bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell-Free Demineralized Bone Matrix for Mesenchymal Stem Cells Survival and Colonization
Authors: Mattioli-Belmonte Monica , Montemurro Francesca , Licini Caterina , Iezzi Iolanda , Dicarlo Manuela , Cerqueni Giorgia , Coro Florinda , Vozzi Giovanni
Published: April 2019

Decellularized bone matrix is receiving much attention as biological scaffolds and implantable biomaterials for bone tissue regeneration. Here, we evaluated the efficacy of a cell-free demineralized bone matrix on mesenchymal stem cells (MSCs) survival and differentiation in vitro. The seeding of human umbilical cord-derived MSCs (hUC-SCs) on decellularized bone matrices up to 14 days was exploited, assessing their capability of scaffold colonization and evaluating gene expression of bone markers. Light and Scanning Electron Microscopies were used. The obtained cell-free decalcified structures showed elastic moduli attributable to both topology and biochemical composition. Morphological observation evidenced an almost complete colonization of the scaffolds after 14 days of culture. Moreover, in hUC-SCs cultured on decalcified scaffolds, without the addition of any osteoinductive media, there was an upregulation of Collagen Type I (COL1) and osteonectin (ON) gene expression, especially on day 14. Modifications in the expression of genes engaged in stemness were also detected. In conclusion, the proposed decellularized bone matrix can induce the in vitro hUC-SCs differentiation and has the potential to be tested for in in vivo tissue regeneration.
Effect of Stacking Sequence and Sodium Bicarbonate Treatment on Quasi-Static and Dynamic Mechanical Properties of Flax/Jute Epoxy-Based Composites
Authors: Fiore Vincenzo , Calabrese Luigi
Published: April 2019

The present paper deals with the investigation of quasi-static and dynamic mechanical response of epoxy-based composites reinforced with flax and/or jute plain weave fabrics. In order to evaluate the influence of the stacking sequence, two monolithic laminates reinforced with flax or jute fibers and two hybrid flax/jute laminates were manufactured through the vacuum infusion technique. Furthermore, an eco-friendly and cost-effective surface treatment based on fiber soaking in a sodium bicarbonate solution was employed to improve the fiber-matrix adhesion. The mechanical characterization (by means of quasi-static flexural, dynamic mechanical thermal analysis and Charpy impact tests) allowed to evidence that the sodium bicarbonate treatment leads to noticeable improvement of the mechanical performances of flax reinforced composites, whereas jute composites experience a slight decrease of their mechanical properties. Overall, the hybridization allows to achieve intermediate mechanical properties among those of monolithic composites. Furthermore, the coupled action of hybridization and surface treatment does not lead to a beneficial and reliable effect on the mechanical response of the resulting composites.
Optimization of Intrinsic ZnO Thickness in Cu(In,Ga)Se2-Based Thin Film Solar Cells
Authors: Alhammadi Salh , Park Hyeonwook , Kim Woo Kyoung
Published: April 2019

The typical structure of high efficiency Cu(InGa)Se2 (CIGS)-based thin film solar cells is substrate/Mo/CIGS/CdS/i-ZnO/ZnO:Al(AZO) where the sun light comes through the transparent conducting oxide (i.e., i-ZnO/AZO) side. In this study, the thickness of an intrinsic zinc oxide (i-ZnO) layer was optimized by considering the surface roughness of CIGS light absorbers. The i-ZnO layers with different thicknesses from 30 to 170 nm were deposited via sputtering. The optical properties, microstructures, and morphologies of the i-ZnO thin films with different thicknesses were characterized, and their effects on the CIGS solar cell device properties were explored. Two types of CIGS absorbers prepared by three-stage co-evaporation and two-step sulfurization after the selenization (SAS) processes showed a difference in the preferred crystal orientation, morphology, and surface roughness. During the subsequent post-processing for the fabrication of the glass/Mo/CIGS/CdS/i-ZnO/AZO device, the change in the i-ZnO thickness influenced the performance of the CIGS devices. For the three-stage co-evaporated CIGS cell, the increase in the thickness of the i-ZnO layer from 30 to 90 nm improved the shunt resistance (RSH), open circuit voltage, and fill factor (FF), as well as the conversion efficiency (10.1% to 11.8%). A further increas of the i-ZnO thickness to 170 nm, deteriorated the device performance parameters, which suggests that 90 nm is close to the optimum thickness of i-ZnO. Conversely, the device with a two-step SAS processed CIGS absorber showed smaller values of the overall RSH (130–371 Ω cm2) than that of the device with a three-stage co-evaporated CIGS absorber (530–1127 Ω cm2) ranging from 30 nm to 170 nm of i-ZnO thickness. Therefore, the value of the shunt resistance was monotonically increased with the i-ZnO thickness ranging from 30 to 170 nm, which improved the FF and conversion efficiency (6.96% to 8.87%).
Generalized Viscosity Implicit Iterative Process for Asymptotically Non-Expansive Mappings in Banach Spaces
Authors: Pan Chanjuan , Wang Yuanheng
Published: April 2019

In this paper, we propose a generalized viscosity implicit iterative method for asymptotically non-expansive mappings in Banach spaces. The strong convergence theorem of this algorithm is proved, which solves the variational inequality problem. Moreover, we provide some applications to zero-point problems and equilibrium problems. Further, a numerical example is given to illustrate our convergence analysis. The results generalize and improve corresponding results in the literature.
Cutting Convex Polytopes by Hyperplanes
Authors: Hibi Takayuki , Li Nan
Published: April 2019

Cutting a polytope is a very natural way to produce new classes of interesting polytopes. Moreover, it has been very enlightening to explore which algebraic and combinatorial properties of the original polytope are hereditary to its subpolytopes obtained by a cut. In this work, we devote our attention to all the separating hyperplanes for some given polytope (integral and convex) and study the existence and classification of such hyperplanes. We prove the existence of separating hyperplanes for the order and chain polytopes for any finite posets that are not a single chain, and prove there are no such hyperplanes for any Birkhoff polytopes. Moreover, we give a complete separating hyperplane classification for the unit cube and its subpolytopes obtained by one cut, together with some partial classification results for order and chain polytopes.
The Optimality Region for a Single-Machine Scheduling Problem with Bounded Durations of the Jobs and the Total Completion Time Objective
Authors: Sotskov Yuri N. , Egorova Natalja G.
Published: April 2019

We study a single-machine scheduling problem to minimize the total completion time of the given set of jobs, which have to be processed without job preemptions. The lower and upper bounds on the job duration is the only information that is available before scheduling. Exact values of the job durations remain unknown until the completion of the jobs. We use the optimality region for the job permutation as an optimality measure of the optimal schedule. We investigate properties of the optimality region and derive O ( n ) -algorithm for calculating a quasi-perimeter of the optimality set (i.e., the sum of lengths of the optimality segments for n given jobs). We develop a fast algorithm for finding a job permutation having the largest quasi-perimeter of the optimality set. The computational results in constructing such permutations show that they are close to the optimal ones, which can be constructed for the factual durations of all given jobs.
Effects of Polyunsaturated Fatty Acids on Nonspecific Typical Dry Eye Disease: A Systematic Review and Meta-Analysis of Randomized Clinical Trials
Authors: Chi Sheng-Chu , Tuan Hsin-I , Kang Yi-No
Published: April 2019

To investigate the effects of polyunsaturated fatty acids (PUFAs) in patients with dry eye disease (DED), a multifactorial inflammatory disorder, we searched Cochrane Library, EMBASE, PubMed, and Web of Science for randomized clinical trials (RCTs) investigating the effect of PUFAs in patients with DED before March 2019. Two reviewers independently abstracted data of tear breakup time (TBUT), Schirmer’s test, osmolarity, and ocular surface disease index (OSDI). We conducted pairwise meta-analysis using means and standard deviations (SDs) in a random-effects model for continuous outcomes. Thirteen eligible RCTs with 1782 patients with nonspecific typical DED were included. Patients who received PUFA treatment without other eye medications exhibited greater improvements in TBUT (MD = 1.80; p = 0.001), Schirmer test scores (MD = 0.50; p < 0.001), osmolarity (MD = −15.95; p < 0.001), and OSDI scores (MD = −10.19; p < 0.001) than those who received placebo treatment. However, the effects of PUFAs on TBUT (p < 0.001) and OSDI scores (p = 0.03) weakened with treatment duration. PUFAs are effective in treating nonspecific typical DED, particularly as a short-term treatment, with relatively few adverse events. Therefore, in real-world clinical practice, PUFA supplements are worth being suggested to patients with nonspecific typical DED who are not concurrently using other topical or systematic eye medications.
Protective Effects of Omega-3 Fatty Acids in Cancer-Related Complications
Authors: Freitas Raquel , Campos Maria M.
Published: April 2019

Omega-3 polyunsaturated fatty acids (PUFAs) are considered immunonutrients and are commonly used in the nutritional therapy of cancer patients due to their ample biological effects. Omega-3 PUFAs play essential roles in cell signaling and in the cell structure and fluidity of membranes. They participate in the resolution of inflammation and have anti-inflammatory and antinociceptive effects. Additionally, they can act as agonists of G protein-coupled receptors, namely, GPR40/FFA1 and GPR120/FFA4. Cancer patients undergo complications, such as anorexia-cachexia syndrome, pain, depression, and paraneoplastic syndromes. Interestingly, the 2017 European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines for cancer patients only discuss the use of omega-3 PUFAs for cancer-cachexia treatment, leaving aside other cancer-related complications that could potentially be managed by omega-3 PUFA supplementation. This critical review aimed to discuss the effects and the possible underlying mechanisms of omega-3 PUFA supplementation in cancer-related complications. Data compilation in this critical review indicates that further investigation is still required to assess the factual benefits of omega-3 PUFA supplementation in cancer-associated illnesses. Nevertheless, preclinical evidence reveals that omega-3 PUFAs and their metabolites might modulate pivotal pathways underlying complications secondary to cancer, indicating that this is a promising field of knowledge to be explored.
The Association of Life’s Simple 7 with Aldosterone among African Americans in the Jackson Heart Study
Authors: Kesireddy Veena , Tan Yubo , Kline David , Brock Guy , Odei James B. , Kluwe Bjorn , Effoe Valery S. , Echouffo Tcheugui Justin B. , Kalyani Rita R. , Sims Mario , Taylor Herman A. , Mongraw-Chaffin Morgana , Akhabue Ehimare , Joseph Joshua J.
Published: April 2019

Background: Among African Americans (AAs), attaining higher levels of American Heart Association (AHA) ideal cardiovascular health (Life’s Simple 7 [LS7]) is associated with lower risk of diabetes and cardiovascular disease (CVD). We previously showed that aldosterone is associated with higher risk of diabetes and CVD in AAs. Thus, we investigated the association of LS7 metrics with aldosterone in the Jackson Heart Study (JHS). Methods: Ideal metrics were defined by AHA 2020 goals for health behaviors (smoking, dietary intake, physical activity, and body mass index) and health factors (total cholesterol, blood pressure, and fasting glucose). The number of ideal LS7 metrics attained at baseline were summed into a continuous score (0–7) and categorical groups (Poor: 0–1, Intermediate: 2–3, and Ideal: ≥4 ideal LS7 metrics). Multivariable linear regression was used. Results: Among 4,095 JHS participants (mean age 55 ± 13 years, 65% female), median serum aldosterone was 4.90, 4.30, and 3.70 ng/dL in the poor (n = 1132), intermediate (n = 2288) and ideal (n = 675) categories respectively. Aldosterone was 15% [0.85 (0.80, 0.90)] and 33% [0.67 (0.61, 0.75)] lower in the intermediate and ideal LS7 categories compared to the poor LS7 category. Each additional LS7 metric attained on continuous LS7 score (0–7) was associated with an 11% [0.89 (0.86, 0.91)] lower aldosterone level with variation by sex with women having a 15% lower aldosterone vs. 5% in men. Conclusions: Higher attainment of ideal LS7 metrics was associated with lower serum aldosterone among AAs with a greater magnitude of association among women compared to men.
Nutritional Outcome in Home Gastrostomy-Fed Children with Chronic Diseases
Authors: Martínez-Costa Cecilia , Calderón Caterina , Gómez-López Lilianne , Borraz Soraya , Crehuá-Gaudiza Elena , Pedrón-Giner Consuelo
Published: April 2019

The aim of the study was to assess the anthropometric outcomes after gastrostomy tube (GT) placement in children with chronic diseases and the influence of primary diagnosis, age, and nutritional support. A longitudinal, multicenter, and prospective study was performed evaluating 65 children with GT feeding and chronic diseases (61.5% with neurological disease). Each child was evaluated three times (at baseline and at 6 and 12 months after GT placement) and the following data was collected: primary diagnosis, age at GT placement, anthropometry, and feeding regime. Repeated measures ANOVA were used to analyze the main effects (intra and intergroup) and the interactions effects on weight gain and linear growth at 6 and 12 months after GT placement. All patients significantly improved their body mass index (BMI)-for-age z-score (p < 0.001) and height-for-age z-score (p < 0.05) after 6 and 12-month of follow-up. BMI gain increased significantly the first 6 months, followed by a plateau, while height followed a linear trend. Children with GT placement before 18 months old experienced an accelerated growth rate during the first 6 months post-GT. This technique showed the effectiveness of GT placement improving nutritional status and growth catch up regardless of their primary diagnosis and the type of nutritional support.
Melanocortin-4 Receptor and Lipocalin 2 Gene Variants in Spanish Children with Abdominal Obesity: Effects on BMI-SDS after a Lifestyle Intervention
Authors: Morell-Azanza Lydia , Ojeda-Rodríguez Ana , Giuranna Johanna , Azcona-SanJulián Mª Cristina , Hebebrand Johannes , Marti Amelia , Hinney Anke
Published: April 2019

Mutations leading to a reduced function of the melanocortin-4 receptor (MC4R) exert a major gene effect on extreme obesity. Recently it was shown that the bone derived hormone lipocalin 2 (LCN2) binds to the MC4R and activates a MC4R dependent anorexigenic pathway. We identified mutations in both genes and screened the effects of MC4R and LCN2 mutations on eating behavior and weight change after a lifestyle intervention. One hundred and twelve children (11.24 ± 2.6 years, BMI-SDS 2.91 ± 1.07) with abdominal obesity participated in a lifestyle intervention. MC4R and LCN2 coding regions were screened by Sanger sequencing. Eating behavior was assessed at baseline with the Children Eating Behavior Questionnaire (CEBQ). We detected three previously described non-synonymous MC4R variants (Glu42Lys, Thr150Ile, and Arg305Gln) and one non-synonymous polymorphism (Ile251Leu). Regarding LCN2, one known non-synonymous variant (Thr124Met) was detected. Eating behavior was described in carriers of the MC4R and LCN2 mutation and in non-carriers. MC4R and LCN2 mutations were detected in 2.42% and 0.84%, respectively, of Spanish children with abdominal obesity. A number of subjects with functional mutation variants in MC4R and LCN2 were able to achieve a reduction in BMI-SDS after a lifestyle intervention.
Pterostilbene Reduces Liver Steatosis and Modifies Hepatic Fatty Acid Profile in Obese Rats
Authors: Aguirre Leixuri , Palacios-Ortega Sara , Fernández-Quintela Alfredo , Hijona Elizabeth , Bujanda Luis , Portillo María P.
Published: April 2019

Excessive fat accumulation within the liver is known as “simple hepatic steatosis”, which is the most benign form of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to determine whether pterostilbene improves this hepatic alteration in Zucker (fa/fa) rats. Animals were distributed in two experimental groups (n = 10) and fed a standard laboratory diet. Rats in the pterostilbene group were given a dose of 30 mg/kg body weight/d for six weeks. After sacrifice, serum glucose, transaminase, and insulin concentrations were quantified and the liver triacylglycerol content and fatty acid profile was analyzed. Different pathways of triacylglycerol metabolism in liver were studied, including fatty acid synthesis and oxidation, triglyceride assembly, fatty acid uptake, and glucose uptake. With pterostilbene administration, a reduction in insulin concentrations (consequently in the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)) and hepatic triacylglycerol content were observed. No effects were observed in pterostilbene-treated rats in the activity of de novo lipogenesis enzymes. An improvement in the fatty acid profile was observed in pterostilbene-treated rats. In conclusion, pterostilbene is a useful molecule to reduce liver steatosis. Its delipidating effect is due, at least in part, to reduced fatty acid availability and triacylglycerol synthesis, as well as to an increased very low-density lipoprotein assembly and fatty acid oxidation.
Preliminary Automated Determination of Edibility of Alternative Foods: Non-Targeted Screening for Toxins in Red Maple Leaf Concentrate
Authors: Pearce Joshua M. , Khaksari Maryam , Denkenberger David
Published: April 2019

Alternative food supplies could maintain humanity despite sun-blocking global catastrophic risks (GCRs) that eliminate conventional agriculture. A promising alternative food is making leaf concentrate. However, the edibility of tree leaves is largely uncertain. To overcome this challenge, this study provides the methods for obtaining rapid toxics screening of common leaf concentrates. The investigation begins with a non-targeted approach using an ultra-high-resolution hybrid ion trap orbitrap mass spectrometer with electrospray ionization (ESI) coupled to an ultra-high pressure two-dimensional liquid chromatograph system on the most common North American leaf: the red maple. Identified chemicals from this non-targeted approach are then cross-referenced with the OpenFoodTox database to identify toxic chemicals. Identified toxins are then screened for formula validation and evaluated for risk as a food. The results after screening show that red maple leaf concentrate contains at least eight toxic chemicals, which upon analysis do not present substantial risks unless consumed in abundance. This indicates that red maple leaf is still a potential alternative food. The results are discussed in the context of expanding the analysis with open science and using leaf extract from other plants that are not traditionally used as foods to offset current global hunger challenges, and move to a more sustainable food system while also preparing for GCRs.
TiO2-Doped Electrospun Nanofibrous Membrane for Photocatalytic Water Treatment
Authors: Blanco Miren , Monteserín Cristina , Angulo Adrián , Pérez-Márquez Ana , Maudes Jon , Murillo Nieves , Aranzabe Estíbaliz , Ruiz-Rubio Leire , Vilas Jose Luis
Published: April 2019

This work has been focused on the one-step fabrication by electrospinning of polyamide 6 (PA6) nanofibre membranes modified with titanium dioxide nanoparticles (TiO2), where these TiO2 nanoparticles aggregates could induce a photocatalytic activity. The main potential application of these membranes could be the purification of contaminated water. Thus, it is important to analyse the contaminant degradation capability since in these membranes this is based on their photocatalytic activity. In this work, the effect of the photocatalysis has been studied both on the degradation of an organic model contaminant and on the removal of Escherichia coli and other coliform bacteria. As a result, it was observed that these membranes present excellent photocatalytic activity when they are irradiated under UV light, allowing a 70% reduction of an organic model pollutant after 240 min. In addition, these membranes successfully removed Escherichia coli and other coliform bacteria in artificially inoculated water after 24 h of contact with them. Moreover, the stand-alone structure of the membranes allowed for the reusing of the immobilized catalyst. The experimental evidence indicated that developed nanofibre membranes are a fast and efficient solution for polluted water decontamination based on photocatalysis. Their use could contribute to guarantee a fresh water level and quality, mitigating the water scarcity problem worldwide.
Power Transmission Congestion Management Based on Quasi-Dynamic Thermal Rating
Authors: Wang Yanling , Sun Zidan , Yan Zhijie , Liang Likai , Song Fan , Niu Zhiqiang
Published: April 2019

Transmission congestion not only increases the operation risk, but also reduces the operation efficiency of power systems. Applying a quasi-dynamic thermal rating (QDR) to the transmission congestion alarm system can effectively alleviate transmission congestion. In this paper, according to the heat balance equation under the IEEE standard, a calculation method of QDR is proposed based on the threshold of meteorological parameters under 95% confidence level, which is determined by statistical analysis of seven-year meteorological data in Weihai, China. The QDR of transmission lines is calculated at different time scales. A transmission congestion management model based on QDR is established, and the transmission congestion alarm system including conductor temperature judgment is proposed. The case shows that transmission congestion management based on QDR is feasible, which improves the service life and operation flexibility of the power grid in emergencies and avoids power supply shortages caused by unnecessary trip protection.
Tutorial Review on Space Manipulators for Space Debris Mitigation
Authors: Ellery Alex
Published: April 2019

Space-based manipulators have traditionally been tasked with robotic on-orbit servicing or assembly functions, but active debris removal has become a more urgent application. We present a much-needed tutorial review of many of the robotics aspects of active debris removal informed by activities in on-orbit servicing. We begin with a cursory review of on-orbit servicing manipulators followed by a short review on the space debris problem. Following brief consideration of the time delay problems in teleoperation, the meat of the paper explores the field of space robotics regarding the kinematics, dynamics and control of manipulators mounted onto spacecraft. The core of the issue concerns the spacecraft mounting which reacts in response to the motion of the manipulator. We favour the implementation of spacecraft attitude stabilisation to ease some of the computational issues that will become critical as increasing level of autonomy are implemented. We review issues concerned with physical manipulation and the problem of multiple arm operations. We conclude that space robotics is well-developed and sufficiently mature to tackling tasks such as active debris removal.
Application of an Array of Metal-Oxide Semiconductor Gas Sensors in an Assistant Personal Robot for Early Gas Leak Detection
Authors: Palacín Jordi , Martínez David , Clotet Eduard , Pallejà Tomàs , Burgués Javier , Fonollosa Jordi , Pardo Antonio , Marco Santiago
Published: April 2019

This paper proposes the application of a low-cost gas sensor array in an assistant personal robot (APR) in order to extend the capabilities of the mobile robot as an early gas leak detector for safety purposes. The gas sensor array is composed of 16 low-cost metal-oxide (MOX) gas sensors, which are continuously in operation. The mobile robot was modified to keep the gas sensor array always switched on, even in the case of battery recharge. The gas sensor array provides 16 individual gas measurements and one output that is a cumulative summary of all measurements, used as an overall indicator of a gas concentration change. The results of preliminary experiments were used to train a partial least squares discriminant analysis (PLS-DA) classifier with air, ethanol, and acetone as output classes. Then, the mobile robot gas leak detection capabilities were experimentally evaluated in a public facility, by forcing the evaporation of (1) ethanol, (2) acetone, and (3) ethanol and acetone at different locations. The positive results obtained in different operation conditions over the course of one month confirmed the early detection capabilities of the proposed mobile system. For example, the APR was able to detect a gas leak produced inside a closed room from the external corridor due to small leakages under the door induced by the forced ventilation system of the building.
Damage Identification in Various Types of Composite Plates Using Guided Waves Excited by a Piezoelectric Transducer and Measured by a Laser Vibrometer
Authors: Radzieński Maciej , Kudela Paweł , Marzani Alessandro , De Marchi Luca , Ostachowicz Wiesław
Published: April 2019

Composite materials are widely used in the industry, and the interest of this material is growing rapidly, due to its light weight, strength and various other desired mechanical properties. However, composite materials are prone to production defects and other defects originated during exploitation, which may jeopardize the safety of such a structure. Thus, non-destructive evaluation methods that are material-independent and suitable for a wide range of defects identification are needed. In this paper, a technique for damage characterization in composite plates is proposed. In the presented non-destructive testing method, guided waves are excited by a piezoelectric transducer, attached to tested specimens, and measured by a scanning laser Doppler vibrometer in a dense grid of points. By means of signal processing, irregularities in wavefield images caused by any material defects are extracted and used for damage characterization. The effectiveness of the proposed technique is validated on four different composite panels: Carbon fiber-reinforced polymer, glass fiber-reinforced polymer, composite reinforced by randomly-oriented short glass fibers and aluminum-honeycomb core sandwich composite. Obtained results confirm its versatility and efficacy in damage characterization in various types of composite plates.
Feature Extraction and Reconstruction by Using 2D-VMD Based on Carrier-Free UWB Radar Application in Human Motion Recognition
Authors: Jiang Liubing , Zhou Xiaolong , Che Li , Rong Shuwei , Wen Hexin
Published: April 2019

As the size of the radar hardware platform becomes smaller and smaller, the cost becomes lower and lower. The application of indoor radar-based human motion recognition has become a reality, which can be realized in a low-cost device with simple architecture. Compared with narrow-band radar (such as continuous wave radar, etc.), the human motion echo signal of the carrier-free ultra-wideband (UWB) radar contains more abundant characteristic information of human motion, which is helpful for identifying different types of human motion. In this paper, a novel feature extraction method by two-dimensional variational mode decomposition (2D-VMD) algorithm is proposed. And it is used for extracting the primary features of human motion. The 2D-VMD algorithm is an adaptive non-recursive multiscale decomposition method for nonlinear and nonstationary signals. Firstly, the original 2D radar echo signals are decomposed by the 2D-VMD algorithm to capture several 2D intrinsic mode function (BIMFs) which represent different groups of central frequency components of a certain type of human motion. Secondly, original echo signals are reconstructed according to the several BIMFs, which not only have a certain inhibitory effect on the clutter in the echo signal, but can also further demonstrate that the BIMFs obtained by the 2D-VMD algorithm can represent the original 2D echo signal well. Finally, based on the measured ten different types of UWB radar human motion 2D echo analysis signals, the characteristics of these different types of human motion are extracted and the original echo signal are reconstructed. Then, the three indicators of the PCC, UQI, and PSNR between the original echo signals and extraction/reconstruction 2D signals are analyzed, which illustrate the effectiveness of 2D-VMD algorithm to extract feature of human motion 2D echo signals of the carrier-free UWB radar. Experimental results show that BIMFs by 2D-VMD algorithm can well represent the echo signal characteristics of this type of human motion, which is a very effective tool for human motion radar echo signal feature extraction.
An Enhanced Multiplication of RF Energy Harvesting Efficiency Using Relay Resonator for Food Monitoring
Authors: Cao Xuan-Tu , Chung Wan-Young
Published: April 2019

Recently, radio frequency (RF) energy harvesting (RFEH) has become a promising technology for a battery-less sensor module. The ambient RF radiation from the available sources is captured by receiver antennas and converted to electrical energy, which is used to supply smart sensor modules. In this paper, an enhanced method to improve the efficiency of the RFEH system using strongly coupled electromagnetic resonance technology was proposed. A relay resonator was added between the reader and tag antennas to improve the wireless power transmission efficiency to the sensor module. The design of the relay resonator was based on the resonant technique and near-field magnetic coupling concept to improve the communication distance and the power supply for a sensor module. It was designed such that the self-resonant frequencies of the reader antenna, tag antenna, and the relay resonator are synchronous at the HF frequency (13.56MHz). The proposed method was analyzed using Thevenin equivalent circuit, simulated and experimental validated to evaluate its performance. The experimental results showed that the proposed harvesting method is able to generate a great higher power up to 10 times than that provided by conventional harvesting methods without a relay resonator. Moreover, as an empirical feasibility test of the proposed RF energy harvesting device, a smart sensor module which is placed inside a meat box was developed. It was utilized to collect vital data, including temperature, relative humidity and gas concentration, to monitor the freshness of meat. Overall, by exploiting relay resonator, the proposed smart sensor tag could continuously monitor meat freshness without any batteries at the innovative maximum distance of approximately 50 cm.
New Parameters Extracted from Tilted Fiber Bragg Grating Spectra for the Determination of the Refractive Index and Cut-Off Wavelength
Authors: Cięszczyk Sławomir , Kisała Piotr , Mroczka Janusz
Published: April 2019

Tilted fiber Bragg grating (TFBG) is a very popular fiber optic element that is used as a sensor for various physical quantities. The calculation of the refractive index of a substance surrounding the TFBG is based on its spectrum demodulation, which consists of determining a certain parameter that is correlated with the sought quantity. The most commonly used parameter is the area created by the maxima and minima of the cladding mode resonances. In this article, we propose a new group of methods, which are based on calculating the parameters related to the spectrum differences between the local average values in the range of occurrence of the cladding modes. The basic parameter used in this group of methods is the mean absolute deviation from the local mean, which is characterized by the best linearity among the considered group of methods. The calculated parameters, in their cumulative form, can also be used to determine the cut-off wavelength, which can also indirectly indicate the refractive index value. The proposed approaches were compared, in terms of measurement resolution, to the most commonly used methods, such as the cladding modes’ envelope area and the spectral contour lengths.
A Lagrange-Newton Method for EIT/UT Dual-Modality Image Reconstruction
Authors: Liang Guanghui , Ren Shangjie , Zhao Shu , Dong Feng
Published: April 2019

An image reconstruction method is proposed based on Lagrange-Newton method for electrical impedance tomography (EIT) and ultrasound tomography (UT) dual-modality imaging. Since the change in conductivity distribution is usually accompanied with the change in acoustic impedance distribution, the reconstruction targets of EIT and UT are unified to the conductivity difference using the same mesh model. Some background medium distribution information obtained from ultrasound transmission and reflection measurements can be used to construct a hard constraint about the conductivity difference distribution. Then, the EIT/UT dual-modality inverse problem is constructed by an equality constraint equation, and the Lagrange multiplier method combining Newton-Raphson iteration is used to solve the EIT/UT dual-modality inverse problem. The numerical and experimental results show that the proposed dual-modality image reconstruction method has a better performance than the single-modality EIT method and is more robust to the measurement noise.
A Unified Multiple-Target Positioning Framework for Intelligent Connected Vehicles
Authors: Xiao Zhongyang , Yang Diange , Wen Fuxi , Jiang Kun
Published: April 2019

Future intelligent transport systems depend on the accurate positioning of multiple targets in the road scene, including vehicles and all other moving or static elements. The existing self-positioning capability of individual vehicles remains insufficient. Also, bottlenecks in developing on-board perception systems stymie further improvements in the precision and integrity of positioning targets. Vehicle-to-everything (V2X) communication, which is fast becoming a standard component of intelligent and connected vehicles, renders new sources of information such as dynamically updated high-definition (HD) maps accessible. In this paper, we propose a unified theoretical framework for multiple-target positioning by fusing multi-source heterogeneous information from the on-board sensors and V2X technology of vehicles. Numerical and theoretical studies are conducted to evaluate the performance of the framework proposed. With a low-cost global navigation satellite system (GNSS) coupled with an initial navigation system (INS), on-board sensors, and a normally equipped HD map, the precision of multiple-target positioning attained can meet the requirements of high-level automated vehicles. Meanwhile, the integrity of target sensing is significantly improved by the sharing of sensor information and exploitation of map data. Furthermore, our framework is more adaptable to traffic scenarios when compared with state-of-the-art techniques.
Multiplexed Ultra-Sensitive Detection of Cr(III) and Cr(VI) Ion by FET Sensor Array in a Liquid Medium
Authors: Shahim Suman , Sukesan Revathi , Sarangadharan Indu , Wang Yu-Lin
Published: April 2019

Chromium, one of the top five toxic heavy metals ranked according to significance in public health by WHO, exists as Cr(III) which is naturally occurring or Cr(VI) which is anthropogenic in origin. The EPA specifies the maximum contaminant level in drinking water to be 10−6 M or 0.1 mg/L or 100 ppb for the total dissolved Cr. To ensure the water consumed by the population has these pollutants below the safe threshold, this report demonstrates a field effect transistor (FET) based sensor design incorporating a highly target specific ion-selective membrane combined with extended gate technology which manifests sensitivity exceeding the Nernst limit aided by the high field effect in the short gap region of extended gate technology. Characterization and repeated testing of the portable device revealed a commendable calibration sensitivity of 99 mV/log [Cr3+] and 71 mV/log [Cr6+] for Cr(III) and Cr(VI) respectively, well surpassing the Nernst limits of sensitivity and offering a detection limit lower than ion-selective electrodes (10−6 M), and comparable to the expensive benchtop laboratory instrument, ICP-MS. This report presents a robust, easy to fabricate, economic and efficient handheld biosensor to detect the chromium in a liquid sample whether it exists as Cr(III) or Cr(VI).
A Novel Tangential Electric-Field Sensor Based on Electric Dipole and Integrated Balun for the Near-Field Measurement Covering GPS Band
Authors: Wang Jianwei , Yan Zhaowen , Liu Wei , Su Donglin , Yan Xin
Published: April 2019

This paper presents a novel tangential electric-field sensor with an embedded integrated balun for sensing up a tangential electric field over a circuit surface in the near-field measurements covering the GPS band. The integrated balun is embedded into the sensor to transform the differential voltage induced by the electric dipole into the single output voltage. The measurement system with a high mechanical resolution for the characterizations and tests of the sensor is detailed in this paper. The frequency response of the sensor characterized by a microstrip line from 1.35 GHz to 1.85 GHz (covering the GPS band) is rather flat. The rejection to the magnetic field of the sensor is up to 20.1 dB. The applications and validations of the sensor are conducted through passive/active circuit measurements.
Acoustic Localization of Bragg Peak Proton Beams for Hadrontherapy Monitoring
Authors: Otero Jorge , Felis Ivan , Ardid Miguel , Herrero Alicia
Published: April 2019

Hadrontherapy makes it possible to deliver high doses of energy to cancerous tumors by using the large energy deposition in the Bragg-peak. However, uncertainties in the patient positioning and/or in the anatomical parameters can cause distortions in the calculation of the dose distribution. In order to maximize the effectiveness of heavy particle treatments, an accurate monitoring system of the deposited dose depending on the energy, beam time, and spot size is necessary. The localized deposition of this energy leads to the generation of a thermoacoustic pulse that can be detected using acoustic technologies. This article presents different experimental and simulation studies of the acoustic localization of thermoacoustic pulses captured with a set of sensors around the sample. In addition, numerical simulations have been done where thermo-acoustic pulses are emitted for the specific case of a proton beam of 100 MeV.
Motorcycle Drivers’ Parking Lot Choice Behaviors in Developing Countries: Analysis to Identify Influence Factors
Authors: Hoang Phuc Hai , Zhao Shengchuan , Houn Siv Eng
Published: April 2019

Drivers’ behaviors to look for a parking space are affected by numerous influence factors, and there are differences between motorcycle drivers and other drivers, such as car drivers and truck drivers. In many developing countries, motorcycles dominate urban transportation, and it is essential to assess the impact of motorcycle drivers’ parking choice behavior as a solution to reduce the effect on traffic flow. This study identified the influence factors of motorcycle drivers’ parking lot choice models in a developing country, Viet Nam. Data were collected in a motorcycle dependent city, Ho Chi Minh (HCM) City, typically. A stated preference (SP) survey was designed and collected 318 answers from motorcycle drivers. Various discrete choice models under the assumption of random utility maximizations (RUM), which included the mixed logit model, multinomial logit model, and nested logit model, were employed to evaluate the influence factors on motorcycle drivers’ parking choice behavior models. The results showed that the mixed logit model fit with the data. Parking fee, walking distance, the capacity of the parking lot, and queuing time have significant effects on parking lot choice modeling. However, navigation and street sign variables showed a lesser effect on the choices of motorcycle users. This study towards parking planning solution for motorcycles and the author expects that it would be helpful to further study on the parking lot in developing countries.
Integrating Cellular Automata with Unsupervised Deep-Learning Algorithms: A Case Study of Urban-Sprawl Simulation in the Jingjintang Urban Agglomeration, China
Authors: Ou Cong , Yang Jianyu , Du Zhenrong , Zhang Xin , Zhu Dehai
Published: April 2019

An effective simulation of the urban sprawl in an urban agglomeration is conducive to making regional policies. Previous studies verified the effectiveness of the cellular-automata (CA) model in simulating urban sprawl, and emphasized that the definition of transition rules is the key to the construction of the CA model. However, existing simulation models based on CA are limited in defining complex transition rules. The aim of this study was to investigate the capability of two unsupervised deep-learning algorithms (deep-belief networks, DBN) and stacked denoising autoencoders (SDA) to define transition rules in order to obtain more accurate simulated results. Choosing the Beijing–Tianjin–Tangshan urban agglomeration as the study area, two proposed models (DBN–CA and SDA–CA) were implemented in this area for simulating its urban sprawl during 2000–2010. Additionally, two traditional machine-learning-based CA models were built for comparative experiments. The implementation results demonstrated that integrating CA with unsupervised deep-learning algorithms is more suitable and accurate than traditional machine-learning algorithms on both the cell level and pattern level. Meanwhile, compared with the DBN–CA, the SDA–CA model had better accuracy in both aspects. Therefore, the unsupervised deep-learning-based CA model, especially SDA–CA, is a novel approach for simulating urban sprawl and also potentially for other complex geographical phenomena.
Experimental Study on the Shear Performance of Reinforced Concrete Beams Strengthened with Bolted Side-Plating
Authors: Liu Xin , Chen Yu , Li Ling-Zhi , Su Mei-Ni , Lu Zhou-Dao , Yu Ke-Quan
Published: April 2019

To investigate the residual shear capacity of post-fire bolted side-plated (BSP) reinforced concrete (RC) beams with different depths of steel plate and types of anchor adhesive, i.e., magnesium oxychloride cement (MOC) and HIT-RE500, a control beam and five BSP beams were fabricated, of which two were exposed to fire in accordance with ISO834 temperature curve. Four-point bending shear tests were conducted to investigate the influence of elevated temperature on the failure mode, cracking load, shear capacity, stiffness, ductility and strain development, etc. The shear capacities of RC beams were found to be improved significantly by using the BSP technique. However, the stiffness of BSP beams was seriously degraded after exposed to fire, but the reduction in shear capacity was negligible, whereas the ductility and the strain of longitudinal reinforcement were obviously increased. Thus, the failure-mode was changed from shear failure to flexural failure. Regarding the adhesive mortar used for bolt anchorage, magnesium oxychloride cement (MOC) achieved higher shear capacity and better ductility but lower stiffness for BSP beams compared with HIT-RE500. Additionally, increasing the depth of bolted steel plates effectively improved the shear performance of BSP beams. In the tests, uneven relative slips were observed on the plate-RC interface due to the shear deformation of bolt shafts and the plates’ tensile principal stress perpendicular to the main diagonal crack, which proved the deformation lag of the bolted steel plates with respect to the RC beam. The outcomes of this study provide a better understanding on the shear performance of BSP beams at room temperatures and at fire conditions.
The Utility of Data Transformation for Alignment, De Novo Assembly and Classification of Short Read Virus Sequences
Authors: Tapinos Avraam , Constantinides Bede , Phan My V. T. , Kouchaki Samaneh , Cotten Matthew , Robertson David L.
Published: April 2019

Advances in DNA sequencing technology are facilitating genomic analyses of unprecedented scope and scale, widening the gap between our abilities to generate and fully exploit biological sequence data. Comparable analytical challenges are encountered in other data-intensive fields involving sequential data, such as signal processing, in which dimensionality reduction (i.e., compression) methods are routinely used to lessen the computational burden of analyses. In this work, we explored the application of dimensionality reduction methods to numerically represent high-throughput sequence data for three important biological applications of virus sequence data: reference-based mapping, short sequence classification and de novo assembly. Leveraging highly compressed sequence transformations to accelerate sequence comparison, our approach yielded comparable accuracy to existing approaches, further demonstrating its suitability for sequences originating from diverse virus populations. We assessed the application of our methodology using both synthetic and real viral pathogen sequences. Our results show that the use of highly compressed sequence approximations can provide accurate results, with analytical performance retained and even enhanced through appropriate dimensionality reduction of sequence data.
Spent mushroom compost (SMC) – retrieved added value product closing loop in agricultural production
Authors: Jasińska Agnieszka
Published: April 2019

Worldwide edible mushroom production on agro-industrial residues comprises of more than 11 million tons of fresh mushrooms per year. For 1 kg of mushrooms there is 5 kg of spent mushroom compost (SMC). This enormous amount of waste results in disposal problems. However, SMC is a waste product of the mushroom industry, which contains mycelium and high levels of remnant nutrients such as organic substances (N, P, K). The spent mushroom compost is usually intended for utilization, but there are increasing numbers of experiments focusing on its reuse in agricultural and horticultural production. Recently, the increase of the global environmental consciousness and stringent legislation have focused research towards the application of sustainable and circular processes. Innovative and environmentally friendly systems of utilisation of waste streams have increased interest of the scientific community. Circular economy implies that agricultural waste will be the source for retrieving high value-added compounds. The goal of the present work was to carry out a bibliographic review of the different scenarios, regarding the exploitation of this low cost feedstock with huge potential for valorisation.