bluuebunny/crossref_metadata_2025 huggingface dataset:
Printed CP slot antenna design for GPS/WiMAX applications
Authors: Tseng Ching‐Fang , Yang Pai‐Chuan , Lai Chun‐Hung , Lyu Yuan‐Ping , Liu Yu‐Lun
Published: January 2011

In this article, a design of planar circularly polarized slot antenna is presented. The proposed antenna has a simple structure consisting of a modified circle‐like slot ground plane, T‐shaped structure act as a tuning stub of the antenna, placed at the opposite side of the feed. The parametric analysis of the antenna is done by the available electromagnetic solver HFSS. The proposed antenna is developed, and its measured characteristics are in good agreement with the simulated results. From experimental results, the antenna can generate two bands centered at about 1.59 and 3.78 GHz to cover the global position system and the 3.5‐GHz WiMAX band. Good return loss and radiation pattern characteristics are obtained over the two operation bands. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:488–491, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25780
A design methodology for the 60 GHz CMOS power amplifier using on‐chip transformers
Authors: Kim Ki‐Jin , Ahn K.H. , Lim T. H. , Park Hyun Chul , Yu Jong‐Won
Published: January 2011

This letter presents a design methodology for the millimeter wave amplifier using 90‐nm Taiwan Semiconductor Manufacture Company (TSMC) CMOS technology. The proposed design scheme with mathematically modeled transmission lines and interstage matching transformers illustrates how to design a millimeter amplifier considered in the maximum power transfer. The single‐ended transformer‐coupled CMOS PA is implemented to verify the design methodology. The design consists of neutralized common source (CS) amplifiers, matching transmission lines, and 3D modeled transformers. The designed circuit shows 16.2‐dB gain and 9‐dBm saturation power over 60‐GHz channel. The measured results are well matched with the proposed modeling results. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:506–509, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25782
A broadband inverted Doherty power amplifier for IEEE 802.11b/g WLAN applications
Authors: Jin Shilei , Zhou Jianyi , Zhang Lei
Published: January 2011

A broadband inverted Doherty power amplifier (IDPA) is proposed in this article. To achieve the tradeoff between efficiency and operation bandwidth, an optimized output matching network and offset lines are used to design the load network of the proposed power amplifier (PA). For experimental verification, a conventional IDPA and a class‐AB biased balanced PA have been implemented. In addition, a 64‐QAM modulated signal with 24‐MHz channel bandwidth are applied as excitation. According to experiment results, the proposed Doherty power amplifier can keep power‐added efficiency (PAE) higher than 31% from 2.4 to 2.5 GHz with 0.5 dB output‐power flatness at 27‐dBm output power. The PAE of the proposed PA is 16.4% and 4.2% higher than the balanced PA and the conventional IDPA respectively. In addition, the linearity of the proposed PA is improved effectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:636–639, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25785
Parallel metal‐plated tuning fork shaped omnidirectional monopole antenna for UWB application
Authors: Mishra S. K. , Gupta R. K. , Mukherjee J.
Published: January 2011

This article proposes a parallel metal‐plated tuning fork‐shaped omnidirectional antenna for UWB application.Printed monopole antennas fabricated on a substrate offer impedance band width, which can cover UWB. However, radiation pattern varies significantly over the bandwidth. The cross polar component increases with frequency and the pattern degrades from the desired omnidirectional characteristics. Omnidirectional radiation bandwidth can be increased significantly by decreasing the substrate thickness and using substrate material of low dielectric constant. In the proposed antenna, omnidirectional radiation bandwidth is further increased by using rectangular strips on both sides of a semi annular ring monopole antenna. The proposed metal‐plated structure using foam dielectric is designed, fabricated, and tested. The measured voltage standing wave ratio (VSWR) is <2 over 3.1–10.6 GHz frequency band. The antenna offers high efficiency, low cross polarization and its radiation patterns indicate its suitability for UWB applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:601–604, 2011; View this article at wileyonlinelibrary.com. DOI 10.1002/mop.25786
Experimental demonstration of an all‐fiber variable optical attenuator based on liquid crystal infiltrated photonic crystal fiber
Authors: Mathews Sunish , Farrell Gerald , Semenova Yuliya
Published: January 2011

The application of a nematic liquid crystal infiltrated solid core photonic crystal fiber as a novel all‐fiber in‐line electronically controlled broadband fiber optic attenuator in the wavelength range from 1500 to 1600 nm is demonstrated.The device based on photonic bandgap transmission is electronically controlled and, due to its compact configuration, can be easily incorporated into an optical network. A low‐insertion loss at zero attenuation state and a high‐extinction ratio of ∼40 dB are obtained between the high and low transmission states of the attenuator. The device works on the application of a varying voltage applied perpendicular to the fiber axis. The attenuation varies linearly with an increase in voltage, with a ∼3.5 V increment required for 1 dB attenuation. The device is shown to have a flat spectral response for all attenuation states in the wavelength range. The device can be used as the core of a highly efficient in‐line electronically controlled variable fiber optic attenuator. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:539–543, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25789
Multiband printed dipole antenna with log‐periodic toothed structure for WLAN/WiMAX applications
Authors: Nouri H. , Nourinia J. , Ghobadi Ch.
Published: January 2011

In this article, a novel printed dipole antenna using log‐periodic toothed structure is presented for simultaneously satisfying wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The operating frequencies of the proposed antenna are 2.4/5.2/5.8 GHz, which covers WLAN system and 2.5/3.5/5.5 GHz for WiMAX system. The desired resonant frequencies are obtained by adjusting the number of log‐periodic teeth. Also by cutting two slots in the both sides of microstrip feedline on the ground plane, much wider impedance bandwidth can be produced. Prototypes of the proposed antenna have been constructed and studied experimentally. The measured results show good agreement with the numerical prediction and good multiband operation. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:536–539, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25790
Controlling polarization of an optical carrier of double sideband‐suppressed carrier modulated lightwave for improving characteristics of a sub‐terahertz continuous wave generated by photomixing
Authors: Kim Sungil , Kang Kwang‐Yong
Published: January 2011

To improve characteristics of a sub‐terahertz (THz) continuous wave (CW) as controlling polarization of an optical carrier for increase of optical carrier suppression levels, an orthogonally polarized extra optical signal with the same wavelength of an optical carrier was added to the double sideband‐suppressed carrier modulated lightwave (DSB‐SC).Compared with the traditional DSB‐SC, the phase noise and output power characteristics of the sub‐THz CW were improved about 3 dB (50%) at 10 KHz offset frequency and about 2 dB (37%) at 0.1 THz center frequency. Consequently, the controlling polarization technique of the optical carrier can be helpful to make the cost‐saving sub‐THz systems without high‐cost optical filters to increase the optical carrier suppression levels. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:626–630, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25795
A novel Minkowski‐island‐based fractal patch for dual‐mode and miniaturization band‐pass filters
Authors: Liu Ji‐Chyun , Chiu Ssu‐Hung , Kuei Ching‐Pin , Zeng Bing‐Hao
Published: January 2011

A miniaturized dual‐mode band‐pass filter (BPF) using Minkowski‐island‐based (MIB) fractal patch resonator is presented in this article. The BPF is mainly formed by a λg/4 square patch resonator, which is a MIB fractal configuration with second order iteration is embedded in the patch. By tuning the perturbation, which resulted from the fractal patch, two resonant modes are excited and a pair of transmission zeros are generated to improve the BPF performance. The proposed filter at center frequency (f0) of 630 MHz has very good measured characteristics including the bandwidth of 552–708 MHz (3‐dB fractional bandwidth of 24.8%), low insertion loss of –1.38 dB and size reduction with 76.4%. The filter performance is characterized to verify the design concept. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:594–597, 2011; View this article at wileyonlinelibrary.com. DOI 10.1002/mop.25796
Integrated azimuthal lithium niobate electro‐optical electromagnetic field sensor with Mach–Zehnder waveguide modulator and micromultiannular antenna
Authors: Lee Ching‐Ting , Huang Wei‐Hsiang
Published: January 2011

A micromultiannular antenna was integrated with Mach–Zehnder modulator in a LiNbO3 electro‐optical electromagnetic field sensor to measure multiple frequency response. The center response frequency of the multiannular antenna of the electromagnetic field sensor was 1.4, 2.8, and 5.2 GHz, respectively. The sensor system exhibited an average linear dynamic range of 66 dB. The minimum detectable electromagnetic field intensity of the sensor was 2.24, 3.98, and 7.07 mV/m at 1.4, 2.8, and 5.2 GHz, respectively. Furthermore, a system combined with three similar electromagnetic field sensors had function of detecting azimuth source without the effect of the rotating angle of sensor probe around its axis. The directional sensitivity pattern of the electro‐optical electromagnetic field sensor system revealed uniform sensitivity. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:565–567, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25798
Accurate large‐signal characterization of LDMOSFET transistor in package
Authors: Tamoum Mohammed , Allam Rachid , Djahli Farid
Published: January 2011

In this article, we present an accurate characterization of the RF LDMOSFET transistors for the extracting of the large‐signal model. They are generally available encapsulated in package. A measurement of the package parameters are made only by removing the semiconductor chip. The transistor is then characterized by conventional method. The same component can be used in the desired function, thereby avoiding the technological dispersions. The LDMOSFET transistor used is a BLF2043F (NXP semiconductors). To validate our method, we implemented a 2.5‐GHz 10‐W power amplifier. The measured and simulated results match very well. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:575–579, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25800
Multilayered patches with tunable phase response for phased arrays at microwave frequencies
Authors: Padilla P. , Padilla J. L. , Fernández J. M , Sierra‐Castañer M.
Published: January 2011

This manuscript offers the design and prototyping of radiating elements with electronically tunable phase response, for reconfigurable patch array antennas. Different options are found in technical literature to obtain feasible reconfigurable array antennas: placing the active circuitry in the transmission lines or directly over the radiating element, obtaining the desired phase shift for each radiating element of the array. In this manuscript, the second option is selected and electronically reconfigurable stacked patches at Ku band (12 GHz) are designed and prototyped. Eventually, prototype measurements are offered. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:510–514, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25804
Isolation enhancement between two closely mounted antennas for indoor repeater systems
Authors: Kim Sung‐Joo , Harackiewicz Frances J. , Park Myun‐Joo , Kim Taekyun , Jung Woojae , Lee Jeongkwan , Lee Byungje
Published: January 2011

The effect of a frequency‐selective surface (FSS) on enhancing the isolation between a donor and a coverage antenna for indoor WCDMA repeater antenna systems is presented.A unit cell of the proposed FSS consists of a half‐wavelength resonator, an FR4 substrate, and a ground plane. Embedding it on the wall of each reflector for a donor and service antenna, the measured isolation enhancement is about 10 dB. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:697–700, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25806
Triple‐band antenna design using the matching circuit for DVB‐H/PCS/WLAN
Authors: Oh Seon Jeong , Park Sang Yong , Park Jong Kweon
Published: January 2011

In this article, we have proposed triple‐band antenna using matching circuit for DVB‐H/PCS/WLAN applications.The antenna consists of a radiating patch, two folded open strips, and matching circuit. The matching circuit has two chip capacitors and one chip inductor. Two folded open strips are used to obtain the resonances at PCS/WLAN bands. The proposed antenna was designed, fabricated, and measured. Good radiation characteristics have been observed over the operating frequency bands. Details of the proposed antenna design and the simulated and measured results are presented and discussed. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:532–536, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25807
Compact ultra‐wideband bandpass filter with multilayered structure
Authors: Kitamura Toshiaki , Takeuchi Haruhiko , Horii Yasushi
Published: January 2011

A compact ultra‐wideband (UWB) bandpass filter using a multilayered structure is proposed.The proposed filter is composed of a pair of parallel plates, a meander line, and a thin conductor column that connects the parallel plates. The fabricated filter has a small size of 5 × 6 × 1.818 mm3 that amounts to 0.19 λg × 0.22 λg × 0.07 λg, where λg is the guided wavelength at the center frequency of the passband (6.95 GHz). UWB bandpass characteristics from 1.9 to 12.0 GHz with two attenuation poles at 0.4 and 12.8 GHz were achieved. Experimental results are in good agreement with the numerical ones that are obtained from a simulation and an equivalent circuit. Flat group delay characteristics in the wide frequency range are also shown. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:557–559, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25816
Compact ultra‐wideband antennas with single band‐notched characteristic using simple ground stubs
Authors: Weng Y. F. , Cheung S.W. , Yuk T. I.
Published: January 2011

In this article, a compact planar monopole antenna for ultra‐wideband applications with band‐notched characteristic is presented. The antenna with a small size of 30 mm × 39.3 mm operates from 2.57 to over 12 GHz with return loss larger than 10 dB and the radiation patterns similar to that of dipole antennas. A pair of ground stubs locating along the edge of the ground plane is used to create the band‐notch characteristic. The band notch covers the wireless area network band from 5.15 to 5.825 GHz. The center‐notch frequency and notch bandwidth can be adjusted using the dimensions of the ground stubs. Prototype of the proposed antenna is designed, fabricated, and studied. The band‐notched characteristics, return loss, radiation patterns, peak gains, and efficiencies of the antenna are studied using both computer simulation and measurements. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:523–529, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25817
Modeling neuronal current MRI signal with human neuron
Authors: Luo Qingfei , Jiang Xia , Chen Bin , Zhu Yi , Gao Jia‐Hong
Published: January 2011

Up to date, no consensus has been achieved regarding the possibility of detecting neuronal currents by MRI (ncMRI) in human brain. To evaluate the detectability of ncMRI, an effective way is to simulate ncMRI signal with the realistic neuronal geometry and electrophysiological processes. Unfortunately, previous realistic ncMRI models are based on rat and monkey neurons. The species difference in neuronal morphology and physiology would prevent these models from simulating the ncMRI signal accurately in human subjects. The aim of this study is to bridge this gap by establishing a realistic ncMRI model specifically for human cerebral cortex. In this model, the ncMRI signal was simulated using anatomically reconstructed human pyramidal neurons and their biophysical properties. The modeling results showed that the amplitude of ncMRI signal significantly depends on the density of synchronously firing neurons and imaging conditions such as position of imaging voxel, direction of main magnetic field (B0) relative to the cortical surface and echo time. The results indicated that physiologically‐evoked ncMRI signal is too weak to be detected (magnitude/phase change ≤ −1.4 × 10−6/0.02°), but the phase signal induced by spontaneous activity may reach a detectable level (up to 0.2°) in favorable conditions. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Fatigability of spinal reflex transmission in a mouse model (SOD1G93A) of amyotrophic lateral sclerosis
Authors: Schomburg Eike D. , Steffens Heinz , Zschüntzsch Jana , Dibaj Payam , Keller Bernhard U.
Published: January 2011

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive loss of motor neurons. To analyze the progressive motor deficits during the course of this disease, we investigated fatigability and ability of recovery of spinal motor neurons by testing monosynaptic reflex transmission with increasing stimulus frequencies in the lumbar spinal cord of the SOD1G93A mouse model for ALS in a comparison with wild‐type (WT) mice. Monosynaptic reflexes in WT and SOD1G93A mice without behavioral deficits showed no difference with respect to their resistance to increasing stimulus frequencies. During the progression of motor deficits in SOD1G93A mice, the vulnerability of monosynaptic reflexes to higher frequencies increased, the required time for reflex recovery was extended, and recovery was often incomplete. Fatigability and demand for recovery of spinal motor neurons in SOD1G93A mice rose with increasing motor deficits. This supports the assumption that impairment of the energy supply may contribute to the pathogenesis of ALS. Muscle Nerve 43: 230–236, 2011
Subthreshold continuous electrical stimulation facilitates functional recovery of facial nerve after crush injury in rabbit
Authors: Kim Jin , Han Su Jin , Shin Dong Hyun , Lee Won‐sang , Choi Jae Young
Published: January 2011

We sought to determine whether electrical stimulation (ES) with subthreshold, continuous, low‐frequency impulses is a viable clinical method for improving functional recovery after facial nerve crush injury. In 10 rabbits, bilateral crush injuries were made on the facial nerve by compression for 30 s with mosquito forceps, causing complete facial paralysis. Subthreshold continuous direct current ES with 20‐Hz square‐wave pulses was applied to the proximal stump on one side for 4 weeks. Vibrissae movement returned significantly earlier on the ES side, with a less variable recovery time. Electrophysiologically, the stimulated side had a significantly shorter latency, longer duration, and faster conduction velocity. Light and transmission electron microscopy revealed that the electrical stimulation also markedly decreased Wallerian degeneration. The average numbers of fluorescent, double‐labeled nerve cells were significantly different between the ES and non‐ES sides. This study shows that subthreshold, continuous, low‐frequency ES immediately after a crush injury of the facial nerve results in earlier recovery of facial function and shorter overall recovery time. Muscle Nerve 43: 251–258, 2011
Diagnostic utility of stimulated single‐fiber electromyography of the orbicularis oculi muscle in patients with suspected ocular myasthenia
Authors: Mercelis Rudy , Merckaert Virginie
Published: January 2011

Stimulated single‐fiber electromyography (SSFEMG) is a valuable diagnostic tool in cases of myasthenia gravis with limited disease. From 1990 to 2008 SSFEMG in the orbicularis oculi muscle (OO) was performed in a cohort of 456 patients referred with clinical suspicion of myasthenia gravis (MG) and exclusively ocular symptoms. A diagnosis of MG was made on clinical grounds in 103 patients. In this patient cohort, the specificity of SSFEMG for myasthenia was 97%, and the sensitivity was 80%. MG patients with a normal SSFEMG had a benign clinical course. This study confirms a high specificity and sensitivity of SSFEMG when it is performed on patients suspected to have ocular MG. In such patients, a normal SSFEMG of the OO predicts a benign clinical course. Muscle Nerve 43: 168–170, 2011
Motor nerve conduction study in cauda equina with high‐voltage electrical stimulation in multifocal motor neuropathy and amyotrophic lateral sclerosis
Authors: Akaza Miho , Kanouchi Tadashi , Inaba Akira , Numasawa Yoshiyuki , Irioka Takashi , Mizusawa Hidehiro , Yokota Takanori
Published: January 2011

In this study we aim to establish a motor nerve conduction study (NCS) for the cauda equina and examine its usefulness in multifocal motor neuropathy (MMN) and amyotrophic lateral sclerosis (ALS). NCS of the tibial nerve proximal to the knee was performed with an optimized high‐voltage electrical stimulation (HV‐ES) method in 21 normal subjects, 5 with MMN, and 11 with ALS. HV‐ES, but not magnetic stimulation, could supramaximally stimulate the cauda equina. Cauda equina motor conduction time determined by HV‐ES, but not that with F‐waves, correlated well with cauda equina length on magnetic resonance imaging. HV‐ES revealed proximal lesions in 4 MMN patients but in none of the ALS patients. Importantly, 1 patient with “MMN without conduction block (CB)” had a CB in the cauda equina. Cauda equina motor conduction is better evaluated by HV‐ES than with F‐wave study or magnetic stimulation. HV‐ES can help to distinguish MMN and “MMN without CB” from ALS. Muscle Nerve 43: 274–282, 2011
Detection of fibrillations using muscle ultrasound: Diagnostic accuracy and identification of pitfalls
Authors: Alfen Nens Van , Nienhuis Mark , Zwarts Machiel J. , Pillen Sigrid
Published: January 2011

We prospectively investigated the diagnostic accuracy and potential pitfalls of dynamic muscle ultrasound in the detection of fibrillations. The presence of fibrillations on both electromyography (EMG) and ultrasound was evaluated in 102 muscles of 38 patients with suspected fibrillation potentials, based on history and physical examination. Sensitivity and specificity were calculated. False‐positive and false‐negative results are described to identify pitfalls. Ultrasound detected fibrillations with a sensitivity of 45% and a specificity of 66%. Specificity improved to 85% when measurements were evaluated online. Proximal muscles showed higher sensitivities (63%) than distal muscles (33%). Ultrasound currently has a poor sensitivity and moderate specificity for detecting fibrillations. Several pitfalls were identified that, when avoided, could help improve diagnostic accuracy. Ensuring a distal limb temperature of at least 34°C and identifying external movement artifacts as well as voluntary contractions can improve efficacy and open the way for diagnostic application of this technique. Muscle Nerve 43: 178–182, 2011
The choice of experimental models in cancer research: The key to ultimate success or failure?
Authors: Denekamp Juliana
Published: January 2011

The technologies available for assessing the size and physiological status of malignant tumours are becoming more and more sophisticated. Some of these detect phenotypic biochemical alterations resulting from the genetic changes associated with malignant transformation. Many, however, monitor the abnormal relationship between the tumour mass and the host, detecting pathophysiological changes which result from the host/tumour interaction. The most important of these involve the microregional heterogeneities of nutrients resulting from diffusion patterns around abnormal, newly‐formed vascular networks, or inflammatory or immune responses of the host to the tumour. In order to validate new technologies for introduction to clinical medicine they are usually extensively tested in experimental models for cancer. The relevance of these models (whether in vitro cell cultures or experimental tumours) must be considered carefully at the outset, with the factors that influence the parameter being measured, e.g., oxygen or energy status, being given special attention. The genetic similarity of tumour and host, the site of tumour growth, the size of the tumour, the burden it imposes and the immunocompetence of the host are all important features of the experimental model. Inappropriate models may give totally misleading information which cannot be extrapolated to human cancers.
Practicalities of localization in animal and human tumours
Authors: Leach M. O.
Published: January 2011

Factors affecting the selection and application of localization methods for measuring tumours by NMR spectroscopy are considered, with particular regard to the S/N ratio and to contaminating signal from outside the volume of interest. Methods of assessing the performance of localization techniques are considered, and their importance for quantitative measurements and comparative studies is discussed.
Bioluminescence and fluoroscopic imaging of tissue pH and metabolites in experimental brain tumors of cat
Authors: Hossmann K.‐A. , Linn F. , Okada Y.
Published: January 2011

The regional distribution of ATP, glucose, lactate and tissue pH was studied by bioluminescence and fluoroscopic imaging of intact cryostat sections of implantation tumors of cat. In tumors, marked heterogeneity of metabolites and pH was present: in solid parts ATP was similar to normal brain but glucose tended to decrease with an increase in lactate and pH to above normal; in necrobiotic regions ATP declined and pH became acidic. In peritumoral edema, ATP was consistently decreased whereas glucose, lactate and pH increased above normal. Correlation of ATP with water revealed an inverse relationship both in tumor and peritumoral edema but correlation of water with pH was direct in edema and inverse in tumors. The associations and dissociations of lactate, ATP and pH are interpreted in terms of aerobic and anaerobic glycolysis, as well as in respect to the extracellular localization of tumor edema. The findings are of relevance for the interpretation of volume selective NMR spectra and stress the importance of precise volume localization for differentiating between edema and tumor‐mediated metabolic alterations.
Positron emission tomography for tumour assessment
Authors: Jones T. , Tilsley D. W. O. , Wilson C. B. J. H. , Lammertsma A. A. , Brown G. , Brady F. , Price P. M.
Published: January 2011

As positron emission tomography (PET) is outside of the main theme of this conference, it is necessary to outline what it offers as a method for assessing tissue function in vivo. This is followed by illustrations of how PET has and is being used to study the physiology and biochemistry of tumours and pharmacokinetics and pharmacology of anticancer agents. Strategies are offered as to how PET may be used for the development of new chemotherapeutic agents.
Non‐invasive MRS in new anticancer drug development
Authors: Workman Paul , Maxwell Ross J. , Griffiths John R.
Published: January 2011

In the rational development of anticancer drugs it is important to employ all the available pharmacological information. Early clinical trials provide an opportunity for hypothesis testing. MRS techniques have the potential to provide valuable data on the preclinical and clinical pharmacokinetics and pharmacodynamics of drugs non‐invasively. Here we illustrate advantages and pitfalls of MRS using studies of two fluorine‐containing cancer drugs: a β,β‐difluoro analogue of the alkylating agent chlorambucil and a fluorinated derivative of the nitroimidazole misonidazole, Ro 07–0741. Limitations include signal quenching via protein binding and inadequate sensitivity for more potent drugs like β,β‐difluorochlorambucil; but fluoromisonidazole was shown to accumulate in tumours and shows promise as a chemical probe for tumour hypoxia, detectable by 19F MRS.
Parental views on tissue banking in pediatric oncology patients
Authors: McMurter Britney , Parker Louise , Fraser Robert B. , Magee J. Fergall , Kozancyzn Christa , Fernandez Conrad V.
Published: January 2011

Purpose

Research using banked tissue is key to advancing risk‐stratification and treatment of children with cancer. Knowledge of parental attitudes to ethical issues arising in tissue banking is very limited but essential in obtaining respectful consent.

Methods

One hundred parents of consecutively diagnosed children with cancer were offered a validated 34‐item questionnaire.

Results

Respondents (n = 54) included 10 of 16 parents of deceased children. The majority (89%; n = 48) would agree to have tissue sent anywhere in the world but prefer pediatric aims (69%). Most (98%; n = 53) would permit genetic research, if it might improve the child's health, and 76% (n = 41) would permit it, even if no impact was anticipated. A minority (41%) would not allow painful, strictly research procedures, while 15% would regardless of the child's dissent. Just over half (54%; n = 29) wish to renew consent if stored tissue is used for another purpose. Most (98%) believe their child should confirm consent by the age of majority, but only 71% believe the mature child should be able to withdraw consent. A minority (n = 40; 74%) claim few or no rights to research profits; 83% believe these should be used to fund childhood cancer research.

Conclusions

Parents are very supportive of tissue research, including genetic research. A majority of parents would prefer restricting research to pediatric conditions, and to be informed of results, even if of uncertain significance. These findings may assist Institutional Review Boards in assessing parentally perceived risks of research, and researchers in providing consent elements that support parents and adolescents in making fully informed choices. Pediatr Blood Cancer 2011; 57: 1217–1221. © 2011 Wiley Periodicals, Inc.
Different outcome in older children with acute lymphoblastic leukemia with different treatment protocols in the Netherlands
Authors: Boudestein Kris , Kamps Willem A. , Veerman Anjo J.P. , Pieters Rob
Published: January 2011

Background

From 1991 until 2004 children with acute lymphoblastic leukemia (ALL) in the Netherlands were treated according to protocols ALL‐8 and ALL‐9 which were based on different principles. An earlier study showed that the outcome of adolescents highly differed on these protocols.

Procedure

In this retrospective study, we analyzed whether the outcome of older children 10–15 years of age at diagnosis differed between the Berlin‐Frankfurt‐Münster (BFM)‐based ALL‐8 regimen and the ALL‐9 regimen. Two hundred fifty‐four older children who were treated according to protocol ALL‐8 (n = 82) or ALL‐9 (n = 172) were included in the analysis.

Results

A higher 5‐year event‐free survival (EFS) rate was found for patients treated according to ALL‐8 compared to ALL‐9 (79 ± 5% vs. 65 ± 4%, P = 0.02). Patient characteristics did not differ except for a slightly higher age in ALL‐8. Therefore, additional analyses were done including only patients who were 12–15 years of age. In this age group there was also a difference in the 5‐year EFS (82 ± 5% vs. 61 ± 5%, P = 0.00) as well as in the 5‐year overall survival rate; 89 ± 4% compared to 68 ± 5%, respectively (P = 0.01). Major difference between protocols was the use of a consolidation and reinduction/intensification course and higher cumulative doses of asparaginase, methotrexate, and anthracyclines in ALL‐8.

Conclusions

Children 10–15 years of age have been undertreated with the ALL‐9 regimen and benefit by intensive treatment components as used in ALL‐8. We recommend using BFM‐based protocols for these older children with ALL. Pediatr Blood Cancer 2012; 58: 17–22. © 2011 Wiley Periodicals, Inc.
Late effects in childhood cancer survivors: A review with a framing effect bias?
Authors: Fryer Christopher
Published: January 2011

Most publications report the adverse (negative) health issues in childhood cancer survivors. Presenting information to the newly diagnosed patient in a positive manner is advocated, while noting that recurrence is the most likely adverse event. Re‐analysis of population‐based studies on life‐threatening toxicities from Nordic, Dutch, United Kingdom, French, Italian, and N. American publications shows that 5‐year survivors have a near normal life expectancy, 75% have no severe or life‐threatening treatment related toxicity and 87% remain free of a second malignancy. Children who received radiation or anthracycline >250–300 mg/m2 are at greatest risk for treatment related life‐threatening toxicities. Pediatr Blood Cancer 2011; 57: 1100–1103. © 2011 Wiley Periodicals, Inc.
PERSOC: A Unified Framework for Understanding the Dynamic Interplay of Personality and Social Relationships
Authors: Back Mitja D. , Baumert Anna , Denissen Jaap J.A. , Hartung Freda–Marie , Penke Lars , Schmukle Stefan C. , Schönbrodt Felix D. , Schröder–Abé Michela , Vollmann Manja , Wagner Jenny , Wrzus Cornelia
Published: January 2011

The interplay of personality and social relationships is as fascinating as it is complex and it pertains to a wide array of largely separate research domains. Here, we present an integrative and unified framework for analysing the complex dynamics of personality and social relationships (PERSOC). Basic principles and general processes on the individual and dyadic level are outlined to show how personality and social relationships influence each other and develop over time. PERSOC stresses the importance of social behaviours and interpersonal perceptions as mediating processes organized in social interaction units. The framework can be applied to diverse social relationships such as first encounters, short–term acquaintances, friendships, relationships between working group members, educational or therapeutic settings, romantic relationships and family relationships. It has important consequences for how we conceptualize, understand, and investigate personality and social relationships. Copyright © 2011 John Wiley & Sons, Ltd.
Characterization of AlGaInN layers using X‐ray diffraction and fluorescence
Authors: Groh Lars , Hums Christoph , Bläsing Jürgen , Krost Alois , Dadgar Armin
Published: January 2011

Quantum well structures for nitride‐based LEDs are mainly grown in c‐direction, whereby the quantum confined Stark‐effect (QCSE) reduces the overlap of the electron and hole wave function and with it the internal quantum efficiency. The reason for that is the difference in polarization of the quantum well and barrier materials. In order to balance these polarizations, quaternary (AlGaIn)N layers for the later use as barrier material have been grown. In addition to the bandgap energy, another parameter, the polarization, can be controlled in this way. As a standard characterization method X‐ray diffraction measurements have been performed. Due to the impossibility of fully determining the composition using this method, total reflection X‐ray‐fluorescence (TXRF) has been used to get the missing information.
Scanning electron microscopic changes in granulosa cells during follicular atresia in Caprine ovary
Authors: Bhardwaj J. K. , Sharma R. K.
Published: January 2011

During this study, topographic changes in healthy and atretic granulosa cells have been investigated during follicular atresia in goat ovary. Under scanning electron microscopy atresia was marked by asymmetrical shrinkage and vacuolization of cytoplasm. The specific topographical alterations observed in atretic cells were loss of micro extensions, disruption of cell–cell interaction, and smooth‐textured membrane with a number of uneven depressions and ruffles. Some portions of the cell membrane were marked by extensive shrinkage due to condensation of cytosol. Irregular membrane at occasions was studded with blunt microextensions. The findings of present investigation will help in understanding the cellular changes in granulosa cells during follicular atresia and will find applications in screening of follicles for in vitro culture, in vitro fertilization and Embryo transfer technology. SCANNING 33: 21–24, 2011. © 2011 Wiley Periodicals, Inc.
Online evaluation of fetal second‐trimester four‐chamber view images: a comparison of six evaluation methods
Authors: Jaudi S. , Tezenas Du Montcel S. , Fries N. , Nizard J. , Halley Desfontaines V. , Dommergues M.
Published: January 2011

Objective

To compare six online evaluation methods for auditing routine second‐trimester four‐chamber view still images.

Methods

We evaluated three different scoring grids (subjective, five‐item score and seven‐item score), which were applied with or without access to online help, resulting in a total of six evaluation methods. For the subjective scoring grid, images were rated as excellent, good, fair, poor or very poor. For the five‐item score, 1 point was allocated for visualization (vs non‐visualization or non‐evaluable) of each of: heart crux, atria, ventricles, apex and aorta, yielding a score of 0–5. For the seven‐item score, 1 point was allocated for clear (vs unclear) visualization of each of: moderator band at the apex, interventricular septum, atrioventricular valves, non‐linear insertion of atrioventricular valves (normal offset), septum primum, aorta and pulmonary vein. Each evaluation method was used via the Internet by three randomly selected reviewers, who evaluated the same set of 80 images. Reviewers were experienced in fetal ultrasound, but were not involved in the design of the study. Interrater agreement was the main outcome.

Results

The five‐item scoring grid with online help achieved the best interrater agreement (interrater intraclass correlation coefficient = 0.7).

Conclusions

Evaluation of the second‐trimester sonographic four‐chamber view is apparently best achieved with a simple five‐item scoring grid. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Social and demographic correlates of contraceptive adoption in a rural area of East Pakistan
Authors: Stoeckel John
Published: January 2011

Se ha sometido a prueba las hipótesis que tratan de la relación entre variables sociales y demogrdficás y la adopción de la práctica del planeamiento familiar, como un proceso, para personas que iniciaron su adopción durante los años 1962 a 1966, en una zona rural de Pakistan Este. Los hallazgos indican que la adopción de largo plazo (13 meses o más), está asociada con la participación cooperativa, Hinduismo, el grupo de edad de treinta años o mas, edad al momento del matrimonio de quince años o más, y paridad de seis o más niños. La ocupación, educación, y la tenencia de tierra no mostraron una relación constante con la adopción. Se discute posibles razones de estos resultados.
That earlier plague
Authors: Russell Josiah C.
Published: January 2011

La plaga que apareció alrededor del ano 542 de nuestra era, continuó como una serie de epidemias durante la séptima centuria y siguió un modelo muy parecido al de la Peste Negra del siglo XIV. Previamente el emperador Bizantino Justiniano (527–565) habia recapturado el norte de Africa anteriormente controlado por los Vandalos y la mayor parte de Italia de manos de los Ostrogodos.

La perspectiva de restablecimiento del completo Imperio Romano parecía buena desde que las condiciones en el Este eran excelentes y la mayor parte del Oeste habría recibido con alegría sus ejércitos. La plaga interrumpió y probablemente hi o imposible el cumplimiento de ese programa. Casi tan destructiva como la posterior (Peste Negra) esta plaga redujo la población entre 40 y 50 por ciento hacia el fin del siglo. Esto simplificó la cultura al reducir el tamaño de las ciudades. La más alta mortalidad de las pequeñas familias perjudicó al clero y a los grupos más educados. Las más ligeras perdidas en las areas secas tendieron a alterar el balance entre semi-nomades y areas de colonizacón. La sociedad fue cambiada radicalmente y quedo emocionalmente desequilibrada.

Bajo el peso de la creciente depresión y perdida de la población, el Imperio Bizantino tuvo que reducir el tamaño de sus ejércitos. No solo fué la ofensiva en el Oeste abandonada despues del 565, sino que las defensas al Sur fueron tan debilitadas que el Islam, en la siguiente centuria tomaría facilmente Egipto y Siria. Las condiciones mas simples inducidas por la plaga of recieron una oportunidad ideal para el desarrollo y la difusión del Islam especialmente en las areas nomanes y seminomades. En el Oeste la amenaza de expansión de los francos se debilitó y creció el localismo. El patron de dominación de Griegos, Arabes, y Germanos iba a persistar por siglos.
The effects of differing trends in fertility and of educational advance on the growth, quality, and turnover of the labor force
Authors: Jones Gavin , Gingrich Paul
Published: January 2011

Relativamente, pocos intentas se han hecho para investigar el efecta de diferentes tendencias de la fecundidad sobre el subsiguiente crecimiento, la composición por edades y el cambio en la fuerza de trabajo en los paises subdesarrollados. Aún menor atención se le ha prestado a la interrelación entre tendencias alternativas de fecundidad y trayectorias alternativas de avance educacional, en la determinación de la “calidad” y cambio de la fuerza de trabajo en años subsiguientes.

El presente trabajo es un modesto intento de rectificar esta deficiencia. Una población con una estructura por edades, tasas vitales, y tasas de registro escolar, representativas de muchos paises del Asia del Sur, Medio Este, y Africa, fué proyectada por sesenta años, de acuerdo a los siguientes grupos de condiciones:(a) fecundidad constante-tasas de registro educacional constantes;(b) fecundidad constante-tasas mejoradas de registro educacional;(c) fecundidad descendente-tasas de registro educacional constantes;(d) fecundidad descendente-tasas mejoradas de registro educacional.

El crecimiento, la estructura por edades, y las tasas de reemplazo y de logro educacional de la fuerza del trabajo, resultantes de las varias proyecciones, fueron sometidas a examen. Los resultados indican que, en contra de una argumentación común, el mantenimiento de una fecundidad elevada no dá como resultado un reemplazo más rápido de la fuerza de trabajo inicial, pobremente educada, por trabajadores mejor educados. La fuerza de trabajo original es reemplazada en forma algo más rápida cuando la fecundidad permanece alta y cuando las tasas de asistencia a las escuelas no se elevan. Pero controlando las tasas de asistencia a las escuelas, las tendencias en el loqro educacional de la fuerza del trabajo, durante un período de sesenta años, permanecen casi idénticas en las proyecciones constante y descendente de la fecundidad.
Concerning an index of mortality
Authors: Hillery George A. , Saunders John V. D.
Published: January 2011

La posibilidad de construir un índicede mortalidad a partir de datos de edad, suqiere la hipótesis de que la mortalidad está directamente relacionada con la baja de fertilidad e inversamente relacionada al porcentaje de personas de edad avanzada. Las medidas de mortalidad seleccionadas fueron expectativa de vida al nacer, al año, y a los cinco años. Una muestra de 21 naciones fue seleccionada principalmente en términos de la calidad de sus tobias de vida y datos de edad. La formula que permite la mas alta correlacion (r = -0.861) fue obtenida para la expectación de vida al año y un índice de mortalidad basado en las siguientes categorias (los numeros se refieren a años de edad en la poblacion femenina solamente). (0 — 14) (poblacion total)/(15–74) (75 y mas). Tests con otras poblaciones dieron incluso más altas correlaciones. Las correlaciones para la poblacion masculina son ligeramente más bajas en todos los casos. En elartículo incluimos inetrucciones y suqestiones para la computación, El indice resulia mas apropiado para poblaciones que no sean demasiado influenciadas por migraciones y con sistemas incompletos de registro.
The role of sampling in population censuses: Its effect on timeliness and accuracy
Authors: Waksberg Joseph
Published: January 2011

Resumen A pesar de que la mayoría de los paisee del mundo han, a la fecha, comprendido la importancia de tener censos periódicos de población y han tomado las disposiciones para realizarlos regularmente, por una variedad de razones muchos paises encuentran dificil producir los resultados de esos censos en un periodo razonable de tiempo. Por ejempolo de los 17 paises de Latinoamerica para los cuales hay datos disponibles de recientes censos de poblacion al comienzo del ano 1967, por lo menos una serie de resultados finales habian sido publicados en 12 casos. Para esos 12 el tiempo promedio requerido para las mas tempranas publicaciones fue superior a los tres años; para algunos de esos paises parece probable que el plazo haya sido de cinco años. Este artículo discute algunos aspectos de la necesidad de ahorrar tiempo en la publicación de los resultados, investiga los efectos de largos retrazos en nuestra comprensión de los cambios que estan ocurriendo. Describe métodos de acelerar la preparación de informes, y sugiere un proqranui para expandir el empleo de muestras en los censos de los paises en desarrollo.

Dos métodos pueden ser desarrollados mediante el uso de muestras para acelerar el tratamiento de los resultados censales. El primer método consiete en usar pequeñas muestras para un programa de informes preliminares, los cuales son seguidos luegos por informes finales basadoe en el censo total. En el segundo metodo se abandona la noción de trabajar con el cien por ciento de los datos, con exepción de un mínimo de información y recoqer la mayor parte de las estadísticas por medio de muestras es la principal técnica usada.

Un programa exitoso en la producción de informes preliminares por medio de muestras fue llevado a cabo para 13 de los 17 paises latinoamericanos mencionados. En esos paises la ganancia media en tiempo como resultado de ese programa fue de alrededor de dos años. Ademas en todos los casos examinados los datos preliminares fueron muy parecidos a los resultados finales. Algunos paises, generalmente los mas industrializados, han extendido el uso de muestreo a la recolección de datos básicos para ahorrar tiempo y reducir costos. En general esto puedo ser hecho con solo un efecto menor en la exactitud. De hecho, si algunos de los ahorros en tiempo y recursos que surgen del uso de muestras son utilizados para mejorar los procedimientos, para poner más énfasis en supervisión y control del trabajo de campo, la reliabilidad puede ser incluso mayor. Además nuestro análisis indica que si se usan datos censoles continuamente durante una década y que si el uso de muestras permite adelantar dos años la publicación, el efecto total del error de muestreo va a ser menor que el causado por el uso durante largo tiempo de estadísticas atrasadas. Nosotros sugerimos un programa para el planeamiento de censos con una considerable expansión del uso de muestras. Un sumario breve de los mayores requerimientos y consideraciones de este programa es incluido en esie artículo.