bluuebunny/crossref_metadata_2025 huggingface dataset:
Degradation rate of sodium fluoroacetate in three New Zealand soils
Authors: Northcott Grant , Jensen Dwayne , Ying Lucia , Fisher Penny
Published: January 2014

The degradation rate of sodium fluoroacetate (SFA) was assessed in a laboratory microcosm study incorporating 3 New Zealand soil types under different temperature (5 °C, 10 °C, or 20 °C) and soil moisture (35% or 60% water holding capacity) conditions using guideline 307 from the Organisation for Economic Co-operation and Development. A combination of nonlabeled and radiolabeled 14C-SFA was added to soil microcosms, with sampling and analysis protocols for soil, soil extracts, and evolved CO2 established using liquid scintillation counting and liquid chromatography–mass spectrometry. Degradation products of SFA and their rates of formation were similar in the 3 soil types. The major degradation pathway for SFA was through microbial degradation to the hydroxyl metabolite, hydroxyacetic acid, and microbial mineralization to CO2, which constituted the major transformation product. Temperature, rather than soil type or moisture content, was the dominant factor affecting the rate of degradation. Soil treatments incubated at 20 °C displayed a more rapid loss of 14C-SFA residues than lower temperature treatments. The transformation half-life (DT50) of SFA in the 3 soils increased with decreasing temperature, varying from 6 d to 8 d at 20 °C, 10 d to 21 d at 10 °C, and 22 d to 43 d at 5 °C. Environ Toxicol Chem 2014;33:1048–1058. © 2014 SETAC
Soil genotoxicity induced by successive applications of chlorothalonil under greenhouse conditions
Authors: Jin Xiangxiang , Cui Ning , Zhou Wei , Khorram Mahdi Safaei , Wang Donghong , Yu Yunlong
Published: January 2014

Greenhouse production of vegetables has been developed rapidly in China. High temperature and humidity inside the greenhouse make this environment more suitable for fast reproduction of fungal diseases. Fungicides are among the chemicals used extensively in the greenhouse to prevent crops from invasive infections by phytopathogens; however, little is known about the accumulation of fungicides in soil and their effect on soil quality under greenhouse conditions. In the present study, the accumulation of the fungicide chlorothalonil (CT) and its toxic metabolite hydroxy-chlorothalonil (HCT) in soil as well as their related soil genotoxicity under greenhouse conditions was investigated. The results indicated that both CT and HCT accumulated in soil with repeated applications of CT, and the accumulation level was strongly correlated to application dosage and its frequency. In addition, soil genotoxicity, which was measured by Vicia faba, also increased with the accumulation of CT and HCT, and the main contributor to this phenomenon was CT rather than HCT. The data demonstrated that successive applications of fungicides may result in their accumulation in soil and thus a decline in soil quality. Environ Toxicol Chem 2014;33:1043–1047. © 2014 SETAC
How Informed Investors Take Advantage of Negative Information in Options and Stock Markets
Authors: Kang Jangkoo , Park Hyoung‐Jin
Published: January 2014

We examine whether and how investors establish positions in options when they have negative information in the U.S. markets from August 2004 to January 2009. Our empirical results show that options seem to be actively and effectively used for the exploitation of negative information. General trading volumes and bid–ask spreads of options remarkably increase like those of stocks as the short sellers increase their selling pressure. Notably, we find that the difference between a stock's traded price and its implied price from the options market reaches its peak about 2 weeks before the short sale trading activity reaches its peak. We also observe that synthetic short positions measured by this difference are preferred over OTM put positions by investors with negative information. Finally, economically significant returns based on a strategy using the difference in the traded and implied stock prices as a trading signal support our evidence. Moreover, these profits confirm the findings of the previous research which argue that options are shelters for informed investors. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 34:516–547, 2014
Synthesis and Crystal Structure of a New Salt of the Water‐Stable Hexathiohypodiphosphate Anion: [py2Li]4[P2S6] ·2 py
Authors: Schönberger Stefanie , Rotter Christiane , Karaghiosoff Konstantin
Published: January 2014

A new rare example of a synthetic route in solution to the hexathiohypodiphosphate anion P2S64− is presented. Starting from P4S3, Li2S, and elemental sulfur in pyridine, this reaction yields yellow block‐shaped crystals of [py2Li]4[P2S6] · 2 py (1). The molecular structure of this hitherto unknown compound was determined by single crystal X‐ray diffraction and reveals a heteronorbornane skeleton within the Li4P2S6 entity.
Evaluating the impacts of climate change and switchgrass production on a semiarid basin
Authors: Goldstein Justin C. , Tarhule Aondover
Published: January 2014

Climate and land use changes greatly modify hydrologic regimes. In this paper, we modelled the impacts of biofuel cultivation in the US Great Plains on a 1061‐km2 watershed using the Soil and Water Assessment Tool (SWAT) hydrologic model. The model was calibrated to monthly discharges spanning 2002–2010 and for the winter, spring, and summer seasons. SWAT was then run for a climate‐change‐only scenario using downscaled precipitation and a projected temperature for 16 general circulation model (GCM) runs associated with the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios A2 scenario spanning 2040–2050. SWAT was also run on a climate change plus land use change scenario in which Alamo switchgrass (Panicum virgatum L.) replaced native range grasses, winter wheat, and rye (89% of the basin). For the climate‐change‐only scenario, the GCMs agreed on a monthly temperature increase of 1–2 °C by the 2042–2050 period, but they disagreed on the direction of change in precipitation. For this scenario, decreases in surface runoff during all three seasons and increases in spring and summer evapotranspiration (eT) were driven predominantly by precipitation. Increased summer temperatures also significantly contributed to changes in eT. With the addition of switchgrass, changes in surface runoff are amplified during the winter and summer, and changes in eT are amplified during all three seasons. Depending on the GCM utilized, either climate change or land use change (switchgrass cultivation) was the dominant driver of change in surface runoff while switchgrass cultivation was the major driver of changes in eT. Copyright © 2014 John Wiley & Sons, Ltd.
First in vivo visualization of MRI‐visible IPOM in a rabbit model
Authors: Otto Jens , Kuehnert Nicolas , Kraemer Nils A. , Ciritsis Alexander , Hansen Nienke Lynn , Kuhl Christiane , Busch Daniel , Peter Neumann Ulf , Klinge Uwe , Conze Klaus‐Joachim
Published: January 2014

Background: Application of a mesh in presence of pneumoperitoneum may cause deformation or wave formation when gas is released. Moreover, mesh shrinkage during subsequent wound healing cannot be detected in vivo without invasive diagnostics. Using MRI‐visible polyvinylidene fluoride (PVDF) mesh, the extend of mesh deformation and shrinkage could be objectified by MRI for the first time. Materials and Methods: Laparoscopic intraperitoneal onlay mesh (IPOM) implantation was performed in 10 female rabbits using ferro‐oxide loaded PVDF meshes. MRI measurements were performed postoperatively at days 1 and 90. After three‐dimensional reconstruction of all MRI images the total surface and the effective surface of the implanted mesh were explored and calculated computer‐assisted. Results: In all cases, the mesh could be identified in MRI. The subsequent three‐dimensional reconstruction always allowed a calculation of the mesh area. In relation to the original size of the used textile implant, we found neither a significant reduction of the effective mesh surface after release of the pneumoperitoneum at day 1 after laparoscopic surgery nor a significant change of the total surface of this large pore mesh by the end of the observation period. Conclusions: In vivo investigation of mesh surface via MRI could exclude a significant initial reduction of the effective mesh surface after release of pneumoperitoneum, in this IPOM rabbit model. A further subsequent shrinkage of these large pore PVDF meshes could be excluded, as well. Imaging of MRI‐visible IPOM mesh turned out to be a sufficient tool to objectify mesh configuration and position in vivo. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1165–1169, 2014.
Bone Matrix Quality After Sclerostin Antibody Treatment
Authors: Ross Ryan D , Edwards Lindsey H , Acerbo Alvin S , Ominsky Michael S , Virdi Amarjit S , Sena Kotaro , Miller Lisa M , Sumner D Rick
Published: January 2014

Sclerostin antibody (Scl-Ab) is a novel bone-forming agent that is currently undergoing preclinical and clinical testing. Scl-Ab treatment is known to dramatically increase bone mass, but little is known about the quality of the bone formed during treatment. In the current study, global mineralization of bone matrix in rats and nonhuman primates treated with vehicle or Scl-Ab was assayed by backscattered scanning electron microscopy (bSEM) to quantify the bone mineral density distribution (BMDD). Additionally, fluorochrome labeling allowed tissue age–specific measurements to be made in the primate model with Fourier-transform infrared microspectroscopy to determine the kinetics of mineralization, carbonate substitution, crystallinity, and collagen cross-linking. Despite up to 54% increases in the bone volume after Scl-Ab treatment, the mean global mineralization of trabecular and cortical bone was unaffected in both animal models investigated. However, there were two subtle changes in the BMDD after Scl-Ab treatment in the primate trabecular bone, including an increase in the number of pixels with a low mineralization value (Z5) and a decrease in the standard deviation of the distribution. Tissue age–specific measurements in the primate model showed that Scl-Ab treatment did not affect the mineral-to-matrix ratio, crystallinity, or collagen cross-linking in the endocortical, intracortical, or trabecular compartments. Scl-Ab treatment was associated with a nonsignificant trend toward accelerated mineralization intracortically and a nearly 10% increase in carbonate substitution for tissue older than 2 weeks in the trabecular compartment (p < 0.001). These findings suggest that Scl-Ab treatment does not negatively impact bone matrix quality. © 2014 American Society for Bone and Mineral Research.
Comparative development and evolution of two lateral line phenotypes in lake malawi cichlids
Authors: Webb Jacqueline F. , Bird Nathan C. , Carter Lauren , Dickson Juleen
Published: January 2014

A comparison of the pattern and timing of development of cranial lateral line canals and canal neuromasts in three species of Lake Malawi cichlids, Labeotropheus fuelleborni and Metriaclima zebra (narrow lateral line canals), and Aulonocara baenschi (widened lateral line canals) was used to test the hypothesis that the evolution of widened canals (thought to be an adaptive phenotype in the lateral line system) from narrow canals is the result of heterochrony. Using histological analysis and scanning electron microscopy, this study has provided the first detailed and quantitative description of the development of widened lateral line canals in a teleost, and has demonstrated that: 1) canal neuromast number and the pattern of canal morphogenesis are conserved among species with different adult canal phenotypes, 2) heterochrony (“dissociated heterochrony” in particular) can explain the evolution of widened canals and variation in morphology between canals within a species with respect to canal diameter and neuromast size, and 3) the morphology of the lateral line canals and the dermal bones in which they are found (e.g., the mandibular canal the dentary and anguloarticular bones of the mandible) can evolve independently of each other, thus requiring the addition of another level of complexity to discussions of modularity and integration in the skull of bony fishes. J. Morphol. 275:678–692, 2014. © 2014 Wiley Periodicals, Inc.
The development of the immune tissues in marsupial pouch young
Authors: Borthwick Casey R. , Young Lauren J. , Old Julie M.
Published: January 2014

Current knowledge of the development of the marsupial immune system, particularly in the context of lymphoid tissue development and the appearance of lymphocytes, has been examined and limitations identified. While primary lymphoid tissues like the thymus have been extensively studied, secondary lymphoid tissues such as the spleen and lymph nodes have been examined to a lesser extent, partly due to the difficulty of macroscopically identifying these structures, particularly in very small neonates. In addition, little research has been conducted on the mucosal‐associated lymphoid tissues; tissues that directly trap antigens and play an important role in the maturity of adaptive immune responses. Research on the development of the marsupial immune tissues to date serves as a solid foundation for further research, particularly on the mechanisms behind the development of the immune system of marsupials. With the recent sequencing and annotation of whole marsupial genomes, the current wealth of sequence data will be essential in the development of marsupial specific reagents, including antibodies, that are required to widen our specific knowledge of the complex marsupial immune system and its development. J. Morphol. 275:822–839, 2014. © 2014 Wiley Periodicals, Inc.
Complex permittivity and permeability estimation by reflection measurements of open and short coaxial transmission line
Authors: Staszek Kamil , Gruszczynski Slawomir , Wincza Krzysztof
Published: January 2014

A novel method for complex permittivity and permeability measurements of dielectrics has been shown. The method is based on a previously developed transmission‐line technique, however, has been modified to allow for dielectric properties estimation with measurements of reflections only. The analysis of measurement errors, resulting from: sample length uncertainty, vector network analyzer uncertainty, and open‐end inaccuracy, has been shown in the article. The calibration method using open/short/offset‐short standards has been described. The method has been experimentally tested by measurements of three different reference liquid samples. A good agreement between measured values and previously published ones has been obtained. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:727–732, 2014
5‐Ghz low noise amplifier with ESD protection method using transformer
Authors: Yoon Jaehyuk , Park Changkun
Published: January 2014

In this study, we propose a 5‐GHz differential RF CMOS low noise amplifier (LNA) with electrostatic discharge (ESD) protection method in the RF input and output using spiral transformers. Spiral transformers are used as the ESD protection elements as well as the components of the input and output matching networks. During an ESD event, the transformers become the path through which the ESD current shunts because the frequency of the ESD is much lower than the operating frequency of the general RF circuit. The designed LNA is implemented using a 0.18‐µm RF CMOS process. The measured ESD survival level is higher than 1.4 kV. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:684–689, 2014
Time‐domain gate based on a mach‐zehnder interferometer to reduce amplified spontaneous emissions in a continuously pumped fiber amplifier
Authors: Kuroda Keiji , Yoshikuni Yuzo
Published: January 2014

We report reduction of amplified spontaneous emissions in a continuously pumped fiber amplifier by using a Mach–Zehnder interferometer. A reduction ratio of over 25 dB in the total emission intensity was achieved by using the interferometer. We also measured the dependence of the emission spectra on the bias voltage. Time‐resolved emissions were observed in a dual‐amplifier system containing the interferometer as a time‐domain gate. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:590–594, 2014
A simple penta‐band reconfigurable antenna for mobile device applications
Authors: Lee J. H. , Sung Y.
Published: January 2014

A simple reconfigurable antenna for mobile device applications is proposed in this letter. The proposed structure uses a conventional planar inverted‐F antenna as its basic geometry and a single PIN diode embedded in the middle of the shorting line. The proposed antenna has two resonances (f1 and f2). These resonances are easily controlled by electrically controlling the on/off state of the PIN diode. The measured results show that the basic resonance f1 covers the GSM850 (824–894 MHz) and GSM900 (880–960 MHz) bands in the lower band, and the harmonic resonance f2 includes digital communication system (1710–1880 MHz), personal communication system (1850–1990 MHz), and universal mobile telecommunications system (1920–2710 MHz) bands in the higher band. Therefore, the proposed antenna achieves penta‐band wireless wide area network operation. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:769–774, 2014
Design of dual‐band bandpass filter with constant absolute bandwidth
Authors: Su Tao , Zhang Li‐Juan , Wang Sheng‐Jie , Li Zhi‐Peng , Zhang Yong‐Liang
Published: January 2014

A dual‐band bandpass filter using split‐ring resonators (SRRs) and defected ground structure (DGS) with constant absolute bandwidth is proposed in this article. The inner and outer SRRs are operated for respective passband. DGS is etched on the ground, which can control the coupling coefficient of the filter to maintain constant absolute bandwidth. Finally, such kind of filter with compact size and high selectivity characteristics are designed and fabricated. The simulation and measurement results are basically in good agreement. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:715–718, 2014
An effective third harmonic generator using a left‐handed nonlinear transmisson line
Authors: Kim In Bok , Kim Kang Wook , Yoo Hyoungsuk , Park Jonghoo , Kim Hongjoon
Published: January 2014

In this article, an effective third harmonic generator using a left‐handed nonlinear transmission line (LH NLTL) is presented. The proposed harmonic generator using the LH NLTL is composed of a series of varactor diodes and shunt inductances, which were implemented with a 0.2‐mm wide microstrip line. The harmonic generator was built on a Rogers RO4003 substrate and has dimensions of 12 × 7 mm2. The fabricated LH NLTL provides a maximum insertion loss of 5.2 dB, and a minimum insertion loss of 2.2 dB for a wide frequency band from 2.3 to 18.7 GHz. The measured minimum third harmonic conversion loss was 14.2 dB at an input frequency of 2.5 GHz. When compared to other works, a better third harmonic conversion efficiency is achieved with much smaller size in lower frequencies. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:568–570, 2014
Implementation and justification of a triple frequency‐notched UWB proximity‐fed antenna with shunt stubs
Authors: Ali Mohamed Mamdouh M. , Saad Ayman Ayd R. , Khaled Elsayed Esam M.
Published: January 2014

In this article, an ultrawideband (UWB) antenna with triple band‐rejection characteristics is proposed. The antenna is compact with size of 22.5 × 24 mm2. Matching between a sector‐disk shaped radiating patch and the 50‐Ω microstrip line is manipulated through a proximity‐feed technique. An elliptically‐shaped aperture is etched in the ground plane to enhance the antenna bandwidth. Double shunt stubs are used to get more enhancement of the impedance bandwidth of the antenna. The band notches at WiMAX of 3.3–3.9 GHz, lower WLAN of 5.15–5.35 GHz, and upper WLAN of 5.725–5.825 GHz are realized by embedding three elements; a reversed F‐shaped slot etched off in the patch, a reversed U‐shaped slot etched off in the feed line, and adding a parasitic flipped C‐shaped strip around the patch, respectively. The antenna is fabricated and the experimental data show that the designed antenna has an impedance bandwidth of 3.2–11.6 GHz for VSWR less than 2, except at three frequency stop‐bands of 3.20–4.19, 5.02–5.32, and 5.51–6.10 GHz. Curve fitting formulations to describe the influences of the embedded structures on the corresponding notched frequencies are obtained by using a second‐order polynomial. Moreover, physical lumped elements of an electrical equivalent circuit model of the proposed antenna are obtained using a rational function approximation based on the vector fitting technique. The antenna provides almost omnidirectional patterns, relatively flat gain, and high radiation efficiency over the entire UWB frequency excluding the rejected bands. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:646–654, 2014
Miniaturized resonant structure for wireless power transfer system based on high‐Q bulk acoustic resonator
Authors: Turalchuk Pavel , Vendik Orest , Vendik Irina , Kholodnyak Dmitry , Song Keum‐Su , Kim Ki Young
Published: January 2014

A novel high‐Q resonant structure comprising the bulk acoustic resonator (BAR) and inductive loop is proposed to be used for wireless power transmission system. The proposed resonant structure operating at MHz frequency range has significantly miniature size in relation to the electrical wavelength (<λ/100) that could be attractive in the field of biology and medicine applications. The efficiency of the wireless power transfer system consisting of ordinary transmitting loop and proposed resonant structure with diameter of 6 mm based on high‐Q BAR has been estimated as higher than 60% at the distance 10 mm. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:531–535, 2014
A low‐power RF receiver for digital TV DVB‐SH
Authors: García‐Vázquez Hugo , Khemchandani Sunil L. , del Pino Javier
Published: January 2014

This article describes a low‐power RF front‐end for digital video broadcasting–satellite services to handhelds (2.17–2.2 GHz) implemented in UMC CMOS 90‐nm process. This receiver includes a resistive feedback low‐noise amplifier and a double‐balanced Gilbert mixer. Measurements show a conversion gain of 24.1 dB, a 3‐dB noise figure, an input return loss of −11.9 dB, and an output compression point of −2.2 dBm. This combination draws 12.4 mW from a 1.2 V supply. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:528–531, 2014
A compact quad‐band band‐pass filter using novel stub‐loaded SIR structure
Authors: Wei Feng , Huang Qiu Lin , Li Wen‐Tao , Shi Xiao‐Wei
Published: January 2014

A compact quad‐band band‐pass filter (BPF) based on a novel stub‐loaded step‐impedance resonator (SL‐SIR) is analyzed and designed in this article. The proposed SL‐SIR, which is found to have the advantages of introducing four narrow passbands and providing more degrees of freedom to adjust the resonant frequencies, is investigated by using even/odd mode analysis. A prototype of a quad‐band BPF centerd at 1.5, 2.5, 3.5, and 5.2 GHz is designed and fabricated. The simulated and measured results are in good agreement with each other. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:538–542, 2014
Optimization of metamaterial structures for terahertz and microwave sensor applications
Authors: Basiri Raheleh , Abiri Habibollah , Yahaghi Alireza
Published: January 2014

In this work, metamaterials are adapted for optimal design of filters with specific characteristics that are useful for sensor applications. The random hill climbing optimization method is used to find optimal structures. Periodic method of moments is applied to calculate the fitness functions of the resulted structures from random hill climbing (RHC) optimizer. One of the optimum structures is fabricated and the measured results are compared with PMOM outputs. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:636–642, 2014
Empirical equations for the resonant frequency of CPW‐FED modified T‐shaped antenna
Authors: Ooi Pei Cheng , Lok Wei Yii
Published: January 2014

Two empirical equations to predict the resonant frequency of the coplanar‐waveguide‐fed modified T‐shaped antenna are proposed. The equations predict resonant frequencies with a maximum error of 3.42%. The least square method has been used to form the equations based on measured data. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:597–600, 2014
Graphene microwave absorber: Transparent, lightweight, flexible, and cost‐effective
Authors: Barbosa Gelza M. , Mosso Marbey M. , Vilani Cecilia , Larrudé Dunieskys R. G. , Romani Eric C. , Junior Fernando L. F.
Published: January 2014

This article presents the graphene as microwave absorber using polyurethane as substrate. The samples were characterized with Raman spectrometer, optical microscope, and vectorial network analyser. The results show a chemical vapor deposition‐grown graphene‐based device that can be used as microwave absorber for its unique characteristics of flexibility, transparency, light‐weight, cost‐effectiveness, and RF shielding. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:560–563, 2014
Forward‐backward method with a spectral acceleration algorithm for capacitance extraction of planar structures on a single‐layered medium
Authors: Pakasiri Chatrpol , Torrungrueng Danai
Published: January 2014

Acceleration of the capacitance extraction of planar structures on a single‐layered medium is reported in this article, using the forward‐backward (FB) method with a spectral acceleration (SA) algorithm. The conventional spectral‐layered medium Green's function is modified appropriately so that it can be effectively incorporated into this method. The SA algorithm substantially speeds up the computational time involving in performing matrix‐vector multiplications in the iterative method of moments (MM). However, the memory requirement for the SA algorithm is comparable to that of the FB method. The computational complexity and the memory requirement are shown to be O(N) for large capacitance extraction problems, where N is the total number of unknowns in the MM for increasing one of the surface dimensions of planar structures and fixed neighborhood distance. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:694–700, 2014
The natural resonant singularity expansion method (SEM) poles for a dielectric sphere in various environments
Authors: Mei Zicong , Lee Woojin , Sarkar Tapan K. , Salazar‐Palma Magdalena
Published: January 2014

When one computes the natural resonant singularity expansion method (SEM) poles for a dielectric sphere composed of different materials, one is surprised to observe that these SEM poles do change too much with corresponding changes in the value of the permittivity and permeability. This article provides an analytical solution as to why it is so. The Mie's series is applied to solve for the resonant frequencies of a dielectric sphere composed of different materials and embedded in various dielectric materials. The variations in the resonant frequencies related to the poles are tabulated along with the material parameters to illustrate the nature of the variation. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:690–694, 2014
A compact dual‐band bandpass filter with high design flexibility using fully isolated coupling paths
Authors: Li Y. , Wang C. , Kim N.Y.
Published: January 2014

A second‐order dual‐band bandpass filter using two outer folding open‐loop resonators and two embedded anchor‐shaped stepped impedance resonators is presented in this letter. The proposed scheme provides sufficient isolation between the two specific passbands, thus each passband can be individually turned. Electric couplings are adopted among the four resonators. By adjusting the spacing of resonators, the electric coupling of two different coupling feeding paths can be independently controlled, which allows flexible control of each bandwidth. The embedded structure which is introduced can further miniaturize the dimensions of the overall structure. In addition, the proposed filter has three transmission zeros at each passband, which exhibit high skirt selectivity. Good agreement between the simulated and measured results validates the correctness of the proposed design approach and shows that the two central frequencies of the fabricated filter are located at 2.5 and 5.1 GHz as desired, with 3 dB fractional bandwidths of 13.8 and 13.6%, respectively. The measured return losses are greater than 18.5 dB, while insertion losses are less than 0.9 dB in each of the two passbands. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:642–646, 2014
Cancer comortality patterns in schizophrenia and psychotic disorders: a new methodological approach for unique databases
Authors: Ajdacic‐Gross Vladeta , Tschopp Alois , Bopp Matthias , Gutzwiller Felix , Rössler Wulf
Published: January 2014

The aim of this study was to determine the pattern of cancer comortality in deaths registered with schizophrenia and psychotic disorders. It focused on the question of whether the proportions of different types of cancer diverge when they are co‐registered with schizophrenia/psychotic disorders or with other causes of death in mortality statistics. We developed an analysis approach applicable to common mortality statistics data when no linkage with morbidity databases or other registers is possible. The analysis covered Swiss mortality data from a 39‐year period (1969 − 2007) and was confined to the most frequent cancers. We applied a two‐step case‐control analysis with bootstrapping (1000 repetitions). The cases were defined by the cancer‐schizophrenia registrations for each specific cancer, whereas the controls were matched from the remaining cases (matching criteria: sex, age, region, subperiod). Cancers with deviant standardized mortality ratios (SMRs) included stomach cancer (1.6; 2.2 after reweighting), lung cancer (0.8; 0.5 after reweighting) and breast cancer (1.6; 1.5 after reweighting). The comortality pattern of cancers in schizophrenia and psychotic disorders diverges from the pattern found in other co‐registered causes of death. The relatively low frequency of lung cancers is particularly paradoxical in view of the smoking habits of schizophrenia patients. Copyright © 2014 John Wiley & Sons, Ltd.
In vivo tumour extracellular pH monitoring using electron paramagnetic resonance: the effect of X‐ray irradiation
Authors: Goodwin Jonathan , Yachi Katsuya , Nagane Masaki , Yasui Hironobu , Miyake Yusuke , Inanami Osamu , Bobko Andrey A. , Khramtsov Valery V. , Hirata Hiroshi
Published: January 2014

The in vivo quantification of extracellular pH (pHe) in tumours may provide a useful biomarker for tumour cell metabolism. In this study, we assessed the viability of continuous‐wave electron paramagnetic resonance (CW‐EPR) spectroscopy with a pH‐sensitive nitroxide for the measurement of extracellular tumour pH in a mouse model. CW‐EPR spectroscopy (750 MHz) of C3H HeJ mice hind leg squamous cell tumour was performed after intravenous tail vein injection of pH‐sensitive nitroxide (R‐SG, 2‐(4‐((2‐(4‐amino‐4‐carboxybutanamido)‐3‐(carboxymethylamino)‐3‐oxoproylthio)methyl)phenyl)‐4‐pyrrolidino‐2,5,5‐triethyl‐2,5‐dihydro‐1Н‐imidazol‐1‐oxyl) during stages of normal tumour growth and in response to a single 10‐Gy dose of X‐ray irradiation. An inverse relationship was observed between tumour volume and pHe value, whereby, during normal tumour growth, a constant reduction in pHe was observed. This relationship was disrupted by X‐ray irradiation and, from 2–3 days post‐exposure, a transitory increase in pHe was observed. In this study, we demonstrated the viability of CW‐EPR spectroscopy using R‐SG nitroxide to obtain high‐sensitivity pH measurements in a mouse tumour model with an accuracy of <0.1 pH units. In addition, the measured changes in pHe in response to X‐ray irradiation suggest that this may offer a useful method for the assessment of the physiological change in response to existing and novel cancer therapies. Copyright © 2014 John Wiley & Sons, Ltd.
A projected Newton algorithm for the dual convex program of elastoplasticity
Authors: Lotfian Z. , Sivaselvan M.V.
Published: January 2014

In this paper, we study a dual optimization problem that arises when taking a mathematical programming approach to incremental state update in nonlinear problems. The mathematical programming approach stems from energy‐based descriptions of constitutive models. We describe a projected Newton algorithm to solve the dual optimization problem. This algorithm requires solution of an unconstrained optimization problem at the integration point level, rather than a constrained one as carried out by classical return‐mapping schemes. Especially, implementation of multi‐surface plasticity models is no more involved than that of single‐surface models. We explore characteristics and performance of the projected Newton algorithm through numerical examples. Insights gained from such a further exploration of mathematical programming algorithms are likely to aid in development of successive convex programming approaches to geometric nonlinear and other non‐convex problems such as non‐associated flow models. Copyright © 2014 John Wiley & Sons, Ltd.
Modeling of flow‐induced sound in porous materials
Authors: Beck S. C. , Langer S.
Published: January 2014

The impact of flow on a structure plays a crucial part when considering structural behavior, for example, in aviation. As structural vibrations (also denominated as structural sound) propagate within a structure, sound radiation is a likely consequence. To reduce the emission of noise, the use of poroelastic material is investigated. The approach consists in applying a poroelastic layer on the surface submitted to flow, as such utilizing the damping properties of poroelastic material.

To predict flow‐induced sound, a computational model has been developed to account for (1) flow‐induced sound immission into a structure; (2) sound propagation; and (3) possible resulting sound radiation. Consistent formulation of the interactions between the components—that is, flow, poroelastic material, elastic structure, and acoustic fluid—allows to apply different simulation techniques for each component and thus to exploit each method's advantages. The key aspect of this work is the formulation of the interface conditions to couple flow with poroelastic material. The proposed and implemented coupling conditions are studied. The given example shows a possible application and demonstrates the effectiveness of poroelastic material to reduce flow‐induced sound emission. Copyright © 2014 John Wiley & Sons, Ltd.
On best‐fit corotated frames for 3D continuum finite elements
Authors: Mostafa M. , Sivaselvan M.V.
Published: January 2014

We discuss a strategy to construct corotated frames for three‐dimensional continuum finite elements by minimizing deformations within the frame. We find that irrespective of the type of element and the number of nodes, using a quaternion parametrization of rotations, this minimization is naturally stated as computing the smallest eigenvalue of a 4 × 4 matrix. The simplicity of this smallest eigenvalue plays a crucial role when linearizing the kinematics. Ensuant quaternion algebra, although lengthy, results in remarkably simple formulas for projections that arise in the linearized kinematics. The exact stiffness matrix does not require computation of the second derivative of the rotation function and is also given by a simple formula. As a result, the implementation of this corotational formulation becomes particularly straightforward. Furthermore, in contrast to other results in the literature, the stiffness matrix for elements with translational DOFs is symmetric. For illustration, this corotational formulation is applied to a solid‐shell finite element, and numerical results are presented. Copyright © 2014 John Wiley & Sons, Ltd.
A decoupling two‐grid algorithm for the mixed Stokes‐Darcy model with the Beavers‐Joseph interface condition
Authors: Zuo Liyun , Hou Yanren
Published: January 2014

In this article, a decoupling scheme based on two‐grid finite element for the mixed Stokes‐Darcy problem with the Beavers‐Joseph interface condition is proposed and investigated. With a restriction of a physical parameter α, we derive the numerical stability and error estimates for the scheme. Numerical experiments indicate that such two‐grid based decoupling finite element schemes are feasible and efficient. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1066–1082, 2014
Effect of organoclay on the morphology, mechanical, and thermal properties of polyimide/organoclay nanocomposite foams
Authors: Qi Kailiang , Zhang Guangcheng
Published: January 2014

A series of polyimide (PI)/organoclay nanocomposite foams containing different contents of organoclay were prepared by the monomer in situ intercalative polymerization. The effect of organoclay on the chemical structure, morphology, mechanical, and thermal properties of the nanocomposite foams was studied. Fourier transform infrared spectra showed that the hydrogen bonds between organoclay and the polymer matrix were formed. X‐ray diffraction and transmission electron microscope results indicated that the organoclay were well dispersed in the PI matrix. The compressive strength and tensile strength of the nanocomposite foams enhanced significantly, especially for the nanocomposite foam containing 4 wt% organoclay, increasing by 15% and 9%, respectively, compared with these of the neat PI foam, and the presence of the organoclay in the PI foam improved apparently the cellular structure of the nanocomposite foams. Besides, thermogravimetric analysis revealed that the addition of organoclay improved the thermal stability of the nanocomposite foams strongly, and dynamic mechanical analysis indicated that the incorporation of organoclay significantly influenced the storage modulus of the nanocomposite foams. POLYM. COMPOS., 35:2311–2317, 2014. © 2014 Society of Plastics Engineers
Maternal body composition and birth weight
Authors: Connor Clare O' , O' Higgins Amy , Segurado Ricardo , Turner Michael J. , Stuart Bernard , Kennelly Máireád M.
Published: January 2014

What's already known about this topic?

Birth weight (BW) prediction is an important part of obstetric management.

It is a key determinant of perinatal outcome with poor outcomes resulting from delivering macrosomic neonates or growth‐restricted neonates.

Maternal obesity, assessed by BMI, has been associated with an increased risk of fetal macrosomia, neonatal adiposity and metabolic syndrome.

There is a paucity of data in the literature on maternal body composition and its relationship to BW.

What does this study add?

First trimester maternal body composition was assessed accurately and objectively by bioelectrical impedance analysis and correlated to BW.

We accurately identify which maternal body composition parameters including visceral fat and waist circumference independently influence BW.

We also explore customised centiles and population based centiles at birth.

Potentially, this study may help to identify a modifiable risk factor to reduce the incidence of macrosomia and neonatal adiposity.
Efficiency loss prevention in monolithically integrated thin film solar cells by improved front contact
Authors: van Deelen Joop , Barink Marco , Klerk Lennaert , Voorthuijzen Pim , Hovestad Arjan
Published: January 2014

For thin film solar cells, there is a large gap between the record efficiencies and panel power output. It was found that for a “typical industrial” CIGS cell efficiency of 15.5%, the efficiency drops to 11.7% when it is operating under the circumstances of a monolithically integrated solar panel. Part of this gap is due to limited conductivity and transmittance of the front contact. By application of a metallic grid, the conductivity can be improved by over two order of magnitude at a transmittance loss of only a few percent as was shown experimentally. In addition, modeling was used to quantify the impact of such approach on the power output of monolithically integrated solar panels. This model includes optical and resistive losses, as well as related losses caused by the inhomogeneity of the operating voltage over the surface. Both power output and the different types of losses are mapped out for various cell configurations. Optimization of transparent conductive oxide resistance, cell length, finger width, and finger spacing of grids was performed and led to an efficiency improvement from 11.7% to 13.8% when the front contact is upgraded with a metallic grid consisting of 20 µm wide parallel fingers positioned perpendicular to the interconnect. Further optimization for a wide variety of cell and grid configurations show that for a technically more feasible size of 100 µm wide fingers, the calculated efficiency is still 13.5%. Finally, the power output is mapped out for a large number of configurations as to create an overview and insight in the interdependencies of cell configuration and finger dimensions. Copyright © 2014 John Wiley & Sons, Ltd.
AFRICAN AMERICAN SCHOOL PSYCHOLOGISTS’ PERCEPTIONS OF THE OPPORTUNITIES AND CHALLENGES OF PRACTICING IN SOUTHEASTERN UNITED STATES
Authors: Truscott Stephen D. , Proctor Sherrie L. , Albritton Kizzy , Matthews Yanique , Daniel Kirnel
Published: January 2014

Rapid demographic shifts in the United States’ school‐aged population require school psychology to research and address issues related to limited racial/ethnic diversity in the profession. This qualitative study explored the work‐related experiences and perceptions of 30 African American School Psychologists who practiced in the Southeastern United States. Findings revealed that African American School Psychologists perceive their ability to help children, advocate for children of color, and provide positive representations of people of color as opportunities. They perceive racial bias, including racial microaggressions, as a primary challenge in their careers. Based on these results, recommendations for research, training, and practice are provided.
Associations between accurate prognostic understanding and end‐of‐life care preferences and its correlates among Taiwanese terminally ill cancer patients surveyed in 2011–2012
Authors: Tang Siew Tzuh , Liu Tsang‐Wu , Chow Jyh‐Ming , Chiu Chang‐Fang , Hsieh Ruey‐Kuen , Chen Chen H. , Liu Li Ni , Feng Wei‐Lien
Published: January 2014

Objective

Adequate knowledge of prognosis is a prerequisite for planning appropriate end‐of‐life (EOL) care. However, questions remain about whether the association between prognostic understanding and EOL‐care intensity reflects terminally ill cancer patients' preferences for EOL care. This study investigated the associations between accurate prognostic understanding and EOL‐care preferences, and identified correlates of accurate prognostic understanding.

Methods

A cross‐sectional survey of 2452 terminally ill cancer patients from 23 hospitals throughout Taiwan.

Results

Nearly half the participants (49.80%) accurately understood their prognosis. These patients were significantly more likely to prefer comfort‐oriented care as their goal for EOL care, but less likely to prefer life‐prolonging treatments. Accurately understanding prognosis decreased the likelihood of preferring intensive care unit care, cardiac pulmonary resuscitation, cardiac massage, intubation, and mechanical ventilation support, but increased preference for hospice care. Participants were significantly more likely to accurately understand their prognosis if they were male, younger, better educated, with a stronger preference for physicians to disclose their prognosis to them, and receiving care at a hospital accredited as a medical center and in northwest Taiwan. The likelihood of accurate prognostic understanding was lower for patients recently (≤12 months) diagnosed with cancers with better prognosis and hematologic malignancies than for lung cancer patients.

Conclusions

Accurately understanding prognosis is associated with fewer preferences for life‐sustaining treatments and is correlated with both patient and institutional characteristics. Interventions should be developed to improve accurate prognostic understanding, thus facilitating informed EOL‐care decisions that may limit the use of aggressive interventions. Copyright © 2014 John Wiley & Sons, Ltd.
Non‐Invasive Geophysical Investigation and Thermodynamic Analysis of a Palsa in Lapland, Northwest Finland
Authors: Kohout Tomas , Bućko Michał S. , Rasmus Kai , Leppäranta Matti , Matero Ilkka
Published: January 2014

Non‐invasive geophysical prospecting and a thermodynamic model were used to examine the structure, depth and lateral extent of the frozen core of a palsa near Lake Peerajärvi in northwest Finland. A simple thermodynamic model verified that the current climatic conditions in the study area allow sustainable palsa development. A ground penetrating radar (GPR) survey of the palsa under both winter and summer conditions revealed its internal structure and the size of its frozen core. GPR imaging in summer detected the upper peat/core boundary, and imaging in winter detected a deep reflector that probably represents the lower core boundary. This indicates that only a combined summer and winter GPR survey completely reveals the lateral and vertical extent of the frozen core of the palsa. The core underlies the active layer at a depth of ~ 0.6 m and extends to about 4 m depth. Its lateral extent is ~ 15 m x ~ 30 m. The presence of the frozen core could also be traced as minima in surface temperature and ground conductivity measurements. These field methods and thermodynamic models can be utilised in studies of climate impact on Arctic wetlands. Copyright © 2014 John Wiley & Sons, Ltd.
Mapping orphan proteases by proteomics: Meprin metalloproteases deciphered as potential therapeutic targets
Authors: Becker‐Pauly Christoph , Broder Claudia , Prox Johannes , Koudelka Tomas , Tholey Andreas
Published: January 2014

The protease web is a synonym for highly regulated molecular networks comprising enzymes, substrates, inhibitors, and other regulatory proteins. Latest high‐throughput methods provided huge data sets, revealing an amazing complexity of proteolytic systems important for health and disease. Based on our previous studies, we discuss major problems and questions that have to be solved to gain precise insight into the regulation of the protease web and its impact on pathophysiological conditions. The goal is a combination of different proteomic approaches that help to investigate specific protease function at a glance. Exemplarily, the characterization of the metalloproteases meprin α and meprin β by proteomic identification of cleavage sites and terminal amine isotopic labeling of substrates demonstrates the power of MS‐based techniques. Meprins are rather orphan proteases and could not be assigned to precise biological functions until recently. Proteomics helped to identify meprin α and meprin β being important for collagen assembly and deposition in skin, which makes them potential therapeutic targets in fibrotic conditions. Additionally, identification of the cleavage site specificity provides the basis for the development of activity‐based probes and small compound inhibitors, important for the regulation of meprin activity and subsequent treatment of associated diseases.