bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of cathodic electrochemical potential of Ti‐6Al‐4V on cell viability: voltage threshold and time dependence
Authors: Sivan Shiril , Kaul Shereen , Gilbert Jeremy L.
Published: July 2013

The biocompatibility of metallic biomaterials is dependent on the redox state of the surface and its effect on cellular redox equilibrium. When metallic biomaterials experience mechanically assisted corrosion such as fretting, there is a drop in the voltage of its surface. Studies have demonstrated that cell viability is significantly degraded by sustained cathodic excursion in voltage of metallic biomaterials below a critical potential between −300 and −600 mV on commercially pure titanium. Cells cultured at above −300 mV showed little loss in viability whereas cells cultured on −600 mV Ti were almost 100% killed at 24 h. The goal of this study is to concisely define the voltage threshold and time‐dependence of the cell killing effect seen on titanium surfaces. MC3T3 cells were cultured on electrochemically controlled Ti‐6Al‐4V surfaces at voltages ranging from −300 to −1000 mV for time periods ranging from 1 to 24 h. Cell viability and morphology was monitored with live‐dead assay and scanning electron microscopy. Cell viability decreased from −300 to −400 mV and exhibited time‐dependence where the more cathodic the potential, the faster the drop‐off of viability. Hundred percent cell killing took as little as 4 h at −1000 mV and required 24 h at −400 mV. Sustained net cathodic currents with densities as low as 0.1 μA/cm2 are observed during cell killing. This work shows reduction reactions are an important element of cellular viability in a time and potential dependent way and may explain why mechanically assisted corrosion reactions may lead to increased cell killing in metallic implants. Note: All voltages are versus Ag/AgCl © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1489–1497, 2013.
Live unilateral twin ectopic pregnancy in a fallopian tube remnant after previous ipsilateral salpingectomy
Authors: Longoria Teresa C. , Stephenson Megan L. , Speir Vinita J.
Published: July 2013

Ectopic pregnancy remains an important cause of morbidity and mortality in women of childbearing age. We report a case of a unilateral twin ectopic pregnancy in a fallopian tube remnant after previous ipsilateral salpingectomy. The pregnancy was conceived spontaneously and included two live gestations. Although the presentation of this ectopic pregnancy was unique, the patient's risk factors were not. As an example of the type of patient who would benefit from ultrasound screening for ectopic pregnancy, our patient renews the debate around this controversial issue. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:169–171, 2014
Acute suppurative thyroiditis following fine‐needle aspiration biopsy in an immunocompetent patient
Authors: Ünlütürk Uğur , Ceyhan Koray , Çorapçıoğlu Demet
Published: July 2013

The thyroid gland is remarkably resistant to infectious agents owing to several protective mechanisms. Acute suppurative thyroiditis after fine‐needle aspiration (FNA) in an immunocompetent patient is very rare. We report the case of a 50‐year‐old immunocompetent male patient who presented with painful cervical swelling, fever, and chills after an FNA of the thyroid. His physical and laboratory examination suggested an acute suppurative thyroiditis. Repeat FNA results were consistent with thyroid abscess. Physicians should be aware of the probability of acute bacterial thyroiditis after FNA. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:215–218, 2014
The effect of volcanic eruptions on global precipitation
Authors: Iles Carley E. , Hegerl Gabriele C. , Schurer Andrew P. , Zhang Xuebin
Published: July 2013

We examine robust features of the global precipitation response to 18 large low‐latitude volcanic eruptions using an ensemble of last millennium simulations from the climate model HadCM3. We then test whether these features can be detected in observational land precipitation data following five twentieth century eruptions. The millennium simulations show a significant reduction in global mean precipitation following eruptions, in agreement with previous studies. Further, we find that the response over ocean remains significant for around 5 years and matches the timescale of the near‐surface air temperature response. In contrast, the land precipitation response remains significant for 3 years and reacts faster than land temperature, correlating with aerosol optical depth and a reduction in land‐ocean temperature contrast. In the tropics, areas experiencing posteruption drying coincide well with climatologically wet regions, while dry regions get wetter on average, but there changes are spatially heterogeneous. This pattern is of opposite sign to, but physically consistent with, projections under global warming. A significant reduction in global mean and wet tropical land regions precipitation is also found in response to twentieth century eruptions in both the observations and model masked to replicate observational coverage, although this is not significant for the observed wet regions response in boreal summer. In boreal winter, the magnitude of this global response is significantly underestimated by the model; the discrepancy originating from the wet tropical regions although removing the influence of ENSO improves agreement. The modeled precipitation response is detectable in the observations in boreal winter but marginal in summer.
Analytical and semipreparative separation of 25 (R/S)‐spirostanol saponin diastereomers using supercritical fluid chromatography
Authors: Zhao Yang , McCauley John , Pang Xu , Kang Liping , Yu Heshui , Zhang Jie , Xiong Chengqi , Chen Rui , Ma Baiping
Published: July 2013

Spirostanol saponins are a class of steroidal saponins with many pharmacological activities. The structural complexity of the spirostanol saponins presents a daunting challenge in separating their 25 R/S diastereomers. Using two CHIRALPAK IC columns coupled in series, six 25 (R/S)‐spirostanol saponin diastereomers from the Trigonella foenum‐graecum L. seed were successfully separated using supercritical fluid chromatography (SFC) for the first time. In addition, three 25 (R/S)‐spirostanol saponin diastereomers were isolated into their respective individual isomers. The structures of the isolated isomers were unambiguously confirmed by NMR analysis. The SFC method development strategy and its associated underlying principles presented in this paper are generally applicable. SFC is a viable addition to the natural product research toolbox, especially for stereoselective analysis and purification.
Absorbance detector based on a deep UV light emitting diode for narrow‐column HPLC
Authors: Bui Duy Anh , Bomastyk Benjamin , Hauser Peter C.
Published: July 2013

A detector for miniaturized HPLC based on deep UV emitting diodes and UV photodiodes was constructed. The measurement is accomplished by the transverse passage of the radiation from the light‐emitting diode (LED) through fused‐silica tubing with an internal diameter of 250 μm. The optical cell allows flexible alignment of the LED, tubing, and photodiode for optimization of the light throughput and has an aperture to block stray light. A beam splitter was employed to direct part of the emitted light to a reference photodiode and the Lambert–Beer law was emulated with a log‐ratio amplifier circuitry. The detector was tested with two LEDs with emission bands at 280 and 255 nm and showed noise levels as low as 0.25 and 0.22 mAU, respectively. The photometric device was employed successfully in separations using a column of 1 mm inner diameter in isocratic as well as gradient elution. Good linearities over three orders of magnitude in concentration were achieved, and the precision of the measurements was better than 1% in all cases. Detection down to the low micromolar range was possible.
Synthesis of Polypeptide Block Copolymer Hybrids by the Combination of N‐Carboxyanhydride Polymerization and RAFT
Authors: Jacobs Jaco , Gathergood Nicholas , Heise Andreas
Published: July 2013

The synthesis of hybrid bioconjugates via the ring‐opening polymerization (ROP) of N‐carboxyanhydrides (NCAs) using a synthetic macroinitiator is described. Poly(n‐butyl acrylate), polystyrene, and poly(N‐isopropyl acrylamide) are synthesized (polydisperity index, Đ < 1.1) using reversible addition–fragmentation chain transfer (RAFT) as the synthetic tool. A phthalimidomethyl trithiocarbonate RAFT chain transfer agent is used to prepare well‐defined, end‐functional polymers, which after deprotection result in amine terminal macroinitiators. The subsequent initiating systems could successfully be chain extended with ε‐benzyloxycarbonyl‐l‐lysine or γ‐benzyl‐l‐glutamate as the NCAs to produce a library of polymer–polypeptide conjugates. In doing so, a novel procedure for directly synthesizing bioconjugates via a non‐modular route without the need for excessive purification and isolation steps is described.

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Characterization of mineral phosphate solubilization traits from a barley rhizosphere soil functional metagenome
Authors: Chhabra Sagar , Brazil Dina , Morrissey John , Burke James I. , O'Gara Fergal , N. Dowling David
Published: July 2013

Mineral phosphate solubilization (MPS) microorganisms are important for their provision of orthophosphate anions for plant growth promotion activity in soil. In this study, we applied a functional metagenomic approach to identify this trait directly from the microbiome in barley rhizosphere soil that had not received P fertilizer over a 15‐year period. A fosmid system was used to clone the metagenome of which 18,000 clones (~666 Mb of DNA) was screened for MPS. Functional assays and High Performance Liquid Chromatography analysis recognized gluconic acid production and MPS activity in the range 24.8–77.1 mmol/L and 27.6–38.16 μg/mL, respectively, when screened in an Escherichia coli host (at frequency of one MPS‐positive clone hit per 114 Mb DNA tested). The MPS clones (with average insert size of ~37 kb) were analysed by 454 Roche sequencing and annotated. A number of genes/operons with homology to Phosphorous (P) uptake, regulatory and solubilization mechanisms were identified, linking the MPS function to the uncultivated microbiome present in barley rhizosphere soil.
Tunable Band‐Pass Filters Based on Varactor‐Loaded Complementary Split‐Ring Resonators on Half‐Mode Substrate Integrated Waveguide
Authors: Sam Somarith , Lim Sungjoon
Published: July 2013

Miniaturized band‐pass filters (BPFs) using backward wave propagation in the left‐handed (LH) band are proposed in this article. A half‐mode substrate integrated waveguide (HMSIW), complementary split‐ring resonators (CSRRs), and varactors are embedded on the same planar platform to implement the resonant‐type approach of metamaterial transmission line and tuning capability. The tuning of the passband frequency is generated by simple and single direct current (DC) voltages from 0 to 36 V, which are applied to each varactor on CSRRs. Different capacitance values and resonant frequencies are produced while maintaining a nearly constant absolute bandwidth and quality factor. About 6.5% tunability and 11.30% of 3‐dB fractional bandwidth is achieved around 2.30 GHz. The new electrically tunable BPFs are verified by a good agreement between the simulated and measured results. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2458–2460, 2013
Microwave Tunable Notch Filter Based on Liquid Crystal Using Spiral Spurline Technology
Authors: Torrecilla Javier , Avila‐Navarro E. , Marcos Carlos , Urruchi Virginia , Sanchez‐Pena Jose M. , Arias Julia , Sanchez‐Lopez Maria M.
Published: July 2013

In this article, the design, fabrication, and characterization of a tunable microwave notch filter based on liquid crystal (LC) using inverted‐microstrip technology is presented. A spiral spurline structure is used because of its good performance as a single‐resonator notch filter. Based on the LC dielectric anisotropy, a voltage‐controlled rejection frequency of the filter is achieved, ranging from 3.40 to 3.75 GHz, which means that the tuning range relative to the central rejection frequency is about 10%. At the same time, this device exhibits negative group delay around the rejection frequency and the measured values throughout the tuning frequency range are presented. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2420–2423, 2013
A Regulated 3.1–10.6 GHz Linear Dual‐Tuning Differential Ring Oscillator For UWB Applications
Authors: Lu Li , Li Changzhi , Lin Jenshan
Published: July 2013

A regulated linear dual‐tuning differential ring oscillator has been designed and fabricated in UMC 0.13 μm CMOS process for ultra‐wideband applications. Measurement results demonstrated the large tuning range, high tuning linearity, fast band switching, low supply sensitivity, and acceptable phase noise. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2384–2389, 2013
A Wideband Frequency Synthesizer with High Frequency Resolution
Authors: Tian Ling , Liu Jiaqi
Published: July 2013

This article presents the design and implementation of a wideband frequency synthesizer which uses a direct digital synthesis as a fractional divider in the phase‐locked loop. The frequency resolution is 7.1 × 10−5 Hz. A phase‐domain model of this synthesizer is analyzed and simulated. A formula of output phase noise is derived. The output phase noise of synthesizer is −124 dBc/Hz (10 kHz offset) at the frequency of 1 GHz. The frequency synthesizer model has been designed with advantages of wide bandwidth, low phase noise, high‐frequency resolution, low spurious, high frequency stability, and simple structure. With frequency multiplier and divider module, the frequency band of synthesizer can be extended from 250 MHz to 8 GHz. The module is suitable for communication instrument. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2454–2457, 2013
Development of 5.5‐GHz Band Pass Filter in All Silicon Multilayer Substrate with Air Dielectric
Authors: Seek Cho Young , Franklin Rhonda R.
Published: July 2013

A compact 5.5‐GHz band pass filter (BPF) with 12.7% 3‐dB bandwidth is developed in an all silicon multilayer substrate with air dielectric incorporated for WiMax applications. The topology of the BPF is a capacitively coupled fifth‐order Chebyshev BPF. Its volume is 9.3 × 8.5 × 0.6 mm3. Two design aspects—air dielectric and through silicon via (TSV) technology integration—play an essential role in the BPF implementation. The spiral inductor with an integrated air dielectric has quality factor and self‐resonant frequency improvement of 112 and 41%, respectively. The TSVs in the BPF design enables the implementation of two‐layer inductors with a low value of inductance. The volume of TSV in the two‐layer inductor is 75 × 75 × 200 μm3 and its inductance is 0.15 nH at 5 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2340–2345, 2013
Wide‐Locking Range Dual‐Band Injection‐Locked Frequency Divider
Authors: Jang Sheng‐Lyang , Wu Zhi‐Hong , Hsue Ching‐Wen , Teng Heng‐Fa
Published: July 2013

A wide locking range divide‐by‐2 CMOS LC‐tank injection locked frequency divider is proposed and is realized with two mixers in series and a cross‐coupled oscillator with dual‐resonance LC resonator to provide large output voltage swings at high‐ and low‐frequency bands. The dual‐band function can be obtained without switching. Measurement results show that at the supply voltage of 0.8 V, the free‐running frequency is from 3.571 to 3.974 GHz for the high‐frequency band and from 2.278 to 2.349 GHz for the low‐frequency band. At Vtune = 1.2 V, an external injected signal power of 0 dBm provides a low‐band divide‐by‐2 locking range (57.7%) from 2.87 to 5.2 GHz and a high‐band locking range (25.7%) from 7.1 to 9.2 GHz. At Vtune = 0 V an external injected signal power of 0 dBm provides a high‐band locking range (46.5%) from 5.6 to 9 GHz and a low‐band locking range (25.0%) from 2.8 to 3.6 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2333–2337, 2013
Coplanar Waveguide Reconfigurable Bandpass Filter Based on A Varactor Loaded Colinear Resonator
Authors: Wang Zhengpeng P. , Hall Peter S. , Kelly James , Gardner Peter
Published: July 2013

This article reports a novel coplanar waveguide varactor‐tuned bandpass filter based on a colinear resonator. The equivalent circuit of the new filter is analyzed. The passband of the filter can be tuned from 0.68 to 1.37 GHz by varying the capacitance of the varactor diode. The insertion loss of this filter changes from 0.9 to 1.3 dB across the tuning range. The 3‐dB bandwidth changes from 141 to 153 MHz as the filter is tuned from 0.68 to 1.18 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2389–2393, 2013
Bandwidth Enhancement Using Z‐Shaped Defected Ground Structure for a Microstrip Antenna
Authors: Kandwal Abhishek , Sharma Rakesh , Kumar Khah Sunil
Published: July 2013

A novel design of a circular patch antenna having Z‐shaped defected ground structure is presented in this communication. The antenna is designed for X‐band applications. A wideband is obtained in the X‐band frequency range 8–12 GHz. The return loss and input impedance is measured experimentally and compared with the simulated results. Parameters like impedance bandwidth, voltage standing wave ratio, and antenna gain are calculated and discussed. Impedance bandwidth of about 1.2 GHz is obtained with a gain of 8.7 dBi and side lobe level of −20.1 dB. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2251–2254, 2013
Size Reduction of Series‐Fed Two Dipole Array Antenna Using Top‐Loaded Elements
Authors: Yeo Junho , Lee Jong‐Ig
Published: July 2013

In this article, a method for size reduction of a series‐fed two dipole array (STDA) antenna using top‐loaded elements is presented. In order to reduce the lateral size of a conventional STDA antenna, rectangular patch‐shaped top loading is used for the two dipole elements of the STDA antenna and a grooved ground plane is used by adding a patch at both ends of the ground plane. The effects of varying the length and width of the rectangular patch‐shaped top loading on the antenna performances, such as the input reflection coefficient and the realized gain, are investigated. A proposed size‐reduced STDA antenna covering a frequency band ranging from 1.7 GHz to 2.7 GHz with a gain > 5 dBi is designed and fabricated on an FR4 substrate. The total width of the fabricated prototype of the proposed antenna is reduced by approximately 14.3% compared to the conventional STDA antenna, and it presents a 48.7% bandwidth in the range of 1.68–2.76 GHz and a stable gain of 5.6–6.0 dBi with minimal degradation. Moreover, a front‐to‐back ratio is improved by about 0.7–4.8 dB. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2288–2293, 2013
Design and Optimization of New Compact Tunable 2.4‐GHz Band Pass Filter Using Coupled λ/2 Microstrip Open‐Loop Resonators and Mems‐Switch Technique
Authors: Boutejdar Ahmed , Omar Abbas , Burte Edmund
Published: July 2013

A new compact WLAN‐band pass filters are proposed using a half wavelength microstrip open‐loop and λ/2 microstrip resonators based on direct‐cross coupling method and micro electronic mechanical system (MEMS) technology. The filter is not only compact in size due to the slow‐wave effect, but also has multitransmission zeros at both low and high rejection bands, as well as low insertion loss in the pass band. A demonstration filter has been designed and tested. Simulation results almost agree with the measured results. Some discrepancy between them can still be observed, which can be attributed to the unexpected tolerance of fabrication. Due to the simplicity of the design and its fabrication, it shows that this type of band pass filter has great potential for actual applications in communication and other systems. By applying the MEMS technology, a switchable band pass filter based on the quadruplet filter is able to be designed. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2444–2450, 2013
A Temperature‐Insensitive Relative Humidity Sensor by using Polarization Maintaining Fiber‐Based Sagnac Interferometer
Authors: Wang Jianfeng , Liang Houhui , Dong Xinyong , Jin Yongxing
Published: July 2013

A relative humidity sensor based on two polarization maintaining fibers (PMFs) Sagnac interferometer with temperature compensation is presented by utilizing polyvinyl alcohol (PVA) as the sensitive cladding film. The proposed sensor is created through coating a thin layer of PVA onto a PMF from which a portion of the cladding is etched. PVA‐coated PMF is for air relative humidity measurement and the other section PMF is for temperature compensation. The results show that the dip wavelength of the transmission spectrum shifts with the relative humidity with a high sensitivity of 111.5 pm/%RH. Meanwhile the sensor is insensitive to environmental temperature change with thermal‐dependent coefficient of 7.2 pm/°C. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2305–2307, 2013
Design of a Printed Dipole Array Antenna with Wideband Power Divider and RF Switches
Authors: Huang Jhin‐Fang , Wen Jiun‐Yu , Lai Wen‐Cheng
Published: July 2013

In this article, we use pattern‐diversity technique to combine a RF single‐pole double‐throw (SPDT) switch with an antenna array together in order to reduce the signal distortion caused by multipath fading. In addition, in order to improve the way controlling the SPDT switch by software, a novel circuit structure which will control antenna pattern switching automatically by hardware is also developed. Return loss and radiation patterns are presented and compared with the measured results. Good agreement is achieved between computed and measured results and illustrates the validity of the designed method. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2410–2413, 2013
Wavelength Tuning for LiNbO3 Photonic Sensor to Have Linear Operation Point
Authors: Zhang Jiahong , Chen Fushen , Sun Bao , Li Chengxin
Published: July 2013

A new method to control the bias angle of asymmetric Mach–Zehnder interferometer‐based LiNbO3 photonic sensor for accurate intensive E‐field measurement has been proposed and experimentally demonstrated in this article. By adjusting the wavelength of a tunable laser using a microcontroller unit, the sensors can have a linear operating point while not distort the E‐field under measurement. This method successfully controls such LiNbO3 photonic sensor without distorting the output optical waveform. Linear characteristic of this sensing system with proposed control system has been measured and the correlation coefficient between measured and fitting is 0.999 from 160 to 840 Kv/m. All these prove wavelength tuning is available for photonic sensors to detected and extract E‐field accurately. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2326–2329, 2013
Dual‐Frequency and Dual‐Mode Circular Patch Antennas Based on Epsilon‐Negative Transmission Line
Authors: Hou Quanwen , Tang Hangfei , Liu Yahong , Zhao Xiaopeng
Published: July 2013

Dual‐frequency and dual‐mode circular patch antennas based on epsilon‐negative (ENG) transmission line have been investigated. By input impedance matching, the TM01 mode with omnidirectional radiation pattern and TM11 mode with directional radiation pattern can be excited at two separate frequencies, and then the dual‐frequency and dual‐mode operation is achieved. Compared with the conventional dual‐frequency or dual‐mode patch antennas, the new designed antenna only need one patch and one feed. More important, the omnidirectional mode of proposed antenna can be excited at lower frequency than directional mode, and the frequency ratio of the two modes can be tuned by changing the number of the ENG unit cell. The performances of the proposed antennas are studied numerically and experimentally. The measured results are in good agreement with the simulated ones. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2393–2398, 2013
Erratum: Power Divider with Arbitrary Power Ratio and Arbitrary Ripple Level Using Filter Synthesis Techniques
Authors: Zhang Qingfeng , Caloz Christophe
Published: July 2013

Originally published Microwave Opt Technol Lett 55:1819–1820, 2013; © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2524, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27945 (Original article DOI 10.1002/mop.27722)
The frontal space measurement in euploid and aneuploid pregnancies at 11–13 weeks' gestation
Authors: Yazdi Britta , Riefler Peter , Fischmüller Kristina , Sonek Jiri , Hoopmann Markus , Kagan Karl Oliver
Published: July 2013

Objective

The aim of this study is to evaluate whether the measurement of the frontal space (FS) improves first trimester combined aneuploidy screening.

Methods

We have presented a retrospective study including 2D images of the nuchal translucency measurement of 300 euploid and 133 trisomic fetuses that were seen at the prenatal department at the University of Tuebingen, Germany. For the FS measurement, a mandibulo‐maxillary line (MML) was created by connecting the anterior edge of the mental protuberance and anterior edge of the maxilla. The MML was then extended upwards. A measurement was taken perpendicular from the MML to the skin line over the point of largest excursion of the fetal forehead. After transformation into z‐scores based on the crown rump length, the FS distribution in fetuses with trisomy 21, 18, and 13 was compared with the euploid group by using a student's t‐test.

Results

The mean FS in euploid fetuses was 1.25 mm. In fetuses with trisomy 21, 18, and 13, the mean FS measurements were 2.96, 3.22, and 2.03 mm. In euploid and trisomy 21, 18, and 13 pregnancies, FS measurements were above the 95th centile in 5.3%, 41.1%, 34.3%, and 12.5% of the cases. The mean z‐scores were significantly higher in trisomy 21 and 18.

Conclusion

First trimester FS measurement may improve first trimester combined screening. © 2013 John Wiley & Sons, Ltd.
In vitro activity of novel in silico‐developed antimicrobial peptides against a panel of bacterial pathogens
Authors: Romani A. A. , Baroni M. C. , Taddei S. , Ghidini F. , Sansoni P. , Cavirani S. , Cabassi C. S.
Published: July 2013

Antimicrobial‐peptide‐based therapies could represent a reliable alternative to overcome antibiotic resistance, as they offer potential advantages such as rapid microbicidal activity and multiple activities against a broad spectrum of bacterial pathogens.

Three synthetic antimicrobial peptides (AMPs), AMP72, AMP126, and also AMP2041, designed by using ad hoc screening software developed in house, were synthesized and tested against nine reference strains. The peptides showed a partial β‐sheet structure in 10‐mM phosphate buffer. Low cytolytic activity towards both human cell lines (epithelial, endothelial, and fibroblast) and sheep erythrocytes was observed for all peptides. The antimicrobial activity was dose dependent with a minimum bactericidal concentration (MBC) ranging from 0.17 to 10.12 μM (0.4–18.5 µg/ml) for Gram‐negative and 0.94 to 20.65 μM (1.72‐46.5 µg/ml) for Gram‐positive bacteria. Interestingly, in high‐salt environment, the antibacterial activity was generally maintained for Gram‐negative bacteria. All peptides achieved complete bacterial killing in 20 min or less against Gram‐negative bacteria. A linear time‐dependent membrane permeabilization was observed for the tested peptides at 12.5 µg/ml. In a medium containing Mg2+ and Ca2+, the peptide combination with EDTA restores the antimicrobial activity particularly for AMP2041. Moreover, in combination with anti‐infective agents (quinolones or aminoglycosides) known to bind divalent cation, AMP126 and AMP2041 showed additive activity in comparison with colistin.

Our results suggest the following: (i) there is excellent activity against Gram‐negative bacteria, (ii) there is low cytolytic activity, (iii) the presence of a chelating agent restores the antimicrobial activity in a medium containing Mg2+ and Ca2+, and (iv) the MBC value of the combination AMPs–conventional antibiotics was lower than the MBC of single agents alone. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Multiplicity: discussion points from the Statisticians in the Pharmaceutical Industry multiplicity expert group
Authors: Phillips Alan , Fletcher Chrissie , Atkinson Gary , Channon Eddie , Douiri Abdel , Jaki Thomas , Maca Jeff , Morgan David , Roger James Henry , Terrill Paul
Published: July 2013

In May 2012, the Committee of Health and Medicinal Products issued a concept paper on the need to review the points to consider document on multiplicity issues in clinical trials. In preparation for the release of the updated guidance document, Statisticians in the Pharmaceutical Industry held a one‐day expert group meeting in January 2013. Topics debated included multiplicity and the drug development process, the usefulness and limitations of newly developed strategies to deal with multiplicity, multiplicity issues arising from interim decisions and multiregional development, and the need for simultaneous confidence intervals (CIs) corresponding to multiple test procedures. A clear message from the meeting was that multiplicity adjustments need to be considered when the intention is to make a formal statement about efficacy or safety based on hypothesis tests. Statisticians have a key role when designing studies to assess what adjustment really means in the context of the research being conducted. More thought during the planning phase needs to be given to multiplicity adjustments for secondary endpoints given these are increasing in importance in differentiating products in the market place. No consensus was reached on the role of simultaneous CIs in the context of superiority trials. It was argued that unadjusted intervals should be employed as the primary purpose of the intervals is estimation, while the purpose of hypothesis testing is to formally establish an effect. The opposing view was that CIs should correspond to the test decision whenever possible. Copyright © 2013 John Wiley & Sons, Ltd.
Average consensus of continuous‐time multi‐agent systems with quantized communication
Authors: Wu Yongjun , Wang Long
Published: July 2013

This paper focuses on the average consensus problem of first‐order and second‐order continuous‐time multi‐agent systems with logarithmic quantized information transmission. The balanced and strongly connected digraphs are utilized to characterize the interaction topologies between agents. Based on the state estimation, distributed state updating mechanisms are introduced for every agent such that all agents’ states achieve average consensus asymptotically. By means of differential inclusion theory, we discuss the existence and convergence property of the Krasovskii solutions to the closed‐loop system models. By designing the proper control gain parameters and quantizer accuracy, two sufficient conditions are established to guarantee the achievement of average consensus. Finally, two numerical simulations are provided to illustrate the effectiveness of theoretical results. Copyright © 2013 John Wiley & Sons, Ltd.
A case study of software process improvement with CMMI‐DEV and Scrum in Spanish companies
Authors: Garzás Javier , Paulk Mark C.
Published: July 2013

One of the most commonly used agile methods is Scrum. Capability Maturity Model Integration for Development (CMMI‐DEV) is currently the de facto framework for process improvement and for determining the organizational maturity of software development companies. CMMI‐DEV and Scrum share certain characteristics, and even though they were developed for different purposes, they can be complementary to each other; and as such, they are not in competition. This paper presents a case study of the relationship between level 2 of CMMI‐DEV 1.3 and Scrum. This research has focused on the relationships between Scrum and level 2 of CMMI‐DEV 1.3. The objective of this research paper is to evaluate how Scrum helps implement a process model such as CMMI‐DEV.

A detailed case study was conducted among Spanish IT companies. The case study was designed according to established guidelines for cases studies. There were eight principal activities: case study design, case selection, case study procedures and roles, data collection, analysis, plan validity, study limitations, and reporting.

The results obtained show that most of the process areas of CMMI‐DEV level 2 had been improved by using Scrum. Other issues detected arose during the formal appraisals and illustrated how it is possible to verify with Scrum that the specific goals of CMMI‐DEV have been implemented. In addition, it highlights how the use of open‐source tools was useful in improving the process in the companies involved. Based on the case study carried out, the addition of Scrum methodologies may improve the increase in quality of software processes. Copyright © 2013 John Wiley & Sons, Ltd.
Re: Cerebroplacental ratio in prolonged pregnancy. F. D'Antonio, D. Patel, N. Chandrasekharan, B. Thilaganathan and A. Bhide. Ultrasound Obstet Gynecol 2013; 42: 196–200
Authors: Bahado‐Singh R. O.
Published: July 2013

Linked Comment: Ultrasound Obstet Gynecol 2013:42:196–200
Clinical Issues‐August 2013
Authors: Ogg Mary J. , Conner Ramona L.
Published: July 2013

This Month

Eye protection in the OR

Key words: eye protection, blood splatter, bloodborne pathogens, standard precautions.

Types of acceptable eye protection

Key words: eye protection, goggles, face shield, bloodborne pathogens, personal protective equipment, PPE.

Caring for patients with cardiovascular implantable electronic devices

Key words: electrosurgery, implantable cardioverter defibrillator, ICD, implantable electronic device, IED, cardiovascular implantable electronic device, CIED, implantable pacemaker.

Determining acceptable clinical situations for immediate use steam sterilization (IUSS)

Key words: flash sterilization, ophthalmology, immediate use steam sterilization, IUSS, cleaning and decontamination.
Implementing AORN Recommended Practices for a Safe Environment of Care
Authors: Hughes Antonia B.
Published: July 2013

Providing a safe environment for every patient undergoing a surgical or other invasive procedure is imperative. AORN's “Recommended practices for a safe environment of care” provides guidance on a wide range of topics related to the safety of perioperative patients and health care personnel. The recommendations are intended to provide guidance for establishing best practices and implementing safety measures in all perioperative practice settings. Perioperative nurses should be aware of risks related to musculoskeletal injuries, fire, equipment, latex, and chemicals, among others, and understand strategies for reducing the risks. Evidence‐based recommendations can give practitioners the tools to guide safe practice.
Activation of bile salt dependent lipase by (lyso)phosphatidic acid and platelet activating factor
Authors: Fontbonne Hervé , Puigserver Antoine , Bouza Bernard , Lombardo Dominique , Ajandouz El Hassan
Published: July 2013

The activity of breast milk BSDL was assayed with or without phospholipids as extra‐intestinal effector candidates. Phosphatidic acid, lysophosphatidic acid and platelet activating factor but not phosphatidylcholine and lysophosphatidylcholine stimulated BSDL activity at least as efficiently as taurocholate. The apparent dissociation constants of PA and LPA at saturating concentrations of three different substrates were between 0.1 and 13.4 μM and that of PAF was below or equal to 200 pM. Kinetic data suggested the existence of at least one binding site for each of these effectors. PA, LPA and PAF are likely extra‐intestinal modulators of BSDL activity.
Characterization ofDicrocoelium dendriticumisolates from small ruminants in Shaanxi Province, north-western China, using internal transcribed spacers of nuclear ribosomal DNA
Authors: Bian Q.Q. , Zhao G.H. , Jia Y.Q. , Fang Y.Q. , Cheng W.Y. , Du S.Z. , Ma X.T. , Lin Q.
Published: July 2013

The genetic variations in internal transcribed spacers (ITS) spanning ITS-1, 5.8S and ITS-2 rDNA ofDicrocoelium dendriticum, isolated from sheep and goats in four geographical regions in Shaanxi province, were examined. The lengths of ITS-1, 5.8S and ITS-2 rDNA sequences forD. dendriticumwere 749 bp, 161 bp and 234 bp, respectively. Intra-specific sequence variations ofD. dendriticumwere 0–0.5% for ITS-1 and 0–1.3% for ITS-2 rDNA, while the inter-specific variations among species in genusDicrocoeliumin ITS-2 rDNA were 3.4–12.3%. Phylogenetic analysis based on sequences of ITS-2 rDNA showed that allD. dendriticumisolates in the present study were grouped with referenceD. dendriticumisolates from sheep and goats, andD. dendriticumisolates from cattle and Japanese serow were clustered in a sister clade. However, the phylogenetic tree could not reveal geographically genetic relationships ofD. dendriticumisolates in different origins and hosts. These findings provided basic information for further study of molecular epidemiology and control ofD. dendriticuminfection in Shaanxi province as well as in the world.
Knowing, reasoning and visualizing in industrial design
Authors: Woelfel Christian , Krzywinski Jens , Drechsel Frank
Published: July 2013

Industrial design processes can be described as human design problem solving, incorporating the acquisition, evaluation, production and transfer of specific knowledge. In this paper, we will describe the connection and interaction between visualization and reasoning during different stages of the design process. Thereby we focus on three early stages of this process: clarifying the task, concepting and designing an overall solution.

This paper provides a rather general description of design processes and more detailed remarks on design knowledge and design actions. It specifically focuses on design concepts as visual key elements in industrial design processes. We will address the importance of externalization and visualization as means for thinking and knowledge generation and transfer in industrial design in general.

The design process is described as an interplay of the parallel and iterative developments of three domains: knowledge, concept and design. In contrast to linear schemes, this paper proposes a design process scheme focusing on iterative circles and parallel processing possibilities. Industrial design knowledge will be described and compared to relevant knowledge in other disciplines, in particular, engineering design knowledge. We will describe the strong link between the designer's individual biographies, design knowledge and the outcome of design processes.

Design concepts will be discussed as extremely compact representations of core characteristics of the artifacts to be designed, serving as a guide to the design process.

Design actions as described in this paper are characterized by the simultaneous occurrence of thought and externalization processes. Different kinds of visualization are discussed in regard of their role in reasoning during industrial design processes.

This paper concludes by sketching two perspectives. One addresses the need for interdisciplinary research on new visualization tools with regard to human reasoning in design processes. The second one gives an impression of how visualization tools and methods of industrial design can supplement other disciplines.
International outbreak investigation of Salmonella Heidelberg associated with in-flight catering
Authors: REBOLLEDO J. , GARVEY P. , RYAN A. , O'DONNELL J. , CORMICAN M. , JACKSON S. , CLOAK F. , CULLEN L. , SWAAN C. M. , SCHIMMER B. , APPELS R. W. , NYGARD K. , FINLEY R. , SREENIVASAN N. , LENGLET A. , GOSSNER C. , McKEOWN P.
Published: July 2013

Rapid and wide dispersal of passengers after flights makes investigation of flight-related outbreaks challenging. An outbreak ofSalmonellaHeidelberg was identified in a group of Irish travellers returning from Tanzania. Additional international cases sharing the same flight were identified. Our aim was to determine the source and potential vehicles of infection. Case-finding utilized information exchange using experts' communication networks and national surveillance systems. Demographic, clinical and food history information was collected. Twenty-five additional cases were identified from Ireland, The Netherlands, Norway, USA and Canada. We conducted a case-control study which indicated a significant association between illness and consumption of milk tart (OR 10·2) and an egg dish (OR 6) served on-board the flight. No food consumed before the flight was associated with illness. Cases from countries other than Ireland provided supplementary information that facilitated the identification of likely vehicles of infection. Timely, committed international collaboration is vital in such investigations.
Secure Scalable Disaster Electronic Medical Record and Tracking System
Authors: DeMers Gerard , Kahn Christopher , Johansson Per , Buono Colleen , Chipara Octav , Griswold William , Chan Theodore
Published: July 2013

Introduction

Electronic medical records (EMRs) are considered superior in documentation of care for medical practice. Current disaster medical response involves paper tracking systems and radio communication for mass-casualty incidents (MCIs). These systems are prone to errors, may be compromised by local conditions, and are labor intensive. Communication infrastructure may be impacted, overwhelmed by call volume, or destroyed by the disaster, making self-contained and secure EMR response a critical capability.

Report

As the prehospital disaster EMR allows for more robust content including protected health information (PHI), security measures must be instituted to safeguard these data. The Wireless Internet Information System for medicAl Response in Disasters (WIISARD) Research Group developed a handheld, linked, wireless EMR system utilizing current technology platforms. Smart phones connected to radio frequency identification (RFID) readers may be utilized to efficiently track casualties resulting from the incident. Medical information may be transmitted on an encrypted network to fellow prehospital team members, medical dispatch, and receiving medical centers. This system has been field tested in a number of exercises with excellent results, and future iterations will incorporate robust security measures.

Conclusion

A secure prehospital triage EMR improves documentation quality during disaster drills.

DeMersG, KahnC, JohanssonP, BuonoC, ChiparaO, GriswoldW, ChanT. Secure scalable disaster electronic medical record and tracking system. Prehosp Disaster Med. 2013;28(5):1-4.
“How Far Do You Go and Where Are the Issues Surrounding That?” Dilemmas at the Boundaries of Clinical Competency in Humanitarian Health Work
Authors: Hunt Matthew R. , Schwartz Lisa , Fraser Veronique
Published: July 2013

You go from here to there, and here you're specialized in one particular sort of thing, there you may be asked to do all sorts of things outside your specialty. How far do you go and where are the issues surrounding that?

Canadian physician discussing experiences in humanitarian aid work

Health professionals working in humanitarian relief projects encounter a range of ethical challenges. Applying professional and ethical norms may be especially challenging in crisis settings where needs are elevated, resources scarce, and socio-political structures strained. Situations when clinicians must decide whether to provide care that is near the margins of their professional competency are a source of moral uncertainty that can give rise to moral distress. The authors suggest that responding ethically to these dilemmas requires more than familiarity with ethical codes of conduct and guidelines; it requires practical wisdom, that is, the ability to relate past experience and general guidance to a current situation in order to render a morally sound action. Two sets of questions are proposed to guide reflection and deliberation for clinicians who face competency dilemmas. The first is prospective and intended to aid clinicians in evaluating an unfolding situation. The second is retrospective and designed to support debriefing about past experiences and difficult situations. The aim of this analysis is to support clinicians in evaluating competency dilemmas and provide ethical care and services.

HuntMR,SchwartzL,FraserV.“How Far Do You Go and Where Are the Issues Surrounding That?” Dilemmas at the Boundaries of Clinical Competency in Humanitarian Health Work.Prehosp Disaster Med.2013;28(5):1-7.
Association of 25-hydroxyvitamin D with Hb and lead in children: a Chinese population-based study
Authors: Chang Li , Liu Xiaojuan , Shi Hua , Dai Wei , Wang Hong , Jiang Yongmei
Published: July 2013

Objective

To evaluate the prevalence of vitamin D deficiency and insufficiency, as well as their association with Hb and elevated blood lead levels (BLL) in children in China.

Design

A cross-sectional and 1-year retrospective study.

Setting

Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, China.

Subjects

Children aged from 6 months to 14 years living in south-west China who were taken to physical examinations (January–December 2011).

Results

Of 1218 children included in the study, 25-hydroxyvitamin D (25(OH)D) concentration (mean 33·18 (sd 16·48) ng/ml) was deficient in 21·6 % and insufficient in 27·4 %, which were higher than the prevalence of both anaemia at 8·5 % and elevated BLL (Pb ≥ 10 μg/dl) at 1·8 %, but lower than mildly elevated BLL prevalence (5 μg/dl ≤ Pb < 10 μg/dl) at 56·9 %. There was a negative correlation between 25(OH)D concentration and BLL (r = −0·216, P < 0·001) while no significant relationship was found between 25(OH)D concentration and Hb (r = −0·012, P > 0·05). After multivariable adjustment, the significant predictors of 25(OH)D deficiency and insufficiency were increasing child age especially between 8 and 14 years (OR = 18·29; 95 % CI 10·14, 32·99; P < 0·001) and BLL (OR = 1·01; 95 % CI 1·00, 1·02; P = 0·045).

Conclusions

The prevalence of 25(OH)D deficiency and insufficiency was much higher than that of anaemia or elevated BLL in south-west China, and associated with increasing age and BLL.
Genetic diversity analyses of Brassica napus accessions using SRAP molecular markers
Authors: Ahmad Riaz , Farhatullah  , Quiros Carlos F. , Rahman Hidayatur , Swati Zahoor Ahmad
Published: July 2013

Knowledge about genetic diversity among Brassica napus cultivars developed for many growing regions and their possible use as potential inbred lines for hybrid seed production is limited. We studied the genetic diversity and relationships among B. napus accessions using Sequence Related Amplified Polymorphism (SRAP) markers, which preferentially amplify open reading frames. A total of 60 spring-type B. napus accessions were screened using 20 SRAP primers, which revealed 162 polymorphic fragments with an average of eight markers per primer combination. Genetic similarity estimates ranged from 40 to 100, which indicated sufficient diversity among the accessions. The majority of the accessions were uniquely identified by the markers with the exception of near-isogenic inbred lines. Cluster analysis displayed five major groups. The first major cluster comprised 23 accessions mostly of Australian origin, whereas the second cluster included 13 accessions mostly of Canadian origin. The accessions in the first and second clusters were identified as maintainers of cytoplasmic male sterility. The two restorer lines R-111 and R-101 along with their corresponding backcross progeny constituted the third cluster. Scandinavian cultivars made the fourth separate cluster. One cultivar Salam and its respective inbred line were the most divergent lines. Variations in the number of markers between open-pollinated cultivars and their respective selfed inbred lines were also observed. The clustering pattern mostly supported their respective pedigree and characteristic traits. Genetic diversity in genetically distinct groups in the tested maintainer and restorer lines can be exploited for hybrid development in B. napus.