bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcriptomic Analysis of Planarians under Simulated Microgravity or 8 g Demonstrates That Alteration of Gravity Induces Genomic and Cellular Alterations That Could Facilitate Tumoral Transformation
Authors: de Sousa Nídia , Rodriguez-Esteban Gustavo , Colagè Ivan , D’Ambrosio Paolo , van Loon Jack J. W. A. , Saló Emili , Adell Teresa , Auletta Gennaro
Published: February 2019

The possibility of humans to live outside of Earth on another planet has attracted the attention of numerous scientists around the world. One of the greatest difficulties is that humans cannot live in an extra-Earth environment without proper equipment. In addition, the consequences of chronic gravity alterations in human body are not known. Here, we used planarians as a model system to test how gravity fluctuations could affect complex organisms. Planarians are an ideal system, since they can regenerate any missing part and they are continuously renewing their tissues. We performed a transcriptomic analysis of animals submitted to simulated microgravity (Random Positioning Machine, RPM) (s-µg) and hypergravity (8 g), and we observed that the transcriptional levels of several genes are affected. Surprisingly, we found the major differences in the s-µg group. The results obtained in the transcriptomic analysis were validated, demonstrating that our transcriptomic data is reliable. We also found that, in a sensitive environment, as under Hippo signaling silencing, gravity fluctuations potentiate the increase in cell proliferation. Our data revealed that changes in gravity severely affect genetic transcription and that these alterations potentiate molecular disorders that could promote the development of multiple diseases such as cancer.
Biomimetic Surfaces Coated with Covalently Immobilized Collagen Type I: An X-Ray Photoelectron Spectroscopy, Atomic Force Microscopy, Micro-CT and Histomorphometrical Study in Rabbits
Authors: Scarano Antonio , Lorusso Felice , Orsini Tiziana , Morra Marco , Iviglia Giorgio , Valbonetti Luca
Published: February 2019

Background: The process of osseointegration of dental implants is characterized by healing phenomena at the level of the interface between the surface and the bone. Implant surface modification has been introduced in order to increase the level of osseointegration. The purpose of this study is to evaluate the influence of biofunctional coatings for dental implants and the bone healing response in a rabbit model. The implant surface coated with collagen type I was analyzed through X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM), micro-CT and histologically. Methods: The sandblasted and double acid etched surface coated with collagen type I, and uncoated sandblasted and double acid etched surface were evaluated by X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM) analysis in order evaluate the different morphology. In vivo, a total of 36 implants were positioned in rabbit articular femoral knee-joint, 18 fixtures for each surface. Micro-CT scans, histological and histomorphometrical analysis were conducted at 15, 30 and 60 days. Results: A histological statistical differences were evident at 15, 30 and 60 days (p < 0.001). Both implant surfaces showed a close interaction with newly formed bone. Mature bone appeared in close contact with the surface of the fixture. The AFM outcome showed a similar roughness for both surfaces. Conclusion: However, the final results showed that a coating of collagen type I on the implant surface represents a promising procedure able to improve osseointegration, especially in regions with a low bone quality.
Targeting Autophagy to Overcome Human Diseases
Authors: Condello Maria , Pellegrini Evelin , Caraglia Michele , Meschini Stefania
Published: February 2019

Autophagy is an evolutionarily conserved cellular process, through which damaged organelles and superfluous proteins are degraded, for maintaining the correct cellular balance during stress insult. It involves formation of double-membrane vesicles, named autophagosomes, that capture cytosolic cargo and deliver it to lysosomes, where the breakdown products are recycled back to cytoplasm. On the basis of degraded cell components, some selective types of autophagy can be identified (mitophagy, ribophagy, reticulophagy, lysophagy, pexophagy, lipophagy, and glycophagy). Dysregulation of autophagy can induce various disease manifestations, such as inflammation, aging, metabolic diseases, neurodegenerative disorders and cancer. The understanding of the molecular mechanism that regulates the different phases of the autophagic process and the role in the development of diseases are only in an early stage. There are still questions that must be answered concerning the functions of the autophagy-related proteins. In this review, we describe the principal cellular and molecular autophagic functions, selective types of autophagy and the main in vitro methods to detect the role of autophagy in the cellular physiology. We also summarize the importance of the autophagic behavior in some diseases to provide a novel insight for target therapies.
Scutellaria baicalensis Alleviates Insulin Resistance in Diet-Induced Obese Mice by Modulating Inflammation
Authors: Na Hyun-Young , Lee Byung-Cheol
Published: February 2019

Insulin resistance is strongly associated with the metabolic syndrome, and chronic inflammation is known to be a major mechanism of insulin resistance and is a therapeutic target. This study was designed to evaluate the effect of Scutellaria baicalensis (SB) in high-fat diet (HFD)-induced insulin-resistant mice and to investigate its mechanism based on inflammatory responses. Mice were fed a HFD to induce insulin resistance and then administered SB for nine weeks. Body weight, glucose, lipid, insulin, epididymal fat pad and liver weights, and histologic characteristics were evaluated to determine the effect on insulin resistance. In order to evaluate the effects on the inflammatory process, we analyzed the proportions of macrophages in liver and epididymal fat and measured inflammatory gene expression. Fasting and postprandial glucose, fasting insulin, HOMA-IR, triglycerides, and low density lipoprotein cholesterol levels were significantly decreased by SB administration. The epididymal fat and liver showed significant weight decreases and histological improvements. Total adipose tissue macrophages (ATMs) decreased (27.71 ± 3.47% vs. 45.26 ± 7.26%, p < 0.05), M2 ATMs increased (47.02 ± 6.63% vs. 24.28 ± 8.00%, p < 0.05), and CD11b+ Kupffer cells decreased. The expression levels of tumor necrosis factor alpha and F4/80 in the liver were significantly decreased (12.03 ± 1.47% vs. 25.88 ± 4.57%, p < 0.05) compared to HFD group. These results suggest that SB improved insulin resistance through inhibition of macrophage-mediated inflammation.
Skeleton-Based Human Action Recognition through Third-Order Tensor Representation and Spatio-Temporal Analysis
Authors: Barmpoutis Panagiotis , Stathaki Tania , Camarinopoulos Stephanos
Published: February 2019

Given the broad range of applications from video surveillance to human–computer interaction, human action learning and recognition analysis based on 3D skeleton data are currently a popular area of research. In this paper, we propose a method for action recognition using depth sensors and representing the skeleton time series sequences as higher-order sparse structure tensors to exploit the dependencies among skeleton joints and to overcome the limitations of methods that use joint coordinates as input signals. To this end, we estimate their decompositions based on randomized subspace iteration that enables the computation of singular values and vectors of large sparse matrices with high accuracy. Specifically, we attempt to extract different feature representations containing spatio-temporal complementary information and extracting the mode-n singular values with regards to the correlations of skeleton joints. Then, the extracted features are combined using discriminant correlation analysis, and a neural network is used to recognize the action patterns. The experimental results presented use three widely used action datasets and confirm the great potential of the proposed action learning and recognition method.
Orthopedic Implant-Associated Infection by Multidrug Resistant Enterobacteriaceae
Authors: Pfang Bernadette G. , García-Cañete Joaquín , García-Lasheras Julia , Blanco Antonio , Auñón Álvaro , Parron-Cambero Raul , Macías-Valcayo Alicia , Esteban Jaime
Published: February 2019

Introduction: Orthopedic implant-associated infections caused by multidrug-resistant Enterobacteriaceae are a growing challenge for healthcare providers due to their increasing incidence and the difficulties of medical and surgical treatment. Material and Methods: A retrospective observational study of all cases of multidrug resistant Enterobacteriaceae orthopedic implant-associated infection diagnosed in a tertiary European hospital from December 2011 to November 2017 was carried out. Clinical records were reviewed using a previously designed protocol. Data analysis was performed with IBM® SPSS®, version 22. Results: 25 patients met inclusion criteria. The infected implants included 10 prosthetic joints, seven osteosyntheses, six combinations of prosthetic joint and osteosynthesis material, and two spacers. Of the multidrug resistant Enterobacteriaceae obtained on culture, 12 were extended-spectrum beta-lactamase-producing Escherichia coli, three OXA-48-producing Klebsiella pneumoniae, nine extended-spectrum beta-lactamase-producing Klebsiella pneumoniae, and one extended-spectrum beta-lactamase-producing Proteus mirabilis. Combination antimicrobial therapy was employed in all cases but two. Overall, 16 (64%) patients underwent implant removal. The rate of infection control in the overall implant removal group was 100% compared to 33% in the implant retention group. A strong relationship between implant removal and infection control was observed (p = 0.001). Discussion: Implant removal is strongly associated with infection control. However, in some cases, patient age and comorbidity contraindicate hardware extraction. Potential objectives for future studies should be geared towards targeting the population in which debridement, antibiotic therapy, and implant retention can be used as a first-line therapeutic strategy with a reasonable probability of achieving infection control.
An Evaluation of the Wind and Wave Dynamics along the European Coasts
Authors: Ganea Daniel , Mereuta Elena , Rusu Eugen
Published: February 2019

The objective of this work is to analyze the wind and wave conditions along the coasts of the European seas. The emphasis is put on the mean and maximum values. The areas studied are characterized by intense maritime activities, including traffic, as well as various harbor and offshore operations. In the present study, 35 years of data (1983–2017) coming from the European Centre for Medium-Range Weather Forecasts (ECMWF) were processed, corresponding to 40 different geographical locations. Thus, these 40 reference points are defined for some of the most relevant offshore locations in the coastal environments targeted. As regards the data considered in the analysis, two different sets were used. The first corresponds to the wave model, while the second to the atmospheric model, both operated by ECMWF. Finally, it can be concluded that the proposed work provides a global perspective related to the average and maximum wind and wave conditions and to a further extent on the climate dynamics along the coasts of the European seas.
Net Global Warming Potential of Spring Wheat Cropping Systems in a Semiarid Region
Authors: Liebig Mark , Archer David , Halvorson Jonathan , Johnson Holly , Saliendra Nicanor , Gross Jason , Tanaka Donald
Published: February 2019

Investigations of global warming potential (GWP) of semiarid cropping systems are needed to ascertain agriculture’s contributions to climate regulation services. This study sought to determine net GWP for three semiarid cropping systems under no-tillage management in the northern Great Plains of North America: spring wheat (Triticum aestivum L.)—fallow (SW-F), continuous spring wheat (CSW) and spring wheat—safflower (Carthamus tinctorius L.)—rye (Secale cereale L.) (SW-S-R). Management records, coupled with published carbon dioxide (CO2) emission estimates, were used to determine emissions from production inputs and field operations. Static chamber methodology was used to measure soil-atmosphere methane (CH4) and nitrous oxide (N2O) fluxes over a 3-year period and changes in profile soil organic carbon (SOC) stocks were determined over 18 years. Carbon dioxide emissions associated with production inputs and field operations were greatest for CSW, intermediate for SW-S-R and lowest for SW-F. All cropping systems were minor CH4 sinks (≤0.5 kg CH4-C ha−1 yr−1) and moderate N2O sources (1.0 to 2.8 kg N2O-N ha−1 yr−1). No differences in SOC stocks were observed among cropping systems (P = 0.78), nor did SOC stocks change significantly from baseline conditions (P = 0.82). Summing across factors, net GWP was positive for SW-F and CSW, implying net greenhouse gas (GHG) emission to the atmosphere, while net GWP for SW-S-R was negative, implying net GHG uptake. Net GWP, however, did not differ among cropping systems (P = 0.17). Management practices that concurrently improve N use efficiency and increase SOC stocks are needed for semiarid cropping systems to be net GHG sinks.
Study of the Dynamic Recrystallization Process of the Inconel625 Alloy at a High Strain Rate
Authors: Jia Zhi , Gao Zexi , Ji Jinjin , Liu Dexue , Guo Tingbiao , Ding Yutian
Published: February 2019

High-temperature compression and electron backscatter diffraction (EBSD) techniques were used in a systematic investigation of the dynamic recrystallization (DRX) behavior and texture evolution of the Inconel625 alloy. The true stress–true strain curves and the constitutive equation of Inconel625 were obtained at temperatures ranging from 900 to 1200 °C and strain rates of 10, 1, 0.1, and 0.01 s−1. The adiabatic heating effect was observed during the hot compression process. At a high strain rate, as the temperature increased, the grains initially refined and then grew, and the proportion of high-angle grain boundaries increased. The volume fraction of the dynamic recrystallization increased. Most of the grains were randomly distributed and the proportion of recrystallized texture components first increased and then decreased. Complete dynamic recrystallization occurred at 1100 °C, where the recrystallized volume fraction and the random distribution ratios of grains reached a maximum. This study indicated that the dynamic recrystallization mechanism of the Inconel625 alloy at a high strain rate included continuous dynamic recrystallization with subgrain merging and rotation, and discontinuous dynamic recrystallization with bulging grain boundary induced by twinning. The latter mechanism was less dominant.
The Yawing Behavior of Horizontal-Axis Wind Turbines: A Numerical and Experimental Analysis
Authors: Castellani Francesco , Astolfi Davide , Natili Francesco , Mari Francesco
Published: February 2019

The yawing of horizontal-axis wind turbines (HAWT) is a major topic in the comprehension of the dynamical behavior of these kinds of devices. It is important for the study of mechanical loads to which wind turbines are subjected and it is important for the optimization of wind farms because the yaw active control can steer the wakes between nearby wind turbines. On these grounds, this work is devoted to the numerical and experimental analysis of the yawing behavior of a HAWT. The experimental tests have been performed at the wind tunnel of the University of Perugia on a three-bladed small HAWT prototype, having two meters of rotor diameter. Two numerical set ups have been selected: a proprietary code based on the Blade Element Momentum theory (BEM) and the aeroelastic simulation software FAST, developed at the National Renewable Energy Laboratory (NREL) in Golden, CO, USA. The behavior of the test wind turbine up to ± 45 ∘ of yaw offset is studied. The performances (power coefficient C P ) and the mechanical behavior (thrust coefficient C T ) are studied and the predictions of the numerical models are compared against the wind tunnel measurements. The results for C T inspire a subsequent study: its behavior as a function of the azimuth angle is studied and the periodic component equal to the blade passing frequency 3P is observed. The fluctuation intensity decreases with the yaw angle because the distance between tower and blade increases. Consequently, the tower interference is studied through the comparison of measurements and simulations as regards the fore-aft vibration spectrum and the force on top of the tower.
Targeted Therapies in Cholangiocarcinoma: Emerging Evidence from Clinical Trials
Authors: Simile Maria Maddalena , Bagella Paola , Vidili Gianpaolo , Spanu Angela , Manetti Roberto , Seddaiu Maria Antonietta , Babudieri Sergio , Madeddu Giordano , Serra Pier Andrea , Altana Matteo , Paliogiannis Panagiotis
Published: February 2019

Cholangiocarcinoma (CCA) is a highly-aggressive malignancy arising from the biliary tree, characterized by a steady increase in incidence globally and a high mortality rate. Most CCAs are diagnosed in the advanced and metastatic phases of the disease, due to the paucity of signs and symptoms in the early stages. This fact, along with the poor results of the local and systemic therapies currently employed, is responsible for the poor outcome of CCA patients and strongly supports the need for novel therapeutic agents and strategies. In recent years, the introduction of next-generation sequencing technologies has opened new horizons for a better understanding of the genetic pathophysiology of CCA and, consequently, for the identification and evaluation of new treatments tailored to the molecular features or alterations progressively elucidated. In this review article, we describe the potential targets under investigation and the current molecular therapies employed in biliary tract cancers. In addition, we summarize the main drugs against CCA under evaluation in ongoing trials and describe the preliminary data coming from these pioneering studies.
Digital Subtraction Pulmonary Angiography in Children with Pulmonary Hypertension due to Bronchopulmonary Dysplasia
Authors: Das Bibhuti , Jadotte Michelle-Marie , Mills Jaime , Chan Kak-Chen
Published: February 2019

Bronchopulmonary dysplasia (BPD) is the most common respiratory sequelae of prematurity and histopathologically features fewer, dysmorphic, pulmonary arteries. We present our experience with the digital subtraction pulmonary angiography (DSPA) findings of a segmental vascular filling abnormality in three children who were born at extreme prematurity and have pulmonary hypertension due to severe BPD. Our preliminary data suggest that DSPA may be useful in evaluating the severity of pulmonary vascular disease in children with BPD.
Development of Low Silver AgCuZnSn Filler Metal for Cu/Steel Dissimilar Metal Joining
Authors: Xue Peng , Zou Yang , He Peng , Pei Yinyin , Sun Huawei , Ma Chaoli , Luo Jingyi
Published: February 2019

The microstructure and properties of a Cu/304 stainless steel dissimilar metal joint brazed with a low silver Ag16.5CuZnSn-xGa-yCe braze filler after aging treatment were investigated. The results indicated that the addition of Ce could reduce the intergranular penetration depth of the filler metal into the stainless steel during the aging process. The minimum penetration depth in the Ag16.5CuZnSn-0.15Ce brazed joint was decreased by 48.8% compared with the Ag16.5CuZnSn brazed joint. Moreover, the shear strength of the brazed joint decreased with aging time while the shear strength of the AgCuZnSn-xGa-yCe joint was still obviously higher than the Ag16.5CuZnSn joint after a 600 h aging treatment. The fracture type of the Ag16.5CuZnSn-xGa-yCe brazed joints before aging begins ductile and turns slightly brittle during the aging process. Compared to all the results, the Ag16.5CuZnSn-2Ga-0.15Ce brazed joints show the best performance and could satisfy the requirements for cost reduction and long-term use.
Application of Ion Exchange for Preparation of Selected Metal Perrhenates—Precursors for Superalloy Production
Authors: Leszczyńska-Sejda Katarzyna , Benke Grzegorz , Kopyto Dorota , Drzazga Michał , Ciszewski Mateusz
Published: February 2019

Methods for the preparation of selected metal perrhenates and their mixtures are presented in this paper. These materials are suitable for reduction, and therefore for production of alloy powders containing rhenium and other superalloy components, i.e., Cr, Ni and Co. Prepared compounds may be also used as substrates for electrowinning of binary and ternary rhenium alloys. All developed methods are based on an ion exchange technique. This technique allows management of waste solutions, limitation of valuable metals losses, and, importantly, production of high-purity components.
Carbon Sources and the Graphitization of Carbonaceous Matter in Precambrian Rocks of the Keivy Terrane (Kola Peninsula, Russia)
Authors: Fomina Ekaterina , Kozlov Evgeniy , Lokhov Kirill , Lokhova Olga , Bocharov Vladimir
Published: February 2019

The Precambrian rocks of the Keivy Terrane reveal five types of carbonaceous matter (CM): Fine-grained, flaky, nest, vein, and spherulitic. These types differ in their distribution character, carbon isotope composition, and graphitization temperatures calculated by the Raman spectra of carbonaceous material (RSCM) geothermometry. Supracrustal rocks of the Keivy Terrane contain extremely isotopically light (δ13CPDB = –43 ± 3‰) carbon. Presumably, its source was a methane–aqueous fluid. According to temperature calculations, this carbon matter and the host strata underwent at least two stages of metamorphism in the west of the Keivy Terrane and one stage in the east. The CM isotope signatures of several samples of kyanite schists (δ13CPDB = –33 ± 5‰) are close to those of oils and oil source rocks, and they indicate an additional carbon reservoir. Thus, in the Keivy territory, an oil-and-gas bearing basin has existed. Heavy carbon (δ13CPDB = −8 ± 3‰) precipitated from an aqueous CO2-rich fluid is derived from either the lower crust or the mantle. This fluid probably migrated from the Keivy alkaline granites into the surrounding rocks previously enriched with “methanogenic” carbon.
Evaluation of MMP Inhibitors Isolated from Ligustrum japonicum Fructus
Authors: Kim Hojun , Karadeniz Fatih , Kong Chang-Suk , Seo Youngwan
Published: February 2019

The current study investigated the ability of two secoiridoids, GL-3 (1) and oleonuezhenide (2), isolated from the fruits of Ligustrum japonicum to inhibit MMP-2 and -9 activity in phorbol 12-myristate 13-acetate (PMA)-induced HT-1080 human fibrosarcoma cells. Both compounds 1 and 2 were able to exert lowered gelatin digestion activity for MMP-2 and -9 tested by gelatin zymography via suppressing the release of MMPs to culture medium according to ELISA results. Treatment with compounds was also able to suppress the expression of both mRNA and protein levels of MMP-2 and -9. Action mechanism behind the MMP inhibitory effect of the compounds was suggested to be via MAPK pathway indicated by decreased levels of phosphorylated p38, ERK and JNK proteins evaluated employing immunoblotting. Compound 1 was shown to be slightly more active to inhibit MMP-2 and -9, however, compound 2 showed more regular dose-dependency during inhibition. In conclusion, this study suggested that GL-3 and oleonuezhenide were notable natural origin potent MMP inhibitors and could serve as lead compounds for development of anti-invasive MMP inhibitors against tumor metastasis.
Animal Source Food Consumption in Young Children from Four Regions of Ethiopia: Association with Religion, Livelihood, and Participation in the Productive Safety Net Program
Authors: Potts Kaitlin S. , Mulugeta Afework , Bazzano Alessandra N.
Published: February 2019

Introduction: Child undernutrition remains a challenge globally and in the geographically diverse country of Ethiopia. Improving dietary diversity and consumption of animal source foods are important for improving child nutrition and corresponding health outcomes. Objective: The objective of the study was to identify household and community factors associated with consumption of animal source foods among 6 to 36-month-old children from four regions of Ethiopia. Methods: A cross-sectional survey using multistage probability sampling in eight geographic zones and four regions of Ethiopia took place in 2015 with parents/caretakers of 6 to 36-month-old children. Data was collected on demographic information, proxy indicators of socioeconomic status, and food consumed by the child the day before the survey. Results: Increased child age, pastoral livelihood, Muslim religion, and participation in the Productive Safety Net Program were associated with increased consumption of animal source foods. Odds of animal source foods consumption increased by 8% with each 3-month age increase. Children from pastoralist households were the most likely to have consumed animal source foods in the preceding 24 hours as compared with those in agro-pastoralist households (0.21 times as likely) or those in agriculturalist/farming households (0.15 times as likely). The odds of consumption of animal source foods for families with food aid or safety net support was 1.7 times greater among those receiving traditional support from the Productive Safety Net Program and 4.5 times greater for those in the direct support arm of the program. Conclusions: The findings illustrate the importance of accounting for local context and community characteristics, such as livelihood and religion, when undertaking programming designed to improve diversity of children’s diets through increasing animal source foods. In addition, the Productive Safety Net Program may be a critical determinant of dietary diversity for young children in these regions.
Phosphorus Containing Polyacrylamides as Flame Retardants for Epoxy-Based Composites in Aviation
Authors: Greiner Lara , Kukla Philipp , Eibl Sebastian , Döring Manfred
Published: February 2019

Novel polymeric flame retardants based on two acrylamides and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) or 5,5-dimethyl-[1,3,2]dioxaphosphinane-2-oxide (DDPO) are described for several applications in HexFlow® RTM6, a high-performance epoxy resin. Neat resin samples and carbon fiber-reinforced composites were tested for their glass transition temperatures (dynamic mechanical analysis), thermal stability (thermogravimetric analyses), flammability (UL94) and flame-retardant performance (Cone Calorimetry). Additionally, the fiber degradation occurring during combustion of carbon fiber-reinforced epoxy resins was observed by scanning electron microscopy to show the fiber protecting effect of these flame retardants. Whereas DOPO-containing polyacrylamides acting mainly in the gas phase showed the best flame retardant efficiency, DDPO-containing polyacrylamides acting mainly in the condensed phase showed the best fiber protection. A mixed polyacrylamide was synthesized to combine these effects. This thermoplastic is soluble in the resin and, therefore, suitable for injection molding processes. Interlaminar shear strength measurements showed no negative effect of the flame retardant. The versatility of these flame retardants is shown by investigations dealing with boehmite as synergist in neat resin samples.
Modeling, Management, and Control of an Autonomous Wind/Fuel Cell Micro-Grid System
Authors: Atawi Ibrahem E. , Kassem Ahmed M. , Zaid Sherif A.
Published: February 2019

This paper proposes a microelectric power grid that includes wind and fuel cell power generation units, as well as a water electrolyzer for producing hydrogen gas. The grid is loaded by an induction motor (IM) as a dynamic load and constant impedance load. An optimal control algorithm using the Mine Blast Algorithm (MBA) is designed to improve the performance of the proposed renewable energy system. Normally, wind power is adapted to feed the loads at normal circumstances. Nevertheless, the fuel cell compensates extra load power demand. An optimal controller is applied to regulate the load voltage and frequency of the main power inverter. Also, optimal vector control is applied to the IM speed control. The response of the microgrid with the proposed optimal control is obtained under step variation in wind speed, load impedance, IM rotor speed, and motor mechanical load torque. The simulation results indicate that the proposed renewable generation system supplies the system loads perfectly and keeps up the desired load demand. Furthermore, the IM speed performance is acceptable under turbulent wind speed.
An Effective Similar-Pixel Reconstruction of the High-Frequency Cloud-Covered Areas of Southwest China
Authors: Yu Wenping , Tan Junlei , Ma Mingguo , Li Xiaolu , She Xiaojun , Song Zengjing
Published: February 2019

With advantages of multispatial resolutions, a high retrieval accuracy, and a high temporal resolution, the satellite-derived land surface temperature (LST) products are very important LST sources. However, the greatest barrier to their wide application is the invalid values produced by large quantities of cloudy pixels, especially for regions frequently swathed in clouds. In this study, an effective method based on the land energy balance theory and similar pixels (SP) method was developed to reconstruct the LSTs over cloudy pixels for the widely used MODIS LST (MOD11A1). The southwest region of China was selected as the study area, where extreme drought has frequently occurred in recent years in the context of global climate change and which commonly exhibits cloudy and foggy weather. The validation results compared with in situ LSTs showed that the reconstructed LSTs have an average error < 1.00 K (0.57 K at night and −0.14 K during the day) and an RMSE < 3.20 K (1.90 K at night and 3.16 K in the daytime). The experiment testing the SP interpolation indicated that the spatial structure of the LST has a greater effect on the SP performance than the size of the data-missing area, which benefits the LST reconstruction in the area frequently covered by large clouds.
Object Detection in Remote Sensing Images Based on a Scene-Contextual Feature Pyramid Network
Authors: Chen Chaoyue , Gong Weiguo , Chen Yongliang , Li Weihong
Published: February 2019

Object detection has attracted increasing attention in the field of remote sensing image analysis. Complex backgrounds, vertical views, and variations in target kind and size in remote sensing images make object detection a challenging task. In this work, considering that the types of objects are often closely related to the scene in which they are located, we propose a convolutional neural network (CNN) by combining scene-contextual information for object detection. Specifically, we put forward the scene-contextual feature pyramid network (SCFPN), which aims to strengthen the relationship between the target and the scene and solve problems resulting from variations in target size. Additionally, to improve the capability of feature extraction, the network is constructed by repeating a building aggregated residual block. This block increases the receptive field, which can extract richer information for targets and achieve excellent performance with respect to small object detection. Moreover, to improve the proposed model performance, we use group normalization, which divides the channels into groups and computes the mean and variance for normalization within each group, to solve the limitation of the batch normalization. The proposed method is validated on a public and challenging dataset. The experimental results demonstrate that our proposed method outperforms other state-of-the-art object detection models.
Development and Validation of Ambulosono: A Wearable Sensor for Bio-Feedback Rehabilitation Training
Authors: Chomiak Taylor , Sidhu Abhijot , Watts Alexander , Su Luke , Graham Brian , Wu Joshua , Classen Suzanne , Falter Brian , Hu Bin
Published: February 2019

Wearable technology-based measurement systems hold potential for the therapeutic and rehabilitation management of patients with various chronic diseases. The purpose of this study was to assess the accuracy and test–retest reliability of a new-generation wearable sensor-based system, dubbed Ambulosono, for bio-feedback training. The Ambulosono sensor system was cross-validated by comparing its functionality with the iPod touch (4th generation) sensor system. Fifteen participants underwent a gait test to measure various gait parameters while wearing both the iPod-based and Ambulosono sensors simultaneously. The physically measured values (i.e., the true values) of step length, distance traveled, velocity, and cadence were then compared to those obtained via the two-sensor systems using the same calculation algorithms. While the mean percentage error was <10% for all measured parameters, and the intra-class correlation coefficient revealed a high level of agreement between trials for both sensor systems, it was found that the Ambulosono sensor system outperformed the iPod-based system in some respects. The Ambulosono sensor system possessed both reliability and accuracy in obtaining gait parameter measurements, which suggests it can serve as an economical alternative to the iPod-based system that is currently used in various clinical rehabilitation programs.
Real-Time Monocular Visual Odometry for Turbid and Dynamic Underwater Environments
Authors: Ferrera Maxime , Moras Julien , Trouvé-Peloux Pauline , Creuze Vincent
Published: February 2019

In the context of underwater robotics, the visual degradation induced by the medium properties make difficult the exclusive use of cameras for localization purpose. Hence, many underwater localization methods are based on expensive navigation sensors associated with acoustic positioning. On the other hand, pure visual localization methods have shown great potential in underwater localization but the challenging conditions, such as the presence of turbidity and dynamism, remain complex to tackle. In this paper, we propose a new visual odometry method designed to be robust to these visual perturbations. The proposed algorithm has been assessed on both simulated and real underwater datasets and outperforms state-of-the-art terrestrial visual SLAM methods under many of the most challenging conditions. The main application of this work is the localization of Remotely Operated Vehicles used for underwater archaeological missions, but the developed system can be used in any other applications as long as visual information is available.
Novel Adhesion Technique Using Metallic or Non-Metallic Hydrous Oxide of Metal Complexes Involving Magnetic Compound Fluid Rubber under Electrolytic Polymerization and Magnetic Field for Producing Sensors
Authors: Shimada Kunio , Kikura Hiroshige , Takahashi Hideharu , Ikeda Ryo
Published: February 2019

As per sequential studies on new types of soft rubber for the artificial skin of robots, smart sensors, etc., we have proposed and investigated hybrid skin (H-Skin) and haptic sensors by using magnetic compound fluid (MCF), compounding natural rubber latex (NR-latex), and applying electric and magnetic fields. Through electrolytic polymerization, the MCF rubber is solidified. The MCF rubber has hybrid sensing functions and photovoltaic effects, and electric charge as battery. In case of the production of soft rubber sensors, however, the problem of adhesion between metal electrodes and rubber is very important. In the present study, we propose a novel adhesive technique for bonding the metal electrodes and MCF rubber by using metallic or non-metallic hydrous oxide, which is a metal complex, via electrolytic polymerization. The anionic radical hydrate reacts with the isoprene molecules of NR-latex or chloroprene rubber latex (CR-latex) such that they are cross-linked and the MCF rubber with the hydrate is solidified, which can be represented via a chemical reaction equation. By means of this adhesive technique, we presented five cases of sensors fabricated using metal electrodes and rubbers. This technique is applicable for novel cohesion between rubber and metal.
Ultrasensitive Immunosensor Array for TNF-α Detection in Artificial Saliva using Polymer-Coated Magnetic Microparticles onto Screen-Printed Gold Electrode
Authors: Barhoumi Lassaad , Bellagambi Francesca G. , Vivaldi Federico M. , Baraket Abdoullatif , Clément Yohann , Zine Nadia , Ben Ali Mounir , Elaissari Abdelhamid , Errachid Abdelhamid
Published: February 2019

Tumor necrosis factor-α (TNF-α) is a biomarker of inflammation that occurs in patients suffering from heart failure (HF). Saliva can be sampled in a non-invasive way, and it is currently gaining importance as matrix alternative to blood in diagnostic and therapy monitoring. This work presents the development of an immunosensor array based on eight screen-printed gold electrodes to detect TNF-α in saliva samples. Two different functionalization strategies of electrodes were compared. In the first, anti-TNF-α antibodies were chemically bonded onto the electrode by functionalization with 4-carboxymethylaniline. The other functionalization procedure involved the binding of antibodies onto polymer-coated magnetic microparticles, which were then deposited onto the electrode by pulsed chronoamperometry. Finally, the chronoamperometry technique was applied to characterize the modified SPEAu. The use of a secondary antibody anti-TNF-α (Ab-TNF-α-HRP) labelled with horseradish peroxidase (HRP, 2 µg·mL−1) was investigated using tetramethylbenzidine (TMB, pH = 3.75) as electrochemical substrate containing 0.2 mM of H2O2. A sandwich-type detection strategy with a secondary antibody anti-TNF-α provided chronoamperometric analyses in 10 s for each sample. Linearity, precision, limit of detection, and selectivity of devices were investigated. Interferences were evaluated by analyzing solutions containing other cytokine produced during the acute stage of inflammation. The immunosensor showed good performance within the clinically relevant concentration range, with a precision of 8%, and a limit of detection of 0.3 pg/mL. Therefore, it may represent a promising tool for monitoring HF in a non-invasive way.
An Approach to Automatic Hard Exudate Detection in Retina Color Images by a Telemedicine System Based on the d-Eye Sensor and Image Processing Algorithms
Authors: Saeed Emil , Szymkowski Maciej , Saeed Khalid , Mariak Zofia
Published: February 2019

Hard exudates are one of the most characteristic and dangerous signs of diabetic retinopathy. They can be marked during the routine ophthalmological examination and seen in color fundus photographs (i.e., using a fundus camera). The purpose of this paper is to introduce an algorithm that can extract pathological changes (i.e., hard exudates) in diabetic retinopathy. This was a retrospective, nonrandomized study. A total of 100 photos were included in the analysis—50 sick and 50 normal eyes. Small lesions in diabetic retinopathy could be automatically diagnosed by the system with an accuracy of 98%. During the experiments, the authors used classical image processing methods such as binarization or median filtration, and data was read from the d-Eye sensor. Sixty-seven patients (39 females and 28 males with ages ranging between 50 and 64) were examined. The results have shown that the proposed solution accuracy level equals 98%. Moreover, the algorithm returns correct classification decisions for high quality images and low quality samples. Furthermore, we consider taking retina photos using mobile phones rather than fundus cameras, which is more practical. The paper presents an innovative approach. The results are introduced and the algorithm is described.
BL0K: A New Stage of Privacy-Preserving Scope for Location-Based Services
Authors: Albelaihy Abdullah , Thayananthan Vijey
Published: February 2019

Location-based services present an inherent challenge of finding the delicate balance between efficiency when answering queries and maintaining user privacy. Inevitable security issues arise as the server needs to be informed of the query location to provide accurate responses. Despite the many advancements in localization security in wireless sensor networks, servers can still be infected with malicious software. It is now possible to ensure queries do not generate any fake responses that may appear real to users. When a fake response is used, there are mechanisms that can be employed so that the user can identify the authenticity of the query. For this reason, this paper proposes Bloom Filter 0 Knowledge (BL0K), which is novel phase privacy method that preserves the framework for location-based service (LBS) and combines a Bloom filter and the Zero knowledge protocol. The usefulness of these methods has been shown for securing private user information. Analysis of the results demonstrated that BL0K performance is decidedly better when compared to the referenced approaches using the privacy entropy metric.
Content-Sensing Based Resource Allocation for Delay-Sensitive VR Video Uploading in 5G H-CRAN
Authors: Yang Junchao , Luo Jiangtao , Lin Feng , Wang Junxia
Published: February 2019

Virtual reality (VR) is emerging as one of key applications in future fifth-generation (5G) networks. Uploading VR video in 5G network is expected to boom in near future, as general consumers could generate high-quality VR videos with portable 360-degree cameras and are willing to share with others. Heterogeneous networks integrating with 5G cloud-radio access networks (H-CRAN) provides high transmission rate for VR video uploading. To address the motion characteristic of UE (User Equipments) and small cell feature of 5G H-CRAN, in this paper we proposed a content-sensing based resource allocation scheme for delay-sensitive VR video uploading in 5G H-CRAN, in which the source coding rate of uploading VR video is determined by the centralized RA scheduling. This scheme jointly optimizes g-NB group resource allocation, RHH/g-NB association, sub-channel assignment, power allocation, and tile encoding rate assignment as formulated in a mixed-integer nonlinear problem (MINLP). To solve the problem, a three stage algorithm is proposed. Dynamic g-NB group resource allocation is first performed according to the UE density of each group. Then, joint RRH/g-NB association, sub-channel allocation and power allocation is performed by an iterative process. Finally, encoding tile rate is assigned to optimize the target objective by adopting convex optimization toolbox. The simulation results show that our proposed algorithm ensures the total utility of system under the constraint of maximum transmission delay and power, which also with low complexity and faster convergence.
A New Method for Refining the GNSS-Derived Precipitable Water Vapor Map
Authors: Liu Chen , Zheng Nanshan , Zhang Kefei , Liu Junyu
Published: February 2019

The objective of the study was to put forth an interpolation method (the LZ method) for refining the GNSS-derived precipitable water vapor (PWV) map. We established a regional weighted mean temperature (Tm) model for this experiment, which introduced a minor difference into the resultant GNSS-derived PWV compared to the previous Tm models. The kernel of the LZ method consists of increasing the sample density via the virtual sample points. These virtual sample points originated from the digital elevation model (DEM) were constructed on the basis of the statistically significant correlation between PWV and geographical location (i.e., geographical coordinates and elevation). The LZ method was validated and compared to the conventional interpolation approach only accounting for the original sample points. The results reflect that the PWV maps generated by the LZ method showed more details than through conventional one. In addition, the prediction performance of the LZ method was better than that of the conventional method by using cross-validation.
A New Multivariate Optical Computing Microelement and Miniature Sensor for Spectroscopic Chemical Sensing in Harsh Environments: Design, Fabrication, and Testing
Authors: Jones Christopher M. , Dai Bin , Price Jimmy , Li Jian , Pearl Megan , Soltmann Bill , Myrick Michael L.
Published: February 2019

Multivariate optical computing (MOC) is a compressed sensing technique with the ability to provide accurate spectroscopic compositional analysis in a variety of different applications to multiple industries. Indeed, recent developments have demonstrated the successful deployment of MOC sensors in downhole/well-logging environments to interrogate the composition of hydrocarbon and other chemical constituents in oil and gas reservoirs. However, new challenges have necessitated sensors that operate at high temperatures and pressures (up to 230 °C and 138 MPa) as well as even smaller areas that require the miniaturization of their physical footprint. To this end, this paper details the design, fabrication, and testing of a novel miniature-sized MOC sensor suited for harsh environments. A micrometer-sized optical element provides the active spectroscopic analysis. The resulting MOC sensor is no larger than two standard AAA batteries yet is capable of operating in high temperature and pressure conditions while providing accurate spectroscopic compositional analysis comparable to a laboratory Fourier transform infrared spectrometer.
A Survey on Unmanned Surface Vehicles for Disaster Robotics: Main Challenges and Directions
Authors: Jorge Vitor A. M. , Granada Roger , Maidana Renan G. , Jurak Darlan A. , Heck Guilherme , Negreiros Alvaro P. F. , dos Santos Davi H. , Gonçalves Luiz M. G. , Amory Alexandre M.
Published: February 2019

Disaster robotics has become a research area in its own right, with several reported cases of successful robot deployment in actual disaster scenarios. Most of these disaster deployments use aerial, ground, or underwater robotic platforms. However, the research involving autonomous boats or Unmanned Surface Vehicles (USVs) for Disaster Management (DM) is currently spread across several publications, with varying degrees of depth, and focusing on more than one unmanned vehicle—usually under the umbrella of Unmanned Marine Vessels (UMV). Therefore, the current importance of USVs for the DM process in its different phases is not clear. This paper presents the first comprehensive survey about the applications and roles of USVs for DM, as far as we know. This work demonstrates that there are few current deployments in disaster scenarios, with most of the research in the area focusing on the technological aspects of USV hardware and software, such as Guidance Navigation and Control, and not focusing on their actual importance for DM. Finally, to guide future research, this paper also summarizes our own contributions, the lessons learned, guidelines, and research gaps.
Extended Codebook with Multispectral Sequences for Background Subtraction
Authors: Liu Rongrong , Ruichek Yassine , El Bagdouri Mohammed
Published: February 2019

The Codebook model is one of the popular real-time models for background subtraction. In this paper, we first extend it from traditional Red-Green-Blue (RGB) color model to multispectral sequences. A self-adaptive mechanism is then designed based on the statistical information extracted from the data themselves, with which the performance has been improved, in addition to saving time and effort to search for the appropriate parameters. Furthermore, the Spectral Information Divergence is introduced to evaluate the spectral distance between the current and reference vectors, together with the Brightness and Spectral Distortion. Experiments on five multispectral sequences with different challenges have shown that the multispectral self-adaptive Codebook model is more capable of detecting moving objects than the corresponding RGB sequences. The proposed research framework opens a door for future works for applying multispectral sequences in moving object detection.