bluuebunny/crossref_metadata_2025 huggingface dataset:
Fortified tuna bone powder supplementation increases bone mineral density of lactating rats and their offspring
Authors: Suntornsaratoon Panan , Charoenphandhu Narattaphol , Krishnamra Nateetip
Published: September 2017

BACKGROUND

Breastfeeding leads to bone calcium loss for milk production, resulting in progressive maternal osteopenia. Calcium supplement from natural sources has been postulated to be more beneficial to bone health than purified CaCO3 because natural sources also contain other nutrients such as certain amino acids that might enhance calcium metabolism. Herein, we examined the effect of calcium supplementation from tuna bone powder and CaCO3 on bones of dams and the offspring.

RESULTS

Both forms of calcium supplement, i.e. tuna bone powder and CaCO3, increased maternal bone mineral density (BMD). However, bone histomorphometry revealed that only tuna bone had beneficial effect on maternal bone microstructure, i.e. increased bone formation, decreased bone resorption and increased in bone volume. Regarding the mechanical properties, the decreased ultimate load in non‐supplement lactating mothers was restored to the load seen in nulliparous animals by calcium supplementation. Moreover, both tuna bone and CaCO3 supplementation in mothers led to increased milk calcium concentration and consequently increased BMD in the growing offspring.

CONCLUSION

Calcium supplement from tuna bone powder was effective in preventing maternal osteopenia. Tuna bone, which is a readily available fishing industrial waste, is a good alternative source of calcium supplement that increases BMD in both lactating mothers and the neonates. © 2017 Society of Chemical Industry
Distribution network management under electricity deregulation using evolutionary many‐objective optimization
Authors: Sekizaki Shinya , Nishizaki Ichiro , Hayashida Tomohiro
Published: September 2017

A distribution network operator can reconfigure the network topology by operating section switches to improve multiple objective functions, that is, the line losses and the lifespan of transformers. In the context of long term network management, the impact of future electricity deregulation should be taken into account. Because the related literature has not addressed the above problems, this paper presents a multicriteria optimization approach for efficient distribution network management under electricity market deregulation. The main contributions of this paper can be summarized as follows: (a) the time‐variable (time dependent) and nonconvex issues for the distribution network management are formulated such that the time series variations of the line losses and the transformers mechanical operations are modelled, (b) an electricity consumption model under the deregulation, in which consumers flexibly respond to electricity prices, is taken into account, and (c) from the practical viewpoint, the proposed evolutionary many‐objective optimization approach is applied to find approximated Pareto optimal solutions of the nonconvex large‐scale problem within practical operating time. It can be seen from the computational experiment that the proposed method enables the network operator to easily identify a better network topology, which adequately meets the multiple requirements of the operator.
Progression of MDS‐UPDRS Scores Over Five Years in De Novo Parkinson Disease from the Parkinson's Progression Markers Initiative Cohort
Authors: Holden Samantha K. , Finseth Taylor , Sillau Stefan H. , Berman Brian D.
Published: September 2017

Background

The Movement Disorder Society‐Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS‐UPDRS) is a commonly used tool to measure progression in patients with Parkinson's disease (PD). Longitudinal changes in MDS‐UPDRS scores in patients with de novo PD have not been established. The objective of this study was to determine progression rates of MDS‐UPDRS scores in de novo PD.

Methods

In total, 362 participants from the Parkinson's Progression Markers Initiative, a multicenter, longitudinal cohort study of de novo PD, were included. Longitudinal progression of MDS‐UPDRS total and subscale scores were modeled using mixed model regression.

Results

MDS‐UPDRS scores increased in a linear fashion over 5 years in patients with de novo PD. MDS‐UPDRS total scores increased an estimated 4.7 points per year, Part I scores increased 0.92 points per year, Part II scores increased 0.99 points per year, and Part III scores increased 2.4 points per year.

Conclusions

The expected average progression of MDS‐UPDRS scores in patients with de novo PD from this study can assist in clinical monitoring and provide comparative data for the detection of disease modification in treatment trials.
Cost efficiency of insurance firms in Ghana
Authors: Danquah Michael , Otoo David Mensah , Baah‐Nuakoh Amoah
Published: September 2017

The huge infrastructural deficit in Africa requires the establishment of an efficient insurance industry in the pursuance of economic development. Unfortunately, global statistics reveal low patronage of insurance in developing countries, thus making its impact limited in the region. To position the industry for economic development, this study utilizes the stochastic frontier technique to undertake a thorough analysis on the cost efficiency of insurers from the perspective of developing economies using Ghana as a case study. The results on the 30 insurers studied from 2005 to 2014 indicate that insurers in Ghana operate with about 53.8% average cost inefficiency. This stands to confirm the long existed low performance perception of Ghanaians about the industry. Factors identified to explain the cost inefficiencies were firm size, market share, capitalization, reinsurance, regulation, and business type. Several policy recommendations that can help boost the cost efficiency of insurers were derived from the results.
Quasi‐planar substrate integrated waveguide pyramidal horn antenna for Ku‐band applications
Authors: Ashraf Syed Ali , Singh Soni , Sahu Bhagirath , Singh S. P.
Published: September 2017

In this paper, a novel quasi‐planar substrate integrated waveguide (SIW) pyramidal horn antenna for Ku‐band applications is presented. The proposed antenna provides wider multiple frequency sub‐bands in Ku‐band and improved E‐plane half power beamwidth. Although the proposed design affects the planarity of the antenna to some extent but by and large it maintains the compactness of the antenna. In addition, the proposed horn is easy to fabricate and preserves two most important characteristics of SIW technology, namely compactness and easy manufacturing. Dimension optimization of the antenna and simulation studies of its input and radiation characteristics were performed using Ansys HFSS software. Further, a prototype of the proposed antenna was fabricated on FR4 substrate of dimensions 35 mm × 35 mm × 3.2 mm and antenna characteristics were determined experimentally. It is found that simulated antenna characteristics are nearly in agreement with the corresponding experimental ones, which verify the proposed antenna concept.
Design of inverse Class‐F power amplifier based on dual transmission line with 87.4% drain efficiency
Authors: Huang Hang , Zhang Bo , Yu Cuiping , Gao Jinchun , Wu Yongle , Liu Yuanan
Published: September 2017

In this paper, an inverse Class‐F power amplifier (PA) based on dual transmission line (DTL) is presented. The output matching network (OMN) with DTL has a simple and compact circuit topology compared with other harmonic‐tuned OMNs with open/short shunt stubs and provides up to 6th harmonic suppression. In addition, the DTL structure is equivalent to a quarter wavelength transformer for fundamental matching. A GaN HEMT is adopted to achieve high output power and high drain efficiency in the proposed inverse Class‐F PA. Finally, a 2.4 GHz inverse Class‐F PA is designed and fabricated. The experimental results show the highest drain efficiency of 87.4% in the operating frequency with the corresponding output power of 44.5 dBm, and adjacent channel power ratio (ACPR) of −50.8/‐51.6 dBc with digital predistortion technique (DPD) at 2.4 GHz.
A phase correction technique based on spatial movements of antennas in real‐time for designing self‐adapting conformal array antennas
Authors: Roy Sayan , Sajal Sayeed , Braaten Benjamin D.
Published: September 2017

This article presents a real‐time adaptive phase correction technique for flexible phased array antennas on conformal surfaces of variable shapes. Previously reported pattern correctional methods for flexible phased array antennas require prior knowledge on the possible non‐planar shapes in which the array may adapt for conformal applications. For the first time, this initial requirement of shape curvature knowledge is no longer needed and the instantaneous information on the relative location of array elements is used here for developing a geometrical model based on a set of Bézier curves. Specifically, by using an array of inclinometer sensors and an adaptive phase‐correctional algorithm, it has been shown that the proposed geometrical model can successfully predict different conformal orientations of a 1‐by‐4 array antenna in real‐time without the requirement of knowing the shape‐changing characteristics of the surface the array is attached upon. Moreover, the phase correction technique is validated by determining the field patterns and broadside gain of the 1‐by‐4 array antenna on 4 different conformal surfaces with multiple points of curvatures. Throughout this work, measurements are shown to agree with the analytical solutions and full‐wave simulations.
Three‐dimensional‐printed tapered cavity‐backed flush‐mountable wideband antenna for UAV
Authors: Lee Seongkyu , Jeoung Guho , Choi Jaehoon
Published: September 2017

A 3D‐printed tapered cavity‐backed flush‐mountable wideband antenna for UAV applications is proposed. The antenna consists of a mono‐cone and an exponentially tapered cavity, which are fabricated using 3D printing technology. Performance degradation caused by the resonance of a conventional cavity is reduced by tapering the cavity. The antenna has the overall dimensions of 224 mm × 224 mm × 34 mm. The measured 10‐dB return loss bandwidth of the antenna is 24.4 GHz ranging from 1.3 GHz to 25.7 GHz (180%). The measured radiation pattern has an omnidirectional characteristic over the operating frequency band.
Adjustable compact dual‐band microstrip bandpass filter using T‐shaped resonators
Authors: Khani Shiva , Makki Seyed Vahab AL‐Din , Mousavi Seyed Mohammad Hadi , Danaie Mohammad , Rezaei Pejman
Published: September 2017

In this letter, a compact dual‐band bandpass filter (BPF) is designed, analyzed, and fabricated. A loop resonator loaded by two modified T‐shaped resonators, double T‐shaped resonators, and open bended stubs are applied to form the proposed configuration. The coupling spaces between the loop resonators and open bended stubs result in two passbands with the center frequencies of 2.4 GHz and 5.7 GHz. The LC equivalent circuit of the main resonator is introduced to present an analytical description. Without needing to increase the circuit size, the upper passband can be adjusted between 5.72 GHz and 6.93 GHz. The measured data indicates less than 0.64 dB and 0.76 dB insertion losses in the first and second passbands, respectively. Adjustable second center frequency, compact size, low insertion loss, good suppression level, and a symmetrical structure are the marked features of the proposed BPF. Finally, a good agreement between the simulated and measured results is observed.
A novel dual‐band tunable band‐notched antenna
Authors: Xi Lei , Zhai Huiqing , Zang Yiping , Li Long
Published: September 2017

This letter presents a novel dual‐band tunable band‐notched antenna. The antenna consists of a monopole ultrawideband (UWB) antenna and two kinds of novel notched structures. A tunable notched wave is obtained by adjusting the capacitance on the notched structure. Monopole antenna works well on 3.1‐10.6 GHz. The low frequency notched wave can be adjusted on the 3–4 GHz, and the high frequency band notched wave can be adjusted on the 5–6 GHz, which can avoid the influence of the WiMax and WLAN narrowband communication system on the UWB communication system, and improve the performance of the antenna system. At the same time, through the analysis of the surface current distribution of the notched antenna, the principle of the notched wave is studied. At last, a prototype of the band‐notched antenna is fabricated and measured whose simulation is consistent with the measurement.
Thermally tunable fano resonance of a conductive rubber‐based metamaterial
Authors: Qiu Kepeng , Liu Zijun
Published: September 2017

This article presents a thermally tunable Fano resonator obtained by asymmetrically coupling a conductive rubber‐based H‐shaped split ring resonator (SRR) and a copper C‐shaped SRR coated on a Teflon fiberglass slab substrate. Thermal tunability of the Fano resonance is provided by the temperature‐sensitive resistance property of the conductive rubber. The thermal tunability of the Fano resonance obtained from the proposed resonator structure is demonstrated by both simulation and experimental results. This study provides a novel tunable approach for designing dynamical electromagnetic modulation devices.
Cross‐range target response analysis for extreme high‐squint synthetic aperture radar
Authors: Burfeindt Matthew J.
Published: September 2017

We propose a formulation for predicting the cross‐range characteristics of the synthetic aperture radar (SAR) point‐spread function (PSF) for extremely high squints based on the concept of phased array factors. We demonstrate the validity of this approach by comparing theoretical predictions to PSF dimensions extracted from SAR images. The results show that the proposed approach is more robust than the conventional theory for extreme high‐squint scenarios.
A bandwidth enhancement for metamaterial microstrip antenna
Authors: Wu Wenjing , Yuan Bo , Guan Boran , Xiang Tieming
Published: September 2017

A bandwidth enhancement for metamaterial microstrip antenna is presented for ultra‐wideband (UWB) applications. The metamaterial antenna consists of irregular figures etched on the upper patch periodically and a planar metallic ground carved by grid patterned gaps on the bottom patch. The overall dimension of the proposed antenna is
mm3. Experimental results show that the relative impedance bandwidth (–10 dB) of the proposed antenna is 168.3% with the ranging from 2.9 to 33.7 GHz, whose relative bandwidth is improved by 38.9–121.9% than the previously reported wideband ones. Its simulated reflection coefficient has a good agreement with the measured one, and its gain varies from 1.30 to 7.17 dB, meanwhile, it has a maximum radiation efficiency of 95.6% in the operating frequency band. Besides, the end‐fire directional radiation in the high frequency band is observed. Thus, the proposed antenna could be a potential candidate for UWB wireless communication systems.
Asynchronously coupled resonant junctions for diplexers and multiport filtering networks
Authors: Ogbodo Eugene A. , Wu Yun , Callaghan Peter , Wang Yi
Published: September 2017

This article proposes the use of asynchronously coupled resonator junctions in the design of diplexers. This is to ease the control and implementation of the external couplings at the common port of an all‐resonator‐based diplexer. A comparison study has been performed between a conventional diplexer and the proposed diplexer. To further explore the possibilities of the proposed junction technique, a four‐port multiport filtering networks was proposed and designed to function as a double diplexer. Good agreements have been achieved between the measurements of the prototype devices and the simulations.
A novel homogeneous stacked yttrium ion garnet resonator antenna for wideband application
Authors: Othman Mohamadariff , Wan Ali Wan Fahmin Faiz , Ahmad Zubir Ihsan , Ain Mohd Fadzil , Ahmad Zainal Arifin
Published: September 2017

The intent of this study is to realize efficient wideband DRA using unbiased low permittivity yttrium ion garnet (YIG) with excess Fe2O3. The fabricated YIG resonators with the same dimension but different ɛr are used together to produce wideband stacked YIG resonator antenna (YRA). Three stacked YIG resonators with excess Fe2O3 of 8% (YR8), 14% (YR14), and 17% (YR17) present the best YIG resonator combinations with bandwidth of 24.22%. Findings also indicate broadband radiation pattern throughout the design frequency range. The simulated and measured results are all in agreement. In conclusion, this work offers an improved and efficient YRA using YIG resonator with excess Fe2O3.
A novel very wideband integrated antenna system for 4G and 5G mm‐wave applications
Authors: Ikram M. , Sharawi M. S. , Shamim A.
Published: September 2017

In this work, a novel very wideband 4‐element monopole based multiple‐input multiple‐output (MIMO) antenna system with single connected antenna array (CAA) is presented. The CAA is based on a single slot which is etched on the ground plane. A 2 × 1 power divider/combiner is used to excite the slot to act as a CAA. The proposed design covers the 4G bands between 1850 and 3700, and the 28 GHz 5G band. The covered bandwidths are 1462 and 240 MHz from 1843 to 3305 MHz and 3500 to 3740 MHz, respectively, for 4G applications. A bandwidth of 1.22 GHz from 27.5 to 28.72 GHz is obtained for 5G applications. The proposed antenna system is designed on a double layer RO4350B substrate with height of 0.76 mm and dielectric constant of 3.5. The total size of the design is 115 × 65 × 0.76 mm3. It is compact, low profile and suitable for wireless handheld devices. The MIMO performance metrics such as isolation and ECC are evaluated and good agreement between simulations and measurements is achieved.
A miniaturized dual‐band microstrip patch antenna using a symmetrical composite right/left handed unit
Authors: Zhang Chaoqun , Gong Jianqiang , Wang Yuhao
Published: September 2017

In this article, a miniaturized dual‐band microstrip patch antenna is proposed, which is in essence a composite right/left handed unit with symmetrical slots and metallic pins. An effective design procedure is presented. The ratio of the higher center frequency to the lower one can be varied from 1.01 to 1.59 by adjusting specified parameters. A typical model has been fabricated and measured to validate the design concept. The model shows a dual‐frequency function and patch‐like radiations at 7.1 GHz for n = −1 mode and at 8.42 GHz for n = 0 mode respectively, both providing wide coverage angles in half space.
A 2–22 GHz CMOS wideband distributed power amplifier
Authors: Zhang Ying , Ma Kaixue
Published: September 2017

This article presents a novel wideband distributed power amplifier (DPA) implemented in a 0.18 μm CMOS technology. The DPA consists of a preamplifier and a medium‐power power amplifier (PA), and both of them are respectively composed of two distributed amplifiers (DAs), which have separate input artificial transmission lines (ATLs) but with their output ATLs shared to achieve wide frequency band. In the medium‐power PA, the large‐signal multigated transistor technology is applied to further improve the linear output power. Measurement results show that the DPA achieves 10.2 dB average associated gain from 2.5 to 22 GHz. The output power at 1‐dB output compression point (OP1dB) is more than 8 dBm over the frequency of 2–22 GHz, and the peak OP1dB is 12.6 dBm with the power‐added efficiency of 7.2% at 6 GHz.
Linear variable filter enabling an enhanced wavelength gradient based on shadow‐mask sputtering
Authors: Ji Peng , Gao Song , Park Chul‐Soon , Lee Sang‐Shin , Choi Duk‐Yong
Published: September 2017

A linear variable filter (LVF) that improves the wavelength gradient is proposed, and a sample is manufactured using a radio frequency sputtering technique with the help of a vertical shadow mask, which simplifies the fabrication process. The LVF is based on a metal‐dielectric‐metal Fabry–Perot etalon, wherein the dielectric cavity is tapered in thickness along the device so that the resonance wavelength can be continuously tuned at various positions. The produced device shows a filtering range from 443 nm to 602 nm over a distance of 16 mm, which corresponds to a wavelength gradient of 10 nm/mm. The measured spectra exhibited, on average, a peak transmission of 39% and a spectral bandwidth of 46 nm.
A bandwidth and gain enhancement for microstrip antenna based on metamaterial
Authors: Yuan Bo , Zheng Yan He , Zhang Xiao Hong , You Bin , Luo Guo Qing
Published: September 2017

An ameliorated ultrawide band (UWB) and high‐gain microstrip antenna based on planar metamaterial is presented and discussed in this paper. The proposed antenna with a compact size of 32 × 28 × 0.794 mm3 has mesh‐shaped patch and patterned ground plane with crossed strip gaps. By means of novel planar metamaterial structure, impedance bandwidth and gain own a significant improvement. The simulations show that the antenna has a super‐wide band (less than −10 dB), from 3.06 GHz to 36.4 GHz, covering the entire UWB frequency band (from 3.1 GHz to 10.6 GHz) set by FCC. Within the operating band of concern, the antenna gain can reach as high as 8.02 dB. Due to the surface wave coming from the patterned patch and ground plane, the antenna presents end‐fire directional radiation in the higher frequency region. To validate the simulation results, a prototype is fabricated and measured. And the measured results are in good agreement with the simulation results. It is obvious that advantages mentioned above will enable the proposed antenna to be well applied in the short‐range wireless communication system.
Experimental characterization of the impedance of balanced UHF RFID tag antennas
Authors: Stoumpos C. K. , Anagnostou D. E. , Chryssomallis M. T.
Published: September 2017

An experimental procedure for the accurate characterization of the impedance of balanced tag antennas for RFID applications is reintroduced. The balanced devices that are characterized are modeledas 2‐port networks and their impedance is derived from network parameters, through a rarely used equation that is preferred because it accounts for the losses of non‐reciprocal structures such as imperfect test fixtures or baluns. The measurements are conducted using a test fixture for the proper excitation of the balanced devices, and its effects are removed by shifting the measurement plane to the plane of the device under test. The accuracy of the proposed method is demonstrated through the measurement of the impedance of a balanced dipole antenna, and is complemented by the measurement of the RFID ASIC chip. The experimental characterization of the impedance of an RFID tag antenna constitutes a secure way to achieve conjugate matching between the 2 devices (ie, the antenna and the RFID chip), and finally enhance the reading range of the RFID tags. Also, since RFID tags are designed to be placed directly on different surfaces, the proposed procedure is further evaluated by mounting the antenna onto 2 more surfaces.
A cryogenic measurement setup for characterization microwave devices
Authors: Rybalko Oleksandr
Published: September 2017

A cryogenic measurement setup for characterization microwave devices from room to cryogenic temperatures is presented. The setup allows testing microwave devices at variable temperatures ranging from 300 to 77 K. Frequency doubler (94/188 GHz) has been cooled to 77 K and peak efficiency of 32% at an input‐power level of 207 mW is achieved. For verification experimental results the millimeter‐wave GaAs Schottky barrier diode model is developed for CAD simulator. The simulated peak efficiency is 37% at 77 K. The estimation of simulated and measured data of the doubler efficiency versus temperature has the same trend from 77 to 300 K which confirmed the cryogenic measurement setup applicability.
Circularly polarized 2‐arm spiral antenna for 60‐GHz applications
Authors: Zhu Jianfeng , Liao Shaowei , Li Shufang
Published: September 2017

A wideband circularly polarized (CP) 2‐arm spiral antenna is designed for 60‐GHz applications in this letter. The proposed antenna is implemented on a single layer with spiral printed on the top surface of the substrate and fed in a differential way through 2 metallized via holes. Unidirectional radiation is achieved thanks to the presence of the ground plane, which is placed with a distance of one‐quarter of the guided wavelength to the spiral. A cavity is mounted on the top of the spiral antenna to suppress the surface wave propagate along the substrate as well as to improve the antenna gain. Experimental results show that the prototype achieves the −10‐dB impedance bandwidth from 55.2 to 66 GHz with circular polarization. The peak gain at boresight is 9.5 dBi occurring at 63 GHz and the radiation patterns are stable over the operating frequency band.
Ultrawide isolation bandwidth compensated power divider for UWB applications
Authors: Uchendu Iyemeh E. , Kelly James R.
Published: September 2017

This article presents design analyses for achieving an ultrawide isolation bandwidth compensated power divider (CPD). The CPD offers improvement in complexity, size, and insertion when compared with alternative techniques for increasing isolation bandwidth. A prototype CPD with −15 dB isolation bandwidth of 114% was fabricated and measured to validate the analyses.
Frequency independent 180° phase shifter based on UWB coupled sections
Authors: Tebache Soufiane , Ghanem Farid , Belouchrani Adel , Mansoul Ali
Published: September 2017

In this article, a novel Ultra‐Wideband (UWB) 180° planar phase shifter is designed and fabricated. The proposed design is mainly based on coupled sections which are realized by inserting slots into the common ground plane of the multilayer circuit. Two identical structures, leading to discard parameters that disturb the output phase shift, are introduced in the design. To get 180° phase difference shift, via holes are used to perform a short circuit in one of the two coupled sections. Theoretical analysis based on four port network is presented to explain the characteristics of the proposed design. Further, experimental measurements are performed and compared with simulation results to validate the proposed approach. Hence, a good simulated to measured agreement is obtained.
Design and fabrication of a small‐form transmitter optical subassembly for 100 Gbps short reach optical interconnect
Authors: Liu Fengman , He Huimin , Xue Haiyun , Song Mangu , Dai Fengwei , Sun Yu , Wu Peng , Cao Liqiang
Published: September 2017

A high‐coupling‐efficiency and convenient‐integration transmitter optical subassembly for 25 Gbps small‐form transceiver is developed in this paper. In the structure, the VCSEL is vertically mounted on the silicon substrate by the flip‐chip method to enable direct and passive alignment with the fibers plugging in the fiber guide holes on the silicon substrate. By the optical simulation, the maximum coupling efficiency of VCSEL is −0.38 dB. The vertical electrical pads of the VCSEL are connected to the horizontal wire‐bonding pads on silicon substrate by the 90°‐bend GS micro strip lines. Thus, the interconnection between the transmitter optical subassembly and the electrical PCB board is conveniently realized by the low‐cost wire‐bonding method. The electrical performance of the 90°‐bend GS micro strip lines on the optical subassembly is also evaluated by the 3D electromagnetic simulation. In order to verify the transmission performance of the transmitter optical subassembly, it is integrated with an electrical board using bonding wires, and then the optical performance of the transmitter is measured. By the measurement, the optical subassembly can operate up to 25 Gbps per channel.
Procedure to measure real time latency using software defined radio in a W‐band fiber‐wireless link
Authors: Rico‐Martínez Mónica , Morales Alvaro , Mehmeri Victor , Puerta Rafael , Varón Margarita , Monroy Idelfonso Tafur
Published: September 2017

Reducing latency is a major challenge for current telecommunications systems. 5G networks are envisioned to achieve end‐to‐end latencies below 1 ms, thus enabling the Internet of Things (IoT) evolution and new applications such as Tactile Internet. In this article, we present a new procedure to measure real time latency in hybrid optical‐wireless links. We obtained 2 ms end to end latency using Software Defined Radio to measure latency in a physical setup. We tested the procedure on W‐band fiber‐wireless link and validated the results against PING over GRE tunnel.
Improved quantitative 90Y bremsstrahlung SPECT/CT reconstruction with Monte Carlo scatter modeling
Authors: Dewaraja Yuni K. , Chun Se Young , Srinivasa Ravi N. , Kaza Ravi K. , Cuneo Kyle C. , Majdalany Bill S. , Novelli Paula M. , Ljungberg Michael , Fessler Jeffrey A.
Published: September 2017

Purpose

In 90Y microsphere radioembolization (RE), accurate post‐therapy imaging‐based dosimetry is important for establishing absorbed dose versus outcome relationships for developing future treatment planning strategies. Additionally, accurately assessing microsphere distributions is important because of concerns for unexpected activity deposition outside the liver. Quantitative 90Y imaging by either SPECT or PET is challenging. In 90Y SPECT model based methods are necessary for scatter correction because energy window‐based methods are not feasible with the continuous bremsstrahlung energy spectrum. The objective of this work was to implement and evaluate a scatter estimation method for accurate 90Y bremsstrahlung SPECT/CT imaging.

Methods

Since a fully Monte Carlo (MC) approach to 90Y SPECT reconstruction is computationally very demanding, in the present study the scatter estimate generated by a MC simulator was combined with an analytical projector in the 3D OS‐EM reconstruction model. A single window (105 to 195‐keV) was used for both the acquisition and the projector modeling. A liver/lung torso phantom with intrahepatic lesions and low‐uptake extrahepatic objects was imaged to evaluate SPECT/CT reconstruction without and with scatter correction. Clinical application was demonstrated by applying the reconstruction approach to five patients treated with RE to determine lesion and normal liver activity concentrations using a (liver) relative calibration.

Results

There was convergence of the scatter estimate after just two updates, greatly reducing computational requirements. In the phantom study, compared with reconstruction without scatter correction, with MC scatter modeling there was substantial improvement in activity recovery in intrahepatic lesions (from > 55% to > 86%), normal liver (from 113% to 104%), and lungs (from 227% to 104%) with only a small degradation in noise (13% vs. 17%). Similarly, with scatter modeling contrast improved substantially both visually and in terms of a detectability index, which was especially relevant for the low uptake extrahepatic objects. The trends observed for the phantom were also seen in the patient studies where lesion activity concentrations and lesion‐to‐liver concentration ratios were lower for SPECT without scatter correction compared with reconstruction with just two MC scatter updates: in eleven lesions the mean uptake was 4.9 vs. 7.1 MBq/mL (P = 0.0547), the mean normal liver uptake was 1.6 vs. 1.5 MBq/mL (P = 0.056) and the mean lesion‐to‐liver uptake ratio was 2.7 vs. 4.3 (P = 0.0402) for reconstruction without and with scatter correction respectively.

Conclusions

Quantitative accuracy of 90Y bremsstrahlung imaging can be substantially improved with MC scatter modeling without significant degradation in image noise or intensive computational requirements.
Simultaneous detection of glutathione and lactate using spectral editing at 3 T
Authors: Chan Kimberly L. , Snoussi Karim , Edden Richard A.E. , Barker Peter B.
Published: September 2017

Two spectral editing techniques for the simultaneous detection of glutathione (GSH) and lactate (Lac) in the human brain at 3 T are described and evaluated. These methods, ‘sMEGA’ (sinc‐MEscher and GArwood) and ‘DEW’ (Double Editing With), were optimized to detect GSH and Lac simultaneously at 3 T using density‐matrix simulations and validation in phantoms. Simulations to test for co‐edited metabolites within the detected GSH region of the spectrum were also performed. In vivo data were acquired in the midline parietal region of seven subjects using both methods, and compared with conventional MEGA‐PRESS (MEscher and GArwood‐Point RESolved Spectroscopy) acquisitions of GSH and Lac. Simulations and phantom experiments showed that sMEGA and DEW had a high editing efficiency for both GSH and Lac. In the phantom, the editing efficiency of GSH was >88% relative to a conventional GSH MEGA‐PRESS acquisition, whereas, for Lac, the editing efficiency was >95% relative to a conventional Lac MEGA‐PRESS acquisition. Simulations also showed that the editing efficiency of both methods was comparable with separate MEGA‐PRESS acquisitions of the same metabolites. In addition, simulations and in vivo spectra showed that, at a TE of 140 ms, there was a partial overlap between creatine (Cr) and GSH peaks, and that N‐acetyl aspartate/N‐acetyl aspartyl glutamate (NAA/NAAG) were sufficiently resolved from GSH. In vivo measurements showed that both sMEGA and DEW edited GSH and Lac reliably with the same editing efficiency as conventional MEGA‐PRESS acquisitions of the same metabolites, with measured GSH integrals of 2.23 ± 0.51, 2.31 ± 0.38, 2.38 ± 0.53 and measured Lac integrals of 1.72 ± 0.67, 1.55 ± 0.35 and 1.53 ± 0.54 for MEGA‐PRESS, DEW and sMEGA, respectively. Simultaneous detection of GSH and Lac using sMEGA and DEW is possible at 3 T with high editing efficiency.
Engine oil based generalized brinkman‐type nano‐liquid with molybdenum disulphide nanoparticles of spherical shape: Atangana‐Baleanu fractional model
Authors: Jan Syed Aftab Alam , Ali Farhad , Sheikh Nadeem Ahmad , Khan Ilyas , Saqib Muhammad , Gohar Madeha
Published: September 2017

The impact of magnetic field on Engine Oil based generalized Brinkman‐type nanofluid over an oscillating vertical plate embedded in a porous medium is studied. Molybdenum Disulphide (MoS2) nanoparticles of spherical shape are suspended in Engine Oil, taken as conventional base fluid. Effect of thermal radiation in energy equation is also considered. A generalized model of Brinkman‐type fluid is considered with newly introduced fractional derivatives known as Atangana‐Baleanu Derivative (ABD) in the presence of heat transfer due to convection. Exact solution of the problem is determined by means of the Laplace transform. Expressions for velocity and temperature are obtained in terms of Mittag‐Leffler and General Wright function. The effects of various pertinent parameters on velocity are portrayed and discussed graphically. Numerical results of rate of heat transfer are computed in tabular form. Which showed that increasing values of volume fraction and Prandtl number increase rate of heat transfer.
Analysis of clonal expansions through the normal and premalignant human breast epithelium reveals the presence of luminal stem cells
Authors: Cereser Biancastella , Jansen Marnix , Austin Emily , Elia George , McFarlane Taneisha , van Deurzen Carolien HM , Sieuwerts Anieta M , Daidone Maria G , Tadrous Paul J , Wright Nicholas A , Jones Louise , McDonald Stuart AC
Published: September 2017

It is widely accepted that the cell of origin of breast cancer is the adult mammary epithelial stem cell; however, demonstrating the presence and location of tissue stem cells in the human breast has proved difficult. Furthermore, we do not know the clonal architecture of the normal and premalignant mammary epithelium or its cellular hierarchy. Here, we use deficiency in the mitochondrial enzyme cytochrome c oxidase (CCO), typically caused by somatic mutations in the mitochondrial genome, as a means to perform lineage tracing in the human mammary epithelium. PCR sequencing of laser‐capture microdissected cells in combination with immunohistochemistry for markers of lineage differentiation was performed to determine the clonal nature of the mammary epithelium. We have shown that in the normal human breast, clonal expansions (defined here by areas of CCO deficiency) are typically uncommon and of limited size, but can occur at any site within the adult mammary epithelium. The presence of a stem cell population was shown by demonstrating multi‐lineage differentiation within CCO‐deficient areas. Interestingly, we observed infrequent CCO deficiency that was restricted to luminal cells, suggesting that niche succession, and by inference stem cell location, is located within the luminal layer. CCO‐deficient areas appeared large within areas of ductal carcinoma in situ, suggesting that the rate of clonal expansion was altered in the premalignant lesion. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Thickness dependence of ac electrical conductivity and dielectric behavior of plasma polymerized 1, 1, 3, 3–tetramethoxypropane thin films
Authors: Afroze Tamanna , Bhuiyan A.H.
Published: September 2017

AC electrical conductivity (σac), dielectric constant (ɛ′), and dielectric loss tangent (tan δ) of plasma polymerized 1, 1, 3, 3‐tetramethoxy‐propane (PPTMP) thin films of thicknesses 100, 150, and 200 nm prepared by plasma polymerization technique using a capacitively coupled glow discharge reactor have been investigated in the frequency range of 30–106 Hz. It is observed that σac increases as frequency increases with a higher slope in the medium frequency (<105Hz) region in the PPTMP thin films of three thicknesses. These observations suggest that the conduction may be dominated by hopping of carriers between the localized states. The general trend of ɛ′ is to increase with increasing thickness, ɛ′ remains independent of frequency upto about 104Hz and then falls rapidly. The dependence of tanδ with frequency for PPTMP thin films of different thicknesses showed small relaxation peak at the very low frequencies (<102Hz) and then it decreases slightly with a broad minimum at 103 Hz and again increases. Cole–Cole plot reveals that Debye type of mechanism is operative in the experimental frequency range. POLYM. ENG. SCI., 58:1342–1345, 2018. © 2017 Society of Plastics Engineers
Blue luminescent amorphous carbon nanoparticles synthesized by microplasma processing of folic acid
Authors: Wang Qingyang , Zhang Qing , Chen Yanfei , He Jie , Jiang Kai , Hu Zhigao , Zhong Xiaoxia
Published: September 2017

Environmentally friendly synthesis of carbon nanoprticles (C‐NPs) from folic acid (FA) is realized with the assistance of microplasma. TEM shows that the synthesized FA C‐NPs are amorphous and of diameter around 47 nm. The produced FA C‐NPs exhibit an excitation independent emission around 445 nm with the fluorescence quantum yield 13% at excitation wavelength of 370 nm. X‐ray photoelectron spectroscopy (XPS) shows the FA C‐NPs are composed of carbon (64.15%), nitrogen (6.04%), and oxygen (29.81%). Raman spectroscopy shows that the intensity ratio between the sp3and sp2hybridizations of Carbon is 0.35. UV‐Vis absorption, Fourier Transform Infrared Spectroscopy (FTIR), and Nuclear Magnetic Resonance (NMR) spectra provide a deep insight into the fluorescence of FA C‐NPs. With plasma processing of FA, carbon atoms are involved in sp2hybridization and amine (NH2), NH and COOH groups are converted into ROOCNHCOOR group. As a consequence, the electron donating ability of aromatic ring is enhanced, which plays an important role in the fluorescence of FA C‐NPs. Finally, the promising application of FA C‐NPs in bioimaging is also demonstrated by fluorescence labeling of MCF‐7 cancer cells.
Noninvasive airway approaches for acute neuromuscular respiratory failure in emergency departments
Authors: Chen Tai‐Heng , Hsu Jong‐Hau , Jong Yuh‐Jyh
Published: September 2017

Emerging evidence advocates for noninvasive ventilation (NIV) combined with mechanical in‐exsufflation (MIE) as a first‐line approach for acute respiratory failure (ARF) in patients with neuromuscular disorders (NMD). To date, most NIV studies of ARF in NMD patients have been performed in intensive care units or in hospital settings. However, the utility of using combined NIV/MIE in the emergency department (ED) settings is unclear. We report on the implementation of NIV/MIE in two children with type II spinal muscular atrophy who presented to the ED with ARF. This is the first report on the feasibility and efficacy of combining NIV/MIE in ED settings for pediatric NMD patients with ARF.
Respiratory outcomes after initial hospital discharge in children with ventricular shunts and bronchopulmonary dysplasia
Authors: McGrath‐Morrow Sharon A. , Ahn Edward S. , Collaco Joseph M.
Published: September 2017

Introduction

Children born premature who require ventricular shunt placement for post hemorrhagic hydrocephalus are at increased risk for neurodevelopmental delay. We hypothesized that preterm infants with bronchopulmonary dysplasia (BPD) who require ventricular shunt (VS) placement are at additive risk for long‐term respiratory morbidities due to their higher likelihood of neurodevelopmental delay. We also hypothesized that children with BPD and ventricular shunts would require frequent shunt revisions during early childhood following initial shunt placement.

Methods

All subjects were recruited from the Johns Hopkins Bronchopulmonary Dysplasia Clinic between January 2008 and November 2016. A review of demographic and clinical information was undertaken and a respiratory outcomes questionnaire was completed by the primary caregiver.

Results

Fifty‐five (8.9%) of 623 subjects in the study population had ventricular shunts, with a mean 4.6 ± 2.3 years of follow‐up data (range: 0.5‐10.1). Subjects with VS were more likely to be born at earlier gestational ages and be discharged on supplemental oxygen compared to BPD subjects alone. Outpatient respiratory symptoms and acute care usage were similar between the two groups. BPD subjects with VS were more likely to have had gastric tubes placed. A total of 270 neurosurgical procedures were performed in subjects with VS with a mean of 4.9 ± 5.4 procedures/subject.

Conclusion

Children with ventricular shunts and BPD had similar outpatient respiratory outcomes compared to children with BPD alone; however respiratory morbidities may have been mitigated by the greater use of gastric tubes in the VS + BPD group. Multiple neurosurgical procedures were common in children with ventricular shunts.
Radiative Pulling Forces, Exerted by Evanescent Fields Along a Hyperbolic Metamaterial Slab
Authors: Nefedov Igor , Shalin Alexander S.
Published: September 2017

We show and investigate in detail the optical pulling forces acting on a particle in the vicinity of a waveguiding structure made of a hyperbolic metamaterial. We have shown analytically that if the waveguide dispersion is negative, the longitudinal radiative force outside of hyperbolic metamaterial is always a pulling force, that is directed toward the source of electromagnetic energy flow in contrast to the common situation when a strong propulsion force emerges near the surface of an open waveguide.
Stark Resonances Induced by the Exchange–Correlation Potential in Piezoelectric Nanowires
Authors: Wołoszyn Maciej , Spisak Bartłomiej J.
Published: September 2017

Self‐consistent Schrödinger–Poisson scheme is used to analyze the electronic transport in GaN/AlGaN nanowires containing a double‐barrier structure within the Landauer formalism. Results of the calculations indicate that the exchange–correlation potential leads to emergence of Stark resonances in the transport window. The shot noise characterizing the current fluctuations reveals sub‐Poissonian characteristics, significantly modified by the exchange–correlation contribution. As a consequence, we determine how geometric and material parameters affect those phenomena, which can be used to optimize the operation of such devices.
Second‐order elastic constants of hexagonal hydroxylapatite (P63) fromab initioquantum mechanics: Comparison between DFT functionals and basis sets
Authors: Ulian Gianfranco , Valdrè Giovanni
Published: September 2017

Three very popular Hamiltonians in the density functional theory framework, PBE, PBEsol, and B3LYP, and different basis sets (Gaussian‐type orbitals and plane waves) were employed to simulate the hydroxylapatite unit cell and its second‐order elastic constants. Dispersive interactions were included in the quantum‐mechanical treatment via the DFT‐D2 and Tkatchenko‐Scheffler schemes. The calculated bulk, shear, and Young's moduli were in the range of 82‐117 GPa, 42‐51 GPa, and 107‐134 GPa, respectively. The axial moduli,KaandKb, were instead in the range of 277‐322 GPa and 506‐509 GPa. The theoretical data, especially those from plan waves simulations, are in good agreement with available results in literature and further extend the knowledge of the mechanical and vibrational properties of hydroxylapatite.
The effect of rivers, streams, and canals on property values
Authors: Nicholls S. , Crompton J. L.
Published: September 2017

Rivers, streams, and canals support a variety of critical agricultural, industrial, transportation, ecological, and household uses. They also provide important aesthetic, recreational, and sociocultural benefits. This review paper synthesizes the evidence to date regarding the value of these linear water features as aesthetic and recreational resources to adjacent and nearby residents. Specifically, it summarizes 25 studies that have used the hedonic pricing method to calculate the effects of views of and proximity to rivers, streams, and canals on surrounding residential property values. The majority of studies indicated that significant positive property price effects are associated with river, stream, and canal view and proximity, though these effects appear less definitive in rural than urban settings. Implications of the body of evidence for planning, management, and development are discussed, and potential effects of climate change and diversion policies are highlighted. Improvements in measurement facilitated by advanced geographic information systems and rigorous spatially explicit regression techniques are noted.
A Facile and Versatile Electrochemical Tuning of Graphene for Oxygen Reduction Reaction in Acidic, Neutral and Alkali media
Authors: Manju Venkatesan , Rao Vusa Chiranjeevi Srinivasa , Arumugam Palaniappan , Berchmans Sheela
Published: September 2017

The need for the development of metal‐free electrocatalysts for oxygen reduction reaction (ORR) has become a necessity to circumvent the prohibitive cost of Pt and the shortcomings of Pt‐based catalysts. Herein, for the first time, graphene surface was tuned by a simple, room temperature, and easily adaptable electrochemical approach using ammonium carbamate as a nitrogen precursor. This method efficiently tuned the graphene surface by incorporating nitrogen and nitrogen functionalities with an unprecedented content of nitrogen (22.48%). The surface tuned graphene (N−Gr) acts as an efficient metal‐free electrocatalyst towards oxygen reduction reaction in a wide pH range, i. e. from neutral (pH 7) to alkaline (pH 14). Also, the N−Gr exhibits a similar Tafel slope (76 mV/dec) to that of Pt/C (64 mV/dec) in 0.1 M KOH. Long term stability and better tolerance to fuel are the other advantages of the N−Gr. The observed ORR activity of the N−Gr might be due to the higher content of nitrogen which provides higher active sites to promote electron transfer in ORR. All these confirm that the surface tuned graphene can be a suitable electrocatalyst for fuel cell applications and the electrochemical approach may pave a way to develop a set of novel and efficient electrocatalysts using the other graphitic nanocarbons.