bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing Livelihood Resilience of Artisanal Fisherfolk to the Decline in Small-Scale Fisheries in Ghana
Authors: Amadu Iddrisu , Armah Frederick Ato , Aheto Denis Worlanyo
Published: September 2021

The concept of livelihood resilience provides a unique framework for understanding challenges in complex social–ecological systems (SESs) and fostering sustainability. Despite the crises many small-scale fisheries (SSFs) are facing, few studies have operationalized the concept in the context of declining SSFs in developing countries. This study aims to assess the resilience of artisanal fisherfolk livelihoods and its predicting factors in three fishing communities—Elmina, Jamestown, and Axim—in Ghana. A total of 1180 semi-structured interviews were conducted with fishers, fish processors, and mongers. Descriptive and multivariate statistical techniques were used to analyze the data. The results show that the livelihood resilience of fisherfolk increases with an increased level of education and varies by gender. Male fisherfolk with secondary/post-secondary level education had the highest proportion (50%) of more resilient livelihoods. Only 36% of female fisherfolk with secondary/post-secondary level education had more resilient livelihoods. While 40% of male fisherfolk with no formal education had less resilient livelihoods, the livelihoods of half (51%) of females fisherfolk with no formal education were less resilient. The sociodemographic characteristics including wealth status, dependency ratio, marital status, religion, and ethnicity; contextual factors (community); and other relevant factors (experience in fishing, membership of fisherfolk association/group, and beneficiary of livelihood interventions) were found as predictors of the resilience of fisherfolks livelihoods. The findings suggest that interventions towards improving the livelihood resilience of fisherfolk need to consider individual- and household-level characteristics, as well as contextual factors such as marital status, religious affiliation, ethnicity, wealth status, dependency ratio, community, etc.
Does Music Affect Visitors’ Choices for the Management and Conservation of Ecosystem Services?
Authors: Notaro Sandra , De Salvo Maria
Published: September 2021

Psychological research has long demonstrated that preferences can be influenced by stimuli coming from the environment. Music, as an external stimulus influencing people behaviours, purchasing processes and spending, has been widely analysed in consumer behaviour and marketing literature. Here, we focus on the effect of music genres on preferences and willingness to pay for selected ecosystem services of a Nature Park when they are elicited with a Discrete Choice Experiment. This aspect is important in non-market valuation because music can represent an element of context-dependence for the assessment of individual choices, so that the assumption of preference stability does not hold, and welfare estimates may be biased. The results of a generalized mixed logit model evidenced a significant effect of music on preferences. If elicited preferences depend on the context on which the survey is implemented, wrong information to decision makers is provided when the choice context is altered by an uncontrolled external stimulus. This result is particularly important for applied researchers and policy makers. First, the use of protocols and guidelines that instruct respondents about the ambient background when answering a questionnaire is highly recommended, particularly for online surveys. Second, specific genres of music should be used in educational and ecosystem services conservation campaigns and also piped in visitor centres and virtual tours to encourage nature conservation and improve visitors’ sensitiveness for the environment.
Thermal-Energy Analysis and Life Cycle GHG Emissions Assessments of Innovative Earth-Based Bamboo Plastering Mortars
Authors: Paiva Rayane de Lima Moura , Caldas Lucas Rosse , Martins Adriana Paiva de Souza , de Sousa Patricia Brandão , de Oliveira Giulia Fea , Toledo Filho Romildo Dias
Published: September 2021

Biomaterials and raw earth have demonstrated a promising potential for improving various thermal properties of plastering mortars used in buildings. The objective of this research was the evaluation of the thermal-energy performances and life cycle greenhouse gas (GHG) emissions of different mixtures of engineered, bio-based earth mortars composed of bamboo particles, earth, and different cementitious materials. Four mixtures were assessed: mortars without bamboo particles (matrix), and mortars containing 3%, 6%, or 9% of bamboo particles by volume. The bulk density and thermal conductivity values obtained for the matrix and mortars with the highest percentage of bamboo particles (9%) were 1704.13 and 1471.80 kg/m3, and 0.62 and 0.43 W/M·K, respectively. Based on experimental results, thermal-energy simulations were carried out using a social housing project as a case study. The simulations evaluated different climate conditions and applied life cycle GHG emissions assessment methodology. Compared with typical cement and lime plastering mortars, the proposed bio-based earth mortars presented a superior thermal-energy performance and lower GHG emissions, particularly the 9% bamboo particles mixture. GHG emissions reached a maximum decrease of 28%. The main scientific contribution of this research is the presentation of an engineered, bio-based earth mortar that can be manufactured using local raw materials available in most developing countries with significant housing demands. The method used, based on experimental research, thermal-energy analysis, and life cycle GHG emissions, may be used for evaluating other innovative materials. It was verified that even with thin plastering in buildings, it is possible to achieve energy efficiency gains and to reduce GHG emissions.
Integrating Ecosystem Service Values and Economic Benefits for Sustainable Land Use Management in Semi-Arid Regions in Northern China
Authors: Jiang Honglei , Xu Xia , Wang Lingfei , Zhang Tong
Published: September 2021

Studies on land use structural optimization can support the sustainability of land resources. The Taipusi Banner lies in the arid and semiarid area of northern China, with rapid economic development and a vulnerable ecological condition. Taking the Taipusi Banner as a research case, we adopted a land use map and statistical data, and employed the ecosystem process model to establish five scenarios, including an economically optimal scenario, an ecologically optimal scenario, a comprehensively optimal scenario, a status quo, and a projected scenario. Based on multi-objective linear programming, the land use demand was optimized; then, the CLUE-S model and adaptability evaluation were adopted to establish spatial patterns. The ecological and economic benefits were then analyzed and policy suggestions are provided. The main results include the following: (1) The optimization outputs of various scenarios show that under optimization, cropland and forestland increased by 9.13% and 18.9%, respectively, and grassland decreased by 9.81%. (2) The land use optimization shows that comprehensive optimization aimed at achieving comprehensive benefits, ecological benefits, and economic benefits increased these benefits by 3.89%, 2.1%, and 6.2%, respectively. Compared with other scenarios, focusing on the comprehensive benefits of land use can result in the greatest increase in benefits to improve sustainability land resources. Land use optimization must consider not only the optimization of both the quantity and configuration but also the dimensions of both ecology and the economy. Land use should be based on a land suitability evaluation and optimization of the land use spatial configuration to update ineffective land uses and should gradually adjust both the ecological and engineering measures.
Current and Future Professional Insights on Cooperation towards Circular Economy Adoption
Authors: Palafox-Alcantar P. Giovani , Hunt Dexter V. L. , Rogers Christopher D. F.
Published: September 2021

A circular economy aims to capture the remaining value in waste through several disruptive actions such as reuse, recycle, recover, and regenerate. However, stakeholders in this transition often find themselves in conflict due to their different objectives and priorities. Cooperation is regarded as a critical feature in the implementation of a circular economy; however, it is not easily achieved in practice. Additionally, there is limited research regarding stakeholder cooperation in circular economy development. This paper aims to address this gap by analysing the characteristics of stakeholder cooperation through questionnaire surveys of two stakeholder groups with an interest in the adoption of circular economy principles for municipal solid waste management in Birmingham, UK: 101 MSc students focussing on urban sustainability and 27 businesses engaged in alternative sustainable materials. The paper’s primary contribution, being the first to survey participants about perceptions of other stakeholders, has been to gain insights into how stakeholder cooperation is key to facilitating the transition to a circular economy approach. The analysis demonstrated that circular economy awareness, cooperation, and readiness from stakeholders were high, yet their practices do not sufficiently align with this necessary foundation. That said, the study also revealed several encouraging perspectives from stakeholders toward circular economy development, despite benefits and costs not always being evident to all participants.
Social Media and Students’ Wellbeing: An Empirical Analysis during the Covid-19 Pandemic
Authors: Tkáčová Hedviga , Pavlíková Martina , Jenisová Zita , Maturkanič Patrik , Králik Roman
Published: September 2021

Various forms of social media (SM) appear to be very popular among young people because they provide information and entertainment, including a wide range of web technologies such as blogs, wikis, online social networks, and virtual networks. SM plays a huge role in the lives of children and teenagers, especially during the COVID-19 pandemic, when the computer becomes not only a means of entertainment or leisure, but also a necessary and everyday means of education and communication with other people. Thus, COVID-19 has brought a radical change, not only in the daily schedule and leisure time of pupils and students, but also in the perception of the procedures used by this specific group in the online space. Through our own research, using structured interviews and a questionnaire, we examine the use of SM as a tool to promote sustainable well-being in a group of high school students from various schools in central Slovak Republic (formerly Czechoslovakia). The research confirms that during the pandemic, the use of SM by the young respondents contributes significantly to well-being. This is the case when SM is used by high school students as a tool in promoting: (1) personal interests; (2) motivation; (3) communication and interpersonal connectivity; (4) preferred forms of online education; and (5) online games. The article presents a set of recommendations regarding the use of SM as a tool for sustaining the well-being of young people during the pandemic.
Risk-Based Due Diligence, Climate Change, Human Rights and the Just Transition
Authors: Bright Claire , Buhmann Karin
Published: September 2021

Climate change has been described as one of the greatest threats to people and the planet. Its impacts affect virtually the entire spectrum of internationally recognised human rights as well as the environment in and of itself. In relation to human rights, there is a growing consensus that companies should exercise human rights due diligence in order to identify and prevent their actual and potential adverse impacts. However, the relevance and implications of the concept of the due diligence have not yet fully been analysed in relation to climate change. In this paper, we explore the concept of risk-based due diligence, which builds on the concept of human rights due diligence but extends it to other areas such as the environment. Through a review of recent regulatory developments as well as case-law and other grievances, we analyse the three facets of risk-based due diligence for climate change—prevention, mitigation and remediation. We consider both the short term as well as the longer-term human rights and environmental implications of companies’ climate-related impacts, as well as those resulting from the company’s contributions to the green transition. We argue that risk-based due diligence offers an under-explored but important dual function: providing the operational means through which companies can identify and address the climate-related human rights and environmental impacts with which they may be involved, whilst also taking into consideration the human rights implications of their climate mitigation strategies and contributions to the just transition.
Used Tires as Fuel in Clinker Production: Economic and Environmental Implications
Authors: Castañón Ana María , Sanmiquel Lluís , Bascompta Marc , Vega y de la Fuente Antonio , Contreras Víctor , Gómez-Fernández Fernando
Published: September 2021

This work analyzes how gases emitted during the manufacture of clinker vary in a cement plant using two types of fuel: petroleum coke and unusable tires (UTs). This study is based on a case study using real time data on more than 40 process variables. Gases are analyzed from two points of the production process: from the sintering kiln, where the main focus of emissions to the atmosphere is by chimney, and from the preheater. The variation of CO and NOx depending on the oxygen and fuel type is studied. The SO2 levels are also analyzed and a decrease was observed when using the UTs. The quality of the clinker is compared according to the fuel type. The results are analyzed, on the one hand, by the quality of the clinker, determined by the content of the majority (C3S, alite) and minority (free CaO) phases, and, on the other hand, by the kiln sintering temperature, the most influential parameter in the productive process. It is verified that the clinker quality is maintained regardless of the type of fuel used. Therefore, the use of UTs as fuel could generate important economic and environmental benefits for cement companies.
The Optimization of Canola Crop Production through Wheat Residue Management within a Western Canadian Context—A Case Study of Saint-Front, Saskatchewan
Authors: Xin Xiaying , Huang Guohe , Halstead David , Gaetz Katelyn , Benmerrouche Leila , Huang Jing , Wu Yuwei , Zhang Jinbo , Fu Yupeng , Wang Nan
Published: September 2021

In this study, the processes of wheat residue degradation in combination with various tillage treatments were explored to determine the ideal management prescription for maximizing canola crop production. A field experiment within a western Canadian context (near Saint-Front, Saskatchewan), consisting of a 2 × 3 factorial design, was conducted to determine the fate of crop residue under different harvest and treatment scenarios. ATR-Fourier transform infrared (FTIR) spectroscopy, FTIR spectromicroscopy, and synchrotron-based X-ray fluorescence imaging (SR-XFI) were used to explore wheat residue degradation mechanisms. The results indicated maximum canola yields and residue degradation occurred in combination with a combine outfitted with an aftermarket chopper and post-harvest treatment by harrow. Crop residue degradation was attributed to cellulose/linen hydrolysis and supramolecular structure changes from high crystalline to amorphous cellulose. Multi-element loss usually accompanied crop residue degradation. An important aspect of this study is the adoption of field-scale analysis to accurately portray real-world sustainable management techniques within a western Canadian context. The findings provided an optimal combination of crop residue treatment and tillage treatment to increase canola production, which had the potential ability to be applied in other countries. It is also an initial attempt to develop a technical composite of FTIR spectromicroscopy and SR-XFI for examining the mechanism of residue decomposition.
Determinant Factors for Adoption of Government as a Platform in South Korea: Mediating Effects on the Perception of Intelligent Information Technology
Authors: Seo Hyungjun , Myeong Seunghwan
Published: September 2021

This study aims to shed light on determinant factors for the introduction of Government as a Platform (GaaP) by public officers who can be platform providers or main stakeholders in GaaP. It focuses on public officers in 261 Korean public agencies. In order to verify the research model’s hypotheses, we take advantage of Structural Equation Modeling and the Technology Acceptance Model. As a first result, concerning the direct effect on GaaP, the quality of open data, the scope of the stakeholders, and attitudes to civic engagement have a positive relationship on the perceived usefulness of Intelligent Information Technology (IIT). Second, in terms of the effect of IIT on GaaP, the perceived usefulness of IIT mediates positively on the intention to adopt GaaP based on the quality of open data, the scope of the stakeholders, and attitudes towards civic engagement. Based on these results, policy implications can be described as follows. Besides managing internal open data, governments should actively mine new open data that can create added value for innovation. They need to create an easily cooperative environment with other stakeholders, especially non-public participants, and governments should encourage public officers to more actively accept and utilize IIT in their jobs.
Fabrication of Catalytic Converter with Different Materials and Comparison with Existing Materials in Addition to Analysis of Turbine Installed at the Exhaust of 4 Stroke SI Engine
Authors: Kalvin Roman , Taweekun Juntakan , Maliwan Kittinan , Ali Hafiz Muhammad
Published: September 2021

Harmful pollutants (CO, NO, and unburnt hydrocarbons) coming out from the exhaust manifold of an engine must be converted into harmless gases by using catalytic converter. This field has seen vast research for increasing the conversion efficiency of pollutants by using different cheap metals. Nowadays, catalysts used in catalytic converter are noble metals, and they are also critical in the sense that they are not abundant on Earth. Platinum, palladium and rhodium are very expensive; hence, low-cost cars are not installed with catalytic converter, especially in third world countries. This research has been carried out to assess the catalytic activity of catalysts made from the salt/metal precursors, cerium sulphate tetra hydrate, manganese sulphate mono hydrate and copper sulphate penta hydrate that are not expensive and also less affected by the poison. Test sample catalysts were prepared through a coprecipitation method having different molar concentrations, and then tested for the conversion efficiency by applying the catalysts on ceramic plates by using flue gas analyzer. On the basis of the results, final catalysts were prepared and applied on a monolithic ceramic plate and then tested with regard to the resulting conversion rate of pollutants as compared to already installed catalytic converter. Moreover, turbine was installed in the exhaust passage to generate the power that would be utilized to run the electrical accessories of the engine. SOLIDWORKS were used for 3D CAD modeling and the flow analysis of turbine with radial inlet-axial outlet. In addition, ANSYS was used for stress-strain analysis.
Revitalization of Food in Sweden—A Closer Look at the REKO Network
Authors: Gruvaeus Axel , Dahlin Johanna
Published: September 2021

Can parts of the future food system include bi-weekly opportunities to purchase uneven stocks of produce at semi-remote locations? Current development in the Swedish food system suggests so. In the last few years, the Swedish Alternative Food Network ‘REKO’ has grown at an explosive pace. This anthropological article describes and discusses the organizational structure and motivations of the network, as well as discusses it from a revitalization perspective. From a netnographical and policy analysis perspective it is shown how the network uses social media and policy to convey a low bureaucracy, end to end, commercial space for local food—understood as a more “simple” way to achieve direct relationships in the food supply chain and thus create opportunities for local food networks. By adopting a view of the conventions and values of this Alternative Food Network as representing a parallel system aiming at facilitating direct relationships between ends in the food supply chain, the REKO initiative can be understood as a feasible model for a more satisfactory culture without needing to replace the mainstream food supply. The findings of the research deepen the understanding of REKO in Sweden by pointing towards how it can be understood as a sign of change of consumer preference and of prioritization of official policy concerns. The article also points towards how grass root movements can replicate success rapidly using policy documents capturing experiences and best practices spread online through social media.
Comprehensive Evaluation of the Provincial Sustainable Tourismization Level in China and Its Temporal and Spatial Differences
Authors: He Yuwei , Zhang Hui
Published: September 2021

Sustainable tourismization is a favorable development mode and pathway for the promotion of the coordinated development of the economy, society, and ecology. Based on the connotations of tourismization, a comprehensive evaluation index system of sustainable tourismization was constructed. This system consists of three dimensions: consumption tourismization, spatial tourismization, and industrial tourismization. The level, spatial, and temporal distribution characteristics, and differences in sustainable tourismization among China’s provinces from 2009 to 2018 were measured and analyzed using the improved entropy method, the Theil index, a spatial autocorrelation analysis, and other methods. It was found that the level of provincial sustainable tourismization in China has steadily increased over time, with the eastern region taking the lead. The overall differences and inter-regional differences in terms of the provincial sustainable tourismization level have generally decreased year-by-year. The intraregional differences within the eastern region were found to be the largest, and the rate of contribution of inter-regional differences to overall differences was shown to decrease gradually, while the rate of contribution of intraregional differences within the western region increased gradually. A positive spatial correlation in the provincial sustainable tourismization level was identified, and the spatial agglomeration effect showed an increasing trend. The spatial dependence was mainly characterized by “high–high” (HH) agglomeration, showing a ladder difference of “higher in the east and lower in the west”. The results of this study were used to identify where emphasis should be placed in terms of policy and strategy.
Blockchain during COVID-19: The Technology to Help Society
Authors: Capece Guendalina , Passiatore Domitilla
Published: September 2021

At the end of 2019, a new coronavirus was reported in the form of unknown pneumonia: It was the beginning of the SARS-CoV-2 pandemic. It is crucial to develop the strategies to manage this new pandemic in order to improve their effectiveness, as opposed to the ones adopted in 2003 during the SARS pandemic. In 17 years, new digital technologies and tools have been created; therefore, we can take advantage of them in the social management of the pandemic. The aim of our paper is to evaluate how blockchain technology can be used and what advantages it brings in managing an emergency situation such as of the COVID-19 pandemic. In particular, the effects of the adoption of this technology will be assessed when applied both to the management of the information flow between health infrastructures, and to track monetary, technical, and medical supply donations to hospital structures. We therefore propose a high-level, decentralized architecture that assists in administrating large-scale information and stores the gathered data in a blockchain supervised by the authorities. The distrust suffered by institutions today, the fear experienced in the last year due to the pandemic, and the birth of a technology that allows for the creation of reliable networks, pose thoughtful challenges to be faced to recover trust and hope for the future again.
Impact of Green Stormwater Infrastructure Age and Type on Water Quality
Authors: Poor Cara , Membrere Troy , Miyasato Jared
Published: September 2021

Green stormwater infrastructure (GSI) has become increasingly common to mitigate urban stormwater runoff. However, there is limited research on the impact of age and type of GSI. This study evaluated nutrient and metals concentrations in the soil water of five different GSI systems located at the University of Portland in Portland, Oregon. The GSI systems included a bioretention curb extension (part of Portland’s Green Street project), a bioretention basin, a bioretention planter, an infiltration basin, and a bioswale ranging in age from 2 to 11 years. Samples were taken from each system during rain events over a 10-month period and analyzed for copper (Cu), zinc (Zn), phosphate (PO43−), and total phosphorus (TP). Copper and zinc concentrations were found to be impacted by GSI age, with lower concentrations in older systems. The same trend was not found with PO43− and TP, where almost all GSI systems had soil water concentrations much higher than average stormwater concentrations. Age likely played a role in phosphorus soil water concentrations, but other factors such as sources had a stronger influence. Phosphorus is likely coming from the compost in the soil mix in addition to other sources in runoff. This study shows that GSI systems can be effective for copper and zinc, but changes to the soil mix design are needed to reduce high levels of PO43− and TP in soil water.
Energy Densification of Biomass-Derived Furfurals to Furanic Biofuels by Catalytic Hydrogenation and Hydrodeoxygenation Reactions
Authors: Vinod Nivedha , Dutta Saikat
Published: September 2021

The concomitant hydrolysis and dehydration of biomass-derived cellulose and hemicellulose to furfural (FUR) and 5-(hydroxymethyl)furfural (HMF) under acid catalysis allows a dramatic reduction in the oxygen content of the parent sugar molecules with a 100% carbon economy. However, most applications of FUR or HMF necessitate synthetic modifications. Catalytic hydrogenation and hydrogenolysis have been recognized as efficient strategies for the selective deoxygenation and energy densification of biomass-derived furfurals generating water as the sole byproduct. Efficient and eco-friendly catalysts have been developed for the selective hydrogenation of furfurals affording renewable furanic compounds such as 2-methylfuran, 2,5-dimethylfuran and 2-methyltetrahydrofuran with potential applications as biofuel, solvent and chemical feedstock. Hydrogen gas or hydrogen donor molecules, required for the above processes, can also be renewably obtained from biomass using catalytic processes, enabling a circular economy. In this review, the recent developments in the energy densification of furfurals to furanic compounds of commercial significance are elaborated, emphasizing the role of catalyst and the reaction parameters employed. Critical discussion on sourcing hydrogen gas required for the processes, using hydrogen donor solvents, catalyst design and the potential markets of furanic intermediates have been made. Critical evaluations of the accomplishments and challenges in this field are also provided.
Total Collisions in the N-Body Shape Space
Authors: Mercati Flavio , Reichert Paula
Published: September 2021

We discuss the total collision singularities of the gravitational N-body problem on shape space. Shape space is the relational configuration space of the system obtained by quotienting ordinary configuration space with respect to the similarity group of total translations, rotations, and scalings. For the zero-energy gravitating N-body system, the dynamics on shape space can be constructed explicitly and the points of total collision, which are the points of central configuration and zero shape momenta, can be analyzed in detail. It turns out that, even on shape space where scale is not part of the description, the equations of motion diverge at (and only at) the points of total collision. We construct and study the stratified total-collision manifold and show that, at the points of total collision on shape space, the singularity is essential. There is, thus, no way to evolve solutions through these points. This mirrors closely the big bang singularity of general relativity, where the homogeneous-but-not-isotropic cosmological model of Bianchi IX shows an essential singularity at the big bang. A simple modification of the general-relativistic model (the addition of a stiff matter field) changes the system into one whose shape-dynamical description allows for a deterministic evolution through the singularity. We suspect that, similarly, some modification of the dynamics would be required in order to regularize the total collision singularity of the N-body model.
A Fault Diagnosis and Prognosis Method for Lithium-Ion Batteries Based on a Nonlinear Autoregressive Exogenous Neural Network and Boxplot
Authors: Qiu Yan , Sun Jing , Shang Yunlong , Wang Dongchang
Published: September 2021

The frequent occurrence of electric vehicle fire accidents reveals the safety hazards of batteries. When a battery fails, its symmetry is broken, which results in a rapid degradation of its safety performance and poses a great threat to electric vehicles. Therefore, accurate battery fault diagnoses and prognoses are the key to ensuring the safe and durable operation of electric vehicles. Thus, in this paper, we propose a new fault diagnosis and prognosis method for lithium-ion batteries based on a nonlinear autoregressive exogenous (NARX) neural network and boxplot for the first time. Firstly, experiments are conducted under different temperature conditions to guarantee the diversity of the data of lithium-ion batteries and then to ensure the accuracy of the fault diagnosis and prognosis at different working temperatures. Based on the collected voltage and current data, the NARX neural network is then used to accurately predict the future battery voltage. A boxplot is then used for the battery fault diagnosis and early warning based on the predicted voltage. Finally, the experimental results (in a new dataset) and a comparative study with a back propagation (BP) neural network not only validate the high precision, all-climate applicability, strong robustness and superiority of the proposed NARX model but also verify the fault diagnosis and early warning ability of the boxplot. In summary, the proposed fault diagnosis and prognosis approach is promising in real electric vehicle applications.
A Real-Time Detection Method for Concrete Surface Cracks Based on Improved YOLOv4
Authors: Yao Gang , Sun Yujia , Wong Mingpu , Lv Xiaoning
Published: September 2021

Many structures in civil engineering are symmetrical. Crack detection is a critical task in the monitoring and inspection of civil engineering structures. This study implements a lightweight neural network based on the YOLOv4 algorithm to detect concrete surface cracks. In the extraction of backbone and the design of neck and head, the symmetry concept is adopted. The model modules are improved to reduce the depth and complexity of the overall network structure. Meanwhile, the separable convolution is used to realize spatial convolution, and the SPP and PANet modules are improved to reduce the model parameters. The convolutional layer and batch normalization layer are merged to improve the model inference speed. In addition, using the focal loss function for reference, the loss function of object detection network is improved to balance the proportion of the cracks and the background samples. To comprehensively evaluate the performance of the improved method, 10,000 images (256 × 256 pixels in size) of cracks on concrete surfaces are collected to build the database. The improved YOLOv4 model achieves an mAP of 94.09% with 8.04 M and 0.64 GMacs. The results show that the improved model is satisfactory in mAP, and the model size and calculation amount are greatly reduced. This performs better in terms of real-time detection on concrete surface cracks.
Quantum Fields as Category Algebras
Authors: Saigo Hayato
Published: September 2021

In the present paper, we propose a new approach to quantum fields in terms of category algebras and states on categories. We define quantum fields and their states as category algebras and states on causal categories with partial involution structures. By utilizing category algebras and states on categories instead of simply considering categories, we can directly integrate relativity as a category theoretic structure and quantumness as a noncommutative probabilistic structure. Conceptual relationships with conventional approaches to quantum fields, including Algebraic Quantum Field Theory (AQFT) and Topological Quantum Field Theory (TQFT), are also be discussed.
Longitudinal Changes in Running Gait Asymmetries and Their Relationship to Personal Record Race Times in Collegiate Cross Country Runners
Authors: Stiffler-Joachim Mikel R. , Kliethermes Stephanie A. , Martin Jack A. , Tanaka Claire S. , Benkert Ramsey , Heiderscheit Bryan C.
Published: September 2021

Minimizing between-limb asymmetries during running is often a goal of training, as increased asymmetries are related to decreased efficiency and increased energy expenditure. However, it is unknown if asymmetries change with increased running exposure or are related to actual race performance. The purpose of this study was to determine (1) if pre-season asymmetries changed year-to-year among collegiate cross country runners, and (2) if these asymmetries were associated with within-season personal records (PRs). Pre-season biomechanical test results and race performance data were analyzed for 54 unique runners (28 female) across six seasons, totaling 152 assessments (age: 19.1 (0.9) years, height: 1.71 (0.10) m, weight: 61.7 (7.7) kg (values = mean [standard deviation])). Biomechanical asymmetries included ground reaction forces; ground contact time; base of gait; foot inclination angle; and peak hip flexion, hip extension, hip adduction, pelvic drop, knee flexion, and ankle dorsiflexion. Year of collegiate eligibility was used to quantify training exposure. Asymmetries during running did not change across years of eligibility (p ≥ 0.12), except propulsive impulse, which decreased over time (p = 0.03). PR times were faster with decreased propulsive impulse asymmetry and increased AVLR and peak ankle dorsiflexion asymmetries. This is the first study to assess longitudinal asymmetries over time and provide potential targets for interventions aimed at modifying asymmetries to improve performance.
Modeling Extreme Values Utilizing an Asymmetric Probability Function
Authors: Almazah Mohammed M. A. , Almuqrin Muqrin A. , Eliwa Mohamed. S. , El-Morshedy Mahmoud , Yousof Haitham M.
Published: September 2021

In this article, a new flexible probability density function with three parameters is proposed for modeling asymmetric data (positive and negative) with different types of kurtosis (mesokurtic, leptokurtic and platykurtic). Some of its statistical and reliability properties, including hazard rate function, moments, moment generating function, incomplete moments, mean deviations, moment of the residual life, moment of the reversed residual life, and order statistics are derived. Its hazard rate function can be either constant, increasing-constant, decreasing-constant, U shape, upside down shape or upside down-U shape. Seven classical estimation methods are considered to estimate the unknown model parameters. Monte Carlo simulation experiments are performed to compare the performance of the seven different estimation methods. Finally, a distinctive asymmetric real data application is analyzed for illustrating the flexibility of the new model.
Integrability and Limit Cycles via First Integrals
Authors: Llibre Jaume
Published: September 2021

In many problems appearing in applied mathematics in the nonlinear ordinary differential systems, as in physics, chemist, economics, etc., if we have a differential system on a manifold of dimension, two of them having a first integral, then its phase portrait is completely determined. While the existence of first integrals for differential systems on manifolds of a dimension higher than two allows to reduce the dimension of the space in as many dimensions as independent first integrals we have. Hence, to know first integrals is important, but the following question appears: Given a differential system, how to know if it has a first integral? The symmetries of many differential systems force the existence of first integrals. This paper has two main objectives. First, we study how to compute first integrals for polynomial differential systems using the so-called Darboux theory of integrability. Furthermore, second, we show how to use the existence of first integrals for finding limit cycles in piecewise differential systems.
A Variety of Dynamic Steffensen-Type Inequalities on a General Time Scale
Authors: El-Deeb Ahmed Abdel-Moneim , Bazighifan Omar , Awrejcewicz Jan
Published: September 2021

This work is motivated by the work of Josip Pečarić in 2013 and 1982 and the work of Srivastava in 2017. By the utilization of the diamond-α dynamic inequalities, which are defined as a linear mixture of the delta and nabla integrals, we present and prove very important generalized results of diamond-α Steffensen-type inequalities on a general time scale. Symmetry plays an essential role in determining the correct methods to solve dynamic inequalities.
Stochastic Intermittency Fields in a von Kármán Experiment
Authors: Schmiegel Jürgen , Pons Flavio
Published: September 2021

We discuss the application of stochastic intermittency fields to describe and analyse the statistical properties of time series of the generalised turbulence intensity in an anisotropic and inhomogeneous turbulent flow and provide a parsimonious description of the one-, two-, and three-point statistics. In particular, we show that the three-point correlations can be predicted from observed two-point statistics. Our analysis is motivated by observed stylised features of the energy dissipation in homogeneous and isotropic situations where these statistical properties are well represented within the framework of stochastic intermittency fields. We find a close resemblance and conclude that stochastic intermittency fields may be relevant in more general situations.
Molecular Characterization of Spirometra decipiens Complex (Eucestoda: Diphyllobothriidea) from Uruguay
Authors: Armúa-Fernández María Teresa , Burutarán Mauricio , Bazzano Valentin , Félix María Laura , Castro Oscar , Venzal José Manuel
Published: September 2021

This study used a partial sequence of the mitochondrial cox1 gene for the reconstruction of the interrelationship of the adult and larval stages of Spirometra obtained from Cerdocyon thous, Leopardus munoai, Canis familiaris, Didelphis albiventris and Philodryas patagoniensis in Uruguay. The phylogenetic analysis showed that they were grouped with Spirometra decipiens from the Americas with a high bootstrap support. According to recent studies, American Spirometra species split into two S. decipiens complexes. Our findings strongly suggest that S. decipiens complex 1 is widely distributed in South America, and that wild and domestic canids are definitive hosts. Most of the samples (n = 10) grouped adults and plerocercoids that were retrieved from mammals and reptiles and seem to be the same taxon found in a Lycalopex gymnocercus from Argentina. A second clade was formed with Spirometra sp. found in a L. munoai as well as other wild felids such as a Puma concolor and a Leopardus pardalis (both from Argentina). On the other hand, S. decipiens complex 2 is present in South America and North America. South American clade parasitizes wild (and possibly domestic) felids and reptiles as definitive and intermediate hosts, respectively, whereas the North American clade found in snakes and captive meerkats (acting either as second intermediate or paratenic hosts) has unconfirmed definitive hosts.
Microplastics in the Environment: Intake through the Food Web, Human Exposure and Toxicological Effects
Authors: Pironti Concetta , Ricciardi Maria , Motta Oriana , Miele Ylenia , Proto Antonio , Montano Luigi
Published: September 2021

Recently, studies on microplastics (MPs) have increased rapidly due to the growing awareness of the potential health risks related to their occurrence. The first part of this review is devoted to MP occurrence, distribution, and quantification. MPs can be transferred from the environment to humans mainly through inhalation, secondly from ingestion, and, to a lesser extent, through dermal contact. As regards food web contamination, we discuss the microplastic presence not only in the most investigated sources, such as seafood, drinking water, and salts, but also in other foods such as honey, sugar, milk, fruit, and meat (chickens, cows, and pigs). All literature data suggest not-negligible human exposure to MPs through the above-mentioned routes. Consequently, several research efforts have been devoted to assessing potential human health risks. Initially, toxicological studies were conducted with aquatic organisms and then with experimental mammal animal models and human cell cultures. In the latter case, toxicological effects were observed at high concentrations of MPs (polystyrene is the most common MP benchmark) for a short time. Further studies must be performed to assess the real consequences of MP contamination at low concentrations and prolonged exposure.
Removal of Aflatoxin B1 by Edible Mushroom-Forming Fungi and Its Mechanism
Authors: Choo Min-Jung , Hong Sung-Yong , Chung Soo-Hyun , Om Ae-Son
Published: September 2021

Aflatoxins (AFs) are biologically active toxic metabolites, which are produced by certain toxigenic Aspergillus sp. on agricultural crops. In this study, five edible mushroom-forming fungi were analyzed using high-performance liquid chromatography fluorescence detector (HPLC-FLD) for their ability to remove aflatoxin B1 (AFB1), one of the most potent naturally occurring carcinogens known. Bjerkandera adusta and Auricularia auricular-judae showed the most significant AFB1 removal activities (96.3% and 100%, respectively) among five strains after 14-day incubation. The cell lysate from B. adusta exhibited higher AFB1 removal activity (35%) than the cell-free supernatant (13%) after 1-day incubation and the highest removal activity (80%) after 5-day incubation at 40 °C. In addition, AFB1 analyses using whole cells, cell lysates, and cell debris from B. adusta showed that cell debris had the highest AFB1 removal activity at 5th day (95%). Moreover, exopolysaccharides from B. adusta showed an increasing trend (24–48%) similar to whole cells and cell lysates after 5- day incubation. Our results strongly suggest that AFB1 removal activity by whole cells was mainly due to AFB1 binding onto cell debris during early incubation and partly due to binding onto cell lysates along with exopolysaccharides after saturation of AFB1 binding process onto cell wall components.
Analog Particle Production Model for General Classes of Taub-NUT Black Holes
Authors: Foo Joshua , Good Michael R. R. , Mann Robert B.
Published: September 2021

We derive a correspondence between the Hawking radiation spectra emitted from general classes of Taub-NUT black holes with that induced by the relativistic motion of an accelerated Dirichlet boundary condition (i.e., a perfectly reflecting mirror) in (1+1)-dimensional flat spacetime. We demonstrate that the particle and energy spectra is thermal at late times and that particle production is suppressed by the NUT parameter. We also compute the radiation spectrum in the rotating, electrically charged (Kerr–Newman) Taub-NUT scenario, and the extremal case, showing, explicitly, how these parameters affect the outgoing particle and energy fluxes.
Characterization of a Novel Phage ΦAb1656-2 and Its Endolysin with Higher Antimicrobial Activity against Multidrug-Resistant Acinetobacter baumannii
Authors: Kim Kyeongmin , Islam Md Maidul , Kim Dooyoung , Yun Sung Ho , Kim Jungmin , Lee Je Chul , Shin Minsang
Published: September 2021

Acinetobacter baumannii is a nosocomial pathogen, which is a problem worldwide due to the emergence of a difficult-to-treat multidrug-resistant A. baumannii (MDRAB). Endolysins are hydrolytic enzymes produced by a bacteriophage that can be used as a potential therapeutic agent for multidrug-resistant bacterial infection in replacing antibiotics. Here, we isolated a novel bacteriophage through prophage induction using mitomycin C from clinical A. baumannii 1656-2. Morphologically, ΦAb1656-2 was identified as a Siphoviridae family bacteriophage, which can infect MDRAB. The whole genome of ΦAb1656-2 was sequenced, and it showed that it is 50.9 kb with a G + C content of 38.6% and 68 putative open reading frames (ORFs). A novel endolysin named AbEndolysin with an N-acetylmuramidase-containing catalytic domain was identified, expressed, and purified from ΦAb1656-2. Recombinant AbEndolysin showed significant antibacterial activity against MDRAB clinical strains without any outer membrane permeabilizer. These results suggest that AbEndolysin could represent a potential antimicrobial agent for treating MDRAB clinical isolates.
Does the Zinc Finger Antiviral Protein (ZAP) Shape the Evolution of Herpesvirus Genomes?
Authors: Lin Yao-Tang , Chau Long-Fung , Coutts Hannah , Mahmoudi Matin , Drampa Vayalena , Lee Chen-Hsuin , Brown Alex , Hughes David J. , Grey Finn
Published: September 2021

An evolutionary arms race occurs between viruses and hosts. Hosts have developed an array of antiviral mechanisms aimed at inhibiting replication and spread of viruses, reducing their fitness, and ultimately minimising pathogenic effects. In turn, viruses have evolved sophisticated counter-measures that mediate evasion of host defence mechanisms. A key aspect of host defences is the ability to differentiate between self and non-self. Previous studies have demonstrated significant suppression of CpG and UpA dinucleotide frequencies in the coding regions of RNA and small DNA viruses. Artificially increasing these dinucleotide frequencies results in a substantial attenuation of virus replication, suggesting dinucleotide bias could facilitate recognition of non-self RNA. The interferon-inducible gene, zinc finger antiviral protein (ZAP) is the host factor responsible for sensing CpG dinucleotides in viral RNA and restricting RNA viruses through direct binding and degradation of the target RNA. Herpesviruses are large DNA viruses that comprise three subfamilies, alpha, beta and gamma, which display divergent CpG dinucleotide patterns within their genomes. ZAP has recently been shown to act as a host restriction factor against human cytomegalovirus (HCMV), a beta-herpesvirus, which in turn evades ZAP detection by suppressing CpG levels in the major immediate-early transcript IE1, one of the first genes expressed by the virus. While suppression of CpG dinucleotides allows evasion of ZAP targeting, synonymous changes in nucleotide composition that cause genome biases, such as low GC content, can cause inefficient gene expression, especially in unspliced transcripts. To maintain compact genomes, the majority of herpesvirus transcripts are unspliced. Here we discuss how the conflicting pressures of ZAP evasion, the need to maintain compact genomes through the use of unspliced transcripts and maintaining efficient gene expression may have shaped the evolution of herpesvirus genomes, leading to characteristic CpG dinucleotide patterns.