bluuebunny/crossref_metadata_2025 huggingface dataset:
Inter-turn Short Circuit Diagnosis Using New D-Q Synchronous Min–Max Coordinate System and Linear Discriminant Analysis
Authors: Goh Yeong-Jin , Kim Kyoung-Min
Published: March 2020

In this paper, a direct-quadrature (D-Q) synchronous min–max coordinate system is proposed (as a new method) for diagnosing the occurrence of inter-turn short circuits (ITSC) of three-phase induction motors, and it was found that this method can linearly diagnose such short circuits using only the maximum value of the d-axis current component from the heavy load to the full load. In the diagnosis of ITSC, a method to perform linear discriminant analysis (LDA) efficiently was applied owing to the difficulty of linear separation under light load conditions. In the aforementioned method, time burden is generated because operations are performed for the entire data and between classes. However, the proposed method is useful even when it is applied to the entire load with only the LDA eigenvector of the minimum light load. This is proved by the graphical evaluation of the interaction between the false acceptance rate (FAR) and false recognition rate (FRR), and the results demonstrate that the proposed method is more efficient than existing LDA application methods.
An End-to-End Grasping Stability Prediction Network for Multiple Sensors
Authors: Shu Xin , Liu Chang , Li Tong
Published: March 2020

As we all know, the output of the tactile sensing array on the gripper can be used to predict grasping stability. Some methods utilize traditional tactile features to make the decision and some advanced methods use machine learning or deep learning ways to build a prediction model. While these methods are all limited to the specific sensing array and have two common disadvantages. On the one hand, these models cannot perform well on different sensors. On the other hand, they do not have the ability of inferencing on multiple sensors in an end-to-end manner. Thus, we aim to find the internal relationships among different sensors and inference the grasping stability of multiple sensors in an end-to-end way. In this paper, we propose the MM-CNN (mask multi-head convolutional neural network), which can be utilized to predict the grasping stability on the output of multiple sensors with the weight sharing mechanism. We train this model and evaluate it on our own collected datasets. This model achieves 99.49% and 94.25% prediction accuracy on two different sensing arrays, separately. In addition, we show that our proposed structure is also available for other CNN backbones and can be easily integrated.
Mechanical Behavior of Circular Steel Tubular Beam-Columns Corroded Uniformly in Atmospheric Environment
Authors: Wu Zhaoqi , Wei Yuan , Wang Xintao , Huang Chao , Jiang Shao-Fei
Published: March 2020

Circular steel tube members with the absence of anticorrosive protection or coating failure are prone to uniform corrosion, which threatens the reliability and safety of members in the atmospheric environment. To fully study the mechanical behavior of uniformly corroded circular steel tubes, compression test and theoretical analysis were conducted, and two methods considering section reduction and material degradation, respectively, were adopted for the calculation of ultimate load carrying capacities of specimens. The results indicate that uniform corrosion did not change the failure modes of specimens, and all of them belonged to global buckling failure. The load carrying capacities and stiffness of specimens decreased with the increase of corrosion ratio, and the degree of reduction was greater than that of material degradation, showing a linear relationship with the corrosion rate. Under the same corrosion ratio, the specimens with larger eccentricity represented more obvious load carrying capacity and stiffness degradation. The load carrying capacities predicted by both methods were in good agreement with the test results and had a certain safety margin. The conservative degree of calculation results from three specifications followed a descending order of ANSI/AISC 360-16, GB 50017-2017, and EN 1993-1-1. Under the same corrosion ratio, the load carrying capacity variation of specimens between one-sided corrosion and two-sided corrosion was less than 3%.
Classification of Brain Tumors from MRI Images Using a Convolutional Neural Network
Authors: Badža Milica M. , Barjaktarović Marko Č.
Published: March 2020

The classification of brain tumors is performed by biopsy, which is not usually conducted before definitive brain surgery. The improvement of technology and machine learning can help radiologists in tumor diagnostics without invasive measures. A machine-learning algorithm that has achieved substantial results in image segmentation and classification is the convolutional neural network (CNN). We present a new CNN architecture for brain tumor classification of three tumor types. The developed network is simpler than already-existing pre-trained networks, and it was tested on T1-weighted contrast-enhanced magnetic resonance images. The performance of the network was evaluated using four approaches: combinations of two 10-fold cross-validation methods and two databases. The generalization capability of the network was tested with one of the 10-fold methods, subject-wise cross-validation, and the improvement was tested by using an augmented image database. The best result for the 10-fold cross-validation method was obtained for the record-wise cross-validation for the augmented data set, and, in that case, the accuracy was 96.56%. With good generalization capability and good execution speed, the new developed CNN architecture could be used as an effective decision-support tool for radiologists in medical diagnostics.
A Soft, Biocompatible Magnetic Field Enabled Wireless Surgical Lighting Patty for Neurosurgery
Authors: Kim Woo Seok , Hong Sungcheol , Morgan Clinton , Nakaji Peter , Lawton Michael T. , Park Sung Il
Published: March 2020

General surgical procedures are subject to low-light conditions or a narrow angle of view, and such limitations in light limit visibility and complicate the given surgical procedure. Conventional lighted surgical tools rely on an external light source, which may be oriented into a cavity or mounted on a surgical instrument such as retractor, endoscopes, or suction tubes. However, such conventional lighted instruments do not provide adequate lighting during various surgical procedures. Here, we present a soft, miniaturized magnetic-enabled wireless surgical lighting patty. Specifically, the proposed surgical lighting patty that can be temporarily implanted into a cavity or surgical corridor provides lighting to the surgical subject and manages fluids in a surgical field. The surgical lighting patty is a multilayer patty, two outer layers of the lighted surgical patty and the center lighted layer. A reed switch in the central layer can activate the power supply in response to a magnet to emit the light from the light source. The result allows a dramatically simplified wireless operation. Moreover, it can provide various wavelengths of light to a surgical field for purposes such as illuminating the surgeon’s field of vision, exciting dyes, and sterilizing surgical fields.
Application and Research of Swirling Curtain Dust Collection Technology in Mines
Authors: Li Gang , Hu Jinhua , Hao Xiaoli , Qu Huaidi
Published: March 2020

During the production process in mines, large amounts of dusts are produced. The dusts pose a potential hazard to the health and safety of miners. Traditional dust removal methods, such as ventilation, water sprays and foam technology, cannot completely solve the problem of dust pollution, due to low efficiency or high consumption of water or large resistance (>2000 Pa). Therefore, a swirling curtain dust collector (SCDC) was proposed to collect the dust in mines. The device was combined swirling atomization with spray curtain for dust removal. The performance of SCDC was investigated. According to the results, the optimum working condition of the device was: air pressure: 0.35 MPa, water volume: 30 L/h; liquid–gas ratio: 0.15 L/m3; air speed: 14–16 m/s. Under these operation parameters, the suppression efficiency of total dust and respirable dust were over 99.8% and 97%. The proposed device was applied at transfer stations of Luohe Metal Mine in Anhui, China. The application results showed that the dust concentration at the outlet of SCDC in the transfer station is lower than 20 mg/m3, which is stipulated by Chinese standard GB 28661-2012. The proposed device is expected to replace the traditional Venturi wet scrubber in mines.
REISCH: Incorporating Lightweight and Reliable Algorithms into Healthcare Applications of WSNs
Authors: Al-Zubaidie Mishall , Zhang Zhongwei , Zhang Ji
Published: March 2020

Healthcare institutions require advanced technology to collect patients’ data accurately and continuously. The tradition technologies still suffer from two problems: performance and security efficiency. The existing research has serious drawbacks when using public-key mechanisms such as digital signature algorithms. In this paper, we propose Reliable and Efficient Integrity Scheme for Data Collection in HWSN (REISCH) to alleviate these problems by using secure and lightweight signature algorithms. The results of the performance analysis indicate that our scheme provides high efficiency in data integration between sensors and server (saves more than 24% of alive sensors compared to traditional algorithms). Additionally, we use Automated Validation of Internet Security Protocols and Applications (AVISPA) to validate the security procedures in our scheme. Security analysis results confirm that REISCH is safe against some well-known attacks.
Antioxidant Activity and Polyphenolic Content of North Macedonian Wines
Authors: Mitrevska Katerina , Grigorakis Spyros , Loupassaki Sofia , Calokerinos Antony C.
Published: March 2020

The purpose of this study was to evaluate comparatively the polyphenolic content and the antioxidant activity of selected regional red and white wine varieties, produced in the Republic of North Macedonia. The polyphenolic content was evaluated by measuring the total polyphenol, total flavonoid, total tannin and total anthocyanin contents and the antioxidant activity by applying the DPPH (2,2-diphenyl-1-picrylhydrazyl), FRAP (ferric-reducing antioxidant power) and CUPRAC (cupric ion-reducing antioxidant capacity) assays. Statistical analysis of the results showed that all white wines examined (Smederevka, Temjanika and Zhilavka) belong to the same group, two red wines (Vranec and Kratoshija) belong to another group while the Stanushina red variety shows distinct differences from the other red wines examined.
Blockchain-Based Secure Data Storage for Distributed Vehicular Networks
Authors: Javed Muhammad Umar , Rehman Mubariz , Javaid Nadeem , Aldegheishem Abdulaziz , Alrajeh Nabil , Tahir Muhammad
Published: March 2020

In this paper, a blockchain-based secure data sharing mechanism is proposed for Vehicular Networks (VNs). Edge service providers are introduced along with ordinary nodes to efficiently manage service provisioning. The edge service providers are placed in the neighborhood of the ordinary nodes to ensure smooth communication between them. The huge amount of data generated by smart vehicles is stored in a distributed file storage system, known as Interplanetary File System (IPFS). It is used to tackle the issues related to data storage in centralized architectures, such as data tampering, lack of privacy, vulnerability to hackers, etc. Monetary incentives are given to edge vehicle nodes to motivate them for accurate and timely service provisioning to ordinary nodes. In response, ordinary nodes give reviews to the edge nodes against the services provided by them, which are further stored in a blockchain to ensure integrity, security and transparency. Smart contracts are used to automate the system processes without the inclusion of an intermediate party and to check the reviews given to the edge nodes. To optimize gas consumption and to enhance the system performance, a Proof of Authority (PoA) consensus mechanism is used to validate the transactions. Moreover, a caching system is introduced at the edge nodes to store frequently used services. Furthermore, both security and privacy are enhanced in the proposed system by incorporating a symmetric key cryptographic mechanism. A trust management mechanism is also proposed in this work to calculate the nodes’ reputation values based upon their trust values. These values determine the authenticity of the nodes involved in the network. Eventually, it is concluded from the simulation results that the proposed system is efficient for VNs.
A Construction Schedule Robustness Measure Based on Improved Prospect Theory and the Copula-CRITIC Method
Authors: Zhao Mengqi , Wang Xiaoling , Yu Jia , Xue Linli , Yang Shuai
Published: March 2020

A robustness measure is an effective tool to evaluate the anti-interference capacity of the construction schedule. However, most research focuses on solution robustness or quality robustness, and few consider a composite robustness criterion, neglecting the bounded rationality of subjective weights and inherent importance and nonlinear intercriteria correlations of objective weights. Therefore, a construction schedule robustness measure based on improved prospect theory and the Copula-criteria importance through intercriteria correlation (CRITIC) method is proposed. Firstly, a composite robustness criterion is established, including start time deviation rs and structural deviation rp for measuring solution robustness from project execution and completion probability rc for measuring quality robustness from the project result. Secondly, bounded rationality is considered, using prospect theory to calculate subjective weights, which is improved by the interval distance formula. Thirdly, the Copula-CRITIC method is proposed to determine objective weights incorporating both inherent importance and nonlinear intercriteria correlations. Finally, an information-entropy-based evidence reasoning method is applied to combine subjective and objective weights together while identifying their validity. An underground power station in China is used for a case study, whose robustness is measured using the proposed methods, single robustness criterion, and composite robustness criterion using traditional weighting methods. The comparison results verify the consistency, representativeness, and advantage of the proposed criterion and methods.
Comparing Graphene Oxide and Reduced Graphene Oxide as Blending Materials for Polysulfone and Polyvinylidene Difluoride Membranes
Authors: Yoon Yeojoon , Kye Homin , Yang Woo Seok , Kang Joon-Wun
Published: March 2020

Graphene is a single atomic plane of graphite, and it exhibits unique electronic, thermal, and mechanical properties. Exfoliated graphene oxide (GO) contains various hydrophilic functional groups, such as hydroxyl, epoxide, and carboxyl groups, that can modify the hydrophobic characteristics of a membrane surface. Though reduced graphene oxide (rGO) has fewer functional groups than GO, its associated sp2 structures and physical properties can be recovered. A considerable amount of research has focused on the use of GO to obtain a pristine graphene material via reduction processes. In this study, polysulfone (PSf) and polyvinylidene fluoride (PVDF) membranes that were blended with GO and rGO, respectively, were fabricated by using the immersion phase inversion method and an n-methylpyrrolidone (NMP) solvent. Results showed that the graphene nanomaterials, GO and rGO, can change the pore morphology (size and structure) of both PSf and PVDF membranes. The optimum content of both was then investigated, and the highest flux enhancement was observed with the 0.10 wt% GO-blended PSf membrane. The presence of functional groups in GO within prepared PSf and PVDF membranes alters the membrane characteristics to hydrophilic. An antifouling test and rejection efficiency evaluation also showed that the 0.10 wt% membrane provided the best performance.
Generation of Monodispersed Spherical Thermosensitive Gels and Their Swelling and Shrinking Behaviors in Aqueous Polymeric Solutions
Authors: Sisworo Raden Rinova , Hasegawa Masato , Nakashima Kousuke , Norimatsu Yu , Tada Yukio
Published: March 2020

This study investigates the factors affecting the formation of monodispersed thermosensitive gels and the parameters influencing the movement of gel particles containing N-isopropyl acrylamide in an aqueous polymeric solution in an upper heating system. Monodispersed thermosensitive gels were generated, and their swelling and shrinking behaviors were observed. The results revealed that continuous-phase flow rate and kinematic viscosity were most influential on the size of the monodispersed thermosensitive gels, which exhibited swelling and shrinking at both low and high temperatures of the polymeric aqueous solution, respectively, and demonstrated negative thermal expansion. In a low-temperature solution, the buoyancy force acting on the gel particles exceeded the gravitational force, because of which the size of the gels increased and the gels to ascended. At higher temperatures, the gels shrank because the gravitational force outweighed the buoyancy force, causing the gels to descend. The gels with a larger diameter tended to have longer durations of vertical movements within the aqueous polymeric solution than the smaller-sized gels; moreover, equilibrium conditions were quickly achieved by the smaller gels.
Monitoring of Grouting Compactness in Tendon Duct Using Multi-Sensing Electro-Mechanical Impedance Method
Authors: Guo Bin , Chen Dongdong , Huo Linsheng , Song Gangbing
Published: March 2020

The structural integrity of post-tensioning prestressed concrete structures with tendon ducts highly depends on the grouting quality in construction. This paper proposes a real-time approach to monitoring the grouting compactness in tendon ducts using the multi-sensing electro-mechanical impedance (EMI) method. When Lead Zirconate Titanate (PZT) transducers with different pre-selected dimensions are serially connected and mounted on a structure at distributed locations, each PZT provides unique resonance frequency coupled with the local structural physical property. Therefore, the impedance with multiple peaks of the serially connected multiple PZTs can be captured during a single measurement, which significantly simplifies the measurement procedure and reduces the data processing time. In addition, the wiring for the PZT sensors is also simplified. In this research, the feasibility of the proposed method was experimentally and numerically investigated to monitor the grouting compactness in a tendon duct specimen. The 3-dB mean absolute percentage deviation (MAPD) was applied to quantify the variations of the impedance signatures measured from five different grouting levels. Both experimental and numerical results verify the feasibility of using the proposed method for monitoring the grouting compactness in tendon ducts.
A Numerical Assessment on the Influences of Material Toughness on the Crashworthiness of a Composite Fuselage Barrel
Authors: Riccio A. , Saputo S. , Sellitto A. , Di Caprio F.
Published: March 2020

In the present work, a numerical study on the dynamic response of a composite fuselage barrel, in relation to crashworthiness, has been investigated. The aim of this work is to investigate the influence of the material fracture toughness on the capability of a composite fuselage barrel to tolerate an impact on a rigid surface. Three different material configurations with different intra-laminar fracture energy values were considered to take into account variations in material toughness. Indeed, the dynamic behaviour of the analysed fuselage barrel has been numerically simulated by means of the FE (Finite Element) code Abaqus/Explicit. The effects of intralaminar fracture energy variations on the impact deformation of the barrel has been evaluated comparing the numerical results in terms of displacements and damage evolution for the three analysed material configurations.
Transfer Learning with Convolutional Neural Networks for Diabetic Retinopathy Image Classification. A Review
Authors: Kandel Ibrahem , Castelli Mauro
Published: March 2020

Diabetic retinopathy (DR) is a dangerous eye condition that affects diabetic patients. Without early detection, it can affect the retina and may eventually cause permanent blindness. The early diagnosis of DR is crucial for its treatment. However, the diagnosis of DR is a very difficult process that requires an experienced ophthalmologist. A breakthrough in the field of artificial intelligence called deep learning can help in giving the ophthalmologist a second opinion regarding the classification of the DR by using an autonomous classifier. To accurately train a deep learning model to classify DR, an enormous number of images is required, and this is an important limitation in the DR domain. Transfer learning is a technique that can help in overcoming the scarcity of images. The main idea that is exploited by transfer learning is that a deep learning architecture, previously trained on non-medical images, can be fine-tuned to suit the DR dataset. This paper reviews research papers that focus on DR classification by using transfer learning to present the best existing methods to address this problem. This review can help future researchers to find out existing transfer learning methods to address the DR classification task and to show their differences in terms of performance.
Evaluation of Smart Alarm Systems for Industry 4.0 Technologies
Authors: Chang Che-Wei
Published: March 2020

Traditionally, the footwear industry is labor intensive, and cost control is key to ensuring shoe companies can be competitive. The development of Industry 4.0 concepts, used in high-tech industries and blockchain production information systems, enables the creation of smart factories with online alarm management systems, to improve manufacturing efficiency and reduce human resource requirements. In this paper, the performances of the causal association assessment model and the technique for order preference by similarity to the ideal solution (TOPSIS) model in evaluating large data blockchain technologies and quality online real-time early warning systems for production and raw material supplier management are compared, to increase the intelligence of production and to manage product traceability.
Pneumatically Actuated Microfluidic Platform for Reconstituting 3D Vascular Tissue Compression
Authors: Ahn Jungho , Lee Hyeok , Kang Habin , Choi Hyeri , Son Kyungmin , Yu James , Lee Jungseub , Lim Jungeun , Park Dohyun , Cho Maenghyo , Jeon Noo Li
Published: March 2020

In vivo, blood vessels constitutively experience mechanical stresses exerted by adjacent tissues and other structural elements. Vascular collapse, a structural failure of vascular tissues, may stem from any number of possible compressive forces ranging from injury to tumor growth and can promote inflammation. In particular, endothelial cells are continuously exposed to varying mechanical stimuli, internally and externally, resulting in blood vessel deformation and injury. This study proposed a method to model biomechanical-stimuli-induced blood vessel compression in vitro within a polydimethylsiloxane (PDMS) microfluidic 3D microvascular tissue culture platform with an integrated pneumatically actuated compression mechanism. 3D microvascular tissues were cultured within the device. Histological reactions to compressive forces were quantified and shown to be the following: live/dead assays indicated the presence of a microvascular dead zone within high-stress regions and reactive oxygen species (ROS) quantification exhibited a stress-dependent increase. Fluorescein isothiocyanate (FITC)-dextran flow assays showed that compressed vessels developed structural failures and increased leakiness; finite element analysis (FEA) corroborated the experimental data, indicating that the suggested model of vascular tissue deformation and stress distribution was conceptually sound. As such, this study provides a powerful and accessible in vitro method of modeling microphysiological reactions of microvascular tissues to compressive stress, paving the way for further studies into vascular failure as a result of external stress.
Putative Receptors for Gravity Sensing in Mammalian Cells: The Effects of Microgravity
Authors: Aventaggiato Michele , Barreca Federica , Vernucci Enza , Bizzarri Mariano , Ferretti Elisabetta , Russo Matteo A. , Tafani Marco
Published: March 2020

Gravity is a constitutive force that influences life on Earth. It is sensed and translated into biochemical stimuli through the so called “mechanosensors”, proteins able to change their molecular conformation in order to amplify external cues causing several intracellular responses. Mechanosensors are widely represented in the human body with important structures such as otholiths in hair cells of vestibular system and statoliths in plants. Moreover, they are also present in the bone, where mechanical cues can cause bone resorption or formation and in muscle in which mechanical stimuli can increase the sensibility for mechanical stretch. In this review, we discuss the role of mechanosensors in two different conditions: normogravity and microgravity, emphasizing their emerging role in microgravity. Microgravity is a singular condition in which many molecular changes occur, strictly connected with the modified gravity force and free fall of bodies. Here, we first summarize the most important mechanosensors involved in normogravity and microgravity. Subsequently, we propose muscle LIM protein (MLP) and sirtuins as new actors in mechanosensing and signaling transduction under microgravity.
Impact of Cyclic Loading on Shakedown in Cohesive Soils—Simple Hysteresis Loop Model
Authors: Głuchowski Andrzej , Sas Wojciech
Published: March 2020

The objective of this study is to characterize the permanent deformations and to present a mathematical model that enables the prediction of permanent strain during cyclic loading. First, laboratory cyclic triaxial tests are conducted on sandy silty clay samples to gather the data concerning the permanent deformation characteristics. The article discusses the shakedown theory and abation phenomena, and we present the Simple Hysteresis Loop Model (SHLM) based on the stress-controlled test results. The determined permanent deformation properties are a base for the development of SHLM parameters. The presented model is capable of accurately predicting the permanent deformation characteristics based on the derived parameters from the static tests. The SHLM connects the stress–strain and stiffness properties of cohesive soil, which gives it a great advantage to use it in engineering practice. The derived model was verified based on ex–post comparison to performed cyclic triaxial test. The developed SHLM mean absolute percentage error is equal to 12.18%, which indicates that the developed SHLM has desirable accuracy in the prediction of permanent strain properties in compacted cohesive soils.
Solvent Extraction of Didymium by TBP, Aliquat 336 and HDEHP in The Presence of Ca(NO3)2
Authors: Matveev Petr I. , Petrov Vladimir G.
Published: March 2020

Three commercially available extractants (tri-butyl-phosphate (TBP), di-(2-ethylhexyl)phosphoric acid (HDEHP) and Aliquat 336 (a mixture of quaternary ammonium bases)) were tested for separation of Pr(III) and Nd(III) in both static and dynamic modes. In the case of HDEHP, phase stability and influence of nitric acid were considered. Extraction isotherms were constructed, and influence of water-soluble complexing agents on the separation factor was investigated for Aliquat 336. In the case of TBP, influence of calcium nitrate in aqueous phase on the extraction efficiency was investigated. Model countercurrent experiments were conducted for TBP and Aliquat 336. It was shown that TBP is the best choice due to its high capacity and cation extraction order (Nd > Pr).
Quantitative Fluxes of the Greenhouse Gases CH4 and CO2 from the Surfaces of Selected Polish Reservoirs
Authors: Gruca-Rokosz Renata
Published: March 2020

Research carried out in the years 2009–2011 and 2018–2019 sought to determine the magnitudes of fluxes of methane (CH4) and carbon dioxide (CO2) from the surfaces of three eutrophic reservoirs in SE Poland. The “static chamber” method was deployed at five or six stations located along the reservoirs, where the water column at its deepest slightly exceeds 2 m. Obtained values for the fluxes of CH4 varied across a wide (0–2513.48 mmol·m−2·d−1) range, with many of these values therefore exceeding those characteristics for large tropical reservoirs. The reservoirs studied were not found to differ significantly in terms of average CH4 flux, however. Where obtained values for CO2 fluxes in the range from −10.96 to 621.69 mmol·m−2·d−1 were concerned, most fell within the range given for temperate-zone reservoirs, while differences between reservoirs were noted for average values in this case.
The Influence of Meteorology and Air Transport on CO2 Atmospheric Distribution over South Africa
Authors: Ncipha Xolile G. , Sivakumar Venkataraman , Malahlela Oupa E.
Published: March 2020

This paper demonstrates the role of meteorology and air transport in influencing the South African atmospheric CO2 distribution. CO2 data from December 2004 to December 2009 acquired by the Tropospheric Emission Spectrometer (TES) instrument onboard the Aura satellite were used to establish the CO2 vertical distribution at selected regions in South Africa. The Hybrid Single-Particle Lagrangian Integrated Trajectories (HYSPLIT) atmospheric model backward trajectories were used to determine the long-range air transport impacting on South African CO2 atmospheric distribution and to detect the source areas of air masses impacting on South Africa’s atmosphere. The study found that long-range air transport can result in the accumulation or dilution of atmospheric CO2 at various sites in South Africa, depending on the source region and type of air flow. The long-range air transport from different source regions at the upper air level between the 700 and 500 hPa stable layers and the layer above 500 hPa strengthens the inhomogeneity in the vertical distribution of CO2, which is caused by the decoupling effect of the upper air stable layers. This long-range air transport also involves intercontinental air transport.
Selected Metals in Urban Road Dust: Upper and Lower Silesia Case Study
Authors: Rybak Justyna , Wróbel Magdalena , Stefan Bihałowicz Jan , Rogula-Kozłowska Wioletta
Published: March 2020

In this study, urban road dust (URD) samples were collected in two populated agglomerations of Wrocław and Katowice (Lower and Upper Silesia) in Poland. Both the total concentrations of URD-bound Mn, Ni, Cu, Zn, As, Rb, Ba, Cr, Mg, and Al and concentrations of their water-soluble fraction were determined. The contamination characteristics and health risk related to these elements were assessed. Contamination level assessment was done by Pollution Load Index (PLI), which indicated much higher pollution of Katowice agglomeration than Wrocław. The enrichment factor values (EF) showed that the most elements in both Katowice and Wrocław orginated from anthropogenic sources. The calculations of geo-accumulation index (Igeo) showed that Zn and As are the key pollutants in Katowice; and in the Wrocław region, Cu, Zn, Cr, and Ni are. The principle component analysis (PCA) and correlation analysis provide information about the potential sources of metals. Additionally, a positive matrix factorization (PMF) was performed and four factors in PMF analysis were found and then interpreted by comparing to the source profiles. Three contamination sources were revealed: fossil fuel combustion, road traffic and industrial emissions. Although the main source of studied metals in Lower Silesia is road traffic, in Upper Silesia, domestic heating with the use of hard and brawn coal and industrial activity predominates. Human exposure to individual toxic metals through road dust was assessed for both children and adults. By calculating the average daily dose (ADD) via ingestion, inhalation, and dermal contact, it was found that ingestion and then dermal contact were the greatest exposure pathways for humans in Katowice and Wrocław. Children had greater health risks than adults. According to the health risk assessment, the overall non-carcinogenic risks in both urban areas was rather low. The only exception was As bound to urban road dust in Katowice agglomeration, which indicates risk for children when ingested. The total excess cancer risk (ECR) was also lower than the acceptable level (10−6–10−4) for both adults and children, although ECR for Katowice was closer to this limit.
Electrospun Al2O3 Film as Inhibiting Corrosion Interlayer of Anode for Solid Aluminum–Air Batteries
Authors: Zuo Yuxin , Yu Ying , Liu Hao , Gu Zhiqing , Cao Qianqian , Zuo Chuncheng
Published: March 2020

Solid Al–air batteries are a promising power source for potable electronics due to their environmentally friendly qualities and high energy density. However, the solid Al–air battery suffers from anodic corrosion and it is difficult to achieve a higher specific capacity. Thus, this work aims at suppressing the corrosion of Al anode by adding an electrospun Al2O3 interlayer on to the surface of the anode. The Al2O3 interlayer effectively inhibits the self-corrosion of the Al anode. Further, the effects of the thickness of the Al2O3 film on corrosion behavior were investigated. The results showed that the Al–air battery with a 4 μm Al2O3 interlayer is more suitable for a low current density discharge, which could be applied for mini-watt devices. With a proper thickness of the Al2O3 interlayer, corrosion of the anode was considerably suppressed without sacrificing the discharge voltage at a low current density. The Al–air battery with a 4 μm Al2O3 interlayer provided a significantly high capacity (1255 mAh/g at 5 mA/cm2) and an excellent stability. This wo presents a promising approach for fabricating an inhibiting corrosion interlayer for solid Al–air battery designed for mini-watt devices.
Molecular Imaging of Galectin-1 Expression as a Biomarker of Papillary Thyroid Cancer by Using Peptide-Functionalized Imaging Probes
Authors: Fanfone Deborah , Stanicki Dimitri , Nonclercq Denis , Port Marc , Vander Elst Luce , Laurent Sophie , Muller Robert N. , Saussez Sven , Burtea Carmen
Published: March 2020

Thyroid cancers are the most frequent endocrine cancers and their incidence is increasing worldwide. Thyroid nodules occur in over 19–68% of the population, but only 7–15% of them are diagnosed as malignant. Diagnosis relies on a fine needle aspiration biopsy, which is often inconclusive and about 90% of thyroidectomies are performed for benign lesions. Galectin-1 has been proposed as a confident biomarker for the discrimination of malignant from benign nodules. We previously identified by phage display two peptides (P1 and P7) targeting galectin-1, with the goal of developing imaging probes for non-invasive diagnosis of thyroid cancer. The peptides were coupled to ultra-small superparamagnetic particles of iron oxide (USPIO) or to a near-infrared dye (CF770) for non-invasive detection of galectin-1 expression in a mouse model of papillary thyroid cancer (PTC, as the most frequent one) by magnetic resonance imaging and fluorescence lifetime imaging. The imaging probes functionalized with the two peptides presented comparable image enhancement characteristics. However, those coupled to P7 were more favorable, and showed decreased retention by the liver and spleen (known for their galectin-1 expression) and high sensitivity (75%) and specificity (100%) of PTC detection, which confirm the aptitude of this peptide to discriminate human malignant from benign nodules (80% sensitivity, 100% specificity) previously observed by immunohistochemistry.
Ex Vivo Rat Transected Spinal Cord Slices as a Model to Assess Lentiviral Vector Delivery of Neurotrophin-3 and Short Hairpin RNA against NG2
Authors: Patar Azim , Dockery Peter , McMahon Siobhan , Howard Linda
Published: March 2020

The failure of the spinal cord to regenerate can be attributed both to a lack of trophic support for regenerating axons and to upregulation of inhibitory factors such as chondroitin sulphate proteoglycans including NG2 following injury. Lentiviral vector-mediated gene therapy is a possible strategy for treating spinal cord injury (SCI). This study investigated the effect of lentiviral vectors expressing Neurotrophin-3 (NT-3) and short-hairpin RNA against NG2 (NG2 sh) to enhance neurite outgrowth in in vitro and ex vivo transection injury models. Conditioned medium from cells transduced with NT-3 or shNG2 lentiviruses caused a significant increase in neurite length of primary dorsal root ganglia neurons compared to the control group in vitro. In an ex vivo organotypic slice culture (OSC) transduction with Lenti-NT-3 promoted axonal growth. Transducing OSCs with a combination of Lenti-NT-3/NG2 sh lead to a further increase in axonal growth but only in injured slices and only within the region adjacent to the site of injury. These findings suggest that the combination of lentiviral NT-3 and NG2 sh reduced NG2 levels and provided a more favourable microenvironment for neuronal regeneration after SCI. This study also shows that OSCs may be a useful platform for studying glial scarring and potential SCI treatments.
Metatranscriptomic and Metagenomic Analysis of Biological Diversity in Subglacial Lake Vostok (Antarctica)
Authors: Gura Colby , Rogers Scott O.
Published: March 2020

A combined metatranscriptomic and metagenomic study of Vostok (Antarctica) ice core sections from glacial, basal, and lake water accretion ice yielded sequences that indicated a wide variety of species and possible conditions at the base of the glacier and in subglacial Lake Vostok. Few organisms were in common among the basal ice and accretion ice samples, suggesting little transmission of viable organisms from the basal ice meltwater into the lake water. Additionally, samples of accretion ice, each of which originated from water in several locations of the shallow embayment, exhibit only small amounts of mixing of species. The western-most portion of the embayment had very low numbers of organisms, likely due to biologically challenging conditions. Increasing numbers of organisms were found progressing from west to east, up to approximately 7 km into the embayment. At that point, the numbers of unique sequences and sequence reads from thermophilic, thermotolerant, psychrophilic, and psychrotolerant organisms increased dramatically, as did sequences from alkaliphilic, alkalitolerant, acidophilic, and acidotolerant sequences. The number of unique and total sequences were positively associated with increases in concentrations of Na+, Ca2+, Mg2+, SO42−, Cl−, total amino acids, and non-purgeable organic carbon. The numbers of unique sequences from organisms reported from soil, sediment, ice, aquatic, marine, animal, and plant (probably pollen) sources also peaked in this region, suggesting that this was the most biologically active region. The confluence of the high numbers of organisms, physiologies, and metabolic capabilities suggests the presence of energy and nutrient sources in the eastern half of the embayment. Data from the main basin suggested a cold oligotrophic environment containing fewer organisms. In addition to bacteria, both the basal ice and accretion ice contained sequences from a diverse assemblage of eukaryotes, as well as from bacteria that are known to be associated with multicellular eukaryotes.
Aptamers Increase Biocompatibility and Reduce the Toxicity of Magnetic Nanoparticles Used in Biomedicine
Authors: Zamay Galina S. , Zamay Tatiana N. , Lukyanenko Kirill A. , Kichkailo Anna S.
Published: March 2020

Aptamer-based approaches are very promising tools in nanomedicine. These small single-stranded DNA or RNA molecules are often used for the effective delivery and increasing biocompatibility of various therapeutic agents. Recently, magnetic nanoparticles (MNPs) have begun to be successfully applied in various fields of biomedicine. The use of MNPs is limited by their potential toxicity, which depends on their biocompatibility. The functionalization of MNPs by ligands increases biocompatibility by changing the charge and shape of MNPs, preventing opsonization, increasing the circulation time of MNPs in the blood, thus shielding iron ions and leading to the accumulation of MNPs only in the necessary organs. Among various ligands, aptamers, which are synthetic analogs of antibodies, turned out to be the most promising for the functionalization of MNPs. This review describes the factors that determine MNPs’ biocompatibility and affect their circulation time in the bloodstream, biodistribution in organs and tissues, and biodegradation. The work also covers the role of the aptamers in increasing MNPs’ biocompatibility and reducing toxicity.
Cancer Vaccines and Oncolytic Viruses Exert Profoundly Lower Side Effects in Cancer Patients than Other Systemic Therapies: A Comparative Analysis
Authors: Schirrmacher Volker
Published: March 2020

This review compares cytotoxic drugs, targeted therapies, and immunotherapies with regard to mechanisms and side effects. Targeted therapies relate to small molecule inhibitors. Immunotherapies include checkpoint inhibitory antibodies, chimeric antigen receptor (CAR) T-cells, cancer vaccines, and oncolytic viruses. All these therapeutic approaches fight systemic disease, be it micro-metastatic or metastatic. The analysis includes only studies with a proven therapeutic effect. A clear-cut difference is observed with regard to major adverse events (WHO grades 3–4). Such severe side effects are not observed with cancer vaccines/oncolytic viruses while they are seen with all the other systemic therapies. Reasons for this difference are discussed.
A Label-Free Immunosensor Based on Graphene Oxide/Fe3O4/Prussian Blue Nanocomposites for the Electrochemical Determination of HBsAg
Authors: Wei Shanshan , Xiao Haolin , Cao Liangli , Chen Zhencheng
Published: March 2020

In this article, a highly sensitive label-free immunosensor based on a graphene oxide (GO)/Fe3O4/Prussian blue (PB) nanocomposite modified electrode was developed for the determination of human hepatitis B surface antigen (HBsAg). In this electrochemical immunoassay system, PB was used as a redox probe, while GO/Fe3O4/PB nanocomposites and AuNPs were prepared and coated on screen-printed electrodes to enhance the detection sensitivity and to immobilize the hepatitis B surface antibody (HBsAb). The immunosensor was fabricated based on the principle that the decrease in peak currents of PB is proportional to the concentration of HBsAg captured on the modified immunosensor. The experimental results revealed that the immunosensor exhibited a sensitive response to HBsAg in the range of 0.5 pg·mL−1 to 200 ng·mL−1, and with a low detection limit of 0.166 pg·mL−1 (S/N = 3). Furthermore, the proposed immunosensor was used to detect several clinical serum samples with acceptable results, and it also showed good reproducibility, selectivity and stability, which may have a promising potential application in clinical immunoassays.
Recyclable SERS-Based Immunoassay Guided by Photocatalytic Performance of Fe3O4@TiO2@Au Nanocomposites
Authors: Du Yuanyuan , Liu Hongmei , Tian Yiran , Gu Chenjie , Zhao Ziqi , Zeng Shuwen , Jiang Tao
Published: March 2020

A novel recyclable surface-enhanced Raman scattering (SERS)-based immunoassay was demonstrated and exhibited extremely high sensitivity toward prostate specific antigen (PSA). The immunoassay, which possessed a sandwich structure, was constructed of multifunctional Fe3O4@TiO2@Au nanocomposites as immune probe and Ag-coated sandpaper as immune substrate. First, by adjusting the density of outside Au seeds on Fe3O4@TiO2 core-shell nanoparticles (NPs), the structure-dependent SERS and photocatalytic performance of the samples was explored by monitoring and degradating 4-mercaptobenzonic acid (4MBA). Afterwards, the SERS enhancement capability of Ag-coated sandpaper with different meshes was investigated, and a limit of detection (LOD), as low as 0.014 mM, was achieved by utilizing the substrate. Subsequently, the recyclable feasibility of PSA detection was approved by zeta potential measurement, absorption spectra, and SEM images and, particularly, more than 80% of SERS intensity still existed after even six cycles of immunoassay. The ultralow LOD of the recyclable immunoassay was finally calculated to be 1.871 pg/mL. Therefore, the recyclable SERS-based immunoassay exhibits good application prospects for diagnosis of cancer in clinical measurements.
No Longer Underappreciated: The Emerging Concept of Astrocyte Heterogeneity in Neuroscience
Authors: Pestana Francisco , Edwards-Faret Gabriela , Belgard T. Grant , Martirosyan Araks , Holt Matthew G.
Published: March 2020

Astrocytes are ubiquitous in the central nervous system (CNS). These cells possess thousands of individual processes, which extend out into the neuropil, interacting with neurons, other glia and blood vessels. Paralleling the wide diversity of their interactions, astrocytes have been reported to play key roles in supporting CNS structure, metabolism, blood-brain-barrier formation and control of vascular blood flow, axon guidance, synapse formation and modulation of synaptic transmission. Traditionally, astrocytes have been studied as a homogenous group of cells. However, recent studies have uncovered a surprising degree of heterogeneity in their development and function, in both the healthy and diseased brain. A better understanding of astrocyte heterogeneity is urgently needed to understand normal brain function, as well as the role of astrocytes in response to injury and disease.
Design Fluency in Children with ADHD and Comorbid Disorders
Authors: Fournier Anaïs , Gauthier Bruno , Guay Marie-Claude , Parent Véronique
Published: March 2020

Background: Attention deficit/hyperactivity disorder (ADHD) is often associated with frontal executive impairment in children. Oppositional defiant disorder (ODD) and anxiety disorders (AD) frequently accompany ADHD, but the impact of these comorbid disorders on cognition remains elusive. The five-point test (FPT), a design fluency task, has been shown to be sensitive to neurological damage, specifically to frontal lobe lesions in patients with brain injuries. The purpose of this study was to compare the performances of neurotypical children with that of children with ADHD, ADHD-ODD, and ADHD-AD on the FPT in order to examine whether these groups could be distinguished from one another based on their cognitive profile. Methods: A total of 111 children aged 8 to 11 years old participated in the study. Six measures from the FPT were used to characterize their performance. Results: Statistically significant differences between groups were observed for five of the six FPT measures. Essentially, children with ADHD-ODD made more repeated designs than the three other groups (control p > 0.001, ADHD p = 0.008, ADHD-AD p = 0.008), while children with ADHD-AD produced fewer total and correct designs than the control and ADHD groups (p = 0.009). Conclusions: This suggests that comorbidities have an additive impact on the cognitive profile of children with ADHD. Design fluency may be a sensitive measure for capturing the subtle cognitive deficits that are likely to be involved in these disorders.