bluuebunny/crossref_metadata_2025 huggingface dataset:
Zur erforderlichen Größe von Zinkdurchlauföffnungen feuerverzinkter Hohlprofilkonstruktionen
Authors: Feldmann Markus , Schäfer Dirk
Published: April 2011

Ein Element zur Vermeidung von Verzug und Rissbildung beim Feuerverzinken ist die Wahl einer möglichst großen Eintauchgeschwindigkeit. Deswegen wurde hierfür ein Mindestwert von vE ≥ 0,8 m/min in der neuen DASt‐Ri 022 vorgeschrieben. Insbesondere bei Hohlprofilkonstruktionen hängt die Einhaltung dieses Mindestwertes stark von Größe und Anzahl der Zinkdurchlauföffnungen ab; und es hat sich herausgestellt, dass die bisherigen Regelungen zur Größe und Anordnung dieser Öffnungen nicht ausreichen. Hier setzt das Ziel der vorgestellten Untersuchungen an, nämlich Regeln für Art und Größe von Zinkdurchlauföffnungen zu entwickeln, die eine ausreichend große Eintauchgeschwindigkeit zur Vermeidung exzessiver Spannungs‐Dehnungszustände als Mitverursacher von Verzug und Rissbildung gewährleisten. Die Herleitungen bauen auf den Gesetzen der Hydraulik auf und werden mit Versuchen erprobt. Ergebnis ist ein einfacher und nachvollziehbarer Algorithmus zur Bestimmung von Größe und Verteilung von Zinkdurchlauföffnungen in Hohlprofilkonstruktionen, die auf die Vermeidung von Verzug und Rissbildung wie auch auf einen schnelleren Verzinkungsvorgang ausgerichtet sind. Daraus wird ein Bemessungsvorschlag in Form einer einfachen Tabelle abgeleitet.

Required Size of ventilation openings of hot‐dip galvanized hollow sections. In order to avoid distortion and cracking during hotdip galvanizing a relatively high immersion speed should be chosen. For instance, in the new German standard to avoid cracking during hot‐dip galvanizing DASt‐Ri 022 a dipping speed of vE ≥ 0,8 m/min has been proposed. Especially for elements with hollow sections the dipping speed is strongly dependant on the size of the ventilation openings. However, it was found that the current rules on size and distribution of these openings are not sufficient. Therefore, the aim of the research described hereafter was to find out rules for size and distribution of ventilation openings that enable a safe galvanizing by providing enough freedom for a quick immersion. Basis of the derivations are the rules of hydraulics that furthermore are verified by experiments of the immersion of hollow sections. The results yield into a simple and reasonable algorithm to determine size and distribution of ventilation openings of hollow sections, contributing to a distortion‐ and crack‐free structure. Finally a proposal in form of design a sheet is made available.
Support vector machine‐based equalisation for direct‐sequence ultra wideband systems
Authors: Musbah Mohamed , Zhu Xu
Published: April 2011

We proposed the support vector machine (SVM)‐based equalisation schemes for direct‐sequence ultra wideband (UWB) systems. The severe intersymbol interference caused by the UWB channel was formulated as a pattern classification problem in the SVM‐based equaliser, which operates in two main modes: training and detection. We also applied the least squares support vector classifiers (LS‐SVCs) to reduce the training complexity and sparse LS‐SVCs to reduce the detection complexity, with little performance loss compared to SVCs. Simulation results confirm the outperformance of the proposed equalisers over the conventional rake receiver with the same order of complexity for detection, especially when no channel information is known at the receiver. Also, the SVM‐based equalisers in the line‐of‐sight scenario provide a performance close to the case with additive white Gaussian noise only. Copyright © 2011 John Wiley & Sons, Ltd.
Pathways, networks, and systems medicine—the meeting place of the Aegean and the mind
Authors: Subramaniam Shankar , Nadeau Joseph H.
Published: April 2011

This article is categorized under:

Translational, Genomic, and Systems Medicine > Translational Medicine
Robotic‐Assisted Surgery and the Need for Standardized Pathways and Clinical Guidelines
Authors: Walters Linda , Eley Susan
Published: April 2011

Robotic surgical techniques are revolutionizing the way surgery is performed in an effort to improve patient outcomes. Although current literature is limited, studies have shown that patients who undergo robotic‐assisted procedures experience reduced surgical time, scarring, blood loss, pain, infection rates, and lengths of stay compared with patients who undergo open or laparoscopic procedures. Currently, start‐up costs for robotic systems are high and include the major equipment purchase as well as supplemental equipment purchases and staff member training. There is a need to develop standardized perioperative procedures or clinical guidelines that define optimal application of robotic‐assisted surgery to ensure a standard of care that is consistent across procedures and operators. Implementing a clinical pathway or guideline that is guided by evidence‐based practice will involve change. Lewin's 1947 basic change theory and the Marker umbrella model may be of use to help facilitate change.
Simple Solutions for Reducing First‐Procedure Delays
Authors: Fezza Maria , Palermo Gina Bledsoe
Published: April 2011

First‐procedure delays in the OR result in loss of revenue and subsequent procedure delays for patients, staff members, and other surgeons. Members of a committee at New York University Medical Hospital determined that the major cause of the delays in the OR was late arrival of surgeons, and they developed a plan to reduce first‐procedure delays in the OR through a physician accountability initiative. Committee members attempted to modify surgeon behavior by requiring the documentation of surgeons' arrival times and by reporting their daily attendance time. They sent daily e‐mail reminders asking surgeons with scheduled procedures to arrive 20 minutes before the procedure. This resulted in a 13% decrease in first‐procedure delays within two weeks and improvement continued. Overall, the plan improved first‐procedure delays from an initial on‐time start rate of 24% to 80%.
Critical Thinking and Clinical Judgment
Authors: Edel Elizabeth Morell
Published: April 2011

Critical Thinking and Clinical Judgment Rosalinda Alfaro‐LeFevre 4th edition 2009, Saunders Elsevier 308 pages, $46.95 softcover
AUTOMATIC CONTINUITY OF n-HOMOMORPHISMS BETWEEN TOPOLOGICAL ALGEBRAS
Authors: HONARY TAHER G. , SHAYANPOUR H.
Published: April 2011

A map θ:A→B between algebras A and B is called n-multiplicative if θ(a1a2⋯an)=θ(a1) θ(a2)⋯θ(an) for all elements a1,a2,…,an∈A. If θ is also linear then it is called an n-homomorphism. This notion is an extension of a homomorphism. We obtain some results on automatic continuity of n-homomorphisms between certain topological algebras, as well as Banach algebras. The main results are extensions of Johnson’s theorem to surjective n-homomorphisms on topological algebras, a theorem due to C. E. Rickart in 1950 to dense range n-homomorphisms on topological algebras and two theorems due to E. Park and J. Trout in 2009 to * -preserving n-homomorphisms on lmc * -algebras.
INDECOMPOSABLE REPRESENTATIONS OF THE EUCLIDEAN ALGEBRA 𝔢(3) FROM IRREDUCIBLE REPRESENTATIONS OF
Authors: DOUGLAS ANDREW , REPKA JOE
Published: April 2011

The Euclidean group E(3) is the noncompact, semidirect product group E(3)≅ℝ3⋊SO(3). It is the Lie group of orientation-preserving isometries of three-dimensional Euclidean space. The Euclidean algebra 𝔢(3) is the complexification of the Lie algebra of E(3). We embed the Euclidean algebra 𝔢(3) into the simple Lie algebra $\mathfrak {sl}(4,\mathbb {C})$ and show that the irreducible representations V (m,0,0) and V (0,0,m) of $\mathfrak {sl}(4,\mathbb {C})$ are 𝔢(3)-indecomposable, thus creating a new class of indecomposable 𝔢(3) -modules. We then show that V (0,m,0) may decompose.
COHERENT STATES IN BERNOULLI NOISE FUNCTIONALS
Authors: WANG CAISHI , HAN QI
Published: April 2011

Let (Ω,ℱ,ℙ) be a probability space and Z=(ZK)k∈ℕ a Bernoulli noise on (Ω,ℱ,ℙ) which has the chaotic representation property. In this paper, we investigate a special family of functionals of Z, which we call the coherent states. First, with the help of Z, we construct a mapping ϕ from l2(ℕ) to ℒ2(Ω,ℱ,ℙ) which is called the coherent mapping. We prove that ϕ has the continuity property and other properties of operation. We then define functionals of the form ϕ(f) with f∈l2 (ℕ) as the coherent states and prove that all the coherent states are total in ℒ2 (Ω,ℱ,ℙ) . We also show that ϕ can be used to factorize ℒ2 (Ω,ℱ,ℙ) . Finally we give an application of the coherent states to calculus of quantum Bernoulli noise.
A psychrotrophicBurkholderia cepaciastrain isolated from refrigerated raw milk showing proteolytic activity and adhesion to stainless steel
Authors: Nörnberg Maria de Fátima Barros Leal , Mentges Marilene Lenz , Silveira Silvana Terra , Tondo Eduardo César , Brandelli Adriano
Published: April 2011

The proteolytic activity of a psychrotrophic strain ofBurkholderia cepaciaisolated from refrigerated raw milk was characterized.Bur. cepaciaproduced proteolytic activity during growth at refrigeration temperature, with maximum activity at pH 6–7. The enzyme showed relative thermal stability in the range 40–50°C during 25 min, and maintained 80% its initial activity at 76°C/30 s. Milk coagulation assay showed that the crude protease fromBur. cepaciacaused coagulation from day 2 for skimmed milk, whereas coagulation was observed from day 5 for whole milk. The adherence of this strain to stainless steel was evaluated, and the substrata had around 107CFU/cm2after 15 to 60 min incubation. Results on biofilm development suggest that this bacterium could adhere and to form biofilms even at refrigeration temperatures. These results indicate thatBur. cepaciamay represent a potential hazardous to milk and dairy products.
Challenging the Economic Reform Paradigm: Policy and Politics in the Early 1980s' Collapse of the Rural Co-operative Medical System
Authors: Duckett Jane
Published: April 2011

Over the last two decades an economic reform paradigm has dominated social security and health research: economic reform policies have defined its parameters, established its premises, generated its questions and even furnished its answers. This paradigm has been particularly influential in accounts of the early 1980s' collapse of China's rural co-operative medical system (CMS), which is depicted almost exclusively as the outcome of the post-Mao economic policies that decollectivized agriculture. This article draws primarily on government documents and newspaper reports from the late 1970s and early 1980s to argue that CMS collapse is better explained by a change in health policy. It shows that this policy change was in turn shaped both by post-Mao elite politics and by CMS institutions dating back to the late 1960s. The article concludes by discussing how an explanation of CMS collapse that is centred on health policy and politics reveals the limitations of the economic reform paradigm and contributes to a fuller understanding of the post-Mao period.
The Local Environmental State in China: A Study of County-Level Cities in Suzhou
Authors: Li Yu-wai , Miao Bo , Lang Graeme
Published: April 2011

Local administration in China remains a contested territory of environmental governance. Economic growth often comes with high environmental cost; the central government's environmental regulations are implemented unevenly. This article examines the experience of policy uptake and adoption of the National Model City of Environmental Protection programme in the county-level cities of the Suzhou Municipality. It analyses the rationales for these cities' adoption of the policy, and implications for the emergence of the “environmental state” in local China. It suggests that while economic development remains an important priority of local officials, this preference is not immutable and is now complemented in some areas by substantial local commitments to environmental good practice, often under the influence of local leaders as well as provincial authorities.
Preparing the People for Mass Clemency: The 1956 Japanese War Crimes Trials in Shenyang and Taiyuan
Authors: Jacobs Justin
Published: April 2011

The lack of official government attention to Japanese war crimes during the Mao years has been widely acknowledged. Yet in the summer of 1956, years of preparatory work by Zhou Enlai culminated in the little-known and summarily dismissed trials of 1,062 self-confessed Japanese war criminals in Shenyang and Taiyuan. The extraordinarily lenient sentences given to 45 of the worst offenders – and wholesale pardons of 1,017 – were prompted by larger geopolitical considerations that effectively hamstrung PRC authorities from bringing the trials into closer alignment with previous ones in Europe and Japan. Zhou's determination to adopt a “policy of leniency” towards the Japanese prisoners, however, was sorely at odds with the sentiments of the general public. The need to prepare the people for a counterintuitive mass clemency saw a sudden and drastic shift in media discourse in 1954, followed by a series of remarkable cultural and intellectual campaigns that were designed to persuade the Chinese people that they should henceforth let bygones be bygones.
HES PRESIDENTIAL ADDRESS: THE COASE THEOREM LESSONS FOR THE STUDY OF THE HISTORY OF ECONOMIC THOUGHT
Authors: MEDEMA STEVEN G.
Published: April 2011

The Coase theorem has occupied a prominent place in economic discourse for the last half-century. The debate over the theorem and the uses to which it has been put are important moments in the history of modern economics, and the analysis of them by the historians of economics sheds light on certain of the tensions in contemporary historiography. This article discusses several aspects of the intellectual history of the Coase theorem, arguing that the study of this history illustrates the necessity of a pluralistic approach, and that attempts to write history from a singular historiographic perspective leave us with histories that are both misleading and incomplete.
CRISES AS A DISEASE OF THE BODY POLITICK. A METAPHOR IN THE HISTORY OF NINETEENTH-CENTURY ECONOMICS
Authors: BESOMI DANIELE
Published: April 2011

This paper examines the use of the medical metaphor in the early theories of crises. It first considers the borrowing of medical terminology and generic references to disease, which, notwithstanding their relatively trivial character, illustrate how crises were originally conceived as disturbances (often of a political nature) to a naturally healthy system. Then it shows how a more specific metaphor, the fever of speculation, shifted the emphasis by treating prosperity as the diseased phase, to which crises are a remedy. The metaphor of the epidemic spreading of the disease introduced the theme of the cumulative character of both upswing and downswing, while the similitude with intermittent fevers accounted for the recurring nature of crises. Finally, the paper examines how the medical reflections on the causality of diseases contributed to the epistemology of crises theory, and reflects on the metaphysical shift accompanying the transition from the theories of crises to the theories of cycles.
Diachronic change: Early versus late acquisition
Authors: WEERMAN FRED
Published: April 2011

There is a long linguistic tradition in which language change is explained in terms of first language acquisition. In this tradition, children are considered to be the agents of language change, or at least the agents of changes in the underlying grammar. Since the early 1980s, this has been formulated in the (generative) terminology in terms of parameters set by children: whereas an older generation acquires one particular setting of a parameter (during childhood), a next generation of L1 children may set a parameter differently, based on the input of their parents, and this may lead to a different output. For obvious reasons this argumentation had to be built on theoretical rather than empirical work on language acquisition. There are no children acquiring Old English or Middle Dutch, and, in fact, the field of acquisition research was until recently much less developed and very often not focused on the type of facts that happened to play a role in discussions of language change.
Parametric variation in acquisition and diachronic change: A response to the commentaries
Authors: MEISEL JÜRGEN M.
Published: April 2011

The starting hypothesis of the keynote article (KA) is that language acquisition plays an essential role in processes leading to grammatical change. Consequently, a minimal requirement, to be met by explanations of diachronic change is that they rely on mechanisms which are operative in acquisition. The KA is therefore an appeal for interdisciplinary cooperation between historical linguistics and acquisition research.
ON THE LOOMIS–SIKORSKI THEOREM FOR MV-ALGEBRAS WITH INTERNAL STATE
Authors: DI NOLA A. , DVUREČENSKIJ A. , LETTIERI A.
Published: April 2011

In Flaminio and Montagna [‘An algebraic approach to states on MV-algebras’, in:Fuzzy Logic 2,Proc. 5th EUSFLAT Conference, Ostrava, 11–14 September 2007 (ed. V. Novák) (Universitas Ostraviensis, Ostrava, 2007), Vol. II, pp. 201–206; ‘MV-algebras with internal states and probabilistic fuzzy logic’,Internat. J. Approx. Reason.50(2009), 138–152], the authors introduced MV-algebras with an internal state, called state MV-algebras. (The letters MV stand for multi-valued.) In Di Nola and Dvurečenskij [‘State-morphism MV-algebras’,Ann. Pure Appl. Logic161(2009), 161–173], a stronger version of state MV-algebras, called state-morphism MV-algebras, was defined. In this paper, we present the Loomis–Sikorski theorem forσ-complete MV-algebras with aσ-complete state-morphism-operator, showing that every such MV-algebra is aσ-homomorphic image of a tribe of functions with an internal state induced by a function where all the MV-operations are defined by points.
GENERALIZED AMENABILITY PROPERTIES OF THE BEURLING ALGEBRAS
Authors: GHAHRAMANI F. , SAMEI E. , ZHANG YONG
Published: April 2011

We show that every one-codimensional closed two-sided ideal in a boundedly approximately contractible Banach algebra has a bounded approximate identity. We use this to give a complete characterization of bounded approximate contractibility of Beurling algebras associated to symmetric weights. We give a slight modification of a criterion for bounded approximate contractibility. We use our criterion to show that, for the quasi-SIN groups, in the presence of a certain growth condition on a weight, the associated Beurling algebra is boundedly approximately amenable if and only if it is boundedly approximately contractible. We show that approximate amenability of a Beurling algebra on an IN group necessitates the amenability of the group. Finally, we show that, for every locally compact abelian group, in the presence of a growth condition on the weight, 2n-weak amenability of the associated Beurling algebra is equivalent to every point-derivation vanishing at the augmentation character.
POSITIVE LAWS ON LARGE SETS OF GENERATORS: COUNTEREXAMPLES FOR INFINITELY GENERATED GROUPS
Authors: ACCIARRI CRISTINA , FERNÁNDEZ-ALCOBER GUSTAVO A.
Published: April 2011

Shumyatsky and the second author proved that if G is a finitely generated residually finite p-group satisfying a law, then, for almost all primes p, the fact that a normal and commutator-closed set of generators satisfies a positive law implies that the whole of G also satisfies a (possibly different) positive law. In this paper, we construct a counterexample showing that the hypothesis of finite generation of the group G cannot be dispensed with.
Comparing conventional and organic olive groves in central Greece: plant and bird diversity and abundance
Authors: Solomou Alexandra , Sfougaris Athanassios
Published: April 2011

The present study was conducted in Magnesia Prefecture, central Greece, during the period May–June 2007. It aimed at the comparison between conventional and certified organic olive groves with regard to olive and olive oil production, diversity of plants (herbaceous and woody) and diversity and abundance of avifauna. Correlations between variables within herbaceous plants (linear regression) and woody plants (Principal Component Analysis), and the role of integration time of olive groves to the organic system were investigated. Also, finding easily measurable parameters indicating high bird diversity levels within organic and conventional management systems was a main target of the study. According to our findings, neither edible olive yield nor olive oil yield showed significant differences between conventional and certified organic olive groves. There is an increasing trend for alpha and beta diversity of herbaceous plant species, woody plant beta diversity, density and cover of woody plants, and density of breeding birds in certified organic olive groves (10 years) in comparison with conventional ones. The effect of time since the adoption of organic procedures is very important and produces benefits for the biodiversity. In the total olive groves 15 insectivorous, six granivorous and three insectivorous/granivorous birds species were recorded. Nine bird species distinguished by Ward's hierarchical clustering were identified as typical (indicator value, IndVal>50%) of specific farming systems. Among them, the Eurasian jay, associated with the 10-year certified organic olive groves, and the common cuckoo, Orphean warbler and Red-backed shrike, associated with the 6-year certified organic olive groves, should be regarded as characteristic species (IndVal>70%). Conclusively, organic farming favors some aspects of diversity of herbaceous and woody plants of olive grove ecosystems. On the contrary, similar effects on breeding bird diversity and density were not clearly recorded. However, breeding bird density proved a good indicator of their richness.
Does war make states? Rentierism and the formation of states in the Middle East
Authors: Schwarz Rolf
Published: April 2011

The famous dictum that ‘war makes states’ has received renewed interest with the experience of state failure and state collapse in many parts of the Developing World. Historical studies have shown that the activity of war-making was an essential ingredient of the process of state-making in early modern Europe. The history of state-making in the Arab Middle East shows that rentier states defy the ‘war makes states’ theory. This article compares four states from the Arab world, two having been exposed to the experience of war-making (Iraq and Jordan) and two not (the United Arab Emirates and Tunisia). The comparison of these four states shows that rentierism serves as an obstacle to the formation of legitimate and institutionalized states. However, the availability of external rents also allows state institutions and patronage channels to continue providing general welfare. Thus, rentierism produces a twin phenomenon of state weakness and life support for potentially failed states. It is only when war-making is employed in rentier states as a strategy of state-making that states fail and break.
Mechanical requirement and influence on the design and manufacturing of beam position monitor of Taiwan photon source
Authors: Hsueh H. P. , Huang I. T. , Chang C. C. , Hsu S. N. , Hsiung G. Y. , Chen J. R.
Published: April 2011

The beam position monitors (BPMs) with submicron-level resolution act as the major eyes of storage ring in detecting the position of electron beams and are used for feedback system to guide the beam orbit to the desired track. Compared to major improvements on backend electronics, the physical devices generate and transmit signals had little improvement due to the lack of control on manufacturing processes including all mechanical tolerance requirements. The design started with ANSYS to simulate mechanical deformation. Due to the small size (submillimetre) and complicated assembly of feedthrough structure, it is difficult to achieve 1 % tolerance (submicron) in all aspects including machining and brazing. The smallest tolerance for machining is 5 µ and the overall tolerance will be 30 µm. The influence of the tolerance on mechanical will be shown on time-domain reflectometry measurement. The resulted heat-related issue will also be discussed and addressed since the problem happened at SLAC (private communication with Albert Sheng at Stanford Linear Accelerator Center) and DIAMOND (presented at the RF Button Heating Mini-Workshop at EPAC 2008). Manufacturing steps will be described. The consequence of mismatch on manufacturing will be discussed. All related measurement and simulation data are presented in this paper.
Analytical and observational relations between landslide volume and surface area
Authors: Klar A. , Aharonov E. , Kalderon‐Asael B. , Katz O.
Published: April 2011

A remarkable field observation is that landslides of different sizes, from different locations around the globe and triggered by different mechanisms, all seem to follow a single relation, with their volume to surface area ratio following a power law of ∼1.4. This paper presents an analytical examination of the shape of landslides on the basis of limit equilibrium principles involving the exact mathematical solution of the failure mode. The obtained analytical relation between the volume and the surface area of a landslide agrees well with the function obtained from the field observations, and hence a mechanical basis is given to the previously poorly understood field observations. In addition, this paper presents a new graphical interpretation of the factor of safety associated with slope stability analysis and its relation to the probability of failure.
Synthesis and evaluation of a tri-tyrosine decorated dextran MR contrast agent for vulnerable plaque detection
Authors: Beilvert Anne , Vassy Roger , Canet-Soulas Emmanuelle , Rousseaux Olivier , Picton Luc , Letourneur Didier , Chaubet Frédéric
Published: April 2011

A tri-tyrosine grafted macromolecular MR contrast agent specifically enlightens the plaque lipid rich necrotic core in a mouse model of atherosclerosis.
Decarboxylation of aromatic carboxylic acids by gold(i)-N-heterocyclic carbene (NHC) complexes
Authors: Dupuy Stéphanie , Lazreg Faïma , Slawin Alexandra M. Z. , Cazin Catherine S. J. , Nolan Steven P.
Published: April 2011

A recently isolated gold(i) complex, [Au(IPr)(OH)], permits the transformation of carboxylic acids to the corresponding decarboxylated gold(i)-aryl complex without the use of silver co-catalyst under mild reaction conditions.
Cognitive Communicative Challenges in TBI: Assessment and Intervention in the Long Term
Authors: Cook Lori G. , DePompei Roberta , Chapman Sandra B.
Published: April 2011

Neurocognitive stall is defined as a failure or lag in achieving later emerging cognitive milestones, representing an increasing “gap” in neurocognitive, social, and educational functioning after early brain injury (Chapman, 2006). This paper provides an overview of the subject in regard to pediatric traumatic brain injury (TBI), briefly discussing both ineffective and proactive methods for detecting and monitoring later emerging deficits associated with neurocognitive stall. The paper concludes with discussion of an emerging intervention to mitigate impairments in higher-order cognitive skills and enhance learning efficiency, including suggestions for use in rehabilitation settings and within school environments.
One Center's Approach to the Assessment and Treatment of the Pediatric Minimally Conscious State
Authors: Fuith-Costa Julie , DeMarco Kathryn
Published: April 2011

Children are surviving severe brain injuries and arriving at rehabilitation centers across the country in a minimally conscious state (MCS). The MCS is defined as a condition of severely altered consciousness in which minimal but definite behavioral evidence of self or environmental awareness is demonstrated. This relatively new working definition has challenged health care providers to expand their therapeutic scope and begin working with children in a disordered state of consciousness, who previously may not have been deemed appropriate for therapy services due to lack of consciousness. Currently, within the field of speech-language pathology, a lack of evidence exists supporting the assessment and/or treatment of children in a MCS. This article seeks to provide a better understanding of the MCS in children, the characteristics consistent with the MCS, and one inpatient acute rehabilitation center's approach to the assessment and treatment of these children. Further research is needed to develop standardized assessment procedures and treatment protocols and promote a multidisciplinary approach to the management of children with the MCS.
Microfluidic devices for studying heterotypic cell-cell interactions and tissue specimen cultures under controlled microenvironments
Authors: Zervantonakis Ioannis K. , Kothapalli Chandrasekhar R. , Chung Seok , Sudo Ryo , Kamm Roger D.
Published: April 2011

Microfluidic devices allow for precise control of the cellular and noncellular microenvironment at physiologically relevant length- and time-scales. These devices have been shown to mimic the complex in vivo microenvironment better than conventional in vitro assays, and allow real-time monitoring of homotypic or heterotypic cellular interactions. Microfluidic culture platforms enable new assay designs for culturing multiple different cell populations and/or tissue specimens under controlled user-defined conditions. Applications include fundamental studies of cell population behaviors, high-throughput drug screening, and tissue engineering. In this review, we summarize recent developments in this field along with studies of heterotypic cell-cell interactions and tissue specimen culture in microfluidic devices from our own laboratory.
Magnetostriction and magnetic properties of Fe-Ga melt-spun ribbons
Authors: Saito Tetsuji , Sudo Keiichi
Published: April 2011

Fe100-xGax (x = 10–25) melt-spun ribbons, with a width of 8 mm and a thickness of 0.1 mm, were successfully produced regardless of the Ga content of the Fe-Ga alloys. The saturation magnetization of the Fe-Ga melt-spun ribbons decreased and their permeability increased with increasing Ga content. A magnetostriction of 320 ppm was achieved in the Fe87.5Ga12.5 melt-spun ribbon. Annealing of the melt-spun ribbons resulted in further increases in magnetostriction value. A large magnetostriction value of 500 ppm was achieved in the annealed Fe80Ga20 melt-spun ribbon with the A2 (bcc α-Fe) structure.
Concentration dependence of magnetic moment in Ni50Mn50−xInx/2Sbx/2 alloys with Heusler structure
Authors: Ito W. , Xu X. , Umetsu R. Y. , Kanomata T. , Ishida K. , Kainuma R.
Published: April 2011

The concentration dependence of magnetic properties in the austenite phase of Ni50Mn50−xInx/2Sbx/2 Heusler alloys was systematically investigated by magnetization measurements. The Curie temperature for Ni50Mn50−xInx/2Sbx/2 alloys is almost independent of content x. On the other hand, the concentration dependence on magnetic moment shows a concave curve similar to that of Ni50Mn50−xSnx alloys, which have the same number of valence electrons. This tendency suggests that the magnetic moment continues to increase with decreasing content x and reaches that of the metastable ferromagnetic NiMn-B2 phase.
Effect of electric field on magneto-transport properties in La2/3(Ca0.6Ba0.4)1/3MnO3/Pb(Zr0.52Ti0.48)O3 laminated composite
Authors: Chen S. Y. , Ye Q. Y. , Wang D. H. , Li S. D. , Huang Z. G. , Du Y. W.
Published: April 2011

The effects of electric field on the magnetization and Hall resistivity were investigated in a laminated composite consisting of polycrystalline perovskite La2/3(Ca0.6Ba0.4)1/3MnO3 (LCBMO) material and Pb(Zr0.52Ti0.48)O3 (PZT) ferroelectric ceramic. Upon applying an electric field (9 kV/cm) on the ferroelectric ceramic, the Hall resistivity change of the LCBMO layer is up to − 23%. The electric field-modulated Hall resistivity in LCBMO/PZT composite is attributed to the coaction of magnetization change and carrier concentration change, which result from stress-induced variation of both metal–insulator transition and ferromagnetic–paramagnetic transition.
Measurement of magnetic near field on a coplanar waveguide using a MFM tip
Authors: Endo Yasushi , Watanabe Masatoshi , Mitsuzuka Yoshio , Shimada Yutaka , Yamaguchi Masahiro
Published: April 2011

This paper proposes a method to measure the ac magnetic field distribution in close proximity to a coplanar waveguide (CPW) employing a cantilever tip fabricated for magnetic force microscopy as a sensor. Almost the entire surface of the tip is coated with a magnetically hard film (Co–Cr–Pt), which is magnetized vertically. Herein we focus on the accuracy of the tip image distribution in close proximity of the ac fields from downsized CPWs which, for example, have a signal line as fine as 5 μm and ground lines of 50 μm. The results suggest that the system has potential as a micron scale RF field detector, although a few technological problems must be solved.
Effect of weak dipolar interaction on the magnetic properties of Ni nanoparticles assembly analyzed with different protocols
Authors: Masunaga S. H. , Jardim R. F. , Rivas J.
Published: April 2011

The effect of weak dipolar interactions (DIs) between Ni nanoparticles (NPs) in samples with different Ni concentrations was investigated by performing a detailed characterization of their structural and magnetic properties. From the determination of several physical parameters of Ni NP assemblies, it was found that the ac and dc magnetic susceptibility measurements are valuable for identifying the DIs between NPs while hysteresis loops measurements showed to be very insensitive, provided that the strength of the DI field is much smaller than the maximum coercive field. Therefore, the sensitivity of the observed static and dynamical magnetic properties to the effect of weak DI depends on the measurement protocols used.
Magneto-optical garnet waveguides on semiconductor platforms: Magnetics, mechanics, and photonics
Authors: Sung Sang-Yeob , Sharma Anirudh , Block Andrew , Keuhn Katherine , Stadler Bethanie J. H.
Published: April 2011

Garnet films with thicknesses of 100–1000 nm and waveguides with widths of 700–2000 nm were grown onto Si to characterize the mechanical stresses that occurred upon crystallization (700–800 °C) by rapid thermal annealing. These magneto-optical garnet films and also photonic crystals have proposed uses in magnetic flux indicator films, integrated photonic devices, such as isolators, circulators, and polarization transformers, because their Verdet constants per unit loss are orders of magnitude better than other magneto-optical materials. However, garnet does not match Si-based materials mechanically with thermal expansion coefficients of 10.4 ppm/°C. These waveguides were optimized to have low losses in the near infrared, including the telecommunication wavelengths (1.0–2.3 dB/mm at 1.3 μm and 0.9–1.7 at 1.55 μm). The waveguide losses increased with waveguide width. Finite difference time domain simulations were used to estimate the number, effective index, and profile of modes in each guide. The polarization and localization of modes near guide surfaces effectively explain the trend in losses versus width. With Faraday rotations of 0.2 dB/μm and 1.0 dB/mm loss, this integrated garnet has great potential for a multitude of photonic devices, including isolators, circulators, and mode converters.
Correlation of microstructure, intrinsic magnetization switching properties, and recording performance in exchange-coupled composite media
Authors: Srinivasan Kumar , Roddick Eric , Mardinly John , Acharya B. Ramamurthy
Published: April 2011

The analytical model for the intrinsic coercive squareness parameter, Sint* was applied to hard–soft stacked exchange-coupled composite media, and correlations with the microstructure and switching were studied. Thickening the hard magnetic layer in the composite stack led to a decrease in Sint*, as did thickening the NiW seed layers. However, this decrease was masked by thermal effects at the normal magnetometry time-scales of measurement. Upon thickening the soft layer in the composite stack, Sint* increased sharply at first and then only slightly. In contrast, the extent of incoherent switching, estimated from the peak value of the minor loop slope, increased slowly at first, and then sharply. The changes in Sint* and switching are correlated to the microstructure, particularly, grain size effects for the NiW series and growth effects for the hard–soft composite media series. Media signal-to-noise ratio at low recording frequencies, and adjacent track interference also show correlations with Sint*.
Noise induced resonance phenomena in stochastically driven hysteretic systems
Authors: Dimian M. , Andrei P.
Published: April 2011

Noise is mainly seen as a disruptive effect and poses fundamental limits for further improvements of various technologies, such as magnetic data storage. However, noise can also play a constructive role in nonlinear systems, activating some kind of resonance response. Here, it is proved that various hysteretic systems can exhibit such noise induced amplification of the system response. The quantities used in our study to characterize this behavior are signal amplification and signal-to-noise ratio, which displays a maximum at the resonant noise strength. The resulting statistical technique that includes various algebraic, differential, and integral models of hysteresis have been implemented in freely available academic software.
Fluxmetric-magnetooptical approach to broadband energy losses in amorphous ribbons
Authors: Magni Alessandro , Fiorillo Fausto , Caprile Ambra , Ferrara Enzo , Martino Luca
Published: April 2011

The magnetization process in field annealed amorphous ribbons has been investigated from dc to 10 MHz. Loss and permeability measurements, carried out both on single strips and ring samples by means of a broadband fluxmetric setup, have been associated with observations of the domain wall dynamics by high-speed stroboscopic Kerr apparatus. Transverse anisotropy Co-based ribbons exhibit a combination of rotational and domain wall processes, the latter being observed to progressively damp with frequency and coming to a halt on approaching the megahertz range. Given the vanishing direct contribution of the domain walls to the high-frequency magnetization process, the so-called classical loss formulation, associated with the rotational magnetization processes, is expected to correspondingly hold for the energy loss W(f). Under these conditions, W(f) tends to increase linearly with f, which, in view of the expected surge of the skin effect, does not agree with the f1/2 behavior accordingly predicted by standard formulas. This points to the specific properties of the rotational process and the role played by the exchange torque in connection with incomplete flux penetration.
Monodispersed magnetite nanoparticles optimized for magnetic fluid hyperthermia: Implications in biological systems
Authors: Khandhar Amit P. , Ferguson R. Matthew , Krishnan Kannan M.
Published: April 2011

Magnetite (Fe3O4) nanoparticles (MNPs) are suitable materials for Magnetic Fluid Hyperthermia (MFH), provided their size is carefully tailored to the applied alternating magnetic field (AMF) frequency. Since aqueous synthesis routes produce polydisperse MNPs that are not tailored for any specific AMF frequency, we have developed a comprehensive protocol for synthesizing highly monodispersed MNPs in organic solvents, specifically tailored for our field conditions (f = 376 kHz, H0 = 13.4 kA/m) and subsequently transferred them to water using a biocompatible amphiphilic polymer. These MNPs (σavg. = 0.175) show truly size-dependent heating rates, indicated by a sharp peak in the specific loss power (SLP, W/g Fe3O4) for 16 nm (diameter) particles. For broader size distributions (σavg. = 0.266), we observe a 30% drop in overall SLP. Furthermore, heating measurements in biological medium [Dulbecco’s modified Eagle medium (DMEM) + 10% fetal bovine serum] show a significant drop for SLP (∼30% reduction in 16 nm MNPs). Dynamic Light Scattering (DLS) measurements show particle hydrodynamic size increases over time once dispersed in DMEM, indicating particle agglomeration. Since the effective magnetic relaxation time of MNPs is determined by fractional contribution of the Neel (independent of hydrodynamic size) and Brownian (dependent on hydrodynamic size) components, we conclude that agglomeration in biological medium modifies the Brownian contribution and thus the net heating capacity of MNPs.
Micro-structured ferromagnetic tubes for spin wave excitation
Authors: Kozhanov A. , Ouellette D. , Rodwell M. , Allen S. J. , Lee D. W. , Wang S. X.
Published: April 2011

Micron scale ferromagnetic tubes placed on the ends of ferromagnetic CoTaZr spin waveguides are explored in order to enhance the excitation of backward volume magnetostatic spin waves. The tubes produce a closed magnetic circuit about the signal line of the coplanar waveguide and are, at the same time, magnetically contiguous with the spin waveguide. This results in a ten-fold increase in spin wave amplitude. However, the tube geometry distorts the magnetic field near the spin waveguide, and relatively high biasing magnetic fields are required to establish well-defined spin waves. Only the lowest (uniform) spin wave mode is excited.
Micromagnetic study of phase-locking in spin-transfer nano-oscillators driven by currents and ac fields
Authors: d’Aquino M. , Serpico C. , Bonin R. , Bertotti G. , Mayergoyz I. D.
Published: April 2011

The magnetization dynamics of a spin-transfer nano-oscillator is studied for a system subject to the combined action of dc spin-polarized electric current and microwave circularly polarized applied field. The uniform mode theory is developed for a spin-valve with an arbitrary orientation of the polarizer. The theory enables one to predict the control parameters for the synchronization between the magnetization self-oscillation and the external microwave field. Full micromagnetic simulations are performed with the predicted control parameters, and they demonstrate the hysteretic nature of the synchronization in very good agreement with the theory.
The A1 to L1 transformation in FePt films with ternary alloying additions of Mg, V, Mn, and B
Authors: Wang B. , Barmak K. , Klemmer T. J.
Published: April 2011

The impact of ternary additions of Mg, V, Mn, and B on the A1 [face centered cubic (fcc)] to L10 phase transformation has been studied. The films were cosputter deposited from elemental targets at room temperature and annealed after deposition. The films had Mg additions in the range ∼0–2.6 at.%, V additions in the range 0.7–12.2 at.%, Mn additions in the range 2.2–16.3 at.%, and B additions in the range 1.2–12.9 at.%. For all four ternary alloy systems, annealing resulted in the formation of no other phases than the L10 phase. Ternary additions of <1.8 at.% Mg, <5.8 at.% V, <6.0 at.% Mn, and <4.8 at.% B had little or no impact on the kinetic ordering temperature (KOT). The behavior of the activation energy for the transformation mirrored that for the KOT, except for Mg additions, which showed no measurable impact for the compositions studied. The transformation enthalpies for the ternary alloys were similar to those for binary FePt films. Only four of the films (with additions of 2.6 at.% Mg, 2.2 at.% and 6.0 at.% Mn, and 4.8 at.% B) for which the Curie transition was observed had lower TC than the binary FePt films with the same Pt content.
Direct chemical synthesis of L1 FePt nanoparticles
Authors: Tzitzios Vasilis , Basina Georgia , Colak Levent , Niarchos Dimitrios , Hadjipanayis George
Published: April 2011

Ordered faced-centered tetragonal (fct) FePt nanoparticles were successfully synthesized by a chemical method using presynthesized Au nanoparticles as the “catalyst.” The reaction temperature was also studied and it seems that there is an optimum value of 360 °C where the fct structure is formed. The particles have a mean diameter of 3.5–15 nm and the x-ray diffraction patterns exhibited (001) and (110), which signified the tetragonal phase formation. Room temperature magnetic hysteresis loops show that the FePt particles have coercive fields between 0.68 and 2.8 kOe.
Study on synthesis and optical properties of Al-doped ZnO hierarchical nanostructures
Authors: Wang X. H. , Li R. B. , Fan D. H.
Published: April 2011

Highly densified Al-doped ZnO (denoted as Al-ZnO) hierarchical nanostructures were synthesized on transparent quartz substrate by chemical vapor deposition. It is found that the heating temperature plays a key role on controlling the morphologies of the Al-ZnO hierarchical nanostructures through a temperature dependent migration of Al atoms. Such uneven distribution of Al element in the hierarchical nanostructures is clearly evidenced by the x-ray photoelectron spectrum (XPS) measurements. The obtained Al-ZnO hierarchical nanostructures have transmittance of above 60% in the visible region. The photoluminescence (PL) spectra at low-temperature (20 K) were also measured.
Experimental feasibility of spin-torque oscillator with synthetic field generation layer for microwave assisted magnetic recording
Authors: Matsubara Masato , Shiimoto Masato , Nagasaka Keiichi , Sato Yo , Udo Yuta , Sugiura Kenji , Hattori Masashi , Igarashi Masukazu , Nishida Yasutaka , Hoshiya Hiroyuki , Nakamoto Kazuhiro , Tagawa Ikuya
Published: April 2011

We investigated the oscillation characteristics of a fabricated spin-torque oscillator (STO) with a synthetic field generation layer (FGL) composed of the FGL and perpendicular anisotropy magnetic layer in microwave assisted magnetic recording (MAMR). The fabricated STO was composed of a perpendicularly magnetized reference layer/interlayer/synthetic-FGL. The STO with synthetic-FGL showed very narrow peaks caused by spin-torque oscillation. We also found oscillating frequency of the fabricated STO increased as the external field increased. This implies that the FGL magnetization rotates out-of-plane. Calculations by micromagnetic simulation were qualitatively consistent with the STO measurements. The calculated magnetization configurations in the synthetic-FGL formed a single domain but the one in the single-FGL formed multiple domains. This is one reason that the synthetic-FGL is estimated to generate a larger ac-field. In sum, we experimentally confirmed the effective oscillation of fabricated STO with a synthetic-FGL even with a thick FGL and its feasibility for high areal density in MAMR.
Vortex shedding from a step-cylinder in spanwise sheared flow
Authors: Dunn Warren , Tavoularis Stavros
Published: April 2011

Vortex-shedding patterns behind a step-cylinder in uniformly shear flow for Reynolds numbers between 152 and 674 were studied using flow visualization and laser Doppler velocimetry. The results were analyzed using spectral analysis and the wavelet transform. The effect of shearing on vortex shedding was found to be significant. As in uniform flow, the step-change in diameter caused the formation of a distinct near-step vortex cell behind the large cylinder, with frequency lower than those in both neighboring cells. Shearing affected both the spanwise length of this cell and the difference between its frequency and that in the adjacent large-cylinder cell. The values of these parameters were found to depend on both the Reynolds number and the orientation of the cylinder axis relative to the shear direction.
Mesoscopic analysis of networks: Applications to exploratory analysis and data clustering
Authors: Granell Clara , Gómez Sergio , Arenas Alex
Published: April 2011

We investigate the adaptation and performance of modularity-based algorithms, designed in the scope of complex networks, to analyze the mesoscopic structure of correlation matrices. Using a multiresolution analysis, we are able to describe the structure of the data in terms of clusters at different topological levels. We demonstrate the applicability of our findings in two different scenarios: to analyze the neural connectivity of the nematode Caenorhabditis elegans and to automatically classify a typical benchmark of unsupervised clustering, the Iris dataset, with considerable success.