bluuebunny/crossref_metadata_2025 huggingface dataset:
Forgotten Futures: Indian Muslims in the Trans-Islamic Turn to Japan
Authors: Green Nile
Published: June 2013

This essay casts light on the alternative but unrealized futures imagined through the Indian Muslim encounter with Japan in the inter-war period. Echoing other attempts to destabilize the empire-to-nation teleology of Indo-Pakistani independence, the essay uncovers a set of aspirations, actors, and spaces of comparison by which Indian Muslims sought an independent future for Muslim-ruled princely states such as Hyderabad. Through comparison with similar patterns in other Asian princely states, a case study of Urdu writings on Japan shows how East Asia became a place to imagine for Hyderabad a future that never came to fruition. By locating India in a trans-Islamic pattern of engaging Japan, the essay shows how, between the Russo-Japanese War and the Second World War, Japan provided newly globalized intellectuals with a template for empowering Muslim-ruled polities that either never came into existence or were subsumed by Asia's postcolonial nations.
The use of soy protein polymers as a release device for nematophagous fungi in the control of parasitic nematodes in ruminants
Authors: Sagüés M.F. , Purslow P. , Fernández A.S. , Iglesias L.E. , Fusé L.A. , Saumell C.A.
Published: June 2013

This trial was conducted to evaluate the predatory activity of Duddingtonia flagrans incorporated into soy protein-based polymers as a controlled-release device (CRD). The rate of fungal release from the polymers and time of residence of the CRD in the rumen of a cannulated sheep was also determined. After administration to the sheep, the CRD was extracted at weekly intervals over a month for observation of its physical structure and faeces were collected to observe the subsequent predatory activity of the fungus in Petri dishes with water-agar 2% and Panagrellus spp. as bait. The CRD slowly degraded in the rumen over 4 weeks and liberated D. flagrans into the faeces. The formulation of the soy protein-based polymers did not affect the predatory activity of the fungus. The study demonstrates that biodegradable soy protein polymers could potentially improve the use of nematophagous fungi for controlling nematode parasites of ruminants.
Habitat-specific seed dormancy-release mechanisms in four legume species
Authors: van Klinken Rieks D. , Goulier Jean-Baptiste
Published: June 2013

Physical seed dormancy is a common attribute among plants, and a wide range of dormancy-release mechanisms have been described, but their ecological significance is rarely tested through comparative study. This study tests whether dormancy-release responses to wet heat in four legume species with physical dormancy are correlated with habitat: two wetland species (Mimosa pigraandParkinsonia aculeata, both dispersed primarily by water) and two terrestrial species (Acacia niloticaandProsopis pallida, both dispersed primarily through vertebrate herbivores). Dormancy release was compared at three moisture levels (80% relative humidity, saturated and submerged) at constant (20–45°C) and diurnally fluctuating (20/40°C) temperatures for 14 d. Seed viability was tested by germinating at 25°C. The functional relationship between temperature and dormancy release after 14 d differed between species: submerged seeds of the two wetland species showed a quadratic response, with low rates of imbibition below 20–25°C and complete imbibition at around 40°C;P. pallidaseeds showed a linear positive relationship, whereas there was no temperature response forA. niloticaseeds below 45°C. Surprisingly, dormancy release after 14 d was relatively insensitive to moisture levels, although rate of dormancy release was generally slower under drier conditions. Dormancy release was not influenced by fluctuating temperatures. Seed viability was largely unaffected by temperature or moisture regime, although it did differ with species and was lower for non-dormant seeds. Our results suggest that a functional dormancy-release response to wet heat provides important fitness benefits for wetland species, but not for species dispersed through vertebrate herbivores, for which it may be maladaptive.
Lipschitz Functions on Expanders are Typically Flat
Authors: PELED RON , SAMOTIJ WOJCIECH , YEHUDAYOFF AMIR
Published: June 2013

This work studies the typical behaviour of random integer-valued Lipschitz functions on expander graphs with sufficiently good expansion. We consider two families of functions: M-Lipschitz functions (functions which change by at most M along edges) and integer-homomorphisms (functions which change by exactly 1 along edges). We prove that such functions typically exhibit very small fluctuations. For instance, we show that a uniformly chosen M-Lipschitz function takes only M+1 values on most of the graph, with a double exponential decay for the probability of taking other values.
Review Article Socio-economic determinants of micronutrient intake and status in Europe: a systematic review
Authors: Novaković Romana , Cavelaars Adriënne , Geelen Anouk , Nikolić Marina , Altaba Iris Iglesia , Viñas Blanca Roman , Ngo Joy , Golsorkhi Mana , Medina Marisol Warthon , Brzozowska Anna , Szczecinska Anna , de Cock Diederik , Vansant Greet , Renkema Marianne , Majem Lluís Serra , Moreno Luis Aznar , Glibetić Maria , Gurinović Mirjana , van't Veer Pieter , de Groot Lisette CPGM
Published: June 2013

Objective

To provide the evidence base for targeted nutrition policies to reduce the risk of micronutrient/diet-related diseases among disadvantaged populations in Europe, by focusing on: folate, vitamin B12, Fe, Zn and iodine for intake and status; and vitamin C, vitamin D, Ca, Se and Cu for intake.

Design

MEDLINE and Embase databases were searched to collect original studies that: (i) were published from 1990 to 2011; (ii) involved >100 subjects; (iii) had assessed dietary intake at the individual level; and/or (iv) included best practice biomarkers reflecting micronutrient status. We estimated relative differences in mean micronutrient intake and/or status between the lowest and highest socio-economic groups to: (i) evaluate variation in intake and status between socio-economic groups; and (ii) report on data availability.

Setting

Europe.

Subjects

Children, adults and elderly.

Results

Data from eighteen publications originating primarily from Western Europe showed that there is a positive association between indicators of socio-economic status and micronutrient intake and/or status. The largest differences were observed for intake of vitamin C in eleven out of twelve studies (5–47 %) and for vitamin D in total of four studies (4–31 %).

Conclusions

The positive association observed between micronutrient intake and socio-economic status should complement existing evidence on socio-economic inequalities in diet-related diseases among disadvantaged populations in Europe. These findings could provide clues for further research and have implications for public health policy aimed at improving the intake of micronutrients and diet-related diseases.
NONLINEAR WAVE EQUATIONS AND REACTION–DIFFUSION EQUATIONS WITH SEVERAL NONLINEAR SOURCE TERMS OF DIFFERENT SIGNS AT HIGH ENERGY LEVEL
Authors: XU RUNZHANG , YANG YANBING , CHEN SHAOHUA , SU JIA , SHEN JIHONG , HUANG SHAOBIN
Published: June 2013

This paper is concerned with the initial boundary value problem of a class of nonlinear wave equations and reaction–diffusion equations with several nonlinear source terms of different signs. For the initial boundary value problem of the nonlinear wave equations, we derive a blow up result for certain initial data with arbitrary positive initial energy. For the initial boundary value problem of the nonlinear reaction–diffusion equations, we discuss some probabilities of the existence and nonexistence of global solutions and give some sufficient conditions for the global and nonglobal existence of solutions at high initial energy level by employing the comparison principle and variational methods.
The experiences, coping mechanisms, and impact of death and dying on palliative medicine specialists
Authors: Zambrano Sofia C. , Chur-Hansen Anna , Crawford Gregory B.
Published: June 2013

Objectives:

Research on the experiences, coping mechanisms, and impact of death and dying on the lives of palliative medicine specialists is limited. Most research focuses on the multidisciplinary team or on nurses who work with the dying. Fewer studies consider medical professionals trained in palliative medicine. This study aimed to explore the experiences, coping mechanisms, and impact of death and dying on palliative medicine specialists when dealing with their patients at the end of life.

Methods:

A qualitative research approach guided the study, one-on-one interview data were analyzed thematically. A purposeful sampling technique was employed for participant recruitment. Seven palliative medicine specialists practicing in one city participated in open-ended, in-depth interviews.

Results:

The analysis of participants' accounts identified three distinct themes. These wereBeing with the dying,Being affected by death,and dyingandAdjusting to the impact of death and dying.

Significance of results:

This study further contributes to the understanding of the impact of death and dying on professionals who care for dying patients and their families. Despite the stressors and the potential for burnout and compassion fatigue, these participants employed strategies that enhanced meaning-making and emphasized the rewards of their work. However, the consequences of work stressors cannot be underestimated in the practice of palliative care.
Microsatellite markers for common lilac (Syringa vulgaris L.)
Authors: Juntheikki-Palovaara Inka , Antonius Kristiina , Lindén Leena , Korpelainen Helena
Published: June 2013

Common lilac is a popular landscape plant with nearly 2000 cultivars. In the present study, nine novel polymorphic microsatellite markers were developed for common lilac using genome screening with inter-simple sequence repeat primers. Each of the nine markers revealed two to five alleles. The markers were used for genotyping of 75 common lilac shrubs, including 17 accessions that represented named cultivars. A dendrogram, based on the allele profiles of the shrubs, was generally in agreement with the grouping made on the basis of morphological traits, as well as with the pedigree information available. The novel markers appear valuable for differentiation between common lilac cultivars.
The type III TGFβ receptor regulates filopodia formation via a Cdc42-mediated IRSp53–N-WASP interaction in epithelial cells
Authors: Oh Sun Young , Knelson Erik H. , Blobe Gerard C. , Mythreye Karthikeyan
Published: June 2013

Cell adhesion and migration are tightly controlled by regulated changes in the actin cytoskeleton. Previously we reported that the TGFβ (transforming growth factor β) superfamily co-receptor, TβRIII (type III TGFβ receptor; also known as betaglycan), regulates cell adhesion, migration and invasion, and suppresses cancer progression, in part, through activation of the small GTPase Cdc42 (cell division cycle 42), and Cdc42-dependent alterations to the actin cytoskeleton. In the present study we demonstrate that TβRIII specifically promotes filopodial formation and extension in MCF10A and HMEC (human mammary epithelial cell) mammary epithelial cells. Mechanistically, cell-surface TβRIII and Cdc42 co-localize to filopodial structures and co-complex in a β-arrestin2-dependent, and a TβRI/TβRII-independent manner. The β-arrestin2-mediated interaction between TβRIII and Cdc42 increases complex formation between the Cdc42 effectors IRSp53 with N-WASP (neuronal Wiskott–Aldrich syndrome protein) to increase filopodial formation. We demonstrate a function link between filopodial structures and epithelial cell adhesion as regulated by the TβRIII–Cdc42 interaction. The present studies identify TβRIII as a novel regulator of IRSp53/N-WASP via Cdc42 to regulate filopodial formation and cell adhesion.
Automation of residential load in power distribution systems with focus on demand response
Authors: Deese Anthony S. , Carrigan Brian , Stein Elliot , Klein Elie
Published: June 2013

This paper examines the automation of residential loads for participation in demand response (DR) within electric power distribution networks. The authors present a simple yet effective automation solution. It is custom hardware designed to observe the environment of as well as power utilisation within a residence, analyse the optimality of its load configuration, and physically activate or deactivate devices to achieve user‐defined objectives. Their prototype is constructed with commercially available technologies such as the digital microconrtoller, radio frequency wireless transceiver and solid‐state relay. It provides the utility customer an opportunity to reap the financial benefits associated with DR by allowing an independent system operator, or similar body, to exercise limited control over home appliances, heating and cooling units, as well as personal electronics. In this work, the authors emphasise the importance of solution effectiveness, as well as simplicity. The study focuses on research related to load automation and DR, not development of a commercial product.
New methodology for grouping electric power consuming units to meet continuity indicators targets established by the Brazilian Regulatory Agency
Authors: Conde Guilherme Augusto Barros , dos Santos Fábio Correa , de Santana Adamo Lima , Silva Rogério Diogne , Francês Carlos Renato Lisboa , Tostes Maria Emília de Lima
Published: June 2013

The Brazilian electrical utility companies must meet continuity indicators for energy supply, which are represented by the indices of average interruption duration and frequency, according to targets established by the Brazilian Regulatory Agency for Electrical Energy (ANEEL). In a nationwide base, ANEEL has defined 30 clusters, each one having specific targets for Customer Average Duration Interruption Index and Customer Average Frequency Interruption Index; still, very frequently the utility distribution companies are financially penalised for not meeting these indicator targets. This study proposes a decision support system based on machine learning techniques so that the utility distribution companies can emulate the characteristics and procedures used by the ANEEL, and help in obtaining more adequate customer groups to evaluate the duration and frequency indicators. The proposed system was applied in a case study of a distribution utility whose supply area is located in the Brazilian Amazonia. The methodology proved to be adequate for seeking better customer grouping configurations that could result in a decrease in goal violations as well as providing more consistent goals, considering the specific characteristics of each distribution utility. Although this methodology was applied to a Brazilian scenario it also can be applied to other distribution utilities worldwide.
AC–DC optimal reactive power flow model via predictor–corrector primal‐dual interior‐point method
Authors: Nie Yonghui , Du Zhengchun , Li Jiang
Published: June 2013

This study presents a quadratic optimal reactive power flow (ORPF) models for ac‐dc hybrid power system. In the ac system, the load tap changing transformer is represented by an ideal transformer and its series impedance with an artificial node located between them. The ideal transformer is further replaced by the current injections at the two terminal nodes. The artificial node voltage and the current injections are used to express the relationship between the quantities at both sides. For the dc system, some variables are introduced to formulate the dc equations. Finally, utilising their couplings, the ac and dc equations expressed in different coordinates can be integrated into a unified quadratic ac‐dc ORPF model, which is simply expressed in the block form. The predictor‐corrector primal‐dual interior‐point method is used to solve the optimisation problem. The quadratic model results in the constant Hessians that all have elements of 1 or −1, and mostly being zero and multiplication is not required to form the full Hessian, thereby accelerating the entire optimal process significantly. Extensive numerical simulations have shown the validity and superior performance of the proposed model than the conventional one.
Directional relaying for double circuit line with series compensation
Authors: Biswal Monalisa , Pati Bibhuti Bhusan , Pradhan Ashok Kumar
Published: June 2013

In this paper, a directional relaying algorithm for the protection of double circuit line with series capacitor is presented. The method uses four classifiers based on positive and negative sequence components which are combined with a voting technique to derive the direction of fault. The technique is evaluated using data simulated with electromagnetic transients including DC/power system computer added design (EMTDC/PSCAD) for a series compensated double circuit line. Results for voltage inversion, current inversion, high resistance far end fault, single pole tripping and cross country fault are presented. The proposed technique is found to be accurate.
Low‐cost intelligent antenna with low profile and broad bandwidth
Authors: Liu Haitao , Gao Steven , Loh Tian Hong , Qin Fei
Published: June 2013

In this study, a low‐cost intelligent antenna, which has a low profile, high gain and broad bandwidth, is presented. The proposed antenna is an extension of the conventional electronically steerable parasitic array radiator antenna. It consists of one short monopole and 12‐folded monopoles. The short monopole is placed in the centre and serves as the driven element and the 12‐folded monopoles serve as parasitic elements. The coupling between the driven and parasitic elements provides capacitive loading to the driven element, leading to a low‐profile antenna. The use of 12 PIN diodes enables beamforming to be performed using a transistor–transistor logic supply. The front‐to‐back‐ratio (FBR) is improved by introducing a reconfigurable choke ring surrounding the antenna. To validate the concept, a prototype at S band is developed. Both measured and simulated results are presented. The antenna has a height of only 24 mm (0.16 λ at 2.0 GHz) and a broadband bandwidth from 2.0 to 2.5 GHz. Finally, the antenna is employed in a wireless communication system in a multi‐path environment and large noise environment. It is shown that the antenna can boost the throughput of a wireless system significantly in both environments.
Frequency reconfigurable planar inverted‐F antenna using switchable radiator and capacitive load
Authors: Lim Jong‐Hyuk , Song Chang‐Wook , Jin Zhe‐Jun , Yun Tae‐Yeoul
Published: June 2013

A frequency reconfigurable planar inverted‐F antenna (PIFA) using real PIN‐diodes is presented for mobile worldwide interoperability for microwave access (m‐WiMAX) applications. This antenna not only alters the frequency band of the m‐WiMAX using PIN‐diode switching, but it also has a small profile using capacitive load within an FR4 dielectric constant substrate. The PIFA consists of the following: a main radiator, an additional radiator, a band‐switchable capacitive load, two PIN‐diodes and control circuits. One diode is placed between the main and additional radiator on the top side, and the other is vertically attached between the capacitive load and ground. Depending upon whether the diodes are on or off, the antenna operates over 2.3–2.4, 2.5–2.7 and 3.4–3.6 GHz for worldwide m‐WiMAX bands. To investigate the effect of load capacitance, a parametric analysis is performed by sweeping the length and width of the capacitive load. All simulated and measured results for the proposed antenna are presented, and they show excellent agreement.
Ka‐band waveguide rotary joint
Authors: Yevdokymov Anatoliy , Kryzhanovskiy Volodymyr , Pazynin Vadim , Sirenko Kostyantyn
Published: June 2013

The authors present a design of a waveguide rotary joint operating in Ka‐band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.
Tunable dual‐mode microstrip patch resonators and filters
Authors: Tang Hui , Chen Jian‐Xin , Zhou Li‐Heng , Bao Zhi‐Hua
Published: June 2013

In this study, tunable dual‐mode microstrip patch resonators are presented and utilised to design microstrip bandpass filters (BPFs). The novelty of the designs lies in that the performance of frequency agility can be realised by using either the signal line or the return path (the ground) of microwave transmission line. For the proposed resonators, the resonant frequencies of two coupled degenerate modes can be tuned using a square‐loop slot with loaded tunable capacitors on the ground plane or on the patch. The locations of the capacitors are determined according to the electric field distributions of the two orthogonal modes. The variations of the modes in spectrum are studied. Finally, two types of demonstration compact tunable BPFs are designed and fabricated, and the simulated and measured results show good agreement.
Full duplex reflection amplifier tag
Authors: Chan Pak , Fusco Vincent
Published: June 2013

The authors describe a reflection amplifier adapted to have both a reflection and a transmission port. The amplifier uses a single silicon bipolar transistor and demonstrates a reflection gain of 13 dB, transmission gain of 10 dB and 3.4 dB noise figure at 5.25 GHz. The added feature of transmission gain in the reflection amplifier permits practical implementation of full duplex microwave radiofrequency indentification (RFID) tag operation. By using a simple subcarrier modulation scheme full duplex RFID operation utilising this amplifier is demonstrated. These results indicate that for 27 dBm (0.5 W) effective isotropic radiated power (EIRP) transmit power it should be possible to obtain approximately 8 m downlink range and 25 m uplink range.
Position‐only side lobe reduction of a uniformly excited elliptical antenna array using evolutionary algorithms
Authors: Sharaqa Ashraf , Dib Nihad
Published: June 2013

This study deals with the design of elliptical antenna arrays for specific radiation property using three different evolutionary algorithms; namely, self‐adaptive differential evolution method, biogeography based optimisation method and firefly algorithm. These methods are used to determine an optimum set of positions for uniformly excited elliptical antenna array (EAA) that provides a radiation pattern with optimum side lobe level reduction with the constraint of a fixed major lobe beamwidth. Three examples are investigated; 8, 12 and 20 elements EAAs using these evolutionary algorithms. The comparison shows that the design of non‐uniform EAAs using evolutionary algorithms presents a good side lobe reduction in the radiation pattern for the optimised design. Furthermore, the BBO method shows somewhat better performance compared with the other two methods.
Technique for inversion of an inhomogeneous bianisotropic slab through an optimisation approach
Authors: Farahbakhsh Ali , Zarifi Davoud , Abdolali Ali , Soleimani Mohammad
Published: June 2013

An electromagnetic inversion method is presented to reconstruct the constitutive parameters of an inhomogeneous bianisotropic slab. The measured co‐ and cross‐reflection and transmission coefficients are used to extract the electromagnetic parameters profiles of the inhomogeneous bianisotropic media from the proposed method, using truncated Fourier series expansion and Gravitational Search Algorithm (GSA). GSA is used to improve the speed and accuracy of the optimisation process because of the complexity of inhomogeneous bianisotropic media, highly non‐linearity of optimisation problem, and extremely large search space. Finally, the accuracy and robustness of the proposed reconstruction method are validated using some typical examples.
Compact multiple input and multiple output/diversity antenna for portable and mobile ultra‐wideband applications
Authors: See Chan Hwang , Hraga Hmeda Ibrahim , Noras Jim M. , Abd‐Alhameed Raed A. , McEwan Neil J.
Published: June 2013

This study presents a miniaturised multiple input and multiple output /diversity antenna which is suitable for high data‐rate communication systems such as mobile ultra‐wideband (UWB). This antenna assembly comprises two identical planar inverted‐F antennas, a T‐shaped structure connecting them and a finite ground plane. The T‐shaped structure improves the impedance matching and suppresses the mutual coupling between the antenna elements over a wider bandwidth than previously reported. The compact envelope dimension of this antenna is 50 × 90 × 7.5 mm3. Theoretical and experimental S‐parameters are illustrated for this antenna that fully cover the UWB operating frequency band of 3.1–10.6 GHz, with a reflection coefficient and mutual coupling better than −10 and −20 dB, respectively. Acceptable agreement is obtained between computed and measured radiation patterns, gains, envelope correlation coefficient and channel capacity loss. The proposed antenna is an attractive candidate to provide pattern diversity and enhance channel capacity in a rich scattering environment.
Phase in non‐reciprocal gyromagnetic waveguides using multiple ferrite tiles
Authors: Helszajn Joseph
Published: June 2013

The non‐reciprocal phase shifter in the design of the waveguide differential phase‐shift circulator consists of two or four suitably magnetised ferrite tiles on the top and bottom walls of the waveguide. It may be adjusted in terms of a reciprocal condition and a non‐reciprocal one. The first condition essentially fixes the geometry of a typical phase‐shift section except for the thickness of each ferrite tile; the second determines the connection between the split‐phase constants and the thickness of the tiles for parametric values of gyrotropy. The purpose here is to satisfy the first requirement of the two‐tile geometry using a calculation and to meet the second one by having recourse to measurements. It includes some preliminary experimental data on new four‐ and eight‐stacked ferrite tile structures. It is likely to prove of value in the design of large continuous wave power devices.
Compact split‐ring resonator‐loaded multiple‐input–multiple‐output antenna with electrically small elements and reduced mutual coupling
Authors: Ntaikos Dimitrios K. , Yioultsis Traianos V.
Published: June 2013

The authors present a compact four‐element multiple‐input–multiple‐output antenna with the potential to operate in WiMAX frequency bands, with its elements being not only closely spaced but also electrically small. Split‐ring resonators or metal stipes are utilised to achieve both goals, that is element miniaturisation and reduction of mutual coupling. The design process is systematic, as it deals with both issues quite separately. Very low values of the envelope correlation coefficient and overall good performance are obtained, without compromising planarity and simplicity.
Elektronischer Mutter(Eltern)-Kind Pass – Möglichkeiten, Zielsetzungen und internationale Erfahrungen
Authors: Piso B. , Mathis-Edenhofer S. , Schramm F. , Wild C.
Published: June 2013

Vor dem Hintergrund einer Neugestaltung des Eltern-Kind-Vorsorgeprogramms in Österreich, welche auch eine elektronische statt papierbasierte Umsetzung beinhalten könnte, soll ein Überblick internationaler Pilotierungen elektronischer Eltern-Kind-Vorsorge Initiativen (eEKVI) gegeben, und für die Umsetzung relevanten Grenzen, Möglichkeiten und Zielsetzungen dieser Projekte aufgezeigt werden.

Datenbankrecherche sowie Handsuche nach internationalen (Pilot-) Projekten.

Von 30 ausgewählten eEKVI können 9 als elektronische Eltern- bzw. Kinder-Gesundheitsakten angesehen werden, welche entweder im Kontext einer umfassenden elektronischen Gesundheitsakte, als elektronische Umsetzung eines papierbasierten Dokuments oder als an eine Einrichtung gebundene IT-Lösung realisiert wurden. eEKVI sind bislang international noch kaum flächendeckend implementiert, einige wenige bedienen neben klassischen Kern-Zielen (Abwicklung und Administration der Versorgung usw.) auch planerische Zielsetzungen und ermöglichen dadurch ein systemisches Lernen aufgrund von Feedback und Evaluationszyklen.

Basierend auf Erfahrungen internationaler eEKVI sollten Kernaspekte einer erfolgreichen Planung und Umsetzung, wie beispielsweise die Definition von erwarteten Nutzen-Zielen und deren Monitoring oder die Bildung eines für Planung und Konzeption verantwortlichen Teams unter früher Einbeziehung von Endnutzern und Akteuren, berücksichtigt werden, um vermeidbare Fehler zu minimieren. Eine konsequente Technikfolgenabschätzung – auch von IT-basierten Interventionen im Gesundheitswesen – ist jedenfalls zu fordern, um ein reflektiertes Vorgehen zu ermöglichen.
Temporal evolution of bubble tip velocity in classical Rayleigh-Taylor instability at arbitrary Atwood numbers
Authors: Liu W. H. , Wang L. F. , Ye W. H. , He X. T.
Published: June 2013

In this research, the temporal evolution of the bubble tip velocity in Rayleigh-Taylor instability (RTI) at arbitrary Atwood numbers and different initial perturbation velocities with a discontinuous profile in irrotational, incompressible, and inviscid fluids (i.e., classical RTI) is investigated. Potential models from Layzer [Astrophys. J. 122, 1 (1955)] and perturbation velocity potentials from Goncharov [Phys. Rev. Lett. 88, 134502 (2002)] are introduced. It is found that the temporal evolution of bubble tip velocity [u(t)] depends essentially on the initial perturbation velocity [u(0)]. First, when the u(0)<C(1)uasp, the bubble tip velocity increases smoothly up to the asymptotic velocity (uasp) or terminal velocity. Second, when C(1)uasp≤u(0)<C(2)uasp, the bubble tip velocity increases quickly, reaching a maximum velocity and then drops slowly to the uasp. Third, when C(2)uasp≤u(0)<C(3)uasp, the bubble tip velocity decays rapidly to a minimum velocity and then increases gradually toward the uasp. Finally, when u(0)≥C(3)uasp, the bubble tip velocity decays monotonically to the uasp. Here, the critical coefficients C(1),C(2), and C(3), which depend sensitively on the Atwood number (A) and the initial perturbation amplitude of the bubble tip [h(0)], are determined by a numerical approach. The model proposed here agrees with hydrodynamic simulations. Thus, it should be included in applications where the bubble tip velocity plays an important role, such as the design of the ignition target of inertial confinement fusion where the Richtmyer-Meshkov instability (RMI) can create the seed of RTI with u(0)∼uasp, and stellar formation and evolution in astrophysics where the deflagration wave front propagating outwardly from the star is subject to the combined RMI and RTI.
Swirling, turbulent vortex rings formed from a chain reaction of reconnection events
Authors: Kerr Robert M.
Published: June 2013

Long, straight, anti-parallel vortex tubes, with balanced profiles and a local perturbation, are simulated using the Navier-Stokes equations and evolve into a chain of spiral vortex rings with the characteristics of three-dimensional turbulence. This includes evidence of a cascade of energy to high wavenumbers, the formation of a k−5/3 inertial subrange and a new hierarchy of rescaled vorticity moments where, against expectations, the lower-order moments bound the higher-order moments. This order holds for all times even as the individual moments fluctuate significantly and could explain the observation that ratios converge faster than the individual moments in very high Reynolds number forced turbulence simulations. The transformation of the original pair of vortices into turbulent swirling vortex rings is outlined by describing first the twists and turns of the first two reconnection steps in detail, next how these create the first set of vortex rings, and finally the formation of the additional reconnections and stretched, swirling rings that lead to turbulence. The k−5/3 spectrum is interpreted in terms of a model of stretched, spiral vortices similar to those seen in these simulations.
Phonon mode of TiO2 coupled with the electron transfer from N3 dye
Authors: Nomoto Tomonori , Fujio Keita , Sasahara Akira , Okajima Hajime , Koide Naoki , Katayama Hiroyuki , Onishi Hiroshi
Published: June 2013

Low frequency vibrational spectra of submonolayer N3 dye (Ru(4,4′-dicarboxy-2,2′-bipyridine)2(NCS)2) adsorbed on TiO2 (110) were reported by using fourth-order coherent Raman spectroscopy, which is interface-sensitive vibrational spectroscopy. Most of the peaks observed in the experiment were at the same frequency as that of Raman and infrared spectra of the dye and TiO2. Two interfacial modes at 640 and 100 cm−1 and one resonantly enhanced phonon at 146 cm−1 appeared in addition to the pure TiO2 and N3 spectra. Adsorption of N3 dye on TiO2 contributed to the enhancement of 100 and 146 cm−1 mode. The results not only reported interfacial low-frequency vibrations of TiO2 (110) with N3 dye adsorption but also suggested the coupling between the surface vibrations of TiO2 and charge transfer between N3 dye and TiO2 on the surface.
Dynamical phase transitions in supercooled liquids: Interpreting measurements of dynamical activity
Authors: Fullerton Christopher J. , Jack Robert L.
Published: June 2013

We study dynamical phase transitions in a model supercooled liquid. These transitions occur in ensembles of trajectories that are biased towards low (or high) dynamical activity. We compare two different measures of activity that were introduced in recent papers and we find that they are anti-correlated with each other. To interpret this result, we show that the two measures couple to motion on different length and time scales. We find that “inactive” states with very slow structural relaxation nevertheless have increased molecular motion on very short scales. We discuss these results in terms of the potential energy landscape of the system and in terms of the liquid structure in active/inactive states.
Solute effect on oxygen diffusion in α-titanium
Authors: Wu Henry H. , Trinkle Dallas R.
Published: June 2013

We calculate first-principles interaction energies between substitutional solutes and oxygen interstitials in α-titanium and predict the effect of solutes on oxygen diffusion from those interactions. Interaction between 45 solutes across the periodic table and three oxygen interstitial sites are calculated with density-functional theory. The interaction energies show distinct trends across the periodic table corresponding to both atomic radii and the period. Changes in diffusion barrier due to solutes are modeled with the kinetically resolved activation barrier approximation. Solute effects at infinite dilution are numerically calculated and show both accelerated and reduced oxygen diffusivity.
Electronic transport in (La,Sr)MnO3-ferroelectric-(La,Sr)MnO3 epitaxial structures
Authors: Boni A. G. , Pintilie I. , Pintilie L. , Preziosi D. , Deniz H. , Alexe M.
Published: June 2013

The leakage current in all oxide epitaxial (La,Sr)MnO3-ferroelectric-(La,Sr)MnO3 structures, where the ferroelectric layer is either BaTiO3 or Pb(Zr0.2Ti0.8)O3, was analyzed on a broad range of temperatures and for different thicknesses of the ferroelectric layer. It was found that, although the structures are nominally symmetric, the current-voltage (I–V) characteristics are asymmetric. The leakage current depends strongly on the thicknesses of the ferroelectric layer, on temperature and on the polarity of the applied voltage. Simple conduction mechanisms such as space charge limited currents or thermionic emission cannot explain in the same time the voltage, temperature, and thickness dependence of the experimentally measured leakage currents. A combination between interface limited charge injection and bulk controlled drift-diffusion (through hopping in the case of BTO and through band mobility in the case of PZT) is qualitatively explaining the experimental I–V characteristics.
The influence of translational and vibrational energy on the reaction of Cl with CH3D
Authors: Berke Andrew E. , Volpa Ethan H. , Annesley Christopher J. , Crim F. Fleming
Published: June 2013

The reaction of Cl atoms with CH3D proceeds either by abstraction of hydrogen to produce HCl + CH2D or by abstraction of deuterium to produce DCl + CH3. Using Cl atoms with different amounts of translational energy, produced by photolysis of Cl2 with 309, 355, or 416 nm light, reveals the influence of translational energy on the relative reaction probability for the two channels. These measurements give an estimate of the energy barrier for the reaction for comparison to theory and indicate that tunneling is the dominant reaction mechanism at low collision energies. Adding two quanta of C–H stretching vibration causes the reaction to proceed readily at all collision energies. Detecting the vibrational state of the CH2D product shows that vibrational energy initially in the surviving C–H bond appears as vibrational excitation of the product, an example of spectator behavior in the reaction. The reaction produces both stretch and stretch-bend excited products except at the lowest collision energy. A subtle variation in the reaction probability of the lowest energy rotational states with translational energy may reflect the presence of a van der Waals well in the entrance channel.
Ultra-fast bright field and fluorescence imaging of the dynamics of micrometer-sized objects
Authors: Chen Xucai , Wang Jianjun , Versluis Michel , de Jong Nico , Villanueva Flordeliza S.
Published: June 2013

High speed imaging has application in a wide area of industry and scientific research. In medical research, high speed imaging has the potential to reveal insight into mechanisms of action of various therapeutic interventions. Examples include ultrasound assisted thrombolysis, drug delivery, and gene therapy. Visual observation of the ultrasound, microbubble, and biological cell interaction may help the understanding of the dynamic behavior of microbubbles and may eventually lead to better design of such delivery systems. We present the development of a high speed bright field and fluorescence imaging system that incorporates external mechanical waves such as ultrasound. Through collaborative design and contract manufacturing, a high speed imaging system has been successfully developed at the University of Pittsburgh Medical Center. We named the system “UPMC Cam,” to refer to the integrated imaging system that includes the multi-frame camera and its unique software control, the customized modular microscope, the customized laser delivery system, its auxiliary ultrasound generator, and the combined ultrasound and optical imaging chamber for in vitro and in vivo observations. This system is capable of imaging microscopic bright field and fluorescence movies at 25 × 106 frames per second for 128 frames, with a frame size of 920 × 616 pixels. Example images of microbubble under ultrasound are shown to demonstrate the potential application of the system.
Coulomb potential effects on spectra of graphene magnetic quantum dots
Authors: Liu Chuan , Zhu Jia-Lin , Yang Ning
Published: June 2013

The low-lying spectra of hydrogenic impurities in magnetic quantum dots of graphene are calculated numerically from the Dirac-Weyl equation. The positive and negative energy states are attracted and repelled, respectively, by the impurities. The zero-energy level is nondegenerate and its corresponding states split by the Coulomb potential into hole-like states. Modulation effects of the Coulomb potential on the spectra are explored by varying magnetic field and dot size. These behaviors can be confirmed by the corresponding electron probability densities and binding energies, which can be tested in future experiments.
Direct hysteresis measurements on ferroelectret films by means of a modified Sawyer–Tower circuit
Authors: Qiu Xunlin , Holländer Lars , Wirges Werner , Gerhard Reimund , Cury Basso Heitor
Published: June 2013

Ferro- and piezo-electrets are non-polar polymer foams or film systems with internally charged cavities. Since their invention more than two decades ago, ferroelectrets have become a welcome addition to the range of piezo-, pyro-, and ferro-electric materials available for device applications. A polarization-versus-electric-field hysteresis is an essential feature of a ferroelectric material and may also be used for determining some of its main properties. Here, a modified Sawyer-Tower circuit and a combination of unipolar and bipolar voltage waveforms are employed to record hysteresis curves on cellular-foam polypropylene ferroelectret films and on tubular-channel fluoroethylenepropylene copolymer ferroelectret film systems. Internal dielectric barrier discharges (DBDs) are required for depositing the internal charges in ferroelectrets. The true amount of charge transferred during the internal DBDs is obtained from voltage measurements on a standard capacitor connected in series with the sample, but with a much larger capacitance than the sample. Another standard capacitor with a much smaller capacitance—which is, however, still considerably larger than the sample capacitance—is also connected in series as a high-voltage divider protecting the electrometer against destructive breakdown. It is shown how the DBDs inside the polymer cavities lead to phenomenological hysteresis curves that cannot be distinguished from the hysteresis loops found on other ferroic materials. The physical mechanisms behind the hysteresis behavior are described and discussed.
Analysis of the trajectory of a sphere moving through a geometric constriction
Authors: Risbud Sumedh R. , Luo Mingxiang , Fréchette Joëlle , Drazer German
Published: June 2013

We present a numerical study of the effect that fluid and particle inertia have on the motion of suspended spherical particles through a geometric constriction to understand analogous microfluidic settings, such as pinched flow fractionation devices. The particles are driven by a constant force in a quiescent fluid, and the constriction (the pinching gap) corresponds to the space between a plane wall and a second, fixed sphere of the same size (the obstacle). The results show that, due to inertia and/or the presence of a geometric constriction, the particles attain smaller separations to the obstacle. We then relate the minimum surface-to-surface separation to the effect that short-range, repulsive non-hydrodynamic interactions (such as solid-solid contact due to surface roughness, electrostatic double layer repulsion, etc.) would have on the particle trajectories. In particular, using a simple hard-core repulsive potential model for such interactions, we infer that the particles would experience larger lateral displacements moving through the pinching gap as inertia increases and/or the aperture of the constriction decreases. Thus, separation of particles based on differences in density is in principle possible, owing to the differences in inertia associated with them. We also discuss the case of significant inertia in which the presence of a small constriction may hinder separation by reducing inertia effects.
Binding sites and electronic states of group 3 metal-aniline complexes probed by high-resolution electron spectroscopy
Authors: Kumari Sudesh , Sohnlein Bradford R. , Hewage Dilrukshi , Roudjane Mourad , Sup Lee Jung , Yang Dong-Sheng
Published: June 2013

Group 3 metal-aniline complexes, M(aniline) (M = Sc, Y, and La), are produced in a pulsed laser-vaporization molecular beam source, identified by photoionization time-of-flight mass spectrometry, and investigated by pulsed-field ionization zero electron kinetic energy (ZEKE) spectroscopy and quantum chemical calculations. Adiabatic ionization energies and several low-frequency vibrational modes are measured for the first time from the ZEKE spectra. Metal binding sites and electronic states are determined by combining the ZEKE measurements with the theoretical calculations. The ionization energies of the complexes decrease down the metal group. An out-of-plane ring deformation mode coupled with an asymmetric metal-carbon stretch is considerably anharmonic. Although aniline has various possible sites for metal coordination, the preferred site is the phenyl ring. The metal binding with the phenyl ring yields syn and anti conformers with the metal atom and amino hydrogens on the same and opposite sides of the ring, respectively. The anti conformer is determined to be the spectral carrier. The ground electronic state of the anti conformer of each neutral complex is a doublet with a metal-based electron configuration of nd2(n + 1)s1, and the ground electronic state of each ion is a singlet with a metal-based electron configuration of nd2. The formation of the neutral complexes requires the nd2(n + 1)s1 ← nd1(n + 1)s2 electron excitation in the metal atoms.
Controlling the absorption spectrum within a thin amorphous silicon layer by using the size dependent plasmonic behaviour of silver nanoparticles
Authors: Mandal Aparajita , Chaudhuri Partha
Published: June 2013

In this paper, we have used Finite Difference Time Domain method for numerically calculating the absorption spectra within a thin layer of hydrogenated amorphous silicon (a-Si:H) with the front surface regularly patterned with spherical Ag nano particles. We have considered a wide range of particle radius (40 nm≤R≤200 nm) for including nano particles that have dipole dominated extinction spectra as well as the particles that can support multipole plasmon resonances. On performing the size variation analysis, constant surface coverage values (S) have been maintained so that the shading effect by the nano particles array will remain same for all particle sizes. We demonstrate that, for effective contribution to the absorption within the a-Si:H layer, there exists a clear distinction between the smaller size nanoparticles which support dipolar resonance and the larger size nano particles capable of producing higher order plasmon modes in terms of S values. The larger particles require much greater coverage than that of smaller particles for efficient plasmonic enhancement. These observations can have considerable importance in designing plasmonic solar cells or other optoelectronic devices that involve various sized Ag nano particles to enhance the optical absorption within an absorber layer.
Comment on “Structure and properties of reduced LaCoO3” [J. Appl. Phys. 44, 5553 (1973)]
Authors: Zhang A. M.
Published: June 2013

A hexagonal crystal lattice with the perovskite structure can be treated as rhombohedral or pseudocubic structure. The publication by Sis and Wirtz [J. Appl. Phys. 44, 5553 (1973)] presented a schematic diagram to explain these relationships, but made a mistake in the hexagonal lattice, which is corrected here.
Modeling of polar nanoregions dynamics on the dielectric response of relaxors
Authors: Ni Y. , Chen H. T. , Shi Y. P. , He L. H. , Soh A. K.
Published: June 2013

A master equation for describing the polar nanoregions (PNRs) dynamics with adaptive-volume-dependent activation energy barrier has been established based on mean field approximation to investigate the anomalous temperature- and frequency-dependent dielectric properties of relaxor ferroelectrics. In the proposed model, the activation energy was correlated with the applied electric field and mean volume of PNRs. By expressing the PNRs mean volume as a function of temperature and pressure, and then fitting it to some existing experimental data, the results obtained reproduced the experimentally observed dielectric response including the broad temperature- and frequency-dependent peaks, frequency shift and dispersion of susceptibility. Finally, it has been found that the pressure and applied electric field led to the decrease of the PNRs relaxation time, and thus the peak of the real part of the dielectric constant was shifted to a lower temperature, which is consistent with the existing experimental data. The present study shows that polar cluster dynamics provides a better understanding of the macroscopic dielectric properties of relaxor ferroelectrics.