bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of 3D Printing for the Development of Biodegradable Antiplatelet Materials for Cardiovascular Applications
Authors: Domínguez-Robles Juan , Diaz-Gomez Luis , Utomo Emilia , Shen Tingjun , Picco Camila J. , Alvarez-Lorenzo Carmen , Concheiro Angel , Donnelly Ryan F. , Larrañeta Eneko
Published: September 2021

Small-diameter synthetic vascular grafts are required for surgical bypass grafting when there is a lack of suitable autologous vessels due to different reasons, such as previous operations. Thrombosis is the main cause of failure of small-diameter synthetic vascular grafts when used for this revascularization technique. Therefore, the development of biodegradable vascular grafts capable of providing a localized and sustained antithrombotic drug release mark a major step forward in the fight against cardiovascular diseases, which are the leading cause of death globally. The present paper describes the use of an extrusion-based 3D printing technology for the production of biodegradable antiplatelet tubular grafts for cardiovascular applications. For this purpose, acetylsalicylic acid (ASA) was chosen as a model molecule due to its antiplatelet activity. Poly(caprolactone) and ASA were combined for the fabrication and characterization of ASA-loaded tubular grafts. Moreover, rifampicin (RIF) was added to the formulation containing the higher ASA loading, as a model molecule that can be used to prevent vascular prosthesis infections. The produced tubular grafts were fully characterized through multiple techniques and the last step was to evaluate their drug release, antiplatelet and antimicrobial activity and cytocompatibility. The results suggested that these materials were capable of providing a sustained ASA release for periods of up to 2 weeks. Tubular grafts containing 10% (w/w) of ASA showed lower platelet adhesion onto the surface than the blank and grafts containing 5% (w/w) of ASA. Moreover, tubular grafts scaffolds containing 1% (w/w) of RIF were capable of inhibiting the growth of Staphylococcus aureus. Finally, the evaluation of the cytocompatibility of the scaffold samples revealed that the incorporation of ASA or RIF into the composition did not compromise cell viability and proliferation at short incubation periods (24 h).
Microstructure and Electrical Properties of Fluorene Polyester Based Nanocomposite Dielectrics
Authors: Zhang Wenchao , Zhao Kuo , Guan Feng , Yin Jinghua , Feng Yu , Li Jialong , Li Yanpeng
Published: September 2021

As a new type of dielectric material, the low dielectric constant and corona resistance life of fluorene polyester (FPE) restricts the range of its applications. In order to simultaneously achieve a high dielectric constant and the long corona aging lifetime of FPE, SiO2 nanoparticles were chosen as additive to prepare FPE-based composite films. The microstructure of the composite film was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared spectroscopy (IR) and small-angle X-ray scattering (SAXS). The dielectric performances of the composites, including the dielectric constant, breakdown strength and corona resistance lifetime, were investigated. The results show that the introduced SiO2 does not destroy the structure of the FPE molecular chain and that it increases the thickness of the filler-matrix interface. The dielectric constant of SiO2/FPE composites increased from 3.54 to 7.30 at 1 Hz. Importantly, the corona resistance lifetime increased by about 12 times compared with the pure FPE matrix. In brief, this work shows what possibilities there might be when considering the potential applications of high-strength insulating materials.
Core-Shell Structured Magnetic Carboxymethyl Cellulose-Based Hydrogel Nanosorbents for Effective Adsorption of Methylene Blue from Aqueous Solution
Authors: Zhou Yiming , Li Te , Shen Juanli , Meng Yu , Tong Shuhua , Guan Qingfang , Xia Xinxing
Published: September 2021

This article reports effective removal of methylene blue (MB) dyes from aqueous solutions using a novel magnetic polymer nanocomposite. The core-shell structured nanosorbents was fabricated via coating Fe3O4 nanoparticles with a layer of hydrogel material, that synthesized by carboxymethyl cellulose cross-linked with poly(acrylic acid-co-acrylamide). Some physico-chemical properties of the nanosorbents were characterized by various testing methods. The nanosorbent could be easily separated from aqueous solutions by an external magnetic field and the mass fraction of outer hydrogel shell was 20.3 wt%. The adsorption performance was investigated as the effects of solution pH, adsorbent content, initial dye concentration, and contact time. The maximum adsorption capacity was obtained at neutral pH of 7 with a sorbent dose of 1.5 g L−1. The experimental data of MB adsorption were fit to Langmuir isotherm model and Pseudo-second-order kinetic model with maximum adsorption of 34.3 mg g−1. XPS technique was applied to study the mechanism of adsorption, electrostatic attraction and physically adsorption may control the adsorption behavior of the composite nanosorbents. In addition, a good reusability of 83.5% MB recovering with adsorption capacity decreasing by 16.5% over five cycles of sorption/desorption was observed.
Preparation of a Novel CO2-Responsive Polymer/Multiwall Carbon Nanotube Composite
Authors: Ma Yonggang , Chen Xin , Han Dehui , Zhao Zhe , Lu Wenting
Published: September 2021

A CO2-responsive composite of multiwall carbon nanotube (MWCNT) coated with polydopamine (PDA) and polydimethylamino-ethyl methacrylate (PDMAEMA) was prepared. The PDA was first self-polymerized on the surface of carbon nanotube. 2-bromoisobutyryl bromide (BiBB) was then immobilized by PDA and then initiated the ATRP of DMAEMA on the carbon nanotube surface. The resulting composite was characterized by Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The CO2-responsive test was performed by bubbling CO2 into the mixture of MWCNT-PDA-PDMAEMA composite in water. A well-dispersed solution was obtained and the UV-Vis transmittance decreased dramatically. This is attributed to the reaction between PDMAEMA and CO2. The formation of ammonium bicarbonates on the surface of carbon nanotubes leads to the separation of nanotube bundles. This process can be reversed as the removal of CO2 by bubbling N2.
Capabilities of an Automatic Lidar Ceilometer to Retrieve Aerosol Characteristics within the Planetary Boundary Layer
Authors: Li Dingdong , Wu Yonghua , Gross Barry , Moshary Fred
Published: September 2021

Continuous observation and quantitative retrieval of aerosol backscatter coefficients are important in the study of air quality and climate in metropolitan areas such as New York City. Ceilometers are ideal for this application, but aerosol backscatter coefficient retrievals from ceilometers are challenging and require proper calibration. In this study, we calibrate the ceilometer (Lufft CHM15k, 1064 nm) system constant with the molecular backscatter coefficient and evaluate the calibrated profiles with other independent methods, including the water-phase cloud method and comparison with the NASA Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) attenuated backscatter coefficient profile. Multiple-day calibration results show a stable system constant with a relative uncertainty of about 7%. We also evaluate the overlap correction for the CHM15k ceilometer (provided by Lufft) with a Vaisala CL-31 ceilometer, and the results show good consistency between two ceilometers’ range-corrected signal (RCS) profiles above 200 m. Next, we implement a forward iterative method to retrieve aerosol backscatter coefficients from continuous ceilometer measurements. In the retrieval, the lidar ratio is constrained by the co-located NASA AERONET radiometer aerosol optical depth (AOD) retrieval and agrees with the AERONET lidar-ratio products, derived from aerosol microphysical parameters. The aerosol backscatter coefficient retrievals are validated with co-located elastic-Raman lidar retrievals and indicate a good correlation (R2≥0.95) in the planetary boundary layer (PBL). Furthermore, a case study shows that the ceilometer retrieved aerosol extinction coefficient profiles can be used to estimate the AOD of the PBL and the aloft plumes. Finally, simulations of the uncertainty of aerosol backscatter coefficient retrieval show that a calibration error of 10% results in 10–20% of relative error in the aerosol backscatter coefficient retrievals, while relative error caused by a lidar-ratio error of 10% is less than 4% in the PBL.
GIS-Based Landslide Susceptibility Mapping of the Circum-Baikal Railway in Russia Using UAV Data
Authors: Gantimurova Svetlana , Parshin Alexander , Erofeev Vladimir
Published: September 2021

The investigation of hard-to-reach areas that are prone to landslides is challenging. The research of landslide hazards can be significantly advanced by using remote sensing data obtained from an unmanned aerial vehicle (UAV). Operational acquisition and high detail are the advantages of UAV data. The development of appropriate automated algorithms and software solutions is necessary for quick decision-making based on the received heterogeneous spatial data characterising various aspects of the environment. This article introduces the first phase of a long-term study about landslide detection and prediction that aims to develop an automatic algorithm for detecting potentially hazardous landslide areas, using data obtained by UAV surveys. As a part of the project, the selection of appropriate techniques was implemented and a landslide susceptibility (LS) map of the study site was developed. This paper presents the outcomes of the applied indirect heuristic approach of landslide susceptibility assessment using an analytical hierarchy process (AHP) in a GIS environment, based on UAV data. The results obtained have been tested on a real-world entity.
Spatial Downscaling of Land Surface Temperature over Heterogeneous Regions Using Random Forest Regression Considering Spatial Features
Authors: Tang Kai , Zhu Hongchun , Ni Ping
Published: September 2021

Land surface temperature (LST) is one of the crucial parameters in the physical processes of the Earth. Acquiring LST images with high spatial and temporal resolutions is currently difficult because of the technical restriction of satellite thermal infrared sensors. Downscaling LST from coarse to fine spatial resolution is an effective means to alleviate this problem. A spatial random forest downscaling LST method (SRFD) was proposed in this study. Abundant predictor variables—including land surface reflection data, remote sensing spectral indexes, terrain factors, and land cover type data—were considered and applied for feature selection in SRFD. Moreover, the shortcoming of only focusing on information from point-to-point in previous statistics-based downscaling methods was supplemented by adding the spatial feature of LST. SRFD was applied to three different heterogeneous regions and compared with the results from three classical or excellent methods, including thermal image sharpening algorithm, multifactor geographically weighted regression, and random forest downscaling method. Results show that SRFD outperforms other methods in vision and statistics due to the benefits from the supplement of the LST spatial feature. Specifically, compared with RFD, the second-best method, the downscaling results of SRFD are 10% to 24% lower in root-mean-square error, 5% to 20% higher in the coefficient of determination, 11% to 25% lower in mean absolute error, and 4% to 17% higher in structural similarity index measure. Hence, we conclude that SRFD will be a promising LST downscaling method.
Integration and Prototyping of a Pulsed RF Oscillator with an UWB Antenna for Low-Cost, Low-Power RTLS Applications
Authors: Bottigliero Stefano , Maggiora Riccardo
Published: September 2021

The goal of this paper is to present a compact low-cost and low-power prototype of a pulsed Ultra Wide Band (UWB) oscillator and an UWB elliptical dipole antenna integrated on the same Radio Frequency (RF) Printed Circuit Board (PCB) and its digital control board for Real Time Locating System (RTLS) applications. The design is compatible with IEEE 802.15.4 high rate pulse repetition UWB standard being able to work between 6 GHz and 8.5 GHz with 500 MHz bandwidth and with a pulse duration of 2 ns. The UWB system has been designed using the CST Microwave Studio transient Electro-Magnetic (EM) circuit co-simulation method. This method integrates the functional circuit simulation together with the full wave (EM) simulation of the PCB’s 3D model allowing fast parameter tuning. The PCB has been manufactured and the entire system has been assembled and measured. Simulated and measured results are in excellent agreement with respect to the radiation performances as well as the power consumption. A compact, very low-power and low-cost system has been designed and validated.
Advanced Bioelectrical Signal Processing Methods: Past, Present, and Future Approach—Part III: Other Biosignals
Authors: Martinek Radek , Ladrova Martina , Sidikova Michaela , Jaros Rene , Behbehani Khosrow , Kahankova Radana , Kawala-Sterniuk Aleksandra
Published: September 2021

Analysis of biomedical signals is a very challenging task involving implementation of various advanced signal processing methods. This area is rapidly developing. This paper is a Part III paper, where the most popular and efficient digital signal processing methods are presented. This paper covers the following bioelectrical signals and their processing methods: electromyography (EMG), electroneurography (ENG), electrogastrography (EGG), electrooculography (EOG), electroretinography (ERG), and electrohysterography (EHG).
Hierarchical Pooling in Graph Neural Networks to Enhance Classification Performance in Large Datasets
Authors: Pham Hai Van , Thanh Dat Hoang , Moore Philip
Published: September 2021

Deep learning methods predicated on convolutional neural networks and graph neural networks have enabled significant improvement in node classification and prediction when applied to graph representation with learning node embedding to effectively represent the hierarchical properties of graphs. An interesting approach (DiffPool) utilises a differentiable graph pooling technique which learns ‘differentiable soft cluster assignment’ for nodes at each layer of a deep graph neural network with nodes mapped on sets of clusters. However, effective control of the learning process is difficult given the inherent complexity in an ‘end-to-end’ model with the potential for a large number parameters (including the potential for redundant parameters). In this paper, we propose an approach termed FPool, which is a development of the basic method adopted in DiffPool (where pooling is applied directly to node representations). Techniques designed to enhance data classification have been created and evaluated using a number of popular and publicly available sensor datasets. Experimental results for FPool demonstrate improved classification and prediction performance when compared to alternative methods considered. Moreover, FPool shows a significant reduction in the training time over the basic DiffPool framework.
Wide Two-Degree-of-Freedom Static Laser Scanner with Miniaturized Transmission Mechanism and Piezoelectric Actuation
Authors: Ozaki Takashi , Ohta Norikazu , Fujiyoshi Motohiro
Published: September 2021

In recent years, laser scanners have attracted significant attention for applications such as laser radars. However, the establishment of a two-degree-of-freedom scanner that can quasi-statically drive a large mirror with a large deflection angle has proven to be challenging. In this paper, we propose a laser scanner design and fabrication method by combining two unimorph piezoelectric actuators composed of piezoelectric single-crystal Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 and a miniature translation-rotation conversion mechanism with flexible polyimide hinges. The size of the entire scanner was 32 mm × 12 mm × 10 mm. We successfully demonstrated that the scanner could achieve a large quasi-static mechanical deflection angle amplitude of 20.5° in two axes with a 6-mm-square mirror.
Motion Sensor-Based Detection of Outlier Days Supporting Continuous Health Assessment for Single Older Adults
Authors: Mertens Marc , Debard Glen , Davis Jesse , Devriendt Els , Milisen Koen , Tournoy Jos , Croonenborghs Tom , Vanrumste Bart
Published: September 2021

The aging population has resulted in interest in remote monitoring of elderly individuals’ health and well being. This paper describes a simple unsupervised monitoring system that can automatically detect if an elderly individual’s pattern of presence deviates substantially from the recent past. The proposed system uses a small set of low-cost motion sensors and analyzes the produced data to establish an individual’s typical presence pattern. Then, the algorithm uses a distance function to determine whether the individual’s observed presence for each day significantly deviates from their typical pattern. Empirically, the algorithm is validated on both synthetic data and data collected by installing our system in the residences of three older individuals. In the real-world setting, the system detected, respectively, five, four, and one deviating days in the three locations. The deviating days detected by the system could result from a health issue that requires attention. The information from the system can aid caregivers in assessing the subject’s health status and allows for a targeted intervention. Although the system can be refined, we show that otherwise hidden but relevant events (e.g., fall incident and irregular sleep patterns) are detected and reported to the caregiver.
Data Sharing Mechanism of Sensors and Actuators of Industrial IoT Based on Blockchain-Assisted Identity-Based Cryptography
Authors: Meng Yifan , Li Jingzhao
Published: September 2021

The Industrial IoT is one of the key technologies to improve industrial production efficiency. The entire production process usually involves multiple production regions and numerous smart devices (sensors and actuators). The efficiency of the Industrial IoT is limited by this strong coupling relationship between the subsystem and the sensors and actuators. In this paper, to unleash the potential of Industrial IoT, a safe and reliable data sharing mechanism of sensors and actuators is proposed. We deployed distributed identity authentication and data proxy services in various regions. In the device authentication process, we used identity-based encryption algorithms, and we solved the trust problem between different regions by introducing a private blockchain. In addition, we designed the model of device capability (MDC) to describe the device, enabling it to be shared with a standard interface. Finally, we conducted many performance tests on the proposed mechanism. The test results verified the effectiveness and efficiency of the proposed mechanism.
Fault-Adaptive Autonomy in Systems with Learning-Enabled Components
Authors: Stojcsics Daniel , Boursinos Dimitrios , Mahadevan Nagabhushan , Koutsoukos Xenofon , Karsai Gabor
Published: September 2021

Autonomous Cyber-Physical Systems (CPS) must be robust against potential failure modes, including physical degradations and software issues, and are required to self-manage contingency actions for these failures. Physical degradations often have a significant impact on the vehicle dynamics causing irregular behavior that can jeopardize system safety and mission objectives. The paper presents a novel Behavior Tree-based autonomy architecture that includes a Fault Detection and Isolation Learning-Enabled Component (FDI LEC) with an Assurance Monitor (AM) designed based on Inductive Conformal Prediction (ICP) techniques. The architecture implements real-time contingency-management functions using fault detection, isolation and reconfiguration subsystems. To improve scalability and reduce the false-positive rate of the FDI LEC, the decision-making logic provides adjustable thresholds for the desired fault coverage and acceptable risk. The paper presents the system architecture with the integrated FDI LEC, as well as the data collection and training approach for the LEC and the AM. Lastly, we demonstrate the effectiveness of the proposed architecture using a simulated autonomous underwater vehicle (AUV) based on the BlueROV2 platform.
Vivaldi Antenna Arrays Feed by Frequency-Independent Phase Shifter for High Directivity and Gain Used in Microwave Sensing and Communication Applications
Authors: Ghimire Jiwan , Diba Feyisa Debo , Kim Ji-Hoon , Choi Dong-You
Published: September 2021

This paper describes a novel feed system for compact, wideband, high gain six-slot Vivaldi antenna arrays on a single substrate layer using a unique combination of power splitters based on binary T-junction power splitter topology, frequency-independent phase shifter, and a T-branch. The proposed antenna system consists of six Vivaldi antennas, three on the left, and three on the right arm. Each arm connects with T-junction power divider splitter topology, given that the right arm is linked through a frequency-independent phase shifter. Phase shifters ensure that the beam is symmetrical without splitting in a radiating plane so that highly directive radiation patterns occur. The optimal return losses (S-parameters) are well enriched by reforming Vivaldi’s feeding arms and optimizing Vivaldi slots and feeds. A novel feature of our design is that the antenna exhibits the arrangements of a T-junction power splitter with an out-of-phase feeding mechanism in one of the arms, followed by a T-branching feeding to even arrays of proper Vivaldi antenna arrangement contributing high realized gain and front-to-back ratio up to 14.12 dBi and 23.23 dB respectively applicable for not only ultra-wideband (UWB) application, also for sensing and position detecting. The high directivity over the entire UWB frequency band in both higher and lower frequency ranges ensures that the antenna can be used in microwave through-wall imaging along with resolution imaging for ground penetration radar (GPR) applications. The fabricated antenna parameters are in close agreement with the simulated and measured results and are deployed for the detection of targets inside the voids of the concrete brick.
Low-Power Scan Correlation-Aware Scan Cluster Reordering for Wireless Sensor Networks
Authors: Lee Sangjun , Cho Kyunghwan , Kim Jihye , Park Jongho , Lee Inhwan , Kang Sungho
Published: September 2021

Cryptographic circuits generally are used for applications of wireless sensor networks to ensure security and must be tested in a manufacturing process to guarantee their quality. Therefore, a scan architecture is widely used for testing the circuits in the manufacturing test to improve testability. However, during scan testing, test-power consumption becomes more serious as the number of transistors and the complexity of chips increase. Hence, the scan chain reordering method is widely applied in a low-power architecture because of its ability to achieve high power reduction with a simple architecture. However, achieving a significant power reduction without excessive computational time remains challenging. In this paper, a novel scan correlation-aware scan cluster reordering is proposed to solve this problem. The proposed method uses a new scan correlation-aware clustering in order to place highly correlated scan cells adjacent to each other. The experimental results demonstrate that the proposed method achieves a significant power reduction with a relatively fast computational time compared with previous methods. Therefore, by improving the reliability of cryptography circuits in wireless sensor networks (WSNs) through significant test-power reduction, the proposed method can ensure the security and integrity of information in WSNs.
Quality and Oxidative Changes of Minced Cooked Pork Incorporated with Moringa oleifera Leaf and Root Powder
Authors: Lungu Nobuhle S. , Afolayan Anthony J. , Thomas Ronald S. , Idamokoro Emrobowansan M.
Published: September 2021

Consumers are currently demanding meat products produced using natural additives due to their potential health benefits. Consequently, there has been a progressive interest in the search for more natural antioxidant sources. The aim of this study was to evaluate the effect of varying levels of M. oleifera root and leaf powder on the oxidative stability and quality of cooked minced pork during eight days of refrigerated storage at 4 °C. The leaves contained significantly higher (p ˂ 0.05) concentrations of total phenols (50.08 ± 0.01 mg GAE/g), while the roots contained the highest amounts of flavonoids (375.15 ± 0.19 mg QE/g) and proanthocyanidins (132.62 ± 0.4 mg CE/g). Both plant parts demonstrated good 2,2-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2 íazino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical scavenging activity. Minced cooked pork incorporated with M. oleifera leaf and root powder had significantly lower pH and thiobarbituric acid-reactive substances (TBARS) values compared to the control (p < 0.05). The ferric reducing antioxidant power (FRAP) was also significantly higher in the samples that incorporated antioxidants compared to the control (p < 0.05). Findings from this study suggest that M. oleifera leaves and roots are potent antioxidant sources which can be incorporated in meat to improve quality attributes during storage.
Data Mining to Assess Organizational Transparency across Technology Processes: An Approach from IT Governance and Knowledge Management
Authors: Solana-González Pedro , Vanti Adolfo Alberto , García Lorenzo María Matilde , Bello Pérez Rafael E.
Published: September 2021

Information quality and organizational transparency are relevant issues for corporate governance and sustainability of companies, as they contribute to reducing information asymmetry, decreasing risks, and improving the conduct of decision-makers, ensuring an ethical standard of organizational control. This work uses the COBIT framework of IT governance, knowledge management, and machine learning techniques to evaluate organizational transparency considering the maturity levels of technology processes applied in 285 companies of southern Brazil. Data mining techniques have been methodologically applied to analyze the 37 processes in four different domains: Planning and organization, acquisition and implementation, delivery and support, and monitoring. Four learning techniques for knowledge discovery have been used to build a computational model that allowed us to evaluate the organizational transparency level. The results evidence the importance of IT performance monitoring and assessment, and internal control processes in enabling organizations to improve their levels of transparency. These processes depend directly on the establishment of IT strategic plans and quality management, as well as IT risk and project management, therefore an improvement in the maturity of these processes implies an increase in the levels of organizational transparency and their reputational, financial, and accountability impact.
The Effects of Solidarity, Income, and Reliance on the State on Personal Income Tax Preferences. The Case of the Czech Republic
Authors: Cabelkova Inna , Smutka Lubos
Published: September 2021

The current increase in government spending, caused by COVID epidemics and the increasing visibility of leftist political groups in public media, emphasizes the short-term need for sustainable income taxation. In the long run, rising inequality worldwide makes taxation of high-incomes indispensable for sustainable economic development. This paper empirically studies public attitudes on taxation related to income, preferences for solidarity vs. individual performance, and reliance on the state in the Czech Republic. In this Eastern European country, the dichotomies above bear even more importance due to the communist past. We apply the hierarchical regression analysis with smoothing spline transformations to a representative sample of public opinion data (N = 1104, aged 15–95 years, M ± SD: 47.74 ± 17.39; 51.2% women, 18.50% with higher education). The results suggest that income was associated with the perception that taxes for the rich are inadequately high but was unrelated to perceptions of tax adequacy for average and poor groups of respondents. Higher solidarity and reliance on the state were associated with the desire to increase taxation of high-incomes and decrease taxation of poor income groups. Surprisingly, the reliance on the state was associated with a desire to decrease taxation of average-incomes and total taxation while increasing tax progressivity. Preferences for solidarity were associated with higher preferred overall taxation and more tax progressivity. The explanatory powers of preferences for solidarity and reliance on the state in explaining the variation in tax preferences are at least equivalent and, in some cases, twice as large as the explanatory power of the age, gender, education, and income altogether. The results above present new mechanisms that can contribute to sustainable endogenous economic development.
Social Cooperation as a Driver for a Social and Solidarity Focused Approach to the Circular Economy
Authors: Campagnaro Cristian , D’Urzo Marco
Published: September 2021

The circular economy (CE) is currently a very widespread paradigm aimed at addressing the climate crisis. However, its notions seem often to be only focused on technical, industrial and economic growth-centric goals, without practically addressing social problems such as inequality and social exclusion. In this context, type B social cooperation (SC-B) emerges in the Italian context as a type of organisation explicitly aiming at addressing social issues. It has historically fulfilled this mandate by pioneering, among others, “circular” processes in the field of waste management. In doing so, it has consolidated a high level of organizational and management capacity, which has made it an exemplary model capable of innovating the CE discourse and including marginalized people while delivering high-quality environmental services. Through evidence gathered integrating different methods and sources (interviews with social cooperatives, literature review, case study research on filed actions), this paper aims to offer a reading of SC-B as a driver for promoting a social turn of CE and local development. Moving beyond waste management and towards waste reuse, SC-B could play an active role in creating local and regional waste transformation and upcycling chains, capable of creating new employment and inclusion opportunities as well as reducing environmental impacts by processing wastes directly in the territory, shortening their treatment chain.
Strengthening Gender Responsiveness of the Green Climate Fund Ecosystem-Based Adaptation Programme in Namibia
Authors: Angula Margaret Ndapewa , Mogotsi Immaculate , Lendelvo Selma , Aribeb Karl Mutani , Iteta Aina-Maria , Thorn Jessica P. R.
Published: September 2021

Scholars of gender and climate change argue that gender-blind climate change actions could exacerbate existing inequalities and undermine sustained climate change adaptation actions. For this reason, since 2017, the Green Climate Fund placed gender among its key programming prerequisites, making it the first multilateral climate fund to do so worldwide. However, to date, no lessons to inform planned gender-responsive ecosystem-based interventions in Namibia have been drawn from community-based natural resource management. Thus, this paper aims to share key lessons regarding the way in which gender assessment is useful in enhancing equity in an ecosystem-based adaptation programme for the Green Climate Fund. To this end, we conducted in-depth interviews and group discussions in the 14 rural regions of Namibia with 151 participants from 107 community-based natural resource management organisations (73.5:26.5; male:female ratio). The results identified gender imbalances in leadership and decision-making due to intersecting historic inequalities, ethnicity and geography, as well as other socio-cultural factors in local community-based natural resource management institutions. We also identified income disparities and unequal opportunities to diversify livelihoods, gendered differentiated impacts of climate change and meaningful participation in public forums. Overall, the assessment indicates that considering gender analysis at the initiation of a community-based climate change adaptation project is crucial for achieving resilience to climate change, closing the gender gap, building capacity to increase equity and empowering women in resource-dependent environments in Namibia and Sub-Saharan Africa more broadly.
Technical-Tactical Performance from Data Providers: A Systematic Review in Regular Football Leagues
Authors: Otero-Saborido Fernando Manuel , Aguado-Méndez Rubén D. , Torreblanca-Martínez Víctor M. , González-Jurado José Antonio
Published: September 2021

In recent years, the number of technology companies providing data to football teams has multiplied. At first, the provided information focused more on physical fitness parameters, but today, ever more data is being generated on technical-tactical performance. The objective of this study was to review the studies on technical-tactical variables based on the information offered by data providers from every country’s regular elite league championship. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. A total of 31 studies were selected. LaLiga (27.91%) and the Premier League (18.60%) were the most studied competitions. Amisco was the company with the largest number of studies (54.84%). Descriptive studies (58.06%) predominated over comparative (22.58%) and predictive analyses (19.05%). “Style of play”, “contextual variables” (descriptive analysis), and “demarcation” (comparative analysis) were the most used objectives in the 28 studies reviewed.
COVID-19 Pandemic Waves: 4IR Technology Utilisation in Multi-Sector Economy
Authors: Agbehadji Israel Edem , Awuzie Bankole Osita , Ngowi Alfred Beati
Published: September 2021

In this paper, we reviewed the Fourth Industrial Revolution (4IR) technologies applied to waves of the coronavirus disease (COVID-19). COVID-19 is an existential threat that has resulted in an unprecedented loss of lives, disruption of flight schedules, shutdown of businesses and much more. Though several researchers have highlighted the enormous benefits of 4IR technologies in containing the COVID-19 pandemic, the recent waves of the pandemic call for a thorough review of these technological interventions. The cyber-physical space has had its share of the COVID-19 pandemic effect, and through this review, we highlight the salient issues to help policy formulation towards managing the impact of subsequent COVID-19 waves within such environments. Hence, the purpose of this paper is to review the application of 4IR technologies during the COVID-19 pandemic waves and to highlight their shortcomings. Recent research articles were sourced from an online repository and thoroughly reviewed to highlight 4IR technology applications, innovations, shortcomings and multi-sector challenges. The outcome of this review indicates that the second wave of the pandemic resulted in a lower proportion of patients requiring invasive mechanical ventilation and a lower rate of thrombotic events. In addition, it was revealed that the delay between ICU admissions and tracheal intubation was longer in the second wave in the health care sector. Again, the review suggests that 4IR technologies have been utilized across all the sectors including education, businesses, society, manufacturing, healthcare, agriculture and mining. Businesses have revised their service delivery models to include 4IR technologies and avoid physical contacts. In society, digital certificates, among other digital platforms, have been utilized to assist with the movements of persons who have been vaccinated. Manufacturing concerns have also utilized robots in manufacturing to reduce human-to-human physical contact. The mining sector has automated their work processes, utilising smart boots to prevent infection, smart health bands and smart disinfection tunnels or walkthrough sanitization gates in the mining work environment. However, the identified challenges of implementing 4IR technologies include low-skilled workers, data privacy issues, data analysis poverty, data management issues and many more. The boom in 4IR technologies calls for intense legislation on sweeping data privacy for regulated tech companies. These findings hold salient implications for policy formulation towards tackling future pandemic outbreaks.
Sustainable Development of Students’ Assumed Responsibility for Their Own Learning during Participatory Action Research
Authors: Kazlauskienė Aušra , Gaučaitė Ramutė , Cañabate Dolors , Colomer Jordi , Bubnys Remigijus
Published: September 2021

The goal to ensure sustainable development in the education process obliges to create such practices of teaching and learning which would create conditions for individuals to act in complex situations in a sustainable manner. Personalized, perceived responsibility of a learner for one’s own learning becomes important for implementation of sustainable learning. This research is aimed to reveal authentic experiences of school students assuming responsibility for learning, emphasizing prospects of sustainable education development in practice and possibilities for improvement by employing the strategy of participatory action research. The data was collected according to the stages of the chosen action research during lessons on learning to learn. Forty-six school students and two teachers took part in the research. On the basis of content analysis, it was revealed that school students assume the responsibility for learning when it is grounded on cooperation taking place in the dialogue-based culture, where negotiation and creation of opportunities to choose are among the most important strategies making the assumed responsibility relevant. Intervening conditions emerging in the context of the strategies were also identified: making learning experiences relevant, clarity of criteria, attitude towards failure and the self as a major resource of learning, expectations, and goals and feedback of learning. Interacting with each other, prevailing strategies, and intervening conditions act as components of sustainable development of school students’ assumed responsibility for learning.
Wear Characteristics of Cutting Tool in Brittle Removal of a Ductile Meta in High-Speed Machining
Authors: Su Guosheng , Wang Yuhao , Han Zhitao , Zhang Peirong , Zhang Hongxia , Wang Baolin , Liu Zhanqiang
Published: September 2021

The contact stress and heating effect between the cutting tool and workpiece in metal machining is symmetrical. However, the symmetry may be destroyed by changes in the workpiece material mechanical properties, such as ductility. The goal of this study is to reveal the wear characteristics of the cutting tool in machining a ductile metal with the cutting speed at which the metal is embrittled by the high-strain-rate-embrittle effect (HSREE). Orthogonal high-speed turning experiments were carried out. Pure iron type DT8 was cut at different cutting speeds, ranging from 1000 m/min to 9000 m/min. The shape and morphology of the chips obtained in the experiment were observed and analyzed by optical microscope and scanning electron microscope (SEM). Tool wear characteristics at different cutting speeds were observed. It shows that the pure iron becomes completely brittle when the cutting speed is higher than 8000 m/min. On the rake face, the coating of the cutting tool bursts apart and peels off. A matrix crack originates in the cutting edge or rake face and extends to the flank face of the cutting tool. The effects of HSREE on the tool wear is discussed. The findings of this study are helpful for choosing a suitable tool for brittle cutting of the ductile metal pure iron with very high cutting speed and solving the problems in machining due to its high ductility and high stickiness.
Does Symmetry Control Photocatalytic Activity of Titania-Based Photocatalysts?
Authors: Janczarek Marcin , Wei Zhishun , Mogan Tharishinny R. , Wang Lei , Wang Kunlei , Nitta Akio , Ohtani Bunsho , Kowalska Ewa
Published: September 2021

Decahedral anatase particles (DAPs) have been prepared by the gas-phase method, characterized, and analyzed for property-governed photocatalytic activity. It has been found that depending on the reaction systems, different properties control the photocatalytic activity, that is, the particle aspect ratio, the density of electron traps and the morphology seem to be responsible for the efficiency of water oxidation, methanol dehydrogenation and oxidative decomposition of acetic acid, respectively. For the discussion on the dependence of the photocatalytic activity on the morphology and/or the symmetry other titania-based photocatalysts have also been analyzed, that is, octahedral anatase particles (OAP), commercial titania P25, inverse opal titania with and without incorporated gold NPs in void spaces and plasmonic photocatalysts (titania with deposits of gold). It has been concluded that though the morphology governs photocatalytic activity, the symmetry (despite its importance in many cases) rather does not control the photocatalytic performance.
Ciguatoxin-Producing Dinoflagellate Gambierdiscus in the Beibu Gulf: First Report of Toxic Gambierdiscus in Chinese Waters
Authors: Xu Yixiao , He Xilin , Lee Wai Hin , Chan Leo Lai , Lu Douding , Wang Pengbin , Tao Xiaoping , Li Huiling , Yu Kefu
Published: September 2021

Ciguatera poisoning is mainly caused by the consumption of reef fish that have accumulated ciguatoxins (CTXs) produced by the benthic dinoflagellates Gambierdiscus and Fukuyoa. China has a long history of problems with ciguatera, but research on ciguatera causative organisms is very limited, especially in the Beibu Gulf, where coral reefs have been degraded significantly and CTXs in reef fish have exceeded food safety guidelines. Here, five strains of Gambierdiscus spp. were collected from Weizhou Island, a ciguatera hotspot in the Beibu Gulf, and identified by light and scanning electron microscopy and phylogenetic analyses based on large and small subunit rDNA sequences. Strains showed typical morphological characteristics of Gambierdiscus caribaeus, exhibiting a smooth thecal surface, rectangular-shaped 2′, almost symmetric 4″, and a large and broad posterior intercalary plate. They clustered in the phylogenetic tree with G. caribaeus from other locations. Therefore, these five strains belonged to G. caribaeus, a globally distributed Gambierdiscus species. Toxicity was determined through the mouse neuroblastoma assay and ranged from 0 to 5.40 fg CTX3C eq cell−1. The low level of toxicity of G. caribaeus in Weizhou Island, with CTX-contaminated fish above the regulatory level in the previous study, suggests that the long-term presence of low toxicity G. caribaeus might lead to the bioaccumulation of CTXs in fish, which can reach dangerous CTX levels. Alternatively, other highly-toxic, non-sampled strains could be present in these waters. This is the first report on toxic Gambierdiscus from the Beibu Gulf and Chinese waters and will provide a basis for further research determining effective strategies for ciguatera management in the area.
A Validation System for Selection of Bacteriophages against Shiga Toxin-Producing Escherichia coli Contamination
Authors: Necel Agnieszka , Bloch Sylwia , Nejman-Faleńczyk Bożena , Dydecka Aleksandra , Topka-Bielecka Gracja , Węgrzyn Alicja , Węgrzyn Grzegorz
Published: September 2021

Shiga toxin-producing Escherichia coli (STEC) can cause severe infections in humans, leading to serious diseases and dangerous complications, such as hemolytic-uremic syndrome. Although cattle are a major reservoir of STEC, the most commonly occurring source of human infections are food products (e.g., vegetables) contaminated with cow feces (often due to the use of natural fertilizers in agriculture). Since the use of antibiotics against STEC is controversial, other methods for protection of food against contaminations by these bacteria are required. Here, we propose a validation system for selection of bacteriophages against STEC contamination. As a model system, we have employed a STEC-specific bacteriophage vB_Eco4M-7 and the E. coli O157:H7 strain no. 86-24, bearing Shiga toxin-converting prophage ST2-8624 (Δstx2::cat gfp). When these bacteria were administered on the surface of sliced cucumber (as a model vegetable), significant decrease in number viable E. coli cells was observed after 6 h of incubation. No toxicity of vB_Eco4M-7 against mammalian cells (using the Balb/3T3 cell line as a model) was detected. A rapid decrease of optical density of STEC culture was demonstrated following addition of a vB_Eco4M-7 lysate. However, longer incubation of susceptible bacteria with this bacteriophage resulted in the appearance of phage-resistant cells which predominated in the culture after 24 h incubation. Interestingly, efficiency of selection of bacteria resistant to vB_Eco4M-7 was higher at higher multiplicity of infection (MOI); the highest efficiency was evident at MOI 10, while the lowest occurred at MOI 0.001. A similar phenomenon of selection of the phage-resistant bacteria was also observed in the experiment with the STEC-contaminated cucumber after 24 h incubation with phage lysate. On the other hand, bacteriophage vB_Eco4M-7 could efficiently develop in host bacterial cells, giving plaques at similar efficiency of plating at 37, 25 and 12 °C, indicating that it can destroy STEC cells at the range of temperatures commonly used for vegetable short-term storage. These results indicate that bacteriophage vB_Eco4M-7 may be considered for its use in food protection against STEC contamination; however, caution should be taken due to the phenomenon of the appearance of phage-resistant bacteria.
Incidence of Zika Virus Infection from a Dengue Epidemiological Study of Children in Ratchaburi Province, Thailand
Authors: Sriburin Pimolpachr , Sittikul Pichamon , Kosoltanapiwat Nathamon , Sirinam Salin , Arunsodsai Watcharee , Sirivichayakul Chukiat , Limkittikul Kriengsak , Chatchen Supawat
Published: September 2021

Zika virus (ZIKV) is the mosquito-transmitted virus that the WHO declared a Public Health Emergency of International Concern in 2016 due to the consequence of microcephaly from infected pregnancies. The incidence of Zika infection has been unclear in many countries because most infected people have nonspecific febrile illnesses. This study’s aim is to investigate the incidence of symptomatic Zika virus infections from the archived samples of a dengue cohort study of children in central Thailand from 2006 to 2009. We performed Zika NS1 immunoglobulin (Ig)G enzyme-linked immunosorbent assay (ELISA) screening to identify symptomatic Zika infections in paired acute/convalescent serum samples. Symptomatic Zika infections were confirmed by reverse transcription polymerase chain reactions (RT-PCR) of acute serum samples. The comparison of the Zika NS1 IgG ELISA results between acute and convalescent samples showed 290/955 (30.4%) seropositive cases. Zika RT-PCR results were positive in 28 febrile cases (15 females, 13 males). Zika RT-PCR showed that symptomatic Zika infection occurred in children aged 4–11 years in Ratchaburi province, Thailand (2007–2009, first case in April 2007), and the symptomatic Zika:dengue infection ratio was 28 Zika:394 dengue (1:14). Phylogenetic analysis showed that all Zika viruses were of Asian lineage. Zika NS1 IgG ELISA identified Zika-infected patients and showed a low Zika:dengue ratio.