bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep Residual Involution Network for Hyperspectral Image Classification
Authors: Meng Zhe , Zhao Feng , Liang Miaomiao , Xie Wen
Published: August 2021

Convolutional neural networks (CNNs) have achieved great results in hyperspectral image (HSI) classification in recent years. However, convolution kernels are reused among different spatial locations, known as spatial-agnostic or weight-sharing kernels. Furthermore, the preference of spatial compactness in convolution (typically, 3×3 kernel size) constrains the receptive field and the ability to capture long-range spatial interactions. To mitigate the above two issues, in this article, we combine a novel operation called involution with residual learning and develop a new deep residual involution network (DRIN) for HSI classification. The proposed DRIN could model long-range spatial interactions well by adopting enlarged involution kernels and realize feature learning in a fairly lightweight manner. Moreover, the vast and dynamic involution kernels are distinct over different spatial positions, which could prioritize the informative visual patterns in the spatial domain according to the spectral information of the target pixel. The proposed DRIN achieves better classification results when compared with both traditional machine learning-based and convolution-based methods on four HSI datasets. Especially in comparison with the convolutional baseline model, i.e., deep residual network (DRN), our involution-powered DRIN model increases the overall classification accuracy by 0.5%, 1.3%, 0.4%, and 2.3% on the University of Pavia, the University of Houston, the Salinas Valley, and the recently released HyRANK HSI benchmark datasets, respectively, demonstrating the potential of involution for HSI classification.
PAG-YOLO: A Portable Attention-Guided YOLO Network for Small Ship Detection
Authors: Hu Jianming , Zhi Xiyang , Shi Tianjun , Zhang Wei , Cui Yang , Zhao Shenggang
Published: August 2021

The YOLO network has been extensively employed in the field of ship detection in optical images. However, the YOLO model rarely considers the global and local relationships in the input image, which limits the final target prediction performance to a certain extent, especially for small ship targets. To address this problem, we propose a novel small ship detection method, which improves the detection accuracy compared with the YOLO-based network architecture and does not increase the amount of computation significantly. Specifically, attention mechanisms in spatial and channel dimensions are proposed to adaptively assign the importance of features in different scales. Moreover, in order to improve the training efficiency and detection accuracy, a new loss function is employed to constrain the detection step, which enables the detector to learn the shape of the ship target more efficiently. The experimental results on a public and high-quality ship dataset indicate that our method realizes state-of-the-art performance in comparison with several widely used advanced approaches.
Combined Block Adjustment for Optical Satellite Stereo Imagery Assisted by Spaceborne SAR and Laser Altimetry Data
Authors: Zhang Guo , Jiang Boyang , Wang Taoyang , Ye Yuanxin , Li Xin
Published: August 2021

To ensure the accuracy of large-scale optical stereo image bundle block adjustment, it is necessary to provide well-distributed ground control points (GCPs) with high accuracy. However, it is difficult to acquire control points through field measurements outside the country. Considering the high planimetric accuracy of spaceborne synthetic aperture radar (SAR) images and the high elevation accuracy of satellite-based laser altimetry data, this paper proposes an adjustment method that combines both as control sources, which can be independent from GCPs. Firstly, the SAR digital orthophoto map (DOM)-based planar control points (PCPs) acquisition is realized by multimodal matching, then the laser altimetry data are filtered to obtain laser altimetry points (LAPs), and finally the optical stereo images’ combined adjustment is conducted. The experimental results of Ziyuan-3 (ZY-3) images prove that this method can achieve an accuracy of 7 m in plane and 3 m in elevation after adjustment without relying on GCPs, which lays the technical foundation for a global-scale satellite image process.
Projection of Air Pollution in Northern China in the Two RCPs Scenarios
Authors: Dou Chengrong , Ji Zhenming , Xiao Yukun , Hu Zhiyuan , Zhu Xian , Dong Wenjie
Published: August 2021

Air pollution in North China (NC) is an important issue affecting the economy and health. In this study, we used a regional climate model, the Weather Research and Forecasting Model with Chemistry (WRF-Chem) to project air pollution in NC and investigate the variations of air pollutions response to future climate changes, which probably has an implication to strategy and control policy for air quality in NC. A comprehensive model evaluation was conducted to verify the simulated aerosol optical depth (AOD) based on MODIS and MISR datasets, and the model also showed reasonable results in aerosol concentrations. Future changes of air pollution in the middle of the 21st century (2031–2050) were projected in the two Representative Concentration Pathways (RCP4.5 and RCP8.5) and compared with the situation in the historical period (1986–2005). In the two RCPs, the simulated averaged PM2.5 concentration was projected with the highest values of 50–250 μg·m−3 over the Bohai Rim Economic Circle (BREC) in winter. The maximum AOD is in the Beijing–Tianjin–Hebei (BTH) region in summer, with an average value of 0.68. In winter, in the RCP4.5 scenario, PM2.5 concentration and AOD obviously declined in BTH and Shandong province. However, in the RCP8.5 scenario, PM2.5 concentration and AOD increased. Results indicated that air pollution would be reduced in winter if society developed in the low emission pathway. Precipitation was projected to increase both in the two RCPs scenarios in spring, summer, and winter, but it was projected to decrease in autumn. The planetary boundary layer height decreased in the two RCPs scenarios in the central region of NC in the summer and winter. The results indicated that changes of meteorological conditions have great impact on air pollution in future scenarios.
Transformer Meets Convolution: A Bilateral Awareness Network for Semantic Segmentation of Very Fine Resolution Urban Scene Images
Authors: Wang Libo , Li Rui , Wang Dongzhi , Duan Chenxi , Wang Teng , Meng Xiaoliang
Published: August 2021

Semantic segmentation from very fine resolution (VFR) urban scene images plays a significant role in several application scenarios including autonomous driving, land cover classification, urban planning, etc. However, the tremendous details contained in the VFR image, especially the considerable variations in scale and appearance of objects, severely limit the potential of the existing deep learning approaches. Addressing such issues represents a promising research field in the remote sensing community, which paves the way for scene-level landscape pattern analysis and decision making. In this paper, we propose a Bilateral Awareness Network which contains a dependency path and a texture path to fully capture the long-range relationships and fine-grained details in VFR images. Specifically, the dependency path is conducted based on the ResT, a novel Transformer backbone with memory-efficient multi-head self-attention, while the texture path is built on the stacked convolution operation. In addition, using the linear attention mechanism, a feature aggregation module is designed to effectively fuse the dependency features and texture features. Extensive experiments conducted on the three large-scale urban scene image segmentation datasets, i.e., ISPRS Vaihingen dataset, ISPRS Potsdam dataset, and UAVid dataset, demonstrate the effectiveness of our BANet. Specifically, a 64.6% mIoU is achieved on the UAVid dataset.
The Effect of the Formation of Superelastic NiTi Phase on Static and Dynamic Corrosion Performance of Ni-P Coating
Authors: Li Zhi , Farhat Zoheir
Published: August 2021

The addition of superelastic NiTi particles is a great benefit to the toughness of the Ni-P coating. Nonetheless, NiTi nanopowder costs 10 times more than Ti nanopowder. Therefore, in the present study, to reduce the cost, Ni-P-NiTi composite coatings were prepared on AISI 1018 steel substrates by the electroless incorporation of Ti nanoparticles into Ni-P followed by the annealing of Ni-P-Ti coatings. The effect of the formation of a superelastic NiTi phase on static and dynamic corrosion performance was investigated. It was found that the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) has much higher static corrosion resistance than the as-deposited Ni-P coating. The dynamic corrosion rates in the absence of abrasive particles are 10 times higher than the static corrosion rates of the coatings. The dynamic corrosion rates in the presence of abrasive particles are one order of magnitude higher than the dynamic corrosion rates in the absence of abrasive particles. The formation of a superelastic NiTi phase considerably improved the static and dynamic corrosion performance of the Ni-P coating. In the absence of abrasive particles under flowing condition, the dynamic corrosion resistance of the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) is 19 times higher than that of the as-deposited Ni-P coating. In the most aggressive environment (in the presence of abrasive particles), the dynamic corrosion resistance of the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) is four times higher than that of the as-deposited Ni-P coating. The annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) can be used in applications where high corrosion resistance is required, especially in an extremely aggressive environment.
Applications of Biocatalysts for Sustainable Oxidation of Phenolic Pollutants: A Review
Authors: Salehi Sanaz , Abdollahi Kourosh , Panahi Reza , Rahmanian Nejat , Shakeri Mozaffar , Mokhtarani Babak
Published: August 2021

Phenol and its derivatives are hazardous, teratogenic and mutagenic, and have gained significant attention in recent years due to their high toxicity even at low concentrations. Phenolic compounds appear in petroleum refinery wastewater from several sources, such as the neutralized spent caustic waste streams, the tank water drain, the desalter effluent and the production unit. Therefore, effective treatments of such wastewaters are crucial. Conventional techniques used to treat these wastewaters pose several drawbacks, such as incomplete or low efficient removal of phenols. Recently, biocatalysts have attracted much attention for the sustainable and effective removal of toxic chemicals like phenols from wastewaters. The advantages of biocatalytic processes over the conventional treatment methods are their ability to operate over a wide range of operating conditions, low consumption of oxidants, simpler process control, and no delays or shock loading effects associated with the start-up/shutdown of the plant. Among different biocatalysts, oxidoreductases (i.e., tyrosinase, laccase and horseradish peroxidase) are known as green catalysts with massive potentialities to sustainably tackle phenolic contaminants of high concerns. Such enzymes mainly catalyze the o-hydroxylation of a broad spectrum of environmentally related contaminants into their corresponding o-diphenols. This review covers the latest advancement regarding the exploitation of these enzymes for sustainable oxidation of phenolic compounds in wastewater, and suggests a way forward.
Learning Remotely during a Pandemic: Are Students in a Developing Country Fully Equipped with Tools for Swift Changes?
Authors: Perera Eranda , Gamage Kelum A. A.
Published: August 2021

Many higher educational institutes are forced to the online mode of lecture delivery without fully understanding students’ perspectives of remote study during COVID-19, and the resource limitations of students to engage successfully in remote learning. The present study aimed to understand this gap and the students’ perspective. We collected and analysed the devices, which used by the students to connect to remote learning in a developing country. It was found that the majority of students are dependent on the laptop-smartphone combination to engage in remote learning, particularly the students in rural areas. The results highlighted the importance of smartphones in the online learning experience, considering their affordability, relatively long battery life, inbuilt internet capabilities, and portability. Although students indicated their willingness for remote learning, they clearly recognised the need for face-to-face teaching return to avoid some of the challenges and disadvantages they face as a part of remote learning.
China’s Special Poor Areas and Their Geographical Conditions
Authors: Xu Xin , Wang Chengjin , Ma Shiping , Zhang Wenzhong
Published: August 2021

Special functional areas and poor areas tend to spatially overlap, and poverty is a common feature of both. Special poor areas, taken as a kind of “policy space,” have attracted the interest of researchers and policymakers around the world. This study proposes a basic concept of special poor areas and uses this concept to develop a method to identify them. Poor counties in China are taken as the basic research unit and overlaps in spatial attributes including old revolutionary bases, borders, ecological degradation, and ethnic minorities, are used to identify special poor areas. The authors then analyze their basic quantitative structure and pattern of distribution to determine the geographical bases’ formation and development. The results show that 304 counties in China, covering a vast territory of 12 contiguous areas that contain a small population, are lagging behind the rest of the country. These areas are characterized by rich energy and resource endowments, important ecological functions, special historical status, and concentrated poverty. They are considered “special poor” for geographical reasons such as a relatively harsh natural geographical environment, remote location, deteriorating ecological environment, and an inadequate infrastructure network and public service system. Some areas suffer from underdevelopment and even lack the infrastructure for basic living. In order to prevent further deterioration of the economic, social, and ecological environments in these areas, targeted policies need to be implemented.
Coping with English for Academic Purposes Provision during COVID-19
Authors: Kohnke Lucas , Jarvis Andrew
Published: August 2021

COVID-19 and the shift to online teaching necessitated a change in approach for English for Academic Purposes (EAP) teachers in preparing their students for university studies. This study explored how EAP instructors coped with and adapted their provision for emergency remote teaching. The study was conducted at an English-medium university in Hong Kong and a qualitative case study approach was adopted. The results revealed two overarching themes of opportunity and challenge. While the sudden shift to online teaching forced innovation and fostered collaborative learning and feedback, teachers experienced difficulties in communicating with students and monitoring their learning. The study voices teacher perspectives in delivering EAP courses online and highlights important implications for the successful delivery of future online EAP provisions.
Experimental Analysis of Passive Strategies in Houses with Glass Façades for the Use of Natural Light
Authors: Aguilera-Benito Patricia , Piña-Ramírez Carolina , Varela-Lujan Sheila
Published: August 2021

The main objective of this research was to analyze the passive solutions that help to reduce energy consumption through the use of natural light in buildings. In this case, the analysis focused on the use of natural light in buildings with all façades made of glass. Buildings designed with the criterion of regenerative sustainability, such as glass buildings, consider not only energy efficiency and the use of renewable and/or alternative energies, but also the improvement of the health and well-being of users—very important factors during an era in which the time spent at home has been increased due to the COVID-19 pandemic (disease caused by the SARS-CoV-2 virus). This experimental research was based on the analysis of data collected during a full year of monitoring of two scale models of Farnsworth House, a house with glass façades in all of its orientations. The results allowed us to conclude that these passive elements must be taken into account in the initial design of a building; a solar control sheet is also advisable in this type of glass building because it greatly reduces the illuminance inside the spaces, and the use of overhangs distributes the illuminance inside the rooms more evenly. In addition, the use of scale models provides a more accurate view of the parameters related to light energy.
Transparency and Accountability in Sports: Measuring the Social and Financial Performance of Spanish Professional Football
Authors: Urdaneta Rudemarlyn , Guevara-Pérez Juan C. , Llena-Macarulla Fernando , Moneva José M.
Published: August 2021

This study reviews the impact of the Spanish Transparency Law (TL) 19/2013 and the Union of European Football Associations’ (UEFA) Financial Fair Play (FFP) regulations, on the transparency and accountability of Spanish professional football clubs, and examines the influence of financial performance on the transparency of Spanish football clubs. The study uses a Panel Data methodology (FGLS) to compare the international transparency index for football clubs (INFUT) with the criteria of UEFA’s FFP as a measure of the social and financial performance, respectively, on a sample of 28 Spanish professional teams of first and second division during the periods of 2015, 2016, and 2019. The study reveals that the implementation of TL 19/2013 and UEFA’s FFP has improved the transparency and accountability of clubs. On the one hand, the TL has facilitated access to financial information, and, on the other, the FFP regulations have contributed to improving the balance and financial viability of the clubs. The study also reveals that financial performance directly influences the transparency of clubs.
Social Interaction: A Crucial Means to Promote Sustainability in Initial Teacher Training
Authors: Carmona-Medeiro Enrique , Cardeñoso Domingo José María
Published: August 2021

This study aims to identify the set of elements in the educational process that affect the creation of a teaching profile consistent with the principles of sustainability. In this research, we focus on identifying those sustainability attributes related to understanding social interaction and its role in the learning process of logical-mathematical knowledge. Social interaction is an essential part of the principle of collaboration. The study participants were 133 future teachers, students of the degree in Early Childhood Education at the Universidad de Cádiz (Spain). Qualitative methods and techniques were used to collect data, and mixed methods and techniques were employed for their analysis. The data relating to the student’s perception of the importance of social interaction in learning were gathered through the final reports produced by the students. The data were processed by classifying them into categories and subcategories. The meaning condensation method used enabled identifying 33 sustainability attributes linked to socio-cultural learning. Those attributes identify and describe the internal dynamics of cooperative learning and show the synergies and interrelationships between social interactions, socio-cognitive conflict and language. The results stress the importance of a meaningful understanding of the role of social interaction in learning in order to promote the principles of sustainability.
Mapping National Environmental Sustainability Distribution by Ecological Footprint: The Case of Italy
Authors: Franco Silvio , Pancino Barbara , Martella Angelo
Published: August 2021

The paper proposes a possible way of spatially representing sustainability in Italy. For this purpose, the ecological footprint approach was used as a methodological framework to assess the level of sustainability of the 8092 Italian municipalities. For each municipality, the exploitation of ecosystem services, assessed by the ecological footprint indicator, and the corresponding availability of biological capacity, associated to an indicator, have been calculated and compared, thus generating a map representing the relative sustainability of Italian municipalities. The results show a very scattered distribution of ecological balance, wherein unsustainable conditions characterize more than 60% of the territory and almost 95% of the Italian population. Despite the limitations of the methodology and some assumptions regarding the ecological footprint assessment at the municipality level, the study represents an attempt to produce an innovating tool that, based on an operational definition of sustainability, can represent natural resource exploitation at the local level, and provide useful information to address coherent and targeted environmental policies of sustainability.
Quantitative Modeling of Human Responses to Changes in Water Resources Availability: A Review of Methods and Theories
Authors: Meijer Karen S. , Schasfoort Femke , Bennema Maike
Published: August 2021

In rural areas in developing countries where livelihoods directly depend on agriculture, shortage of water can have severe socio-economic and humanitarian consequences and has been suggested to result in conflict and migration. Understanding such responses is important for the development of effective water management policies and other interventions. However, despite the availability of extensive knowledge on water-related human behavior, water resources planning studies do not always look beyond direct impacts. Therefore, this paper assesses literature on water-related human responses, the quantification and conceptualization methods and theories used, the scale at which models are applied, and the extent to which findings are used to make policy recommendations. We found system dynamics approaches mostly applied for policy evaluations, but often with a limited integration of human behavior beyond water use; agent-based models seem to be suited for policy analysis, but only limitedly applied for that purpose; and statistical studies to present the widest range of human responses and explanatory factors, but without making the behavioral mechanisms explicit. In fact, only a limited number of studies was based on behavioral theories. Based on these findings we recommend eight steps to facilitate quantification of human responses for water resources planning purposes.
The Potential of Stormwater Management in Addressing the Urban Heat Island Effect: An Economic Valuation
Authors: Johnson Daniel , Exl Judith , Geisendorf Sylvie
Published: August 2021

Urban green infrastructure (UGI) within sustainable stormwater management provides numerous benefits to urban residents, including urban heat island (UHI) mitigation. Cost–benefit analyses (CBA) for UGI have been conducted at neighborhood level with a focus on stormwater management, but valuations of reductions in heat-related hospitalizations and mortality are lacking. These benefits create significant social value; the quantification thereof is essential for urban planning in providing a scientific foundation for the inclusion of UGI in UHI mitigation strategies. This study assesses the potential of three UGI scenarios developed for an urban neighborhood in Berlin, Germany. First, climate data analyses were conducted to determine the cooling effects of tree drains, facade greening, and green roofs. Second, a CBA was performed for each scenario to value UHI mitigation by estimating the damage costs avoided in reduced heat-related hospitalizations and fatalities, using the net present value (NPV) and benefit–cost ratio (BCR) as indicators of economic feasibility. The results indicate heat mitigation capabilities of all three UGI types, with tree drains achieving the strongest cooling effects. Regarding economic feasibility, all scenarios achieve positive NPVs and BCRs above one. The findings confirm the potential of stormwater management in mitigating UHI and generating substantial social value.
A Partial Least-Square Mediation Analysis of the Contribution of Cross-Campus Entrepreneurship Education to Students’ Entrepreneurial Intentions
Authors: Dodescu Anca-Otilia , Botezat Elena-Aurelia , Constăngioară Alexandru , Pop-Cohuţ Ioana-Crina
Published: August 2021

The present paper presents findings of entrepreneurial intentions of a group of 313 undergraduate students of the University of Oradea, Romania, from different non-economic fields of study (engineering, health, social sciences, mathematics, natural sciences, humanities, and arts), including students from rural areas and other disadvantaged groups enrolled in an entrepreneurship education project financed through European Social Fund. A complex mediation chain is set in place in a net of relationships linking the benefits of entrepreneurial education to entrepreneurship self-efficacy, entrepreneurship attitudes, perceived behavioral control, and subjective norms in our estimation of entrepreneurial intentions. Using a multigroup analysis, we address the OECD inclusive entrepreneurship perspective of students ‘at-risk’ on the labor market and under-represented in entrepreneurship, identifying how the benefits of entrepreneurship education can be better capitalized by each category. The present paper advocates the necessity to extend entrepreneurship education outside the economics and business specializations.
Residents’ Perception of Changing Local Conditions in the Context of Tourism Development: The Case of Phuket Island
Authors: Tuntipisitkul Pisit , Tsusaka Takuji W. , Kim Sohee Minsun , Shrestha Rajendra P. , Sasaki Nophea
Published: August 2021

Lack of understanding of the ways local subpopulations perceive various changes associated with rapid growth of the tourism industry may lead to unsustainable development. This study assessed the levels and determinants of residents’ perception regarding the changes in environmental, sociocultural, and economic conditions associated with tourism development in Phuket, Thailand. A structured questionnaire survey was conducted with 450 residents covering all three districts of Phuket Province to capture overall indicators and detailed sub-indicators of perception, whilst factors affecting the perceived changes were examined through ordered logistic regression and seemingly unrelated regression (SUR) analyses. The descriptive statistics showed that residents perceived unfavorable changes in various conditions in the island such as increased levels of pollution, road accidents, traffic congestion, and costs of living, while at the same time acknowledging the importance of long-term economic contribution of tourism development. Moreover, regression analyses revealed that various sociodemographic factors such as gender, education, residency duration, and occupation influenced residents’ perception of the changing local conditions. At the sub-indicator level, detailed insights were obtained such as female residents being more likely to positively perceive some of the changes such as increased availability of public space. Implications and suggestions for policy design and planning are discussed in detail.
Need for Seismic Hydrology Research with a Geomicrobiological Focus
Authors: Kim Heejung
Published: August 2021

Earthquakes cause deformation in previously stable groundwater environments, resulting in changes to the hydrogeological characteristics. The changes to hydrological processes following large-scale earthquakes have been investigated through many physicochemical studies, but understanding of the associated geomicrobiological responses remains limited. To complement the understanding of earthquakes gathered using hydrogeochemical approaches, studies on the effects of the Earth’s deep crustal fluids on microbial community structures can be applied. These studies could help establish the degree of resilience and sustainability of the underground ecosystem following an earthquake. Furthermore, investigations on changes in the microbial community structure of the Earth’s deep crustal fluids before and after an earthquake can be used to predict an earthquake. The results derived from studies that merge hydrogeochemical and geomicrobiological changes in the deep crustal fluids due to the effect of stress on rock characteristics within a fault zone can be used to correlate these factors with earthquake occurrences. In addition, an earthquake risk evaluation method may be developed based on the observable characteristics of fault-zone aquifers.
Significance of Agriculture for Bioeconomy in the Member States of the European Union
Authors: Nowak Anna , Kobiałka Anna , Krukowski Artur
Published: August 2021

Bioeconomy is a response of the European Union and its member states to global challenges such as ensuring food security, mandatory sustainable management of natural resources, mitigating climate change and reducing dependency on non-renewable resources. One of the sectors playing an important role in the development of bioeconomy is agriculture, which accounts for the largest part of biomass used as a raw material for producing bioproducts. This paper is an attempt to answer the following questions: What is the essence and significance of the bioeconomy sector in the EU? How significant is agriculture to the bioeconomy sector? What is the potential and competitiveness of agriculture in EU countries? Data used in surveys is sourced from the Data-Modelling platform of agro-economics research and covers the years 2008–2017. The position of agriculture in the bioeconomy was determined based on measures such as level of employment and gross value added (GVA), turnover, while its competitiveness was assessed based on labour productivity. The results of surveys showed that more than 50% of all bioeconomy workers were employed in agriculture. The sector produced nearly 30% GVA and had a more than 18% share in bioeconomy turnover. Member states of the European Union featured diverse agricultural potential. At the same time, the productivity of agriculture was one of the lowest in the bioeconomy sector. The importance of agriculture stems not only from its food function, but also from the production of biomass. However, its social function is equally important, and in the face of escalating environmental problems the function connected with reducing external costs and producing environmental public goods has become complementary.
Generating the Triangulations of the Torus with the Vertex-Labeled Complete 4-Partite Graph K2,2,2,2
Authors: Lawrencenko Serge , Magomedov Abdulkarim M.
Published: August 2021

Using the orbit decomposition, a new enumerative polynomial P(x) is introduced for abstract (simplicial) complexes of a given type, e.g., trees with a fixed number of vertices or triangulations of the torus with a fixed graph. The polynomial has the following three useful properties. (I) The value P(1) is equal to the total number of unlabeled complexes (of a given type). (II) The value of the derivative P′(1) is equal to the total number of nontrivial automorphisms when counted across all unlabeled complexes. (III) The integral of P(x) from 0 to 1 is equal to the total number of vertex-labeled complexes, divided by the order of the acting group. The enumerative polynomial P(x) is demonstrated for trees and then is applied to the triangulations of the torus with the vertex-labeled complete four-partite graph G=K2,2,2,2, in which specific case P(x)=x31. The graph G embeds in the torus as a triangulation, T(G). The automorphism group of G naturally acts on the set of triangulations of the torus with the vertex-labeled graph G. For the first time, by a combination of algebraic and symmetry techniques, all vertex-labeled triangulations of the torus (12 in number) with the graph G are classified intelligently without using computing technology, in a uniform and systematic way. It is helpful to notice that the graph G can be converted to the Cayley graph of the quaternion group Q8 with the three imaginary quaternions i, j, k as generators.
Fermat Metrics
Authors: Masiello Antonio
Published: August 2021

In this paper we present a survey of Fermat metrics and their applications to stationary spacetimes. A Fermat principle for light rays is stated in this class of spacetimes and we present a variational theory for the light rays and a description of the multiple image effect. Some results on variational methods, as Ljusternik-Schnirelmann and Morse Theory are recalled, to give a description of the variational methods used. Other applications of the Fermat metrics concern the global hyperbolicity and the geodesic connectedeness and a characterization of the Sagnac effect in a stationary spacetime. Finally some possible applications to other class of spacetimes are considered.
Regio- and Stereoselective Synthesis of a New Series of Spirooxindole Pyrrolidine Grafted Thiochromene Scaffolds as Potential Anticancer Agents
Authors: Barakat Assem , Islam Mohammad Shahidul , Ali M. , Al-Majid Abdullah Mohammed , Alshahrani Saeed , Alamary Abdullah Saleh , Yousuf Sammer , Choudhary M. Iqbal
Published: August 2021

A series of new spiro-heterocycles engrafted spirooxindole/pyrrolidine/thiochromene scaffolds was synthesized by the three-component 1,3-dipolar cycloaddition reactions in a fully controlled regio- and stereo-selective fashion. Condensation of several substituted isatin derivatives with L-proline generated the azomethine ylides which subsequently reacted with chalcones based thiochromene scaffold, and finally afforded the target spiro-compounds. This simple protocol furnished a structurally complex, biologically relevant spiro-heterocycles in good yields through a one-pot process. All synthesized chalcone-based thiochromene, along with the spirooxindole/pyrrolidine/thiochromene scaffolds, were tested for their anticancer activity against four cancer cell lines (PC3, HeLa, MCF-7, and MDA-MB231). Toxicity of these compounds was also evaluated against human fibroblast BJ cell line, and they appeared to be not cytotoxic. For the prostate cancer (PC3) cell line, the most active hybrid, among synthesized series, was compound (7f, IC50 = 8.7 ± 0.7 µM). The most potent spirooxindole/pyrrolidine/thiochromene hybrid against cervical (HeLa) cancer cells was compound (7k, IC50 = 8.4 ± 0.5 µM) having chlorine and p-trifluoromethyl substituents attached to phenyl rings. Finally, against the MCF-7 and MDA-MB231 breast cancer cell lines, compound (7d) was the most active member of this series (IC50 = 7.36 ± 0.37, and 9.44 ± 0.32 µM, respectively).
Towards a Soil Remediation Strategy Using Biochar: Effects on Soil Chemical Properties and Bioavailability of Potentially Toxic Elements
Authors: Bilias Fotis , Nikoli Thomai , Kalderis Dimitrios , Gasparatos Dionisios
Published: August 2021

Soil contamination with potentially toxic elements (PTEs) is considered one of the most severe environmental threats, while among remediation strategies, research on the application of soil amendments has received important consideration. This review highlights the effects of biochar application on soil properties and the bioavailability of potentially toxic elements describing research areas of intense current and emerging activity. Using a visual scientometric analysis, our study shows that between 2019 and 2020, research sub-fields like earthworm activities and responses, greenhouse gass emissions, and low molecular weight organic acids have gained most of the attention when biochar was investigated for soil remediation purposes. Moreover, biomasses like rice straw, sewage sludge, and sawdust were found to be the most commonly used feedstocks for biochar production. The effect of biochar on soil chemistry and different mechanisms responsible for PTEs’ immobilization with biochar, are also briefly reported. Special attention is also given to specific PTEs most commonly found at contaminated soils, including Cu, Zn, Ni, Cr, Pb, Cd, and As, and therefore are more extensively revised in this paper. This review also addresses some of the issues in developing innovative methodologies for engineered biochars, introduced alongside some suggestions which intend to form a more focused soil remediation strategy.
Focal Epithelial Hyperplasia
Authors: Bendtsen Simone Kloch , Jakobsen Kathrine Kronberg , Carlander Amanda-Louise Fenger , Grønhøj Christian , von Buchwald Christian
Published: August 2021

Focal epithelial hyperplasia (FEH) or Heck’s disease is a rare, benign, oral condition that is associated with infection by human papillomavirus type 13, 32 or both. The whiteish to mucosal-colored, soft, papular or nodular elevated lesions in the oral cavity are normally asymptomatic but can grow to a size or at a location where treatment is needed. The diagnosis is often based on clinical presentation and histopathology, and the HPV genotype can be determined using PCR utilizing specific primers or DNA sequencing. While FEH was reported to often affect several members of the same family and exist primarily among indigenous populations around the world, the number of reported cases within the European region is increasing. This contemporary review summarizes the main findings in relation to HPV genotypes, impact of superinfection exclusion and vaccination, transmission, diagnosis, geographical and ethnical distribution, comorbidities and treatment of FEH with an emphasis on including the most recent case reports within the field. Furthermore, we describe for the first time a FEH lesion infected with the low-risk HPV90.
Sir Peter Lachmann—Outstanding and Inspirational Immunologist
Authors: McConnell Ian
Published: August 2021

Sir Peter Lachmann was an exceptional and gifted scientist whose intellectual contributions to biomedical science have been immense.[...]
Detection of Human Papillomavirus Integration in Brain Metastases from Oropharyngeal Tumors by Targeted Sequencing
Authors: McEllin Brian , Searle Brian , DePledge Lisa , Sun George , Cobbs Charles , Karimi Mohsen
Published: August 2021

Human papillomavirus (HPV) positive and negative head and neck squamous cell carcinoma (HNSCC) are known to have differential phenotypes, including the incidence and location of metastases. HPV positive (HPV+) HNSCC are more likely to metastasize to distant sites, such as the lung, brain, and skin. Among these locations, metastasis to the brain is a rare event, and little is known about specific risk factors for this phenotype. In this report, we describe two patients who developed brain metastases from HNSCC. Both patient tumors had p16INK4a overexpression, suggesting these tumors were HPV+. This was confirmed after PCR, in situ hybridization, and mass spectrometry detected the presence of HPV type 16 (HPV16) DNA, RNA and protein. To further characterize the presence of HPV16, we used a target enrichment strategy on tumor DNA and RNA to isolate the viral sequences from the brain metastases. Analysis by targeted next generation sequencing revealed that both tumors had the HPV genome integrated into the host genome at known hotspots, 8q24.21 and 14q24.1. Applying a similar target enrichment strategy to a larger cohort of HPV+ HNSCC brain metastases could help to identify biomarkers that can predict metastasis and/or identify novel therapeutic options.
Active Components of Commonly Prescribed Medicines Affect Influenza A Virus–Host Cell Interaction: A Pilot Study
Authors: Ianevski Aleksandr , Yao Rouan , Zusinaite Eva , Lysvand Hilde , Oksenych Valentyn , Tenson Tanel , Bjørås Magnar , Kainov Denis
Published: August 2021

Background: Every year, millions of people are hospitalized and thousands die from influenza A virus (FLUAV) infection. Most cases of hospitalizations and death occur among the elderly. Many of these elderly patients are reliant on medical treatment of underlying chronic diseases, such as arthritis, diabetes, and hypertension. We hypothesized that the commonly prescribed medicines for treatment of underlying chronic diseases can affect host responses to FLUAV infection and thus contribute to the morbidity and mortality associated with influenza. Therefore, the aim of this study was to examine whether commonly prescribed medicines could affect host responses to virus infection in vitro. Methods: We first identified 45 active compounds from a list of commonly prescribed medicines. Then, we constructed a drug–target interaction network and identified the potential implication of these interactions for FLUAV–host cell interplay. Finally, we tested the effect of 45 drugs on the viability, transcription, and metabolism of mock- and FLUAV-infected human retinal pigment epithelial (RPE) cells. Results: In silico drug–target interaction analysis revealed that drugs such as atorvastatin, candesartan, and hydroxocobalamin could target and modulate FLUAV–host cell interaction. In vitro experiments showed that at non-cytotoxic concentrations, these compounds affected the transcription and metabolism of FLUAV- and mock-infected cells. Conclusion: Many commonly prescribed drugs were found to modulate FLUAV–host cell interactions in silico and in vitro and could therefore affect their interplay in vivo, thus contributing to the morbidity and mortality of patients with influenza virus infections.
A Single-Cycle Influenza A Virus-Based SARS-CoV-2 Vaccine Elicits Potent Immune Responses in a Mouse Model
Authors: Koonpaew Surapong , Kaewborisuth Challika , Srisutthisamphan Kanjana , Wanitchang Asawin , Thaweerattanasinp Theeradej , Saenboonrueng Janya , Poonsuk Sukontip , Jengarn Juggragarn , Viriyakitkosol Ratchanont , Kramyu Jarin , Jongkaewwattana Anan
Published: August 2021

The use of virus-vectored platforms has increasingly gained attention in vaccine development as a means for delivering antigenic genes of interest into target hosts. Here, we describe a single-cycle influenza virus-based SARS-CoV-2 vaccine designated as scPR8-RBD-M2. The vaccine utilizes the chimeric gene encoding 2A peptide-based bicistronic protein cassette of the SARS-CoV-2 receptor-binding domain (RBD) and influenza matrix 2 (M2) protein. The C-terminus of the RBD was designed to link with the cytoplasmic domain of the influenza virus hemagglutinin (HA) to anchor the RBD on the surface of producing cells and virus envelope. The chimeric RBD-M2 gene was incorporated in place of the HA open-reading frame (ORF) between the 3′ and 5′ UTR of HA gene for the virus rescue in MDCK cells stably expressing HA. The virus was also constructed with the disrupted M2 ORF in segment seven to ensure that M2 from the RBD-M2 was utilized. The chimeric gene was intact and strongly expressed in infected cells upon several passages, suggesting that the antigen was stably maintained in the vaccine candidate. Mice inoculated with scPR8-RBD-M2 via two alternative prime-boost regimens (intranasal-intranasal or intranasal-intramuscular routes) elicited robust mucosal and systemic humoral immune responses and cell-mediated immunity. Notably, we demonstrated that immunized mouse sera exhibited neutralizing activity against pseudotyped viruses bearing SARS-CoV-2 spikes from various variants, albeit with varying potency. Our study warrants further development of a replication-deficient influenza virus as a promising SARS-CoV-2 vaccine candidate.
COVID-19 Vaccination in Patients with Severe Asthma on Biologic Treatment: Safety, Tolerability, and Impact on Disease Control
Authors: Caminati Marco , Guarnieri Gabriella , Batani Veronica , Scarpieri Elena , Finocchiaro Anita , Chieco-Bianchi Fulvia , Senna Gianenrico , Vianello Andrea
Published: August 2021

Background: COVID-19 vaccination has been recommended for severe asthmatics. We aimed to evaluate the safety, tolerability, and impact on disease control and patient’s quality of life of the mRNA SARS-CoV-2/COVID-19 vaccine in severe asthma patients regarding biologic treatment. Methods: Severe asthmatic patients regularly managed by two big allergy and respiratory referral centers were offered to undergo Pfizer COVID 19 vaccination at the hospital site. Patients filled in an adverse events questionnaire after the first and second dose, as well as the Asthma Control Test (ACT) and Asthma Quality of Life Questionnaire (AQLQ). Results: Overall, 253 patients were vaccinated; only 16 patients refused. No serious events were detected. Less than 20% of patients reported side effects, most of which were classified as very common side effects. No differences were reported according to the ongoing biologic drug. A significant improvement in both ACT and AQLQ was observed between the first and the second dose administration. Conclusions: Our data confirm the optimal safety and tolerability profile of mRNA SARS- CoV-2/COVID-19 in severe asthma patients on biologic treatment, as well as their positive attitude towards COVID-19 vaccination. The negligible proportion of patients reporting side effects and the absence of asthma exacerbations are relevant to support the COVID-19 vaccination campaign in severe asthma patients worldwide.
Signalment and Clinical Data of Cats with Exocrine Pancreatic Insufficiency Diagnosed Using Feline Trypsin-like Immunoreactivity in Routine Diagnostics
Authors: Törner Katrin , Grassinger Julia Maria , Weber Corinna N. , Aupperle-Lellbach Heike , Cerezo-Echevarria Argine , Müller Elisabeth
Published: August 2021

Serum feline trypsin-like immunoreactivity (fTLI) is commonly used to diagnose feline exocrine pancreatic insufficiency (EPI). This study aimed to describe signalment and clinical data of cats with EPI. Determination of TLI was performed using an in-house ELISA; the reference interval was defined using a Reference Limit Estimator. Groups were formed from 4813 cats (2019–2020), based on their fTLI concentration: 1 (<8 µg/L; decreased; n = 275), 2 (8–88 µg/L; reference interval; n = 4256), and 3 (>88 µg/L; increased; n = 282). Males and Domestic Shorthairs were most common in all groups. Group 3 had the highest (13 years), and group 1 had the lowest (9 years), median age. Clinical information was available for 200 cats (decreased fTLI: n = 87, lower reference interval (8–12 µg/L): n = 113). Treatment response was observed in 83% (decreased fTLI) and 66% (lower reference interval). EPI cats displayed weight loss (69%), diarrhoea (68%), vomiting (41%), anorexia (39%), poor hair coat (35%), lethargy (33%), and/or polyphagia (21%). The lower the serum fTLI concentration, the more often good treatment response was reported (p = 0.022) but there were no statistically significant clinical signs. In conclusion, fTLI is a helpful parameter to diagnose EPI but predicting treatment response based on signalment or clinical signs is not possible.