bluuebunny/crossref_metadata_2025 huggingface dataset:
A TIP OF THE ICEBERG? THE PROBABILITY OF CATCHING CARTELS
Authors: Ormosi Peter L.
Published: April 2013

Reliable estimates of crime detection probabilities could help in designing better sanctions and improve our understanding of the efficiency of law enforcement. For cartels, we only have limited knowledge on the rate at which these illegal practices are discovered. In comparison to previous works, this paper offers a more parsimonious and simple‐to‐use method to estimate time‐dependent cartel discovery rates, while allowing for heterogeneity across firms. It draws on capture–recapture methods that are frequently used in ecology to make inferences on various wildlife population characteristics. An application of this method provides evidence that less than a fifth of cartelising firms are discovered. Copyright © 2013 John Wiley & Sons, Ltd.
Uranium dynamics and developmental sensitivity in rat kidney
Authors: Homma‐Takeda Shino , Kokubo Toshiaki , Terada Yasuko , Suzuki Kyoko , Ueno Shunji , Hayao Tatsuo , Inoue Tatsuya , Kitahara Keisuke , Blyth Benjamin J. , Nishimura Mayumi , Shimada Yoshiya
Published: April 2013

Renal toxicity is the principal health concern after uranium exposure. Children are particularly vulnerable to uranium exposure; with contact with depleted uranium in war zones or groundwater contamination the most likely exposure scenarios. To investigate renal sensitivity to uranium exposure during development, we examined uranium distribution and uranium‐induced apoptosis in the kidneys of neonate (7‐day‐old), prepubertal (25‐day‐old) and adult (70‐day‐old) male Wistar rats. Mean renal uranium concentrations increased with both age‐at‐exposure and exposure level after subcutaneous administration of uranium acetate (UA) (0.1–2 mg kg–1 body weight). Although less of the injected uranium was deposited in the kidneys of the two younger rat groups, the proportion of the peak uranium content remaining in the kidneys after 2 weeks declined with age‐at‐exposure, suggesting reduced clearance in younger animals. In situ high‐energy synchrotron radiation X‐ray fluorescence analysis revealed site‐specific accumulation of uranium in the S3 segment of the proximal tubules, distributed in the inner cortex and outer stripe of the outer medulla. Apoptosis and cell loss in the proximal tubules increased with age‐at‐exposure to 0.5 mg kg–1 UA. Surprisingly, prepubertal rats were uniquely sensitive to uranium‐induced lethality from the higher exposure levels. Observations of increased apoptosis in generating/re‐generating tubules particularly in prepubertal rats could help to explain their high mortality rate. Together, our findings suggest that age‐at‐exposure and exposure level are important parameters for uranium toxicity; uranium tends to persist in developing kidneys after low‐level exposures, although renal toxicity is more pronounced in adults. Copyright © 2013 John Wiley & Sons, Ltd.
Preosteoblasts behavior in contact with single‐walled carbon nanotubes synthesized by radio frequency induction thermal plasma using various catalysts
Authors: Alinejad Yasaman , Faucheux Nathalie , Soucy Gervais
Published: April 2013

The influence of single‐walled carbon nanotubes (SWCNTs) produced by radio frequency (RF) induction thermal plasma with three catalyst mixtures (Ni‐Co‐Y2O3, Ni‐Y2O3 and Ni‐Mo‐Y2O3) was evaluated on the behavior of murine MC3T3‐E1 preosteoblasts. After analyzing SWCNTs properties, mitochondrial enzymatic (MTS) and lactate dehydrogenase (LDH) activities as well as neutral red (NR) uptake were measured to assess the cellular viability. To ascertain that the cytotoxicity was not merely as a result of the mechanical disturbance, either SWCNTs were added on the attached cells or cells were seeded on the SWCNT‐covered plates. Regardless of the catalyst mixtures used for their production, SWCNTs added on the attached cells reduced cell viability drastically in a dose‐dependent manner. However, the viability of cells seeded on SWCNTs even on those produced with Ni‐Co‐Y2O3 was slightly decreased at 24 h and besides cells could proliferate within 48 h. Furthermore, cells were able to organize normal filamentous actin cytoskeleton and no apoptotic cells were detected in the cultures. Thus except mechanical disturbance, thermal plasma grown SWCNTs seem to induce no severe cytotoxicity on MC3T3‐E1 preosteoblasts and therefore are considered promising CNTs to be studied more deeply for future applications in bone tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.
Influence of cadmium on metallothionein expression and products of lipid peroxidation in the organs of hares (Lepus europaeus Pallas)
Authors: Linšak Dijana Tomić , Linšak Željko , Špirić Zdravko , Srebočan Emil , Glad Marin , Cenov Arijana , Jakovac Hrvoje , Milin Čedomila
Published: April 2013

Cadmium occurs naturally in the environment and as an anthropogenic pollutant. Exposure to low concentrations of cadmium is inevitable and may produce toxic effects. Another important aspect of cadmium toxicity is its interaction, often antagonistic, with essential elements such as selenium. The aim of this study was to highlight the risks of long‐term exposure to low cadmium concentrations, using a scientific and chemical approach and hares (Lepus europaeus Pallas) as model organisms in a field study. Two study areas were monitored. Levels of cadmium and selenium were quantified in the organs of hares, the expression of metallothioneins I + II and the products of lipid peroxidation were determined. The median cadmium concentrations (wet weight) in the muscle, liver, kidney and brain of hares from an exposed group ranged from 0.033 to 0.037, 0.763 to 1.054, 3.090 to 16.594 and 0.016 to 0.087µg g−1, respectively; whereas, the median selenium concentrations (wet weight) ranged from 0.100 to 0.108, 0.153 to 0.332, 0.677 to 0.701 and 0.078 to 0.116µg g−1, respectively. Expression of the metallothioneins I + II proteins was observed in tissues. Lipid peroxidation (LPO) levels, measured as malondialdehyde (MDA) equivalents, increased with the cadmium concentration. Further research on long‐term exposure to low concentrations of cadmium in the environment is needed. Copyright © 2013 John Wiley & Sons, Ltd.
Exposure of neonatal rats to the endocrine disrupter Bisphenol A affects ontogenic expression pattern of testicular steroid receptors and their coregulators
Authors: Salian‐Mehta Smita , Doshi Tanvi , Vanage Geeta
Published: April 2013

In light of the adverse reports of Bisphenol A (BPA) on reproduction and considering the pivotal role played by the steroid receptors (SRs) and their coregulators in male reproduction, it was of interest to decipher the influence that BPA may have on their expression pattern during critical ’windows‘ of development. Male rats were injected with 2.4 µg per pup per day of BPA from postnatal days (PND) 1–5 and controls received vehicle. During development, the testicular expression pattern of SRs (AR, ERβ and ERα), coactivators (SRC‐1, SRC‐2 and SRC‐3) and corepressors (NCoR and SMRT) in BPA‐exposed rats were compared. A significant decrease in the expression of SRs was seen in the BPA group. SRC‐1 showed a significant decrease, whereas SRC‐2 and SRC‐3 showed a significant increase in the protein expression whereas corepressor expression remained unaltered in the BPA‐exposed groups. Such impairments in the expression pattern can be a putative mechanism of adversities on fertility as a result of BPA exposure. Copyright © 2013 John Wiley & Sons, Ltd.
PHAISTOS: A framework for Markov chain Monte Carlo simulation and inference of protein structure
Authors: Boomsma Wouter , Frellsen Jes , Harder Tim , Bottaro Sandro , Johansson Kristoffer E. , Tian Pengfei , Stovgaard Kasper , Andreetta Christian , Olsson Simon , Valentin Jan B. , Antonov Lubomir D. , Christensen Anders S. , Borg Mikael , Jensen Jan H. , Lindorff‐Larsen Kresten , Ferkinghoff‐Borg Jesper , Hamelryck Thomas
Published: April 2013

We present a new software framework for Markov chain Monte Carlo sampling for simulation, prediction, and inference of protein structure. The software package contains implementations of recent advances in Monte Carlo methodology, such as efficient local updates and sampling from probabilistic models of local protein structure. These models form a probabilistic alternative to the widely used fragment and rotamer libraries. Combined with an easily extendible software architecture, this makes PHAISTOS well suited for Bayesian inference of protein structure from sequence and/or experimental data. Currently, two force‐fields are available within the framework: PROFASI and OPLS‐AA/L, the latter including the generalized Born surface area solvent model. A flexible command‐line and configuration‐file interface allows users quickly to set up simulations with the desired configuration. PHAISTOS is released under the GNU General Public License v3.0. Source code and documentation are freely available from http://phaistos.sourceforge.net. The software is implemented in C++ and has been tested on Linux and OSX platforms. © 2013 Wiley Periodicals, Inc.
Common vertex matrix: A novel characterization of molecular graphs by counting
Authors: Randić Milan , Novič Marjana , Plavšić Dejan
Published: April 2013

We present a novel matrix representation of graphs based on the count of equal‐distance common vertices to each pair of vertices in a graph. The element (i, j) of this matrix is defined as the number of vertices at the same distance from vertices (i, j). As illustrated on smaller alkanes, these novel matrices are very sensitive to molecular branching and the distribution of vertices in a graph. In particular, we show that ordered row sums of these novel matrices can facilitate solving graph isomorphism for acyclic graphs. This has been illustrated on all undecane isomers C11H24 having the same path counts (total of 25 molecules), on pair of graphs on 18 vertices having the same distance degree sequences (Slater's graphs), as well as two graphs on 21 vertices having identical several topological indices derived from information on distances between vertices. © 2013 Wiley Periodicals, Inc.
Biophysical study of novel oligoelectrolyte‐based nonviral gene delivery systems for mammalian cells
Authors: Ficen Semra Zuhal , Guler Zeliha , Mitina Nataliya , Finiuk Nataliya , Stoika Rostyslav , Zaichenko Alexander , Ceylan Sebnem Ercelen
Published: April 2013

Background

Gene therapy is an important treatment for genetic and acquired diseases. The success of gene therapy is largely dependent on the development of suitable vectors for gene transfer. Vectors are needed to overcome cellular barriers and to achieve efficient DNA delivery with low cytotoxicity. In the present study, we synthesized and characterized a novel comb‐like oligoelectrolyte nanocarrier, BG‐2, as a nonviral gene delivery vector.

Methods

A novel surface‐active oligoelectrolyte of comb‐like structure was synthesized via controlled radical copolymerization using oligoperoxide Cu+2 coordinating complex as a multisite initiator of graft copolymerization. The critical micellar concentration was determined by Nile Red fluorescence. Complex formation of DNA with BG‐2 was determined by YOYO‐1 fluorescence. The physicochemical properties of DNA in complex with BG‐2 have been investigated by electrophoresis, dynamic light scattering and fluorescence spectroscopy. The BG‐2/DNA complex was demonstrated by scanning electron microscopy. Interactions between BG‐2/DNA complex and model membranes were also studied. The sensitivity of the DNA molecule, complexed with BG‐2, against deoxyribonuclease I and serum nucleases was assessed by agarose gel electrophoresis. BG‐2 efficiency in the transfection of HeLa cells was determined by measuring luciferase gene expression using a luminometer and cytotoxicity was also evaluated.

Results

BG‐2 oligoelectrolyte was successful in overcoming cellular barriers as a result of forming stable and small sized complexes with DNA, interacting with model membranes in a desirable manner and protecting DNA from nuclease. The transfection efficiency was quite high and cytotoxicity was low.

Conclusions

BG‐2 appears to be a promising nonviral vector with low cytotoxicity and efficient transfection properties. Copyright © 2013 John Wiley & Sons, Ltd.
The role of enhanced thermal pressure in the earthward motion of the Earth's magnetopause
Authors: Shue J.‐H. , Chao J.‐K.
Published: April 2013

The magnetopause is the thin boundary between the solar wind and the Earth's magnetic field. The magnetopause moves earthward as the total pressure just inside the magnetopause is reduced or the total pressure just outside the magnetopause is enhanced. It has been suggested for more than four decades that field‐aligned currents, created by magnetic reconnection for southward interplanetary magnetic field, reduce the magnetic pressure just inside the magnetopause. Under the assumption of a constant total pressure just outside the magnetopause, the magnetopause consequently moves earthward. Here we show that the reduced magnetic pressure just inside the magnetopause is insufficient to account for its earthward motion to its real location. For this to happen, an enhancement in the total pressure just outside the magnetopause is required. Our observations also reveal that the enhanced thermal pressure is the major contributor to the total pressure enhancement.
On the numerical simulation of particle dynamics in the radiation belt: 1. Implicit and semi‐implicit schemes
Authors: Camporeale E. , Delzanno G. L. , Zaharia S. , Koller J.
Published: April 2013

The particle dynamics in the Earth's radiation belt is generally modeled by means of a two‐dimensional diffusion equation for the particle distribution function in energy and pitch angle. The goal of this paper is to survey and compare different numerical schemes for the solution of the diffusion equation, and to outline the optimal strategy from a numerical point of view. We focus on the general (and more computationally challenging) case where the mixed terms in the diffusion tensor are retained. In Part 1, we compare fully implicit and semi‐implicit schemes. For the former, we have analyzed a direct solver based on a LU decomposition routine for sparse matrices, and an iterative incomplete LU preconditioned Generalized Minimal REsidual solver. For the semi‐implicit scheme, we have studied an alternating direction implicit scheme. We present a convergence study for a realistic case that shows that the time step and grid size are strongly constrained by the desired accuracy of the solution. We show that the fully implicit scheme is to be preferred in most cases as the more computationally efficient.
ARTEMIS observations of lunar dayside plasma in the terrestrial magnetotail lobe
Authors: Harada Y. , Machida S. , Halekas J. S. , Poppe A. R. , McFadden J. P.
Published: April 2013

We report observations by the dual‐probe Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) mission of Moon‐related electron and ion signatures obtained above the dayside lunar surface in the terrestrial magnetotail lobes. While the Moon is often thought of as a passive absorber, recent observations from Kaguya, Chandrayaan, Chang'E, and ARTEMIS indicate that plasma of lunar origin can have significant effects on the near‐lunar environment. We now present new observations from ARTEMIS showing that lunar plasma can play a dominant role in the low‐density environment of the terrestrial magnetotail. Two‐point observations reveal that the density of plasma of lunar origin is higher than that of the ambient lobe plasma even several hundreds of kilometers above the Moon's dayside. Meanwhile, the distributions of incoming electrons exhibit modifications correlated with Moon‐related populations, suggesting direct or indirect interactions of the lobe electrons with plasma of lunar origin. We also observe high‐energy photoelectron emission from the dayside lunar surface, supporting the existence of large positive potentials on the lunar surface. Pickup ions with nonzero parallel‐velocity components provide further evidence for positive surface potentials of tens of volts or more. ARTEMIS data reveal not only the existence of the positive surface potentials much larger than those predicted from a current‐balance model based on Maxwellian plasmas but also their significant implications for the dynamics of both the dominant Moon‐originating ions and the tenuous ambient plasma populations in the tail lobe.
The impact of the melting layer on the passive microwave cloud scattering signal observed from satellites: A study using TRMM microwave passive and active measurements
Authors: Galligani V. S. , Prigent C. , Defer E. , Jimenez C. , Eriksson P.
Published: April 2013

Concurrent passive and active microwave measurements onboard the Tropical Rainfall Measurement Mission (TRMM) show that under cloudy conditions, when a melting layer is detected by the precipitation radar, a polarized scattering signal at 85 GHz in passive mode is often observed. Radiative transfer simulations confirm the role of large horizontally oriented non‐spherical particles on the polarized scattering signal and assess the effect of changes in particle phase, from solid ice to dry snow to melting snow, on the radiative properties. We conclude on the necessity to account for this polarization generated by the clouds in passive microwave rain retrievals and to use this specific signature to help diagnose the precipitation type and derive more accurate algorithms. In addition, analysis of the passive microwave polarized scattering is a unique way to get insight into microphysical properties of clouds at global scale, and this potential should be explored at millimeter and submillimeter frequencies that are more sensitive to the scattering generated by smaller particles.
Scale space methods for climate model analysis
Authors: Marvel K. , Ivanova D. , Taylor K. E.
Published: April 2013

In this paper, we introduce methods for evaluating climate model performance across spatial scales. These techniques are based on the “scale space” framework widely used in the image processing and computer vision communities. We discuss why the diffusion equation on the sphere provides a particularly attractive means of smoothing two‐dimensional maps of global climate data. We establish that no structure is introduced into a map as an artifact of the smoothing procedure. This allows for the comparison of models and observations at multiple scales. As a test case for these methods, we compare the ability of high‐ and low‐resolution versions of the Community Climate System Model (CCSM) to simulate the seasonal climatologies of surface air temperature (TAS), sea level pressure (PSL), and total precipitation rate (PR). For TAS, we find that the high‐resolution model is better able to capture the boreal summer (JJA) climatological pattern at fine scales, although there is no such improvement in winter (DJF). We find the performances of the high‐ and low‐resolution models to be similarly capable of capturing the summertime sea level pressure climatology at all scales. However, the high‐resolution model PSL climatology is degraded for DJF, especially at larger scales. For both JJA and DJF precipitation climatologies, we find larger precipitation errors in the high‐resolution model at the finest scales; however, performance at larger scales is improved.
Effects of riparian vegetation on topographic change during a large flood event, Rio Puerco, New Mexico, USA
Authors: Perignon M. C. , Tucker G. E. , Griffin E. R. , Friedman J. M.
Published: April 2013

The spatial distribution of riparian vegetation can strongly influence the geomorphic evolution of dryland rivers during large floods. We present the results of an airborne lidar differencing study that quantifies the topographic change that occurred along a 12 km reach of the Lower Rio Puerco, New Mexico, during an extreme event in 2006. Extensive erosion of the channel banks took place immediately upstream of the study area, where tamarisk and sandbar willow had been removed. Within the densely vegetated study reach, we measure a net volumetric change of 578,050 ± ∼ 490,000 m3, with 88.3% of the total aggradation occurring along the floodplain and channel and 76.7% of the erosion focusing on the vertical valley walls. The sediment derived from the devegetated reach deposited within the first 3.6 km of the study area, with depth decaying exponentially with distance downstream. Elsewhere, floodplain sediments were primarily sourced from the erosion of valley walls. Superimposed on this pattern are the effects of vegetation and valley morphology on sediment transport. Sediment thickness is seen to be uniform among sandbar willows and highly variable within tamarisk groves. These reach‐scale patterns of sedimentation observed in the lidar differencing likely reflect complex interactions of vegetation, flow, and sediment at the scale of patches to individual plants.
The Effect of Wait Times on Oncological Outcomes From Periampullary Adenocarcinomas
Authors: McLEAN SPENCER R. , KARSANJI DIVYA , WILSON JENNIFER , DIXON ELIJAH , SUTHERLAND FRANCIS R. , PASIEKA JANICE , BALL CHAD , BATHE OLIVER F.
Published: April 2013

Background:

Overall few patients presenting with periampullary adenocarcinomas have resectable lesions. We postulated that rapid diagnosis and treatment would enhance the likelihood of successful resection, improving survival.

Methods:

A retrospective analysis of patients undergoing surgery for resection of a pancreatic or periampullary lesion was conducted. Resection rate, disease stage and survival were evaluated as a function of wait times.

Results:

Pancreatic resections were booked in 355 patients. Of 193 patients with periampullary adenocarcinomas, 119 patients (61.7%) had resectable disease. There was no difference in median time from initial physician consultation to surgery in patients with resectable and unresectable disease (61 days vs. 64 days, respectively). The likelihood of successful resection was virtually identical in patients with wait times ≤30 and >30 days (from surgical consultation to procedure). There was a trend toward a higher T‐stage in patients who waited >30 days for surgery (P = 0.055). However, there was no difference in survival as a function of wait time.

Conclusions:

This series does not demonstrate an advantage for rapid diagnosis and surgery, in terms of resection rate and survival. However, further study is required in a larger cohort of patients, to confirm these findings. J. Surg. Oncol. 2013;107:853–858. © 2013 Wiley Periodicals, Inc.
A Randomized Controlled Trial to Optimize Indocyanine Green‐Augmented Diode Laser Therapy of Capillary Malformations
Authors: Klein Annette , Bäumler Wolfgang , Buschmann Marius , Landthaler Michael , Babilas Philipp
Published: April 2013

Background

Indocyanine green (ICG)‐augmented diode laser therapy (ICG + DL) represents a new treatment modality for capillary malformations (CM). However, an increase of the ICG‐concentration or the use of an intense pulsed light (IPL) device as light source may further optimize treatment outcomes in CM.

Objective

: This proof‐of‐concept trial including 15 patients (skin type II to III) with CM evaluated the efficacy and safety of ICG‐augmented diode laser therapy (808 nm) at a total dose of 4 mg/kg body weight (b.w.). Additionally, five patients with extensive CM received IPL therapy before and after ICG‐administration (ICG + IPL).

Methods

ICG was intravenously administered to 15 patients with CM at a total dose of 4 mg/kg b.w. Immediately after ICG injection, diode laser pulses with different radiant exposures (20–110 J/cm2) were applied as one single treatment. Five patients with extensive CM additionally received IPL (555–950 nm) therapy. Safety and efficacy were assessed both 1 and 3 months after the single treatment by a blinded investigator and the patient. Furthermore, color of the CM was objectively measured by means of a color meter (colorStriker™, Eduard Mathai GmbH, Hannover, Germany). Treatment with the flashlamp‐pumped pulsed dye laser (FPDL) and the IPL alone (five patients) served as reference treatment.

Results

According to the assessment by the patients and the blinded investigator, the clearance rate was slightly better after ICG + DL therapy than after FPDL treatment (P = 0.1, P = 0.8). In one out of five patients, IPL with and without ICG injection induced poor to moderate clearance of CM and persisting erythema in another patient. The correlation between the visual assessment by the blinded investigator and the colorimetric measurements was poor.

Conclusion

A minority of patients with CM may benefit from ICG + DL therapy, but efficacy cannot be improved by higher ICG doses. Lasers Surg. Med. 9999:XX–XX, 2013. © 2013 Wiley Periodicals, Inc.
New Thiols for Photoinitiator‐Free Thiol‐Acrylate Polymerization
Authors: Tehfe Mohamad‐Ali , Mondal Shovan , Nechab Malek , Dumur Frédéric , Bertrand Michèle P. , Graff Bernadette , Gigmes Didier , Fouassier Jean‐Pierre , Lalevée Jacques
Published: April 2013

New thiols for efficient thiol‐ene polymerization reactions are presented. They do not exhibit any unpleasant odor, are characterized by quite good light‐absorption properties at λ > 300 nm, and generate thiyl radicals upon UV‐light exposure. Due to these interesting properties and contrary to many previously reported methodologies, the present thiol‐acrylate polymerizations can be efficiently carried out without the presence of any additional photoinitiator. The chemical mechanisms are investigated by steady‐state photolysis and electron spion resonance (ESR) experiments. Important parameters can also be extracted from molecular orbital calculations.

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A low‐power technique to boost the output amplitude of multi gigahertz push‐push LC VCOS
Authors: Molavi Reza , Mirabbasi Shahriar , Djahanshahi Hormoz
Published: April 2013

A design technique to increase the output amplitude and hence the output power of push‐push LC‐based voltage‐controlled oscillators (LC VCOs) is presented that relies on LC resonance boosting of the second harmonic. Measurement results are in good agreement with the results predicted from the analysis. Using the proposed technique, a low‐power push‐push LC VCO is designed and implemented in 90‐nm CMOS. Based on the measurement results, the VCO has a frequency tuning range of 23%, from 20.1 to 24.8 GHz. It exhibits up to 8 dB improvement in its output power at the middle of the frequency band compared to a traditional push‐push VCO. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1581–1584, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27599
Modeling the package of a LNA with a 3D‐EM simulator
Authors: García‐Vázquez Hugo , Khemchandani Sunil L. , Ramos‐Valido Dailos , Orbaiceta‐Ezcurra Krisnaya , del Pino Javier
Published: April 2013

In this work, the package influence on a feedback low‐noise amplifier has been studied.The electromagnetic simulator of ADS was used to obtain the QFN16 package model and the bonding model. The influence of the package and the pad on the supply node was negligible when it was studied separately. However, the circuit performance is reduced when the inductance introduced by the bonding of the supply node is combined with the parasitic capacities associated to the pad with electrostatic discharge protection. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1435–1440, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27601
Design of compact circularly polarized radio frequency identification tag antenna for metallic object application
Authors: Chen Horng‐Dean , Kuo Shang‐Huang , Jheng Jing‐Lun
Published: April 2013

A passive UHF band radio frequency identification tag antenna design is presented in this article. To allow compact size and circular polarization (CP) radiation, a radiating square patch is loaded with two pairs of unequal slits, while a quarter‐wave microstrip line connected to a tag chip and terminated by a short‐circuited stub line is used to excite the radiating patch. The 10‐dB impedance bandwidth of the tag antenna is measured to be 31 MHz (896–927 MHz), whereas its 3‐dB CP bandwidth is 6 MHz (911–917 MHz). Further experiment has demonstrated that the proposed tag antenna can provide better reading distance when mounted on a metallic surface as compared with the free‐space condition. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1481–1485, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27607
A reactive power sensor based on fiber Bragg grating and a piezo‐electric transducer
Authors: Cheng Chin‐Hsing , Cheng Kuo‐Liang , Liu Wen‐Fung
Published: April 2013

This article develops an optical fiber sensor using a fiber Bragg grating (FBG) and a piezo‐electrical transducer (PZT) to measure reactive power. By mounting an FBG on a PZT bar, a dynamic strain simulator was constructed. The equivalent voltage produced by reactive power applied to the PZT was converted to the dynamic variation of the FBG Bragg wavelength. The reactive power was attained by measuring the changing value of the wavelength. Thus, the sensor can be used to measure reactive power without the use of a traditional power meter. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1692–1696, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27617
CPW‐FED UWB antenna with band‐stop properties
Authors: Pouyanfar Negin
Published: April 2013

Structurally simple and miniaturized ultra wideband (UWB) printed rectangular antenna fed by a coplanar waveguide (CPW) is proposed.Overall dimension of the antenna is as compact as 12 (0.13λ) × 12 (0.13λ) × 1.6 mm3, where λ is the wavelength of the first resonance of the antenna. The main feature of the proposed antenna is its compact size and controllable structure which lead to four different antenna designs. By adjusting the dimensions of the elements of the antenna, notch frequency in different ranges of the UWB can be obtained. The resulting VSWR < 1.5 impedance bandwidth is as large as 11.6 GHz. The antenna presents a stable gain and omnidirectional radiation pattern in its operational frequencies. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1533–1537, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27624
Bandwidth enhancement of an ultra‐wideband printed slot antenna with WLAN band‐notched function
Authors: Ojaroudi Nasser , Ojaroudi Mohammad
Published: April 2013

In this article, a compact ultra‐wideband (UWB) slot antenna with band‐notched performance is presented. To increase the impedance bandwidth of an ordinary slot antenna, we use a pair of S‐shaped slots in the ground plane that with this structure a new resonance at the higher frequencies can be achieved, and a wide usable fractional bandwidth of more than 130% is provided. Additionally, by cutting a rectangular slot with a rotated E‐shaped strip protruded inside the slot in the square radiating stub, a frequency‐notched band performance has been obtained. The designed antenna has a small size of 20 × 20 mm2 while showing the radiation performance in the frequency band of 3.13 to over 14.3 GHz with a band rejection performance in the frequency band of 5–6 GHz. Simulated and experimental results obtained for this antenna show that it exhibits good radiation behavior within the UWB‐frequency range. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1448–1451, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27631
Compact multiband printed‐IFA on electromagnetic band‐gap structures ground plane
Authors: Elsheakh Dalia M. , Abdallah Esmat A.
Published: April 2013

Fourth mobile generation requiring of multistandard operating handsets of small physical size as well as increasing demand for higher data rates.Compact multiband printed inverted‐F antennas (IFA) for available wireless communications are proposed in this article. New design of printed IFA based on uniplanar compact electromagnetic band gap (EBG) concept is proposed. A printed‐IFA with L‐loaded shaped over artificial ground plane is designed as the main antenna to cover the GSM, LTE, UMTS, Bluetooth, and WLAN. The multiband is created by means of an EBG structure that is used as a ground plane. Different shapes of uniplanar EBG as ring, split ring resonator, and spiral rather than mushroom‐like structure are investigated. The proposed antenna is built on the uniplanar EBG ground plane with size of 35 × 45 mm2, which is suitable for most of the mobile devices. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1670–1676, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27633
Novel splicing technique for coated optical fiber connection without stripping or cleaning process
Authors: Kihara Mitsuru , Koyama Ryo , Son Hitoshi , Tomita Shigeru
Published: April 2013

We propose a new splicing technique by precisely aligning and directly connecting coated fibers with a capillary. The assembled splice for 1.3‐μm single‐mode fibers with an 80 μm cladding and a 125 μm coating can provide a low insertion loss of 0.2 dB and a high return loss of over 46 dB. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1453–1456, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27636
1‐Watt highly linear HBT power amplifier driver integrated circuit with low current consumption
Authors: Joo S. , Han S. , Song M. , Kim H. , Ham J. , Seo M. , Kim M. , Park C. , Yang Y.
Published: April 2013

This article presents a power amplifiers (PA) driver IC which has a parallel combined structure with a dual bias network.Each PA cell for parallel combination has an optimized bias to achieve both lower current consumption and IM3 cancellation at the same time, so that the overall PA driver IC has an improved linearity with a low current consumption. An incomplete Wilkinson divider including an input matching capability was proposed. This was adopted to prevent a stability degradation which can be caused by a parallel combination. The proposed PA driver IC was designed. This was implemented using a 2‐μm InGaP/GaAs heterojunction bipolar transistor (HBT) to have an output power of 1 Watt. The quiescent currents for the upper and lower PA cells were optimized to have the best compromised performances with quiescent current levels of 100 and 150 mA, respectively. By the implemented PA driver IC, a gain of 17.25 dB and a high power‐added efficiency of 54.15% at a P1dB of 31 dBm were achieved at a center frequency of 900 MHz. For a two‐tone signal having a tone‐spacing of 1 MHz, it also exhibited a high output IP3 of 54.28 dBm at an output power level of 20 dBm. The average output power was 22.36 dBm to which the IMD3 level should be lower than −60 dBc. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1680–1683, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27639
Performance enhancement of a circularly polarized patch antenna for radio frequency identification readers using an electromagnetic band‐gap ground plane
Authors: Pflaum Sylvain , Thuc Philippe Le , Kossiavas Georges , Staraj Robert
Published: April 2013

A miniaturized circularly polarized (CP) patch antenna with wide impedance matching and axial ratio bandwidths and a good efficiency using an electromagnetic band gap (EBG) ground plane is presented. CP is obtained with the truncated corners technique applied on a square patch and size reduction of this radiating element is based on the slow wave phenomenon created in the EBG structure. This antenna is fabricated on a 117 × 117 × 4 mm3 FR‐4 substrate (εT = 4.4 and tan δ = 0.22) and dedicated to the European UHF radio frequency identification band (865–868 MHz). The measured bandwidth, realized gain, and total efficiency are 14.4%, 3.7 dBi, and 79%, respectively. Experimental and theorical results are presented and discussed. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1599–1602, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27642
Optimization of a broadband VHF lumped‐element ferrite circulator
Authors: Smith Jacob R. , Dong Hang , Young Jeffrey L. , Aldecoa Brandon
Published: April 2013

A multistage optimization procedure is provided to maximize the operating bandwidth of a very high frequency circulator. We show through hardware validation that bandwidths on the order of 52.3–80.9 MHz are achievable using a 15 dB isolation specification. Simulation studies indicate that bandwidths on the order of 100% are possible, but such wideband performance has not been achieved in hardware to date. The optimization procedure uses both genetic algorithms and orthogonal sweep methods to find the best crossover geometry and ferrite properties, but the outcome of both methods is roughly the same. Matching networks are used to tune the response and to widen the operating frequency band. These networks are optimized using Pareto tradeoff charts in the context of power metrics like return loss, isolation, and insertion loss. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1476–1481, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27654
Double diffraction and double reflection in NURBS‐UTD method
Authors: Wang Nan , Du XinXin , Wang Yong , Liang ChangHong
Published: April 2013

Double diffraction and double reflection in NURBS‐UTD method are studied in this article. Algorithms being used to trace double reflected rays and double edge diffracted rays are presented. The ray fields carried by these kinds of rays are investigated to discuss the contribution of the double effected ray fields to the total ray fields. Numerical measures are used throughout the whole process and the ray fields are calculated based on single effected ray fields. Two examples are presented and it can be seen from data achieved that double effected ray fields can improve the computational precision according to the relationship between surfaces. Numerical results show the validation and the improvement. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1549–1553, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27652
Decoupled WWAN/LTE antennas with an isolation ring strip embedded therebetween for smartphone application
Authors: Wong Kin‐Lu , Lin Po‐Wei , Hsu Hung‐Jen
Published: April 2013

An integrated antenna array comprising two decoupled multiband WWAN/LTE antennas having an isolation ring strip embedded therebetween and all disposed on a same FR4 substrate of small size 10 × 70 mm2 is presented. The two decoupled antennas cover the 824–960/1710–2690 MHz bands for the GSM850/900 and GSM1800/1900/UMTS/LTE2300/2500 operations and are promising to be mounted at the bottom edge of a smartphone for dual wireless wide area network (WWAN) operation for dual‐talk function or for long term evolution (LTE) multiple‐input multiple‐output operation. The measured transmission coefficient S21 between the two antennas is less than −15 dB over both the 824–960 and 1710–2690 MHz bands, and the envelop correlation coefficient is less than about 0.03 over both bands. Port‐decoupling of the two antennas is obtained because the excited surface currents on the system ground plane of the smartphone between the two antennas are decreased owing to the isolation ring strip attracting some of the same. In addition to good isolation obtained, the antenna efficiencies are better than about 40 and 50% over the lower and upper bands, respectively. Details of the decoupled WWAN/LTE antennas are described. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1470–1476, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27654
Dual band bandpass filter using coupled and series capacitors with controllable bandwidths
Authors: Lu Yun‐Long , Dai Gao‐Le , Li Kai
Published: April 2013

In this article, a novel compact dual‐band bandpass filter with controllable bandwidths is presented. A set of central‐loaded resonators are employed to generate dual band responses. Three coupled‐capacitors, loaded at the corresponding voltage‐zero points of the resonators, are utilized to control the coupling coefficients of two bands separately. Besides, two extra series capacitors, between feed lines and resonators, are adopted to simultaneously achieve the desired external quality factors of dual passbands. Thus, the bandwidths of the dual bands can be independently controlled. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1543–1546, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27665
Design of multishell sampling schemes with uniform coverage in diffusion MRI
Authors: Caruyer Emmanuel , Lenglet Christophe , Sapiro Guillermo , Deriche Rachid
Published: April 2013

Purpose:

In diffusion MRI, a technique known as diffusion spectrum imaging reconstructs the propagator with a discrete Fourier transform, from a Cartesian sampling of the diffusion signal. Alternatively, it is possible to directly reconstruct the orientation distribution function inq‐ball imaging, providing so‐called high angular resolution diffusion imaging. In between these two techniques, acquisitions on several spheres in q‐space offer an interesting trade‐off between the angular resolution and the radial information gathered in diffusion MRI. A careful design is central in the success of multishell acquisition and reconstruction techniques.

Methods:

The design of acquisition in multishell is still an open and active field of research, however. In this work, we provide a general method to design multishell acquisition with uniform angular coverage. This method is based on a generalization of electrostatic repulsion to multishell.

Results:

We evaluate the impact of our method using simulations, on the angular resolution in one and two bundles of fiber configurations. Compared to more commonly used radial sampling, we show that our method improves the angular resolution, as well as fiber crossing discrimination.

Discussion:

We propose a novel method to design sampling schemes with optimal angular coverage and show the positive impact on angular resolution in diffusion MRI. Magn Reson Med 69:1534–1540, 2013. © 2013 Wiley Periodicals, Inc.
Update on pediatric cancer predisposition syndromes
Authors: Schiffman Joshua D. , Geller James I. , Mundt Erin , Means Anthony , Means Lindsey , Means Von
Published: April 2013

Hereditary cancer syndromes in children and adolescents are becoming more recognized in the field of pediatric hematology/oncology. A recent workshop held at the American Society of Pediatric Hematology/Oncology (ASPHO) 2012 Annual Meeting included several interactive sessions related to specific familial cancer syndromes, genetic testing and screening, and ethical issues in caring for families with inherited cancer risk. This review highlights the workshop presentations, including a brief background about pediatric cancer predisposition syndromes and the importance of learning about them for the practicing pediatric hematologists/oncologists. This is followed by a brief summary of the newly described cancer predisposition syndromes including Rhabdoid Tumor Predisposition Syndrome, Hereditary Paragangliomas and Pheochromocytoma Syndrome, and Familial Pleuropulmonaryblastoma Tumor Predisposition (DICER1) Syndrome. The next section covers genetic testing and screening for pediatric cancer predisposition syndromes. Ethical issues are also discussed including preimplantation genetic diagnosis or testing (PGD/PGT), suspicious lesions found on tumor screening, and incidental mutations discovered by whole genome sequencing. Finally, the perspective of a family with Li‐Fraumeni Syndrome is shared. Pediatr Blood Cancer 2013;60:1247–1252. © 2013 Wiley Periodicals, Inc.
Maternal medication and herbal use and risk for hypospadias: data from the National Birth Defects Prevention Study, 1997–2007
Authors: Lind Jennifer N. , Tinker Sarah C. , Broussard Cheryl S. , Reefhuis Jennita , Carmichael Suzan L. , Honein Margaret A. , Olney Richard S. , Parker Samantha E. , Werler Martha M. ,   for the National Birth Defects Prevention Study
Published: April 2013

Purpose

To investigate associations between maternal use of common medications and herbals during early pregnancy and risk for hypospadias in male infants.

Methods

We used data from the National Birth Defects Prevention Study, a multi‐site, population‐based, case–control study. We analyzed data from 1537 infants with second‐degree or third‐degree isolated hypospadias and 4314 live‐born male control infants without major birth defects, with estimated dates of delivery from 1997 to 2007. Exposure was reported use of prescription or over‐the‐counter medications or herbal products, from 1 month before to 4 months after conception. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, adjusting for maternal age, race/ethnicity, education, pre‐pregnancy body mass index, previous live births, maternal subfertility, study site, and year.

Results

We assessed 64 medication and 24 herbal components. Maternal uses of most components were not associated with an increased risk of hypospadias. A new associations was observed for venlafaxine (aOR 2.4; 95%CI 1.0, 6.0) [Correction made here after initial online publication.]. The previously reported association for clomiphene citrate was confirmed (aOR 1.9; 95%CI 1.2, 3.0). Numbers were relatively small for exposure to other specific patterns of fertility agents, but elevated aORs were observed for the most common of them.

Conclusions

Overall, findings were reassuring that hypospadias is not associated with most medication components examined in this analysis. New associations will need to be confirmed in other studies. Increased risks for hypospadias associated with various fertility agents raise the possibility of confounding by underlying subfertility. Copyright © 2013 John Wiley & Sons, Ltd.
Time until incident dementia among Medicare beneficiaries using centrally acting or non‐centrally acting ACE inhibitors
Authors: Hebert Paul L. , McBean Alexander Marshall , O'Connor Heidi , Frank Barbara , Good Charles , Maciejewski Matthew L.
Published: April 2013

Background

Centrally active (CA) angiotensin‐converting enzyme inhibitors (ACEIs) are able to cross the blood–brain barrier. Small observational studies and mouse models suggest that use of CA versus non‐CA ACEIs is associated with a reduced incidence of Alzheimer's disease and related dementias (ADRD).

Objective

The aim of this research was to assess the effect of CA versus non‐CA ACEI use on incident ADRD.

Design

This is a retrospective cohort study with a non‐equivalent control group.

Setting and patients

This study used a national random sample of Medicare beneficiaries enrolled in Part D with an ACEI prescription. A prevalent ACEI user cohort included beneficiaries (n = 107 179) with an ACEI prescription prior to 30 April 2007; beneficiaries without an ACEI prescription before this date were defined as incident ACEI users (n = 9840).

Measurements

The main outcome was time until first diagnosis of ADRD in Medicare claims.

Results

The unadjusted, propensity‐matched and instrumental variable analyses of both the prevalent and incident ACEI user cohorts consistently showed similar time until incident ADRD in those taking CA ACEIs compared with those who took non‐CA ACEIs.

Limitations

The limitations of this study include the use of observational data, relatively short follow‐up time and claims‐based measure of cognitive decline.

Conclusions

In this analysis of Medicare beneficiaries who were prevalent or incident users of ACEIs in 2007–2009, the use of CA ACEIs was unrelated to cognitive decline within 3 years of index prescription. Continued follow‐up of these patients and more sensitive measures of cognitive decline are necessary to determine whether a cognitive benefit of CA ACEIs is realized in the long term. Copyright © 2013 John Wiley & Sons, Ltd.