bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on ultrawideband filters using stub‐loaded circular and triangular resonators
Authors: Gupta Ravi Dutt , Abegaonkar Mahesh P. , Basu Ananjan , Koul Shiban K.
Published: August 2008

Compact UWB bandpass filters using stub‐loaded ring and triangular resonators fed with capacitive‐ended interdigital coupled lines are proposed. The proposed structures are fed with capacitive‐ended interdigital coupled lines. The measured insertion loss for ring resonator filter is 1.0 dB and that for triangular resonator is 2.0 dB with corresponding group delays of 0.6 and 0.3 ns, respectively. These filters show sharp transitions at the edges of the UWB passband and improved out‐of‐band performance. The simulated and measured results are in good agreement and satisfy the FCC mask for indoor applications. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2917–2922, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23834
High‐gain multilayer 2×2 antenna array for wireless applications
Authors: Gupta R. K. , Kumar G.
Published: August 2008

This article proposes an efficient high‐gain multilayer 2×2 antenna array for wireless applications. The prototype antenna consists of a microstrip antenna which feeds 2×2 array of square parasitic patches fabricated on a low‐cost easily available FR4 superstrate. The patches on superstrate are suspended in air at λ0/2. The structure is designed, fabricated, and tested. The measured VSWR is < 2 over 5.725–5.875 GHz frequency band. The proposed antenna with 2×2 array of square parasitic patches provides 80% efficiency and SLL of −24 dB with an associated gain of 14.9 dB. The proposed structure can be packaged inside an application platform. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2911–2917, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23835
A novel ultra‐wideband monopole antenna with two symmetrical strips
Authors: Song Hyo W. , Park Jong K. , Yoo Jin H.
Published: August 2008

In this article, we have described a novel ultra‐wideband (UWB) monopole antenna with two symmetrical strips for wireless UWB communications. The proposed antenna consists of a center monopole, two symmetrical strips having one step on the strip, and CPW feeding. Three techniques (one monopole and two strips, symmetrical structure, and step on the strip) are used to produce the multiple resonance and low dispersion. The proposed UWB antenna has an omnidirectional radiation pattern, UWB, compact size, almost flat gain and linear phase, and low cost. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2845–2848, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23838
A compact filter‐combined ultra‐wide band antenna for UWB applications
Authors: Lee Jung N. , Park Jong K. , Choi Il H.
Published: August 2008

We have proposed a compact filter‐combined ultra‐wide band antenna for the use of DS‐UWB low band or MB‐OFDM lower three bands (3.1–5.2 GHz). The designed antenna has a microstrip‐fed trapezoidal radiating patch, UWB band pass filter using the dumbbell‐shaped DGS (defected ground structure), and IDC (interdigital capacitor): two steps for impedance matching, and microstrip feeding. Three kinds of prototypes (trapezoidal UWB antenna, UWB band pass filter, and the compact filter‐combined ultra wideband antenna) are fabricated and measured. The designed antenna has the figure‐of‐eight radiation pattern, wide bandwidth, and negligible dispersion over the operating frequency band. Details of the proposed antenna design and the simulated and measured results are presented and discussed. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2839–2845, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23839
Uniplanar harmonic suppressed compact rat‐race couplers
Authors: Krishna Velidi Vamsi , Kanti Mandal Mrinal , Bhattacharya Amitabha
Published: August 2008

A design of a miniaturized rat‐race coupler with higher‐order harmonic suppression is presented in this article. The slow wave effect and stopband produced by a shunt open‐stub is utilized to miniaturize the occupying area and suppress higher order harmonics, respectively. Design guidelines are obtained using a transmission line model. A prototype coupler has been fabricated in microstrip line to validate the theoretical predictions. The fabricated coupler occupies 18.4% area of that of a conventional coupler. At the same time, the second to tenth harmonics are suppressed by at least 15 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2812–2814, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23840
Broadband internal antenna by combination of a loop type antenna and a shorted monopole
Authors: Bin Park Su , Min Kim Sung , Geun Yang Woon
Published: August 2008

Broadband internal antenna by combination of a loop type antenna and a shorted monopole is proposed for GSM/GPS/DCS/PCS/UMTS/WiBro/WLAN applications. The proposed antenna shows wide impedance bandwidths as well as good radiation patterns and high antenna gains, despite very small volume. And wide impedance bandwidth can be achieved without increasing the implementation complexity compared with that of existing antennas. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2810–2812, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23841
Analysis of propagation loss of metallic photonic crystal waveguides
Authors: Kokubo Yoshihiro
Published: August 2008

Metallic waveguides can be constructed with sidewalls consisting of metallic rods instead of sheets. The attenuation constants and bandwidths of such waveguides are calculated for a fixed cutoff frequency while the radii of the metallic rods are varied. The propagation losses are found to decrease when the radii of the rods is increased. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2942–2945, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23844
Study on the induced current measurement in bridgewire EED
Authors: Mei Shu‐Gang , Wang Tao , Yin Fei , He Jun‐Fang , Ruan Chi , Wu Lei‐Xue , Zhao Tuan
Published: August 2008

In this study, an infrared optical fiber light splitting system is proposed for the measurement of induced current in bridgewire electroexplosive device (EED). The system includes infrared optical fiber that eliminates interference from external electromagnetic radiation, a lens assembly that optimally focuses the infrared energy from the bridgewire to the infrared fiber and no‐touch the bridgewire, two infrared detectors that measure the middle and near infrared radiation from bridgewire, respectively, and a photomodulator and phase‐locked amplifiers that depress the noises. The experimental results suggest that the induced current in bridgewire can be an accurate determination by using this system, and the measurement error is less than 0.0154 mA in high‐temperature region. A new method is provided to confirm the safety and reliability of the electric ignition system in electromagnetic environment. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2833–2835, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23845
Compact dual‐band filter design using crossly coupled λ/4 SIRs embedded with spur‐line for WLAN applications
Authors: Chen Pow‐Wen , Ho Min‐Hua , Hong Wanchu
Published: August 2008

This article presents a compact dual‐band bandpass filter (BPF) design using λ/4 stepped impedance resonators (SIRs) embedded with spur‐line for the WLAN applications. The filter covers both the operating frequencies of 2.45 GHz and 5.2–5.8 GHz. The crossly coupled mechanism is used in the filter design to provide attenuation poles by the passband edges for enhancing the signal selectivity and increasing stopband rejection levels. The tapped‐line is incorporated in feed structure to save the circuit space. The spur‐line is embedded in each I/O SIRs to push the upper stopband limit to a higher frequency. Experiments are conducted to verify the circuit performance. A good agreement is observed between the simulation and the measurement. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2807–2810, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23846
A magnetic field controlled negative‐index microwave lens
Authors: Petrov R. V. , Pandey R. , Srinivasan G. , Bichurin M. I.
Published: August 2008

A three‐dimensional lens with magnetic field control of the index of refraction and focal length has been designed and characterized over 2‐18 GHz. The lens is made of a lattice of cross‐wire resonators and ferrite cubes. For the lattice without the ferrite cubes, a refractive index n ≈ −1 is measured at 11.25 GHz. With the introduction of ferrite cubes in the lattice, n could be tuned over the range −1.2 to +1.8 for nominal bias magnetic fields H. The focal point for the lens with n ≈ −1, for example, could be displaced by 2 cm by tuning H from 4100 to 4125 Oe. Theoretical estimates of the lens characteristics are in agreement with the data. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2804–2807, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23847
396 fs pulse from an asynchronous mode‐locked erbium fiber laser with 2.5 12 GHz repetition rate
Authors: Boncristiano E. S. , Saito L. A. M. , De Souza E. A.
Published: August 2008

We have demonstrated an Erbium fiber laser hybridly mode‐locked by a phase modulator in conjunction with intracavity soliton effect producing pulses as short as 396 fs at 10 GHz. The laser repetition rate is variable from 2 to 12 GHz keeping pulses with duration shorter than 500 fs in this range. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2994–2996, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23849
AlGaN/GaN‐based SAW delay‐line oscillators
Authors: Jesús Grajal  , Calle Fernando , Pedrós Jorge , Martínez‐Chacón José Luis , Jiménez Ana
Published: August 2008

Surface acoustic wave filters fabricated on AlGaN/GaN heterostructures allow the control of their insertion losses through external voltages applied to the interdigital transducers. A novel SAW delay‐line oscillator based on an AlGaN/GaN‐on‐sapphire SAW device with an oscillation frequency of 475 MHz has been developed. Its waveform compression is controlled by varying the insertion losses of the active SAW filter. A small temperature coefficient of delay of 17.5 ppm/°C has been obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2967–2970, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23852
Characteristics of GaAs transformers for RFIC applications
Authors: Meng Chinchun , Teng Ya‐Hui , Syu Jin‐Siang , Lin Yi‐Chen , Jhong Jhin‐Ci , Yen Ying‐Chieh
Published: August 2008

In this article, stacked transformers, coupling stacked transformers, interleave transformers, and symmetrical transformers on GaAs substrate are systematically studied. Two kinds of stacked transformer are under study. One has the symmetrical electric property while the other one has a better quality factor for the primary port. The stack transformers have achieved the highest coupling coefficient (∼0.9) at the cost of lower self‐resonance frequency. The interleave transformers have the identical electrical properties for the primary and the secondary ports. However, the layout is incompatible with the differential operation. On the other hand, the symmetrical transformer is compatible with the differential operation and can have the center‐tapped biasing option. The data established here provides a useful design library for the GaAs RFIC. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2937–2942, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23853
CMOS bandpass filters for 77 GHz automotive radar systems
Authors: Nan Lan , Mouthaan Koen , Xiong Yong‐Zhong , Shi Jinglin , Chander Rustagi Subhash , Brinkhoff James , Ooi Ban‐Leong
Published: August 2008

This article presents a systematic design and measurement of narrow and wide bandpass filters at 77 GHz in a 0.18‐μm CMOS technology. Various bandwidths from 10 to 50% are realized using a parallel coupled line topology in a thin film microstrip configuration. The relationship between the insertion loss and the 3‐dB bandwidth of the filters is experimentally determined for this technology. The result is also compared with theoretical prediction. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2934–2937, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23854
A directive dual‐band and dual‐polarized antenna with zero index metamaterial
Authors: Weng Zi‐Bin , Song Yue , Jiao Yong‐Chang , Zhang Fu‐Shun
Published: August 2008

A novel directive dual‐band and dual‐polarized microstrip antenna with ZIM is presented. An averaging effect over constituent materials of the metamaterial structure yields an effective permittivity that approaches zero at dual band with different polarizations, and then it results in a metamaterial with zero index of refraction and the radiation energy of this antenna is congregated. The experimental results show that this method is effective, and this structure can greatly increase the gain at dual frequencies. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2902–2904, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23855
A compact broadband circularly polarized composite antenna with wide beamwidth
Authors: Houjun  , Sun  , Shi Lei , Li Jingtao
Published: August 2008

A compact composite antenna applied to the satellite movable termination is presented in this article. The antenna unit is composed of a monofilar conical helix and a radial omnidirectional waveguide antenna with eight vertical metal rods. From the viewpoint of widening the circularly polarized (CP) beamwidth in vertical plane and frequency bandwidth, these components are unified as a single composite antenna. Both the simulated and measured results show that the broad CP beamwidth can be obtained over the frequency range from 2.3 to 3.3 GHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2973–2975, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23857
Five‐port receiver with improved sensitivity
Authors: de Sousa Fernando Rangel , Huyart Bernard
Published: August 2008

This article reports the architecture of a five‐port receiver without vector base circuit generators in which three antennas provide three phase‐shifted copies of the received signal. A 2.4‐GHz prototype was implemented for concept proofing, and the measurements point to a sensitivity improvement of 6 dB with respect to comparable classic five‐port receivers. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2945–2947, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23858
The 5.8‐GHz fully integrated low‐power low‐phase‐noise CMOS LC VCOs using RC noise‐filtering technique
Authors: Lee Jen‐How , Chen Chi‐Chen , Lin Yo‐Sheng
Published: August 2008

In this work, two 5.8‐GHz fully integrated LC differential voltage‐controlled oscillators (VCOs) using standard 0.18 μm CMOS technology were implemented. One of them adopted a standard differential inductor (STD VCO). The other (PPGS VCO) comprised the same layout except that PPGS (poly‐silicon partial pattern‐ground‐shields) was added beneath its differential inductor for Q‐factor enhancement. Low‐power consumption was achieved by maximizing the equivalent parallel resistance (RP) of the LC tank by layout optimization. In addition, low‐phase noise was achieved mainly by adding two parallel capacitors to the cross‐coupled transistors and a resistor (Rfilter) to the biasing transistor for suppressing the noise coming from the current source. The STD VCO achieved a wide‐tuning‐range of 10.3% (from 5.26 GHz to 5.802 GHz) with a low‐power dissipation of 3.02 mW. The measured phase noise was −118.25 dBc/Hz at 1‐MHz offset. The corresponding figure‐of‐merit (FOM) was −188.72 dBc/Hz, better than those of the reported state‐of‐the‐art CMOS LC VCOs in 5‐GHz‐band. The chip area was only 508 × 595 μm2excluding the test pads. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2907–29117, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23859
Analysis and experiment for drain bias dependence of IMD sweet spots in GaN HEMT power amplifier
Authors: Lee Yong‐Sub , Lee Mun‐Woo , Jeong Yoon‐Ha
Published: August 2008

In this article, we propose the drain bias dependency on the intermodulation distortion (IMD) sweet spots of a gallium nitride (GaN) high‐electron mobility transistors power amplifier (PA). Using the mathematical approach by the IDS–VGS characteristic curves and two‐tone distortion products, the positions of the IMD sweet spots according to drain bias as well as gate bias and input power are predicted and well‐matched with the measured results. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2836–2839, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23863
Erratum: Bode and Fano impedance matching
Authors: Hansen R. C.
Published: August 2008

Originally published Microwave Opt Technol Lett 50 (2008), 875–877.
Spectrum separation resolves partial‐volume effect of MRSI as demonstrated on brain tumor scans
Authors: Su Yuzhuo , Thakur Sunitha B. , Sasan Karimi , Du Shuyan , Sajda Paul , Huang Wei , Parra Lucas C.
Published: September 2008

Magnetic resonance spectroscopic imaging (MRSI) is currently used clinically in conjunction with anatomical MRI to assess the presence and extent of brain tumors and to evaluate treatment response. Unfortunately, the clinical utility of MRSI is limited by significant variability of in vivo spectra. Spectral profiles show increased variability because of partial coverage of large voxel volumes, infiltration of normal brain tissue by tumors, innate tumor heterogeneity, and measurement noise. We address these problems directly by quantifying the abundance (i.e. volume fraction) within a voxel for each tissue type instead of the conventional estimation of metabolite concentrations from spectral resonance peaks. This ‘spectrum separation’ method uses the non‐negative matrix factorization algorithm, which simultaneously decomposes the observed spectra of multiple voxels into abundance distributions and constituent spectra. The accuracy of the estimated abundances is validated on phantom data. The presented results on 20 clinical cases of brain tumor show reduced cross‐subject variability. This is reflected in improved discrimination between high‐grade and low‐grade gliomas, which demonstrates the physiological relevance of the extracted spectra. These results show that the proposed spectral analysis method can improve the effectiveness of MRSI as a diagnostic tool. Copyright © 2008 John Wiley & Sons, Ltd.
k‐space analysis of point‐resolved spectroscopy (PRESS) with regard to spurious echoes in in vivo1H MRS
Authors: Starck G. , Carlsson Å. , Ljungberg M. , Forssell‐Aronsson E.
Published: September 2008

The spurious echo artefact, not uncommon in 1H MRS in the brain, comes from refocusing outer volume signal. Application of MRS in small volumes in susceptibility‐affected regions often results in large shim gradients. The artefact problem is accentuated when the global effect of the shim gradient shifts the water resonance outside the water suppression band in the outer volume. This scenario brings the issue of spurious echoes once again to the fore. In this paper, spurious signals of the point‐resolved spectroscopy (PRESS) sequence are analysed using the concept of k‐space. This new approach facilitates a more geometrical view of the problem, well suited for studying the effect of gradient spoiling and refocusing of signal. Several spoiling options are shown, and the probability of the global effects of shimming being a primary cause of the artefact is discussed. Fourier transform analysis of realistic slice profiles, combined with the k‐space description of spurious echoes, shows that unsuppressed water signal in outer regions greatly increases the demands on spoiling. Gradient spoiling adequate for artefact suppression at a given size of MRS volume may not be sufficient at a smaller size. Several ways to improve PRESS measurements with regard to suppression of spurious signal are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
From acene to graphene spectrum of π electrons with the use of the Green's function
Authors: Malysheva Lyuba , Onipko Alexander
Published: September 2008

The origin of the spectrum of π electrons that results from the coupling of N 𝒩 ‐long acenes via C‐C covalent bonding has been traced with the use of the Green function formalism.

Exact expressions of acene and graphene Green's functions, which are useful for analysis of the electronic properties of these macromolecules, are obtained and advanced to a form suitable for instructive applications. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanomechanical radio transmitter
Authors: Weldon J. , Jensen K. , Zettl A.
Published: September 2008

We explore a design possibility for a highly integrated nanoscale radio transmitter, where the key functional component is a mechanically vibrating electrically charged beam. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wide‐range optical spectra of carbon nanotubes: a comparative study
Authors: Kamarás K. , Pekker Á. , Bruckner M. , Borondics F. , Rinzler A. G. , Tanner D. B. , Itkis M. E. , Haddon R. C. , Tan Y. , Resasco D. E.
Published: September 2008

We present optical spectra from the far infrared through the ultraviolet spectral region of freestanding transparent carbon nanotube films: single‐, double‐ and multiwalled, and containing varying amounts of tubes of different chirality. By comparing the spectral features in the far infrared and the near infrared/visible, we can estimate the metallic/semiconducting content. We show by spectroscopic methods that doping the tubes increases both the conductivity and the transparency for visible light.We also discuss the influence of sample preparation and subsequent treatment on application possibilities. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
La@C82 as a spin‐active filling of SWCNTs: ESR study of magnetic and photophysical properties
Authors: Ćirić Luka , Pierzchala Katarzyna , Sienkiewicz Andrzej , Magrez Arnaud , Náfrádi Bálint , Alexander Duncan , Warner Jamie , Shinohara Hisanori , Ruemmeli M. H. , Pichler T. , Briggs G. Andrew D. , Forró László
Published: September 2008

Electron microscopy (TEM) and electron spin resonance (ESR) were applied to characterize lanthanum metallo‐fullerene (La@C82)‐filled peapods. The peapods were prepared by encapsulation of La@C82 in SWCNTs, which were obtained by laser ablation technique in the presence of non‐magnetic catalysts Pt: Rh: Re. Empty fullerenes, C60, were used as separators for the spin‐active La@C82. TEM analysis confirmed filling of peapods with both C60 and La@C82 molecules. ESR spectra acquired in the temperature range from 5 K to 295 K provided indirect evidence of encapsulation of the spin‐active La@C82 in carbon nanotubes and pointed to marked differences in magnetic properties of peapods as a function of the relative concentration of La@C82. Preliminary ESR studies of the photo‐physical properties of La@C82 in CS2 revealed that, under illumination with white light, La@C82 neither generated singlet oxygen nor was photoactive against a paramagnetic target, nitroxide radical (TEMPO). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibrational properties of four consecutive carbon picotubes
Authors: Rosenkranz Nils , Machón María , Herges Rainer , Thomsen Christian
Published: September 2008

Four different picotubes have been synthesized up to now. These highly symmetric, ringlike hydrocarbons are closely related to the smallest armchair nanotubes available. We investigate vibrational properties of the different picotubes using first principles calculations and polarization‐dependent Raman spectroscopy. Our results emphasize the strong relationship between picotubes and nanotubes.

In this context, two features in the picotube spectra are of particular interest: The high‐energy bands and breathing‐like modes. Vibrational patterns calculated for the high‐energy modes of picotubes are similar to the axial and transversal high‐energy vibrations of armchair nanotubes. Concerning the radial breathing modes of picotubes, our calculations suggest a d–1‐dependence of the radial breathing mode (RBM) frequency, which is again in analogy to nanotubes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of Phragmites japonica on a sandbar of regulated river: morphological adaptation of the plant to low water and nutrient availability in the substrate
Authors: Asaeda Takashi , Siong Kian , Kawashima Takayuki , Sakamoto Kentaro
Published: September 2008

The construction of upstream dams regulates flood magnitudes, reduces the inundation frequency of the riparian zones and curtails the discharge of sediments to the downstream. Adaptation of a Phragmites japonica colony growing at a rarely flooded sandbar (1.4 × 0.25 km) was investigated. Above‐ and belowground biomass was sampled, together with litters on the ground surface of a quadrat and soil in the rhizosphere. Five sampling locations were selected with three locations located in sandy and two in stony areas. The results showed the total biomass and the ratio of above‐ to belowground biomasses were larger at the sandy sites than the stony sites. However, the fraction of root biomass (i.e. root to rhizome ratio) in the belowground biomass at the stony sites was higher than that at the sandy sites. Higher aboveground and total plant biomass in the sandy areas was because the plants had better access to water and nutrients than plants growing in stony beds. A higher proportion of root biomass, at the expense of rhizome biomass, in the belowground biomass of plant growing in stony sites was due to the difficulty in accessing water and inorganic nutrients. The ratios of nitrogen (N) to phosphorus (P) in the plant tissues were mostly between 5 and 10, indicating that plant growth was N limited. Low ratios of total N (TN) to total P (TP) were also recorded in soil samples, where TN was 300–700 mg/kg and TP was 300–350 mg/kg. A wide phenotypic plasticity observed in P. japonica was an importance factor to maximize the plant survival and fitness in frequently disturbed habitats, and this plasticity was the result of both true adjustment and ontogenetic drift. A mitigation effort, aimed to prevent coarsening of the riverbed by supplying sand to the downstream, can actually advance the development of P. japonica colonies. Copyright © 2008 John Wiley & Sons, Ltd.
Socially sustainable work organizations: A chaordic systems approach
Authors: Kira Mari , Eijnatten Frans M. van
Published: September 2008

This paper outlines an approach to socially sustainable work organizations. Socially sustainable work organizations have a dynamic ability to function both by repeating accustomed and by devising innovative solutions, and they maintain this operational viability by promoting the functional capabilities of their stakeholders. The organizational and stakeholder functional capabilities are founded on complexity stemming from the simultaneous uniqueness and integration of resources. It is argued that traditional socio‐ technical systems (STSs) approaches do not offer optimal foundations for achieving sustainability. Instead, a migration into chaordic systems thinking (ChST) is proposed. It is concluded that to promote social sustainability, a work organization has to be understood as a holon system in which development can only take place when also its members grow in their interior and exterior complexities. Complexity development is outlined as an emergent process; the importance of ‘un‐learning’ or dissipation is also explored. Copyright © 2008 John Wiley & Sons, Ltd.
Robert Browne and Full Employment
Authors: Anderson Bernard E.
Published: September 2008

Among the valuable contributions Robert Browne made in his career was the role he played in shaping the “Equal Opportunity and Full Employment Bill of 1974” that was introduced by Congressman Augustus Hawkins of California. Browne defined full employment as “a condition in which all persons willing and able to work, no matter what their race, gender, or national origin would be guaranteed a job”. In his view, if the private sector was unable to produce full employment, the government should act as the employer of last resort. Language in support of that view was included in the Hawkins bill. Robert Browne believed only a national policy to achieve that goal would eliminate racial disparities in employment and unemployment—a long term reality in the American labor market. The 1974 Hawkins bill was met with only tepid Congressional support, little notice from civil rights leaders, and no response from the business community. Little was done to advance full employment legislation until Senator Hubert H. Humphrey of Minnesota embraced the cause in 1975. Negotiations with Congressman Hawkins led to the development of the “Full Employment and Balanced Growth Act of 1975,” a legislative measure to replace the Employment Act of 1946. The new bill was commonly known as the Humphrey–Hawkins Full Employment Bill. Robert Browne offered far less support for the new bill than for the original full employment bill introduced by Mr. Hawkins. The Humphrey Hawkins Bill failed to provide explicitly a job guarantee for all workers, and included an inflation target to make price stability co-equal with full employment as a national policy objective. The Humphrey–Hawkins Bill was enacted into law in 1978, and remains the nation's policy dictum on full employment to this day.
Gratitude and subjective well‐being in early adolescence: Examining gender differences
Authors: Froh Jeffrey J. , Yurkewicz Charles , Kashdan Todd B.
Published: August 2008

Gratitude was examined among 154 students to identify benefits from its experience and expression. Students completed measures of subjective well‐being, social support, prosocial behavior, and physical symptoms. Positive associations were found between gratitude and positive affect, global and domain specific life satisfaction, optimism, social support, and prosocial behavior; most relations remained even after controlling for positive affect. Gratitude demonstrated a negative relation with physical symptoms, but not with negative affect. Relational fulfillment mediated the relation between gratitude and physical symptoms. Gratitude demonstrated strong relations with the following positive affects: proud, hopeful, inspired, forgiving, and excited. The relation between gratitude and family support was moderated by gender, indicating that boys, compared with girls, appear to derive more social benefits from gratitude. Strengths, limitations, and implications are discussed.
Pain and somatosensory findings in patients 3 years after total hip arthroplasty
Authors: Nikolajsen Lone , Kristensen Anders D. , Thillemann Theis M. , Jurik Anne Grethe , Rasmussen Thomas , Kehlet Henrik , Jensen Troels S.
Published: August 2008

Background: Chronic hip pain after total hip arthroplasty (THA) is a significant problem, but the aetiology remains unclear.

Aims: To determine sensory function in patients with chronic hip pain 3 years after THA. Patients without hip pain after THA served as controls.

Methods: Eighteen patients with chronic hip pain and 18 controls without chronic hip pain were recruited from a previous questionnaire study about hip pain after total hip arthroplasty. All participants answered questions about pain and mental vulnerability and underwent clinical examination followed by quantitative sensory testing (brush‐evoked allodynia, pinprick hyperalgesia, mechanical and thermal thresholds).

Results: Brush‐evoked allodynia was present in 4 patients with hip pain (P=0.1) and pinprick hyperalgesia (P=0.02) was more frequent in patients with chronic hip pain. Mechanical and thermal thresholds were similar in patients and controls. Patients with chronic hip pain had higher scores on the mental vulnerability scale (P<0.001). Chronic hip pain was significantly associated with low back pain (P=0.002).

Conclusions: We found signs of hypersensitivity on the operated side, which was more prominent in patients with pain. Pain referred from the back or deeper structures in the hip seems to play a role for the pain in subgroups of patients. In addition, chronic hip pain was associated with mental vulnerability.
Sex differences in perceptions of pain coping strategy usage
Authors: Keogh Edmund , Denford Sarah
Published: September 2008

Sex differences are generally found in the perception and experience of pain, with women reporting more intense and frequent pain than men. One reason why such differences may occur has been linked to socially‐acquired gender‐role expectations associated with pain. Although there is evidence that men and women report using different pain coping strategies, we do not know the extent to which gender‐specific expectations are associated with pain‐related coping. The current study sought to examine this in more detail by administering a standard pain coping measures on three separate occasions, but with different instructions. Hundred and twenty two participants (57 male, 65 female) were asked to complete the coping measure as themselves, then again as they would expect the typical man and the typical woman to complete it. Results indicated that there were no significant differences between men and women in their own self‐reported usage of pain coping strategies. However, there was general evidence to suggest that there are differences in stereotypical views of how men and women are thought to cope with pain. Furthermore, sex differences were also found in how participants viewed their own coping behaviours in comparison to that of the typical man and typical woman. These results confirm that alongside pain, men and women hold different gender‐specific expectations with respect to certain pain coping strategies. Future research is required to examine whether these different coping expectations influence an individuals own choice of strategy, and whether this in turn affects actual pain experiences.
Isolation of human mesenchymal stem cells from third‐trimester amniotic fluid
Authors: You Qi , Cai Liying , Zheng Jianhua , Tong Xiaojing , Zhang Dan , Zhang Yuanlong
Published: August 2008

Objective

To determine whether mesenchymal stem cells (MSCs) can be isolated in third‐trimester amniotic fluid (AF) and their differentiation induced.

Method

Sufficient numbers of MSCs were isolated from the AF of 15 healthy women undergoing cesarean delivery in the third trimester to be cultured and induced to differentiate into osteocytes.

Results

Reverse‐transcriptase polymerase chain reaction showed the MSCs to express the pluripotency marker gene OCT4, and flow cytometry showed these cells to be positive for CD29, CD73, CD90, and CD105 and negative for CD31, CD45, and CD61. The MSCs were also determined to be nontumorigenic.

Conclusion

Multipotent MSCs can be obtained from AF in the third trimester, which may be less dangerous than the second trimester to women and their fetuses.
The need for integrating family planning and postabortion care in China
Authors: Cheng Yimin , Xu Xiao , Xu Juncai , Wuillaume Françoise , Zhu Jinliang , Gibson Diana , Temmerman Marleen
Published: August 2008

Objective

To assess the need for integrating postabortion care with family planning services in China.

Method

We collected data from a clinic‐based study of 24 abortion clinics in 3 large cities in China.

Results

There was a total of 287 (10.3%) high‐risk abortions among the 2780 respondents, 974 (35%) of whom had had repeated abortions and 48.4% had had 2 abortions within 1 year; 63.7% of the current pregnancies resulted from not using contraceptives; 28.8% and 19.8% of these new pregnancies, respectively, were due to the failure of the rhythm or the withdrawal method; only 9.7% of the respondents consistently used condoms; and only 9.1% could identify the correct time of their first ovulation following an abortion.

Conclusion

Contraceptive neglect and the high rates of repeated and high‐risk abortions call for the integration of postabortion care with family planning services in China.
A criterion‐based obstetric morbidity audit in southern Thailand
Authors: Liabsuetrakul Tippawan , Promvijit Thadpong , Pattanapisalsak Chaiwat , Silalai Sorawasa , Ampawa Theeradet
Published: August 2008

Objective

To evaluate the incidences of severe pre‐eclampsia/eclampsia, obstructed labor, and postpartum hemorrhage in the 5 southernmost provinces of Thailand, and the quality of care for these conditions, using a modified version of a criterion‐based clinical audit.

Methods

We reviewed the medical records of the 3669 women admitted in the obstetric wards of 7 referral hospitals from January through March 2005.

Results

Of 515 severely morbid conditions recorded for 486 women (13.2%), there were 113 cases of pre‐eclampsia, 320 of obstructed labor, and 82 of postpartum hemorrhage. Documentation for the diagnosis of obstructed labor was often incomplete. Condition severity and standard of care varied among hospitals. The most common indicators of substandard care were a lack of record of respiratory rate and tendon reflex for women with severe pre‐eclampsia/eclampsia (35%); of antibiotic prophylaxis for those with obstructed labor (28%); and of record of urine output for those with postpartum hemorrhage (32%).

Conclusions

Incomplete diagnosis documentation and evidence of substandard care were common, which warrants auditing for such problems and providing feedback to physicians.
Effectiveness and safety of loop electrosurgical excision procedure in a low‐resource setting
Authors: Rema Prabhakaran , Suchetha Sambasivan , Thara Somanathan , Fayette Jean Marie , Wesley Ramani , Sankaranarayanan Rengaswamy
Published: August 2008

Objective

To evaluate the effectiveness and safety of the loop electrosurgical excision procedure (LEEP) to treat cervical intraepithelial neoplasia (CIN) in a low‐resource setting.

Methods

Women participating in a cervical screening study in India with histologically confirmed CIN unsuitable for cryotherapy were advised to undergo LEEP. One year after treatment the cervix was visually inspected with acetic acid, followed by colposcopy and biopsy taken from abnormal areas. Cure was defined as no clinical or histologic evidence of CIN. Factors influencing cure rates were evaluated by tests.

Results

Of the 311 women who underwent LEEP, 283 reported for 1‐year follow‐up and 248 (87.6%) were disease free. Cure rates were 93.0% for CIN 1, 85.5% for CIN 2, and 72.7% for CIN 3. Minor adverse effects were observed in 34 women and complications were seen in 5 women.

Conclusion

LEEP was associated with minimal complications and acceptable cure rates in a low‐resource setting, although women with larger lesions had lower cure rates.
The Colposcopic Examination
Authors: Frank Jennifer E.
Published: August 2008

Colposcopy is used to evaluate women with genital tract abnormalities and abnormal cervical cytology. It is an office‐based procedure during which the cervix is examined under illumination and magnification before and after application of dilute acetic acid. Colposcopy may include a biopsy of lesions with characteristics of malignancy and premalignancy, such as acetowhite changes, abnormal vascular patterns, and failure to uptake iodine stain. Endocervical sampling may accompany colposcopy, particularly in the evaluation of nonpregnant women with cytology results of atypical glandular cells and adenocarcinoma in situ. Satisfactory colposcopy requires visualization of the entire squamocolumnar junction and margins of any visible lesions. While most midwives do not perform colposcopy, they will provide the pre‐ and postprocedure education, counseling, and evaluation of patients undergoing the procedure. This paper reviews essential information and gives special consideration to colposcopic examination in adolescent women, pregnant women, and postmenopausal women.
Midwifery Data Collection: Options and Opportunities
Authors: Walker Deborah S. , Visger Joan M. , Levi Amy
Published: August 2008

Most midwives are aware of the need to collect clinical practice data and of its usefulness in supporting the care they provide, which contributes to healthy outcomes for mothers and babies. For the individual midwife, there is more than one easily accessible, standardized data collection instrument from which to choose. However, despite these choices, in an American College of Nurse‐Midwives (ACNM) Division of Research (DOR) survey on midwifery clinical data collection (N = 263), the majority of member respondents (n = 135; 51%) reported using a self‐designed data collection tool, and more than one‐third did not know of the ACNM Nurse‐Midwifery Clinical Data Sets (NMCDS). On a larger scale, the midwifery profession is also in need of an organized and consistent approach to data collection for the purpose of capturing midwifery practice and outcomes in order to provide data to support legislation, practice, and policy changes. However, the profession currently lacks a single common midwifery practice database. In order to facilitate data aggregation that captures a larger view of midwifery practice at the local, regional, and national levels, it is imperative that all midwives collect relevant data that are uniform and standardized, and that the midwifery professional organizations move forward with the development of a common electronic database. This article describes currently available data collection tools as well as their best uses, applications to practice, and future directions.
Women and Heart Disease: Missed Opportunities
Authors: Banks Angela D.
Published: August 2008

One woman dies of cardiovascular disease (CVD) every minute in the United States. CVD is the primary cause of mortality in US women, substantially affecting the lives of African American women compared to other ethnic groups. In a national survey conducted by the American Heart Association, 87% of women surveyed failed to cite heart disease as a major threat to their health. These misperceptions may lead women to underestimate their risk for CVD, resulting in a delay in seeking medical care, thus increasing their morbidity and mortality rates. Professional association guidelines and Internet resources for women and their health care providers are available to address the risk factors of smoking, diabetes mellitus, obesity, hypertension, hyperlipidemia, and physical inactivity. Unless women are informed and educated about these risk factors, they are unable to modify their lifestyles, be proactive in their health care, or reduce their cardiovascular risks.
Vitamin D and Mood Disorders Among Women: An Integrative Review
Authors: Murphy Pamela K. , Wagner Carol L.
Published: August 2008

This integrative review evaluates research studies that investigated the association between vitamin D and mood disorders affecting women to determine whether further research comparing these variables is warranted. A literature search using CINAHL, PsycINFO, MEDLINE, and PubMed databases was conducted to locate peer‐reviewed mood disorder research studies that measured serum 25‐hydroxyvitamin D (25[OH]D) levels. Four of six studies reviewed imparted significant results, with all four showing an association between low 25(OH)D levels and higher incidences of four mood disorders: premenstrual syndrome, seasonal affective disorder, non‐specified mood disorder, and major depressive disorder. This review indicates a possible biochemical mechanism occurring between vitamin D and mood disorders affecting women, warranting further studies of these variables using rigorous methodologies.
The Confidence to Practice Midwifery: Preceptor Influence on Student Self‐Efficacy
Authors: Jordan Robin , Farley Cindy L.
Published: August 2008

The imperative for midwifery educators is to transmit to their students midwifery's unique body of knowledge and hallmarks of care that guide midwifery practice. Concerns have been raised about the ability to maintain the unique aspects of midwifery practice in a culture where routine use of intervention prevails. A theory–practice gap may lead to fewer student midwives exposed to the perspective and practices of midwifery during their clinical education. Preceptor role modeling is important to developing student confidence, conceptualized as self‐efficacy, to persist in the practice of midwifery hallmark behaviors, particularly under conditions that undermine these practices. This study examined student perceptions of preceptor behaviors of two midwifery hallmarks of practice: therapeutic presence and non‐intervention in the absence of complication and student self‐efficacy for performing these behaviors. Recent graduates of education programs accredited by the American College of Nurse‐Midwives Division of Accreditation completed researcher‐developed tools regarding perceptions of preceptor behaviors of therapeutic presence and non‐intervention and their outcome expectancy and self‐efficacy for the same behaviors. The results indicate that preceptor behaviors influence student confidence to perform hallmark behaviors. Student belief in the value of the hallmark to benefit women is the biggest predictor of self‐efficacy for hallmark behaviors. Clinical and educational implications and directions for future research are discussed.
Caste and Maternal Health Care Service Use Among Rural Hindu Women in Maitha, Uttar Pradesh, India
Authors: Saroha Ekta , Altarac Maja , Sibley Lynn M.
Published: August 2008

The objective of this study was to examine the association between caste and maternal health care service use among rural Hindu women in India. We analyzed data from the Morbidity and Performance Assessment, a population‐based cross‐sectional study, for 482 Hindu women who were pregnant during January 1998 to January 1999 in Maitha, Uttar Pradesh, India. Maternal health care service use among both upper and lower caste women was very low. Upper caste women were almost three times more likely to use antenatal care (odds ratio [OR] = 2.72; 95% confidence interval [CI], 1.40–5.30), tetanus toxoid (OR = 2.50; 95% CI, 1.48–4.21), and contraceptives (OR = 2.66; 95% CI, 1.28–5.54) and almost five times (OR = 4.77; 95% CI, 1.81–12.54) more likely to have a trained birth attendant compared to the lower caste women. Caste was a significant determinant of tetanus toxoid use and trained birth attendant even after adjusting for sociodemographic factors. Besides caste, maternal literacy was the one sociodemographic factor that was significantly associated with the use of all maternal health care services. Information dissemination and awareness generation can improve the use of subsidized maternal health care services among women of all caste groups.
CEU; Professional Right of Conscience
Authors: Beal Margaret W. , Cappiello Joyce
Published: August 2008

In recent years there have been numerous media reports of professionals attempting to expand the right of conscience and deny health care services requested by consumers. While the media has focused the most attention on pharmacists' right to refuse access to contraception, this trend is an expansion of the right originally established to protect professionals from being required to perform abortions or to provide direct assistance with abortions. State legislatures have addressed this issue, in some cases by overtly protecting consumers' rights and in other cases by broadening professional right of conscience. In this article, the literature on provider right of conscience is reviewed, and approaches advised by professional organizations are discussed.