bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of microwave‐assisted pulse‐spouted bed freeze‐drying (MPSFD) on volatile compounds and structural aspects of Cordyceps militaris
Authors: Wu Xiao‐fei , Zhang Min , Bhandari Bhesh , Li Zhongqin
Published: March 2018

BACKGROUND

Microwave‐assisted pulse‐spouted bed freeze‐drying (MPSFD) uses microwave heating to substitute the customary conduction heating during freeze drying (FD), resulting in high‐quality dried samples with a short drying time. The aim of this study was to determine the effect of MPSFD on volatile compounds and structural aspects of Cordyceps militaris. In order to highlight the effect of MPSFD, FD (recognized for its high‐quality products) and hot‐air dying (HD; the most commonly used) were also evaluated using headspace solid‐phase micro‐extraction combined with gas chromatography–mass spectrometry and mid‐Fourier transform infrared spectroscopy.

RESULTS

Sixty‐two components were obtained by FD, 62 compounds by MPSFD and 39 by HD. FD and MPSFD exhibited much better effects on the retention of volatile components of C. militaris than HD. Principal component analysis, hierarchical clustering analysis and E‐nose analysis indicated that the volatile compounds of C. militaris dried by FD and MPSFD were similar. The spectral features of FD and MPSFD samples were also similar, whereas the HD sample presented a clearly different spectral feature around a wavenumber of 1640 cm−1.

CONCLUSION

MPSFD exhibited a beneficial effect on aroma and structure retention, with shorter drying time and lower energy consumption. © 2018 Society of Chemical Industry
Duck nest depredation, predator behavior, and female response using video
Authors: Croston Rebecca , Ackerman Joshua T. , Herzog Mark P. , Kohl Jeffrey D. , Hartman C. Alex , Peterson Sarah H. , Overton Cory T. , Feldheim Cliff L. , Casazza Michael L.
Published: March 2018

Depredation plays an important role in determining duck nest success and predator and female duck behavior during nest depredation can influence nest fate. We examined depredation of mallard (Anas platyrhynchos) and gadwall (A. strepera) nests in Suisun Marsh, California, USA, in 2015–2016 with continuous infrared video monitoring to identify nest predators and characterize predator and female duck behavior during depredation events. We recorded predators at 44% of 147 nests monitored. Raccoons (Procyon lotor) were the most frequent predator observed at nests (40% of nests visited and 53% of depredated eggs) followed by striped skunks (Mephitis mephitis; 27% and 27%), coyotes (Canis latrans; 4% and 9%), common ravens (Corvus corax; 4% and 9%), gopher snakes (Pituophis catenifer catenifer; 19% and 0%), and western yellow‐bellied racers (Coluber constrictor mormon; 1% and 0%). The number of eggs depredated per depredation bout varied among predators (raccoons: 7.3 eggs; skunks: 2.5; coyotes: 7.4; ravens: 7.7; and snakes: 0.0). Mammal depredation occurred between 1600 and 0400, whereas snakes and ravens were observed at nests during the day (snakes: 1000–2100; ravens: 1700). Females flushed from nests immediately before predator arrival ( = 29.0 ± 16.6 [SD] sec), and this timing did not vary among predators. However, the length of nest depredation bouts varied among predators. Nest visits by gopher snakes were longer (18.6 ± 19.4 min) than depredation bouts by other predators (12.3 ± 10.7 min), but snakes did not successfully consume any eggs. Females took more time to return to nests when nests were depredated by raccoons (239 ± 137 min), whereas females returned more quickly when nests were visited by skunks (81 ± 163 min) or gopher snakes (15 ± 128 min). Partial clutch depredation occurred at 15% of depredated nests, but only 23% of partially depredated nests successfully hatched ≥1 egg. Our results indicate that predator type and behavior can influence female behavior and nest fate, and that management actions that reduce the effectiveness of raccoons and skunks encountering waterfowl nests may benefit these nesting populations. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
Double‐clad fiber Michelson interferometer for measurement of temperature and refractive index
Authors: Musa S. M. A. , Baharin N. F. , Azmi Asrul Izam , Ibrahim R. K. Raja , Abdullah A. S. , Mohd Noor M. Y. , Qi Haifeng
Published: March 2018

An all‐fiber Michelson interferometer based on double‐clad fiber (DCF) is proposed for temperature and refractive index (RI) sensing. The sensor is formed by continuous splicing between single mode fiber, multimode fiber, and DCF. Temperature measurement is achieved by monitoring the dip wavelength shift of the interferometer spectra resulting from thermo‐optic effect on core and first cladding of DCF. RI measurement is established from the power change in spectra due to the Fresnel's reflection at the DCF tip. Experimental result on 18.5 mm sensor manifests that temperature and RI responses are distinguishable. For instance, power level at 1540.5 nm exhibits quadratic shift to RI changes while unaffected to temperature changes. Dip wavelengths of sensor spectra demonstrate linear shift to temperature changes while unaffected by RI changes. The proposed sensor is cost effective as sensor fabrication only requires conventional splicing. Sensor capability to distinguish temperature and RI parameters makes it practical for broad range applications including for biomedical and food industries.
A fully tunable two‐pole bandpass filter with wide tuning range based on half mode substrate integrated waveguide
Authors: Lan Bozhang , Guo Chenjiang , Ding Jun
Published: March 2018

A two‐pole tunable bandpass filter (BPF) which allows for the operational agility of both center frequency and bandwidth is proposed in this article. The fundamental structure is based on half mode substrate integrated waveguide (HMSIW) with different dimensions. Two sets of varactors placed at various nodes separately are utilized for adjusting center frequency and bandwidth over a wide tuning range. By adding a source‐load coupling path, two transmission zeros are produced on both sides of the passband to improve filter selectivity significantly. A second‐order 1.52–2.76 GHz filter with 3 dB constant bandwidth tuning from 240 to 350 MHz is developed, analyzed, simulated, and fabricated. Good agreement is obtained between simulated and experimental results.
A novel illumination‐efficient dimming control scheme based on reversed unipolar return‐to‐zero coding and circular (7, 1) modulation in high‐speed visible light communication
Authors: Zhao Jiaqi , Chi Nan
Published: March 2018

Visible light communication (VLC) is an emerging optical wireless communication, which combines lighting and communication simultaneously. In indoor VLC systems, the brightness of LEDs should be dimmed to a certain level to support the illumination function. In this article, we propose a novel dimming control scheme based on Reversed Unipolar Return‐to‐Zero (RURZ) coding and circular (7, 1) modulation. The dimming level is determined by the duty cycle ratio (DCR) of the RURZ codes. Contrary to traditional RZ coding, with the decrease of DCR, the component of high‐level signal in RURZ codes increases and could constantly keep LEDs on. Therefore, when the DCR is smaller, the time that the LED is on keeps longer and the illumination efficiency is higher. A special shaped 8‐QAM modulation scheme called circular (7, 1) is employed to obtain a wider dimming range and higher communication quality for its superiority in operation range and bit error ratio (BER) performance. Furthermore, pulse shaping technology is utilized to suppress the wide spectrum extended by RURZ coding and increase the spectral efficiency (SE) and the data rate. Theoretical analysis and experimental investigation demonstrate that the RURZ coded and circular (7, 1) modulated VLC system could achieve a wide dimming range with high illumination efficiency and high communication speed. An illumination efficiency improvement of 0.63 is successfully achieved at 30% DCR with a data rate of 1.35 GB/s over 1 m free space transmission.
Low‐frequency detection of acoustic signals using fiber as an ultrasonic guide with a distant in‐fiber Bragg grating
Authors: Leal Wescley A. , Carneiro Mateus B. R. , Freitas Taiane A. M. G. , Marcondes Cláudia B. , Ribeiro Ricardo M.
Published: March 2018

This article shows the development of a photonic detector of low‐frequency ultrasonic signals. These signals latter reach a sensitive single‐mode optical fiber as an acoustic guide conveying the signals (around 43 kHz) over 70 cm to a distant and protected in‐fiber Bragg grating. The grating reflects a spectrum centered around 1550 and 2.6 nm bandwidth and is interrogated by a tunable laser in their linear and most sensitive region. As a result, real‐time passive demodulation of communication or monitoring of ultrasonic signals propagating through solid materials is possible. The detector may also be applied to other physical media. In this study, a new passive technique to thermally desensitize the fiber‐Bragg gratings (FBG) is also proposed, though the proposed technique is not experimentally tested.
Broadband circularly polarized patch antenna with low crosspolarization using artificial ground structure
Authors: Kai Yujiro , Fukusako Takeshi
Published: March 2018

This letter proposes a circularly polarized patch antenna with 3‐dB AR (axial ratio) and reasonably constant gain characteristics and low crosspolarization covering a wide bandwidth using an AGS (artificial ground structure). The AGS with a rectangular unit cell can expand the 3‐dB axial ratio of CP (circular polarization) and impedance characteristics of circularly polarized patch antennas. For achieving the broadband impedance characteristics, a matching structure is required to keep a sufficient impedance bandwidth between the two parallel resonances separated with a large ratio of frequency. As the matching structure, the outer conductor of a feeding coaxial cable passing through the ground plane is extended to be close to the radiating patch element. However, such matching structure yields large XPOL (crosspolarization) in off‐boresight directions. In this letter, the extended coaxial structure is replaced with a meandering probe for suppressing XPOL and matching impedance. The effect of the meandering probe is discussed with simulated and measured results. As a result, the proposed structure achieves a −10‐dB S11 bandwidth of around 50% and a 3‐dB AR bandwidth of 20%, respectively. The average gain of 7.8 dBic is achieved covering the AR bandwidth. Furthermore, off‐boresight XPOL decreases by around 10 dB compared to the previous structure with the extended coaxial structure in ±30° directions.
Dual notch band UWB antenna with improved notch characteristics
Authors: Sohail Amir , Alimgeer Khurram Saleem , Iftikhar Adnan , Ijaz Bilal , Kim Kang Wook , Mohyuddin Wahab
Published: March 2018

In this article, a novel design of a compact planar Ultra Wideband (UWB) monopole antenna with dual band notched characteristics has been presented. The antenna has a unique structure meeting UWB standards. The proposed antenna is fed through a
micro strip feed line, whereas a better impedance is achieved by truncating the ground plane. The dual notches are achieved by incorporating a meandered slot on the radiator patch and U‐slot in the feed line. The antenna is fabricated on FR‐
substrate having a compact size of
. A good agreement is observed between measured and simulated results. The radiation pattern is omnidirectional in H‐plane, whereas dipole like radiation pattern is observed in the E‐plane. The gain of antenna is stable across the whole UWB except at notched bands. It is shown that any UWB can be notched at any desired frequency band by incorporating appropriate slot length.
A switched‐beam millimeter‐wave array with MIMO configuration for 5G applications
Authors: Ikram Muhammad , Sharawi M. S. , Klionovski K. , Shamim A.
Published: March 2018

In this work, a switched‐beam 2‐element multiple‐input multiple‐output (MIMO) antenna system is proposed at mm‐wave bands for 5G applications. The antenna system consists of a 4 × 4 connected slot antennas for each MIMO element forming the connected antenna array (CAA). A feed network based on a Butler matrix is used to excite the CAA, in addition to steer the beam at different locations which enhance the diversity performances. The mm‐wave MIMO antenna system operates at 28 GHz with at least −10 dB measured bandwidth of 830 MHz (27.4 GHZ–28.23 GHz). It is fabricated on a commercially available RO3003 substrate with dielectric constant of 3.3 and height of 0.13 mm, respectively. The dimensions of the board are equal to 150 mm3 × 100 mm3 × 0.13 mm3. The proposed design is compact, low profile, and suitable for future 5G‐enabled tablet PCs.
A UWB sensor based on resistively‐loaded dipole antenna for skull healing on cranial surgery phantom models
Authors: Lee Doojin , Nowinski Daniel , Augustine Robin
Published: March 2018

After craniotomy, the monitoring of the skull healing progression is strongly needed to take a proper medical intervention. The CT scans is however currently used for follow‐up after craniotomy resulting in lack of an effective and safety problem. This research proposes an alternative for monitoring the skull healing using ultra‐wide band (UWB) antenna. For the healing of the skull surgical defect, a compact resistively‐loaded dipole antenna is designed and analyzed in terms of its performance in the time domain. The head phantoms having a wideband characteristic are fabricated and used as models for the skull healing process. To represent various mineralization stages, phantoms with various dielectric constants from hydrogel scaffold to the normal skull and their intermediate values are used. The UWB radar technique in the time domain is implemented in the healing process of skull injuries emulating cranial cavities that are made as part of craniosynostosis treatment. The measurement results at the defect area show that the variations in amplitude of the reflected pulse as the skull healing is progressed. The results obtained can contribute to the development of microwave‐based techniques as a preliminary study of a proof concept before clinical trial in the healing process after cranial surgery.
Bandwidth enhancement of Salisbury screen microwave absorber using wire metamaterial
Authors: Bhati Amit , Hiremath Kirankumar R. , Dixit Vivek
Published: March 2018

A new design approach that enhances the bandwidth of conventional Salisbury Screen (SS) microwave absorber is investigated. The absorber comprises of, wire metamaterial printed on FR4 substrate, placed on the top of the SS. The SS consists of 50 Ω/sq resistive sheet placed on the metal backed dielectric spacer. The theoretical analysis indicates the bandwidth of SS for −10 dB reflection is 41.1% using FR4 as a spacer for the optimum sheet resistivity of 308 Ω/sq. The proposed absorber shows the bandwidth of 53.5% (8.9–15.4 GHz) for −10 dB reflection. The thickness of the absorber is 0.15 λL (lowest cut‐off frequency for −10 dB reflection). The FR4 substrate with SS works as Jaumann configuration and introduces an additional resonance mode. The selective overlapping of resonant mode excited by wire metamaterial and the additional resonance mode enhances the bandwidth of the absorber. The wire metamaterial is physically realized using low‐cost screen printing technique. The good agreement between the simulated and measured data has been observed.
Millimeter‐wave planar antenna on flexible polyethylene terephthalate substrate with water base silver nanoparticles conductive ink
Authors: Pourahmadazar Javad , Denidni Tayeb A.
Published: March 2018

A 60 GHz, mm‐wave array antenna, mounted on a thin flexible polyethylene terephthalate substrate is presented. The proposed 16
8 microstrip series fed array antenna prototype used with laboratory made silver nanoparticles conductive ink used in inkjet technology. The main fabrication problem for this prototype is addressed via ink formulation for printing a homogeneous layer with an excellent electrical conductivity. In comparison to the previous millimeter‐wave series feed structures, the proposed antenna feed network conductive traces 50% is reduced. Silver base conductive ink is prepared in the laboratory with a viscosity of 9–12 cP and a surface tension of 27–32 mN/m for use in Fujifilm DMP‐2831 series. The realized design validate performances of 16‐element linear series sub‐array fed by a three‐stage T‐junction power‐divider network that achieves a 24 dBi gain is presented.
Dielectric resonator antenna array for X‐band and microwave imaging applications
Authors: Gupta Anshul , Reddy Sreeja , Gangwar Ravi Kumar
Published: March 2018

In this article, simulation and experimental studies of compact dielectric resonant antenna array have been performed for microwave imaging systems and X‐band applications. A novel feed structure has been proposed to excite the four cylindrical dielectric resonators. The proposed antenna array shows dual band characteristics i.e., 4.15–7.2 GHz and 9.35–17.2 GHz with the bandwidth of 3.05 GHz and 7.85 GHz respectively. The proposed antenna has been fabricated and tested. Measurement results have been extracted and found in good agreement with simulated results. The proposed antenna array affords appropriate gain, high radiation efficiency, wide bandwidth, small size, and stable radiation patterns over the entire bands which are essential performance characteristics to be utilized for C band, X band, and Ku band applications.
Design of a wide bandwidth and high efficiency circularly polarized microstrip patch antenna using coaxial feeding technique
Authors: Hossain Sheikh Dobir , Rita  , Sobahan K. M. Abdus , Mallick Rony , Hossain F.
Published: March 2018

A single band circularly polarized rectangular microstrip patch antenna has been simulated from the cavity equation at first and then the antenna design has been extended to 2 × 2 array. The length and thickness of the each element of the rectangular patch antenna with a slot in the center of the rectangular patch are 38 mm and 0.1 mm, respectively, which are comparatively smaller than our previously presented single‐element circularly polarized microstrip antenna with an I‐slot. In comparison to the bandwidth and efficiency of single element antenna, the quantity have increased about 39% and more than 90%, respectively, in the desired array antenna at the same resonant frequency that is 2.8 GHz. In this article, we also have studied and presented the return loss, bandwidth, gain, directivity, axial ratio of our aimed antenna.
Parametric studies on hexagonal ring based aperture and patch type curved frequency selective surface
Authors: Begam N. , Sarkar S. , Samaddar P. , Saha S. , Chanda (Sarkar) D. , Sarkar P. P.
Published: March 2018

Simulated and experimental investigations on hexagonal ring based aperture and patch type semi cylindrical curved frequency selective surfaces (FSSs) have been presented. Simulated and experimental results are in good agreement. Also, the parametric studies have been done for patch and aperture type Curved FSSs. Curved FSS structures are recently being investigated to design radome or nose of fighter aeroplane. This study will help the researchers to design curved frequency selective structures with both band pass and band stop properties.
Compact X‐band bandpass filter using stub‐loaded T‐shape resonator with source‐load coupling
Authors: Zheng Yiyuan , Sheng Weixing
Published: March 2018

A novel compact X‐band bandpass filter with a flat and wide passband as well as enhanced out‐of‐band performance is presented based on a source‐load coupling architecture. The proposed architecture is symmetrically constructed of a pair of stepped‐impedance feed structures and an embedded T‐shape resonator, substantially improving the filter's frequency selectivity and passband performance. In order to obtain a broader stopband region, a set of stubs is loaded at the edges of the tapped open stub in the T‐shape resonator. By utilizing a two‐layer low temperature co‐fired ceramic substrate, a prototype filter is implemented and verified experimentally. The filter achieves promising properties of compact size, low‐loss wide passband, high selectivity and good stopband performance simultaneously with an uncomplicated geometry including neither vias nor intricate strips, which exhibits a fairly good potential to be stably used in the highly integrated X‐band microwave systems.
Circularly polarized slot antenna with three‐dimensional ring‐shaped ground plane
Authors: Ko Ting‐Hung , Row Jeen‐Sheen
Published: March 2018

A novel design for circularly polarized antennas with broadband operation is proposed. The proposed antenna structure can be regarded as a three‐dimensional version of a planar ring slot antenna, but no printed circuit board is involved in the structure. Moreover, the circular polarization radiation is achieved by introducing a shorting post into the antenna structure as a perturbation element. Measured results indicate that the 3‐dB‐axial‐ratio bandwidth of the proposed antenna is two times larger than that of the printed ring slot antenna with the same aperture size. Simulation results obtained with HFSS also agree well with the experimental data.
A miniaturized UWB monopole antenna with five‐section ground plane slit
Authors: Ul Haq Muhammad Aziz , Koziel Slawomir
Published: March 2018

A practical miniaturized ultra‐wideband monopole antenna with a five‐section ground plane slit is proposed. The structure is a modification of a reference antenna designed with the two‐section ground plane slit and featuring the footprint area of 216 mm2. To reduce the antenna size, a ground plane modification was introduced in the form of a five‐section slit below the feeding line. Furthermore, all geometry parameters of the structure were simultaneously optimized. The final design exhibits a small size of only 22.5 × 7.9 mm2 with footprint of 178 mm2 and good electrical and field characteristics. Experimental validation and comparisons with recently reported designs are also provided.
Volumetric segmentation‐free method for rapid visualization of vascular wall shear stress using 4D flow MRI
Authors: Masutani Evan M. , Contijoch Francisco , Kyubwa Espoir , Cheng Joseph , Alley Marcus T. , Vasanawala Shreyas , Hsiao Albert
Published: March 2018

Purpose

To develop a rapid segmentation‐free method to visualize and compute wall shear stress (WSS) throughout the aorta using 4D Flow MRI data. WSS is the drag force‐per‐area the vessel endothelium exerts on luminal blood; abnormal levels of WSS are associated with cardiovascular pathologies. Previous methods for computing WSS are bottlenecked by labor‐intensive manual segmentation of vessel boundaries. A rapid automated segmentation‐free method for computing WSS is presented.

Theory and Methods

Shear stress is the dot‐product of the viscous stress tensor and the inward normal vector. The inward normal vectors are approximated as the gradient of fluid speed at every voxel. Subsequently, a 4D map of shear stress is computed as the partial derivatives of velocity with respect to the inward normal vectors. We highlight the shear stress near the wall by fusing visualization with edge‐emphasized anatomical data.

Results

As a proof‐of‐concept, four cases with aortic pathologies are presented. Visualization allows for rapid localization of pathologic WSS. Subsequent analysis of these pathological regions enables quantification of WSS. Average WSS during peak systole measures approximately 50–60 cPa in nonpathological regions of the aorta and is elevated in regions of stenosis, coarctation, and dissection. WSS is reduced in regions of aneurysm.

Conclusion

A volumetric technique for calculation and visualization of WSS from 4D Flow MRI data is presented. Traditional labor‐intensive methods for WSS rely on explicit manual segmentation of vessel boundaries before visualization. This automated volumetric strategy for visualization and quantification of WSS may facilitate its clinical translation.
A mixed‐order nonlinear diffusion compressed sensing MR image reconstruction
Authors: Joy Ajin , Paul Joseph Suresh
Published: March 2018

Purpose

Avoid formation of staircase artifacts in nonlinear diffusion‐based MR image reconstruction without compromising computational speed.

Methods

Whereas second‐order diffusion encourages the evolution of pixel neighborhood with uniform intensities, fourth‐order diffusion considers smooth region to be not necessarily a uniform intensity region but also a planar region. Therefore, a controlled application of fourth‐order diffusivity function is used to encourage second‐order diffusion to reconstruct the smooth regions of the image as a plane rather than a group of blocks, while not being strong enough to introduce the undesirable speckle effect.

Results

Proposed method is compared with second‐ and fourth‐order nonlinear diffusion reconstruction, total variation (TV), total generalized variation, and higher degree TV using in vivo data sets for different undersampling levels with application to dictionary learning‐based reconstruction. It is observed that the proposed technique preserves sharp boundaries in the image while preventing the formation of staircase artifacts in the regions of smoothly varying pixel intensities. It also shows reduced error measures compared with second‐order nonlinear diffusion reconstruction or TV and converges faster than TV‐based methods.

Conclusion

Because nonlinear diffusion is known to be an effective alternative to TV for edge‐preserving reconstruction, the crucial aspect of staircase artifact removal is addressed. Reconstruction is found to be stable for the experimentally determined range of fourth‐order regularization parameter, and therefore not does not introduce a parameter search. Hence, the computational simplicity of second‐order diffusion is retained.
The effect of neutralization of nerve growth factor (NGF) on bladder and urethral dysfunction in mice with spinal cord injury
Authors: Wada Naoki , Shimizu Takahiro , Shimizu Nobutaka , de Groat William C. , Kanai Anthony J. , Tyagi Pradeep , Kakizaki Hidehiro , Yoshimura Naoki
Published: March 2018

Aims

To investigate the role of nerve growth factor (NGF) in lower urinary tract dysfunction in mice with spinal cord injury (SCI).

Methods

Using 4‐week SCI mice, single‐filling cystometry and external urethral sphincter (EUS)‐electromyography were performed under an awake condition. In some SCI mice, anti‐NGF antibodies (10 µg/kg/h) were administered for 1 or 2 weeks before the urodynamic study. NGF levels in the bladder and L6/S1 spinal cord were assayed by ELISA. The transcript levels of P2X receptors and TRP channels in L6/S1 dorsal root ganglia (DRG) were measured by RT‐PCR.

Results

In SCI mice, the area under the curve of non‐voiding contractions (NVCs) during the storage phase was significantly decreased in both 1‐ and 2‐week anti‐NGF antibody‐treated SCI groups. However, EUS‐electromyogram parameters during voiding were not altered by the treatment. Bladder mucosal and spinal NGF levels were decreased after 2 weeks of anti‐NGF antibody treatment. TRPA1 and TRPV1 transcripts in L6/S1 DRG were significantly decreased after 1‐ or 2‐week anti‐NGF treatment.

Conclusions

In SCI mice, NGF is involved in the emergence of NVCs in association with increased expression of TRP receptors that are predominantly found in C‐fiber afferent pathways. Thus, NGF targeting treatments could be effective for treating storage problems such as detrusor overactivity after SCI.
Accelerated phase contrast MRI using hybrid one‐ and two‐sided flow encodings only (HOTFEO)
Authors: Wang Da , Chien Aichi , Shao Jiaxin , Ali Fadil Abbas , Hu Peng
Published: March 2018

The aim of this work was to develop and evaluate a fast phase contrast magnetic resonance imaging (PC‐MRI) technique with hybrid one‐ and two‐sided flow encodings only (HOTFEO) for accurate blood flow and velocity measurements of three‐directional velocity encoding PC‐MRI. Four‐dimensional (4D) PC‐MRI acquires flow‐compensated (FC) and three‐directional flow‐encoded (FE) echoes in an interleaved fashion. We hypothesize that the blood flow velocity direction (not magnitude) has minimal change between two consecutive cardiac phases. This assumption provides a velocity direction constraint that can achieve 4/3‐fold acceleration using three‐directional FE data to calculate FC data instead of acquiring them. The HOTFEO acquisition pattern can address the ill‐conditioned constraint and improve the calculation accuracy. HOTFEO was evaluated in healthy volunteers and compared with conventional two‐dimensional (2D) and 4D flow imaging techniques with FC and three‐directional FE acquisitions (FC/3FE). Compared with FC/3FE, Bland–Altman tests showed that the 4/3‐fold accelerated HOTFEO technique resulted in relatively small bias error for total volumetric flow (0.89% for prospective 2D data, –1.19% for retrospective 4D data and –3.40% for prospective 4D data) and maximum peak velocity (0.50% for prospective 2D data, –0.17% for retrospective 4D data and –2.00% for prospective 4D data) measurements in common carotid arteries. HOTFEO can accelerate three‐directional velocity encoding PC‐MRI whilst maintaining the measurement accuracy of the total volumetric flow and maximum peak velocity.
Optimality principles and decomposition of tracking controllers for weakly dual redundant systems
Authors: Corona Dario , Cristofaro Andrea
Published: March 2018

In this paper, the problem of optimizing the output regulation of a weakly dual redundant plant is addressed. When the system is underactuated, only a subset of the outputs can be arbitrarily controlled and the remaining ones are constrained. With a specific focus on the asymptotic output tracking problem for single‐input systems, we investigate the connection between the overall optimal input and the individually optimal controllers, which leads to the perfect tracking of each output reference. Such relationship is analyzed both for open‐loop and closed‐loop controllers for different cost functions and types of references, and the optimality principles are established, provided that suitable structural conditions are met by the plant matrices.
Controllable self‐assembly of polystyrene‐block‐poly(2‐vinylpyridine)
Authors: Wang Yang , Xu Xinhe , Xu Peng , Feng Xiaobo , Zhang Yanyan , Fu Feiya , Liu Xiangdong
Published: March 2018

Block copolymers can form various ordered structures by self‐assembly, and their composites with inorganic materials may give surprising properties. This review summarizes recent developments in the preparation, mechanism and application of various types of self‐assembly of polystyrene‐block‐poly(2‐vinylpyridine) (PS‐b‐P2VP). The focus of the review is on how to control the self‐assembly of the dynamic and ordered structure of PS‐b‐P2VP based materials by applying effective factors such as thermal annealing, solvent annealing, block composition and blending. Moreover, the combination of the self‐assembly of PS‐b‐P2VP and various nanoparticles, with potentials in drug delivery, sensors and catalysis, is highlighted. © 2018 Society of Chemical Industry
In situ preparation of magnetic Fe3O4.Cu2O.Fe3O4/cryogel nanocomposite powder via a reduction–coprecipitation method as adsorbent for methylene blue water pollutant
Authors: Atta Ayman M , Al‐Lohedan Hamad A , Tawfeek Ahmed M , Ahmed Mona A
Published: March 2018

Magnetic nanocomposites have attracted great attention as adsorbents for the removal of water pollutants, which respond to an external magnet that is used to remove both pollutants and composite nanomaterial traces from water. They are environmentally friendly and effective adsorbents for water treatment. In this respect, a simple in situ preparation method was used to prepare cryogel powder composite based on Fe3O4.Cu2O.Fe3O4 nanomaterials. The ionic cryogel based on 2‐acrylamido‐2‐methylpropane sulfonate sodium salt and styrene sulfonate sodium salt was prepared by crosslinking polymerization at low temperature. The new magnetic nanoparticles based on Fe3O4.Cu2O.Fe3O4 were successfully prepared inside the cryogel networks by a simple reduction–coprecipitation method based on reaction of Fe3+ with sodium sulfite and Cu2+ in the presence of hydroxylamine and ammonia solution. The thermal stability, accurate Fe3O4.Cu2O.Fe3O4 content, magnetic properties, crystal lattice structure, particle sizes and morphology of the prepared cryogel composite were evaluated. The optimum conditions such as pH, contact time, adsorbate concentrations, adsorption equilibrium and adsorption kinetics were investigated to determine the efficiency of the prepared composite as an adsorbent to remove toxic methylene blue (MB) pollutant from aqueous solution. The data for MB adsorption confirmed the high ability of the prepared composite to remove more than 4.696 mmol L−1 of MB from water during 6 min. The regeneration and reuse experiments showed excellent data for the synthesized new dye as an effective adsorbent for water treatment. © 2018 Society of Chemical Industry
Academic self‐attributions for success and failure in mathematics and school refusal
Authors: Gonzálvez Carolina , Sanmartín Ricardo , Vicent María , Inglés Cándido J. , Aparicio‐Flores M. Pilar , García‐Fernández José M.
Published: March 2018

The aim of this research is twofold: to analyze the mean differences scores in mathematic self‐attributions based on school refusal and to verify its predictive capability on high scores in school refusal. The Sydney Attribution Scale and the School Refusal Assessment Scale‐Revised were administered to 1078 Spanish students (50.8% boys) aged between 8 and 11 years (M = 9.63; SD = 1.12). School refusers based on negative affect or anxiety attributed their failures more to the lack of capacity and effort, whereas students searching for tangible reinforcements outside of the school were more likely to attribute their successes to capacity. In turn, academic attributions acted as both positive and negative predictors of high‐school refusal. Results are discussed considering more adaptive attributional styles.
Trapping system comparisons for and factors affecting populations of Drosophila suzukii and Zaprionus indianus in winter‐grown strawberry
Authors: Renkema Justin M , Iglesias Lindsy E , Bonneau Phanie , Liburd Oscar E
Published: March 2018

BACKGROUND

Drosophila suzukii (Matsumura) is a major fruit pest in temperate regions worldwide, but in subtropical Florida, winter‐grown strawberries have not been severely affected. Zaprionus indianus Gupta is another invasive drosophilid species and a pest of some tropical fruits. To improve monitoring, trapping systems for D. suzukii and Z. indianus were tested. Morphology, ovarian status and the suitability and availability of non‐crop hosts as possible D. suzukii population‐limiting factors were assessed.

RESULTS

Traps with commercial attractants captured more D. suzukii but fewer Z. indianus than those with a homemade mixture. In central and northern Florida, < 10% and 30‐80% of D. suzukii, respectively, exhibited darker, winter morph coloration, and 55‐75% of females from central Florida were carrying mature and/or immature eggs. Adult D. suzukii were reared from fruits of two of 28 potential hosts: elderberry (Sambucus nigra) and nightshade (Solanum americanum). Nightshade, but not elderberry, was common on field perimeters (21 and six of 36 fields, respectively). Traps placed in wooded or partially wooded field edges yielded the most D. suzukii.

CONCLUSION

Florida strawberry is at risk of D. suzukii infestation, as flies were captured throughout the growing season. However, fly captures remained relatively low, peaking at 1.5 flies per trap per day. In central Florida, the low availability and suitability of non‐crop hosts likely limit population growth. The finding of few flies in northern Florida may additionally be attributable to a greater proportion of flies displaying winter morph coloration than in central Florida. © 2018 Society of Chemical Industry
Remaining useful life prediction for hard failures using joint model with extended hazard
Authors: Man Jianing , Zhou Qiang
Published: March 2018

In this paper, we investigate a joint modeling method for hard failures where both degradation signals and time‐to‐event data are available. The mixed‐effects model is used to model degradation signals, and extended hazard model is used for the time‐to‐event data. The extended hazard is a general model which includes two well‐known hazard rate models, the Cox proportional hazards model and accelerated failure time model, as special cases. A two‐stage estimation approach is used to obtain model parameters, based on which remaining useful life for the in‐service unit can be predicted. The performance of the method is demonstrated through both simulation studies and a real case study.
Toward achieving Sustainable Development Goals in Ivory Coast: Simulating pathways to sustainable development
Authors: Pedercini Matteo , Zuellich Gunda , Dianati Kaveh , Arquitt Steven
Published: March 2018

With the adoption of the United Nations 2030 Agenda, countries face the challenge of implementing strategies to achieve sustainable development goals (SDGs). To support the Ivory Coast Government in this process, we have developed the Treshold21‐iSDG model, which integrates long‐term social, economic and environmental policy analyses for SDG attainment. Specifically, we assess the impact of the implementation of the National Prospective Study (NPS) on achievement of the 17 SDGs, and identify necessary strategic adjustments. We compare SDG attainment under three scenarios: business‐as‐usual, NPS, and an “SDG” scenario that includes adjustments for critical aspects of SDGs not sufficiently covered by the NPS. The analysis identifies cross‐sector impacts of policies and highlights the benefits of coordinated implementation of comprehensive and coherent SDG strategies. Such findings emphasize the importance of integrated simulation models to support planning of SDG strategies and to complement information provided by stakeholder engagement and other sector‐specific or qualitative tools.
Recent Trends in Nanomaterials‐Based Colorimetric Detection of Pathogenic Bacteria and Viruses
Authors: Choi Yoojin , Hwang Ji Hyeon , Lee Sang Yup
Published: March 2018

Rapid, sensitive, selective, convenient, and cost‐effective pathogen diagnosis is important to prevent further spread of pandemic diseases, minimize social and economic losses, and to facilitate right clinical therapy. Over the past few years, various sensor‐based diagnostic systems outperforming conventional pathogenic diagnostic assays have been developed. Among them, colorimetric biosensors detecting target molecules by the naked eye have attracted much attention due to their simplicity, practicality, and cost‐effectiveness. Recently, nanomaterials have been adopted as a versatile signal transduction and amplification tool for rapid and sensitive detection of pathogenic bacteria and viruses. Here, recent trends and advances are reviewed in detecting and diagnosing pathogenic bacteria and viruses using colorimetric biosensors employing various nanomaterials. In addition, it is discussed how nanomaterials and bioreceptors can be better integrated together to develop rapid and sensitive colorimetric detection system in the future.
A policy‐centric approach to protecting OS kernel from vulnerable LKMs
Authors: Tian Donghai , Xiong Xi , Hu Changzhen , Liu Peng
Published: March 2018

Loadable kernel modules (LKMs) that contain vulnerabilities are a big threat to modern operating systems (OSs). The primary reason is that there is no protection mechanism inside the kernel space when the LKM is executed. As a result, kernel module exploitation can seriously affect the OS kernel security. Although many protection systems have been developed to address this problem in the past few years, there still remain some challenges: (1) How to automatically generate a security policy before the kernel module is enforced? (2) How to properly mediate the interactions between the kernel module and the OS kernel without modifications on the existing OS, hardware, and kernel module structure? To address these challenges, we present LKM guard (LKMG), a policy‐centric system that can protect commodity OS kernel from vulnerable LKMs. Compared with previous systems, LKMG is able to generate a security policy from a kernel module and then enforce the policy during the run time. Generally, the working process of LKMG can be divided into 2 stages. First, we utilize static analysis to extract the kernel code and data access patterns from a kernel module's source code and then combine these patterns with the related memory address information to generate a security policy. Second, by leveraging the hardware‐assisted virtualization technology, LKMG isolates the kernel module from the rest of the kernel and then enforces the kernel module's execution to obey the derived policy. The experiments show that our system can defend against various attacks launched by the compromised kernel module effectively with moderate performance cost.
The Effect of Sulfur Concentration in the Metal on the Mass Transfer of Phosphorus in Bloated Metal Droplets
Authors: Gu Kezhuan , Dogan Neslihan , Coley Kenneth S.
Published: March 2018

In Basic Oxygen Steelmaking, metal droplets created by the impact of the oxygen jet will swell due to internal decarburization when they react with oxidizing slag in the emulsion zone. In this study, the dephosphorization behavior of bloated metal droplets containing different sulfur concentrations is investigated in the temperature range from 1813 to 1913 K using X‐ray fluoroscopy coupled with constant volume pressure change measurements and chemical analysis of quenched samples. The results show that higher sulfur droplets (>0.017 wt%) have a much longer incubation period for swelling than those with lower sulfur (<0.017 wt%). Due to this different swelling behavior, the dephosphorization rate for high sulfur droplets is found to be not heavily affected by the experimental temperature compared to the case of lower sulfur droplets. Employing a mixed control model including mass transfer and chemical reaction, the effect of temperature on dephosphorization kinetics is further discussed. The mass transfer coefficient in the metal, km, is found to increase slightly with increasing temperature for droplets with 0.021 wt% sulfur. It is also found that lower rates of CO formation result in less stirring in the droplet and lower mass transfer rates of phosphorus for high sulfur droplets.
Tailoring Functional Chitosan‐Based Composites for Food Applications
Authors: Nunes Cláudia , Coimbra Manuel A. , Ferreira Paula
Published: March 2018

Chitosan‐based functional materials are emerging for food applications. The covalent bonding of molecular entities demonstrates to enhance resistance to the typical acidity of food assigning mechanical and moisture/gas barrier properties. Moreover, the grafting to chitosan of some functional molecules, like phenolic compounds or essential oils, gives antioxidant, antimicrobial, among others properties to chitosan. The addition of nanofillers to chitosan and other biopolymers improves the already mentioned required properties for food applications and can attribute electrical conductivity and magnetic properties for active and intelligent packaging. Electrical conductivity is a required property for the processing of food at low temperature using electric fields or for sensors application.
Syntheses, Characterization, and Fluorescence Properties of Four Coordination Polymers based on Double Betaine Ligands
Authors: Gai Yanli , Zhao Xueyan , Chen Yan , Liang Bing , Li Xin , Guo Xinyue , Huang Qing , Liu Lijun , Xiong Kecai
Published: March 2018

Four novel In3+ and Cd2+ based 1D coordination compounds constructed by double betaine ligands were synthesized and characterized structurally and optically. They assemble into 3D supra‐molecular architectures via different stacking or entanglement of 1D zigzag shaped chains, in which C–H···Cl and C–H···O hydrogen bonding interactions play a dramatic impact. Compound 1 displays a 1D + 1D → 3D four‐connect lvt net with 42·84 topology. Compound 2 assembles into a 3D architecture by inclined stacking of the adjacent zigzag chains. Compound 3 displays a 2D + 2D → 3D inclined polycatenation based on the resulting 2D (6, 3) layers that constructed by 1D chains. Compound 4 displays a 3D supra‐molecular architecture based on 1D chains, which were connected via the hydrogen bonding. Meanwhile, four compounds emit in the range of visible region owing to the intra‐ligand π*→π and/or π*→n electron transition induced florescence.
Primary Stenting of the Superficial Femoral Artery in Patients with Intermittent Claudication Has Durable Effects on Health-Related Quality of Life at 24 Months: Results of a Randomized Controlled Trial
Authors: Lindgren Hans I. V. , Qvarfordt Peter , Bergman Stefan , Gottsäter Anders ,   The Swedish Endovascular Claudication Stenting Trialists, Jansson I. , Litterfeldt E. , Lindgren Hans I. V. , Qvarfordt Peter , Fransson T. , Öjersjö A. , Hilbertson A. , Röjlar T. , Gottsäter Anders , Gruber G. , Hörer T. , Larzon T. , Jonasson T. , Strandberg C. , Andersson P. , Bergman Stefan , Lundell L. , Svensson A. , Warvsten M.
Published: March 2018

Background

Intermittent claudication (IC) is commonly caused by lesions in the superficial femoral artery (SFA), yet invasive treatment is still controversial and longer term patient-reported outcomes are lacking. This prospective randomized trial assessed the 24-month impact of primary stenting with nitinol self-expanding stents compared to best medical treatment (BMT) alone in patients with stable IC due to SFA disease on health-related quality of life (HRQoL).

Methods

One hundred patients with stable IC due to SFA disease treated with BMT were randomized to either stent (n = 48) or control (n = 52) group. HRQoL assessed by Short Form 36 Health Survey (SF-36) and EuroQoL 5-dimensions (EQ5D) 24 months after treatment were primary outcome measures. Walking Impairment Questionnaire, ankle–brachial index (ABI), and walking distance were secondary outcomes.

Results

Significantly better SF-36 Physical Component Summary (P = 0.024) and physical domain scores such as Physical Function (P = 0.012), Bodily Pain (P = 0.002), General Health (P = 0.037), and EQ5D (P = 0.010) were reported in intergroup comparison between the stent and the control group. Both ABI (from 0.58 ± 0.11 to 0.85 ± 0.18; P < 0.001 in the stent group and from 0.63 ± 0.17 to 0.69 ± 0.18; P = 0.036 in the control group) and walking distance (from 170 ± 90 m to 616 ± 375 m; P < 0.001 in the stent group and from 209 ± 111 m to 331 ± 304 m; P = 0.006 in the control group) improved significantly in intragroup comparisons.

Conclusions

In patients with IC caused by lesions in the SFA, primary stenting compared to BMT alone was associated with significant improvements in HRQoL, ABI, and walking distance durable up to 24 months of follow-up.

Clinical Trial Registrationhttp://www.clinicaltrials.gov. Unique Identifier:
NCT01230229