Authors: Yang Guohua , Han Junhe , Huo Zhuoyu , Nie Yangzhou , Gu Yuzong
Published: February 2012

Bi1.5Zn1.0Nb1.5O7 (BZN) thin films with good surface morphology were prepared on fused quartz substrates by pulsed laser deposition (PLD). The X‐ray diffraction (XRD) analysis and atomic force microscope (AFM) surface morphology measurements were performed on the samples. The XRD pattern demonstrated that the films are cubic pyrochlore structure and well crystallized. The AFM analysis indicated that the films have less rough surface. The fundamental optical constants, such as band gap, the wavelength dependence of the transmittance, and the refractive index, were obtained. The sign and magnitude of both real and imaginary parts of third‐order nonlinear susceptibility χ(3) of the BZN thin films were determined by a single beam Z‐scan technique performed at 1064 nm with a picoseconds laser. The third‐order nonlinear refractive index coefficient γ and the nonlinear absorption coefficient β of the BZN thin films are 4.06 × 10−15 m2/W and −1.45 × 10−9 m/W, respectively. The real part and the imaginary part of the third‐order nonlinear susceptibility χ(3) of the BZN thin films are 6.03 × 10−9 and 1.82 × 10−10 esu, respectively. The mechanisms of nonlinear refraction and nonlinear absorption were discussed. The results suggest that BZN thin film exhibit large third‐order nonlinear optical properties and be a promising material for applications in nonlinear optical devices.
Effect of different annealing temperatures and SiO2/Si(100) substrate on the properties of nickel containing titania thin sol–gel films
Authors: Pärna Rainer , Joost Urmas , Nõmmiste Ergo , Käämbre Tanel , Kikas Arvo , Kuusik Ivar , Kink Ilmar , Hirsimäki Mika , Kisand Vambola
Published: February 2012

Nickel containing titania thin films have been prepared on SiO2/Si(100) substrate by using the sol–gel deposition and annealing in the air at 450–1150 °C. Several experimental techniques [atomic force microscopy (AFM), X‐ray diffraction (XRD), X‐ray reflection (XRR), Raman spectroscopy, energy dispersive X‐ray analysis (EDX), X‐ray photoelectron spectroscopy (XPS), X‐ray absorption spectroscopy (XAS), UV–Vis spectroscopy and hydrophilicity measurements] have been applied to characterize these films. Further, the results of this study were compared to previously investigated nickel containing titania on HF‐etched Si(100) (i.e. without oxide layer). The morphological and structural properties of nickel containing titania were found to be dependent on the kind of the substrate on which the films were prepared. The thin films deposited on SiO2/Si(100) substrate, compared to similar films on HF‐etched Si(100) substrate, were more uniform, did not contain large pores and had smaller RMS roughness, especially when annealed below 650 °C. Also films on SiO2/Si(100) substrate were more crystalline and anatase transformation to rutile phase occurred at 150 °C lower temperature. Nickel in the films appeared to be in the 2+ oxidation state. When films were annealed above 650 °C, nickel was found mainly in the NiTiO3 crystallites. Nickel compounds segregated to the surface of the film, forming islands. Nickel addition red‐shifted the titania fundamental absorption edge further into the visible range. Films on both substrates demonstrated couple of tens of nanometers thick interlayer formation (between films and substrates) after annealing at 850 and 900 °C. We demonstrated that a well‐crystallined anatase was crucial for obtaining a good light‐induced hydrophilic nickel containing titania surface.
Conditional negative association for competing urns
Authors: Kahn J. , Neiman M.
Published: February 2012

We prove conditional negative association for random variables xj = 1 (j∈[n]:= {1…n}) , where σ(1)…σ(m) are i.i.d. from [n]. (The σ(i) 's are thought of as the locations of balls dropped independently into urns 1…n according to some common distribution, so that, for some threshold tj, xj is the indicator of the event that at least tj balls land in urn j.) We mostly deal with the more general situation in which the σ(i) 's need not be identically distributed, proving results which imply conditional negative association in the i.i.d. case. Some of the results—particularly Lemma 8 on graph orientations—are thought to be of independent interest. We also give a counterexample to a negative correlation conjecture of D. Welsh, a strong version of a (still open) conjecture of G. Farr. © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 2012
Managing software development information in global configuration management activities
Authors: Capilla Rafael , Dueñas Juan C. , Krikhaar René
Published: February 2012

Software Configuration Management (SCM) techniques have been considered the entry point to rigorous software engineering, where multiple organizations cooperate in a decentralized mode to save resources, ensure the quality of the diversity of software products, and manage corporate information to get a better return of investment. The incessant trend of Global Software Development (GSD) and the complexity of implementing a correct SCM solution grow not only because of the changing circumstances, but also because of the interactions and the forces related to GSD activities. This paper addresses the role SCM plays in the development of commercial products and systems, and introduces a SCM reference model to describe the relationships between the different technical, organizational, and product concerns any software development company should support in the global market. © 2012 Wiley Periodicals, Inc. Syst Eng
Removal of Cd(II) from aqueous solution by using polyaniline/polystyrene nanocomposite
Authors: Taghipour Kolaei Zahra , Tanzifi Marjan , Yousefi Aliyeh , Eisazadeh Hossein
Published: February 2012

One of the suitable methods for removing heavy metals from water and waste water is the use of a surface adsorption process. In this study, polyaniline/polystyrene (PAn/PS) nanocomposite was prepared in aqueous solution by the polymerization of styrene and aniline using potassium iodate and ammonium peroxydisulfate as oxidants in the presence of surfactive dopant sodium dodecylbenzenesulfonate and poly(vinyl pyrrolidone) as surfactant. The capability of separating Cd(II) ions was studied, and the results were compared with those obtained with other adsorbents. The results indicated that removal percentage was increased by increasing the concentration of adsorbent, contact time, and the pH of the solution. J. VINYL ADDIT. TECHNOL.,, 2012. © 2012 Society of Plastics Engineers
Undersized (12.5 mm diameter) glass beads with minimal amount (11 mg) of geochemical and archeological silicic samples for X‐ray fluorescence determination of major oxides
Authors: Nakayama Kenichi , Nakamura Toshihiro
Published: February 2012

The small glass bead technique was developed to assay precious silicic samples for geochemical and archeological analyses. Undersized (12.5 mm diameter) glass beads were prepared for wavelength dispersive X‐ray fluorescence determination of major oxides (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, and total Fe2O3). Synthetic calibration standards were prepared by compounding chemical reagents (oxides, carbonates, and diphosphate). For reliable calibration, recipe compositions of standard specimens were constructed on the basis of the evenness of plot intervals on a calibration curve. Calibration curves showed good linearity (correlation coefficient: r > 0.998). Analytical results of major oxides in granitic and basaltic rocks, obsidian, and ancient pottery were obtained with good precision (relative standard deviations were the following: <3% for more than 10.0 mass% of analyte, <5% for 1.0–10.0 mass% of analyte, and <15% for 0.1–1.0 mass% of analyte). Lower limits of detection were roughly a sub‐percentage of analyte in an unprepared sample: 0.3 mass% for Na2O, 1.0 mass% for SiO2, 0.01 mass% for MnO, and so on. The present preparation reduced the following analytical scales: (1) amount of sample from 400 mg to 11 mg (97% cutting out), (2) amount of Li2B4O7 as an alkali flux from 4000 mg to 396 mg (90% cutting out), and (3) weight of platinum crucible from 80 g to 12.5 g (84% cutting out). This small‐scale preparation might enable us to conduct destructive pretreatment of valuable and limited silicic samples such as archeological ceramics and stone tools, geochemical minerals in rock, and sediments and sand. Copyright © 2012 John Wiley & Sons, Ltd.
Bound states in the mirror TBA
Authors: Arutyunov Gleb , Frolov Sergey , van Tongeren Stijn J.
Published: February 2012

Abstract

The spectrum of the light-cone AdS5×S5superstring contains states composed of particles with complex momenta including in particular those which turn into bound states in the decompactification limit. We propose the mirror TBA description for these states. We focus on a three-particle state which is a finite-size representative of a scattering state of a fundamental particle and a two-particle bound state and dual to an operator from the$ \mathfrak{s}\mathfrak{u}(2) $sector of$ \mathcal{N} = 4\;{\text{SYM}} $. We find that the analytic behavior of Y-functions differs drastically from the case of states with real momenta. Most importantly,YQ-functions exhibit poles in the analyticity strip which leads to the appearance of new terms in the formula for the energy of this state. In addition, the TBA equations are supplied by quantization conditions which involveY2. Considering yet another example of a three- particle state, we find that the corresponding quantization conditions do not even involveY1. Our treatment can be generalized to a wide class of states with complex momenta.
Nerve and Arterial Supply to the Hand in Vesalius's De Humani Corporis Fabrica
Authors: Denkler Keith , Norman Max Austin
Published: February 2012

Background Belgian anatomist Andreas Vesalius, in his groundbreaking medical atlas De Humani Corporis Fabrica, 1543, committed to paper two anatomical errors relating to the vascular and nervous system of the hand. In the diagrams, he depicts a highly irregular symmetrical sensory innervation of the median and ulnar nerves. He also fails to mention or illustrate the deep or superficial palmar arches.
Perspectives on faculty development: aiming for 6/6 by 2020
Authors: Steinert Yvonne
Published: February 2012

Faculty development has a key role to play in individual and organizational
development. This perspective on faculty development, which builds on the 2020 Vision of
Faculty Development Across the Medical Education Continuum Conference and the First
International Conference on Faculty Development in the Health Professions, describes six
recommendations that we should consider as the field of faculty development moves
forward: grounding faculty development in a theoretical framework; broadening the focus
of faculty development to address the various roles that clinicians and basic scientists
play; recognizing the role that faculty development can play in promoting curricular and
organizational change; expanding our notion of how faculty members develop and moving
beyond formal, structured activities to incorporate notions of work-based learning and
communities of practice; making faculty development an expectation for all faculty
members; and promoting scholarship in faculty development to ensure that research
informs practice. Looking ahead, we should also consider strategies for leading change,
collaborate across institutions and international borders, and work together to share
lessons learned in research and practice.
When Natural Experiments Are Neither Natural nor Experiments
Authors: SEKHON JASJEET S. , TITIUNIK ROCÍO
Published: February 2012

Natural experiments help to overcome some of the obstacles researchers face when making causal inferences in the social sciences. However, even when natural interventions are randomly assigned, some of the treatment–control comparisons made available by natural experiments may not be valid. We offer a framework for clarifying the issues involved, which are subtle and often overlooked. We illustrate our framework by examining four different natural experiments used in the literature. In each case, random assignment of the intervention is not sufficient to provide an unbiased estimate of the causal effect. Additional assumptions are required that are problematic. For some examples, we propose alternative research designs that avoid these conceptual difficulties.
Foucault's Turn From Phenomenology: Implications for Dance Studies
Authors: Ness Sally Ann
Published: February 2012

No critic of phenomenology, arguably, has been more influential in prefiguring recent discourses on power, gender, and sexuality that have emerged in dance studies in recent decades than the philosopher-historian-critic Michel Foucault. The number of dance scholars directly citing Foucault, and the number influenced indirectly by his ideas through intermediary theorists such as Judith Butler—perhaps the single most popular one—is so large as to require an essay of its own just to survey. Virtually every analysis of choreographic practice that has addressed these topics since the 1980s has drawn directly or indirectly on Foucault's theories. Indeed, the very mention of the term “discipline” in current dance scholarship (and many related fields as well) more or less automatically makes reference to Foucault's genealogical study of incarceration, Surveiller et punir. Naissance de la prison, translated into English as Discipline and Punish: Birth of the Prison, and, in particular to the chapter, “Les corps dociles” or “Docile Bodies” (Foucault 1975, 137–171; 1975/1995, 135–170).
Phenomenology and Dance: Husserlian Meditations
Authors: Pakes Anna
Published: February 2012

The dimming of the house lights focuses attention on the still darkened stage, although awareness of the others in the auditorium and its quieted bustle does not entirely fade. From the stage, the sound of several people taking five or six measured footsteps in unison, then stopping, momentarily precedes the lights (stage and house) fading quickly up to reveal nine performers. They stand, facing out, dressed in ordinary clothes (shirt and jacket, jumper and skirt, different colors), steady gaze directed at the audience. They stand in the gaps between a series of reflective slabs, each of the same regular dimensions, slightly wider and taller than the performers themselves. Behind the performers is a further line of panels cut from the same material. After a brief pause, the space darkens.
Mapping, localization and motion planning in mobile multi-robotic systems
Authors: Rone William , Ben-Tzvi Pinhas
Published: February 2012

As researchers have pushed the limits of what can be accomplished by a single robot operating in a known or unknown environment, a greater emphasis has been placed on the utilization of mobile multi-robotic systems to accomplish various objectives. In transitioning from a robot-centric approach to a system-centric approach, considerations must be made for the computational and communicative aspects of the group as a whole, in addition to electromechanical considerations of individual robots. This paper reviews the state-of-the-art of mobile multi-robotic system research, with an emphasis on the confluence of mapping, localization and motion control of robotic system. Methods that compose these three topics are presented, including areas of overlap, such as integrated exploration and simultaneous localization and mapping. From these methods, an analysis of benefits, challenges and tradeoffs associated with multi-robotic system design and use are presented. Finally, specific applications of multi-robotic systems are also addressed in various contexts.
Doubt, Knowledge and the Cogito in Descartes' Meditations
Authors: Watling John
Published: February 2012

Descartes published his Meditations in First Philosophy in 1641. A French translation from the original Latin, which he saw and approved, followed six years later. The words ‘in First Philosophy’ indicate that the Meditations attack fundamental questions, the chief of them being the nature of knowledge and the nature of man. I shall deal almost entirely with his treatment of the first, the nature of knowledge; even when the two questions become mixed up, as they notoriously do, I shall not encroach on to the second, the nature of man. The Meditations were intended to confirm Descartes' reputation as a philosopher (he was already pre-eminent as a mathematician and a scientist) and, to increase their impact, they were accompanied in their first publication by a series of comments solicited from notable theologians and philosophers together with Descartes' replies. These comments are called the Objections and numbered from one to six, but it is only an accident that there are six Meditations and six Objections. There are six Objections because there are six objectors (that is not quite true, the sixth Objection being a collection of comments from several people) and each Objection ranges over the whole work, although, of course, the different commentators focused upon the parts they found important or questionable. Many of the Objections, particularly those of Arnauld and Gassendi, contain acute and valuable criticisms. Descartes took exception to Gassendi's contribution and wished not to have it published. He maintained that Gassendi quite misunderstood him, but that doesn't seem true. It is true that Gassendi pokes fun at Descartes in addressing him first ‘O Soul’ and later, pretending to realize his mistake, ‘O Mind’, but no doubt the trouble was that Gassendi understood rather too well, fastening upon inconsequentialities in the argument and inconsistencies in the thought and finding, against both, formidable arguments. Inconsequentialities and inconsistencies there are, so much so that the work is a set of parts rested together to give the appearance of a construction, not fitted together really to make one. That did not prevent the Meditations having as great an influence on philosophical thought as any work from the day of its publication to our own, or prevent Descartes' ideas from occupying the minds of philosophers ever since.
Hume on Thought and Belief
Authors: Craig Edward
Published: February 2012

I. Two topics given prominence in the early sections of Hume's Enquiry Concerning Human Understanding are those of thought and belief. Of each Hume asks two questions. One, which we might call the constitutive question: what exactly is it to have a thought, or to hold a belief?—and another, which we may call the genetic question: how do we come by our thoughts, or our capacity to think them, and how do we come to believe that certain of these thoughts are true? In this lecture I shall be considering the detail of Hume's answers to these questions; but first I want to say a little about why they should have loomed large for him at all.
Hume on Liberty and Necessity
Authors: Vesey Godfrey
Published: February 2012

David Hume (1711–1776) described the question of liberty and necessity as ‘the most contentious question of metaphysics, the most contentious science’ (Hume [1748] 1975, p. 95). He was right about it being contentious. Whether it is metaphysical is another matter. I think that what is genuinely metaphysical is an assumption that Hume, and a good many other philosophers, make in their treatment of the question. The assumption is about language and reality. I call it ‘the conformity assumption’. But more about that shortly. Let us begin at the obvious beginning, by considering what the terms ‘liberty’ and ‘necessity’ mean in the expression ‘liberty and necessity’.
Hume's Philosophy of Religion
Authors: Flew Antony
Published: February 2012

I shall be dealing with not only Sections X and XI but also Part II of Section VIII and Part III of Section XII. Of all this material we have, anywhere in the originally anonymous and later emphatically disowned Treatise of Human Nature, Hume's first book, nothing more than at most hints. But in a surviving letter, written while he was still working on the manuscript of that Treatise, Hume wrote: ‘I am at present castrating my work, that is, cutting off its nobler parts; that is, endeavouring it shall give as little offence as possible, before which I would not pretend to put it in the Doctor's hands’. Enclosed with this letter were some ‘Reasonings concerning Miracles’, which must have anticipated what became Section X of our Enquiry. Presumably there were other excised anticipations also. The ‘Doctor’ mentioned was a Doctor of Theology, Joseph Butler, soon to be appointed Bishop of Durham; an office open in that period only to believing Christians.
Karl Marx and Friedrich Engels
Authors: Arthur C. J.
Published: February 2012

Karl Marx (1818–1883) was born in Trèves in the Rhineland. He studied law in Bonn, philosophy and history in Berlin, and received a doctorate from the University of Jena for a thesis on Epicurus (341–270 BC). (Epicurus' philosophy was a reaction against the ‘other-worldliness’ of Plato's theory of Forms. Whereas for Plato knowledge was of intelligible Forms, and the criterion of the truth of a hypothesis about the definition of a Form was that it should survive a Socratic testing by question and answer, for Epicurus the criterion of truth was sensation, and employment of this criterion favoured the theory with which Plato explicitly contrasted the theory of Forms (Sophist 246a–d), namely, the materialism of the atomists, Leucippus and Democritus.) Marx was editor of the Rheinische Zeitung of Cologne, 1842–1843. The paper was suppressed and he moved to Paris, becoming co-editor of the Deutsch-französische Jahrbücher, the one and only issue of which contained two articles by Marx and two by his friend, Friedrich Engels (1829–1895). Together they wrote The German Ideology (1846) and their most influential work, The Communist Manifesto (1848). Marx had been expelled from France in 1845, and went to Brussels, from where he was expelled during the 1848 revolutions. He went to Cologne to start, with Engels and others, a paper with a revolutionary editorial policy, the Neue Rheinische Zeitung. Expelled once again, Marx finally settled in London, working in the British Museum on his great historical analysis of capitalism, Das Kapital. The first volume was published in 1867, the remaining two volumes, completed by Engels after Marx's death, in 1885 and 1895.
Bertrand Arthur William Russell
Authors: Sainsbury R. M.
Published: February 2012

Bertrand Russell (1872–1970), born in Trelleck, Wales, was the grandson of the first Earl Russell, who introduced the Reform Bill of 1832 and served as prime minister under Queen Victoria. He studied mathematics and philosophy at Trinity College, Cambridge, 1890–1894, was a Fellow of Trinity College, 1895–1901, a Fellow of the Royal Society in 1908, and was a lecturer in philosophy, 1910–1916. Among his publications in philosophy in this period were An Essay on the Foundations of Geometry (1897), A Critical Exposition of the Philosophy of Leibniz (1900), The Principles of Mathematics (1903), Principia Mathematica (with A. N. Whitehead, 1910–1913), The Problems of Philosophy (1912) and Our Knowledge of the External World (1914).
Ayer, Language, Truth and Logic
Authors: Hanfling Oswald
Published: February 2012

When, in 1979, A. J. Ayer was asked for an evaluation of his youthful Language, Truth and Logic (LTL), he replied: ‘I suppose the most important of the defects was that nearly all of it was false’. Like many of the claims in the book itself, this verdict is open to question. What was wrong with LTL was not so much that what it said was false, but that it presented philosophical issues in an excessively simple and aggressive way. Yet it was just this quality that put the book and its author on the philosophical map, ensuring for them an important place in the history of twentieth-century philosophy. LTL presented a challenge to traditional ways of doing philosophy, the reverberations of which are still evident today.
First language attrition in the speech of Dutch–English bilinguals: The case of monozygotic twin sisters
Authors: MAYR ROBERT , PRICE SACHA , MENNEN INEKE
Published: February 2012

Recent years have seen a proliferation of research on attrition in L1 speech (de Leeuw, Mennen & Scobbie, in press; de Leeuw, Schmid & Mennen, 2010; Dmitrieva, Jongman & Sereno, 2010; Mennen, 2004). Adding to this line of inquiry, the present study investigates the speech of a 62-year-old bilingual monozygotic twin who emigrated to an L2-speaking environment 30 years ago. Changes in L1 accent were assessed by comparing her speech to that of her identical twin sister who remained in the L1-speaking environment, thus providing a unique control setting. Acoustic analyses of voice onset time and vowels indicate pervasive changes to the emigrated twin's L1 accent, with attrition presenting in the form of cross-linguistic assimilation patterns. Interestingly, her L1 vowel space exhibited a systematic increase in first formant frequency, confirming claims that L1 and L2 sounds may be related to each other at a system-wide level (Chang, 2010, 2011; Guion, 2003). Implications for theoretical models of bilingual sound systems are discussed.
Relationship between interplanetary parameters and the magnetopause reconnection rate quantified from observations of the expanding polar cap
Authors: Milan S. E. , Gosling J. S. , Hubert B.
Published: February 2012

Many studies have attempted to quantify the coupling of energy from the solar wind into the magnetosphere. In this paper we parameterize the dependence of the magnetopause reconnection rate on interplanetary parameters from the OMNI data set. The reconnection rate is measured as the rate of expansion of the polar cap during periods when the nightside reconnection rate is thought to be low, determined from observations by the Imager for Magnetopause‐to‐Aurora Global Exploration (IMAGE) Far Ultraviolet (FUV) imager. Our fitting suggests that the reconnection rate is determined by the magnetic flux transport in the solar wind across a channel approximately 4 RE in width, with a small correction dependent on the solar wind speed, and a clock angle dependence. The reconnection rate is not found to be significantly dependent on the solar wind density. Comparison of the modeled reconnection rate with SuperDARN measurements of the cross‐polar cap potential provides broad support for the magnitude of the predictions. In the course of the paper we discuss the relationship between the dayside reconnection rate and the cross‐polar cap potential.
Seismic structure near the inner core boundary in the south polar region
Authors: Ohtaki Toshiki , Kaneshima Satoshi , Kanjo Kenji
Published: February 2012

It is crucial to obtain good spatial coverage of seismic data points for better understanding the Earth's core, but the core beneath the polar regions remains largely unexplored. We analyzed differential traveltimes and amplitude ratios of core phases whose raypaths run beneath Antarctica for determining the Vp and Qp structure near the inner core boundary in the south polar region. The model we obtained (south polar region model, SPR) is described relative to the preliminary reference Earth model (PREM) as follows: a 0.05 km/s lower Vp value at the top of the inner core, a 1.5 times steeper Vp gradient in the upper 300 km of the inner core, a smaller Qp (300) in the upper 300 km of the inner core, and a 0.04 km/s lower Vp at the bottom of the outer core. The Vp values of SPR in the lowermost outer core lie between those of PREM and AK135, being closer to those of AK135. The lowermost outer core Vp inside the tangent cylinder is thus close to the global average. In the upper inner core, SPR has lower Vp than AK135 and PREM. The SPR Vp profile is close to that of previous models for the Western Hemisphere, although most of our data sample the Eastern Hemisphere of the inner core. Our results indicate that the inner core does not have a simple hemispherical variation as usually supposed. Our data support an eyeball‐shaped high‐Vp anomaly with compressional velocity higher than in 1‐D reference Earth models, concentrated to a smaller region beneath eastern Asia.
Estimating effective particle size of tropical deep convective clouds with a look‐up table method using satellite measurements of brightness temperature differences
Authors: Hong Gang , Minnis Patrick , Doelling David , Ayers J. Kirk , Sun‐Mack Szedung
Published: February 2012

A method for estimating effective ice particle radius Re at the tops of tropical deep convective clouds (DCC) is developed on the basis of precomputed look‐up tables (LUTs) of brightness temperature differences (BTDs) between the 3.7 and 11.0 μm bands. A combination of discrete ordinates radiative transfer and correlated k distribution programs, which account for the multiple scattering and monochromatic molecular absorption in the atmosphere, is utilized to compute the LUTs as functions of solar zenith angle, satellite zenith angle, relative azimuth angle, Re, cloud top temperature (CTT), and cloud visible optical thickness τ. The LUT‐estimated DCC Re agrees well with the cloud retrievals of the Moderate Resolution Imaging Spectroradiometer (MODIS) for the NASA Clouds and Earth's Radiant Energy System with a correlation coefficient of 0.988 and differences of less than 10%. The LUTs are applied to 1 year of measurements taken from MODIS aboard Aqua in 2007 to estimate DCC Re and are compared to a similar quantity from CloudSat over the region bounded by 140°E, 180°E, 0°N, and 20°N in the Western Pacific Warm Pool. The estimated DCC Re values are mainly concentrated in the range of 25–45 μm and decrease with CTT. Matching the LUT‐estimated Re with ice cloud Re retrieved by CloudSat, it is found that the ice cloud τ values from DCC top to the vertical location where LUT‐estimated Re is located at the CloudSat‐retrieved Re profile are mostly less than 2.5 with a mean value of about 1.3. Changes in the DCC τ can result in differences of less than 10% for Re estimated from LUTs. The LUTs of 0.65 μm bidirectional reflectance distribution function (BRDF) are built as functions of viewing geometry and column amount of ozone above upper troposphere. The 0.65 μm BRDF can eliminate some noncore portions of the DCCs detected using only 11 μm brightness temperature thresholds, which result in a mean difference of only 0.6 μm for DCC Re estimated from BTD LUTs.
Antarctic Isotope Maxima events 24 and 25 identified in benthic marine δ18O
Authors: Caballero‐Gill Rocio P. , Clemens Steve , Prell Warren
Published: February 2012

High‐resolution planktic and benthic δ18O records at Site 1146 (northern South China Sea) include structure within Marine Isotope Stage 5.4, 118.5–105.9 ka, that is not captured in stacked δ18O records commonly used for age model construction and as proxies for global ice volume. Leveraging a common monsoonal influence, Site 1146 planktic δ18O was aligned to speleothem δ18O from southeastern China to derive a radiometrically calibrated (RC) age model. On the RC age model, the benthic δ18O record contains structure equivalent in time to Antarctic Isotope Maximum (AIM) events 24 and 25. Sea level reconstructions for isotopic event 5.4 suggest that these benthic δ18O events (AIM 24 and 25) derive from isotopic change (ice volume) although some temperature change cannot be completely excluded.
Young Adults' Performance in a Low‐Intensity Weight Loss Campaign
Authors: LaRose Jessica Gokee , Leahey Tricia M. , Weinberg Brad M. , Kumar Rajiv , Wing Rena R.
Published: February 2012

Young adults (YA) are underrepresented in behavioral weight loss programs and achieve poorer outcomes than older adults (OA). There has been a call to develop programs specifically targeting this age group. This study examined the performance of YA enrolled in a low‐intensity, team‐based weight loss campaign and compared their outcomes to OA to determine the utility of such an approach for weight loss in this population. Shape Up Rhode Island (SURI) 2009 was a 12‐week online team‐based weight loss and exercise competition (N = 6,795, 81% female, 94% white, age = 44.7 ± 11.2, BMI = 29.4 ± 5.9). YA was defined as 18–35 years and OA as >35 years; YA and OA were compared on enrollment, retention, weight loss, and change in steps. A total of 1,562 YA enrolled and 715 completed the program. Fewer YA completed compared with OA (46 vs. 62%, P < 0.001). However, among completers, YA achieved greater percent weight loss (‐4.5 ± 4.0 vs. −3.8 ± 3.2%) and greater daily step change (+1,578.2 ± 3,877.2 vs. +1,342.2 ± 3,645.7) than OA (P's < 0.001). Further, more YA completers achieved a ≥5% weight loss (40 vs. 29%, P < 0.001). Findings were consistent in the overweight/obese (OW/OB) subsample, and using ≤25 years of age as the cut off for YA. Weight losses among YA in this low‐intensity weight loss campaign were quite promising, with over 700 YA completing the program and on average achieving a 4.5% weight loss. Indeed, the potential public health impact of such an approach is substantial; future efforts to develop programs for this age group may benefit from using a low‐intensity, team‐based approach.
Adropin Deficiency Is Associated With Increased Adiposity and Insulin Resistance
Authors: Ganesh‐Kumar K. , Zhang Jingying , Gao Su , Rossi Jari , McGuinness Owen P. , Halem Heather H. , Culler Michael D. , Mynatt Randall L. , Butler Andrew A.
Published: February 2012

Adropin is a secreted peptide that improves hepatic steatosis and glucose homeostasis when administered to diet‐induced obese mice. It is not clear if adropin is a peptide hormone regulated by signals of metabolic state. Moreover, the significance of a decline in adropin expression with obesity with respect to metabolic disease is also not clear. We investigated the regulation of serum adropin by metabolic status and diet. Serum adropin levels were high in chow‐fed conditions and were suppressed by fasting and diet‐induced obesity (DIO). High adropin levels were observed in mice fed a high‐fat low carbohydrate diet, whereas lower levels were observed in mice fed a low‐fat high carbohydrate diet. To investigate the role of adropin deficiency in metabolic homeostasis, we generated adropin knockout mice (AdrKO) on the C57BL/6J background. AdrKO displayed a 50%‐increase in increase in adiposity, although food intake and energy expenditure were normal. AdrKO also exhibited dyslipidemia and impaired suppression of endogenous glucose production (EndoRa) in hyperinsulinemic‐euglycemic clamp conditions, suggesting insulin resistance. While homo‐ and heterozygous carriers of the null adropin allele exhibited normal DIO relative to controls, impaired glucose tolerance associated with weight gain was more severe in both groups. In summary, adropin is a peptide hormone regulated by fasting and feeding. In fed conditions, adropin levels are regulated dietary macronutrients, and increase with dietary fat content. Adropin is not required for regulating food intake, however, its functions impact on adiposity and are involved in preventing insulin resistance, dyslipidemia, and impaired glucose tolerance.