bluuebunny/crossref_metadata_2025_split huggingface dataset:
Compact printed coplanar waveguide‐fed ultra‐wideband antenna with multiple notched bands
Authors: Taheri Mohammad Mehdi Samadi , Hassani Hamid R. , Nezhad Sajad Mohammad Ali 
Published: June 2012

AbstractA compact multiband‐notched printed ultra‐wideband (UWB) coplanar waveguide (CPW)‐fed slot antenna is presented. The band notched characteristic is achieved by creating quarter‐wavelength stubs in the ground plane. These stubs act as stop‐band filters along the feed line over certain narrow frequency bands. Addition of each stub to the antenna structure creates an extra independent notch band. Antenna with single, dual, triple, quadruple, and penta notch bands can be created by this technique. The notch bands can be chosen from practical frequency bands such as 3.5 GHz WiMAX, 5.2 and 5.8 GHz WLAN, 7.25–7.75 GHz for the downlink of X‐band satellite communication systems, and ITU at 8.2 GHz band all within the UWB range. Each of the notch bands can be tuned in frequency independently. The antenna has a small size (24 × 27 × 0.8 mm3), and almost stable omnidirectional radiation pattern. The prototype of the antenna is fabricated, and the measured results are in good agreement with the simulations. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2121–2126, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26998
The effects of air stacked on reconfigurable quadratic slots antenna for WiMAX and 4G applications
Authors: Jamlos M. F. , Rahman T. A. , Kamarudin M. R. , Malek M. F. , Jusoh M. 
Published: June 2012

AbstractThis research presents the effects of an air‐stacked configuration on the novel reconfigurable quadratic antenna. The proposed antenna is made feasible by using a feeding line, PIN diodes, and an aperture coupled feeding structure with quadratic slots shape and varied levels of air‐stacked sequence: 0, 5, 10, 15, and 20 mm. Instead of a quadratic slot, it is proven through simulations and measurements that the performance of four types of radiation patterns is greatly influenced by the air‐stacked structure at 2.3 GHz operating frequency. The activation of certain PIN diode switch configuration enables the variety of outcomes of the radiation patterns with different beamwidths and gains at a single time. This novel antenna is competent to shape its radiated beam in terms of gain and half‐power beamwidth up to 12.92 dB (≈ 13 dB) and 110.9°, respectively, with 81.76% of efficiency. The air‐stacked formation also affords a good quality factor, Q, as low as less than 1 (<1) to indirectly indicate that the quality of the antenna in terms of efficiency and gain is outstanding. The proposed antenna has a massive potential to be deployed in WiMAX application in future. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2139–2144, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27000
A compact printed UWB antenna with triple band‐notched characteristics
Authors: Xu Jie , Wang Guangtao 
Published: June 2012

AbstractIn this letter, a compact printed ultra‐wideband antenna with triple band‐notched characteristics is presented. The antenna consists of a circular radiating patch and a 50‐Ω coplanar waveguide transmission line. The triple band‐notched characteristics are obtained by etching two C‐shaped slots on the radiating patch and a pair of symmetric C‐shaped slots on the ground. Simulated and measured results show that this antenna could operate from 2.8 to 12.6 GHz with stable radiation patterns, except triple notched bands at 3.43–3.65, 4.95–5.25, and 5.36–5.85 GHz for rejecting the WiMAX and wireless local area network signals. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2146–2150, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27004
A 60 GHz power amplifier using lange couplers in GaAS 0.15 μm pHEMT process
Authors: Wu Ming‐Wei , Chiang Yen‐Chung 
Published: June 2012

AbstractThis letter proposes a 60 GHz power amplifier (PA) fabricated in GaAs 0.15μm pHEMT process technology.A three‐stage topology with Lange couplers is adopted. The measured results show that the proposed PA achieves a gain of 23 dB and a saturated output power of 14.46 dBm at 63.4 GHz, and its peak power‐added efficiency is 6.9%. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2150–2153, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27015
UWB equiangular spiral antenna for 7.5–40 GHz
Authors: Chernobrovkin R. , Ivanchenko I. , Pischikov V. , Popenko N. 
Published: June 2012

AbstractThe ultrawide‐band antenna with original transformer providing the required electromagnetic matching of the coaxial cable with the small‐size single‐arm equiangular spiral antenna is proposed. The measured input reflection coefficient of the small‐size spiral antenna is less than −10 dB within the frequency band from 7.5 to 40 GHz. The near‐fields, radiation patterns and axial ration within the impedance antenna bandwidth are presented and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2190–2194, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27018
Loading artificial magnetic conductor and artificial magnetic conductor absorber with negative impedance convertor elements
Authors: Ding Yuan , Fusco Vincent 
Published: June 2012

AbstractThe general properties of a frequency selective surface loaded with negative impedance converter (NIC)‐based active loads are discussed from a theoretical perspective.The stability problem associated with NIC circuits embedded in artificial magnetic conductor (AMC) and AMC absorber applications is studied using pole‐zero analysis. The requirements and constraints for achieving stable operation with enhanced bandwidth using negative capacitance as realized by a floating NIC network are derived. Furthermore, it is shown that it is nearly impossible to simultaneously implement a negative capacitor and a negative inductor to such structures. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2111–2114, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27019
UWB printed sectoral monopole antenna with dual polarization
Authors: Ray K. P. , Thakur S.S. , Deshmukh R. A. 
Published: June 2012

AbstractA printed sectoral monopole antenna with ultra wide bandwidth has been proposed. This configuration is formed by chopping off a quarter part of a circular printed disc. The ultra wide bandwidth has been obtained in the frequency range from 1.84 to 11.82 GHz with dual polarization radiation patterns. The experimental and simulated results for this proposed antenna are presented, which are in agreement. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2066–2070, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27039
Ultrawideband monopole antenna for use in a circular cylindrical microwave imaging system
Authors: Halili Khodadad , Ojaroudi Mohammad , Ojaroudi Nasser 
Published: June 2012

AbstractA novel ultrawideband printed monopole antenna for use in a circular cylindrical microwave imaging system is presented.The proposed antenna consists of a square radiating patch and a modified ground plane with an open circuit structure slit and an inverted π‐shaped parasitic structure, which provides a wide usable fractional bandwidth of more than 130% (2.91–14.72 GHz). By cutting an open circuit structure in the ground plane and also by inserting an inverted π‐shaped parasitic structure in the ground plane, additional resonances at 11.5 and 14.2 GHz are excited and hence much wider impedance bandwidth can be produced, especially at the higher band. Unlike other antennas reported in the literature to date, the proposed antenna displays a good omnidirectional radiation pattern even at higher frequencies, and also its radiation efficiency is greater than 87% across the entire radiating band. The designed antenna has a small size of 12 × 18 mm2. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for circular cylindrical microwave imaging systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2202–2205, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27041
Comparing model‐based and model‐free analysis methods for QUASAR arterial spin labeling perfusion quantification
Authors: Chappell Michael A. , Woolrich Mark W. , Petersen Esben T. , Golay Xavier , Payne Stephen J. 
Published: June 2012

AbstractAmongst the various implementations of arterial spin labeling MRI methods for quantifying cerebral perfusion, the QUASAR method is unique. By using a combination of labeling with and without flow suppression gradients, the QUASAR method offers the separation of macrovascular and tissue signals. This permits local arterial input functions to be defined and “model‐free” analysis, using numerical deconvolution, to be used. However, it remains unclear whether arterial spin labeling data are best treated using model‐free or model‐based analysis. This work provides a critical comparison of these two approaches for QUASAR arterial spin labeling in the healthy brain. An existing two‐component (arterial and tissue) model was extended to the mixed flow suppression scheme of QUASAR to provide an optimal model‐based analysis. The model‐based analysis was extended to incorporate dispersion of the labeled bolus, generally regarded as the major source of discrepancy between the two analysis approaches. Model‐free and model‐based analyses were compared for perfusion quantification including absolute measurements, uncertainty estimation, and spatial variation in cerebral blood flow estimates. Major sources of discrepancies between model‐free and model‐based analysis were attributed to the effects of dispersion and the degree to which the two methods can separate macrovascular and tissue signal. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Impact of aging on the progression of neuropathy after liver transplantation in transthyretin Val30Met amyloidosis
Authors: Koike Haruki , Hashimoto Rina , Tomita Minoru , Kawagashira Yuichi , Iijima Masahiro , Nakamura Tomohiko , Watanabe Hirohisa , Kamei Hideya , Kiuchi Tetsuya , Sobue Gen 
Published: June 2012

AbstractIntroduction: Information related to the long‐term follow‐up of neuropathy in patients with familial amyloid polyneuropathy after liver transplantation is still scarce.Methods: We describe the neuropathic features of 3 patients with the transthyretin Val30Met mutation. Each patient underwent liver transplantation at an early stage of neuropathy, as indicated by the absence of motor dysfunction and relative preservation of myelinated fibers in sural nerve biopsy specimens.Results: Although the patient with late‐onset disease (at age 60 years) presented with the least amount of amyloid deposition, he had neuropathic progression after liver transplantation. An older early‐onset (at age 40 years) patient reported a slight exacerbation of both somatic and autonomic neuropathic symptoms 10 years after transplantation. However, the younger early‐onset (at age 28 years) patient did not exhibit characteristics suggestive of neuropathy 7 years after transplantation.Conclusion: Aging may determine the progression of neuropathy after liver transplantation. Muscle Nerve, 2012
THE POLITICAL ECONOMY OF GREEN GROWTH: CASES FROM SOUTHERN AFRICA
Authors: Resnick Danielle , Tarp Finn , Thurlow James 
Published: June 2012

SUMMARYThe concept of Green Growth implies that a wide range of developmental objectives, such as job creation, economic prosperity and poverty alleviation, can be easily reconciled with environmental sustainability. This article, however, argues that rather than being win–win, Green Growth is similar to most types of policy reforms that advocate the acceptance of short‐term adjustment costs in the expectation of long‐term gains. In particular, Green Growth policies often encourage developing countries to redesign their national strategies in ways that might be inconsistent with natural comparative advantages and past investments. In turn, there are often sizeable anti‐reform coalitions whose interests may conflict with a Green Growth agenda. We illustrate this argument by using case studies of Malawi, Mozambique and South Africa, which are engaged in development strategies that involve inorganic fertilizers, biofuel production and coal‐based energy, respectively. Each of these countries is pursuing an environmentally suboptimal strategy but nonetheless addressing critical development needs, including food security, fuel and electricity. We show that adopting a Green Growth approach would not only be economically costly but also generate substantial domestic resistance, especially among the poor. Copyright © 2012 John Wiley & Sons, Ltd.
ENVIRONMENTAL MAINSTREAMING: THE ORGANISATIONAL CHALLENGES OF POLICY INTEGRATION
Authors: Nunan Fiona , Campbell Adrian , Foster Emma 
Published: June 2012

SUMMARYMainstreaming has been adopted internationally as a key approach to promoting environmental concerns and opportunities in national plans and strategies, as well as in sectoral policies and plans. As the climate change response begins to look to mainstreaming as a way forward for adaptation, lessons should be learnt from the environmental mainstreaming experience on the forms of organisational arrangements adopted. From an analysis of experience in a range of southern countries, the article uses a framework of vertical and horizontal organisational arrangements for policy integration to assess which organisational forms have been adopted and with what implications. The review found a mix of experience, with strong political commitment seeming to support a vertical approach to organisational integration, with a lead, overarching agency, as opposed to a more horizontal approach with the ministry responsible for the environment leading. The theory and analysis suggests that a more promising approach to facilitate effective mainstreaming might be to combine elements of vertical and horizontal arrangements, at least over the medium term, where there is strong central commitment and capacity for sustained implementation. Copyright © 2012 John Wiley & Sons, Ltd.
COMPLEMENTING THE LOCAL AND GLOBAL: PROMOTING SUSTAINABILITY ACTION THROUGH LINKED LOCAL‐LEVEL AND FORMAL SUSTAINABILITY FUNDING MECHANISMS
Authors: Merritt Amy , Stubbs Tristan 
Published: June 2012

SUMMARYThis article explores some of the challenges associated with financing sustainability action at the local level, using South Africa and the UK as case studies. Formal climate finance, including flows through multilateral development banks and private sector investor markets, has been criticised for failing effectively to link global financial interests to community needs and priorities. We discuss how a number of new financial innovations, including TimeBanking, community currencies, community share schemes, and peer‐to‐peer lending could help to bridge this gap. In particular, we explore how such financial innovations could be employed to support a more community‐driven allocation of sustainability financing that prioritises local social and environmental benefits. We suggest that grassroots financing mechanisms have the potential to account for the social dimension in mobilising resources in a green economy as well as supporting civil society and local governments to develop greater decision‐making around the mobilisation and allocation of sustainability resourcing. Further, by bringing together the local and the global, sustainability financing instruments could also help to create synergies and constructive partnerships among public administrations, markets, and society for finding creative and locally appropriate solutions to promote sustainable development. Copyright © 2012 John Wiley & Sons, Ltd.
High levels of fetal DNA are associated with increased risk of spontaneous preterm delivery
Authors: Jakobsen Tanja R. , Clausen Frederik B. , Rode Line , Dziegiel Morten H. , Tabor Ann 
Published: June 2012

ABSTRACTObjectiveTo assess whether spontaneous preterm delivery can be predicted from the amount of cell free fetal DNA (cffDNA) as determined by routine fetal RHD genotyping at 25 weeks’ gestation.Study designCohort study including RhD negative women participating in a routine RHD screening programme. A standard dilution curve was used to quantify the amounts of cffDNA. Values above the 95th centile for the study population defined high levels of cffDNA.ResultsWe found a highly significant association between preterm delivery and cffDNA levels above the 95th centile (p = 0.002). Using logistic regression, women with high levels of cffDNA had an odds ratio of 6.3 (95% confidence interval: 1.9–20.9) for preterm delivery before 37 weeks and an odds ratio for delivery before 34 weeks of 16.6 (95% confidence interval: 3.2–84.7) when adjusting for gestational age at sampling, body mass index and previous miscarriages/terminations of pregnancy.ConclusionHigh levels of cffDNA at 25 weeks are associated with increased risk of spontaneous preterm delivery. © 2012 John Wiley & Sons, Ltd.
Parents' role in the academic motivation of students with gifts and talents
Authors: Garn Alex C. , Matthews Michael S. , Jolly Jennifer L. 
Published: June 2012

AbstractParents play a key role in developing their children's academic motivation, and parents of children with gifts and talents also may face additional parenting challenges that are less commonly faced by parents of average‐ability learners whose needs are more readily met in the school setting. School psychologists may be charged with addressing these issues, despite having little or no training on the needs of families of high‐ability learners. We use the lens provided by the self‐determination theory of motivation to consider how social–environmental climates created by parents can promote or impede the academic motivation of students with gifts and talents. © 2012 Wiley Periodicals, Inc.
Gendered practices in the education of gifted girls and boys
Authors: Kerr Barbara A. , Vuyk M. Alexandra , Rea Chistopher 
Published: June 2012

AbstractGifted girls and gifted boys are more alike than they are different, although researchers remain fascinated with sex differences. Small differences between gifted boys and girls in achievements, interests, careers, and relationships can become exaggerated through gendered educational practices. Kindergarten “red‐shirting'' of boys and the denial of early admission to girls can cause gifted children to be out of step throughout their academic careers. When gifted children are not actively encouraged to participate in talent searches and after‐school and summer programs, whether because of overprotection of girls or the insistence on athletic activities at the expense of academic activities for boys, they lose the opportunity for challenge, friendships, and community. When boys are not supported in their interests in creative careers and girls are not supported in their interests in science, technology, engineering, and mathematics careers, they may enter occupations that will not offer them the sense of purpose and meaning they might have otherwise had. It is in the area of gender relations, however, that long‐term consequences of gendered practices are most apparent for gifted individuals because both gifted boys and girls need to plan for balancing family and career. © 2012 Wiley Periodicals, Inc.
Motivation and gifted students: Implications of theory and research
Authors: Clinkenbeard Pamela R. 
Published: June 2012

AbstractAn analysis of contemporary motivation theories reveals implications for gifted and talented students. The expectancy‐value framework, intrinsic‐extrinsic motivation theories, goal orientations, self‐efficacy and other self‐perceptions, and attribution theory are described and discussed with respect to implications for the psychology and education of gifted and talented students. Illustrative empirical research on motivation and gifted students is presented, and a model of classroom motivation factors is provided as a practical structure within which to consider instructional practices with this population. © 2012 Wiley Periodicals, Inc.
Dynamical stabilization and time in open quantum systems
Authors: Rotter I. 
Published: June 2012

AbstractThe meaning of time in an open quantum system is considered under the assumption that both, system and environment, are quantum mechanical objects. The Hamilton operator of the system is non‐Hermitian. Its imaginary part is the time operator. As a rule, time and energy vary continuously when controlled by a parameter. At high level density, where many states avoid crossing, a dynamical phase transition takes place in the system under the influence of the environment. It causes a dynamical stabilization of the system what can be seen in many different experimental data. Due to this effect, time is bounded from below: the decay widths (inverse proportional to the lifetimes of the states) do not increase limitless. The dynamical stabilization is an irreversible process.
Exceptional points for logic operations at the molecular level
Authors: Jaouadi A. , Desouter‐Lecomte M. , Lefebvre R. , Atabek O. 
Published: June 2012

AbstractWhen a molecule is exposed to a laser field which leads to dissociation, all field‐free vibrational bound states become resonances, with complex eigenenergies described by non Hermitian quantum mechanics. It is possible to produce the coalescence of pairs of such eigenenergies, with appropriate choices of laser frequency and intensity, these particular values defining an exceptional point. We review some of the aspects of this very special situation. There are two principal characteristics of the adiabatic dynamics of a pair of vibrational states when the laser pulse encloses their exceptional point: the complete population inversion and the different type of transient resonance states. According to clock or anticlockwise loops in the frequency‐intensity plane, the resonances can either be of Shape or Feshbach‐type. This leads to a variety of different responses according to the initial state of the molecule that can be used to build a finite state logic machine based on the exceptional points of molecular photodissociation. The molecule chosen for this study is Na2.
Entanglement of identical particles and the detection process
Authors: Tichy M.C. , de Melo F. , Kuś M. , Mintert F. , Buchleitner A. 
Published: June 2012

AbstractWe introduce detector‐level entanglement, a unified entanglement concept for identical particles that takes into account the possible deletion of many‐particle which‐way information through the detection process. The concept implies a measure for the effective indistinguishability of the particles, which is controlled by the measurement setup and which quantifies the extent to which the (anti‐)symmetrization of the wave‐function impacts on physical observables. Initially indistinguishable particles can gain or loose entanglement on their transition to distinguishability, and their quantum statistical behavior depends on their initial entanglement. Our results show that entanglement cannot be attributed to a state of identical particles alone, but that the detection process has to be incorporated in the analysis.